Strategies to reduce postoperative pulmonary complications after noncardiothoracic surgery: systematic review for the American College of Physicians.
BACKGROUND
Postoperative pulmonary complications are as frequent and clinically important as cardiac complications in terms of morbidity, mortality, and length of stay. However, there has been much less research and no previous systematic reviews of the evidence of interventions to prevent pulmonary complications.


OBJECTIVE
To systematically review the literature on interventions to prevent postoperative pulmonary complications after noncardiothoracic surgery.


METHODS
MEDLINE English-language literature search, 1 January 1980 through 30 June 2005, plus bibliographies of retrieved publications.


METHODS
Randomized, controlled trials (RCTs); systematic reviews; or meta-analyses that met predefined inclusion criteria.


METHODS
Using standardized forms, the authors abstracted data on study methods, quality, intervention and control groups, patient characteristics, surgery, postoperative pulmonary complications, and adverse events.


RESULTS
The authors qualitatively synthesized, without meta-analysis, evidence from eligible studies. Good evidence (2 systematic reviews, 5 additional RCTs) indicates that lung expansion interventions (for example, incentive spirometry, deep breathing exercises, and continuous positive airway pressure) reduce pulmonary risk. Fair evidence suggests that selective, rather than routine, use of nasogastric tubes after abdominal surgery (2 meta-analyses) and short-acting rather than long-acting intraoperative neuromuscular blocking agents (1 RCT) reduce risk. The evidence is conflicting or insufficient for preoperative smoking cessation (1 RCT), epidural anesthesia (2 meta-analyses), epidural analgesia (6 RCTs, 1 meta-analysis), and laparoscopic (vs. open) operations (1 systematic review, 1 meta-analysis, 2 additional RCTs), although laparoscopic operations reduce pain and pulmonary compromise as measured by spirometry. While malnutrition is associated with increased pulmonary risk, routine total enteral or parenteral nutrition does not reduce risk (1 meta-analysis, 3 additional RCTs). Enteral formulations designed to improve immune status (immunonutrition) may prevent postoperative pneumonia (1 meta-analysis, 1 additional RCT).


CONCLUSIONS
The overall quality of the literature was fair: Ten of 20 RCTs and 6 of 11 systematic reviews were good quality.


CONCLUSIONS
Few interventions have been shown to clearly or possibly reduce postoperative pulmonary complications.
Lawrence
Valerie A
VA
South Texas Veterans Health Care System and Medicine/General Medicine, The University of Texas Health Science Center at San Antonio, San Antonio, Texas 78229-3900, USA. vlawrence@uthscsa.edu
Cornell
John E
JE
Smetana
Gerald W
GW
D000698:Analgesia / Q000379:methods; D000758:Anesthesia / Q000379:methods; D019411:Clinical Laboratory Techniques; D006801:Humans; D010535:Laparoscopy; D008171:Lung Diseases / Q000209:etiology / Q000517:prevention & control*; D011182:Postoperative Care / Q000379:methods; D011183:Postoperative Complications / Q000517:prevention & control*; D011300:Preoperative Care / Q000379:methods; D012131:Respiratory Insufficiency / Q000209:etiology / Q000517:prevention & control*; D018570:Risk Assessment; D012307:Risk Factors; D013514:Surgical Procedures, Operative