Impact of haemoglobin concentration on cardiovascular outcome after vascular surgery: a retrospective observational cohort study.

Background: Although low preoperative haemoglobin (Hb) concentration is a well known risk factor for adverse outcome, little is known about decreases in Hb and postoperative Hb concentrations.

Objectives: The aim of this study was to evaluate the prognostic impact of both pre- and postoperative Hb concentrations (divided into low, intermediate and high tertiles) as well as Hb decrease, defined as preoperative minus postoperative Hb (g dl(-1)), on postoperative cardiovascular events in vascular surgery patients.

Design: A retrospective observational cohort study.