Shivering is a thermoregulatory response to low ambient temperature, isoflurane, or epidurally administered anesthetic agents. Paroxysmal hypothermia with shivering may be part of acute neurologic disorders. Often there is no clear localized anatomic substrate but in some conditions there is involvement of the periaqueductal gray (Wernicke encephalopathy).1
Shivering in comatose patients has received very little attention. Currently, shivering in comatose survivors of cardiopulmonary resuscitation is usually observed during hypothermia treatment but, long before the widespread introduction of this treatment modality, shivering had been reported in the immediate hours and days after anoxic-ischemic injury. In one study, “rhythmic rapid low amplitude movements” were noted in the legs, all limbs, jaw, and tongue; however, these patients had prior electrographic evidence of partial or myoclonic seizures.2