[Critical illness myopathy and neuropathy (CRIMYN). Electroneurographic classification]

Abstract

Background: Critical Illness Myopathy and Neuropathy (CRIMYN) frequently coexist with severe sepsis and is associated with prolonged weaning from mechanical ventilation and prolonged ICU length of stay. We aimed to classify different levels as well as patterns of impairment with regard to electrophysiological disturbances in CRIMYN patients by cluster analysis.

Methods: A total of 30 patients with sepsis/SIRS were studied prospectively. Motor and sensory conduction studies were performed from six motor and four sensory nerves on a weekly basis from admission until discharge and finally after 6 months. A control group of 63 healthy persons was examined simultaneously using the same criteria. Different patterns of electrophysiological disturbances were classified by cluster analysis based on differences to reference values of 20 parameters, compound muscle action potential (CMAP), sensory nerve action potential (SNAP) and motor and sensor conduction velocity (NCV).

Results: Four different clusters were identified: cluster 1 showing normal values for CMAP, SNAP and NCV in all nerves (3 patients and all test persons), cluster 2 showing pathological values for CMAP in the lower extremities and the other parameters were normal (5 patients), cluster 3 showing moderately pathological values for CMAP, SNAP and sensory NCV in upper and lower extremities and motor NCV in lower extremities (12 patients) and cluster 4 showing severe disturbances of CMAP, SNAP and NCV in upper and lower extremities (10 patients).

Conclusion: A total of four different clusters of electrophysiological impairment can be identified in patients with sepsis/SIRS, which enables further differentiation of the severity of neuromuscular disturbances in sepsis-associated organ failure. This might be useful as a prognostic parameter and can be correlated with additional clinical and paraclinical parameters related to sepsis.