Preoperative anaemia is associated with poor clinical outcome in non-cardiac surgery patients

Abstract

Background: Retrospective studies suggest that preoperative anaemia is associated with poor outcomes after surgery. The objective of this study was to describe mortality rates and patterns of intensive care resource use for patients with anaemia undergoing non-cardiac and non-neurological in-patient surgery.

Methods: We performed a secondary analysis of a large prospective study describing perioperative care and survival in 28 European nations. Patients at least 16 yr old undergoing in-patient surgery during a 7 day period were included in the study. Data were collected for in-hospital mortality, duration of hospital stay, admission to intensive care, and intensive care resource use. Multivariable logistic regression analysis was performed to understand the effects of preoperative haemoglobin (Hb) levels on in-hospital mortality.

Results: We included 39 309 patients in the analysis. Preoperative anaemia had a high prevalence in both men and women (31.1% and 26.5%, respectively). Multivariate analysis showed that patients with severe [odds ratio 2.82 (95% confidence interval 2.06-3.85)] or moderate [1.99 (1.67-2.37)] anaemia had higher in-hospital mortality than those with normal preoperative Hb concentrations. Furthermore, hospital length of stay (P<0.001) and postoperative admission to intensive care (P<0.001) were greater in patients with anaemia than in those with normal Hb concentrations.

Conclusions: Anaemia is common among non-cardiac and non-neurological surgical patients, and is associated with poor clinical outcome and increased healthcare resource use.

Clinical trial registration: NCT01203605 (ClinicalTrials.gov).

Keywords: anaemia; assessment, outcome; care, intensive; epidemiologic studies, cohort studies; mortality determinants.