TERMINOLOGY OF ACID-BASE BALANCE

641 tion for others,

bacteriological

cure

is the

important criterion,

especially in poorer countries. Department of Pharmacology, Faculty of Medicine, Kynsey Road, Colombo, 8.

S. W. BIBILE.

AN AUTOMATIC BREAST PUMP

SIR,-Iwas very interested in the letters by Dr. Huntingford (Jan. 6) and Professor Pinkerton (Feb. 10), and I should like to report our experience with Egnell’s automatic breast pump. About 2800 have been in a

daily trouble-free use in

Sweden

on

large scale for the past few years. It is interesting that mastitis

has decreased during the past ten years in Sweden. This is perhaps because the pump is used in an increasing number of patients who require artificial emptying of the breasts. The pump eliminates the discomfort associated with manual expression (in which pressure on the breast cannot be controlled). The pump was also efficient in restoring inverted nipples to

normal. A minor disadvantage is the use of glass in the nipple shield, because it may break. This disadvantage is outweighed, however, by the advantage that glass is easily sterilised. Moreover, Egnell believes that it is important psychologically for the mothers to see the milk flow. Unfortunately no other transparent material is available which is suitable for repeated sterilisation. Other types of nipple shield, such as metal shields, have been tried but the mothers did not like them. Experiments are in progress to produce nipple shields of a more durable material. Karolinska Sjukhuset,

Department of Obstetrics and Gynæcology, Stockholm, Sweden.

ULF BORELL.

INSULIN-SECRETING CAPACITY IN NEWBORN INFANTS OF NORMAL AND DIABETIC WOMEN SIR,-The paper by Dr. Baird and Dr. Farquhar (Jan. 13) prompts us to report our own findings to support their observations in the normal newborn infant. Using the same technique of rapid intravenous injection of

glucose (1

g. per

kg. body-weight given

as

25% solution)

we

have found a diminished glucose tolerance in normal newborns vaginally delivered. The tests were performed 3-5 hours after delivery. The fasting blood-sugars (F.B.s.) (Somogyi-Nelson) ranged from 28 mg. to 96 mg. per 100 ml. The " increment index" constant (K) varied from 0-72 to 3-45% per min. (mean =1-81% per min.) in the normal newborns studied. The value exceeded 2-65% per min. in only 1 infant. In 5 of these infants the intravenous glucose-tolerance test was repeated at the age of 3 days, when the F.B.S. was 50-80 mg. per 100 ml. The constant (K) at this time was within the normal range (normal male adult, non-diabetic) in two of these infants, being 3’01 and 3-55% per min. In the others it had improved, but was still diminished (1-30, 1-66, 1-75% per min.). Similar results were obtained whether the glucose was administered via the umbilical vein or a peripheral vein. These observations were prompted by a critical reappraisal of intravenous glucose-tolerance tests in the newborn reported by others1 and our earlier studies2 of glucose metabolism in the normal vaginally delivered infant. The latter studies indicated that (1) the disappearance of intravenous galactose was delayed, (2) the response to intravenous glucagon was diminished, and (3) the elevation of blood-sugar after glucagon was prolonged. Desmonddemonstrated a similar phenomenon after administration of adrenaline, and Cornblath’s observations4 were similar to our own for glucagon. 1. 2. 3. 4.

Read, C. H. Amer. J. Obst. Gynec. 1951, 61A, 392. Mulligan, P. B., Schwartz, R. Amer. J. Dis. Child. 102, 490. Desmond, M. M. J. Pediat. 1953, 43, 253. Comblath, M., Levin, E. Y., Marquetti, E. Pediatrics, 1958, 21, 885.

These results suggest that the hypoglycaemia of the newborn is not due to hyperinsulinism. The delayed glucose disappearance from the blood of normal infants may be due to hyperadrenocorticism (i.e., elevated bloodhydroxycorticoids as a result of vaginal delivery) ; however, the low fasting blood-glucose levels are inconsistent with this hypothesis. Further studies are necessary to elucidate the factors which operate in carbohydrate metabolism and control blood-glucose concentration in the normal newborn infant. ROBERT SCHWARTZ

Department of Pediatrics, University Medical School MALCOLM D. BOWIE at Cleveland Metropolitan General Hospital, PAULA B. MULLIGAN. Cleveland, Ohio. Western Reserve

TERMINOLOGY OF ACID-BASE BALANCE

SIR,-The University College Hospital working-party (Feb. 24, p. 419) should be congratulated on its effort to clarify the nomenclature of acid-base balance (ionic equilibrium). To the undergraduate it is a jungle of confusing jargon: a maze of incoherent ideas. The teacher suffers even greater difficulties; for he knows that his terminology will probably only confuse the student. I should like

to

suggest

a

few amendments

to

the pro-

posed schedule. These are based mainly on the concepts 1-5 stressed by Astrup. (A) There are three basic parameters which express the overall ionic picture and which reflect both the respiratory and non-respiratory components: (1) The Peoz Its value in practice is widely accepted since it is an index of alveolar ventilation. By itself it does not indicate whether or not the primary disturbance is respiratory or non-respiratory. (The Astrup micromethod provides a simple reliable method of estimating arterial PC02 without arterial puncture. The technique takes 5 minutes and requires only fingerprick capillary blood). (2) pH This is of fundamental importance. It is a resultant of both the respiratory and the non-respiratory components. The homoeostatic mechanisms of the body are so adaptable that apart from acute, or overwhelming, upsets the pH tends to return to normal. (The difference in meaning of the prefix p in Pcoz and pH should be emphasised.) (3) Base Excess or Deficit This is a valuable term that should be introduced. It reflects the overall " non-respiratory " component of the disturbance. (Definition: excess base gives directly in mEq. per litre the excess of base present in the blood.) All terms containing the word bicarbonate can be avoided, since they do not contribute towards an understanding of the defect in a particular patient (i.e., alkali reserve, COz-combining power, total CO, content, or even standard bicarbonate). The standard bicarbonate is a function of the base excess or deficit.

(B) The term " compensation " should not be disregarded. " Secondary changes " can vary in extent and degree. Acute respiratory failure may be used as an illustration. Initially there is a rise in the arterial Pco,; pH falls (because there is now an excess of hydrogen ions), but since no secondary non-respiratory changes have occurred, there is neither base excess nor deficit (this should be called " uncompensated "). Gradually hydrogen ions are excreted by the kidney in order to return the pH to normal. A base excess is now present, but 1.

Astrup, P., Jorgenson, K., Siggaard Andersen, O., Engel, K. Lancet, 1960, i, 1035. Astrup, P. Scand. J. clin. Lab. Invest. 1956, 8, 33. Siggaard Andersen, O., Engel, K., Jorgenson, K., Astrup, P. ibid. 1960, 12, 172. 4. Siggaard Andersen, O., Engel, K. ibid. p. 177. 5. Singer, R. B., Hastings, A. B. Medicine, 1948, 27, 223. 2. 3.

642 since it is inadequate to compensate for the elevated Pcoa, the pH is still below normal. At first the patient is partially compensated. When the pH returns to normal, the patient is fully compensated. Should he improve rapidly the Pcoa returns to normal, but since there is a base excess, the pH now becomes too high-i.e., the patient has " over-compensated ". (Note that the term " plasma-bicarbonate " has not been used.)

A similar concept can be used in non-respiratory disturbances. Since the nomenclature suggested by the U.C.H. group will probably become standard usage, I should like to suggest that these two concepts are included and that the term total CO2 is discarded. Two further thoughts deserve emphasis. For obvious reasons a study of acid-base balance cannot be complete without reference to hydrogen-ion excretion by the kidney. Moreover, at present, we are entirely ignorant of intracellular acid-base balance. A plea has been made for even more simplicity of terminology and methodology. The method described requires only one biochemical estimation, rather than three separate procedures as suggested by the U.C.H. group. This has the virtue of simplifying the biochemists’ task. Queen Elizabeth Hospital, Edgbaston, Birmingham, 15.

M. S. GOTSMAN.

FEMORAL HERNIA

SIR,-How extraordinary that The Lancet can devote a long leading article to the subject of femoral hernia and lay such little stress on the two facts which have most to do with its mortality. Inexcusably the diagnosis is often made too late or not at all. Will your scholarly exercise influence anyone in the direction of earlier diagnosis and operation, or will it provoke more academic discussion ?

Again, non-operative treatment is so dangerous as to find no place in good medicine. Trusses for femoral hernia are useless and dangerous, and yet advertisements for them have appeared in reputable medical journals. Moreover, femoral trusses were still listed in an official Ministry circular1 on appliances, published in 1961. Edgbaston, Birmingham.

FAUSET WELSH.

SPELLBINDING AND SPELLBREAKING IN CONVALESCENCE SIR,-Dr. Day’s description of rehabilitation (Jan. 27) reminds me of the first patient who had a transorbital

leucotomy operation by a hospital in Ranchi, India.

new

technique in

a

mental

The operation was done in the morning, and the same afternoon I went out to watch the finish of an exciting game of soccer, in which the hospital team beat a visiting team. After the match I was congratulating our players, and, to my horror, I found the patient among them. He said he felt all right, and indeed he was, except for the usual black eyes which were not very obvious. It turned out that our P.T. instructor had his name on the list to play that day, but was not informed about the operation; the patient himself, as often happens, was unaware that he had had any operation, and walked out to the football field as usual. Most of the wards in that hospital had been unlocked since it was opened in 1919. The late Lieut.-Colonel Barkeley Hill, who was medical superintendent almost from the beginning, was responsible for this. He was a man who lived before his time. Ranchi, Bihar,

R. B. DAVIS. India.

1. Standard List of

Appliances. Ministry of Health, July, 1961, p. 24.

THE RISK OF AN OPERATION

SIR,-I read with much interest the letter by Mr. Skyrme Rees (March 17) and note that 6 of the 7 deaths due to pulmonary embolism. The late Prof. Lambert Rogers, of Cardiff, emphasised many years ago that a pulmonary embolus followed thrombosis of a posterior tibial vein or one of its tributaries. This was encouraged by compression of these veins if the legs were allowed to rest on the table, and, the longer the operation, the greater the risk. He insisted that the heels must be elevated-e.g., by resting on a sandbag -in every case in which pulmonary embolism might occur. Since following his advice, in spite of much surgery on patients in an age-group and with conditions which favour embolism, I have had only 1 fatal case. This was a woman aged 39 years, who was thought to have a trivial condition, so the sandbag was omitted. It was discovered, under the anaesthetic, that she had a carcinoma of the colon, so the operation was much longer than anticipated, and nobody thought of elevating the heels. She suddenly succumbed to a pulmonary embolus on the fifth day. 6 cases of pulmonary embolus in a comparatively young age-group, and for an operation which usually takes only a few minutes, seems tragic. I wonder whether their heels were raised from the table ? As the mortality has remained constant since 1934-i.e., before the importance of supporting the heels was recognised-I rather doubt it. MCNEILL McNEILL LOVE. LovE. London, W. 1. were

PARENTS OF MENTALLY HANDICAPPED CHILDREN SIR,-Ihave been interested in the views of parents of

mentally handicapped children. They have accorded with my own experience in the clinical situation, and I would wholeheartedly agree with explaining the nature of the handicap to parents at the earliest opportunity. It has been my practice for the past ten or twelve years to inform the parents of mongols within twenty-four hours of the child’s birth, should it be delivered in hospital under my care, and immediately on first interview where this does not take place at birth. It is clear that the mother immediately after delivery is not always in a fit condition to accept such information and usually does not understand the explanation in the same terms as her husband does. Nevertheless, I have had sufficient evidence of the gratitude of parents when this course has been followed to make it my policy to continue in this way. Dr. Joyce Leeson,! who recently studied the adjustment of families to their mentally handicapped children, observed that adjustment was better in those families informed early of the child’s handicap and less satisfactory when the information had been withheld for a time. The position is not nearly so simple with other forms of mental handicap, where the diagnosis may evolve over a period of weeks or even months. Here, it seems important to have continuity of advice by those responsible for the child, either the general practitioner or the hospital paediatrician. Only by honest discussion of the baby’s state from time to time can confidence be built up, so that one is in a position to give adequate explanation to the parents when the diagnosis has become clear. The skill with which one does this depends, of course, on ability to handle anxious parents in a worrying and difficult situation. It is, however, usually more difficult for all parties when gratuitous advice is inserted on casual examination by some other observer. This policy naturally involves the regular review of all infants born in a maternity hospital or in a practitioner’s practice who may be regarded as " at risk ". I hope we would not regard it as the duty of an almoner to tell 1. Med.

Offr., 1960, 104,

311.