Protective effect of lidocaine in acute cerebral ischemia induced by air embolism

Abstract

To investigate possible approaches to the prevention and treatment of neural damage induced by air embolism and other forms of acute cerebral ischemia, a model was used in which cerebral air embolism was produced by infusion of air (0.4 ml) into a vertebral artery of chloralose-anesthetized cats. Neurological function was assessed by measuring cortical somatosensory evoked responses in a group of 10 untreated animals and in a group of eight animals pretreated with intravenous lidocaine (5 mg/kg). In the untreated group, the primary somatosensory amplitude was reduced to 28% +/- 9% (mean +/- standard error) of the value before air embolism, with a return to 60% +/- 8% 1 hour and 73% +/- 12% 2 hours after embolism. In the group pretreated with lidocaine, the primary somatosensory amplitude was reduced to 68% +/- 9% of the value before air embolism, with a return to 92% +/- 3% 1 hour and 97 +/- 2% 2 hours after embolism. Pretreatment with lidocaine also greatly attenuated the acute hypertension and the increase in intracranial pressure following air embolism. These results demonstrate that pretreatment with intravenous lidocaine significantly reduces the neural decrement and increases the recovery of neural function after acute cerebral ischemia induced by air embolism.

Pharmacological Interventions to Decompression Sickness in Rats: Comparison of Five Agents

“…It readily crosses the blood-brain barrier (43), has a high volume of distri bution, and is rapidly metabolized by the liver. In 1984, Evans et al (18) demonstrated a protective effect of lido caine in a feline model of cerebral arterial gas embolism, sparking interest as a potential adjuvant treatment for DCS (18). A rat study found predive intraperitoneal in jections of lidocaine reduced DCS from 72-0% (31).…”

Intravenous Lidocaine as Adjunctive Therapy in the Treatment of Decompression Illness

“…1 To date, no effective adjunctive therapies have been identified, although some studies have supported the use of lidocaine in neurologic injuries. 2- 5 The cases described here suggest a beneficial effect of IV lidocaine when used as an adjunct to HBOT in severe decompression illness.…”

An evaluation of the effect of lidocaine in experimental focal cerebral ischemia.

“…In support of a protective effect of lidocaine, Evans et al 4 observed that neurological function (as assessed by cortical somatosensory evoked response) was substantially preserved following cerebral air embolism in the animals that received a single prophylactic dose (5 mg/kg) of lidocaine. Considering that in dogs, this dose produced less than a 30% reduction in CMR0 2 , the reported effect on SER's appeared dramatic and in excess of what can be predicted from neurochemical studies.…”

“…Further investigation in this direction was undertaken by Evans et al 4 Utilizing an experimental model of cerebral ischemia produced by arterial air embolism, ischemic depression of cortical somatosensoryevoked responses was shown to be considerably attenuated by prophylactic intravenous administration of lidocaine 5 mg/kg. The value of this drug in other models of cerebral ischemia needs to be investigated.…”