Portal de Periódicos da CAPES

Influence of induction agent on pulmonary venous admixture during halothane: Oxygen anaesthesia with controlled respiration in man

1974; Springer Nature; Volume: 21; Issue: 5 Linguagem: Inglês

10.1007/bf03005840

0008-2856

Bryan E. Marshall, Doreen A. Hoffman, Gordon R. Neufeld, Ethan T. Colton,

Renal function and acid-base balance

In six healthy unpremedicated, adult male volunteers (mean age 23 years), cardiac index (CI) (mean = 2.91 ± S.E. 0.12 L/min/kg), alveolar-arterial oxygen tension difference (AaDo2) (mean = 38 ± S.E. 13 torr), and percent pulmonary venous admixture (Qs/Qc%) (mean = 2.94 ± S.E. 0.51%) were measured breathing 100 per cent oxygen (Phase 1). Anaesthesia was then induced either with thiopentone (3 mg/kg) (Phase 2) or halothane:oxygen (Phase 3) and maintained in both cases with oxygen:halothane for one hour with mechanical ventilation. Halothane was then discontinued until awakening and anaesthesia reinduced with the agent not previously used, and measurements of Phases 2 and 3 repeated after another one hour. Temperature, PaCo2, ventilation, cardiac output, and blood pressure were unchanged. The efficiency of oxygen exchange in the lungs following a thiopentone induction was significantly better than that following a halothane: oxygen induction. After thiopentone induction AaDo2 (mean = 38 ± S.E. 13 torr) and QsQc (mean = 2.99 ± S.E. 1.05%) were unchanged from the awake values, while following halothane:oxygen induction AaDo2 (mean = 48 ± S.E. 12 torr) and Qs/Qc (mean = 3.81 ± 1.2 torr) were significantly (P < 0.05) increased.