Postoperative pulmonary complications in adult surgical patients in low- and middle-income countries: a systematic review and meta-analysis

Abstract

Background: After surgery, patients are at risk of developing postoperative pulmonary complications (PPCs). Our current understanding of PPCs is based on data from high-income countries.

Methods: A systematic review and meta-analysis was conducted to evaluate the incidence of PPCs in adult postsurgical patients from low- and middle-income countries (LMICs). The protocol was registered in PROSPERO (CRD42020212932). The search strategy was performed in 2021 on several electronic databases. Studies were assessed for risk of bias with the modified Newcastle-Ottawa Scale. Forest plots of the event rate for the incidence of PPCs and factors associated with PPCs were created.

Results: The search strategy identified 1 052 records. Fifteen studies were included in the final review (total of 4 873 participants). Five studies were of high methodological quality. The overall pooled event rate for the incidence of PPCs was 22.4% (95% confidence interval (CI), 15.76–30.78%). In-hospital mortality in patients who developed PPCs was 33.1%. PPCs were identified as a risk factor for in-hospital mortality (odds ratio (OR) 18.2, CI 11.01–30.09). Insufficient outcome data were available to determine the association of PPCs between elective versus emergency surgery, and cardiothoracic versus non-cardiothoracic surgery. Advanced age was associated with the development of PPCs (MD 4.7, 95% CI 0.63–8.7). Male sex was associated with the development of PPCs (OR 1.5, 95% CI 1.17–2.02). PPCs were associated with increased length of hospital stay (mean difference (MD) 6.5, 95% CI 4.04–8.96).

Conclusions: The incidence of PPCs was 22.4% following surgery in adult patients in LMICs and was influenced by differences in the definitions of PPCs used. PPCs were identified as a risk factor for in-hospital mortality. Data on the type of surgery and patient characteristics were poorly reported. Further research on PPCs in LMICs is needed to provide granular data for future use.