Barbiturates in Brain Ischaemia

Abstract

This review has indicated that barbiturates are useful in controlling ICP during anaesthesia in patients with intracranial hypertension. While laboratory data indicate that intraoperative administration of barbiturates during episodes of transient cerebral ischaemia, associated with surgical revascularization procedures, should be efficacious, current intraoperative results claiming benefit are anecdotal. Continuous high-dose barbiturate therapy (induced barbiturate coma) for occlusive stroke and persistently increased intracranial pressure is currently undergoing clinical trials. While it is clear that this therapy can often reduce increased ICP in head injured patients, its influence on neurological outcome remains to be determined by a multicentre trial at present in progress. Despite evidence that high-dose barbiturate therapy can reduce the area of infarction in occlusive stroke in the laboratory, organized clinical trials have not yet commenced. Until more definitive knowledge is available concerning the influence of high-dose barbiturate therapy in treating different forms of cerebral ischaemia, its application should be viewed sceptically and limited to centres willing to create an organized data base for inter-institutional evaluation of this form of treatment. If barbiturate therapy proves successful and the mechanisms involved are better understood, drugs with fewer side-effects and risks may become available to combat cerebral ischaemia.

Pharmacological agents as cerebral protectants during deep hypothermic circulatory arrest in adult thoracic aortic surgery

“…The use of thiopental during deep hypothermic circulatory arrest is based on animal studies of ischaemia models and on its clinical use in a neurosurgical setting. These data have been reviewed by Shapiro and Belopavlovic & Buchthal [5,6]. Some animal studies have shown a decrease in infarct volume, neurological deficit and death after deep hypothermic circulatory arrest in a variety of species pretreated with high-dose thiopental (50 mg.kg )1 ).…”

Secobarbital Attenuates Excitotoxicity but Potentiates Oxygen—Glucose Deprivation Neuronal Injury in Cortical Cell Culture

“…Animal plasma lev els as high as 380 f.LM (Hoff et al, 1975) and brain levels as high as 200 f.LM (Krieglstein et al, 1981) have been reported. In human trials with thiopental, serum concentrations of 60--200 f.LM have been doc umented (Shapiro, 1985).…”

“…, 1981Selman et aI. , , 1982 have also been re ported (reviewed by Piatt and Schiff, 1984;Shapiro, 1985;Trauner, 1986). Clinical studies have sug gested that barbiturates are not helpful in patients suffering cardiac arrest (Abramson et aI., 1986) or head trauma (Ward et aI., 1985).…”

Cerebral Pressure Autoregulation and Carbon Dioxide Reactivity During Propofol-Induced EEG Suppression

“…anaesthetic agents depress also cerebral metabolism in a dose-dependent manner. As typified by the barbiturates, this depression is associated with a reduction in cerebral metabolic requirements for oxygen (CMRo 2 ) and CBF, which stabilize when electroencephalographic (EEG) activity becomes isoelectric [6,7]. Barbiturate-induced cortical suppression has been advocated as a method of cerebral protection during temporary occlusion of any vessel that provides nutrients to the central nervous system [8].…”