Modeling serum biomarkers S100 beta and neuron-specific enolase as predictors of outcome after out-of-hospital cardiac arrest: an aid to clinical decision making.
OBJECTIVE
The aim of this study was to determine the added value of the serum biomarkers S100 and neuron-specific enolase to clinical characteristics for predicting outcome after out-of-hospital cardiac arrest.


BACKGROUND
Serum S100 beta (S100B) and neuron-specific enolase concentrations rise after brain injury.


METHODS
A prolective observational study was conducted among all adult survivors of nontraumatic out-of-hospital cardiac arrest admitted to 1 hospital (April 3, 2008 to April 3, 2011). Three blood samples (on arrival and on days 1 and 3) were drawn for biomarkers, contingent on survival. Follow-up continued until in-hospital death or discharge. Outcomes were defined as good (Cerebral Performance Category score 1 or 2) or poor (Cerebral performance category score 3 to 5).


RESULTS
A total of 195 patients were included (65.6% men, mean age 73 ± 16 years), with presenting rhythms of asystole in 61.5% and ventricular tachycardia or ventricular fibrillation in 24.1%. Only 43 patients (22.0%) survived to hospital discharge, 26 (13.3%) with good outcomes. Patients with good outcomes had significantly lower S100B levels at all time points and lower neuron-specific enolase levels on days 1 and 3 compared with those with poor outcomes. Independent predictors at admission of a good outcome were younger age, a presenting rhythm of ventricular tachycardia or ventricular fibrillation, and lower S100B level. Predictors on day 3 were younger age and lower day 3 S100B level. The area under the receiver-operating characteristic curve of the admission-day model was 0.932 with and 0.880 without biomarker data (p = 0.027 for the difference).


CONCLUSIONS
Risk stratification after out-of-hospital cardiac arrest using both clinical and biomarker data is feasible. The biomarkers, although adding an ostensibly modest 5.2% to the area under the receiver-operating characteristic curve, substantially reduced the level of uncertainty in decision making. Nevertheless, current biomarkers cannot replace societal considerations in determining acceptable levels of uncertainty. (Protein S100 Beta as a Predictor of Resuscitation Outcome; NCT00814814).
Shaare Zedek Medical Center, Jerusalem, Israel. einav_s@szmc.org.il
Sharon
S
Einav
Nechama
N
Kaufman
Nurit
N
Algur
Jeremy D
JD
Kark
D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D001925:Brain Damage, Chronic / Q000097:blood / Q000401:mortality; D003661:Decision Support Techniques; D005260:Female; D006801:Humans; D007557:Israel; D008297:Male; D008875:Middle Aged; D015999:Multivariate Analysis; D009414:Nerve Growth Factors / Q000097:blood*; D058687:Out-of-Hospital Cardiac Arrest / Q000097:blood* / Q000401:mortality; D010751:Phosphopyruvate Hydratase / Q000097:blood*; D011237:Predictive Value of Tests; D011379:Prognosis; D011446:Prospective Studies; D012372:ROC Curve; D012151:Resuscitation; D064568:S100 Calcium Binding Protein beta Subunit; D009418:S100 Proteins / Q000097:blood*
D009414:Nerve Growth Factors; D064568:S100 Calcium Binding Protein beta Subunit; D009418:S100 Proteins; C579160:S100B protein, human; D010751:Phosphopyruvate Hydratase