Predictors of in-hospital mortality following noncardiac surgery: Findings from an analysis of a South African hospital administrative database

Abstract

Background. Predictors of in-hospital mortality (IHM) following non-cardiac surgery in South African (SA) patients are not well described. Objective. To determine the association between patient comorbidity and IHM in a cohort of SA non-cardiac surgery patients. Methods. Data related to comorbidity and IHM for 3 727 patients aged ≥45 years were obtained from a large administrative database at a tertiary SA hospital. Logistic regression analysis was used to determine independent predictors of IHM. In addition, population-attributable fractions (PAFs) were calculated for all clinical factors identified as independent predictors of IHM. Results. Renal dysfunction, congestive heart failure, cerebrovascular disease, male gender and high-risk surgical specialties were independently associated with IHM (odds ratios (95% confidence intervals) 7.585 (5.480 - 10.50); 2.604 (1.119 - 6.060); 2.645 (1.414 - 4.950); 1.433 (1.107 - 1.853); and 1.646 (1.213 - 2.233), respectively). Ischaemic heart disease, diabetes and hypertension were not identified as independent predictors of IHM in SA non-cardiac surgery patients. Renal dysfunction had the largest contribution to IHM in this study (PAF 0.34), followed by high-risk surgical specialties (PAF 0.15), male gender (PAF 0.08), cerebrovascular disease (PAF 0.03) and congestive heart failure (PAF 0.03). Conclusion. Renal dysfunction, congestive heart failure, cerebrovascular disease, male gender and high-risk surgical specialties were major contributors to increased IHM in SA non-cardiac surgery patients. Prospectively designed research is required to determine whether ischaemic heart disease, diabetes and hypertension contribute to IHM in these patients.