980

followed, in the 2nd and 3rd centuries B.C., by thereactionary Empirics who, though they were mainlyconcerned with treatment, had the idea of a syndrome.And a century or so later came the Methodists whosimplified everything by classifying all diseases accordingto the state of the pores : relaxed pores called forastringents and constricted pores for laxatives, so thattreatment was very simple. From these early beginningsthe idea of deviation from normal had to await thedevelopment of anatomy and physiology before it madesubstantial progress ; and things did not begin to moveuntil the 16th and 17th centuries. Physics and chemistrythen began to play their part in disclosing the deviationfrom normal, and Sir Henry particularly emphasised thesignificant effect on medical thought of the synthesis ofurea in 1828, which showed clearly and for the first timethe relevance of chemistry to medicine. The discoveriesof the 19th century brought increasing knowledge of thenormal and departures from it ; but there was still therisk of interpreting such newly recognised conditions ashyperchlorhydria, hypertension, and polycythsemia as

distinct entities. ,

Turning to the present scene, Sir Henry declared thatthe concept of disease as a deviation from normal shoulddominate our teaching and our approach to medicine.The constant patterns-the syndromes or symptom-complexes-in which symptoms and signs appearedalways indicated one or more of three aspects of disease :its site, the associated functional disturbances, and thecausative factors. Specific and common patterns couldconveniently be regarded as entities, but there weredangers in giving too much scope to this view, whichlulled the doctor into being satisfied with a label andreduced thought to a minimum. Philosophic inquiry inmedicine was apt to be regarded as an arduous eccen-tricity for which few physicians today had either theopportunity or the inclination. But it was, Sir Henryconcluded, a worthwhile pursuit, for it helped to keep abalance between our dogmatism on the one hand andour scepticism and discouragement on the other. Aboveall, it inculcated humility in the presence of great mindswhich was the surest shield against intellectual arrogance.

1. Gamble, J. L. Pediatrics, Springfield, 1953, 11, 554.2. Marriott, W. M. The Harvey Lectures. Series 15. 1919-20 ;

p. 121.3. Macdonald, W. B. Med. J. Aust. 1953, ii, 197.4. Dods, L. Ibid, p. 226.

DEHYDRATION IN INFANTS

THE last few years have seen rapid developments influid and electrolyte therapy based on physiologicalprinciples established during the past three decades.But treatment by fluid replacement is over a hundredyears old, for the first reported cases were treated byDr. Latta during a cholera epidemic in Scotland in 1832.1Progress thereafter was slow, but, following the workof Marriott 2 on dehydration in infancy, fluid replace-ment speedily established itself as of outstanding impor-tance in the treatment of many diseases-and especiallythose producing diarrhoea in infants. At the annual

meeting of the Australian Psediatric Association earlierthis year the present position of this method of treatmentin infants. was reviewed in four papers that have nowbeen published. Macdonald,3 dealing with the physio-logical principles involved in the maintenance of thefluid and electrolyte balance in infancy, emphasises theimportance of using the correct terminology in discussingelectrolytes. But, as Dr. Ennis points out in our corres-pondence columns this week, many clinicians do not takekindly to the milli-equivalent and prefer to stick to thefamiliar " milligrammes per 100 ml." They are reprovedfor their reluctance to move with the times by ProfessorDods,4 who pointed out at the Australian meeting that " itwas only by talking and thinking in these terms of chemi-cal equivalence that they could have any real concept of

electrolyte patterns. Without this concept of electrolyteanatomy, any discussion of the problem must necessarilybe vague and nebulous."The electrolyte pattern of the newborn infant differs

from that of an adult in several ways.5 The potassium,chloride, sulphate, and phosphate content of the plasma ishigher and the bicarbonate and protein levels are lower. Inthe premature baby the bicarbonate level is even lowerthan in the full-term newborn, and the tendency to acid-osis that is present in all newborn babies is more definite.The control of acid-base equilibrium is often unstableand the regulating mechanism of the kidney is incom.pletely developed. Campbell 5 points out that late tyingof the cord may add from 3 to 31/2 ounces of blood tothe baby’s circulation, equivalent to giving a 10-stoneadult a blood-transfusion of 31/3 pints. She advocatesdelayed feeding of newborn infants, whether prematureor full-term, principally in order to give the babies rest.Premature babies begin to look dehydrated at forty-eighthours and Campbell advises that the administration of £fluids should begin then, especially if theinfant is muchjaundiced : fluids should be given parenterally if theinfant is not taking too well by mouth. In her view thehigh serum-bilirubin, together with low blood-glucoselevel, may be dangerous to brain tissue and is a possiblecause of " premature kernicterus. " 6 7 Williams,8 dis-

cussing the management of dehydration in enterocolitis,also emphasises that assessment can be made largelyon the clinical evidence and that biochemical tests arenot essential in the early acute phase. The Australianrecommendations for treatment are similar to those

given in the recent Medical Research Council memoraii-dum on the treatment of acute dehydration in infancy.9One important point is that potassium depletion is likelyto occur if long-continued intravenous therapy is givenwithout the administration of potassium.10

Finally, Stuckey 11 deals with the surgical aspects ofdehydration in infancy and childhood, with particularreference to high intestinal obstruction. Dehydrationin these patients is due partly to the abnormal lossesof intestinal secretions by vomiting, aspiration, or

fistulae, and partly to the failure to take or retain normalamounts of fluids by mouth. Treatment is planned infour phases. The first step is resuscitation, either fromsurgical shock or from severe dehydration. Stuckeyfavours blood or serum given fairly quickly ; he does notmention plasma, which is more commonly used in thiscountry. If dehydration is severe the protein-containingfluid is followed up with glucose-saline solution. Thesecond phase is concerned with the correction of moderatedehydration over the next twenty-four hours with

replacement fluids, in amounts equal to 6% of the body-weight, followed by maintenance fluids, in amounts up to15% of the body-weight daily. Stuckey recommends thatthe replacement fluid should contain potassium as well assodium, but some -may question the routine use of potas-sium at this stage. The third phase, starting on the secondday of treatment, consists in making up any deficit and inmaintaining fluid and electrolyte balance. On the thirdand subsequent days the balance is maintained and

protein or amino-acids are given. Throughout a constantcheck is kept on all fluid losses so that the balance canbe carefully regulated.The chief lesson seems to be that effective treatment,

derived from sound physiological principles, can be givenwithout recourse to expensive, and often unobtainable,biochemical assistance.

5. Campbell, K. Ibid, p. 201.6. Aidin, R., Corner, B., Tovey, G. Lancet, 1950, i, 1153.7. Govan, A. D. T., Scott, J. M. Ibid, 1953, i, 607.8. Williams, H. Med. J. Aust. 1953, ii, 203.9. Medical Research Council memorandum no. 36. The Treatment

of Acute Dehydration in Infancy. H.M. Stationery Office, 1912.10. Randall, H. T., Habif, D. V., Lockwood, J. S., Werner, S. C.

Surgery, 1949, 26, 341.11. Stuckey, E. S. Med. J. Aust. 1953, ii, 205.