Electrodiagnostic Findings in COVID-19 ICU Survivors

Background The long-term effects of COVID-19 on the peripheral nervous system remain incompletely understood. The objective of this study is to characterize electrodiagnostic findings in COVID-19 survivors who required intensive care admissions resulting in persistent weakness and marked functional impairments. Methodology A retrospective chart review was conducted on patients who were referred for electrodiagnostic testing between May 2020 and May 2021 and had persistent weakness. This cohort consisted of nine patients: seven males and two females, between 31 and 75 years old. Results Nerve conduction studies revealed absent sensory responses in at least one sampled nerve in all patients and absent motor responses in at least one sampled nerve in seven patients. Electromyography in all nine patients demonstrated neuropathic denervation, evidenced by varying degrees of fibrillation potentials and positive sharp waves, as well as long-duration, polyphasic motor units and reduced, neuropathic recruitment. None of the patients had electromyographic evidence of myopathy. Conclusions Overall, the electrodiagnostic findings are most consistent with a distal mixed sensorimotor axonal polyneuropathy as the primary pathological process underlying persistent weakness in this cohort. This pattern is consistent with critical illness polyneuropathy and may represent a form of peripheral nerve injury related to severe COVID-19 infection. Further research is needed to better characterize the long-term outcomes and underlying peripheral nerve pathophysiology of COVID-19-associated critical illness polyneuropathy. This may provide important insights into prevention and treatment strategies.