583 Postgrad Med J: first published as 10.1136/pgmj.34.397.583 on 1 November 1958. Downloaded from THE MODERN TREATMENT OF ANURIA AND OLIGURIA By DAVID K. BROOKS, M.B., B.S. Research Fellow Surgical Unit, St. Mary's Hospital, London, W.z2 There are few conditions which offer a greater operative procedures; bilateral renal calculi; challenge to the medical and nursing staff than carcinoma of the prostate and cervix; procidentia, that of acute renal failure. There are also few etc. conditions where the application of modern tech- (b) Dehydration and electrolyte depletion, e.g. niques and careful clinical biochemical assess- low salt syndrome. ment are more essential to the achievement of (c) Tubular necrosis such as follows: gross success. dehydration; prolonged hypertension; separation True or complete anuria rarely occurs except of placenta; abortion; crush syndrome; miss- where there is mechanical obstruction and, as matched blood transfusion; nephrotoxins, e.g. early recognition of oliguria is essential in acute mercuric chlorides, bismuth, sulphonamides. renal failure, it is important to define it in a (d) Acute nephritis. Protected by copyright. recognizable form. The history of a successfully treated case of The normal output of urine varies between one acute suppression of urine normally falls into four and two litres per day. On a mixed diet it is phases: obligatory to pass a minimum volume of approxi- (a) The precipitating condition or cause. mately 500 ml. in 24 hours (Gamble, I947). This (b) The anuric phase. entails good renal function and the ability to con- (c) The diuretic or pre-recovery phase. centrate fully to a maximum specific gravity of (d) The recovery phase. I.o35 (I,I55 m. osm./l.). Oliguria has been defined as less than 700 ml. in The Precipitating Condition or Cause 24 hours. Where good renal function is present Careful clinical assessment to elucidate the such urine will concentrate sufficiently to produce causation of anuria is important because of the a specific gravity of i.oi8 (595 m. osm./l.) or more. undesirability of prolonging an irreversible condi- Where renal damage is present, a low specific tion, and the need of remedying quickly, and to gravity of i.oo8 (265 m. osm./l.) to 1.o014 (460 m. the maximum, any condition that is immediately http://pmj.bmj.com/ osm./l.) is to be expected (Joekes, I957). Severe treatable. oliguria may be defined as a urine output of Dehydration, electrolyte imbalance, low blood 500 ml. or less in 24 hours. pressure are all easily treatable. Sulphonamide Where there is a urine output of 300 ml. or less, anuria usually responds to alkalis and increased such will be the inability of the kidneys to keep fluids. pace with the production of metabolites, the The onset of renal failure, following poisoning condition might well be called metabolic anuria. with bismuth or mercuric chloride, may be avoided The object of therapy in oliguria and anuria is by the early use of British anti-lewisite or calcium on September 28, 2021 by guest. to tide the patient over until the kidneys have time disodium versenate. These substances may be to recover their function. toxic, however, once anuria is established (Stock, At this time, it is probably true to say that 1952; Merrill, 1955). suppression of urine due to malignant hyperten- Care must be observed in the treatment of de- sion, chronic nephritis and polycystic kidneys hydration and electrolyte imbalance in case renal developing into oliguria, and the rare condition of damage has already occurred. bilateral cortical necrosis, is, in the main, not reversible. The Anuric Phase The reversible causes of acute renal suppression Three factors emerge as a consequence of the may be listed as: acute suppression of urine: (a) Mechanical-obstruction of the ureters, by: (a) The retention of water. 584 POSTGRADUATE MEDICAL JOURNAL November 1958Postgrad Med J: first published as 10.1136/pgmj.34.397.583 on 1 November 1958. Downloaded from (b) The accumulation of the products of meta- this is clinically possible, is by no means contra- bolism, urea, uric ,acid, creatinine, phosphate, indicated. sulphate, etc. An accurate record of all additions to the patient (c) The metabolic upsets arising from the above, in the form of fluids, such as medicines, ion as yet little understood, but involving the shift of exchange resin, etc., and all losses in the form of electrolytes from the cells to the extra-cellular vomit, urine and faeces must be kept, in order for fluid compartments, and for want of a better term this assessment to be made. may be called the poisoned-cell phenomenon. The measured insensible loss of the average The consequences of fluid retention rapidly be- adult is now accepted to be less than one litre in come apparent when unrestricted fluid intake is 24 hours and generally falls as the time from the allowed, or worse, when fluids are forced in the onset of anuria progresses, probably because of misguided attempt to invoke a diuresis. In either endogenous production of water from fat meta- case, cardiac failure, oedema, pulmonary conges- bolism (Swan and Merrill, I953). tion, hypertension, cerebral oedema and the symp- With this in view, and the probability that some toms of water intoxication will result. degree of overhydration may have occurred by the time the oliguric state has been recognized, as The most common cause of death within I4 little as 400 ml. in 24 hours can be recommended days of the onset of oliguria due to renal disease in the early stages of treatment, and a graaual loss is overhydration (Bull, Joekes and Lowe, I949). of weight, as food stores are used up, is to be Even when overhydration is not a factor, the re- desired (Merrill, I955). tained products of metabolism produce the gradual The accurate measurement of urine output is of onset of lethargy, coma, vomiting, pericarditis and paramount importance, not only for the assess- lowered resistance to infection. The rising con- ment of fluid replacement, but for the determina- centration of potassium in the body is reflected in tion of the progress of the patient, and the amount high plasma-potassium levels and is associated of urea and electrolytes excreted. Protected by copyright. with cardiac failure and muscle weakness. If necessary, therefore, a When the kidney begins to recover it secretes a self-retaining catheter dilute urine of low concentration, which, on reach- should be inserted into the bladder and, after ing a volume of a litre or more, begins to reduce emptying, a measured quantity of fluid, containing the blood urea. an antibiotic, passed back into the bladder through the catheter: 30 ml. of fluid containing ioo mg. of The kidney at this stage still has an impaired chloramphenical has been used successfully. This tubular function, unable to concentrate and to volume is deducted from the volume of urine differentiate between electrolytes. Thus, the pass- obtained on releasing the catheter. ing of a profuse dilute urine may soon lead to In order to avoid the oral complications asso- dehydration, and electrolyte imbalance and de- ciated with oliguria and its treatment, i.e. parotitis, pletion. thrush and ulceration, part of the fluid Within a variable period of time, usually six to intake eight weeks, full return of kidney function is to be should be taken by mouth. This regime should be expected, sometimes with no detectable abnor- reinforced by the sucking of pure glucose sweets, mality (Lowe, 1952; Oliver, 1953). followed by bland antiseptic mouth washes. http://pmj.bmj.com/ The Suppression of Harmful Metabolites The Regulation of Water The main metabolic consequences the anuric The fluid requirements in the anuric patient patient has to face arise from the metabolism of need to be assessed accurately each 24 hours so protein, producing a rising blood non-protein that the building up of a positive or negative im- nitrogen, cardiotoxic levels of plasma potassium, balance is avoided as time progresses. These re- and release of unexcretable fixed acid. quirements amount to the fluid loss through the Therapy is therefore directed towards a com- on September 28, 2021 by guest. skin, lungs, urine, vomit and faeces. pletely protein-free intake and the reduction of Although various formulae are available for the endogenous protein metabolism. Advantage is assessment of insensible loss through the skin and therefore taken of the protein-sparing effect of lungs, none can be applied with confidence to glucose and, owing to the necessity of restricting every patient. fluid intake, this entails the use of hypertonic The simplest and most accurate method is to solutions. Up to 50 per cent. glucose can be safely record the daily change in weight, the weighing injected into a large vein by means of a polythene being performed at the same time each day and on catheter (Bull, 1952). Although the procedure of the same scales, with the bladder empty. Ideally passing the catheter is simple, in the condition of this is done on a bed weighing machine, but anuria, where it may by necessity stay in situ for mobilization of the patient for weighing, where three weeks, maximum precautions for sterility November I958 BROOKS: The Modern Treatment of Anuria and Oliguria 585 Postgrad Med J: first published as 10.1136/pgmj.34.397.583 on 1 November 1958. Downloaded from LLOYD-LUKE Books that enshrine profound thought GENERAL PATHOLOGY INTRODUCTION TO FLUID BALANCE 11tSURGERY IN SURGICAL PRACTICE (2nd Edited by D. H. PATEY (2nd edit.) M.D., F.R.C.P., F.R.S. (1958) Cloth-bound 17s. 6d. net D.M.(Oxon.), F.R.C.S.(Eng.) (1958) 84s. net (1958) Paper-covered 9s.