Time-dependency of sensory evoked potentials in comatose cardiac arrest survivors.
OBJECTIVE
To assess the validity of early sensory evoked potential (SEP) recording for reliable outcome prediction in comatose cardiac arrest survivors within 48 h after restoration of spontaneous circulation (ROSC).


METHODS
Prospective cohort study in a medical intensive care unit of a university hospital.


METHODS
Twenty-five comatose, mechanically ventilated patients following cardiopulmonary resuscitation


RESULTS
Median nerve short- and long-latency SEP were recorded 4, 12, 24, and 48 h after ROSC. Cortical N20 peak latency and cervicomedullary conduction time decreased (improved) significantly between 4, 12, and 24 h after resuscitation in 22 of the enrolled patients. There was no further change in short-latency SEP at 48 h. The cortical N70 peak was initially detectable in seven patients. The number of patients with increased N70 peak increased to 11 at 12 h and 14 at 24 h; there was no further change at 48 h. Specificity of the N70 peak latency (critical cutoff 130 ms) increased from 0.43 at 4 h to 1.0 at 24 h after ROSC. Sensitivity decreased from 1.0 at 4 h to 0.83 at 24 h after ROSC.


CONCLUSIONS
Within 24 h after ROSC there was a significant improvement in SEP. Therefore we recommend allowing a period of at least 24 h after cardiopulmonary resuscitation for obtaining a reliable prognosis based on SEP.
Gendo
A
A
Department of Internal Medicine IV, Intensive Care Unit 13 H1, University of Vienna, Währinger Gürtel 18-20, 1090 Vienna, Austria. alexandra.gendo@univie.ac.at
Kramer
L
L
Häfner
M
M
Funk
G C
GC
Zauner
C
C
Sterz
F
F
Holzer
M
M
Bauer
E
E
Madl
C
C
D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D000704:Analysis of Variance; D001317:Austria / Q000453:epidemiology; D016887:Cardiopulmonary Resuscitation; D003128:Coma / Q000175:diagnosis* / Q000209:etiology / Q000401:mortality; D005073:Evoked Potentials, Somatosensory; D005260:Female; D006323:Heart Arrest / Q000150:complications* / Q000401:mortality; D006801:Humans; D008297:Male; D008875:Middle Aged; D011237:Predictive Value of Tests; D011379:Prognosis; D011446:Prospective Studies; D012680:Sensitivity and Specificity; D013997:Time Factors