NSE and S-100B are not sufficiently predictive of neurologic outcome after therapeutic hypothermia for cardiac arrest

Introduction

Prognostication of cardiac arrest survivors is challenging since therapeutic hypothermia (TH) has been introduced. We evaluated serum biomarkers and motor response.

Methods

This was a retrospective data analysis including patients in the years 2007–2012. Blood was drawn and a neurological examination was performed on admission and every morning. Outcomes were evaluated 6 months after discharge and dichotomized into good (cerebral performance category (CPC) = 1 or 2) and poor (CPC = 3, 4 or 5).

Results

123 patients (79.7% male, 63 ± 14 years) received TH; 50% had a good outcome. On admission, S-100B (P = 0.004) was significantly associated with the outcome, as well as neuron-specific enolase (NSE; P = 0.020) and S-100B (P = 0.004) on day 1 after admission. NSE on day 2, NSE progression from day 1 to 2 and motor response on day 3 also predicted the outcome (all P < 0.001).NSE > 33 μg l⁻¹ only predicted a poor outcome with a specificity of 76%. An absent motor response on day 3 was the most sensitive marker (94%). NSE > 41.1 μg l⁻¹ combined with S-100B > 0.461 μg l⁻¹ on day 1 was the most specific marker (96%).

Conclusion

Although NSE and S-100B levels are associated with the outcome, the use of previously described cut-off values was insufficiently predictive of neurologic outcome. Caution should be exercised in the use of these tests to provide neuroprognostication.