Association between extreme weather events and postoperative adverse outcomes: a systematic review

Extreme weather events have been increasing in frequency and intensity globally. Surgical patients may be particularly susceptible to the impact of extreme weather on health outcomes and health care delivery. Our primary objective was to synthesize the available evidence on the association between extreme weather events and postoperative adverse outcomes within thirty days after surgery.

We performed a systematic review of the literature, searching MEDLINE on PubMed®, Embase, CINAHL, Web of Science, and the Cochrane Database of Systematic Reviews for English-language, full-text articles published prior to 30 May 2024. We included studies that involved surgical patients, exposure to an extreme weather event thirty days pre- or postoperatively, and had one or more adverse outcome within thirty days postoperatively. Screening and extraction were performed by two independent reviewers. We also performed thematic analysis to summarize the impact of extreme weather events on postoperative health care delivery.

Our search identified 8,422 articles, of which 4 studies encompassing 117,804 surgical patients qualified for inclusion (3 on heatwave or extreme heat, and 1 on wildfire smoke). Retrospective studies linked temperatures > 40 °C to increased perioperative complications in trauma patients (1 study), temperatures > 30 °C to increased length of hospital stay in patients older than 60 yr (1 study), and wildfire smoke to respiratory complications in pediatric patients with prematurity or respiratory conditions (1 study). Health delivery domains that were affected were patients (3 studies), care processes and infrastructure (2 studies), and capacity (2 studies). The studies were limited by heterogenous definitions of exposure, confounding, and bias.

Our review revealed major research gaps in the impact of extreme weather events on postoperative outcomes and health care delivery. Existing literature is scant and limited by substantial methodologic issues, and further research is urgently required.

PROSPERO ( CRD42023435273 ); first submitted 26 June 2023.