Evaluation of Muscle Strength by Transcutaneous Electrical Stimulation in Intensive Care Unit Patients

Acquired Neuromyopathy of Resuscitation (NMAR) is a common condition. Its diagnosis is difficult and often late because it is based on a clinical assessment of muscle strength (MRC score) requiring the patient to be awake and cooperative.

Transcutaneous electrical stimulation consists of applying electrical stimulation along the path of a motor nerve in order to generate contraction of the previously relaxed muscle. The mechanical response thus generated is recorded and allows the muscular strength developed to be assessed. Non-invasive and easily performed in the patient's bed, transcutaneous electrical stimulation could be an interesting alternative for early assessment of muscle strength in the still sedated resuscitation patient. However, this technique could be perceived as uncomfortable or painful in the awake patient so that magnetic stimulation, which is generally much better tolerated, should be preferred. However, magnetic stimulators have a limited maximum magnetic field which may prevent supramaximal stimulation especially in patients developing generalized edema (i.e., in the initial resuscitation phase).