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 SPOEREL, W. E.
Right arrow Articles by BAIN, J. A.
Right arrow Search for Related Content
PubMed
Right arrow Articles by SPOEREL, W. E.
Right arrow Articles by BAIN, J. A.

Canadian Journal of Anesthesia, Vol 25, 30-35, Copyright © 1978 by Canadian Anesthesiologists' Society

Spontaneous Respiration with the Bain Breathing Circuit

W. E. SPOEREL 1, R. R. AITKEN 1, and J. A. BAIN 1

1 Department of Anaesthesia, University of Western Ontario, University Hospital and Victoria Hospital, London, Ontario

Although the Mapleson A system (Magill attachment) is more efficient in spontaneously breathing patients under anaesthesia, our clinical experience has shown that the Mapleson D system (Bain circuit) can be used safely for spontaneous respiration under suitable conditions. In 113 craniotomies under general anaesthesia with spontaneous breathing a mean PaCOCO2: of 39 ± 6 mm Hg was obtained with a fresh gas flow (FGF) ranging from 90 to 160 ml/kg; there was no difference between 15 patients with FGF of 93 ± 4 ml/kg/min and a PaCOCO2, of 40 ± 6 mm Hg and 15 patients maintained on the highest FGF of 143 ± 11 ml/kg/min with a PaCOCO2 of 39 ± 5 mm Hg.

Comparing the Bain circuit with the Magill attachment and the circle absorber in 101 unpremedicated young adults undergoing oral surgery under endotracheal anaesthesia with nitrous oxide and halothane or enflurane, we found the Bain circuit with 100 ml/kg/min (RMV 20 per cent higher than circle absorber, PaCOCO2 40 ± 4 mm Hg) equally efficient than the Magill attachment with a FGF of 70 ml/kg/min (RMV 17 per cent higher than the circle absorber, PaCOCO2 39 ± 6 mm Hg). In the Bain circuit greater rebreathing by a reduction of the FGF to 70 ml/kg/min produced a 57 per cent rise in RMV with a PaCOCO2, of 42 ± 4 mm Hg; a slower respiratory rate induced by substituting enflurane for halothane did not improve the efficiency of the Bain circuit. In all patients the surgical stimulation induced about a ten per cent increase in RMV, inducing mild hypocapnia with the circle absorber (PaCOCO2 35 ± 5 mm Hg) and the Bain circuit with FGF of 140 ml/kg/min (PaCOCO2 36 ± 3 mm Hg). It is concluded that suitable patients, anaesthetized to retain an adequate CO2 response, can be allowed to breathe spontaneously with the Bain breathing circuit.

Note:

Presented at the Annual Meeting of the Canadian Anaesthetists' Society, Saskatoon, June 20-23, 1977.






HOME HELP FEEDBACK SUBSCRIPTIONS ARCHIVE SEARCH TABLE OF CONTENTS
Copyright © 1978 by the Canadian Anesthesiologists' Society.