Biochemical and Metabolic Changes in Arsenic Contaminated ...
POSTOPERATIVE METABOLIC CHANGES
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729 Annotations POSTOPERATIVE METABOLIC CHANGES THE metabolic effects of injury have not yet been fully defined. Starvation is widely believed to play only a small part in bringing about the increased urinary excretion of nitrogen and potassium and the reduced output of sodium; injury is supposed to be the most important single factor in producing these changes. But Dr. Abbott and his colleagues, whose report we publish this week, believe that operative trauma and anaesthesia are only minor factors and that dietary restriction, complications, previous nutritional state, and age are the major factors. They describe observations on the effects of chole- cystectomy in 11 women and 2 men who were placed on one of three types of dietary regimen for three days before and three days after operation; the two periods of observa- tion were divided by an intermission of three to four days during which an ordinary full diet was consumed. When 5% glucose solution alone was given for three days operation had little effect on the excretory pattern of sodium, potassium, or nitrogen. When sodium and potassium were administered in addition to glucose the postoperative variations were similar to those who received glucose only, except in one patient whose wound became infected. In a third group of patients 5% protein hydrolysate and 10% fructose were added to the glucose, sodium, and potassium. Although these patients produced larger volumes of urine than those in the other two groups their losses of sodium, potassium, and nitrogen and of body-weight were smaller. Nevertheless the protein and carbohydrate supplied were evidently not wholly adequate, because even in the control period there was a nitrogen deficit and some weight-loss. That so little metabolic disturbance follows uncompli- cated cholecystectomy is not very surprising and raises the question whether this operation causes sufficient damage to provide an adequate stimulus-adequate, that is to say, for present methods of measurement and detection of the items of postoperative metabolic variation. This doubt is strengthened by the distinct effect of a pyrexial complica- tion in one patient of the series, and by the authors’ statement that a larger metabolic disturbance is associated with severe blood-loss, necrosis, or injection. There is abundant evidence that after injury urinary nitrogen excretion is closely related to the previous state of protein nutrition and the plane of protein metabolism, and that in malnourished patients nitrogen excretion may increase little, if at all, even after very severe operations. In well- nourished patients, however, provided the surgical injury is sufficiently severe nitrogen output usually increases notably. Since in simple starvation the urinary nitrogen output usually declines and seldom increases, the large increase of nitrogen output which follows many major operations can hardly be attributed to inadequate diet. The report by Abbott et al. raises again the important question of what part intravenous therapy should play in postoperative treatment. The metabolic disturbances recorded here do not appear to demand intravenous therapy, which is expensive and not entirely free of the risk of complications, such as chemical thrombophlebitis. The argument for such treatment would be stronger if there were larger differences between control and post- operative periods, and between the group who received glucose, potassium, sodium, fructose, and protein hydro- lysate and the patients who received only glucose. Until much more is known about the metabolism and excretion of adrenal cortical hormones and their end-products little is to be gained by discussing the apparent conflict between the observations of Abbott et al. and of Moore et al.l and Steenburg et a1. on the relation of nitrogen balance to urinary hydroxycorticoid excretion. The postoperative metabolic disturbances are likely to be due, not solely to " permissive " adrenal-steroid activity or to local tissue damage, but rather to a combination of both- processes; and local damage is likely to prove the primary stimulus. 1. Moore, F. D., Steenburg, R. W., Ball, M. R., Wilson, G. M., Myrden, J. A. Ann. Surg. 1955, 141, 145. 2. Steenburg, R. W., Lennihan, R., Moore, F. D. ibid. 1956, 143, 180. 3. Department of Health for Scotland: Scottish Health Services Council. The Organisation of Laboratory Services. H.M. Stationery Office. 1958. 1s. LABORATORY SERVICES IN SCOTLAND LABORATORY services in Scotland have developed somewhat differently from those in England. Clinical pathology as practised in England is a recent development in Scotland, where in the past laboratory investigations on patients were carried out mainly by university depart- ments of pathology (which really meant morbid anatomy), bacteriology, and biochemistry; and in many hospitals hsematology is still a province of medicine rather than of pathology. Even now, a very large amount of the clinical- pathological work in Scotland is done by the university departments of pathology, and probably a larger propor- tion is done " postally " than in England; this is largely inevitable because of the sparseness of the population in many areas; but possibly there is still too much centralisa- tion in the university laboratories. Another difference is that there is no separate Public Health Laboratory Service, and public-health-laboratory work is carried out by the laboratories that are also responsible for the hospital laboratory work. A committee was set up by the Scottish Health Services Council in 1956 to consider the future of the laboratory service. In its report 3 this committee recommends that regional plans should be developed for the hospital patho- logical work, so that university departments should do only such routine work as is necessary for teaching and research. As regards administration of the laboratory services the committee, while admitting that a case could be made out for a regional pathological service centrally administered by the regional boards, felt that the existing service under the boards of management should be continued, but with the important difference that there should be more centra- lised planning of laboratory services by the regional boards with the advice of a strong pathological advisory committee, which would include members of the regional board, general practitioners, medical officers of health, and other consultants, in addition to pathologists. - The committee insists that boards of management must be prepared to take account of matters beyond the local interest of their particular hospitals and proposes that the laboratories under more than one board of manage- ment be grouped to provide a more comprehensive service. Although the expenditure on laboratories has increased proportionally nearly twice as much as expendi- ture in the hospitals generally, much still remains to be done; and the committee proposes that special revenue and capital allocations should be made to the regional boards for laboratory purposes and that regional boards should not have the power to divert these allocations to other purposes. Much of the report is of interest to hospitals in England and Wales. In particular a wider grouping of hospitals
Transcript of POSTOPERATIVE METABOLIC CHANGES
729
Annotations
POSTOPERATIVE METABOLIC CHANGES
THE metabolic effects of injury have not yet been fullydefined. Starvation is widely believed to play only a smallpart in bringing about the increased urinary excretion ofnitrogen and potassium and the reduced output of sodium;injury is supposed to be the most important single factorin producing these changes. But Dr. Abbott and his
colleagues, whose report we publish this week, believethat operative trauma and anaesthesia are only minorfactors and that dietary restriction, complications, previousnutritional state, and age are the major factors.They describe observations on the effects of chole-
cystectomy in 11 women and 2 men who were placed onone of three types of dietary regimen for three days beforeand three days after operation; the two periods of observa-tion were divided by an intermission of three to four daysduring which an ordinary full diet was consumed.When 5% glucose solution alone was given for three
days operation had little effect on the excretory patternof sodium, potassium, or nitrogen. When sodium andpotassium were administered in addition to glucose thepostoperative variations were similar to those whoreceived glucose only, except in one patient whose woundbecame infected. In a third group of patients 5% proteinhydrolysate and 10% fructose were added to the glucose,sodium, and potassium. Although these patients producedlarger volumes of urine than those in the other two groupstheir losses of sodium, potassium, and nitrogen and ofbody-weight were smaller. Nevertheless the protein andcarbohydrate supplied were evidently not wholly adequate,because even in the control period there was a nitrogendeficit and some weight-loss.That so little metabolic disturbance follows uncompli-
cated cholecystectomy is not very surprising and raises thequestion whether this operation causes sufficient damageto provide an adequate stimulus-adequate, that is to say,for present methods of measurement and detection of theitems of postoperative metabolic variation. This doubt isstrengthened by the distinct effect of a pyrexial complica-tion in one patient of the series, and by the authors’statement that a larger metabolic disturbance is associatedwith severe blood-loss, necrosis, or injection. There isabundant evidence that after injury urinary nitrogenexcretion is closely related to the previous state of proteinnutrition and the plane of protein metabolism, and that inmalnourished patients nitrogen excretion may increaselittle, if at all, even after very severe operations. In well-nourished patients, however, provided the surgical injuryis sufficiently severe nitrogen output usually increasesnotably. Since in simple starvation the urinary nitrogenoutput usually declines and seldom increases, the largeincrease of nitrogen output which follows many majoroperations can hardly be attributed to inadequate diet.The report by Abbott et al. raises again the important
question of what part intravenous therapy should play inpostoperative treatment. The metabolic disturbancesrecorded here do not appear to demand intravenoustherapy, which is expensive and not entirely free of therisk of complications, such as chemical thrombophlebitis.The argument for such treatment would be stronger ifthere were larger differences between control and post-operative periods, and between the group who receivedglucose, potassium, sodium, fructose, and protein hydro-lysate and the patients who received only glucose. Until
much more is known about the metabolism and excretionof adrenal cortical hormones and their end-products littleis to be gained by discussing the apparent conflict betweenthe observations of Abbott et al. and of Moore et al.land Steenburg et a1. on the relation of nitrogen balanceto urinary hydroxycorticoid excretion. The postoperativemetabolic disturbances are likely to be due, not solely to"
permissive " adrenal-steroid activity or to local tissuedamage, but rather to a combination of both- processes;and local damage is likely to prove the primary stimulus.
1. Moore, F. D., Steenburg, R. W., Ball, M. R., Wilson, G. M., Myrden,J. A. Ann. Surg. 1955, 141, 145.
2. Steenburg, R. W., Lennihan, R., Moore, F. D. ibid. 1956, 143, 180.3. Department of Health for Scotland: Scottish Health Services Council.
The Organisation of Laboratory Services. H.M. Stationery Office.1958. 1s.
LABORATORY SERVICES IN SCOTLAND
LABORATORY services in Scotland have developedsomewhat differently from those in England. Clinical
pathology as practised in England is a recent developmentin Scotland, where in the past laboratory investigations onpatients were carried out mainly by university depart-ments of pathology (which really meant morbid anatomy),bacteriology, and biochemistry; and in many hospitalshsematology is still a province of medicine rather than ofpathology. Even now, a very large amount of the clinical-pathological work in Scotland is done by the universitydepartments of pathology, and probably a larger propor-tion is done " postally
" than in England; this is largelyinevitable because of the sparseness of the population inmany areas; but possibly there is still too much centralisa-tion in the university laboratories. Another difference isthat there is no separate Public Health Laboratory Service,and public-health-laboratory work is carried out by thelaboratories that are also responsible for the hospitallaboratory work.A committee was set up by the Scottish Health Services
Council in 1956 to consider the future of the laboratoryservice. In its report 3 this committee recommends thatregional plans should be developed for the hospital patho-logical work, so that university departments should do onlysuch routine work as is necessary for teaching and research.As regards administration of the laboratory services thecommittee, while admitting that a case could be made outfor a regional pathological service centrally administeredby the regional boards, felt that the existing service underthe boards of management should be continued, but withthe important difference that there should be more centra-lised planning of laboratory services by the regionalboards with the advice of a strong pathological advisorycommittee, which would include members of the regionalboard, general practitioners, medical officers of health,and other consultants, in addition to pathologists. -
The committee insists that boards of managementmust be prepared to take account of matters beyond thelocal interest of their particular hospitals and proposesthat the laboratories under more than one board of manage-ment be grouped to provide a more comprehensiveservice. Although the expenditure on laboratories hasincreased proportionally nearly twice as much as expendi-ture in the hospitals generally, much still remains to bedone; and the committee proposes that special revenue andcapital allocations should be made to the regional boardsfor laboratory purposes and that regional boards shouldnot have the power to divert these allocations to other
purposes.Much of the report is of interest to hospitals in England
and Wales. In particular a wider grouping of hospitals
