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<article xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink" article-type="research-article" dtd-version="1.1" specific-use="sps-1.7" xml:lang="en">
  <front>
    <journal-meta>
      <journal-id journal-id-type="publisher-id">ijcs</journal-id>
      <journal-title-group>
        <journal-title>International Journal of Cardiovascular Sciences</journal-title>
        <abbrev-journal-title abbrev-type="publisher">Int. J. Cardiovasc. Sci.</abbrev-journal-title>
      </journal-title-group>
      <issn pub-type="ppub">2359-4802</issn>
      <issn pub-type="epub">2359-5647</issn>
      <publisher>
        <publisher-name>Sociedade Brasileira de Cardiologia</publisher-name>
      </publisher>
    </journal-meta>
    <article-meta>
      <article-id pub-id-type="publisher-id" specific-use="scielo-v3">PXRRHfzWXDSmr5WHbyfzHWS</article-id>
      <article-id pub-id-type="publisher-id" specific-use="scielo-v2">S2359-56472018000100063</article-id>
      <article-id pub-id-type="doi">10.5935/2359-4802.20170092</article-id>
      <article-categories>
        <subj-group subj-group-type="heading">
          <subject>Original Articles</subject>
        </subj-group>
      </article-categories>
      <title-group>
        <article-title>Expansion Pulmonary Therapy in Blood Oxygenation and Lactate Serum Level in Postoperative Cardiac Surgery</article-title>
      </title-group>
      <contrib-group>
        <contrib contrib-type="author">
          <name>
            <surname>Oliveira</surname>
            <given-names>Silvana Souza</given-names>
          </name>
          <xref ref-type="aff" rid="aff1"/>
          <xref ref-type="corresp" rid="c1"/>
        </contrib>
        <contrib contrib-type="author">
          <name>
            <surname>Neto</surname>
            <given-names>Mansueto</given-names>
          </name>
          <xref ref-type="aff" rid="aff1"/>
        </contrib>
        <contrib contrib-type="author">
          <name>
            <surname>Aras</surname>
            <given-names>Roque</given-names>
            <suffix>Junior</suffix>
          </name>
          <xref ref-type="aff" rid="aff1"/>
        </contrib>
        <aff id="aff1">
          <institution content-type="orgname">Universidade Federal da Bahia</institution>
          <institution content-type="orgdiv1">Programa de P&#243;s-gradua&#231;&#227;o em Medicina e Sa&#250;de</institution>
          <addr-line>
            <city>Salvador</city>
            <state>BA</state>
          </addr-line>
          <country country="BR">Brazil</country>
          <institution content-type="original">Programa de P&#243;s-gradua&#231;&#227;o em Medicina e Sa&#250;de da Universidade Federal da Bahia, Salvador, BA - Brazil</institution>
          <institution content-type="normalized">Universidade Federal da Bahia</institution>
        </aff>
      </contrib-group>
      <author-notes>
        <corresp id="c1"><bold>Mailing Address: Silvana Souza Oliveira,</bold> Rua Desembargador Gilberto Andrade, 256, Edf. Santo In&#225;cio, apt. 201. Code Postal: 40155200, Chame Chame, Salvador, BA - Brazil. E-mail: <email>silvanaso@oi.com.br</email>
				</corresp>
        <fn fn-type="con">
          <p>
            <bold>Author contributions</bold>
          </p>
          <p>Conception and design of the research: Oliveira SS, Neto M, Aras Junior R. Acquisition of data: Oliveira SS. Analysis and interpretation of the data: Oliveira SS, Neto M. Statistical analysis: Oliveira SS, Neto M. Writing of the manuscript: Oliveira SS, Neto M, Aras Junior R. Critical revision of the manuscript for intellectual content: Oliveira SS, Neto M, Aras Junior R.</p>
        </fn>
        <fn fn-type="conflict">
          <p>
            <bold>Potential Conflict of Interest</bold>
          </p>
          <p>No potential conflict of interest relevant to this article was reported.</p>
        </fn>
      </author-notes>
      <pub-date pub-type="epub-ppub">
        <season>Jan-Feb</season>
        <year>2018</year>
      </pub-date>
      <volume>31</volume>
      <issue>1</issue>
      <fpage>63</fpage>
      <lpage>70</lpage>
      <history>
        <date date-type="received">
          <day>10</day>
          <month>11</month>
          <year>2016</year>
        </date>
        <date date-type="rev-recd">
          <day>15</day>
          <month>02</month>
          <year>2017</year>
        </date>
        <date date-type="accepted">
          <day>17</day>
          <month>07</month>
          <year>2017</year>
        </date>
      </history>
      <permissions>
        <license license-type="open-access" xlink:href="https://creativecommons.org/licenses/by/4.0/" xml:lang="en">
          <license-p>This is an Open Access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited</license-p>
        </license>
      </permissions>
      <abstract>
        <title>Abstract</title>
        <sec>
          <title>Background:</title>
          <p>Cardiovascular and pulmonary complications often occur in the immediate post- surgery period and may be prevented and/or treated with lung expansion techniques.</p>
        </sec>
        <sec>
          <title>Objective:</title>
          <p>To evaluate the efficacy of lung expansion techniques in serum arterial lactate levels and oxygenation in patients in this surgical recovery phase.</p>
        </sec>
        <sec>
          <title>Method:</title>
          <p>A prospective and analytical study was carried out in postoperative cardiac surgery patients, hemodynamically stable. Measurements of artery lactate levels and partial pressure of oxygen were obtained from arterial blood samples drawn before and after lung expansion techniques, including alveolar recruiting maneuver and intermittent positive pressure breathing.</p>
        </sec>
        <sec>
          <title>Results:</title>
          <p>40 patients with average age of 51.1 &#177; 14.9 years, 55% female, were included. It is possible to observe the statistically significant difference (p &lt; 0.05) in the comparison between values of baseline and post-operative arterial lactate, oxygen level, oxygen saturation/fraction of inspired oxygen in both procedures. In relation to the outcome of oxygen blood pressure, only the group on intermittent positive pressure breathing achieved significant improvement.</p>
        </sec>
        <sec>
          <title>Conclusion:</title>
          <p>The lung expansion techniques used have contributed with the reduction of lactate level, improvement in oxygenation and oxygen saturation in this population, but did not alter intensive care unit length of stay.</p>
        </sec>
      </abstract>
      <kwd-group xml:lang="en">
        <title>Keywords:</title>
        <kwd>Thoracic Surgery</kwd>
        <kwd>Physical Therapy Modalities</kwd>
        <kwd>Postoperative Care</kwd>
        <kwd>Oxygenation</kwd>
        <kwd>Oxygen Level</kwd>
        <kwd>L-Lactate Dehydrogenase</kwd>
      </kwd-group>
    </article-meta>
  </front>
  <body>
    <sec sec-type="intro">
      <title>Introduction</title>
      <p>Cardiovascular diseases are among the main causes of morbidity and mortality around the world, involving great financial investment and affecting the population&#8217;s health. Therapeutic strategies include prevention, medication, <italic>endocardiovascular intervention</italic> and cardiac surgery.<xref ref-type="bibr" rid="B1">1</xref> Cardiac surgery, notably revascularization and valve replacement, have changed patient&#8217;s life expectancy and improved their survival and quality of life.<xref ref-type="bibr" rid="B2">2</xref>
			</p>
      <p>In spite of the evident benefits of cardiac surgery, cardiovascular and pulmonary complications frequently occur in the <italic>immediate postoperative period</italic>, compromising the evolution of patients with reduced oxygenation and elevated arterial lactate levels attributed to tissue hypotension, hypoxemia and <italic>intrapulmonary shunt</italic>, increasing hospital stay, <italic>with a potential to cause death.</italic><xref ref-type="bibr" rid="B3">3</xref><sup>-</sup><xref ref-type="bibr" rid="B6">6</xref>
			</p>
      <p>Pulmonary complications may cause <italic>deviation</italic> to <italic>anaerobic metabolism</italic> with <italic>metabolic acidosis</italic>, elevated lactate levels and <italic>microvascular circulation damage,</italic><xref ref-type="bibr" rid="B7">7</xref><sup>-</sup><xref ref-type="bibr" rid="B10">10</xref> which may be prevented or resolved by l<italic>ung expansion techniques, inducing an</italic>
				<italic>increase in lung volumes and capacities,</italic> through increased <italic>transpulmonary pressure gradient</italic> and thus improve them, whether the patient is <italic>receiving mechanical ventilation</italic> or <italic>breathing ambient air</italic>.<xref ref-type="bibr" rid="B11">11</xref>
			</p>
      <p>Among the lung expansion techniques, we can cite <italic>alveolar recruitment maneuver in patients attached to a mechanical ventilator</italic> to improve oxygenation, reduce <italic>ventilator-associated lung injury</italic> and facilitate weaning and extubation,<xref ref-type="bibr" rid="B12">12</xref> and intermittent positive pressure in patients breathing spontaneously, aiming to increase <italic>tidal volume</italic>, improve gas exchange and direct air into <italic>hypoventilation zones.</italic><xref ref-type="bibr" rid="B13">13</xref><sup>,</sup><xref ref-type="bibr" rid="B14">14</xref>
			</p>
      <p><italic>Studies have shown</italic> the significant effects of lung expansion techniques in patients with lung disease, however there are few studies that have tested the use of the techniques in patients with cardiac disease, especially in the postoperative of cardiac surgery. As a result, the purpose of this study was to evaluate the effects of lung expansion techniques in arterial lactate levels and oxygenation in patients in the <italic>immediate cardiac surgery postoperative</italic> phase.</p>
    </sec>
    <sec sec-type="methods">
      <title>Methods</title>
      <p>A prospective and analytical study was carried out at the postoperative cardiac surgery unit of H<italic>ospital</italic> Ana Nery - UFBA/SESAB, a <italic>reference center in the treatment of cardiovascular diseases in</italic> the State of Bahia, Brazil.</p>
      <p>It included patients over 18 years of age, <italic>hemodynamically stable, with an average blood pressure</italic> of 60 mmHg or higher, and who needed to be treated with lung expansion techniques due to their clinical evolution. <italic>Patients who presented the following were excluded</italic>: <italic>psychomotor agitation</italic>, intracranial hypertension, p<italic>ulmonary hypertension, pneumopathy</italic> and/or <italic>previous pneumonectomy, chronic obstructive pulmonary disease, non-drained pneumothorax, pneumomediastinum, hemoptysis, reduction in cardiac output and</italic> on <italic>intra-aortic balloon, body mass index greater than 30 kg/m(<sup>2</sup>. The project was approved by the Ethics Committee of Hospital Ana Nery</italic> - UFBA/SESAB, under protocol 861.257.</p>
      <p><italic>Measurements of lactate level</italic> and <italic>partial pressure of oxygen in arterial blood</italic>, inspiratory fraction <italic>and oxygen saturation</italic>, were drawn before and after intervention of lung expansion techniques, in order to determine variations of arterial lactate levels and <italic>oxygenation index resulting from</italic> the use of these techniques <italic>in the recovery phase</italic>.</p>
      <p>Clinical, surgical, laboratory and hemodynamic parameters, such as heart rate and mean arterial pressure were <italic>monitored using a multi-parameter monitor</italic> (Portal DX2020 DIXTAL&#174;). <italic>Partial pressure of oxygen in arterial blood</italic>, lactate, fraction of inspired oxygen and oxygen saturation were analyzed through a hemogasometer (Roche COBAS b20&#174;), every six hours, <italic>after patients arrived in the postoperative care unit</italic>, or while on invasive mechanical ventilation, in conformity with the standards of that intensive therapy unit. <italic>Oxygen relation</italic> was <italic>calculated</italic> as the <italic>arterial blood oxygen partial pressure divided</italic> by the <italic>fraction of inspired oxygen</italic>, according to the 3rd <italic>Brazilian</italic> Consensus on <italic>Mechanical Ventilation</italic>.<xref ref-type="bibr" rid="B15">15</xref> In the <italic>anesthesia sheet</italic>, it was recorded the <italic>aortic clamping time</italic> or period of anoxia, time of <italic>extracorporeal circulation and the total anesthesia time</italic>, the surgery performed and if the patient <italic>had undergone volume expansion</italic> after admission to the postoperative unit.</p>
      <p><italic>The mechanical ventilation protocol used included</italic> admission of all patients to a<italic>volume-controlled ventilation mode</italic> (VCV), <italic>with inspired oxygen fraction of</italic> 0.6 (60%), <italic>positive end-expiratory pressure</italic> of 5 cmH<sub>2</sub>O, respiratory frequency from 12 to 20 rpm and tidal volume ranging from 6 to 8 ml/Kg. After the result of the first hemogasometry, the ventilation mode <italic>was replaced by pressure-controlled ventilation</italic> (PCV), with decreasing inspiratory flow rate from 40 to 50 l/min, inspiratory pause of 0.2 seconds, respiratory frequency from 12 to 15 rpm, <italic>positive end-expiratory pressure</italic> of 5 cmH<sub>2</sub>O. If the <italic>ratio of partial pressure arterial oxygen and fraction of inspired oxygen</italic> were less than 200, <italic>positive end-expiratory pressure</italic> should be increased to 8 cmH<sub>2</sub>O with a <italic>fraction of inspired oxygen</italic> of 0.6 (60%). To proceed to extubation, pressure support ventilation (PSV) was used, and afterwards all patients received oxygen supplementation via a nasal catheter, respiratory and motor physiotherapy, including coughing exercises.</p>
      <p>The lung expansion techniques used were: alveolar recruitment maneuver or intermittent positive pressure breathing using the Maquet Servo ventilator or the VELA <italic>TBird Series</italic>&#174;. They were chosen to follow the hospital's operating procedures, and the way they are performed in the postoperative unit. The blood for hemogasometric evaluation was collected of the artery fifteen minutes before and after any procedure of lung expansion techniques was made, in order to assess lactate level dosage and oxygenation. Each individual was compared with himself, before and after hemogasometric evaluation.</p>
      <p>The choice of the procedure of the lung expansion technique to be performed and the physiotherapist's conduct depended on the evolution and respiratory condition of the patient, verified using the hemogasometry analysis and the result of a chest radiograph. If the patient were attached to mechanical ventilation, the technique applied was alveolar recruitment maneuver; when he was breathing to the ambient air, intermittent positive pressure breathing was applied.</p>
      <p>Alveolar recruitment maneuver was applied when the patient presented a <italic>ratio of partial pressure arterial oxygen and fraction of inspired oxygen</italic> less than or equal to 201 or less than 250 before extubation. Pressure-controlled ventilation, PCV,<xref ref-type="bibr" rid="B16">16</xref><sup>,</sup><xref ref-type="bibr" rid="B17">17</xref> was used with a positive-end expiratory pressure of 25 cmH<sub>2</sub>O<xref ref-type="bibr" rid="B18">18</xref><sup>,</sup><xref ref-type="bibr" rid="B19">19</xref>, below what is recommended by the 3rd <italic>Brazilian</italic> Consensus on <italic>Mechanical Ventilation</italic><xref ref-type="bibr" rid="B15">15</xref> to ensure security and avoid alveolar collapse during the expiratory phase<xref ref-type="bibr" rid="B18">18</xref> . It was performed progressively from baseline positive-end expiratory pressure, raised at 20 seconds intervals in increments of 5 cmH2O, until the determined value of positive-end expiratory pressure was reached<xref ref-type="bibr" rid="B18">18</xref>, with an inspiratory pressure of 15 cmH<sub>2</sub>O, performed using three cycles for 40 seconds.<xref ref-type="bibr" rid="B6">6</xref><sup>,</sup><xref ref-type="bibr" rid="B20">20</xref><sup>,</sup><xref ref-type="bibr" rid="B21">21</xref> At one-minute intervals between each cycle, positive-end expiratory pressure decreased back to 15 cmH<sub>2</sub>O.<xref ref-type="bibr" rid="B21">21</xref> At the end of the procedure, a new complete evaluation was performed. The results obtained were observed and registered. In addition, in all patients the positive-end expiratory pressure was 2 cmH<sub>2</sub>O above the positive end-expiratory pressure before initial recruitment.</p>
      <p>Intermittent positive pressure breathing was performed in patients with spontaneous breathing and if they needed pulmonary reexpansion according to the physical exam and the result of chest radiograph. The patient was placed in a 90-degree sitting position, evaluated and oriented about the procedure. Inspiratory pressure was set at 10 cmH<sub>2</sub>O and positive end-expiratory pressure at 15 cmH<sub>2</sub>O, with facemask use. Three two-minute cycles were performed with a one-minute interval between the cycles, once each turn. Afterwards, a new complete evaluation was performed and the results obtained were observed and registered.</p>
      <p>All the patients were evaluated before, during and after any intervention of lung expansion techniques. As a result, data collection was interrupted in case the patient, monitored using a multi-parameter monitor, presented hemodynamic instability. During any procedure of lung expansion techniques, the hemodynamic instabilities considered were: mean blood pressure less than 60 mmHg or peripheral oxygen saturation less than 90% and heart rate greater or less than 30% of the value obtained in the evaluation performed prior to the execution of the techniques.</p>
      <sec>
        <title>Statistical analysis</title>
        <p>Data collected were stored using tables in the <italic>software Microsoft Exc</italic>el&#174; (<italic>Microsoft Corporation, Mountain View, CA, EUA</italic>, version 2003). Demographic and clinical data were analyzed using descriptive statistics. Continuous variables data were analyzed using measures of central tendency and dispersion, expressed as mean and standard deviation, using parametric statistical tests. Dichotomous or Categorical Variables were analyzed using frequency measures and expressed as percentage. To compare before and after periods, data normality was calculated using the normality test. Afterwards, a paired T-test was used, considering the significance level of 5%. The <italic>Statistical Package for Social Science</italic> (SPSS) <italic>for Windows</italic> (<italic>SPSS Inc., Chicago, IL, EUA</italic>, version 20 or superior) was used to analyze the data.</p>
      </sec>
    </sec>
    <sec sec-type="results">
      <title>Results</title>
      <p>Forty patients of convenience were admitted to the post-surgical unit, who required the following, according to their clinical evolution and respiratory condition: alveolar recruitment maneuver, used in 18 patients, intermittent positive pressure breathing, applied in 22 individuals. No patient required both techniques, ven in different moment of their recovery period. The description of the demographic and clinical characteristics are shown in <xref ref-type="table" rid="t1">Table 1</xref>.</p>
      <table-wrap id="t1">
        <label>Table 1</label>
        <caption>
          <title>Total Sample Characterization. n = 40 patients</title>
        </caption>
        <table frame="hsides" rules="groups">
          <colgroup>
            <col width="33%"/>
            <col width="33%"/>
            <col width="33%"/>
          </colgroup>
          <thead>
            <tr>
              <th align="left" style="background-color:#C5C6C8">
							</th>
              <th align="center" style="background-color:#C5C6C8">Mean &#177; Standard Deviation</th>
              <th align="center" style="background-color:#C5C6C8">Frequency (%)</th>
            </tr>
          </thead>
          <tbody>
            <tr>
              <td align="left">Age (years)</td>
              <td align="center">51.1&#177;14.9</td>
              <td align="center">--</td>
            </tr>
            <tr>
              <td align="left">Gender (female)</td>
              <td align="center">--</td>
              <td align="center">22 (55%)</td>
            </tr>
            <tr>
              <td align="left">MBI (Kg/m<sup>2</sup>)<xref ref-type="table-fn" rid="TFN1">*</xref>
							</td>
              <td align="center">24.4&#177;4.3</td>
              <td align="center">--</td>
            </tr>
            <tr>
              <td align="left">Civil Status</td>
              <td align="center">
							</td>
              <td align="center">
							</td>
            </tr>
            <tr>
              <td align="left">Single</td>
              <td align="center">--</td>
              <td align="center">13 (32.5%)</td>
            </tr>
            <tr>
              <td align="left">Married</td>
              <td align="center">--</td>
              <td align="center">23 (57.5%)</td>
            </tr>
            <tr>
              <td align="left">Divorced</td>
              <td align="center">--</td>
              <td align="center">3 (7.5%)</td>
            </tr>
            <tr>
              <td align="left">Widow</td>
              <td align="center">--</td>
              <td align="center">1 (2.5%)</td>
            </tr>
            <tr>
              <td align="left">Non-diabetic</td>
              <td align="center">--</td>
              <td align="center">32 (80%)</td>
            </tr>
            <tr>
              <td align="left">Non-smoker</td>
              <td align="center">--</td>
              <td align="center">24 (60%)</td>
            </tr>
            <tr>
              <td align="left">LV Ejection Fraction (%)<xref ref-type="table-fn" rid="TFN2">&#8224;</xref>
							</td>
              <td align="center">59.6&#177;9.7</td>
              <td align="center">--</td>
            </tr>
          </tbody>
        </table>
        <table-wrap-foot>
          <fn id="TFN1">
            <label>*</label>
            <p>BMI: Body Mass Index;</p>
          </fn>
          <fn id="TFN2">
            <label>&#8224;</label>
            <p>LV:Left Ventricular</p>
          </fn>
        </table-wrap-foot>
      </table-wrap>
      <p>Alveolar recruitment maneuver was performed in 18 patients and intermittent positive pressure breathing was applied to 22 patients. The demographic and clinical characteristics are described in <xref ref-type="table" rid="t2">tables 2</xref> and <xref ref-type="table" rid="t3">3</xref>, respectively.</p>
      <table-wrap id="t2">
        <label>Table 2</label>
        <caption>
          <title>Characteristics of the 18 patients who underwent Alveolar Recruitment Maneuver (ARM)</title>
        </caption>
        <table frame="hsides" rules="groups">
          <colgroup>
            <col width="33%"/>
            <col width="33%"/>
            <col width="33%"/>
          </colgroup>
          <thead>
            <tr>
              <th align="left" style="background-color:#C5C6C8">
							</th>
              <th align="center" style="background-color:#C5C6C8">Mean &#177; Standard Deviation</th>
              <th align="center" style="background-color:#C5C6C8">Frequency (%)</th>
            </tr>
          </thead>
          <tbody>
            <tr>
              <td align="left">Age (years)</td>
              <td align="center">49.6 &#177; 16.8</td>
              <td align="center">--</td>
            </tr>
            <tr>
              <td align="left">Gender (female)</td>
              <td align="center">--</td>
              <td align="center">8 (42.1%)</td>
            </tr>
            <tr>
              <td align="left">MBI (Kg/m<sup>2</sup>)<xref ref-type="table-fn" rid="TFN3">*</xref>
							</td>
              <td align="center">23,2 &#177; 4,1</td>
              <td align="center">--</td>
            </tr>
            <tr>
              <td align="left">Civil Status</td>
              <td align="center">
							</td>
              <td align="center">
							</td>
            </tr>
            <tr>
              <td align="left">Single</td>
              <td align="center">--</td>
              <td align="center">4 (21.1%)</td>
            </tr>
            <tr>
              <td align="left">Married</td>
              <td align="center">--</td>
              <td align="center">10 (52.6%)</td>
            </tr>
            <tr>
              <td align="left">Divorced</td>
              <td align="center">--</td>
              <td align="center">3 (15.8%)</td>
            </tr>
            <tr>
              <td align="left">Widow</td>
              <td align="center">--</td>
              <td align="center">1 (5.3%)</td>
            </tr>
            <tr>
              <td align="left">Non-diabetic</td>
              <td align="center">--</td>
              <td align="center">17 (89.5%)</td>
            </tr>
            <tr>
              <td align="left">Non-smoker</td>
              <td align="center">--</td>
              <td align="center">10 (52.6%)</td>
            </tr>
            <tr>
              <td align="left">LV Ejection Fraction (%)<xref ref-type="table-fn" rid="TFN4">&#8224;</xref>
							</td>
              <td align="center">61.1 &#177; 7.7</td>
              <td align="center">--</td>
            </tr>
            <tr>
              <td align="left">Surgery Performed</td>
              <td align="center">
							</td>
              <td align="center">
							</td>
            </tr>
            <tr>
              <td align="left">Mitral Valve Replacement</td>
              <td align="center">--</td>
              <td align="center">3 (15.8%)</td>
            </tr>
            <tr>
              <td align="left">Aortic Valve Replacement</td>
              <td align="center">--</td>
              <td align="center">1 (5.3%)</td>
            </tr>
            <tr>
              <td align="left">Double Valve Replacement</td>
              <td align="center">--</td>
              <td align="center">5 (26.3%)</td>
            </tr>
            <tr>
              <td align="left">Miocardial Revascularization</td>
              <td align="center">--</td>
              <td align="center">5 (26.3%)</td>
            </tr>
            <tr>
              <td align="left">Aortic Valve Replacement + Myocardial Revascularization</td>
              <td align="center">--</td>
              <td align="center">2 (10.5%)</td>
            </tr>
            <tr>
              <td align="left">Mitral Valve Replacement + Myocardial Revascularization</td>
              <td align="center">--</td>
              <td align="center">1 (5.3%)</td>
            </tr>
            <tr>
              <td align="left">Tetralogy of Fallot</td>
              <td align="center">--</td>
              <td align="center">1 (5.3%)</td>
            </tr>
            <tr>
              <td align="left">Time of Surgery (Hours)</td>
              <td align="center">5.9 &#177; 1.1</td>
              <td align="center">
							</td>
            </tr>
            <tr>
              <td align="left">Anoxia (minutes)</td>
              <td align="center">87.3 &#177; 42.4</td>
              <td align="center">--</td>
            </tr>
            <tr>
              <td align="left">CEC (minutos)<xref ref-type="table-fn" rid="TFN4">&#8224;</xref>
							</td>
              <td align="center">118.3 &#177; 54.8</td>
              <td align="center">--</td>
            </tr>
            <tr>
              <td align="left">POU length of stay (days)<xref ref-type="table-fn" rid="TFN5">&#8225;</xref>
							</td>
              <td align="center">5.2 &#177; 6.9</td>
              <td align="center">--</td>
            </tr>
          </tbody>
        </table>
        <table-wrap-foot>
          <fn id="TFN3">
            <label>*</label>
            <p>BMI: Body Mass Index;</p>
          </fn>
          <fn id="TFN4">
            <label>&#8224;</label>
            <p>EC: Extraxcorporeal Circulation;</p>
          </fn>
          <fn id="TFN5">
            <label>&#8225;</label>
            <p>POU: Postoperative Unit</p>
          </fn>
        </table-wrap-foot>
      </table-wrap>
      <table-wrap id="t3">
        <label>Table 3</label>
        <caption>
          <title>Characteristics of the 22 patients who underwent Intermittent Positive Pressure Breathing (IPPB)</title>
        </caption>
        <table frame="hsides" rules="groups">
          <colgroup>
            <col width="33%"/>
            <col width="33%"/>
            <col width="33%"/>
          </colgroup>
          <thead>
            <tr>
              <th align="left" style="background-color:#C5C6C8">
							</th>
              <th align="center" style="background-color:#C5C6C8">Mean &#177; Standard Deviation</th>
              <th align="center" style="background-color:#C5C6C8">Frequency (%)</th>
            </tr>
          </thead>
          <tbody>
            <tr>
              <td align="left">Age (years)</td>
              <td align="center">52.3 &#177; 13.6</td>
              <td align="center">--</td>
            </tr>
            <tr>
              <td align="left">Gender (female)</td>
              <td align="center">--</td>
              <td align="center">14 (46.7%)</td>
            </tr>
            <tr>
              <td align="left">MBI (Kg/m<sup>2</sup>)<xref ref-type="table-fn" rid="TFN6">*</xref>
							</td>
              <td align="center">25.4 &#177; 4.4</td>
              <td align="center">--</td>
            </tr>
            <tr>
              <td align="left">
                <bold>Civil Status</bold>
              </td>
              <td align="center">
							</td>
              <td align="center">
							</td>
            </tr>
            <tr>
              <td align="left">Single</td>
              <td align="center">--</td>
              <td align="center">9 (30%)</td>
            </tr>
            <tr>
              <td align="left">Married</td>
              <td align="center">--</td>
              <td align="center">13 (43.3%)</td>
            </tr>
            <tr>
              <td align="left">Divorced</td>
              <td align="center">--</td>
              <td align="center">15 (50%)</td>
            </tr>
            <tr>
              <td align="left">Widow</td>
              <td align="center">--</td>
              <td align="center">19 (63.3%)</td>
            </tr>
            <tr>
              <td align="left">Non-diabetic</td>
              <td align="center">58.5 &#177; 11.2</td>
              <td align="center">--</td>
            </tr>
            <tr>
              <td align="left">
                <bold>Non-smoker</bold>
              </td>
              <td align="center">
							</td>
              <td align="center">
							</td>
            </tr>
            <tr>
              <td align="left">LV Ejection Fraction (%)<xref ref-type="table-fn" rid="TFN7">&#8224;</xref>
							</td>
              <td align="center">--</td>
              <td align="center">5 (16.7%)</td>
            </tr>
            <tr>
              <td align="left">Surgery Performed</td>
              <td align="center">--</td>
              <td align="center">2 (6.7%)</td>
            </tr>
            <tr>
              <td align="left">Mitral Valve Replacement</td>
              <td align="center">--</td>
              <td align="center">4 (13.3%)</td>
            </tr>
            <tr>
              <td align="left">Aortic Valve Replacement</td>
              <td align="center">--</td>
              <td align="center">9 (30%)</td>
            </tr>
            <tr>
              <td align="left">Double Valve Replacement</td>
              <td align="center">--</td>
              <td align="center">1 (3.3%)</td>
            </tr>
            <tr>
              <td align="left">Miocardial Revascularization</td>
              <td align="center">--</td>
              <td align="center">1 (3.3%)</td>
            </tr>
            <tr>
              <td align="left">Aortic Valve Replacement + Myocardial Revascularization</td>
              <td align="center">
							</td>
              <td align="center">
							</td>
            </tr>
            <tr>
              <td align="left">Mitral Valve Replacement + Myocardial Revascularization</td>
              <td align="center">5.6 &#177; 0.8</td>
              <td align="center">--</td>
            </tr>
            <tr>
              <td align="left">Tetralogy of Fallot</td>
              <td align="center">76.1 &#177; 31.2</td>
              <td align="center">--</td>
            </tr>
            <tr>
              <td align="left">Time of Surgery (Hours)</td>
              <td align="center">90.3 &#177; 33.3</td>
              <td align="center">--</td>
            </tr>
            <tr>
              <td align="left">Anoxia (minutes)</td>
              <td align="center">3.3 &#177; 1.8</td>
              <td align="center">--</td>
            </tr>
          </tbody>
        </table>
        <table-wrap-foot>
          <fn id="TFN6">
            <label>*</label>
            <p>BMI: Body Mass Index;</p>
          </fn>
          <fn id="TFN7">
            <label>&#8224;</label>
            <p>EC: Extraxcorporeal Circulation;</p>
          </fn>
          <fn id="TFN8">
            <p>&#8225; POU: Postoperative Unit.</p>
          </fn>
        </table-wrap-foot>
      </table-wrap>
      <p>Values of baseline and post-intervention of the alveolar recruitment maneuver and intermittent positive pressure breathing groups are described in <xref ref-type="table" rid="t4">Table 4</xref>, for the following variables: arterial lactate, oxygenation rate, partial pressure of oxygen in arterial blood, inspired fraction and in oxygen saturation. It is possible to observe the significant statistically difference in the comparison of baseline values and post-intervention in both procedures in all variables, with the exception of the Partial Pressure of Oxygen in the arterial blood variable in the alveolar recruitment maneuver group.</p>
      <table-wrap id="t4">
        <label>Table 4</label>
        <caption>
          <title>Mean, standard deviation and p value before and after the following techniques: alveolar recruitment maneuver (ARM) of n = 18 and intermittent positive pressure breathing (IPPB) of n = 22</title>
        </caption>
        <table frame="hsides" rules="groups">
          <colgroup>
            <col width="20%"/>
            <col width="20%"/>
            <col width="20%"/>
            <col width="20%"/>
            <col width="20%"/>
          </colgroup>
          <thead>
            <tr>
              <th align="left" rowspan="2" style="background-color:#C5C6C8">
							</th>
              <th align="center" rowspan="2" style="background-color:#C5C6C8">
							</th>
              <th align="center" style="border-bottom-width:thin;border-bottom-style:solid;background-color:#C5C6C8">Pre-evalution</th>
              <th align="center" style="border-bottom-width:thin;border-bottom-style:solid;background-color:#C5C6C8">Post-evaluation</th>
              <th align="center" style="border-bottom-width:thin;border-bottom-style:solid;background-color:#C5C6C8">p value</th>
            </tr>
            <tr>
              <th align="center" style="background-color:#C5C6C8">Mean &#177; Standard Deviation</th>
              <th align="center" style="background-color:#C5C6C8">Mean &#177; Standard Deviation</th>
              <th align="center" style="background-color:#C5C6C8">
							</th>
            </tr>
          </thead>
          <tbody>
            <tr>
              <td align="left" rowspan="2">Aterial Lactate (mmol/L)</td>
              <td align="center">ARM</td>
              <td align="center">5.7 &#177; 2.4</td>
              <td align="center">3.8 &#177; 1.6</td>
              <td align="center">0.002</td>
            </tr>
            <tr>
              <td align="center">IPPB</td>
              <td align="center">3.4 &#177; 0.9</td>
              <td align="center">2.0 &#177; 0.7</td>
              <td align="center">&#8804; 0</td>
            </tr>
            <tr>
              <td align="left" rowspan="2">Oxygenation Rate (mmHg)</td>
              <td align="center">ARM</td>
              <td align="center">287.4 &#177; 121.3</td>
              <td align="center">432.0 &#177; 186.3</td>
              <td align="center">0.005</td>
            </tr>
            <tr>
              <td align="center">IPPB</td>
              <td align="center">337.4 &#177; 133.9</td>
              <td align="center">513.6 &#177; 198.8</td>
              <td align="center">&#8804; 0</td>
            </tr>
            <tr>
              <td align="left" rowspan="2">Pressure of Oxygen (mmHg)</td>
              <td align="center">ARM</td>
              <td align="center">123.6 &#177; 34.4</td>
              <td align="center">132.1 &#177; 54.1</td>
              <td align="center">0,579</td>
            </tr>
            <tr>
              <td align="center">IPPB</td>
              <td align="center">94.2 &#177; 31.6</td>
              <td align="center">108.8 &#177; 41.0</td>
              <td align="center">= 0.016</td>
            </tr>
            <tr>
              <td align="left" rowspan="2">Inspired Fraction (%)</td>
              <td align="center">ARM</td>
              <td align="center">46.1 &#177; 10.9</td>
              <td align="center">31.5 &#177; 6.7</td>
              <td align="center">&#8804; 0</td>
            </tr>
            <tr>
              <td align="center">IPPB</td>
              <td align="center">31.7 &#177; 16.9</td>
              <td align="center">21.3 &#177; 0.9</td>
              <td align="center">= 0.008</td>
            </tr>
            <tr>
              <td align="left" rowspan="2">Oxygen Saturation (%)</td>
              <td align="center">ARM</td>
              <td align="center">96.4 &#177; 2.1</td>
              <td align="center">98.5 &#177; 1.1</td>
              <td align="center">&#8804; 0</td>
            </tr>
            <tr>
              <td align="center">IPPB</td>
              <td align="center">95.6 &#177; 1.5</td>
              <td align="center">98.0 &#177; 0.8</td>
              <td align="center">&#8804; 0</td>
            </tr>
          </tbody>
        </table>
      </table-wrap>
    </sec>
    <sec sec-type="discussion">
      <title>Discussion</title>
      <p>The results found in this study leads to the conclusion that the procedures of lung expansion techniques contribute reduce arterial lactate levels and improve oxygenation in patients in the postoperative of cardiac surgery. Our results are attributed to airway and alveolar expansion as a result of the use of positive pressure, which promoted better ventilation in areas previously collapsed.</p>
      <p>Alveolar recruitment maneuver provides better distribution of alveolar gas, maximizing gas exchange and improving arterial oxygenation.<xref ref-type="bibr" rid="B22">22</xref> It was observed that this technique contributed to the reduction of arterial blood lactate level. Auler Jr et al.<xref ref-type="bibr" rid="B23">23</xref> carried out a prospective study with 40 patients, in which they evaluated the effects of alveolar recruitment maneuver on oxygenation and exhaled tidal volume,in patients with hypoxemia in the immediate postoperative period of cardiac surgery, and concluded that, after this technique was performed, there was an increase in the oxygenation rate and peripheral oxygen saturation, which corroborates the results of this study.</p>
      <p>Celebri et al.<xref ref-type="bibr" rid="B11">11</xref> randomized 60 patients in the postoperative of myocardial revascularization in three groups of 20 patients, G1 (CPAP + alveolar recruitment maneuver), G2 (PEEP-20 + alveolar recruitment maneuver) e G3 (PEEP-5 + positive end-expiratory pressure). It was concluded that the maneuvers have increased oxygenation, reduced atelectasis and that G2 provided better hemodynamic stability, which also corroborates the results presented in this study. Alveolar recruitment maneuver is highly important for clinical practice, since it improves oxygenation, facilitates weaning from mechanical ventilation among patients, restores the tidal volume and ventilation capacity and finally is effective in correcting pulmonary complications that are often observed in this recovery phase.<xref ref-type="bibr" rid="B24">24</xref><sup>,</sup><xref ref-type="bibr" rid="B25">25</xref>
			</p>
      <p>In this study, intermittent positive pressure breathing has also contributed to the reduction of arterial lactate levels, improvement in oxygenation rate, partial pressure of oxygen in arterial blood and oxygen saturation. These results are in accordance with Romanini et al.,<xref ref-type="bibr" rid="B26">26</xref> who carried out a randomized clinical trial with 40 patients undergoing myocardial revascularization surgery divided into two groups, patients under intermittent positive pressure breathing and respiratory incentive techniques and concluded that intermittent positive pressure breathing was more efficient, since it improved peripheral oxygen saturation and the rate of oxygen.</p>
      <p>A systematic review conducted by Silveira et al.<xref ref-type="bibr" rid="B27">27</xref> verified the effectiveness of positive pressure (intermittent positive pressure breathing, CPAP and BIPAP), conventional physiotherapy techniques and respiratory incentive techniques in the recovery of pulmonary function in patients in the postoperative period of cardiac surgery. In spite of the benefits observed, it was not possible to differ the level of evidence between the techniques, thus it is not possible to identify which technique is superior, since no study has compared the three modalities of positive pressure simultaneously.</p>
      <p>Ferreira et al.<xref ref-type="bibr" rid="B28">28</xref> revised studies between 2006 and 2011, in order to verify the superiority between the modalities of non-invasive mechanical ventilation - CPAP, BiPAP&#174;, intermittent positive pressure breathing and PSV + PEEP. Although studies are few, intermittent positive pressure breathing has proved to be more efficient in reverting hypoxemia and BiPAP in improving oxygenation levels and respiratory and cardiac frequencies compared to the other modalities. The use of lung expansion techniques increased the level of arterial oxygenation due to lungs expansion and consequently the pulmonary function, a better elimination of secretion and airway permeability, which corroborates the conclusions found in this study.</p>
      <p>Caution should be taken in the interpretation of these results, due to study limitations, such as lack of complete studies in the literature, which could have been used to compare the results, its being a before and after self-controlled study and the absence of a control group, which makes it difficult to prove the results obtained. However, the gains demonstrate the trend towards the benefits outlined here.</p>
    </sec>
    <sec sec-type="conclusions">
      <title>Conclusion</title>
      <p>The techniques of lung expansion therapy resulted in decreased arterial lactate level, improved oxygenation rate - indirectly improving partial pressure of oxygen and inspired fraction of oxygen - and peripheral oxygen saturation in the immediate postoperative period of cardiac surgery. However, new studies, preferably controlled, must be carried out to confirm these results.</p>
    </sec>
  </body>
  <back>
    <fn-group>
      <fn fn-type="financial-disclosure">
        <p>
          <bold>Sources of Funding</bold>
        </p>
        <p>This article is part of the thesis of master submitted by Silvana Souza Oliveira, Mansueto Neto e Roque Aras Junior, from Universidade Federal da Bahia - Faculdade de Medicina.</p>
      </fn>
      <fn fn-type="other">
        <p>
          <bold>Study Association</bold>
        </p>
        <p>This study is not associated with any thesis or dissertation work.</p>
      </fn>
      <fn fn-type="other">
        <label>5</label>
        <p>
          <bold>Ethics approval and consent to participate</bold>
        </p>
        <p>Trabalhos experimentais envolvendo seres humanos: This study was approved by the Ethics Committee of the Hospital Ana Nery - UFBA/SESAB under the protocol number 861.257. All the procedures in this study were in accordance with the 1975 Helsinki Declaration, updated in 2013. Informed consent was obtained from all participants included in the study.</p>
      </fn>
    </fn-group>
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  </back>
  <sub-article article-type="translation" id="s1" xml:lang="pt">
    <front-stub>
      <article-categories>
        <subj-group subj-group-type="heading">
          <subject>Artigos Originais</subject>
        </subj-group>
      </article-categories>
      <title-group>
        <article-title>Terapia de Expans&#227;o Pulmonar na Oxigena&#231;&#227;o Arterial e N&#237;vel S&#233;rico de Lactato no P&#243;s-Operat&#243;rio de Cirurgia Card&#237;aca</article-title>
      </title-group>
      <contrib-group>
        <contrib contrib-type="author">
          <name>
            <surname>Oliveira</surname>
            <given-names>Silvana Souza</given-names>
          </name>
          <xref ref-type="aff" rid="aff2"/>
          <xref ref-type="corresp" rid="c2"/>
        </contrib>
        <contrib contrib-type="author">
          <name>
            <surname>Neto</surname>
            <given-names>Mansueto</given-names>
          </name>
          <xref ref-type="aff" rid="aff2"/>
        </contrib>
        <contrib contrib-type="author">
          <name>
            <surname>Aras</surname>
            <given-names>Roque</given-names>
            <suffix>Junior</suffix>
          </name>
          <xref ref-type="aff" rid="aff2"/>
        </contrib>
        <aff id="aff2">
          <institution content-type="original">Programa de P&#243;s-gradua&#231;&#227;o em Medicina e Sa&#250;de da Universidade Federal da Bahia, Salvador, BA - Brasil</institution>
        </aff>
      </contrib-group>
      <author-notes>
        <corresp id="c2"><bold>Correspond&#234;ncia: Silvana Souza Oliveira,</bold> Rua Desembargador Gilberto Andrade, 256, Edf. Santo In&#225;cio, apt. 201. CEP: 40155200, Chame Chame, Salvador, BA - Brasil. E-mail: <email>silvanaso@oi.com.br</email>
				</corresp>
        <fn fn-type="con">
          <p>
            <bold>Contribui&#231;&#227;o dos autores</bold>
          </p>
          <p>Concep&#231;&#227;o e desenho da pesquisa: Oliveira SS, Neto M, Aras Junior R. Obten&#231;&#227;o de dados: Oliveira SS. An&#225;lise e interpreta&#231;&#227;o dos dados: Oliveira SS, Neto M. An&#225;lise estat&#237;stica: Oliveira SS, Neto M. Reda&#231;&#227;o do manuscrito: Oliveira SS, Neto M, Aras Junior R. Revis&#227;o cr&#237;tica do manuscrito quanto ao conte&#250;do intelectual importante: Oliveira SS, Neto M, Aras Junior R.</p>
        </fn>
        <fn fn-type="conflict">
          <p>
            <bold>Potencial Conflito de Interesse</bold>
          </p>
          <p>Declaro n&#227;o haver conflito de interesses pertinentes.</p>
        </fn>
      </author-notes>
      <abstract>
        <title>Resumo</title>
        <sec>
          <title>Fundamentos:</title>
          <p>Complica&#231;&#245;es cardiovasculares e pulmonares ocorrem com frequ&#234;ncia no per&#237;odo p&#243;s-operat&#243;rio imediato e podem ser prevenidas e/ou tratadas atrav&#233;s da utiliza&#231;&#227;o de t&#233;cnicas de expans&#227;o pulmonar.</p>
        </sec>
        <sec>
          <title>Objetivo:</title>
          <p>Avaliar a efic&#225;cia das t&#233;cnicas de expans&#227;o pulmonar nos n&#237;veis s&#233;ricos de lactato arterial e oxigena&#231;&#227;o de pacientes nesta fase de recupera&#231;&#227;o cir&#250;rgica.</p>
        </sec>
        <sec>
          <title>M&#233;todo:</title>
          <p>Foi realizado um estudo prospectivo e anal&#237;tico em pacientes no p&#243;s-operat&#243;rio de cirurgia card&#237;aca, est&#225;veis hemodinamicamente. Medidas de n&#237;vel de lactato e press&#227;o parcial de oxig&#234;nio foram obtidas atrav&#233;s da coleta do sangue arterial antes e ap&#243;s as t&#233;cnicas de expans&#227;o pulmonar, como manobra de recrutamento alveolar e respira&#231;&#227;o por press&#227;o positiva intermitente.</p>
        </sec>
        <sec>
          <title>Resultados:</title>
          <p>Foram inclu&#237;dos 40 pacientes com idade m&#233;dia de 51,1 &#177; 14,9 anos, sendo que 55% eram do sexo feminino. Pode-se observar diferen&#231;a estatisticamente significativa (p &lt; 0,05) na compara&#231;&#227;o dos valores do <italic>baseline</italic> e p&#243;s-interven&#231;&#227;o para o lactato arterial, &#237;ndice de oxigena&#231;&#227;o, fra&#231;&#227;o inspirada e na satura&#231;&#227;o de oxig&#234;nio em ambos os procedimentos. Para o desfecho press&#227;o arterial de oxig&#234;nio, somente o grupo que realizou respira&#231;&#227;o por press&#227;o positiva intermitente obteve melhora significativa.</p>
        </sec>
        <sec>
          <title>Conclus&#227;o:</title>
          <p>As t&#233;cnicas de expans&#227;o pulmonar utilizadas contribu&#237;ram na redu&#231;&#227;o do n&#237;vel de lactato arterial, na melhora da oxigena&#231;&#227;o e na satura&#231;&#227;o de oxig&#234;nio desta popula&#231;&#227;o, mas n&#227;o alterou o tempo de internamento na unidade de terapia intensiva.</p>
        </sec>
      </abstract>
      <kwd-group xml:lang="pt">
        <title>Palavras-chave:</title>
        <kwd>Cirurgia Tor&#225;cica</kwd>
        <kwd>Modalidades de Fisioterapia</kwd>
        <kwd>Cuidados P&#243;s-Operat&#243;rios</kwd>
        <kwd>Oxigena&#231;&#227;o</kwd>
        <kwd>N&#237;vel de Oxig&#234;nio</kwd>
        <kwd>L-Lactato Desidrogenase</kwd>
      </kwd-group>
    </front-stub>
    <body>
      <sec sec-type="intro">
        <title>Introdu&#231;&#227;o</title>
        <p>As doen&#231;as cardiovasculares est&#227;o entre as principais causas de morbimortalidade no mundo, envolvendo grandes investimentos financeiros e comprometendo a sa&#250;de da popula&#231;&#227;o. As estrat&#233;gias terap&#234;uticas incluem preven&#231;&#227;o, medica&#231;&#245;es, interven&#231;&#245;es endovasculares e cirurgias card&#237;acas.<xref ref-type="bibr" rid="B1">1</xref> As cirurgias card&#237;acas, notadamente as revasculariza&#231;&#245;es e troca de v&#225;lvulas, modificaram a expectativa de vida de pacientes melhorando sua sobrevida e qualidade de vida.<xref ref-type="bibr" rid="B2">2</xref>
				</p>
        <p>Apesar dos benef&#237;cios evidentes encontrados na realiza&#231;&#227;o das cirurgias card&#237;acas, complica&#231;&#245;es cardiovasculares e pulmonares ocorrem frequentemente no per&#237;odo p&#243;s-operat&#243;rio imediato, comprometendo a evolu&#231;&#227;o dos pacientes com redu&#231;&#227;o da oxigena&#231;&#227;o e aumento dos n&#237;veis de lactato arterial pela hipoperfus&#227;o tecidual, hipoxemia e <italic>shunt</italic> intrapulmonar, aumentando o tempo de internamento, podendo levar a morte.<xref ref-type="bibr" rid="B3">3</xref><sup>-</sup><xref ref-type="bibr" rid="B6">6</xref>
				</p>
        <p>As complica&#231;&#245;es pulmonares podem causar desvio para o metabolismo anaer&#243;bico com acidose metab&#243;lica, eleva&#231;&#227;o no n&#237;vel de lactato e preju&#237;zo na circula&#231;&#227;o microvascular,<xref ref-type="bibr" rid="B7">7</xref><sup>-</sup><xref ref-type="bibr" rid="B10">10</xref> que podem ser prevenidos ou resolvidos atrav&#233;s da utiliza&#231;&#227;o de t&#233;cnicas de expans&#227;o pulmonar, promovendo a eleva&#231;&#227;o dos volumes e capacidades pulmonares, atrav&#233;s do aumento do gradiente de press&#227;o transpulmonar e assim revert&#234;-las, estando o paciente em ventila&#231;&#227;o mec&#226;nica ou respirando ao ar ambiente.<xref ref-type="bibr" rid="B11">11</xref>
				</p>
        <p>Dentre as t&#233;cnicas de expans&#227;o pulmonar, temos a manobra de recrutamento alveolar para pacientes conectados ao ventilador mec&#226;nico, que tem a finalidade de melhorar a oxigena&#231;&#227;o, de reduzir as les&#245;es provocadas pelo ventilador mec&#226;nico e de facilitar o desmame e a extuba&#231;&#227;o,<xref ref-type="bibr" rid="B12">12</xref> al&#233;m da respira&#231;&#227;o por press&#227;o positiva intermitente para pacientes com respira&#231;&#227;o espont&#226;nea, com objetivo de aumentar o volume corrente, melhorar as trocas gasosas e o direcionamento do ar para &#225;reas de hipoventila&#231;&#227;o.<xref ref-type="bibr" rid="B13">13</xref><sup>,</sup><xref ref-type="bibr" rid="B14">14</xref>
				</p>
        <p>Apesar dos estudos que evidenciam os efeitos significativos das t&#233;cnicas de expans&#227;o pulmonar para pacientes com doen&#231;a pulmonar, s&#227;o escassos estudos que testaram a utiliza&#231;&#227;o da t&#233;cnica em pacientes com doen&#231;a card&#237;aca, sobretudo no p&#243;s-operat&#243;rio de cirurgia card&#237;aca. Desta forma, o objetivo deste estudo foi avaliar os efeitos das t&#233;cnicas de expans&#227;o pulmonar nos n&#237;veis de lactato arterial e oxigena&#231;&#227;o de pacientes em p&#243;s-operat&#243;rio imediato de cirurgia card&#237;aca.</p>
      </sec>
      <sec sec-type="methods">
        <title>M&#233;todos</title>
        <p>Foi realizado um estudo prospectivo e anal&#237;tico, na unidade de p&#243;s-operat&#243;rio de cirurgia card&#237;aca do Hospital Ana Nery, da UFBA/SESAB, centro de refer&#234;ncia em tratamento de doen&#231;as cardiovasculares do estado da Bahia.</p>
        <p>Incluiu pacientes com idade maior que 18 anos, est&#225;veis hemodinamicamente, press&#227;o arterial m&#233;dia maior ou igual a 60 mmHg e que necessitaram, com a sua evolu&#231;&#227;o cl&#237;nica, da aplica&#231;&#227;o de t&#233;cnicas de expans&#227;o pulmonar. Foram exclu&#237;dos os pacientes que apresentaram: agita&#231;&#227;o psicomotora, hipertens&#227;o intracraniana, hipertens&#227;o pulmonar, pneumopatia e/ou pneumectomia pr&#233;via, doen&#231;a pulmonar obstrutiva cr&#244;nica, pneumot&#243;rax n&#227;o drenado, pneumomediastino, hemoptise, redu&#231;&#227;o no d&#233;bito card&#237;aco e em uso do bal&#227;o intra-a&#243;rtico, &#237;ndice de massa corp&#243;rea maior que 30 Kg/m<sup>2</sup>. O projeto foi aprovado pelo Comit&#234; de &#201;tica do Hospital Ana Nery - UFBA/SESAB, sob protocolo de n&#250;mero 861.257.</p>
        <p>Foram coletadas medidas de n&#237;vel de lactato e press&#227;o parcial de oxig&#234;nio no sangue arterial, fra&#231;&#227;o inspirada e a satura&#231;&#227;o de oxig&#234;nio, pr&#233; e p&#243;s-interven&#231;&#227;o das t&#233;cnicas de expans&#227;o pulmonar, com a finalidade de verificar a varia&#231;&#227;o do n&#237;vel de lactato arterial e do &#237;ndice de oxigena&#231;&#227;o em consequ&#234;ncia da aplica&#231;&#227;o dessas t&#233;cnicas nesta fase de recupera&#231;&#227;o.</p>
        <p>Par&#226;metros cl&#237;nicos, cir&#250;rgicos, laboratoriais e hemodin&#226;micos como: frequ&#234;ncia card&#237;aca e a press&#227;o arterial m&#233;dia foram monitorizados atrav&#233;s da an&#225;lise de um monitor multiparam&#233;trico (Portal DX2020 DIXTAL&#174;); a press&#227;o parcial de oxig&#234;nio no sangue arterial, o lactato, a fra&#231;&#227;o inspirada e a satura&#231;&#227;o de oxig&#234;nio, atrav&#233;s do exame da hemogasometria arterial (Roche COBAS b20&#174;), ap&#243;s a chegada na unidade p&#243;s-cir&#250;rgica, ou enquanto o paciente permanecia em ventila&#231;&#227;o mec&#226;nica invasiva, a cada seis horas, como foi padronizado para esta unidade de terapia intensiva. A rela&#231;&#227;o de oxigena&#231;&#227;o foi calculado dividindo a press&#227;o parcial de oxig&#234;nio no sangue arterial pela fra&#231;&#227;o inspirada de oxig&#234;nio, conforme com o III Consenso Brasileiro de Ventila&#231;&#227;o Mec&#226;nica.<xref ref-type="bibr" rid="B15">15</xref> Na ficha de controle da anestesia coletou-se o tempo de clampeamento da aorta ou tempo de an&#243;xia, de circula&#231;&#227;o extracorp&#243;rea e de anestesia total, a cirurgia realizada e se o paciente foi submetido &#224; expans&#227;o vol&#234;mica ap&#243;s a sua admiss&#227;o na unidade p&#243;s cir&#250;rgica.</p>
        <p>No protocolo de ventila&#231;&#227;o mec&#226;nica, todos os pacientes foram admitidos no modo de ventila&#231;&#227;o com volume controlado - VCV, com fra&#231;&#227;o inspirada de oxig&#234;nio de 0,6 (60%), press&#227;o positiva expirat&#243;ria final de 5 cmH<sub>2</sub>O, freq&#252;&#234;ncia respirat&#243;ria de 12 a 20 rpm e volume corrente variando de 6 a 8 ml/Kg. Ap&#243;s o resultado da primeira hemogasometria, o modo ventilat&#243;rio era alterado para ventila&#231;&#227;o controlada por press&#227;o - PCV, com fluxo inspirat&#243;rio de 40 a 50 l/min decrescente, pausa inspirat&#243;ria de 0,2 segundos, frequ&#234;ncia respirat&#243;ria de 12 a 15 rpm, press&#227;o positiva expirat&#243;ria final de 5 cmH<sub>2</sub>O. Se a rela&#231;&#227;o press&#227;o parcial de oxig&#234;nio no sangue arterial dividida pela fra&#231;&#227;o inspirada de oxig&#234;nio fosse menor que 200, a press&#227;o positiva expirat&#243;ria final deveria ser elevada para 8 cmH<sub>2</sub>O e a fra&#231;&#227;o inspirada de oxig&#234;nio para 0,6 (60%). Para proceder &#224; extuba&#231;&#227;o, o modo foi ventila&#231;&#227;o com press&#227;o de suporte - PSV, e depois todos os pacientes receberam oxig&#234;nio suplementar via cateter nasal, fisioterapia respirat&#243;ria e motora, incluindo exerc&#237;cio de tosse.</p>
        <p>As t&#233;cnicas de expans&#227;o pulmonar utilizadas foram: a manobra de recrutamento alveolar ou a respira&#231;&#227;o por press&#227;o positiva intermitente, realizadas atrav&#233;s do ventilador mec&#226;nico <italic>MAQUET</italic> modelo <italic>Servos</italic>
					<sup>&#174;</sup> ou do VELA <italic>TBird Series</italic>
					<sup>&#174;</sup>. Foram escolhidos por ser o procedimento operacional do hospital, e conforme a maneira como s&#227;o realizados na unidade p&#243;s- cir&#250;rgica. Quinze minutos antes e ap&#243;s qualquer procedimento de t&#233;cnicas de expans&#227;o pulmonar, coletou-se sangue arterial para a realiza&#231;&#227;o da hemogasometria, com a finalidade de avaliar a dosagem do n&#237;vel de lactato e a oxigena&#231;&#227;o. Cada indiv&#237;duo foi comparado com ele mesmo, antes e ap&#243;s procedimento pelo exame da hemogasometria.</p>
        <p>A escolha do procedimento das t&#233;cnicas de expans&#227;o pulmonar a serem aplicadas e a conduta do fisioterapeuta dependeram da evolu&#231;&#227;o e da condi&#231;&#227;o respirat&#243;ria do paciente, verificadas atrav&#233;s do resultado da hemogasometria e da radiografia dos pulm&#245;es. Se o paciente estivesse ligado ao ventilador mec&#226;nico, a t&#233;cnica aplicada era a manobra de recrutamento alveolar, ao ar ambiente, realizada a respira&#231;&#227;o por press&#227;o positiva intermitente.</p>
        <p>Manobra de recrutamento alveolar era aplicada caso o paciente tivesse apresentado uma rela&#231;&#227;o press&#227;o parcial de oxig&#234;nio no sangue arterial, dividida pela fra&#231;&#227;o inspirada de oxig&#234;nio, maior ou igual a 201 ou menor que 250, antes de ser extubado. O ventilador mec&#226;nico foi ajustado em modo ventila&#231;&#227;o com press&#227;o controlada, PCV,<xref ref-type="bibr" rid="B16">16</xref><sup>,</sup><xref ref-type="bibr" rid="B17">17</xref> press&#227;o positiva expirat&#243;ria final de 25 cmH<sub>2</sub>O,<xref ref-type="bibr" rid="B18">18</xref><sup>,</sup><xref ref-type="bibr" rid="B19">19</xref> abaixo do que &#233; recomendado pelo III Consenso Brasileiro de Ventila&#231;&#227;o Mec&#226;nica,<xref ref-type="bibr" rid="B15">15</xref> para seguran&#231;a da mesma e preven&#231;&#227;o do colapso alveolar durante a fase expirat&#243;ria<xref ref-type="bibr" rid="B18">18</xref> - de maneira cont&#237;nua a partir da press&#227;o positiva expirat&#243;ria final basal, com incremento de 5 cmH<sub>2</sub>O por 20 segundos, at&#233; atingir o valor determinado da press&#227;o positiva expirat&#243;ria final.<xref ref-type="bibr" rid="B18">18</xref> A press&#227;o inspirat&#243;ria de 15 cmH<sub>2</sub>O foi realizada em tr&#234;s ciclos por 40 segundos.<xref ref-type="bibr" rid="B6">6</xref><sup>,</sup><xref ref-type="bibr" rid="B20">20</xref><sup>,</sup><xref ref-type="bibr" rid="B21">21</xref> Nos intervalos de um minuto entre cada ciclo a press&#227;o positiva expirat&#243;ria final retornou a 15 cmH<sub>2</sub>O de forma decrescente.<xref ref-type="bibr" rid="B21">21</xref> Ao final do procedimento realizou-se uma nova avalia&#231;&#227;o de forma completa. Foram observados e anotados os resultados obtidos. Al&#233;m disso, todos os pacientes voltaram para uma press&#227;o positiva expirat&#243;ria final 2 cmH<sub>2</sub>O, acima da press&#227;o positiva expirat&#243;ria final antes do recrutamento inicial.</p>
        <p>Respira&#231;&#227;o por press&#227;o positiva intermitente foi realizada com o paciente em respira&#231;&#227;o espont&#226;nea e caso necessitasse de reexpans&#227;o pulmonar, de acordo com o exame f&#237;sico e do resultado da radiografia dos pulm&#245;es. O paciente foi sentado em 90 graus, avaliado e orientado sobre o procedimento. O ventilador mec&#226;nico foi ajustado com press&#227;o inspirat&#243;ria de 10 cmH<sub>2</sub>O e press&#227;o positiva expirat&#243;ria final de 15 cmH<sub>2</sub>O, com uso de m&#225;scara facial. Foram realizados tr&#234;s ciclos de dois minutos com intervalo de um minuto entre os ciclos, uma vez a cada turno. Ao final do mesmo foi realizada uma nova avalia&#231;&#227;o de forma completa, observados e anotados os resultados obtidos.</p>
        <p>Todos os pacientes foram avaliados antes, durante e ap&#243;s qualquer interven&#231;&#227;o de t&#233;cnicas de expans&#227;o pulmonar realizada. Desta maneira, a coleta de dados era interrompida, caso o paciente apresentasse instabilidade hemodin&#226;mica, observada no monitor multiparam&#233;trico. Durante a realiza&#231;&#227;o de qualquer procedimento de t&#233;cnicas de expans&#227;o pulmonar, as instabilidades hemodin&#226;micas consideradas foram: queda no valor da press&#227;o arterial m&#233;dia inferior a 60 mmHg ou da satura&#231;&#227;o perif&#233;rica de oxig&#234;nio inferior a 90% e se a sua frequ&#234;ncia card&#237;aca aumentasse ou diminu&#237;sse em 30% do valor da avalia&#231;&#227;o realizada antes da execu&#231;&#227;o das manobras.</p>
        <sec>
          <title>An&#225;lise Estat&#237;stica</title>
          <p>Os resultados referentes &#224;s coletas foram armazenados em tabelas no <italic>software Microsoft Exc</italic>el&#174; (<italic>Microsoft Corporation, Mountain View, CA, EUA</italic>, vers&#227;o 2003). Para a an&#225;lise dos dados demogr&#225;ficos e cl&#237;nicos, foi utilizada estat&#237;stica descritiva. Os dados de vari&#225;veis cont&#237;nuas foram analisados com medidas de tend&#234;ncia central e dispers&#227;o, expressos como m&#233;dia e desvio-padr&#227;o, devido a serem param&#233;tricos. Os dados de vari&#225;veis dicot&#244;micas ou categ&#243;ricas foram analisados com medidas de freq&#252;&#234;ncia e expressos como porcentagens. Para compara&#231;&#227;o dos per&#237;odos antes e depois, foi calculada a normalidade dos dados por meio do teste de normalidade. Depois foi escolhido o teste T de compara&#231;&#227;o em pares, sendo levado em considera&#231;&#227;o o n&#237;vel de signific&#226;ncia de 5%. A an&#225;lise dos dados foi realizada com o <italic>software Statistical Package for Social Science</italic> (SPSS) <italic>for Windows</italic> (<italic>SPSS Inc., Chicago, IL, EUA</italic>, vers&#227;o 20 ou superior).</p>
        </sec>
      </sec>
      <sec sec-type="results">
        <title>Resultados</title>
        <p>Foram inclu&#237;dos 40 pacientes por conveni&#234;ncia admitidos na unidade p&#243;s-cir&#250;rgica, que necessitaram, de acordo com a sua evolu&#231;&#227;o cl&#237;nica e condi&#231;&#227;o respirat&#243;ria, da aplica&#231;&#227;o de: manobra de recrutamento alveolar, utilizada em 18 pacientes, ou de respira&#231;&#227;o por press&#227;o positiva intermitente, aplicada em 22 indiv&#237;duos. Nenhum paciente necessitou da aplica&#231;&#227;o das duas t&#233;cnicas, mesmo em momentos diferentes do per&#237;odo da sua recupera&#231;&#227;o. A descri&#231;&#227;o das caracter&#237;sticas demogr&#225;ficas e cl&#237;nicas encontram-se na <xref ref-type="table" rid="t5">tabela 1</xref>.</p>
        <table-wrap id="t5">
          <label>Tabela 1</label>
          <caption>
            <title>Caracteriza&#231;&#227;o de toda a amostra estudada. n = 40 pacientes</title>
          </caption>
          <table frame="hsides" rules="groups">
            <colgroup>
              <col width="33%"/>
              <col width="33%"/>
              <col width="33%"/>
            </colgroup>
            <thead>
              <tr>
                <th align="left" style="background-color:#C5C6C8">
								</th>
                <th align="center" style="background-color:#C5C6C8">M&#233;dia &#177; Desvio Padr&#227;o</th>
                <th align="center" style="background-color:#C5C6C8">Frequ&#234;ncia(%)</th>
              </tr>
            </thead>
            <tbody>
              <tr>
                <td align="left">Idade (anos)</td>
                <td align="center">51,1 &#177; 14.9</td>
                <td align="center">--</td>
              </tr>
              <tr>
                <td align="left">G&#234;nero (feminino)</td>
                <td align="center">--</td>
                <td align="center">22 (55%)</td>
              </tr>
              <tr>
                <td align="left">IMC (Kg/m<sup>2</sup>)<xref ref-type="table-fn" rid="TFN9">*</xref>
								</td>
                <td align="center">24,4 &#177; 4.3</td>
                <td align="center">--</td>
              </tr>
              <tr>
                <td align="left">
                  <bold>Estado Civil</bold>
                </td>
                <td align="center">
								</td>
                <td align="center">
								</td>
              </tr>
              <tr>
                <td align="left">Solteiro</td>
                <td align="center">--</td>
                <td align="center">13 (32,5%)</td>
              </tr>
              <tr>
                <td align="left">Casado</td>
                <td align="center">--</td>
                <td align="center">23 (57,5%)</td>
              </tr>
              <tr>
                <td align="left">Divorciado</td>
                <td align="center">--</td>
                <td align="center">3 (7,5%)</td>
              </tr>
              <tr>
                <td align="left">Vi&#250;vo</td>
                <td align="center">--</td>
                <td align="center">1 (2,5%)</td>
              </tr>
              <tr>
                <td align="left">N&#227;o Diab&#233;tico</td>
                <td align="center">--</td>
                <td align="center">32 (80%)</td>
              </tr>
              <tr>
                <td align="left">N&#227;o Tabagista</td>
                <td align="center">--</td>
                <td align="center">24 (60%)</td>
              </tr>
              <tr>
                <td align="left">Fra&#231;&#227;o de Eje&#231;&#227;o do VE (%)<xref ref-type="table-fn" rid="TFN10">&#8224;</xref>
								</td>
                <td align="center">59,6 &#177; 9.7</td>
                <td align="center">--</td>
              </tr>
            </tbody>
          </table>
          <table-wrap-foot>
            <fn id="TFN9">
              <label>*</label>
              <p>IMC: &#237;ndice de massa corp&#243;rea;</p>
            </fn>
            <fn id="TFN10">
              <label>&#8224;</label>
              <p>VE: ventr&#237;culo esquerdo</p>
            </fn>
          </table-wrap-foot>
        </table-wrap>
        <p>A t&#233;cnica de manobra de recrutamento alveolar foi utilizada em 18 pacientes e a de respira&#231;&#227;o por press&#227;o positiva intermitente foi aplicada em 22 pacientes. Nas <xref ref-type="table" rid="t6">tabelas 2</xref> e <xref ref-type="table" rid="t7">3</xref> est&#227;o descritas as caracter&#237;sticas demogr&#225;ficas e cl&#237;nicas, respectivamente.</p>
        <table-wrap id="t6">
          <label>Tabela 2</label>
          <caption>
            <title>Caracter&#237;stica dos 18 pacientes que realizaram a Manobra de Recrutamento Alveolar (MRA)</title>
          </caption>
          <table frame="hsides" rules="groups">
            <colgroup>
              <col width="33%"/>
              <col width="33%"/>
              <col width="33%"/>
            </colgroup>
            <thead>
              <tr>
                <th align="left" style="background-color:#C5C6C8">
								</th>
                <th align="center" style="background-color:#C5C6C8">M&#233;dia &#177; Desvio Padr&#227;o</th>
                <th align="center" style="background-color:#C5C6C8">Frequ&#234;ncia(%)</th>
              </tr>
            </thead>
            <tbody>
              <tr>
                <td align="left">Idade (anos)</td>
                <td align="center">49,6 &#177; 16,8</td>
                <td align="center">--</td>
              </tr>
              <tr>
                <td align="left">G&#234;nero (feminino)</td>
                <td align="center">--</td>
                <td align="center">8 (42,1%)</td>
              </tr>
              <tr>
                <td align="left">IMC (Kg/m<sup>2</sup>)<xref ref-type="table-fn" rid="TFN11">*</xref>
								</td>
                <td align="center">23,2 &#177; 4,1</td>
                <td align="center">--</td>
              </tr>
              <tr>
                <td align="left">
                  <bold>Estado Civil</bold>
                </td>
                <td align="center">
								</td>
                <td align="center">
								</td>
              </tr>
              <tr>
                <td align="left">Solteiro</td>
                <td align="center">--</td>
                <td align="center">4 (21,1%)</td>
              </tr>
              <tr>
                <td align="left">Casado</td>
                <td align="center">--</td>
                <td align="center">10 (52,6%)</td>
              </tr>
              <tr>
                <td align="left">Divorciado</td>
                <td align="center">--</td>
                <td align="center">3 (15,8%)</td>
              </tr>
              <tr>
                <td align="left">Vi&#250;vo</td>
                <td align="center">--</td>
                <td align="center">1 (5,3%)</td>
              </tr>
              <tr>
                <td align="left">N&#227;o Diab&#233;tico</td>
                <td align="center">--</td>
                <td align="center">17 (89,5%)</td>
              </tr>
              <tr>
                <td align="left">N&#227;o Tabagista</td>
                <td align="center">--</td>
                <td align="center">10 (52,6%)</td>
              </tr>
              <tr>
                <td align="left">Fra&#231;&#227;o de Eje&#231;&#227;o do Ventr&#237;culo Esquerdo (%)</td>
                <td align="center">61,1 &#177; 7,7</td>
                <td align="center">--</td>
              </tr>
              <tr>
                <td align="left">
                  <bold>Cirurgia Realizada</bold>
                </td>
                <td align="center">
								</td>
                <td align="center">
								</td>
              </tr>
              <tr>
                <td align="left">Troca de Valva Mitral</td>
                <td align="center">--</td>
                <td align="center">3 (15,8%)</td>
              </tr>
              <tr>
                <td align="left">Troca de Valva A&#243;rtica</td>
                <td align="center">--</td>
                <td align="center">1 (5,3%)</td>
              </tr>
              <tr>
                <td align="left">Dupla Troca Valvar</td>
                <td align="center">--</td>
                <td align="center">5 (26,3%)</td>
              </tr>
              <tr>
                <td align="left">Revasculariza&#231;&#227;o do Mioc&#225;rdio</td>
                <td align="center">--</td>
                <td align="center">5 (26,3%)</td>
              </tr>
              <tr>
                <td align="left">Troca de Valva A&#243;rtica + Revasculariza&#231;&#227;o do Mioc&#225;rdio</td>
                <td align="center">--</td>
                <td align="center">2 (10,5%)</td>
              </tr>
              <tr>
                <td align="left">Troca de Valva Mitral + Revasculariza&#231;&#227;o do Mioc&#225;rdio</td>
                <td align="center">--</td>
                <td align="center">1 (5,3%)</td>
              </tr>
              <tr>
                <td align="left">Tetralogia de Fallot</td>
                <td align="center">--</td>
                <td align="center">1 (5,3%)</td>
              </tr>
              <tr>
                <td align="left">
                  <bold>Tempos de</bold>
                </td>
                <td align="center">
								</td>
                <td align="center">
								</td>
              </tr>
              <tr>
                <td align="left">Cirurgia (horas)</td>
                <td align="center">5,9 &#177; 1,1</td>
                <td align="center">--</td>
              </tr>
              <tr>
                <td align="left">An&#243;xia (minutos)</td>
                <td align="center">87,3 &#177; 42,4</td>
                <td align="center">--</td>
              </tr>
              <tr>
                <td align="left">CEC (minutos)<xref ref-type="table-fn" rid="TFN12">&#8224;</xref>
								</td>
                <td align="center">118,3 &#177; 54,8</td>
                <td align="center">--</td>
              </tr>
              <tr>
                <td align="left">Perman&#234;ncia na UPC (dias)<xref ref-type="table-fn" rid="TFN13">&#8225;</xref>
								</td>
                <td align="center">5,2 &#177; 6,9</td>
                <td align="center">--</td>
              </tr>
            </tbody>
          </table>
          <table-wrap-foot>
            <fn id="TFN11">
              <label>*</label>
              <p>IMC: &#237;ndice de massa corp&#243;rea;</p>
            </fn>
            <fn id="TFN12">
              <label>&#8224;</label>
              <p>CEC: Circula&#231;&#227;o extra corp&#243;rea;</p>
            </fn>
            <fn id="TFN13">
              <label>&#8225;</label>
              <p>UPC: Unidade P&#243;s Cir&#250;rgica.</p>
            </fn>
          </table-wrap-foot>
        </table-wrap>
        <table-wrap id="t7">
          <label>Tabela 3</label>
          <caption>
            <title>Caracter&#237;stica dos 22 pacientes que realizaram a Respira&#231;&#227;o por Press&#227;o Positiva Intermitente (RPPI)</title>
          </caption>
          <table frame="hsides" rules="groups">
            <colgroup>
              <col width="33%"/>
              <col width="33%"/>
              <col width="33%"/>
            </colgroup>
            <thead>
              <tr>
                <th align="left" style="background-color:#C5C6C8">
								</th>
                <th align="center" style="background-color:#C5C6C8">M&#233;dia &#177; Desvio Padr&#227;o</th>
                <th align="center" style="background-color:#C5C6C8">Frequ&#234;ncia(%)</th>
              </tr>
            </thead>
            <tbody>
              <tr>
                <td align="left">Idade (anos)</td>
                <td align="center">52,3 &#177; 13,6</td>
                <td align="center">--</td>
              </tr>
              <tr>
                <td align="left">G&#234;nero (feminino)</td>
                <td align="center">--</td>
                <td align="center">14 (46,7%)</td>
              </tr>
              <tr>
                <td align="left">IMC (Kg/m<sup>2</sup>)<xref ref-type="table-fn" rid="TFN14">*</xref>
								</td>
                <td align="center">25,4 &#177; 4,4</td>
                <td align="center">--</td>
              </tr>
              <tr>
                <td align="left">
                  <bold>Estado Civil</bold>
                </td>
                <td align="center">
								</td>
                <td align="center">
								</td>
              </tr>
              <tr>
                <td align="left">Solteiro</td>
                <td align="center">--</td>
                <td align="center">9 (30%)</td>
              </tr>
              <tr>
                <td align="left">Casado</td>
                <td align="center">--</td>
                <td align="center">13 (43,3%)</td>
              </tr>
              <tr>
                <td align="left">N&#227;o Diab&#233;tico</td>
                <td align="center">--</td>
                <td align="center">15 (50%)</td>
              </tr>
              <tr>
                <td align="left">N&#227;o Tabagista</td>
                <td align="center">--</td>
                <td align="center">19 (63,3%)</td>
              </tr>
              <tr>
                <td align="left">Fra&#231;&#227;o de Eje&#231;&#227;o do Ventr&#237;culo Esquerdo (%)</td>
                <td align="center">58,5 &#177; 11,2</td>
                <td align="center">--</td>
              </tr>
              <tr>
                <td align="left">
                  <bold>Cirurgia Realizada</bold>
                </td>
                <td align="center">
								</td>
                <td align="center">
								</td>
              </tr>
              <tr>
                <td align="left">Troca de Valva Mitral</td>
                <td align="center">--</td>
                <td align="center">5 (16,7%)</td>
              </tr>
              <tr>
                <td align="left">Troca de Valva A&#243;rtica</td>
                <td align="center">--</td>
                <td align="center">2 (6,7%)</td>
              </tr>
              <tr>
                <td align="left">Dupla Troca valvar</td>
                <td align="center">--</td>
                <td align="center">4 (13,3%)</td>
              </tr>
              <tr>
                <td align="left">Revasculariza&#231;&#227;o do Mioc&#225;rdio</td>
                <td align="center">--</td>
                <td align="center">9 (30%)</td>
              </tr>
              <tr>
                <td align="left">Troca de Valva A&#243;rtica + Revasculariza&#231;&#227;o do Mioc&#225;rdio</td>
                <td align="center">--</td>
                <td align="center">1 (3,3%)</td>
              </tr>
              <tr>
                <td align="left">Dupla Troca Valvar + Comunica&#231;&#227;o Inter Atrial</td>
                <td align="center">--</td>
                <td align="center">1 (3,3%)</td>
              </tr>
              <tr>
                <td align="left">
                  <bold>Tempos de</bold>
                </td>
                <td align="center">
								</td>
                <td align="center">
								</td>
              </tr>
              <tr>
                <td align="left">Cirurgia</td>
                <td align="center">5,6 &#177; 0,8</td>
                <td align="center">--</td>
              </tr>
              <tr>
                <td align="left">An&#243;xia (minutos)</td>
                <td align="center">76,1 &#177; 31,2</td>
                <td align="center">--</td>
              </tr>
              <tr>
                <td align="left">CEC (minutos)<xref ref-type="table-fn" rid="TFN15">&#8224;</xref>
								</td>
                <td align="center">90,3 &#177; 33,3</td>
                <td align="center">--</td>
              </tr>
              <tr>
                <td align="left">Perman&#234;ncia na UPC (dias)<xref ref-type="table-fn" rid="TFN16">&#8225;</xref>
								</td>
                <td align="center">3,3 &#177; 1,8</td>
                <td align="center">--</td>
              </tr>
            </tbody>
          </table>
          <table-wrap-foot>
            <fn id="TFN14">
              <label>*</label>
              <p>IMC: &#237;ndice de massa corp&#243;rea;</p>
            </fn>
            <fn id="TFN15">
              <label>&#8224;</label>
              <p>CEC: Circula&#231;&#227;o extra corp&#243;rea;</p>
            </fn>
            <fn id="TFN16">
              <label>&#8225;</label>
              <p>UPC: Unidade P&#243;s Cir&#250;rgica</p>
            </fn>
          </table-wrap-foot>
        </table-wrap>
        <p>Na <xref ref-type="table" rid="t8">tabela 4</xref>, est&#227;o descritos os valores basais e p&#243;s-interven&#231;&#227;o dos grupos manobra de recrutamento alveolar e respira&#231;&#227;o por press&#227;o positiva intermitente, para as seguintes vari&#225;veis: lactato arterial, &#237;ndice de oxigena&#231;&#227;o, press&#227;o parcial de oxig&#234;nio no sangue arterial, fra&#231;&#227;o inspirada e na satura&#231;&#227;o de oxig&#234;nio. Pode-se observar diferen&#231;a estat&#237;sticamente significativa na compara&#231;&#227;o dos valores do <italic>baseline</italic> e p&#243;s-interven&#231;&#227;o para ambos os procedimentos, em todas vari&#225;veis, com exce&#231;&#227;o da vari&#225;vel Press&#227;o Parcial de Oxig&#234;nio no sangue arterial para o grupo manobra de recrutamento alveolar.</p>
        <table-wrap id="t8">
          <label>Tabela 4</label>
          <caption>
            <title>M&#233;dia, desvio padr&#227;o e valor de p antes e depois das t&#233;cnicas de: manobra de recrutamento alveolar (MRA) com n = 18 e de respira&#231;&#227;o por press&#227;o positiva intermitente (RPPI), n = 22</title>
          </caption>
          <table frame="hsides" rules="groups">
            <colgroup>
              <col width="20%"/>
              <col width="20%"/>
              <col width="20%"/>
              <col width="20%"/>
              <col width="20%"/>
            </colgroup>
            <thead>
              <tr>
                <th align="left" rowspan="2" style="background-color:#C5C6C8">
								</th>
                <th align="center" rowspan="2" style="background-color:#C5C6C8">
								</th>
                <th align="center" style="border-bottom-width:thin;border-bottom-style:solid;background-color:#C5C6C8">Avalia&#231;&#227;o Pr&#233;</th>
                <th align="center" style="border-bottom-width:thin;border-bottom-style:solid;background-color:#C5C6C8">Avalia&#231;&#227;o P&#243;s</th>
                <th align="center" rowspan="2" style="background-color:#C5C6C8">p valor</th>
              </tr>
              <tr>
                <th align="center" style="background-color:#C5C6C8">M&#233;dia &#177; Desvio Padr&#227;o</th>
                <th align="center" style="background-color:#C5C6C8">M&#233;dia &#177; Desvio Padr&#227;o</th>
              </tr>
            </thead>
            <tbody>
              <tr>
                <td align="left" rowspan="2">Lactato Arterial (mmol/L)</td>
                <td align="center">MRA</td>
                <td align="center">5,7 &#177; 2,4</td>
                <td align="center">3,8 &#177; 1,6 </td>
                <td align="center">0,002</td>
              </tr>
              <tr>
                <td align="center">RPPI</td>
                <td align="center">3,4 &#177; 0,9</td>
                <td align="center">2,0 &#177; 0,7</td>
                <td align="center">&#8804; 0</td>
              </tr>
              <tr>
                <td align="left" rowspan="2">&#205;ndice de Oxigena&#231;&#227;o (mmHg)</td>
                <td align="center">MRA</td>
                <td align="center">287,4 &#177; 121,3</td>
                <td align="center">432,0 &#177; 186,3</td>
                <td align="center">0,005</td>
              </tr>
              <tr>
                <td align="center">RPPI</td>
                <td align="center">337,4 &#177; 133,9</td>
                <td align="center">513,6 &#177; 198,8</td>
                <td align="center">&#8804; 0</td>
              </tr>
              <tr>
                <td align="left" rowspan="2">Press&#227;o de Oxig&#234;nio (mmHg)</td>
                <td align="center">MRA</td>
                <td align="center">123,6 &#177; 34,4</td>
                <td align="center">132,1 &#177; 54,1</td>
                <td align="center">0,579</td>
              </tr>
              <tr>
                <td align="center">RPPI</td>
                <td align="center">94,2 &#177; 31,6</td>
                <td align="center">108,8 &#177; 41,0</td>
                <td align="center">= 0,016</td>
              </tr>
              <tr>
                <td align="left" rowspan="2">Fra&#231;&#227;o Inspirada (%)</td>
                <td align="center">MRA</td>
                <td align="center">46,1 &#177; 10,9</td>
                <td align="center">31,5 &#177; 6,7</td>
                <td align="center">&#8804; 0</td>
              </tr>
              <tr>
                <td align="center">RPPI</td>
                <td align="center">31,7 &#177; 16,9</td>
                <td align="center">21,3 &#177; 0,9</td>
                <td align="center">= 0,008</td>
              </tr>
              <tr>
                <td align="left" rowspan="2">Satura&#231;&#227;o de Oxig&#234;nio (%)</td>
                <td align="center">MRA</td>
                <td align="center">96,4 &#177; 2,1</td>
                <td align="center">98,5 &#177; 1,1</td>
                <td align="center">&#8804; 0</td>
              </tr>
              <tr>
                <td align="center">RPPI</td>
                <td align="center">95,6 &#177; 1,5</td>
                <td align="center">98,0 &#177; 0,8</td>
                <td align="center">&#8804; 0</td>
              </tr>
            </tbody>
          </table>
        </table-wrap>
      </sec>
      <sec sec-type="discussion">
        <title>Discuss&#227;o</title>
        <p>Os resultados encontrados neste estudo permitem concluir que os procedimentos de t&#233;cnicas de expans&#227;o pulmonar contribu&#237;ram na redu&#231;&#227;o do n&#237;vel de lactato arterial e na melhora da oxigena&#231;&#227;o dos pacientes no p&#243;s-operat&#243;rio de cirurgia card&#237;aca. Atribu&#237;mos os nossos resultados &#224; expans&#227;o das vias a&#233;reas e dos alv&#233;olos provocada pelo uso da press&#227;o positiva, que promoveu uma melhor ventila&#231;&#227;o das &#225;reas que antes eram colapsadas.</p>
        <p>A manobra de recrutamento alveolar proporciona uma melhora na distribui&#231;&#227;o do g&#225;s alveolar, maximizando as trocas gasosas e melhorando a oxigena&#231;&#227;o arterial.<xref ref-type="bibr" rid="B22">22</xref> Foi observado que esta t&#233;cnica contribuiu para a redu&#231;&#227;o do n&#237;vel de lactato no sangue arterial. Auler Jr et al.<xref ref-type="bibr" rid="B23">23</xref> realizaram um estudo prospectivo com 40 pacientes avaliando os efeitos da manobra de recrutamento alveolar na oxigena&#231;&#227;o e volume corrente exalado em pacientes com hipoxemia, no p&#243;s-operat&#243;rio imediato de cirurgia card&#237;aca, concluindo que, ap&#243;s a realiza&#231;&#227;o dessa t&#233;cnica, ocorreu aumento do &#237;ndice de oxigena&#231;&#227;o e da satura&#231;&#227;o perif&#233;rica de oxig&#234;nio, cooroborando os resultados deste estudo.</p>
        <p>Celebi et al.<xref ref-type="bibr" rid="B11">11</xref> randomizaram 60 pacientes p&#243;s-cirurgia de revasculariza&#231;&#227;o do mioc&#225;rdio, em tr&#234;s grupos de 20 pacientes: G1 (CPAP + manobra de recrutamento alveolar), G2 (PEEP-20 + manobra de recrutamento alveolar) e G3 (PEEP-5 + manobra de recrutamento alveolar). Conclu&#237;ram que as manobras aumentaram a oxigena&#231;&#227;o, diminu&#237;ram a atelectasia e que o G2 proporcionou melhor estabilidade hemodin&#226;mica. O que tamb&#233;m vai de encontro com os resultados apresentados neste estudo. A manobra de recrutamento alveolar &#233; de grande import&#226;ncia para a pr&#225;tica cl&#237;nica, pois melhora a oxigena&#231;&#227;o, facilita o desmame do paciente da ventila&#231;&#227;o mec&#226;nica, restaura o volume corrente e a capacidade ventilat&#243;ria e, por fim, &#233; efetivo na corre&#231;&#227;o de complica&#231;&#245;es pulmonares que s&#227;o observadas com freq&#252;&#234;ncia nesta fase de recupera&#231;&#227;o.<xref ref-type="bibr" rid="B24">24</xref><sup>,</sup><xref ref-type="bibr" rid="B25">25</xref>
				</p>
        <p>No presente estudo, a respira&#231;&#227;o por press&#227;o positiva intermitente tamb&#233;m contribuiu para a redu&#231;&#227;o do n&#237;vel de lactato arterial, melhora do &#237;ndice de oxigena&#231;&#227;o, press&#227;o parcial de oxig&#234;nio no sangue arterial e satura&#231;&#227;o de oxig&#234;nio. Estes resultados concordam com o estudo de Romanini et al.,<xref ref-type="bibr" rid="B26">26</xref> que realizaram um ensaio cl&#237;nico randomizado com 40 pacientes submetidos &#224; cirurgia de revasculariza&#231;&#227;o do mioc&#225;rdio, divididos em dois grupos, respira&#231;&#227;o por press&#227;o positiva intermitente e incentivador respirat&#243;rio, e conclu&#237;ram que a respira&#231;&#227;o por press&#227;o positiva intermitente foi mais eficiente, pois houve melhora na satura&#231;&#227;o perif&#233;rica de oxig&#234;nio e no &#237;ndice de oxigena&#231;&#227;o.</p>
        <p>Uma revis&#227;o sistem&#225;tica conduzida por Silveira et al.<xref ref-type="bibr" rid="B27">27</xref> verificou a efetividade da press&#227;o positiva (respira&#231;&#227;o por press&#227;o positiva intermitente, CPAP e BIPAP), e das t&#233;cnicas de fisioterapia convencional e incentivador respirat&#243;rio, na recupera&#231;&#227;o da fun&#231;&#227;o pulmonar, em pacientes no p&#243;s-operat&#243;rio de cirurgia card&#237;aca. Apesar dos benef&#237;cios observados, n&#227;o foi poss&#237;vel diferenciar o n&#237;vel de evid&#234;ncia entre as t&#233;cnicas, n&#227;o sendo poss&#237;vel identificar superioridade entre elas, pois nenhum estudo comparou de maneira simult&#226;nea as tr&#234;s modalidades de press&#227;o positiva.</p>
        <p>Ferreira et al.,<xref ref-type="bibr" rid="B28">28</xref> revisaram estudos entre 2006 e 2011, com o objetivo de verificar superioridade entre as modalidade de ventila&#231;&#227;o mec&#226;nica n&#227;o-invasiva - CPAP, BiPAP&#174;, respira&#231;&#227;o por press&#227;o positiva intermitente e PSV + PEEP. Apesar da escassez de estudos, a respira&#231;&#227;o por press&#227;o positiva intermitente mostrou superioridade na revers&#227;o da hipoxemia, e o BiPAP na melhora do n&#237;vel de oxigena&#231;&#227;o e das freq&#252;&#234;ncias respirat&#243;ria e card&#237;aca, em compara&#231;&#227;o &#224;s demais modalidades. Com o uso da t&#233;cnica de expans&#227;o pulmonar, pode-se observar aumento no n&#237;vel de oxigena&#231;&#227;o arterial, devido &#224; expans&#227;o dos pulm&#245;es e, consequentemente, na fun&#231;&#227;o pulmonar, bemcomo melhor elimina&#231;&#227;o de secre&#231;&#245;es e da permeabilidade das vias a&#233;reas, o que vai de encontro com a conclus&#227;o encontrada neste estudo.</p>
        <p>Os resultados devem ser observados com cautela devido a limita&#231;&#245;es na realiza&#231;&#227;o do presente estudo, tais como: a falta de estudos completos na literatura que pudessem ser usados para a compara&#231;&#227;o de resultados, por se tratar de um estudo de antes e depois, onde os pacientes s&#227;o controles de si mesmos. Al&#233;m disso, a aus&#234;ncia de grupo controle dificulta a comprova&#231;&#227;o dos resultados obtidos. Entretanto, os ganhos obtidos sinalizam a tend&#234;ncia dos beneficios observados.</p>
      </sec>
      <sec sec-type="conclusions">
        <title>Conclus&#227;o</title>
        <p>As t&#233;cnicas de terapia de expans&#227;o pulmonar produziram efeitos na redu&#231;&#227;o do n&#237;vel lactato arterial, melhora do &#237;ndice de oxigena&#231;&#227;o - de uma maneira indireta na press&#227;o parcial de oxig&#234;nio e na fra&#231;&#227;o inspirada de oxig&#234;nio - e na satura&#231;&#227;o perif&#233;rica de oxig&#234;nio dos pacientes na fase do p&#243;s-operat&#243;rio imediato de cirurgia card&#237;aca. Por&#233;m, novos estudos, de prefer&#234;ncia controlados, devem ser realizados para confirma&#231;&#227;o do presente resultado.</p>
      </sec>
    </body>
    <back>
      <fn-group>
        <fn fn-type="financial-disclosure">
          <p>
            <bold>Fontes de Financiamento</bold>
          </p>
          <p>O presente estudo n&#227;o teve fontes de financiamento externas.</p>
        </fn>
        <fn fn-type="other">
          <p>
            <bold>Vincula&#231;&#227;o Acad&#234;mica</bold>
          </p>
          <p>Este artigo &#233; parte da disserta&#231;&#227;o de mestrado de Silvana Souza Oliveira, Mansueto Neto e Roque Aras Junior pela Universidade Federal da Bahia - Faculdade de Medicina.</p>
        </fn>
        <fn fn-type="other">
          <p>
            <bold>Aprova&#231;&#227;o &#201;tica e consentimento informado</bold>
          </p>
          <p>Trabalhos experimentais envolvendo seres humanos: Este estudo foi aprovado pelo Comit&#234; de &#201;tica Hospital Ana Nery - UFBA/SESAB sob o n&#250;mero de protocolo 861.257. Todos os procedimentos envolvidos nesse estudo est&#227;o de acordo com a Declara&#231;&#227;o de Helsinki de 1975, atualizada em 2013. O consentimento informado foi obtido de todos os participantes inclu&#237;dos no estudo.</p>
        </fn>
      </fn-group>
    </back>
  </sub-article>
</article>
