Determination of perioperative neurologic complications in cardiac surgery by S100B and neuron-specific enolase

Introduction

There is still no appropriate method to reliably determine neurologic complications induced by extra-corporeal circulation (ECC). S100B and neuron-specific enolase (NSE) could be used as potential markers for a perioperative neurologic dysfunction.

Objective

To evaluate changes in S100B and NSE levels in patients after ECC and the correlation between preoperative and postoperative neurologic status

Patients and methods

Thirty consecutive patients (26 male/four female, median age 63.3 ± 9.9 years, range 44-82 years) underwent coronary artery bypass grafting. The neurologic status was examined 1day preoperative and 1-2 days after the ICU. Exclusion criteriawere as follows: neurologic disorders, liver and/or kidney dysfunction, history of a neoplasm or drug and/or alcohol abuse. Blood samples were collected at the following times: before anesthesia; at the end of ECC; and 6, 24 and 48 h postoperatively. Immunoluminometric assays [LIA-mat Sangtec (S100 and NSE)] were used to detect serum marker levels.

Results

S100B and NSE were normal before ECC in 29 patients. In one, S100B was preoperatively high without abnormal neurologic status before and after surgery. S100B showed a peak at the end of ECC (mean 3.56 μ g/l), and mean NSE 6h after the operation (mean 28.25 μ g/l). Nineteen patients (63.4%) had still high S100B 48 h after surgery (0.42 μ g/l). In 14 patients(46.6%), NSE was high (22.4 μ g/l) during first 48h. Two patients (6.6%) with elevated markers showed neurologic symptoms: focal seizure and psychosis (n = 1), hemiplegia (n = 1).

Conclusion

There are remarkable changes in S100B and NSE during operations with ECC. Even minor neurologic abnormalities after cardiac surgery can be detected by LIA. Neurologic disorders lead to elevated serum marker levels. Patients with elevated markers must not have clinically relevant neurologic symptoms.