Clinical and biochemical features of aromatic l-amino acid decarboxylase deficiency

N20. Two more recent studies on N20 in cardiac arrest patients have found 0% false-positive rates (reporting on 13 and 33 patients, respectively). 3,6 In view of these recent studies, we agree with Dr. Rothstein that SSEPs are a valuable prognostic parameter, even in hypothermia patients.Pooled analysis of the mentioned SSEP studies on hypothermia patients 1,2,3,6 gives a 1.2% false-positive rate (1/85), which falls within the 95% confidence interval for nonhypothermia patients. 8 However, a potential bias remains.As prognostic parameters established in nonhypothermia patients are used for treatment decisions, studies on hypothermia patients could become a self-fulfilling prophecy 6 ; if bilateral negative N20 leads to withdrawal of care, its predictive value for poor outcome might be overestimated.While recent studies-including our own-suggest that only a small minority of patients may recover despite absent N20, it is important to establish this fact more reliably.Finally, the timing of SSEP recordings after cardiac arrest should be reevaluated to avoid false decisions in individual patients.