24). To that end, the 6S hierarchy of evidence suggests searches would begin at the systems level (DiCenso et al., 2009, p. 99); but, as a student, this level of evidence is inaccessible. Accordingly, the search commenced at the summaries level and progressed down the hierarchy of evidence toward the studies level until appropriate evidence was obtained. To accomplish this, the following search engines and databases were used: TRIP database, MacPLUS Federated Search, PubMed, Google Scholar, Health Evidence, ACP Journal Club, Evidence Based Nursing, and National Guideline Clearinghouse. The terms used to yield the results included: incentive spirometry, spirometer, coronary artery bypass graft, CABG, postoperative, complications, prevention, pulmonary, deep breathing exercises, coughing, deep inspiration, cardiac surgery, atelectasis, and …show more content…
This article sought a clear objective, which was “to review and compare the role of IS in preventing postoperative pulmonary complications in adults undergoing CABG” (Freitas et al., 2012, p. 3). The authors performed a thorough and comprehensive search which yielded seven articles for final inclusion, all of which were randomised controlled trials (RCT). Next, the authors completed a meta-analysis of the appropriate studies for three outcomes and a narrative analysis for the remaining outcomes. Two of the review outcomes are directly related to the clinical question. Specifically, five of the seven studies investigated atelectasis as an outcome, but due to comparison variability only two studies were statistically analysed. These studies were found to be homogeneous using a chi-square test yielding a p-value of 0.66. Interestingly, the treatment effect between IS and conventional physical therapy (CPT) in the prevention of atelectasis was absent of statistical significance. In particular, the p-value was 0.75, odds ratio 1.11, and the confidence interval (CI) was 0.58, 2.16 for a dichotomous outcome, thus suggesting that IS increases the odds of atelectasis by 11 percent. Next, pneumonia was analysed and four studies reported this outcome. However, due to variability, only two were combined for