The use of incentive spirometry for preventing pulmonary complications in adults people undergoing coronary artery bypass graft surgery

Breathing complications after coronary artery bypass graft (CABG) surgery increases hospital stay and is with associated high healthcare costs. CABG may interfere with the lungs, causing sections of them to collapse which may lead to pneumonia. Re-inflating areas of the collapsed lung may be done by a device - an incentive spirometer - that reinforces a pattern of breathing which prevents and reverses the process. This device is used alone or in combination with other physiotherapy techniques.

This update included 592 participants from seven studies (two new and one that had been excluded in the previous 2007 review). We found evidence from four small trials that incentive spirometry offers no advantage over standard post-surgical physical therapy, or preoperative education in preventing breathing complications and pneumonia, improving lung function, or shortening length of hospital stay in patients undergoing CABG. Bigger and better designed trials are needed to determine if there is any role for incentive spirometry.

Authors' conclusions: 

Our update review suggests there is no evidence of benefit from IS in reducing pulmonary complications and in decreasing the negative effects on pulmonary function in patients undergoing CABG. In view of the modest number of patients studied, methodological shortcomings and poor reporting of the included trials, these results should still be interpreted cautiously. An appropriately powered trial of high methodological rigour is needed to determine if there are patients who may derive benefit from IS following CABG.

Read the full abstract...

Incentive spirometry (IS) is a treatment technique that uses a mechanical device to reduce pulmonary complications during postoperative care. This is an update of a Cochrane review first published in 2007.


Update the previously published systematic review to compare the effects of IS for preventing postoperative pulmonary complications in adults undergoing coronary artery bypass graft (CABG).

Search strategy: 

We searched CENTRAL and DARE on The Cochrane Library (Issue 2 of 4 2011), MEDLINE OVID (1948 to May 2011), EMBASE (1980 to Week 20 2011), LILACS (1982 to July 2011) , the Physiotherapy Evidence Database (PEDro) (1980 to July 2011), Allied & Complementary Medicine (AMED) (1985 to May 2011), CINAHL (1982 to May 2011).

Selection criteria: 

Randomised controlled trials comparing IS with any type of prophylactic physiotherapy for prevention of postoperative pulmonary complications in adults undergoing CABG.

Data collection and analysis: 

Two reviewers independently evaluated trial quality using the guidelines of the Cochrane Handbook for Systematic Reviews and extracted data from included trials. For continuous outcomes, we used the generic inverse variance method for meta-analysis and for dichotomous data we used the Peto Odds Ratio.

Main results: 

This update included 592 participants from seven studies (two new and one that had been excluded in the previous review in 2007. There was no evidence of a difference between groups in the incidence of any pulmonary complications and functional capacity between treatment with IS and treatment with physical therapy, positive pressure breathing techniques (including continuous positive airway pressure (CPAP), bilevel positive airway pressure (BiPAP) and intermittent positive pressure breathing (IPPB), active cycle of breathing techniques (ACBT) or preoperative patient education. Patients treated with IS had worse pulmonary function and arterial oxygenation compared with positive pressure breathing. Based on these studies there was no improvement in the muscle strength between groups who received IS demonstrated by maximal inspiratory pressure and maximal expiratory pressure.