Claes Thorén

Limb circulation in anorexia nervosa.

ABSTRACT. Blood flow, skin temperature and blood pressure of the lower limbs and the effect of indirect, radiant heat on calf blood flow and leg skin temperature was determined in sixteen children with anorexia nervosa (group A) and fourteen healthy children (group H) of the same age and body height. Calf blood flow was measured by venous occlusion plethysmography. Arm blood pressure was obtained by tourniquet and toe pressure and digital plethys‐mograms by a strain‐gauge. Skin temperature was measured with a thermocouple. In group A calf blood flow was about 50–60 % lower than the mean values observed in group H and a marked difference was maintained after the heat load. Skin temperature of the knees and toes were higher in group H. Systolic arm blood pressure and toe pressure were on the average 20 mmHg and 13 mmHg lower in group A. It is suggested that there is a heat‐conserving, selective peripheral vasoconstriction in the anorexic patients.

Renal function in Fallot's tetralogy.

Abstract. Aperia, A., Bjarke, B., Broberger, O. and Thorén, C. (Department of Paediatrics, Karolinska Institutet, S:t Görans Childrens Hospital, Stockholm, Sweden). Renal Function in Fallots Tetralogy. Acta Paediatr Scand, 63: 398, 1974.–Renal function was examined in 11 adults with Fallots tetralogy. The following aspects of renal function were studied: GFR, PAH clearance, filtration fractions, the natriuretic response to an oral salt load and renal regulation of acid base balance. The GFR was found to be only moderately reduced while PAH clearance showed an almost 50% reduction in most cases studied. Consequently the filtration fraction was abnormally high. The natriuretic response to an oral salt load was generally low. The urinary sodium elimination rate was found to he independent of deviations in GFR and correlated inversely with the filtration fraction. The renal response to ammonium chloride induced acidosis WBS studied in 7 patients and was delayed in at least 3 of those. The pathological response was thought to he due to hypocapnic depression of renal HCO3 reabsorption. It is suggested that this could contribute to the mild nonlactic acidosis onen present in congenital cyanotic heart disease.

Prolonged exercise in adolescent boys with juvenile diabetes mellitus. Circulatory and metabolic responses in relation to perceived exertion.

Abstract. Persson, B. and Thorén, C. (Department of Pediatrics, Karolinska Institutet, St. Görans Childrens Hospital, Stockholm, Sweden). Prolonged exercise in adolescent boys with juvenile diabetes mellitus. Circulatory and metabolic response in relation to perceived exertion. Acta Paediatr Scand, Suppl. 283: 62, 1980.—Seven well‐trained adolescent boys with juvenile diabetes mellitus were studied. They were non‐ketotic and performed a 60 min exercise in the afternoon at an average intensity of 58 % of maximal working capacity. Blood glucose, blood lactate, plasma levels of insulin, C‐peptide and 3‐hydroxybutyrate, oxygen uptake and respiratory quotient were determined. The perception of exertion was scored as rate of perceived exertion. Healthy athletes of the same age were controls. Blood glucose, monitored continuously, decreased successively after 10–15 min of exercise with a significant correlation to the pre‐exercise glucose value. Blood glucose decreased during exercise to the same level or below that of controls. Despite hypoglycemia with values of 2–3 mmol/l, the exercise continued. Plasma insulin was unchanged. The 3‐hydroxybutyrate level was significantly higher in the diabetics, increased somewhat during exercise and still more during the recovery period. The diabetic subjects had significantly higher systolic blood pressure and heart rate during exercise despite a relatively equal work intensity and lower absolute workload. The rate of perceived exertion increased normally during exercise without interference of decreasing blood glucose.

EFFECT OF METABOLIC CONTROL AND DURATION ON EXERCISE - INDUCED ALBUMINURIA IN DIABETIC TEEN-AGERS

ABSTRACT. Nineteen type I diabetic teen‐agers without clinical signs of nephropathy with a duration of diabetes varying from 3 to 16.8 years were examined by a standardized exercise test for analysis of urinary excretion of albumin and β2‐microglobulin. The patients were studied both in poor and improved (but not perfect), metabolic control as defined by HbA1 and blood glucose profiles, and the values were compared to those of 14 age‐matched healthy controls. The controls showed no increase in albumin excretion rate during excercise as was found in diabetic patients. The albumin excretion rate during exercise was significantly correlated (p<0.05) to systolic blood pressure in the diabetic patients. Blood pressure in the diabetic patients was, however, similar to that of controls both at rest and during exercise. Urinary β2‐microglobulin did not change during exercise. The urinary albumin excretion during exercise decreased significantly with improved metabolic control in diabetic patients, but the albumin excretion rate was not correlated with either blood or urinary glucose or diuresis during the exercise test. When metabolic control was unproved there was a significant correlation between the increase in albumin excretion rate during exercise and the duration of diabetes, indicating that part of the exercise‐induced albumin excretion might reflect irreversible morphological changes in the diabetic kidney. This test might therefore have a predictive value for diabetic nephropathy if performed during strict metabolic control.

Repair of Complete Atrioventricular Canal: 15 Years' Experience

Corrective surgery for complete atrioventricular canal was performed over a 15-year period on 72 patients, 49 of whom had Downs syndrome: 46 were without major associated cardiac anomalies and 15 had previously undergone pulmonary artery banding. The pressures in the right and left ventricles equilibrated in 77% of the patients. The early mortality rate was 18% and the late mortality 7%. At follow-up 4% of the patients had severe mitral incompetence and 6% had severe tricuspid incompetence. The mean reduction of pulmonary artery pressure was 40 mmHg. The mean peak systolic pressure ratio between pulmonary artery and aorta was 0.73 before repair and had fallen to 0.38 at follow-up catheterization, when 88% of the patients were asymptomatic. Early repair in the first year of life is nowadays preferred in order to avoid progressive pulmonary vascular disease. Although the alternative of first-stage pulmonary artery banding gave lower (13%) mortality at the corrective operation, it cannot be recommended if atrioventricular valvular incompetence is significant.

Exercise testing with special reference to children with diabetes mellitus.

Abstract. Thorén, C. (Department of Pediatrics, St. Görans Childrens Hospital, Stockholm, Sweden). Exercise testing with special reference to children with diabetes mellitus. Acta Paediatr Sand, Suppl. 283: 29, 1980.—The purpose of exercise testing in diabetes mellitus is to examine physical fitness and to motivate the patient to perform physical activity as a valuable part of the treatment. Different types of tests and ergometry are presented. The step wise increase of workload at submaximal levels is recommended for diabetics as an annual test. Maximal exercise is of value in determining the maximal oxygen uptake (v˙o2 max)=the aerobic capacity, maximal heart rate and systolic blood pressure.

THE RENAL RESPONSE TO AN ORAL SALT AND FLUID LOAD IN CHILDREN WITH COARCTATION OF THE AORTA

The natriuretic effect of an oral salt load has been tested in 6 children before and after resection of coarctation of the aorta. Pre‐ and postoperative determinations of GFR and PAH clearances were also made. Preoperatively the natriuresis following the salt load was depressed, indicating enhanced tubular sodium reabsorption. The GFR was slightly elevated, the PAH clearance was normal and the filtration fraction was elevated. Postoperatively there was an increase in the natriuretic response and a fall in the filtration fraction. There was a significant inverse correlation between the filtration fraction and the urinary excretion of the salt load. The results suggest that coarctation of the aorta is associated with a shift in intrarenal vascular resistance and that this hemodynamic change will, by rise in the oncotic pressure of the peritubular capillaries, result in the enhancement of the tubular sodium reabsorption.