NORMAL SERUM CONCENTRATIONS OF S-100 PROTEIN AND CHANGES IN CEREBROSPINAL-FLUID CONCENTRATIONS OF S-100 PROTEIN DURING AND AFTER THORACOABDOMINAL AORTIC-ANEURYSM SURGERY - IS S-100 PROTEIN-A BIOCHEMICAL MARKEROF CLINICAL-VALUE IN DETECTING SPINAL-CORD ISCHEMIA

Purpose: This study was performed to determine the concentration of S- 100 protein in serum and in the cerebrospinal fluid (CSF) during and 2 4 hours after thoracoabdominal aortic aneurysm repair. Methods: This p rospective study was performed at St. Antonius Hospital in Nieuwegein, The Netherlands. Eight patients who underwent elective thoracoabdomin al aortic surgery participated in the study. Arterial blood and CSF sa mples for analysis of S-100 protein were drawn after induction of anes thesia, during the cross-clamp period of the critical segment, after 5 minutes of reperfusion, during the closure of the skin, and 24 hours after closure of the skin. Results: No increase in S-100 protein conce ntration could be detected in serum (<0.2 mu g/L). The S-100 protein c oncentration in CSF increased during the procedure in all patients (4. 2 +/- 3.1 mu g/L). However, in one patient, who became paraplegic, the S-100 protein concentration in CSF increased even further after 24 ho urs (10 mu g/L). Conclusions: The preliminary results suggest that S-1 00 protein in CSF may be a marker of clinical value in evaluating the effects of measures to detect and reduce spinal cord ischemia.