PURPOSE: The study was conducted to examine the usefulness of somatosensory evoked potentials (SEP) and proton magnetic resonance spectroscopy (1H-MRS) in predicting poor outcomes for comatose survivors after cardiopulmonary resuscitation. METHODS: We investigated 36 patients who were comatose after cardiac arrest. Among them, 35 had short latency SEP, and 27 had 1H-MRS. Both tests were performed in 26 patients. To estimate the cerebral outcome, we used the cerebral performance category (CPC) to classify the outcomes for our patients as good (CPC 1-2) or poor (CPC 3-5). RESULTS: Of the 36 patients, 11(31%) presented with good outcomes (CPC 1-2). A bilaterally absent N20 peak (n=35) predicted poor outcomes with a sensitivity of 54.2% and a specificity of 100%. A lactate-positive resonance (n=27) predicted poor outcomes with a sensitivity of 78.9% and a specificity of 100%. Using a combination of a bilaterally absent N20 peak and a lactate-positive resonance (n=26) predicted poor outcomes with a sensitivity of 94.4% and a specificity of 100%. CONCLUSION: The combination of a bilaterally absent N20 peak and a lactate-positive resonance is better than either alone in predicting poor outcomes in patients who are comatose after cardiac arrest.
Cardiopulmonary Resuscitation* ; Coma* ; Evoked Potentials, Somatosensory* ; Heart Arrest ; Humans ; Magnetic Resonance Spectroscopy* ; Protons* ; Sensitivity and Specificity ; Survivors*

PURPOSE: The objective of this study was to investigate whether proton magnetic resonance spectroscopy (1H-MRS) is useful in the prediction of the neurological outcome for comatose patients after successful cardiopumonary resuscitation (CPR). METHODS: We prospectively studied 22 patients with a comatose mentality existing for longer than 1 day after cardiac arrest. 1H-MRS examinations were scheduled to be performed within 5 days after restoration of spontaneous circulation (ROSC). All 1H-MRS readings were performed by a neuro-radiologist blindly. The best cerebral performance category (CPC) during 6 months after ROSC was used as the final outcome and classified as good (CPC 1-2) or poor (CPC 3-5). RESULTS: Elevated cerebral lactate resonances were found in 14 patients. All of the 14 lactate-positive patients experienced a poor outcome. Five of the 8 lactate-negative patients recovered without neurologic defects, but three of them suffered from severe neurologic defects. The elevated cerebral lactate resonance distinguished between good out-comes (n=5) and poor outcomes (n=17) with three false negatives (sensitivity 82%) and no false positives (specificit y 100%). Demonstration of brain lactate in 1H-MRS (p < 0.05) proved to be significant in terms of a poor prognosis. CONCLUSION: 1H-MRS is of great benefit in the prognostic evaluation of comatose patients with anoxic-ischemic encephalopathy after successful CPR.
Brain ; Cardiopulmonary Resuscitation* ; Coma* ; Heart Arrest ; Humans ; Hypoxia-Ischemia, Brain ; Lactic Acid ; Magnetic Resonance Spectroscopy* ; Prognosis ; Prospective Studies ; Protons* ; Reading ; Resuscitation