Changes in S-100 protein serum levels in survivors of out-of-hospital cardiac arrest treated with mild therapeutic hypothermia: a prospective, observational study.
BACKGROUND
Knowledge about the influence of current neuroprotective interventions on prognostic markers after survival from cardiac arrest is lacking. This study aimed to investigate the effects of mild therapeutic hypothermia on the release of the astroglial protein S-100 after cardiopulmonary resuscitation (CPR) in survivors of out-of-hospital cardiac arrest.


METHODS
This was a prospective, observational study performed during a two-year period, involving medical emergency services and five collaborating hospitals at the city of Aachen, Germany. Sixty-eight subjects were enrolled by the emergency physician on duty by taking blood samples after successful attempts at resuscitation with return of spontaneous circulation (ROSC), followed by samples at 6, 12, 24, 72 and 120 hours post ROSC by the appropriate intensive care unit staff. Depending on the decision of the attending physician, subjects were cooled down to 33 degrees C (n = 37) for 24 hours or were held at 37 degrees C (n = 31). Patients were tracked for estimating mortality and gross neurological outcome for 14 days.


RESULTS
S-100 levels in patients not receiving mild therapeutic hypothermia (normothermia (NT)) showed equivalent numbers as compared with cooled patients (mild therapeutic hypothermia (MTH)) on baseline (NT = 1.38 mug/l versus MTH = 1.30 microg/l; P = 0.886). S-100 levels on baseline were significantly lower in patients with a good neurological outcome at 14 days after the event in comparison to their peers with adverse outcome (P = 0.014). Although the difference in S-100 levels of MTH patients with adverse or favourable neurological outcome reached statistical significance, it did not in NT patients.


CONCLUSIONS
Although the predictive power of S-100 levels were best on admission but not at later time points, MTH had no influence on S-100 serum levels in survivors of non-traumatic out-of-hospital cardiac arrest in the particular setting of this investigation.
Department of Anaesthesiology, University Hospital RWTH Aachen, Pauwelsstrasse 30, 52074 Aachen, Germany. mderwall@ukaachen.de
Matthias
M
Derwall
Christian
C
Stoppe
David
D
Brücken
Rolf
R
Rossaint
Michael
M
Fries
D000368:Aged; D016887:Cardiopulmonary Resuscitation; D004632:Emergency Medical Services / Q000379:methods*; D005260:Female; D005858:Germany; D006323:Heart Arrest / Q000097:blood* / Q000503:physiopathology / Q000628:therapy; D006801:Humans; D007036:Hypothermia, Induced; D008297:Male; D008875:Middle Aged; D019370:Observation; D011446:Prospective Studies; D009418:S100 Proteins / Q000097:blood*; D017741:Survivors
D009418:S100 Proteins