CJA
HOME HELP FEEDBACK SUBSCRIPTIONS ARCHIVE SEARCH TABLE OF CONTENTS
This Article
Right arrow Full Text (PDF)
Right arrow Submit a scholarly reply
Right arrow Alert me when this article is cited
Right arrow Alert me when eLetters are posted
Right arrow Alert me if a correction is posted
Services
Right arrow Similar articles in this journal
Right arrow Alert me to new issues of the journal
Right arrow Download to citation manager
Right arrow reprints & permissions
Citing Articles
Right arrow Citing Articles via Google Scholar
Google Scholar
Right arrow Articles by SWARTZ, J.
Right arrow Articles by BIEHL, D.
Right arrow Search for Related Content
PubMed
Right arrow Articles by SWARTZ, J.
Right arrow Articles by BIEHL, D.

Canadian Journal of Anesthesia, Vol 32, 577-582, Copyright © 1985 by Canadian Anesthesiologists' Society

The Effects of General Anaesthesia on the Asphyxiated Foetal Lamb in Utero

J. SWARTZ MD FRCPC1, M. CUMMINGS RN BSC1, W. PUCCI RT1, and D. BIEHL MD FRCPC1

1 Department of Anesthesia, University of Manitoba, Winnipeg, Manitoba

Address correspondence to: Dr. D. Biehl, Department of Anesthesia, St. Boniface General Hospital, 409 Tache Avenue, Winnipeg, Manitoba, R2H 2A6.

The effects of anaesthetic agents, per se, on the asphyxiated foetus are difficult to quantitate clinically. Anaesthesia is often necessary in foetal distress, however, to effect a rapid delivery. To investigate the effect of general anaesthetic agents commonly used for Caesarean section we administered these agents to 18 chronically prepared pregnant ewes with asphyxiated foetuses in utero. The foetuses were asphyxiated by partial occlusion of the umbilical cord until foetal arterial pH had decreased from 7.30 to a range of 7.08-7.13. The animals were divided into three groups: Group A which received no anaesthesia and thus served as a control, Group B which received thiopentone (3 mg·kg-1) intravenously followed by 50 per cent nitrous oxide and 0.5 per cent halothane in oxygen for 15 minutes, and Group C which received thiopentone (3 mg·kg-1) followed by one per cent halothane in oxygen for 15 minutes. Foetal cerebral, myocardial, and renal blood flows were measured by injection of radioactive microspheres after production of asphyxia and after 5 and 15 minutes of anaesthesia.

General anaesthesia in both groups B and C abolished the hypertension and bradycardia produced by foetal asphyxia secondary to umbilical cord occlusion. There were no significant differences between Groups B and C in foetal pH, PCO2, or PO2. Two foetuses in the nitrous oxide group died after ten minutes of anaesthesia, but the aetiology of the sudden demise is unclear. We conclude that general anaesthesia abolishes the foetal response to umbilical cord occlusion and does not improve foetal oxygenation or acid-base status.

Key Words: COMPLICATIONS: asphyxia • ANAESTHETICS, GASES: nitrous oxide • ANAESTHETICS, VOLATILE: halothane • ANAESTHESIA: obstetric • PREGNANCY: umbilical cord occlusion






HOME HELP FEEDBACK SUBSCRIPTIONS ARCHIVE SEARCH TABLE OF CONTENTS
Copyright © 1985 by the Canadian Anesthesiologists' Society.