QUESTIONS: Among patients having elective abdominal surgery, how much does preoperative physiotherapy education with breathing exercise training reduce the incidence of postoperative pulmonary complications (PPCs), hospital length of stay and 12-month mortality? How stable are the treatment effects across different PPC definitions, including pneumonia? How much do the treatment effects on PPC, hospital length of stay and mortality vary within clinically relevant subgroups?

DESIGN: Individual participant-level meta-analysis (n = 800) from two randomised controlled trials analysed with multivariable regression.

PARTICIPANTS: Adults undergoing major elective abdominal surgery.

INTERVENTIONS: Experimental participants received a single preoperative session with a physiotherapist within 4 weeks of surgery and educated on PPC prevention with breathing exercises and early mobilisation. They were taught breathing exercises and instructed to start them immediately on waking from surgery. The control group received no preoperative or postoperative physiotherapy, or early ambulation alone.

OUTCOME MEASURES: PPC, hospital length of stay and 12-month mortality.

RESULTS: Participants who received preoperative physiotherapy had 47% lower odds of developing a PPC (adjusted OR 0.53, 95% CI 0.34 to 0.85). This effect was stable regardless of PPC definition. Effects were greatest in participants who smoked, were aged ≤ 45 years, had abnormal body weight, had multiple comorbidities, or were undergoing bariatric or upper gastrointestinal surgery. Participants having operations ≤ 3 hours in duration were least responsive to preoperative physiotherapy. Participants with multiple comorbidities were more likely to have a shorter hospital stay if provided with preoperative physiotherapy (adjusted MD -3.2 days, 95% CI -6.2 to -0.3). Effects on mortality were uncertain.

CONCLUSION: There is strong evidence to support preoperative physiotherapy in preventing PPCs after elective abdominal surgery.