Low hemoglobin concentration is associated with poor outcome after peripheral arterial surgery

Abstract

Objective: To assess the influence of low hemoglobin (Hb) concentration on major adverse cardiac events (MACE) and mortality in patients undergoing peripheral arterial surgery.

Methods: This was a retrospective cohort study of patients undergoing peripheral arterial reconstructive surgery at a tertiary vascular center. Preoperative factors linked with the occurrence of MACE and death on univariate analysis (P ≤ .1) were included in a multivariate model to confirm the independent association with the outcome variables.

Results: A total of 360 consecutive patients (238 men) with a mean (standard deviation) age of 69 (10.7) years and Hb of 13.0 (2.12) g/dL treated under the care of a single specialist between January 2004 and December 2011 were included in the analysis. Of these, 193 (53.6%) were anemic. In all, 26 (7%) had a postoperative MACE and 18 (5%) died. On multivariate analysis, age > 80 years (odds ratio [OR] = 3; 95% confidence interval [CI] [1.2-7.5]; P = .025), renal impairment (OR = 3.2; 95% CI [.99-10.2]; P = .053), coronary disease (OR = 3.6; 95% CI [1.5-8.7]; P = .005), and low Hb (OR for each 1 g/dL drop below the mean = 1.4 [1.13-1.7]; P = .002) were independent risk factors for MACE. Unplanned surgery (OR = 4.5; 95% CI [1.2-16.9]; P = .025) and low Hb (OR for each 1 g/dL drop below the mean = 1.5; 95% CI [1.14-1.86]; P = .002) were independent risk factors for death.

Conclusion: In peripheral arterial surgery, preoperative low Hb is associated with MACE and death. Further investigation is necessary to elucidate whether this relationship is causal. Meanwhile, consideration should be given to treating preoperative anemia as a significant risk factor for adverse outcome in this setting.

Keywords: anemia; peripheral arterial disease; peripheral arterial surgery.