Detection of critical illness polyneuropathy (CIP) in patients with severe sepsis using ultrasound of the muscle

Critical illness polyneuropathy is an often seen phenomenon in patients with severe sepsis in intensive care units. Its clinical manifestation is affection of the limb and respiratory muscles and causes weakness and complications in weaning from ventilation. CIP is a primary axonal neuropathy. Its leading electrophysiological sign is a reduction of CMAP and nerve action potential amplitudes. In a small feasibility study we are looking for structural changes in muscle structure and for spontaneous activity in the muscle, e.g. fasciculation, using ultrasound. We use an ultrasound scanner with 9–12 Mhz and are comparing proximal vs. distal muscle groups of all extremities and the thoracic axe at the onset of clinical symptoms and at different time points later. Moreover we compare these results with electrophysiological measurements of nerves. So far we found, that the majority of patients with electrophysiological signs of CIP showed spontaneous activitiy/fasciculation in ultrasound, that could not be seen in clinical examination. Almost all patients had structural changes in the muscle like edema and atrophy. In conclusion, ultrasound of the muscle could be an easy method to detect signs of CIP without electromyography and electroneurography and to look for structural changes in muscle texture. Therefore, it is an easily applicable, non-invasive diagnostic tool in the intensive care setting. Furthermore it could be a method to look for muscular recovery and regeneration during rehabilitation. (This work was supported by the Center of Sepsis Control&Care (CSCC), funded by the German Federal Ministry of Education and Research (BMBF) grant no. 01 E0 1002.)