Impact of Lung Expansion Therapy Using Positive End-Expiratory Pressure in Mechanically Ventilated Patients Submitted to Coronary Artery Bypass Grafting

Abstract

ObjectiveTo evaluate the impact of different levels of positive end-expiratory pressure (PEEP) on gas exchange in patients undergoing coronary artery bypass grafting (CABG).MethodsA randomized clinical trial was conducted with patients undergoing CABG surgery. Patients were randomized into three groups: Group 10, PEEP of 10 cmH2O; Group 12, PEEP of 12 cmH2O; and Group 15, PEEP of 15 cmH2O. After the randomization, all patients underwent gas analysis at three moments: (1) before lung expansion therapy (LET); (2) 30 minutes after LET; and (3) one hour after extubation.ResultsSixty-six patients were studied, of which 61.7% were men, with mean age of 64 ± 8.9 years. Patients allocated to Group 15 showed a significant improvement in gas exchange comparing pre- and post-expansion values (239±21 vs. 301±19, P<0,001) and the increase was maintained after extubation (278±26). Despite the use of high levels of PEEP, no significant hemodynamic change was evidenced.ConclusionIt is concluded that high levels of PEEP (15 cmH2O) are beneficial for the improvement of gas exchange in patients undergoing CABG.

Optimal Positive End Expiratory Pressure Levels in Ventilated Patients Without Acute Respiratory Distress Syndrome: A Bayesian Network Meta-Analysis and Systematic Review of Randomized Controlled Trials

“…Meanwhile, the year of publication widely varied across the studies, with 12 of them published before 2000 ( Table 1 ). RoB was high in 18 ( 15 – 17 , 20 , 23 , 24 , 27 , 28 , 30 – 32 , 34 – 38 , 40 , 41 ) and low in 10 ( 5 , 10 , 18 , 19 , 21 , 22 , 25 , 26 , 29 , 33 ) trials. The high RoB was attributed to blinding of participants, personnel and outcome assessors ( Figure 3 ).…”

“…A total of 11 eligible articles(5,10,16,19,21, 23,25,29,33,35,38), with 1,848 participants, reported duration of mechanical ventilation. Among them, 6 studies(16,19,21, 23,25,29), with 572 patients(16,19,21, 23,25,29). A summary of the RoBs is shown in Figure3while the resulting funnel plot is illustrated inFigure 4. among different PEEP strategies (higher vs. intermediate: MD: 0.02, 95% CI: −0.034, 0.073; intermediate vs. lower: MD: −0.03, 95% CI: −0.078, 0.017; and lower PEEP vs. ZEEP: MD: 0.03, 95% CI: 0.015, 0.046) (Figure 5A).…”

Higher PEEP versus Lower PEEP Strategies for Patients in ICU without Acute Respiratory Distress Syndrome: A Systematic Review and Meta-Analysis

“…After carefully reading the full text of the remaining 63 articles, we found 39 of them inappropriate for the following reasons: 1) not ICU patients (n = 3); 2) disequilibrium of other ventilation parameters (n = 7); 3) not RCT (n = 3); 4) animal trials (n = 2); 5) receiving different PEEP within single patients (n = 15); 6) including patients with ARDS or age under 18 (n = 2); 7) retrospective studies (n = 4); 8) intraoperative studies (n = 2) and 9) full article unavailable. Therefore, we nally analyzed 24 studies [5,8,[10][11][12][13][14][19][20][21][22][23][24][25][26][27][28][29][30][31][32][33][34][35] .…”

“…Although there was one meta-analysis published in 2016 investigating the possible effect of high PEEP, the quality of evidence was low and insu cient [15] . In our present meta-analysis, we added four recent RCTs [33][34][35] including one largest RCT concerning high PEEP usage in non-ARDS patients [14] . Moreover, given that most of the selected patients underwent operations, especially cardiac ones, we also assessed the impact of high PEEP on postoperative chest-tube drainage and RBC usage, with no signi cant difference found.…”

Current developments and future directions in respiratory physiotherapy

“…Positive end-expiratory pressure has been conducted in a study with mechanically ventilated patients submitted to coronary artery bypass grafting. It has been demonstrated that high levels of positive end-expiratory pressure (15 cmH 2 O) are beneficial for the improvement of gas exchange in those patients [62]. This technique has also been evaluated in patients after upper abdominal surgery, and no significant differences in lung expansion or post-operative pulmonary complications were observed compared with incentive spirometry [63].…”