Korean J Anesthesiol.  1971 Jan;4(1):27-34.

Effects of Thiopental Sodium on Oxygen Consumption in the Rabbit

• Park DH
• Oh HK

Abstract

It is generally accepted that barbiturates reduce the whole body oxygen consumption (Vo2). However Theye (1970) reported that in dog experiments during halothane anesthesia, a single injection of thiopental (10 mg/kg) did not produce significant change in Vo2 and in unpremedicated human subjects Vo2 decreased an average of 7% with administration 1 gm of tbiopental over a period of approximately 15 to 20 minutes. Thus, according to Theye, the difference between the effect of thiopental on the Vo2 of man & of dogs is believed to be based upon the difference in relative magnitudes of Vo and eerebral oxygen consumption in the two species. Therefore, we have studied the effect of thiopental sodium on the Vo2 of rabbits and the difference in effects of three pharmaceutical preparations. Unpremedicated rabbits (43) averaging 1.8 kg. were utilized in this study. Just before and 2-5 min. after intravenous administration of thiopental sodium (30 mg/kg.), Vo2 by the modified closed chamber apparatus of Morrison was measured, respiratory rate visually and by the plethysmograph and heart rate by E.K.G. And the recovery process was observed. The results were as follows. 1. Vo2 was significantly decreased following thiopental administration, using different preparations, 29% with Abott Pharm. Co. LTD. (Group I), 22% with Daihan Choong-Wae Pharm. Ind. Co. LTD. (Group II) and 19% with Asia Pharm. Co.LTD. (Group III), respectively. 2. The respiratory rate was markedly reduced (an average fall of 72%) after thiopental administration, but tidal volume was increased. 3. E.K.G. pattern and heart rate were not significantly altered except for a significant decrease in heart rate in group II. 4. In recovery process, eye lid reflex was regained within 1 min. following thiopental in group I & III but after 3 4 min. in group The recovery periods of positive head lift test, crawling & working following thiopental were prolonged (average 27.3, 46.3 & 57.3 min. respectively) in group I, about twice as long as in group II & III.

MeSH Terms

Administration, Intravenous
Anesthesia
Animals
Asia
Barbiturates
Dogs
Halothane
Head
Heart Rate
Humans
Oxygen Consumption*
Oxygen*
Pharmaceutical Preparations
Rabbits
Reflex
Respiratory Rate
Thiopental*
Tidal Volume
Barbiturates
Halothane
Oxygen
Pharmaceutical Preparations
Thiopental