Br. J. Surg. Vol. 66 (1979) 412-414
The excretion of alkaline ribonuclease by children undergoing surgery G. B. BARLOW, S U S A N H. W H I T E A R A N D A. W. W I L K I N S O N * SUMMARY
Tlie excretion of alkaline ribonuclease has been measured in the urine of two groups o j children after major oper-ations. The excretion was significantly increased in all patients after open operations on the heart and in many ofthose who were operated on soon after birth for anomalies in the intestine. It is suggested that these eleuations may indicate a disturbance of pancreatic jirnction. IN adults severe pancreatitis has been observed after some kinds of cardiac operation. The condition has been attributed to the disturbance of the blood supply and is most common in patients who die (Feiner, 1976). Elevation of the concentrations of amylase in serum and of urine of up to ten times the normal level are taken as indications of pancreatitis and, following recovery, the amylase concentrations in both serum and urine rapidly return to within the normal range. Similar large increases in the serum amylase concentration may be observed during the first 2 days after operations on the chest and a moderate elevation may persist for several further days (Hennings and Jacobson, 1974). It has been shown that three degrees of malnutrition in children can be recognized according to the concentrations of ribonuclease in the urine and serum (Sigulem et a]., 1973). We have shown recently that the urinary output of ribonuclease may be greatly increased in children after injury by burning or scalding (Barlow and Whitear, 1977). We have, therefore, examined the urinary output of ribonuclease in two groups of children, one group having had open operations on the heart and the other, operative treatment soon after birth for various intestinal abnormalities.
Patients and methods Urine was obtained from 6-hourly specimens collected postoperatively from 31 children for u p to 16 days as part of a series of metabolic balance studies. The urine was collected into ion-free plastic bags (Hollister) and deep frozen without preservative until required for assay; urine can be stored frozen for up to 12 months without any efiect on the enzyme activity. Control urine values were obtained from measurements in 13 children aged 10 months to 10 years who had been admitted to hospital for minor operations and from 3 normal neonates (21 occasions) and from 2 neonates with Beckwith’s syndrome (4 occasions). Details of the patients, diagnoses and operations are shown in Tnble I. The urinary alkaline ribonuclease activity was measured as described by Barlow and Whitear (1977).
Results The output of ribonuclease in the 13 control children aged 10 months to 10 years was 0.43k0.29 Kunitz units 24 h-1 kg-1 (mean k s.d.), and in 25 single 24-h collections from neonates was 0.52 k 0.2 Kunitz units 24 h-1 kg-1 (mean k s.d.). The method had a coefficient of variation of 13.9 per cent. After open heart operations excretion of ribonuclease in the urine was significantly raised for about
Table I: DETAILS OF THE CASE SERIES Case no. Age Diagnosis and operation 1 4 mth Ventricular septal defect; patent foramen ovale 2 4d Total anomalous pulmonary venous drainage 3 7 yr Ventricular septal defect 4 23 d Pulmonary stenosis 5 7 mth Transposition of the great arteries; ventricular septal defect; patent ductus arterosis 6 6 mth Transposition of the great arteries 7 9 mth Transposition of the great arteries 8 5 mth Transposition of the great arteries Total anomalous pulmonary venous 9 14 d drainage; patent ductus arterosis; atrial septal defect Ventricular septal defect; aortic stenosis 10 1 mth Total anomalous pulmonary venous drainage 11 14 d Oesophageal atresia and tracheo-oesophageal 12 7d fistula Oesophageal atresia and tracheo-oesophageal 13 3d fistula Tracheo-oesophageal fistula 14 2d Gastroschisis 15 2d Gastroschisis 16 14 d Gastroschisis 17 3d Gastroschisis 18 2d Hirschsprung’s disease 19 2d 20 Hirschsprung’s disease 6 wk 21 Laparotomy : right cutaneous ureterostomy 1 mth 22 10 mth Laparotomy : colostomy 23 Laparotomy : necrotizing enterocolitis 7d 24 Intestinal obstruction 5d 25 Intestinal obstruction 1 mth 26 Ileal atresia 8d 27 Ileal atresia; small bowel volvulus 2d 28 10 wk ‘Apple-peel’ small bowel; multiple jejunal atresias 29 Multiple small bowel adhesions 4 mth 30 Enteric duplication 6 mth 31 Ladd’s bands; malrotation of the mid-gut 6d
8 days and in some patients for even longer (Table I I ) . The urinary excretion of ribonuclease, averaged over the period for which collections were made, was also increased in 14 out of 20 patients operated on soon after birth for intestinal anomalies. Even in 3 of those cases that did not show an overall increase there were several days when significantly high levels were observed. There was no correlation between urine volume and the excretion of the ribonuclease. Gaps in Tables II and I l I indicate that the ribonuclease activity was not measured on these days either because there were no urine collections made or because the collections were incomplete. The output of amylase was below the detectable limit (10 Somogyi units/day) in all controls and was detected at very low levels, far below the normal adult range, only on the first day in 4 patients after *Institute of Child Health, 30 Guilford Street, London WClN IEH.
Excretion of alkaline ribonuclease in children Table 11: URINARY ALKALINE RIBONUCLEASE ACTIVITY AFTER CARDIAC SURGERY (Kunitz units 24 h-' kg-') Day after opsration Case no. 1 2 3 4 5 6 7 8 9 1 2 3 4 5 6 7
2.7 1.9 1.4 2.9 2.2 4.1 0.2 0.2 4.7 1.8 2.1
8
9 10 11
3.4 2.5 1.3 2.2 1.o 3.2 1.2 2.2 1.4 2.7 3.5
4.3 4.4 3.0 2.9 1.o 3.9
2.9 3.6 3.6 60 1.3 3.8 1.4 0.4 6.8 41 3.7
1.5
2.3 5.1 3.8 3.6
2.2 2.6 1.8 5.0 2.8 5.0 1.1 2.0 6.1 5.1 4.8
1.2 3.7 1.3 3.4 0.8 2.5 0.7 2.5 6.7 3.9 5.4
1.0
2.2 1.2 0.8 2.3 1.3 0.8 0.9 3.7 2.2 3.2
413
10
P
2.3
1.7
to-01
The excretion of alkaline ribonuclease by children undergoing surgery G. B. BARLOW, S U S A N H. W H I T E A R A N D A. W. W I L K I N S O N * SUMMARY
Tlie excretion of alkaline ribonuclease has been measured in the urine of two groups o j children after major oper-ations. The excretion was significantly increased in all patients after open operations on the heart and in many ofthose who were operated on soon after birth for anomalies in the intestine. It is suggested that these eleuations may indicate a disturbance of pancreatic jirnction. IN adults severe pancreatitis has been observed after some kinds of cardiac operation. The condition has been attributed to the disturbance of the blood supply and is most common in patients who die (Feiner, 1976). Elevation of the concentrations of amylase in serum and of urine of up to ten times the normal level are taken as indications of pancreatitis and, following recovery, the amylase concentrations in both serum and urine rapidly return to within the normal range. Similar large increases in the serum amylase concentration may be observed during the first 2 days after operations on the chest and a moderate elevation may persist for several further days (Hennings and Jacobson, 1974). It has been shown that three degrees of malnutrition in children can be recognized according to the concentrations of ribonuclease in the urine and serum (Sigulem et a]., 1973). We have shown recently that the urinary output of ribonuclease may be greatly increased in children after injury by burning or scalding (Barlow and Whitear, 1977). We have, therefore, examined the urinary output of ribonuclease in two groups of children, one group having had open operations on the heart and the other, operative treatment soon after birth for various intestinal abnormalities.
Patients and methods Urine was obtained from 6-hourly specimens collected postoperatively from 31 children for u p to 16 days as part of a series of metabolic balance studies. The urine was collected into ion-free plastic bags (Hollister) and deep frozen without preservative until required for assay; urine can be stored frozen for up to 12 months without any efiect on the enzyme activity. Control urine values were obtained from measurements in 13 children aged 10 months to 10 years who had been admitted to hospital for minor operations and from 3 normal neonates (21 occasions) and from 2 neonates with Beckwith’s syndrome (4 occasions). Details of the patients, diagnoses and operations are shown in Tnble I. The urinary alkaline ribonuclease activity was measured as described by Barlow and Whitear (1977).
Results The output of ribonuclease in the 13 control children aged 10 months to 10 years was 0.43k0.29 Kunitz units 24 h-1 kg-1 (mean k s.d.), and in 25 single 24-h collections from neonates was 0.52 k 0.2 Kunitz units 24 h-1 kg-1 (mean k s.d.). The method had a coefficient of variation of 13.9 per cent. After open heart operations excretion of ribonuclease in the urine was significantly raised for about
Table I: DETAILS OF THE CASE SERIES Case no. Age Diagnosis and operation 1 4 mth Ventricular septal defect; patent foramen ovale 2 4d Total anomalous pulmonary venous drainage 3 7 yr Ventricular septal defect 4 23 d Pulmonary stenosis 5 7 mth Transposition of the great arteries; ventricular septal defect; patent ductus arterosis 6 6 mth Transposition of the great arteries 7 9 mth Transposition of the great arteries 8 5 mth Transposition of the great arteries Total anomalous pulmonary venous 9 14 d drainage; patent ductus arterosis; atrial septal defect Ventricular septal defect; aortic stenosis 10 1 mth Total anomalous pulmonary venous drainage 11 14 d Oesophageal atresia and tracheo-oesophageal 12 7d fistula Oesophageal atresia and tracheo-oesophageal 13 3d fistula Tracheo-oesophageal fistula 14 2d Gastroschisis 15 2d Gastroschisis 16 14 d Gastroschisis 17 3d Gastroschisis 18 2d Hirschsprung’s disease 19 2d 20 Hirschsprung’s disease 6 wk 21 Laparotomy : right cutaneous ureterostomy 1 mth 22 10 mth Laparotomy : colostomy 23 Laparotomy : necrotizing enterocolitis 7d 24 Intestinal obstruction 5d 25 Intestinal obstruction 1 mth 26 Ileal atresia 8d 27 Ileal atresia; small bowel volvulus 2d 28 10 wk ‘Apple-peel’ small bowel; multiple jejunal atresias 29 Multiple small bowel adhesions 4 mth 30 Enteric duplication 6 mth 31 Ladd’s bands; malrotation of the mid-gut 6d
8 days and in some patients for even longer (Table I I ) . The urinary excretion of ribonuclease, averaged over the period for which collections were made, was also increased in 14 out of 20 patients operated on soon after birth for intestinal anomalies. Even in 3 of those cases that did not show an overall increase there were several days when significantly high levels were observed. There was no correlation between urine volume and the excretion of the ribonuclease. Gaps in Tables II and I l I indicate that the ribonuclease activity was not measured on these days either because there were no urine collections made or because the collections were incomplete. The output of amylase was below the detectable limit (10 Somogyi units/day) in all controls and was detected at very low levels, far below the normal adult range, only on the first day in 4 patients after *Institute of Child Health, 30 Guilford Street, London WClN IEH.
Excretion of alkaline ribonuclease in children Table 11: URINARY ALKALINE RIBONUCLEASE ACTIVITY AFTER CARDIAC SURGERY (Kunitz units 24 h-' kg-') Day after opsration Case no. 1 2 3 4 5 6 7 8 9 1 2 3 4 5 6 7
2.7 1.9 1.4 2.9 2.2 4.1 0.2 0.2 4.7 1.8 2.1
8
9 10 11
3.4 2.5 1.3 2.2 1.o 3.2 1.2 2.2 1.4 2.7 3.5
4.3 4.4 3.0 2.9 1.o 3.9
2.9 3.6 3.6 60 1.3 3.8 1.4 0.4 6.8 41 3.7
1.5
2.3 5.1 3.8 3.6
2.2 2.6 1.8 5.0 2.8 5.0 1.1 2.0 6.1 5.1 4.8
1.2 3.7 1.3 3.4 0.8 2.5 0.7 2.5 6.7 3.9 5.4
1.0
2.2 1.2 0.8 2.3 1.3 0.8 0.9 3.7 2.2 3.2
413
10
P
2.3
1.7
to-01
