Assessment of severity and time course of critical illness neuropathy in septic patients: a prospective observational study.

OBJECTIVE: In this prospective observational study we investigated electrophysiological alterations in the early phase of critical illness and correlated electrophysiological findings with the clinical picture and outcome.

METHODS: We enrolled 21 critically ill surgical patients having ≥ 12 Acute Physiology and Chronic Health Evaluation (APACHE) II scores on admission. Routine non-invasive bilateral electroneurography (ENG) examination of median and ulnar nerves was done on five consecutive days starting in two days after admission. Then weekly follow-up was performed. Motor and sensory nerve conduction indices were calculated and correlated with APACHE II and Simplified Acute Physiology Score II severity scores.

RESULTS: On the first examination 18/21 patients had > 20% reduction in the motor and sensory nerve conduction indices. Severity score systems showed significant negative correlation with the daily change of CMAP and SNAP amplitudes and calculated nerve conduction indices (Spearman's correlation, p < 0.001). Mortality was higher in the patients with worse admission ENG and/or stagnant electrophysiological status or declining tendency in the first week.

CONCLUSIONS: Electrophysiological alterations appeared soon after the development of critical illness. Early phase alterations showed a strong correlation with patients' general condition and more severe electrophysiological alterations predisposed to higher mortality. In several cases early alterations proved to be reversible.