Early detection of ICU-acquired weakness in septic shock patients ventilated longer than 72 h

ICU-acquired weakness, comprising Critical Illness Polyneuropathy (CIP) and Myopathy (CIM) is associated with immobilization and prolonged mechanical ventilation. This study aims to assess feasibility of early detection of CIP and CIM by peroneal nerve test (PENT) and sensory sural nerve action potential (SNAP) screening in patients with septic shock and invasively ventilated for more than 72 h.

We performed repetitive PENT screening from 72 h after intubation until detecting a pathological response. We tested SNAPs in pathological PENT to differentiate CIP from CIM. We performed muscle strength examination in awake patients and recorded time from intubation to first in-bed and out-of-bed mobilization.

Eighteen patients were screened with PENT and 88.9% had abnormal responses. Mean time between intubation and first screening was 94.38 (± 22.41) hours. Seven patients (38.9%) had CIP, two (11.1%) had CIM, one (5.6%) had CIP and CIM, six (33.3%) had a pathological response on PENT associated with ICU-acquired weakness (but no SNAP could be performed to differentiate between CIP and CIM) and two patients had (11.1%) had no peripheral deficit. In patients where it could be performed, muscle strength testing concorded with electrophysiological findings. Twelve patients (66.7%) had out-of-bed mobilization 10.8 (± 7.4) days after admission.

CIP and CIM are frequent in septic shock patients and can be detected before becoming symptomatic with simple bedside tools. Early detection of CIP and CIM opens new possibilities for their timely management through preventive measures such as passive and active mobilization.