Abdominal aortic cross-clamping. Metabolic and hemodynamic consequences
M. C. Damask, C. Weissman, J. Rodriguez, J. Askanazi, S. H. Rosenbaum and A. I. Hyman
We address the question of whether an oxygen debt develops during a period
of abdominal aortic cross-clamping that may explain observed hemodynamic
changes. Group 1 received morphine sulfate (1 mg/kg) during induction of
anesthesia. Group 2 received same dose of morphine sulfate. Group 3
received 4 mg/kg of morphine sulfate. We measured the oxygen consumption
(VO2) and the carbon dioxide production levels (VCO2), as well as
hemodynamic and biochemical parameters. In groups 1 and 3, VO2 and VCO2
decreased 10% to 13% following abdominal aortic cross-clamping compared
with values measured before cross-clamping. In group 2, VO2 and VCO2
decreased 3% and 7%, respectively. On unclamping, the greatest increase in
VO2 was observed in group 3 (26%), while in groups 1 and 2, VO2 rose 18%
and 5%, respectively. In all three groups, metabolic changes were not
paralleled by hemodynamic or temperature changes. Results indicate that
oxygen debt developed during abdominal aortic cross-clamping, but this has
no effect on hemodynamic changes seen after unclamping. Higher dosage of
narcotic administered during anesthetic induction did not temper increase
in metabolic rate observed after unclamping.
