Neurologic complications in cardiac surgery: can risk scores be applied?

Introduction

Neurologic complications (NC) in cardiac surgery are not rare (5–15%). Their etiopathogeny is multifactorial, and the risk factors are numerous. Neurologic complications result in high morbidity and mortality rates, and high hospital costs. Most risk scores assess mortality, and the risk for stroke assessed by the AHA/ACC score refers only to patients with coronary disease. One may thus question whether risk scores for NC can be applied in a general population.

Objective

To assess the risk scores of patients with NC undergoing cardiac surgery.

Methods

A retrospective observational study including information about 1431 patients from a databank, of whom 45 (3.1%) had reversible or permanent neurologic deficit. The sample was divided into two groups: Group 1 (G1), patients with NC; and Group 2 (G2), the historic control. The Cleveland score, Euroscore, and AHA/ACC score for stroke were assessed, as was the occurrence of death. The Student t test was used for analyzing the means of continuous variables.

Results

G1 comprised 24 men (53.3%), and the mean age of patients was 63.5 (SD 13.6) years. The surgeries were as follows: 26 myocardial revascularizations (57.7%), 12 valvular replacements (26.6%), one combined (2.2%), two congenital (4.4%), and three aortic surgeries (6.6%). The means of the Cleveland score, Euroscore, and AHA/ACC score were: in G1: 4.5 (SD 3.3), 6.1 (SD 4.2), and 4.1 (SD 2.6), respectively; and in G2: 2.9 (SD 2.6), 3.6 (SD 2.8), and 2.5 (SD 2.5), respectively, with statistical significance (P < 0.0001, P < 0.0001, and P < 0.0001). The mortality rate was 24.4% in G1 and 9.2% in G2 (P = 0.002).

Conclusion

The risk scores for cardiac surgery applied for mortality reflected a greater incidence of neurologic complications in this population.