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The physiology and medicine of diving and compressed air work
BRITISH JOURNAL OF ANAESTHESIA
544
It seems apparent that the findings referred to in this paper are of particular importance to the consideration of subjects with hypo-albuminaemia, plus an increased serum volume: that is, pregnant women, probably women taking an oral contraceptive, and possibly newborn infants. In these subjects, as compared with the standard adult, a relatively greater proportion of a drug during its transport in serum will be bound to albumin, hence a smaller proportion (unbound) will be free for immediate transfer to the appropriate site of action. Thus the response to the drug will be diminished but protracted. The rate of metabolism and elimination will be slowed. It is worth reiterating, especially in respect to the neonates, that this is not a reflection of hepatic dysfunction. Finally, the possibility that a similar set of relationships governs the binding by albumin of naturally occurring substances, such as hormones and metallic ions, appears to offer a challenge to the practical and theorizing activities of the biochemists.
Effects. The effects which the changes in drug-binding capacity of albumin might have on the results of bromsulphthalein tests of hepatic function have already been discussed (Crawford and Hooi, 1968a). A more general discussion of the influence on pharmacodynamics would be concerned with the rates of distribution and elimination of drugs.
Crawford, J. S., and Hooi, H. W. Y. (1968a). Binding of bromsulphthalein by serum albumin from pregnant women, neonates and subjects on oral contraceptives. Brit. J. Anaesth., 40, 723. (1968b). Binding of salicylic acid and sulphanilamide in serum from pregnant patients, cord blood and subjects taking oral contraceptives. Brit. J. Anaesth., 40, 825. Seligson, D., Marino, J., and Dodson, E. (1957). Determination of sulfobromophthalein in serum. Clin. Ckem., 3, 638.
REFERENCES
BOOK REVIEW The physiology and medicine of diving and compressed air work. Edited by P. B. Bennett and D. H. Elliott. Published by Bail here Tindall and Cassell, London (1969). This book of more than 500 pages divided into twentyone chapters has a foreword by Professor Lambertsen in which he gives a fascinating account of the paths future developments in this subject can be expected to take. The twenty-five contributors are acknowledged experts in some field of compression work but except for one Swiss and one French they represent institutions in North America or the United Kingdom. Probably this is no fault of the editors; some countries are more jealous of their scientific discoveries than others, especially when they can be related to Defence programmes. This is unfortunate, because almost certainly the Russians and the Japanese for instance could have added to this formidable collection of data. The extent to which interest in the phenomena of
deep diving has developed in a variety of different disciplines is witnessed by the fact that contributions have come from chemists, engineers and physicists as well as from basic medical scientists and clinical scientists. And as might be expected they cover a wide range of topics from basic physical and physiological principles through design problems in apparatus to the clinical problems of compression and decompression. Anaesthetists in particular will find the chapters on oxygen toxicity, carbon dioxide effects, inert gas narcosis, the role of exotic gases in the study of narcosis and the feasibility of liquid-breathing and artificial gills well worth reading. The book is beautifully produced on good quality paper. The print is easy to read and the illustrations are particularly well done. It is in fact a pleasure to handle but at £8 per copy, except for the specialists, librarians are likely to be the main purchasers. J. P. Payne
Downloaded from http://bja.oxfordjournals.org/ at Florida Atlantic University on July 28, 2015
The percentage diminution in the number of molecules of drug bound per molecule of albumin when the concentration of albumin is raised from 3 per cent to 4 per cent among die group of subjects taking an oral contraceptive is: salicylic acid 8.8 per cent; bromsulphthalein 15.6 per cent sulphanilamide 23.9 per cent. The difference between the binding of bromsulphthalein by albumin from male and female controls, and by albumin from th; "pregnancy hormone group" (Crawford and Hooi, 1968a), reflected to some degree by a similar difference observed in the salicylic acid study (Crawford and Hooi, 1968b), is worthy of comment. Apparently it is heretical to suggest that hormonal influences can induce the production of albumin with properties differing from those of normally manufactured albumin, but this does appear to be the case here, and foetal serum albumin is well known to be different qualitatively from adult serum albumin.
544
It seems apparent that the findings referred to in this paper are of particular importance to the consideration of subjects with hypo-albuminaemia, plus an increased serum volume: that is, pregnant women, probably women taking an oral contraceptive, and possibly newborn infants. In these subjects, as compared with the standard adult, a relatively greater proportion of a drug during its transport in serum will be bound to albumin, hence a smaller proportion (unbound) will be free for immediate transfer to the appropriate site of action. Thus the response to the drug will be diminished but protracted. The rate of metabolism and elimination will be slowed. It is worth reiterating, especially in respect to the neonates, that this is not a reflection of hepatic dysfunction. Finally, the possibility that a similar set of relationships governs the binding by albumin of naturally occurring substances, such as hormones and metallic ions, appears to offer a challenge to the practical and theorizing activities of the biochemists.
Effects. The effects which the changes in drug-binding capacity of albumin might have on the results of bromsulphthalein tests of hepatic function have already been discussed (Crawford and Hooi, 1968a). A more general discussion of the influence on pharmacodynamics would be concerned with the rates of distribution and elimination of drugs.
Crawford, J. S., and Hooi, H. W. Y. (1968a). Binding of bromsulphthalein by serum albumin from pregnant women, neonates and subjects on oral contraceptives. Brit. J. Anaesth., 40, 723. (1968b). Binding of salicylic acid and sulphanilamide in serum from pregnant patients, cord blood and subjects taking oral contraceptives. Brit. J. Anaesth., 40, 825. Seligson, D., Marino, J., and Dodson, E. (1957). Determination of sulfobromophthalein in serum. Clin. Ckem., 3, 638.
REFERENCES
BOOK REVIEW The physiology and medicine of diving and compressed air work. Edited by P. B. Bennett and D. H. Elliott. Published by Bail here Tindall and Cassell, London (1969). This book of more than 500 pages divided into twentyone chapters has a foreword by Professor Lambertsen in which he gives a fascinating account of the paths future developments in this subject can be expected to take. The twenty-five contributors are acknowledged experts in some field of compression work but except for one Swiss and one French they represent institutions in North America or the United Kingdom. Probably this is no fault of the editors; some countries are more jealous of their scientific discoveries than others, especially when they can be related to Defence programmes. This is unfortunate, because almost certainly the Russians and the Japanese for instance could have added to this formidable collection of data. The extent to which interest in the phenomena of
deep diving has developed in a variety of different disciplines is witnessed by the fact that contributions have come from chemists, engineers and physicists as well as from basic medical scientists and clinical scientists. And as might be expected they cover a wide range of topics from basic physical and physiological principles through design problems in apparatus to the clinical problems of compression and decompression. Anaesthetists in particular will find the chapters on oxygen toxicity, carbon dioxide effects, inert gas narcosis, the role of exotic gases in the study of narcosis and the feasibility of liquid-breathing and artificial gills well worth reading. The book is beautifully produced on good quality paper. The print is easy to read and the illustrations are particularly well done. It is in fact a pleasure to handle but at £8 per copy, except for the specialists, librarians are likely to be the main purchasers. J. P. Payne
Downloaded from http://bja.oxfordjournals.org/ at Florida Atlantic University on July 28, 2015
The percentage diminution in the number of molecules of drug bound per molecule of albumin when the concentration of albumin is raised from 3 per cent to 4 per cent among die group of subjects taking an oral contraceptive is: salicylic acid 8.8 per cent; bromsulphthalein 15.6 per cent sulphanilamide 23.9 per cent. The difference between the binding of bromsulphthalein by albumin from male and female controls, and by albumin from th; "pregnancy hormone group" (Crawford and Hooi, 1968a), reflected to some degree by a similar difference observed in the salicylic acid study (Crawford and Hooi, 1968b), is worthy of comment. Apparently it is heretical to suggest that hormonal influences can induce the production of albumin with properties differing from those of normally manufactured albumin, but this does appear to be the case here, and foetal serum albumin is well known to be different qualitatively from adult serum albumin.