Influence of Perioperative Serum Magnesium for Cardiac and Noncardiac Morbidity and Mortality Following Emergency Peripheral Vascular Surgery

Abstract

Objectives: To examine the influence of serum magnesium on 30-day mortality and cardiac and noncardiac morbidity.

Design: Retrospective cross-sectional observational study of routinely collected prospective data.

Setting: Single-center tertiary vascular center in the United Kingdom.

Participants: All patients undergoing arterial peripheral vascular surgery during an unplanned admission.

Interventions: Observational, no interventions implemented.

Measurements and main results: In the study, n = 197. One hundred thirty-eight were male (70.1%). Median age at procedure was 70.0 years (interquartile range 20.0). Of those with a documented history, 37.9% had diabetes, 81.7% had a smoking history, 63.7% had hypertension, and 26.5% had known ischemic heart disease or heart failure. There was a significant perioperative change in magnesium (p < 0.001), calcium (p < 0.001), and creatinine (p = 0.004), with no significant alteration in potassium (p = 0.096). Thirty-day mortality was 4.6%. Thirty-day cardiac morbidity was 4.1%. Thirty-day noncardiac morbidity was 32.3%. Postoperative magnesium was independently predictive for 30-day mortality (p = 0.02, odds ratio [OR] 0.96, 95% confidence interval [CI] 0.94-0.99) and cardiac morbidity (p = 0.03, OR 0.97, 95% CI 0.95-1.00). Only a previous smoking history was independently predictive of noncardiac morbidity (p = 0.03, OR 9.67, 95% CI 1.20-78.15).

Conclusion: Perioperative changes in serum magnesium may have an influence on short-term mortality and cardiac complications. This should be considered in the management of patients undergoing unplanned peripheral vascular surgery; however, further research is needed to examine the benefit of supplementation perioperatively and to explore the exact mechanisms.

Keywords: emergencies; magnesium; morbidity; mortality; peripheral arterial disease.