No significant changes were found in heart rate, blood pressure, cardiac output, arterial blood gases or physiological deadspace: tidal volume ratio before and after clamping and unclamping the abdominal aorta below the renal vessels. Nevertheless, drugs should be available to reduce the afterload on the heart if any evidence of myocardial ischaemia appears during the period of aortic clamping. The importance of maintaining an adequate circulating blood volume at all times is stressed.
References
1.
AdamsA. P. (1970): “The effects of mechanical ventilation on gas transfer within the lungs”, Ph.D. Thesis. University of London.
2.
AttiaR. R., MurphyJ. D., SniderM., LappasD. G., DarlingR. C., and LowensteinE. (1976): “Myocardial ischaemia due to infrarenal aortic cross-clamping during aortic surgery in patients with severe coronary artery disease”, Circulation, 53, 961.
3.
BrantA. B., ArmstrongR. P., and VettoR. M. (1970): “Vasodepressor factor in declamp shock production”, Surgery, 67, 650.
4.
CarrollR. M., LaravusoR. B., and SchaubleJ. F. (1976): “Left ventrical function during aortic surgery”, Arch. Surg., 111, 740.
5.
EnghoffH. (1938): “Volumen inefficax. Bermerkungen zur Frage Schädlichen Raumes”, Uppsala Lak-Fören Förk, 44, 191.
6.
KelmanG. R., and SunnJ. F. (1966): “Nomograms for correction of blood PO2, PCO2, pH and base excess for time and temperature”, J. appl. Physiol., 21, 1484.
7.
LumleyJ., MorganM., and SykesM. K. (1969): “Changes in arterial oxygenation and physiological deadspace under anaesthesia”, Brit. J. Anaesth., 41, 279.
8.
MelocheR., PottecherT., AudetJ., DufresneO., and LePageC. (1977): “Haemodynamic changes due to clamping of the abdominal aorta”, Canad. Anaesth. Soc. J., 24, 20.
9.
MorganM., LumleyJ., and SykesM. K. (1970): “Arterial oxygenation and physiological dead-space during ‘anaesthesia. Effects of ventilation with a pressure preset ventilator”, Brit. J. Anaesth., 42, 379.
10.
MorganM., LumleyJ., and GilliesI. D. S. (1974): “Neurolept-anaesthesia for major surgery. Experience with 500 cases”, Brit. J. Anaesth., 46, 288.
11.
NunnJ. F. (1963): “Indirect determination of the ideal alveolar oxygen tension during and after nitrous oxide anaesthesia”, Brit. J. Anaesth., 35, 8.
12.
PerryM. O. (1968): “The hemodynamics of temporary abdominal aortic occlusion”, Ann. Surg., 168, 193.
13.
SchneiweissR., HadsallF., and GordonH. E. (1966): “Prevention of hypotension following release of aortic occlusion”, Surgery, 60, 628.
14.
SimonsR. S., and WhiteY. (1976): “Computer-facilitated measurements from cardiac output indicator dilution curves”, Brit. J. Anaesth., 48, 275.
15.
SykesM. K. (1969): “A pressure-operated collect valve for respiratory studies during intermittent positive pressure ventilation”, Brit. J. Anaesth., 41, 189.
16.
VettoR. M., and BrantB. (1968): “Control of declamping shock”, Ann. Surg., 116, 273.
