Eur J Pediatr (1992) 151:377-380
European Journal of
Pediatrics
9 Springer-Verlag1992
Infectious and surgical complications of childhood continuous ambulatory peritoneal dialysis J. P. M. van Asseldonk 1, C.H. Schr6der 1, R. S. V. M. Severijnen 2, M. C. J. W. de Jong 1, and L. A. H. Monnens 1 Departments of 1Paediatrics, 2paediatric Surgery, Sint Radboud University Hospital, P.O. Box 9101, NL-6500 HB Nijmegen, The Netherlands Received May 28, 1991 / Accepted in revised form September 12, 1991
Abstract. A 10-year retrospective study was p e r f o r m e d with respect to the incidence of infectious and surgical complications in a young paediatric continuous ambulatory peritoneal dialysis population of 43 children (mean age 4.5 years [range 2.5 m o n t h s - 1 5 . 8 years]). The incidence of infectious complications such as peritonitis and catheter-related infections correlated well with the results of other studies. A relatively high incidence of hernias (53%) was seen in our population, probably caused by the lower m e a n age of the children. Obstructions were caused by omental wrapping, peritonitis, or operative procedures and did not correlate with the period of catheter function. Early leakage occurred within 5 days after catheter implantation. Later leakages were preceeded by another complication, such as infection or obstruction. In early leakage, in contrast to later leakage, the catheter could be maintained. Key words: Continuous ambulatory peritoneal dialysis Surgical complications - Peritonitis - Hernias - Childhood
Introduction The most c o m m o n complication during childhood continuous ambulatory peritoneal dialysis ( C A P D ) is peritonitis. Catheter-related problems such as exit-site and tunnel infections, obstruction and leakage are also encountered. M o r e o v e r hernias are often seen in childhood C A P D [6]. We p e r f o r m e d a retrospective review of the children admitted to the peritoneal dialysis p r o g r a m m e from 1980 until 1990. A higher incidence of surgical complications was expected in our population, which was considerably younger than that presented in other series.
Patients and methods Between 1980 and 1990 a total of 43 children (27 boys and 16 girls) were admitted to the CAPD programme. The incidence of surgical complications in this population was evaluated. Mean age of the children was 4.5 years (range 2.5 months-15.8 years) at the start of treatment (Fig. 1). Total treatment experience amounted to 858 months, which is a mean patient treatment time of 20 months (range 3.5-60 months). Treatment protocols were largely unchanged throughout the whole period. Under antibiotic prophylaxis with cephazolin and gentamycin a Toronto Western Hospital II catheter was inserted in the operating theatre under general anaesthesia. Immediately after insertion dialysis was started using 20ml dialysis fluid per kg body weight (Dianeal, Baxter, Deerfield, IL, USA). Heparin (500 units/1 dialysis fluid) was added to the diolysis fluid for 3 days. Dialysate was exchanged every 3 h on the first 2 days and every 4 h on the 3rd day. On the 4th day the routine peritoneal dialysis schedule was started (40 ml/kg body weight with four exchanges daily). The Baxter spike system was used throughout the whole period. Since 1987 exchanges were preceeded by sterilizing the spike-connection by UV-irradiation (Baxter UV-XD device). Exit-site care was performed daily by the parents, by careful washing and drying, followed by spraying of the exit-site with chlorhexidine spray. The exit-site then was covered by a single sterile gauze. The incidence of surgical complications was evaluated retrospectively. Peritonitis episodes and catheter-related infections (exit-site as well as tunnel infections) were scored separately, as well as hernias (divided into inguinal and umbilical hernias), early
lO._Dumber of children (N)
8
6
4
2
Offprint requests to: C. H. Schr6der 0
Abbreviation: CAPD = continuous ambulatory peritoneal dia-
lysis
0
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
(years) Fig. 1. Age distribution of the patient population studied age
378 leakages, and obstruction of the catheter. With respect to peritonitis an episode was not considered as a new period if it occurred within 2 weeks after discontinuation of the antibiotic therapy and was caused by the same micro-organism [12].
Results
Peritonitis Eighty-two peritonitis episodes were encountered during the study period (1 episode every 10.5 patient months) of which 23 (28%) were preceeded by a tunnel infection. Eighteen patients (42%) did not suffer from peritonitis during their treatment. Since 1987, after introduction of the UV-XD device, the infection rate decreased considerably. Up to 1987 59 peritonitis episodes were observed in 398 patient months (1 episode every 6.7 months). F r o m 1987 to 1990 23 peritonitis episodes were perceived in 460 patient months (1 episode every 20 months) (Table 1). Causative micro-organisms are summarized in Table 2. Table 1. Peritonitis episodes related to treatment months and time
period
Totalperiod 1980-1986 1987-1990
CAPDmonths
Peritonitis episodes
Frequency
858 398 460
82 59 23
1:10.5 months 1: 6.7 months 1:20 months
Table 2. Causative micro-organisms of peritonitis Number Staphylococcus aureus Staphylococcus epidermidis Streptococcus viridans Pseudomonas Others Sterile
23 12 10 5 18 14
Total
82
% 28.0 14.6 12.2 6.1 21.9 17.1
Total catheter-related infections Exit-site infections Tunnel infections
38 12 26
Catheter-related infections were divided into exit-site infections and tunnel infections. Twelve out of 43 patients (28%) had 12 exit-site infections (mean duration of therapy 27.3 months), pointing to an overall frequency of 1 exit-site infection every 71.5 months. Sixteen out of 43 patients (37%) had one or more tunnel infections (mean duration of therapy 27.2 months). Their 26 tunnel infections implicate an overall frequency of i tunnel infection every 33 months (Table 3). Twenty-one out of 26 tunnel infections were originally reported as an exit-site infection, while in the other 5 cases the exit-site had a normal appearance. There was no clear difference in the frequency of tunnel infections between the early and the later years. Of all 38 catheterrelated infections 23 were caused by Staphylococcus spp. (61%). Hernias Twenty-three children (53%) developed one or more hernias (range 1-5). Forty-one episodes of hernia were observed. Twenty-seven hernias were inguinal (66%), 14 of them right-sided and 13 left-sided. Fourteen hernias were umbilical (34%). Hernias occurred mainly in younger patients (Table 4). Inguinal hernias were more frequent in boys. Sixteen out of 27 boys developed 32 hernias and 7 out of 16 girls had nine hernias. However, mean age of the boys was considerably lower (44 months) than that of the girls (69 months); this may explain the difference. As over half of the hernias occurred within the first 3 months of C A P D , the number and percentage of hernias in the first 3 months is given in Table 5. No incarceration or strangulation occurred in the investigated population. Obstructions Obstruction occurred in 12 out of 81 implanted catheters (15%). Causes of obstruction were omental wrapping (4 cases), peritonitis (4 cases), intra-peritoneal surgery, subcutaneous catheter kinking (1 case) and a fibrin plug (1 case). Mean time after catheter implantation until obstruction was 4 months. Four obstructed catheters had to be replaced, four obstructions were solved by partial omentectomy, two obstructions disappeared after catheter manipulation [9] and two obstructions were solved by flushing with heparin or urokinase.
100
Table 3, Distribution of catheter-related infections
, Number
Catheter-related infections
Frequency 1:22.6 months 1:71.5 months 1:33 months
Leakages Fluid leakages occurred in 23 out of 81 implanted catheters (28%). Twenty out of 23 fluid leaks were at the
Table 4. Age distribution of children with or without' hernias
Mean age whole group (months) Mean age patients with hernias (months) Mean age patients without hernias (months)
Total
Boys
Girls
53.3 (n = 43) 30.6 (n = 23) 73.9 (n = 20)
43.8 (n = 27) 22.1 (n = 16) 75 (n -~ 11)
69 (n = 16) 49.6 (n = 7) 84.4 (n = 9)
379 Table 5. Hernia episodes in the first 3 months of treatment
Total Total of hernias Inguinal hernias Umbilical hernias
Boys
Girls
(n)
(%)
(n)
(%)
(n)
(%)
23 15 8
56.1 55.6 57.1
19 14 5
59.4 58 62.5
4 1 3
44.4 33.3 50
catheter insertion site, whereas three fluid leaks were from incision wounds, shortly after operation. Insertion site leakages occurred within the first 5 days after catheter implantation in ten cases; the other ten insertion site leakages were provoked by infectious complications (seven times), or obstruction (three times). Early leakage could be solved by dialysing more frequently with smaller amounts of dialysis fluid in five cases, whereas in the other five cases surgical intervention was necessary. Late leakage necessitated surgery in eight out of ten cases; only in two of these cases could the catheter be maintained.
Discussion
Incidence of peritonitis in our population is similar to that described in the literature for paediatric CAPD patient populations [1, 8]. As in the literature most of the peritonitis episodes were caused by Staphylococcus spp. The introduction of the UV-XD device seemed to have a positive effect on peritonitis incidence. However, in the same period a more aggressive approach towards catheter replacement in chronic tunnel infection and relapsing peritonitis had been adopted in our centre. We believe that this approach has also ameliorated our results as shown in Table 1. In addition, the increasing experience with this treatment has possibly played a role. Incidence of catheter-related infections is also in concordance with the literature data [2]. Just as peritonitis episodes, catheter-related infections were largely caused by Staphylococcus spp. Incidence of exit-site infections might in reality be higher than described in our study and that of others, probably because the incidence of uncomplicated exit-site infections, not systematically documented in the medical records, was underestimated. A systematic scoring system for exitsites at every outpatient visit should be advocated in all clinics. Incidence of hernias was considerably higher in our population than in the literature [6, 7, 13]. Since a dialysate volume of 40ml/kg is a common prescription in paediatric CAPD, volume is not assumed to be the cause of this higher incidence. As shown in Table 4 the patients who developed a hernia clearly had a lower mean age. If the mean age of our population is compared to that of other studies it is evident that this study represents a considerably younger population [6, 7, 13]. Of our patients 53% developed hernias. P6rez and von Lilien evaluated the literature on hernias in several adult
populations and noted ranges from 9,3% to 23.5% and 2.5% to 26.7% respectively of adult CAPD patients developing hernias, whereas yon Lilien reported an incidence of hernias of 40% in his childhood CAPD population [6, 11]. The incidence of inguinal hernia is the highest during the 1st year of life. A small patent processus vaginalis will become an inguinal hernia after CAPD treatment. At birth the processus vaginalis remains in communication with the peritoneal cavity in 80%-94%, whereas it is still completely open in 57% of infants between the ages of 4 months and 1 year [14]. In adults only 20% of patent processus vaginalis is found at autopsy [14]. The low mean age of our population seems to explain the higher frequency of hernias compared to the literature. Table 4 shows that the mean age of children developing hernias is considerably lower than that of those who did not. Prospective peritoneal scintigraphy to detect abdominal defects is of limited usefulness [5]. In our hands peritoneography could not predict all later occurring hernias. Of the implanted catheters, 15% became obstructed. Only if the obstruction is caused by infection, may catheter-manipulation [9] or flushing with heparin or urokinase [4] have a reasonable chance of success. In case of omental wrapping partial omentectomy seems to be the only effective therapy. Preventive omentectomy has been advocated [3]. To prevent obstruction during infections, heparinisation of the dialysis fluid might be effective [41 . Early leakage occurred in 12% of the inserted catheters, all of them within 5 days. The use of smaller quantities of dialysis fluid in a higher frequency or immediate surgical closure of a peritoneum defect was always successful in early leakages. A good prevention would be the postponement of dialysis for 2 weeks [10]. This is, however, disadvantageous to the majority of the patients who have to be treated with haemodialysis during that period. Since this is a difficult procedure in young children, immediate starting of the CAPD procedure is desirable. Five days after catheter implantation leakage should no longer be feared and CAPD can b'e performed according to the regular schedule. Leakages which occurred after this period were always preceded by other complications.
References
1. Balfe JW, Vigneux A, Willumsen J, Hardy BE (1980) The use of CAPD in the treatment of children with end-stage renal disease. Petit Dial Bull 1 : 35-37 2. Cantaluppi C, Castelnovo A, Scalamogna A (1985) Exit site infections in patients on continuous ambulatory peritoneal dialysis. In: Khanna R, et al (eds) Advances in CAPD: proceedings 5th annual CAPD conference, Kansas City, Canada, pp 45-48 3. Fonkalsrud EW (1990) Ask the expert: advise concerning the indications for omentectomy in babies and children receiving continuous ambulatory peritoneal dialysis. Pediatr Nephrol 4: 574 4. Gries E, Paar D, Graben N, Bock KD (1988) How much heparin intra peritoneally is necessary in CAPD. Nephron 49: 256
380 5. Kopecky RT, Frymoyer PA, Witanowski LS, Deaver Thomas F, Wojtaszek J, Reinitz ER (1990) Prospective peritoneal scintigraphy in patients beginning continuous ambulatory peritoneal dialysis. Am J Kidney Dis 3 : 228-236 6. Lilien T yon, Isidro BS, Hui Kim Yap, Forkalsrud EW, Fine RN (1987) Hernias: a frequent complication in children treated with continuous peritoneal dialysis. Am J Kidney Dis 10: 356-360 7. Lupo A, Tarchini R, Segoloni GP, Gentile MG, Canearini G, Fellin G, Salomone M, Fusaroli M, Maiorca R, Piccoli G (1988) Abdominal hernias in CAPD patients: incidence, risk factors and outcome. Adv Petit Dial 4 : 107-109 8. Mocan H, Murphy AV, Beattie TJ, McAllister TA (1988) Peritonitis in children on continuous ambulatory peritoneal dialysis. J Infect 16 : 243-251 9, O'Regan S, Garel L, Patriquin H, Yazbeck S (1988) Outflow obstruction: whiplash technique for catheter mobilization. Perit Dial Int 8 : 265-268
10. Oreopoulos DG, Baird-Helfrich G, Khanna R, Lum GM, Matthews R, Paulsen K, Twardowski ZJ, Vas SI (1987) Peritoneal catheters and exit-site practices: Current recommendations. Perit Dial Bull 7 : 130-138 11. P6rez-Font~n M, Selgs R, Miquel JL, Pardo M, Gonz~lez JA, Conesa J, Sanz A, Sfinchez-Sicilia (1986) Rupture of hernial sac as cause of massive subcutaneous dialysate leak in CAPD: diagnostic value of peritoneography. Dial and Transplant 15 : 74-77 12. Pierratos A (1984) Peritoneal dialysis glossary. Perit Dial Bull 4:2-3 13. Rocco MV, Stone WJ (1985) Abdominal hernias in chronic peritoneal dialysis patients: a review. Perit Dial Bull 5:171174 14. Rowe MI, Lloyd D A (1986) Inguinal hernia. In: Ravitch MM, Welch KJ (eds) Pediatric surgery. Year Book Medical Publishers, Chicago, pp 779-793
European Journal of
Pediatrics
9 Springer-Verlag1992
Infectious and surgical complications of childhood continuous ambulatory peritoneal dialysis J. P. M. van Asseldonk 1, C.H. Schr6der 1, R. S. V. M. Severijnen 2, M. C. J. W. de Jong 1, and L. A. H. Monnens 1 Departments of 1Paediatrics, 2paediatric Surgery, Sint Radboud University Hospital, P.O. Box 9101, NL-6500 HB Nijmegen, The Netherlands Received May 28, 1991 / Accepted in revised form September 12, 1991
Abstract. A 10-year retrospective study was p e r f o r m e d with respect to the incidence of infectious and surgical complications in a young paediatric continuous ambulatory peritoneal dialysis population of 43 children (mean age 4.5 years [range 2.5 m o n t h s - 1 5 . 8 years]). The incidence of infectious complications such as peritonitis and catheter-related infections correlated well with the results of other studies. A relatively high incidence of hernias (53%) was seen in our population, probably caused by the lower m e a n age of the children. Obstructions were caused by omental wrapping, peritonitis, or operative procedures and did not correlate with the period of catheter function. Early leakage occurred within 5 days after catheter implantation. Later leakages were preceeded by another complication, such as infection or obstruction. In early leakage, in contrast to later leakage, the catheter could be maintained. Key words: Continuous ambulatory peritoneal dialysis Surgical complications - Peritonitis - Hernias - Childhood
Introduction The most c o m m o n complication during childhood continuous ambulatory peritoneal dialysis ( C A P D ) is peritonitis. Catheter-related problems such as exit-site and tunnel infections, obstruction and leakage are also encountered. M o r e o v e r hernias are often seen in childhood C A P D [6]. We p e r f o r m e d a retrospective review of the children admitted to the peritoneal dialysis p r o g r a m m e from 1980 until 1990. A higher incidence of surgical complications was expected in our population, which was considerably younger than that presented in other series.
Patients and methods Between 1980 and 1990 a total of 43 children (27 boys and 16 girls) were admitted to the CAPD programme. The incidence of surgical complications in this population was evaluated. Mean age of the children was 4.5 years (range 2.5 months-15.8 years) at the start of treatment (Fig. 1). Total treatment experience amounted to 858 months, which is a mean patient treatment time of 20 months (range 3.5-60 months). Treatment protocols were largely unchanged throughout the whole period. Under antibiotic prophylaxis with cephazolin and gentamycin a Toronto Western Hospital II catheter was inserted in the operating theatre under general anaesthesia. Immediately after insertion dialysis was started using 20ml dialysis fluid per kg body weight (Dianeal, Baxter, Deerfield, IL, USA). Heparin (500 units/1 dialysis fluid) was added to the diolysis fluid for 3 days. Dialysate was exchanged every 3 h on the first 2 days and every 4 h on the 3rd day. On the 4th day the routine peritoneal dialysis schedule was started (40 ml/kg body weight with four exchanges daily). The Baxter spike system was used throughout the whole period. Since 1987 exchanges were preceeded by sterilizing the spike-connection by UV-irradiation (Baxter UV-XD device). Exit-site care was performed daily by the parents, by careful washing and drying, followed by spraying of the exit-site with chlorhexidine spray. The exit-site then was covered by a single sterile gauze. The incidence of surgical complications was evaluated retrospectively. Peritonitis episodes and catheter-related infections (exit-site as well as tunnel infections) were scored separately, as well as hernias (divided into inguinal and umbilical hernias), early
lO._Dumber of children (N)
8
6
4
2
Offprint requests to: C. H. Schr6der 0
Abbreviation: CAPD = continuous ambulatory peritoneal dia-
lysis
0
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
(years) Fig. 1. Age distribution of the patient population studied age
378 leakages, and obstruction of the catheter. With respect to peritonitis an episode was not considered as a new period if it occurred within 2 weeks after discontinuation of the antibiotic therapy and was caused by the same micro-organism [12].
Results
Peritonitis Eighty-two peritonitis episodes were encountered during the study period (1 episode every 10.5 patient months) of which 23 (28%) were preceeded by a tunnel infection. Eighteen patients (42%) did not suffer from peritonitis during their treatment. Since 1987, after introduction of the UV-XD device, the infection rate decreased considerably. Up to 1987 59 peritonitis episodes were observed in 398 patient months (1 episode every 6.7 months). F r o m 1987 to 1990 23 peritonitis episodes were perceived in 460 patient months (1 episode every 20 months) (Table 1). Causative micro-organisms are summarized in Table 2. Table 1. Peritonitis episodes related to treatment months and time
period
Totalperiod 1980-1986 1987-1990
CAPDmonths
Peritonitis episodes
Frequency
858 398 460
82 59 23
1:10.5 months 1: 6.7 months 1:20 months
Table 2. Causative micro-organisms of peritonitis Number Staphylococcus aureus Staphylococcus epidermidis Streptococcus viridans Pseudomonas Others Sterile
23 12 10 5 18 14
Total
82
% 28.0 14.6 12.2 6.1 21.9 17.1
Total catheter-related infections Exit-site infections Tunnel infections
38 12 26
Catheter-related infections were divided into exit-site infections and tunnel infections. Twelve out of 43 patients (28%) had 12 exit-site infections (mean duration of therapy 27.3 months), pointing to an overall frequency of 1 exit-site infection every 71.5 months. Sixteen out of 43 patients (37%) had one or more tunnel infections (mean duration of therapy 27.2 months). Their 26 tunnel infections implicate an overall frequency of i tunnel infection every 33 months (Table 3). Twenty-one out of 26 tunnel infections were originally reported as an exit-site infection, while in the other 5 cases the exit-site had a normal appearance. There was no clear difference in the frequency of tunnel infections between the early and the later years. Of all 38 catheterrelated infections 23 were caused by Staphylococcus spp. (61%). Hernias Twenty-three children (53%) developed one or more hernias (range 1-5). Forty-one episodes of hernia were observed. Twenty-seven hernias were inguinal (66%), 14 of them right-sided and 13 left-sided. Fourteen hernias were umbilical (34%). Hernias occurred mainly in younger patients (Table 4). Inguinal hernias were more frequent in boys. Sixteen out of 27 boys developed 32 hernias and 7 out of 16 girls had nine hernias. However, mean age of the boys was considerably lower (44 months) than that of the girls (69 months); this may explain the difference. As over half of the hernias occurred within the first 3 months of C A P D , the number and percentage of hernias in the first 3 months is given in Table 5. No incarceration or strangulation occurred in the investigated population. Obstructions Obstruction occurred in 12 out of 81 implanted catheters (15%). Causes of obstruction were omental wrapping (4 cases), peritonitis (4 cases), intra-peritoneal surgery, subcutaneous catheter kinking (1 case) and a fibrin plug (1 case). Mean time after catheter implantation until obstruction was 4 months. Four obstructed catheters had to be replaced, four obstructions were solved by partial omentectomy, two obstructions disappeared after catheter manipulation [9] and two obstructions were solved by flushing with heparin or urokinase.
100
Table 3, Distribution of catheter-related infections
, Number
Catheter-related infections
Frequency 1:22.6 months 1:71.5 months 1:33 months
Leakages Fluid leakages occurred in 23 out of 81 implanted catheters (28%). Twenty out of 23 fluid leaks were at the
Table 4. Age distribution of children with or without' hernias
Mean age whole group (months) Mean age patients with hernias (months) Mean age patients without hernias (months)
Total
Boys
Girls
53.3 (n = 43) 30.6 (n = 23) 73.9 (n = 20)
43.8 (n = 27) 22.1 (n = 16) 75 (n -~ 11)
69 (n = 16) 49.6 (n = 7) 84.4 (n = 9)
379 Table 5. Hernia episodes in the first 3 months of treatment
Total Total of hernias Inguinal hernias Umbilical hernias
Boys
Girls
(n)
(%)
(n)
(%)
(n)
(%)
23 15 8
56.1 55.6 57.1
19 14 5
59.4 58 62.5
4 1 3
44.4 33.3 50
catheter insertion site, whereas three fluid leaks were from incision wounds, shortly after operation. Insertion site leakages occurred within the first 5 days after catheter implantation in ten cases; the other ten insertion site leakages were provoked by infectious complications (seven times), or obstruction (three times). Early leakage could be solved by dialysing more frequently with smaller amounts of dialysis fluid in five cases, whereas in the other five cases surgical intervention was necessary. Late leakage necessitated surgery in eight out of ten cases; only in two of these cases could the catheter be maintained.
Discussion
Incidence of peritonitis in our population is similar to that described in the literature for paediatric CAPD patient populations [1, 8]. As in the literature most of the peritonitis episodes were caused by Staphylococcus spp. The introduction of the UV-XD device seemed to have a positive effect on peritonitis incidence. However, in the same period a more aggressive approach towards catheter replacement in chronic tunnel infection and relapsing peritonitis had been adopted in our centre. We believe that this approach has also ameliorated our results as shown in Table 1. In addition, the increasing experience with this treatment has possibly played a role. Incidence of catheter-related infections is also in concordance with the literature data [2]. Just as peritonitis episodes, catheter-related infections were largely caused by Staphylococcus spp. Incidence of exit-site infections might in reality be higher than described in our study and that of others, probably because the incidence of uncomplicated exit-site infections, not systematically documented in the medical records, was underestimated. A systematic scoring system for exitsites at every outpatient visit should be advocated in all clinics. Incidence of hernias was considerably higher in our population than in the literature [6, 7, 13]. Since a dialysate volume of 40ml/kg is a common prescription in paediatric CAPD, volume is not assumed to be the cause of this higher incidence. As shown in Table 4 the patients who developed a hernia clearly had a lower mean age. If the mean age of our population is compared to that of other studies it is evident that this study represents a considerably younger population [6, 7, 13]. Of our patients 53% developed hernias. P6rez and von Lilien evaluated the literature on hernias in several adult
populations and noted ranges from 9,3% to 23.5% and 2.5% to 26.7% respectively of adult CAPD patients developing hernias, whereas yon Lilien reported an incidence of hernias of 40% in his childhood CAPD population [6, 11]. The incidence of inguinal hernia is the highest during the 1st year of life. A small patent processus vaginalis will become an inguinal hernia after CAPD treatment. At birth the processus vaginalis remains in communication with the peritoneal cavity in 80%-94%, whereas it is still completely open in 57% of infants between the ages of 4 months and 1 year [14]. In adults only 20% of patent processus vaginalis is found at autopsy [14]. The low mean age of our population seems to explain the higher frequency of hernias compared to the literature. Table 4 shows that the mean age of children developing hernias is considerably lower than that of those who did not. Prospective peritoneal scintigraphy to detect abdominal defects is of limited usefulness [5]. In our hands peritoneography could not predict all later occurring hernias. Of the implanted catheters, 15% became obstructed. Only if the obstruction is caused by infection, may catheter-manipulation [9] or flushing with heparin or urokinase [4] have a reasonable chance of success. In case of omental wrapping partial omentectomy seems to be the only effective therapy. Preventive omentectomy has been advocated [3]. To prevent obstruction during infections, heparinisation of the dialysis fluid might be effective [41 . Early leakage occurred in 12% of the inserted catheters, all of them within 5 days. The use of smaller quantities of dialysis fluid in a higher frequency or immediate surgical closure of a peritoneum defect was always successful in early leakages. A good prevention would be the postponement of dialysis for 2 weeks [10]. This is, however, disadvantageous to the majority of the patients who have to be treated with haemodialysis during that period. Since this is a difficult procedure in young children, immediate starting of the CAPD procedure is desirable. Five days after catheter implantation leakage should no longer be feared and CAPD can b'e performed according to the regular schedule. Leakages which occurred after this period were always preceded by other complications.
References
1. Balfe JW, Vigneux A, Willumsen J, Hardy BE (1980) The use of CAPD in the treatment of children with end-stage renal disease. Petit Dial Bull 1 : 35-37 2. Cantaluppi C, Castelnovo A, Scalamogna A (1985) Exit site infections in patients on continuous ambulatory peritoneal dialysis. In: Khanna R, et al (eds) Advances in CAPD: proceedings 5th annual CAPD conference, Kansas City, Canada, pp 45-48 3. Fonkalsrud EW (1990) Ask the expert: advise concerning the indications for omentectomy in babies and children receiving continuous ambulatory peritoneal dialysis. Pediatr Nephrol 4: 574 4. Gries E, Paar D, Graben N, Bock KD (1988) How much heparin intra peritoneally is necessary in CAPD. Nephron 49: 256
380 5. Kopecky RT, Frymoyer PA, Witanowski LS, Deaver Thomas F, Wojtaszek J, Reinitz ER (1990) Prospective peritoneal scintigraphy in patients beginning continuous ambulatory peritoneal dialysis. Am J Kidney Dis 3 : 228-236 6. Lilien T yon, Isidro BS, Hui Kim Yap, Forkalsrud EW, Fine RN (1987) Hernias: a frequent complication in children treated with continuous peritoneal dialysis. Am J Kidney Dis 10: 356-360 7. Lupo A, Tarchini R, Segoloni GP, Gentile MG, Canearini G, Fellin G, Salomone M, Fusaroli M, Maiorca R, Piccoli G (1988) Abdominal hernias in CAPD patients: incidence, risk factors and outcome. Adv Petit Dial 4 : 107-109 8. Mocan H, Murphy AV, Beattie TJ, McAllister TA (1988) Peritonitis in children on continuous ambulatory peritoneal dialysis. J Infect 16 : 243-251 9, O'Regan S, Garel L, Patriquin H, Yazbeck S (1988) Outflow obstruction: whiplash technique for catheter mobilization. Perit Dial Int 8 : 265-268
10. Oreopoulos DG, Baird-Helfrich G, Khanna R, Lum GM, Matthews R, Paulsen K, Twardowski ZJ, Vas SI (1987) Peritoneal catheters and exit-site practices: Current recommendations. Perit Dial Bull 7 : 130-138 11. P6rez-Font~n M, Selgs R, Miquel JL, Pardo M, Gonz~lez JA, Conesa J, Sanz A, Sfinchez-Sicilia (1986) Rupture of hernial sac as cause of massive subcutaneous dialysate leak in CAPD: diagnostic value of peritoneography. Dial and Transplant 15 : 74-77 12. Pierratos A (1984) Peritoneal dialysis glossary. Perit Dial Bull 4:2-3 13. Rocco MV, Stone WJ (1985) Abdominal hernias in chronic peritoneal dialysis patients: a review. Perit Dial Bull 5:171174 14. Rowe MI, Lloyd D A (1986) Inguinal hernia. In: Ravitch MM, Welch KJ (eds) Pediatric surgery. Year Book Medical Publishers, Chicago, pp 779-793
