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AUGMENTING THE AUGMENTED BLADDER: TREATMENT OF THE CONTRACTILE BOWEL SEGMENT
0022-5347/98/1603-0854$03.00/0
Vol. 160,854-857, September 1998 Printed in U.S.A.
THE JOURNAL OF UROLOGY
Copyright 8 1998 by AMERICAN UROLOGICAL ASSOCIATION, INC.
AUGMENTING THE AUGMENTED BLADDER: TREATMENT OF THE CONTRACTILE BOWEL SEGMENT JOHN C. POPE, W , MICHAEL A. KEATING, ANTHONY J. CASALE
AND
RICHARD C. RINK
From the Division of Pediatric Urology, James Whitcomb Riley Hospital for Children, and Indiana University Medical Center, Indianapolis, Indiana
ABSTRACT
Purpose: Bowel used for bladder reconstruction regardless of detubularization occasionally retains its contractile properties. Of 323 patients who underwent primary enterocystoplasty we identified 19 who continue to have high pressure bladder contractions and required augmentation of the previously augmented bladder. Materials and Methods: Reason for repeat augmentation, upper tract changes, original and secondary bowel segments used, and urodynamic findings were evaluated in all patients. Current status and followup also were noted. Results: After initial augmentation 8 patients had persistent incontinence, 5 bladder perforation, 3 isolated upper tract changes, 2 incontinence and bladder perforation, and 1incontinence plus intractable pain. Preoperative urodynamics revealed detrusor pressures from 30 to 100 cm. water. All patients had adequate bladder outlet resistance. The original bowel segments used were sigmoid in 12 cases, stomach in 4, ileum in 2 and cecum in 1. Bowel segments for reaugmentation were ileum in 16 cases and sigmoid in 3. Of the 11patients with incontinence 10 are now dry. All cases of upper tract changes resolved. Mean followup since re-augmentation is 52 months. Conclusions: If the outcome of bladder augmentation is less than optimal, it is important to reevaluate the bladder dynamics. In rare instances these patients may continue to have high pressure contractions with a functionally small bladder capacity. In such situations reaugmentation with an additional bowel segment is an excellent alternative to a difficult clinical problem and provides good results in the vast majority of cases. This treatment may not totally alleviate the contractions but it does decrease them and increase the volumes a t which the contractions occur, making them no longer clinically or functionally significant. KEY WORDS: bladder, urinary tract, intestines, stomach
A major advance in pediatric urology during the last 20 years is reconstruction of the lower urinary tract using bowel. We have since gained much knowledge about the physical and physiological effects of interposing bowel in the urinary tract. It is known that any segment of bowel from stomach to sigmoid colon can be used successfully to augment the bladder provided it is detubularized and reconfigured into a sphere. This spherical shape provides several advantages, including maximizing the volume achieved for any given surface area of bowel, blunting the native bowel contractility and providing overall compliance.1-2The belief has been that detubularizing and reconfiguring a given bowel segment will prevent continued rhythmic sinusoidal contractions. We recently identified a subset of patients a t our institution who had poor results after primary augmentation. Further investigation revealed retained significant rhythmic, high pressure contractions of the augmented bladder, which ultimately required secondary augmentation with an additional piece of bowel. The clinical course of these patients is described.
and urethral urodynamics before and after secondary augmentation, original and secondary bowel segments used, results after secondary augmentation including complications and mean followup were evaluated for each patient.
METHODS
TABLE1. Categorization of primary bladder augmentations based on bowel segment used
RESULTS
From 1978 until 1997, 323 primary gastrointestinocystoplasties with various bowel segments were performed at our institution (table 1).From this group we identified 12 girls and 7 boys who ultimately required secondary augmentation (table 2). Patient age at primary augmentation was 9.8 years (range 1 to 13). The interval from primary to secondary augmentation was 5 years (range 0.6 to 10.7). The bowel segments used for primary augmentation and the incidence of re-augmentation per bowel segment are shown in table 3. Clinical presentation after initial augmentation included incontinence in 8 cases, spontaneous perforation of the augmented bladder in 5, upper urinary tract changes (new onset
All cases of primary augmentation cystoplasty during the last 19 years were reviewed. Of this group we identified a subset of patients who ultimately required secondary augmentation, and clinical course was examined in-depth. Underlying diagnosis, time from primary to secondary augmentation, clinical problems after initial augmentation, bladder Accepted for publication April 17, 1998.
854
No. (70)
Ileal Sigmoid Ileocecal Gastric Composites Transverse colon
145 (45) 87 (27) 48 (15) 39 (12) 3 (0.8) l(0.2)
855
AUGMENTING PREVIOUSLY AUGMENTED BLADDER TABLE2 . Underlying diagnosis of 19 patients requiring secondary bladder augmentation No.
Myelomeningocele Cloaca1 exstrophy Classic exstrophy Nonneurogenic neurogenic bladder Other Sacral awnesis
10 2 2 2
2 1
TABLE3. Initial bowel segments used in patients requiring . secondary bladder augmentation Initial Bowel Segment Sigmoid Gastric Ileocecal Ileal Total
NoSTotal No. (%)
12/87 (13.8) 4/39 (10.3) l/48 (2.1) 2/145 (1.4) 19/323 (5.9)
of hydronephrosis andor vesicoureteral reflux) in 3, incontinence and spontaneous bladder perforation in 2, and incontinence and intractable pelvic pain in 1. Urodynamic evaluation was performed after primary augmentation in 15 patients, including 11 with incontinence, 3 with upper tract changes and 1with recurrent spontaneous perforation. The patient with intractable pelvic pain had associated high pressure bladder contractions that occurred during the episodes of pain. The remaining 4 cases were re-augmented for recurrent bladder perforation and urodynamics were not performed. Urodynamic studies revealed high pressure (greater than 40 cm. water at volumes less than 200 cc3) rhythmic contractions of the augmented bladder in 12 cases, small capacity reservoir in 3, and a poorly compliant augmented bladder in 1(fig. 1). All 19 patients had urethral leak point pressures ranging from 40 to 100 cm. water. Six patients had undergone prior surgical bladder neck procedures for continence. The bowel segments used for secondary relative to those used for primary augmentation are shown in table 4. After secondary augmentation 10 of the 11incontinent patients are dry and in all patients with upper tract changes hydronephrosis resolved. There were 2 complications. The patient who was initially incontinent with intractable pelvic pain is now continent but has persistent pain, and the patient with incontinence and recurrent spontaneous bladder perforations is persistently wet and has had yet another perforation after the secondary augmentation. Urodynamic studies after secondary augmentation in 4 patients showed increased capac-
TABLE4. Categorization of patients requiring secondary bladder augmentation based on which bowel segment was used for the secondary relative to the segment used for the initial augmentation No. h. Primary Segment Secondary Sement 12 4 2 1
Sigmoid Stomach Ileum
cecum
Ileum Ileum Sigmoid Sigmoid
ity, decreased maximum filling pressure and decreased intensity of contractions (fig. 2). This group of patients has been followed for a mean of 69 months (range 35 to 155). DISCUSSION
It is well documented that bowel segments used for reconstruction of the lower urinary tract can retain their intrinsic contractile properties. Subsequently, it was recommended that all bowel used for this type of reconstruction be detubularized and reconfigured in part to alleviate these persistent contractions.1- However, it has become evident that despite all efforts to minimize these persistent contractions, some bowel segments continue to have clinically significant, high pressure contractions. From a large population of primary gastrointestinocystoplasties, we identified a small subset of patients whose clinical outcome was less than optimal after initial augmentation. Further evaluation revealed continued high pressure phasic contractions from augmented bladder ultimately requiring further surgical intervention. Numerous authors have reported mass contractions generating high pressures ranging from 40 to 110 cm. water in bladders augmented with ileum, colon and stomach.3-10 In a study of patients who had undergone ileal or ileocecal augmentation significant contractions associated with urge incontinence persisted in 16%." In another comparison study, 60% of patients with detubularized right colon and 42%with detubularized ileum had contractions greater than 15 cm. water.3 However, clinically significant contractions, arbitrarily defined as greater than 40 cm. water at volumes less than 200 cc, were only observed in 10% of the right colon and in none of the ileal segments and, it thus, was concluded that ileum was superior but only at large volumes. Cecal reservoirs have had higher resting pressures and greater motor activity at equal volumes than ileal reservoirs.12 In general, however, it is believed that adequate compliant reservoirs can be achieved with all segments of bowel provided certain technical points are applied. Of our 323 patients 19 (5.9%) had clinically significant problems due to the contractile activity of the augmented
FIG.1. Typical urodpamic study shows continued, rhythmx, high pressure contractions in patient who had previously undergone bladder augmentation with bowel.
856
AUGMENTING PREVIOUSLY AUGMENTED BLADDER J
FIG. 2. A, vodynamic study reveals significant contractions within bladder initially augmented (A%) with gastric segment. B, same atient after secondary augmentation with ileal segment. Contractions are still present but have been shifted to right and now occur at much bgher, clinically insignificant volumes.
bladder. These contractions resulted in persistent incontinence, delayed perforation or upper tract changes in the form of hydronephrosis and/or vesicoureteral reflux. A secondary patch augmentation improved the clinical status in 18 of 19 patients (95%).The seemingly higher risk for persistent contractions in sigmoid segments is likely due to the way the segments were configured. Essentially all configurations were created using the technique described by Mitchell in which the sigmoid was opened along the antimesenteric border, the 2 ends were closed and the segment was attached to the bladder in a cup type configuration (fig. 3, B).13In retro-
spect, this technique does not seem to break up the unit contractions of the bowel as well as more aggressive reconfigurations (fig. 3, C). Others have not had these problems with persistent contractions and noncompliance with the S-type re~onfiguration.~ The higher incidence of re-augmentation in gastric segments appears t o be related to the size of the gastric patch. Since observing these contractions, Adams et a1 used a larger gastric segment from the greater curvature and noted improved urodynamic results atker augmentation with less prominent contractions.14Given proper reconfiguration and
FIG.3. A, sigmoid segment of adequate length is removed from astrointestinal tract and colocolostomy is performed. B, in Mitchell sigmoid cystoplasty 2 opened ends are anastornosed, antimesenteric%order is incised and segment is anastomosed to bivalved bladder. C, opened sigmoid segment is now more commonly reconfigured into U or S configuration.
AUGMENTING PREVIOUSLY AUGMENTED BLADDER
size, all segments should have virtually the same risk of significant contractions when used as an augment segment. It is also important t o note that secondary augmentation does not obliterate the contractions. The contractions still occur but the pressure/volume curve has been shifted t o the right, and the contractions are dampened and now occur at volumes that are not clinically significant provided the patient is compliant with intermittent catheterization and timely emptying of the reservoir (fig. 2). It is recognized that all segments contract at low amplitude as filling progresses. The goal of primary or secondary augmentation should be to create a reservoir that stores urine at acceptable volumes and pressures, and does not generate high pressure contractions at usual and customary volumes. Finally, the comparison of our subset to the total number of augmented cases with incontinence or high pressure bladder contractions is difficult. Patients who do not have clinical problems after augmentation are not routinely evaluated with urodynamics. Likewise, it is difficult to compare patients with incontinence due to low bladder outlet resistance to those with incontinence due to high pressure contractions after augmentation. The emphasis of our study is that patients who have clinical problems after augmentation that can be attributed to high pressure bladder contractions (hydronephrosis, incontinence or bladder perforation) need to undergo repeat urodynamic evaluation. If high pressure contractions persist anticholinergic medication and increased frequency of intermittent catheterization should be initiated. Secondary augmentation should be considered in patients in whom medical management fails and clinical problems continue. CONCLUSIONS
It is well recognized that a small subset of patients undergoing primary bladder augmentation have persistent clinically significant peristaltic contractions of the bowel segment. If the outcome of initial bladder augmentation is less than optimal, it is important to reevaluate the bladder dynamics. Despite augmentation, a noncompliant reservoir with high pressure contractions may persist. In these patients secondary augmentation with additional bowel will decrease the contractions and increase the volume at which they occur, which will alleviate the associated clinical problem in most cases. Thus, re-augmentation is an excellent alternative for the treatment of this clinically challenging problem.
857
REFERENCES
1. Hinman, F., Jr.: Selection of intestinal segments for bladder substitution: physical and physiological characteristics. J. Urol., 139 519, 1988. 2. Koff, S.A,: Guidelines to determine the size and shape of intestinal segments used for reconstruction. J. Urol., part 2, 140: 1150,1988. 3. Goldwasser, B., Barrett, D. M., Webster, G. D. and Kramer, S. A.: Cystometric properties of ileum and right colon after bladder augmentation, substitution or replacement. J. Urol., 138 1007, 1986. 4. Adams, M. C., Mitchell, M. E. and Rink, R. C.: Gastrocystoplasty: an alternative solution to the problem of urological reconstruction in the severely compromised patient. J. Urol., part 2,140.1152, 1988. 5. Lytton, B. and Green, D. F.: Urodynamic studies in patients undergoing bladder replacement surgery. J. Urol., 141: 1394, 1989. 6. Thuroff, J. W., Alken, P. and Hohenfellner, R.: The MAIN2 pouch (mixed augmentation with ileum ‘n’ zecum) for bladder augmentation and continent diversion. In: Bladder Reconstruction and Continent Urinary Diversion. Edited by L. R. King, A. R. Stone and G. D. Webster. Chicago: Yearbook Medical Publishers, chapt. 18,p. 252,1987. 7. Sidi, A. A., Reinberg, Y. and Gonzalez, R.: Influence of intestinal segment and configuration on the outcome of augmentation enterocystoplasty. J . Urol., 136: 1201, 1986. 8. Atala, A.,Bauer, S. B., Hendren, W. H. and Retik, A. B.: The effect of gastric augmentation on bladder function. J . Urol., 149 1099,1993. 9. Gosalbez, R., Jr., Woodard, J . R., Broecker, B. H., Parrott, T. S. and Massad, C.: The use of stomach in pediatric urinary reconstruction. J. Urol., part 2,1M):438, 1993. 10. Decter, R. M., Bauer, S. B., Mandell, J., Colodny, A. H. and Retik, A. B.: Small bowel augmentation in children with neurogenic bladder: an initial report of urodynamic findings. J. Urol., part 2, 138 1014,1987. 11. Robertson, A. S.,Davies, J. B., Webb, R. J. and Neal, D. E.: Bladder augmentation and replacement. Urodynamic and clinical review of 25 patients. Brit. J. Urol., 68:590, 1991. 12. Berglund, B., Kock, N. G., NorlBn, L. and Philipson, B. M.: Volume capacity and pressure characteristics of the continent ileal reservoir used for urinary diversion. J. Urol., 131: 29, 1987. 13. Mitchell, M. E.: Use of bowel in undiversion. Urol. Clin. N. Amer., 13: 349, 1986. 14. Adams, M. C., Bihrle, R. and Rink, R. C.: The use of stomach in urologic reconstruction. AUA Update Series, 1 4 218, 1995.
Vol. 160,854-857, September 1998 Printed in U.S.A.
THE JOURNAL OF UROLOGY
Copyright 8 1998 by AMERICAN UROLOGICAL ASSOCIATION, INC.
AUGMENTING THE AUGMENTED BLADDER: TREATMENT OF THE CONTRACTILE BOWEL SEGMENT JOHN C. POPE, W , MICHAEL A. KEATING, ANTHONY J. CASALE
AND
RICHARD C. RINK
From the Division of Pediatric Urology, James Whitcomb Riley Hospital for Children, and Indiana University Medical Center, Indianapolis, Indiana
ABSTRACT
Purpose: Bowel used for bladder reconstruction regardless of detubularization occasionally retains its contractile properties. Of 323 patients who underwent primary enterocystoplasty we identified 19 who continue to have high pressure bladder contractions and required augmentation of the previously augmented bladder. Materials and Methods: Reason for repeat augmentation, upper tract changes, original and secondary bowel segments used, and urodynamic findings were evaluated in all patients. Current status and followup also were noted. Results: After initial augmentation 8 patients had persistent incontinence, 5 bladder perforation, 3 isolated upper tract changes, 2 incontinence and bladder perforation, and 1incontinence plus intractable pain. Preoperative urodynamics revealed detrusor pressures from 30 to 100 cm. water. All patients had adequate bladder outlet resistance. The original bowel segments used were sigmoid in 12 cases, stomach in 4, ileum in 2 and cecum in 1. Bowel segments for reaugmentation were ileum in 16 cases and sigmoid in 3. Of the 11patients with incontinence 10 are now dry. All cases of upper tract changes resolved. Mean followup since re-augmentation is 52 months. Conclusions: If the outcome of bladder augmentation is less than optimal, it is important to reevaluate the bladder dynamics. In rare instances these patients may continue to have high pressure contractions with a functionally small bladder capacity. In such situations reaugmentation with an additional bowel segment is an excellent alternative to a difficult clinical problem and provides good results in the vast majority of cases. This treatment may not totally alleviate the contractions but it does decrease them and increase the volumes a t which the contractions occur, making them no longer clinically or functionally significant. KEY WORDS: bladder, urinary tract, intestines, stomach
A major advance in pediatric urology during the last 20 years is reconstruction of the lower urinary tract using bowel. We have since gained much knowledge about the physical and physiological effects of interposing bowel in the urinary tract. It is known that any segment of bowel from stomach to sigmoid colon can be used successfully to augment the bladder provided it is detubularized and reconfigured into a sphere. This spherical shape provides several advantages, including maximizing the volume achieved for any given surface area of bowel, blunting the native bowel contractility and providing overall compliance.1-2The belief has been that detubularizing and reconfiguring a given bowel segment will prevent continued rhythmic sinusoidal contractions. We recently identified a subset of patients a t our institution who had poor results after primary augmentation. Further investigation revealed retained significant rhythmic, high pressure contractions of the augmented bladder, which ultimately required secondary augmentation with an additional piece of bowel. The clinical course of these patients is described.
and urethral urodynamics before and after secondary augmentation, original and secondary bowel segments used, results after secondary augmentation including complications and mean followup were evaluated for each patient.
METHODS
TABLE1. Categorization of primary bladder augmentations based on bowel segment used
RESULTS
From 1978 until 1997, 323 primary gastrointestinocystoplasties with various bowel segments were performed at our institution (table 1).From this group we identified 12 girls and 7 boys who ultimately required secondary augmentation (table 2). Patient age at primary augmentation was 9.8 years (range 1 to 13). The interval from primary to secondary augmentation was 5 years (range 0.6 to 10.7). The bowel segments used for primary augmentation and the incidence of re-augmentation per bowel segment are shown in table 3. Clinical presentation after initial augmentation included incontinence in 8 cases, spontaneous perforation of the augmented bladder in 5, upper urinary tract changes (new onset
All cases of primary augmentation cystoplasty during the last 19 years were reviewed. Of this group we identified a subset of patients who ultimately required secondary augmentation, and clinical course was examined in-depth. Underlying diagnosis, time from primary to secondary augmentation, clinical problems after initial augmentation, bladder Accepted for publication April 17, 1998.
854
No. (70)
Ileal Sigmoid Ileocecal Gastric Composites Transverse colon
145 (45) 87 (27) 48 (15) 39 (12) 3 (0.8) l(0.2)
855
AUGMENTING PREVIOUSLY AUGMENTED BLADDER TABLE2 . Underlying diagnosis of 19 patients requiring secondary bladder augmentation No.
Myelomeningocele Cloaca1 exstrophy Classic exstrophy Nonneurogenic neurogenic bladder Other Sacral awnesis
10 2 2 2
2 1
TABLE3. Initial bowel segments used in patients requiring . secondary bladder augmentation Initial Bowel Segment Sigmoid Gastric Ileocecal Ileal Total
NoSTotal No. (%)
12/87 (13.8) 4/39 (10.3) l/48 (2.1) 2/145 (1.4) 19/323 (5.9)
of hydronephrosis andor vesicoureteral reflux) in 3, incontinence and spontaneous bladder perforation in 2, and incontinence and intractable pelvic pain in 1. Urodynamic evaluation was performed after primary augmentation in 15 patients, including 11 with incontinence, 3 with upper tract changes and 1with recurrent spontaneous perforation. The patient with intractable pelvic pain had associated high pressure bladder contractions that occurred during the episodes of pain. The remaining 4 cases were re-augmented for recurrent bladder perforation and urodynamics were not performed. Urodynamic studies revealed high pressure (greater than 40 cm. water at volumes less than 200 cc3) rhythmic contractions of the augmented bladder in 12 cases, small capacity reservoir in 3, and a poorly compliant augmented bladder in 1(fig. 1). All 19 patients had urethral leak point pressures ranging from 40 to 100 cm. water. Six patients had undergone prior surgical bladder neck procedures for continence. The bowel segments used for secondary relative to those used for primary augmentation are shown in table 4. After secondary augmentation 10 of the 11incontinent patients are dry and in all patients with upper tract changes hydronephrosis resolved. There were 2 complications. The patient who was initially incontinent with intractable pelvic pain is now continent but has persistent pain, and the patient with incontinence and recurrent spontaneous bladder perforations is persistently wet and has had yet another perforation after the secondary augmentation. Urodynamic studies after secondary augmentation in 4 patients showed increased capac-
TABLE4. Categorization of patients requiring secondary bladder augmentation based on which bowel segment was used for the secondary relative to the segment used for the initial augmentation No. h. Primary Segment Secondary Sement 12 4 2 1
Sigmoid Stomach Ileum
cecum
Ileum Ileum Sigmoid Sigmoid
ity, decreased maximum filling pressure and decreased intensity of contractions (fig. 2). This group of patients has been followed for a mean of 69 months (range 35 to 155). DISCUSSION
It is well documented that bowel segments used for reconstruction of the lower urinary tract can retain their intrinsic contractile properties. Subsequently, it was recommended that all bowel used for this type of reconstruction be detubularized and reconfigured in part to alleviate these persistent contractions.1- However, it has become evident that despite all efforts to minimize these persistent contractions, some bowel segments continue to have clinically significant, high pressure contractions. From a large population of primary gastrointestinocystoplasties, we identified a small subset of patients whose clinical outcome was less than optimal after initial augmentation. Further evaluation revealed continued high pressure phasic contractions from augmented bladder ultimately requiring further surgical intervention. Numerous authors have reported mass contractions generating high pressures ranging from 40 to 110 cm. water in bladders augmented with ileum, colon and stomach.3-10 In a study of patients who had undergone ileal or ileocecal augmentation significant contractions associated with urge incontinence persisted in 16%." In another comparison study, 60% of patients with detubularized right colon and 42%with detubularized ileum had contractions greater than 15 cm. water.3 However, clinically significant contractions, arbitrarily defined as greater than 40 cm. water at volumes less than 200 cc, were only observed in 10% of the right colon and in none of the ileal segments and, it thus, was concluded that ileum was superior but only at large volumes. Cecal reservoirs have had higher resting pressures and greater motor activity at equal volumes than ileal reservoirs.12 In general, however, it is believed that adequate compliant reservoirs can be achieved with all segments of bowel provided certain technical points are applied. Of our 323 patients 19 (5.9%) had clinically significant problems due to the contractile activity of the augmented
FIG.1. Typical urodpamic study shows continued, rhythmx, high pressure contractions in patient who had previously undergone bladder augmentation with bowel.
856
AUGMENTING PREVIOUSLY AUGMENTED BLADDER J
FIG. 2. A, vodynamic study reveals significant contractions within bladder initially augmented (A%) with gastric segment. B, same atient after secondary augmentation with ileal segment. Contractions are still present but have been shifted to right and now occur at much bgher, clinically insignificant volumes.
bladder. These contractions resulted in persistent incontinence, delayed perforation or upper tract changes in the form of hydronephrosis and/or vesicoureteral reflux. A secondary patch augmentation improved the clinical status in 18 of 19 patients (95%).The seemingly higher risk for persistent contractions in sigmoid segments is likely due to the way the segments were configured. Essentially all configurations were created using the technique described by Mitchell in which the sigmoid was opened along the antimesenteric border, the 2 ends were closed and the segment was attached to the bladder in a cup type configuration (fig. 3, B).13In retro-
spect, this technique does not seem to break up the unit contractions of the bowel as well as more aggressive reconfigurations (fig. 3, C). Others have not had these problems with persistent contractions and noncompliance with the S-type re~onfiguration.~ The higher incidence of re-augmentation in gastric segments appears t o be related to the size of the gastric patch. Since observing these contractions, Adams et a1 used a larger gastric segment from the greater curvature and noted improved urodynamic results atker augmentation with less prominent contractions.14Given proper reconfiguration and
FIG.3. A, sigmoid segment of adequate length is removed from astrointestinal tract and colocolostomy is performed. B, in Mitchell sigmoid cystoplasty 2 opened ends are anastornosed, antimesenteric%order is incised and segment is anastomosed to bivalved bladder. C, opened sigmoid segment is now more commonly reconfigured into U or S configuration.
AUGMENTING PREVIOUSLY AUGMENTED BLADDER
size, all segments should have virtually the same risk of significant contractions when used as an augment segment. It is also important t o note that secondary augmentation does not obliterate the contractions. The contractions still occur but the pressure/volume curve has been shifted t o the right, and the contractions are dampened and now occur at volumes that are not clinically significant provided the patient is compliant with intermittent catheterization and timely emptying of the reservoir (fig. 2). It is recognized that all segments contract at low amplitude as filling progresses. The goal of primary or secondary augmentation should be to create a reservoir that stores urine at acceptable volumes and pressures, and does not generate high pressure contractions at usual and customary volumes. Finally, the comparison of our subset to the total number of augmented cases with incontinence or high pressure bladder contractions is difficult. Patients who do not have clinical problems after augmentation are not routinely evaluated with urodynamics. Likewise, it is difficult to compare patients with incontinence due to low bladder outlet resistance to those with incontinence due to high pressure contractions after augmentation. The emphasis of our study is that patients who have clinical problems after augmentation that can be attributed to high pressure bladder contractions (hydronephrosis, incontinence or bladder perforation) need to undergo repeat urodynamic evaluation. If high pressure contractions persist anticholinergic medication and increased frequency of intermittent catheterization should be initiated. Secondary augmentation should be considered in patients in whom medical management fails and clinical problems continue. CONCLUSIONS
It is well recognized that a small subset of patients undergoing primary bladder augmentation have persistent clinically significant peristaltic contractions of the bowel segment. If the outcome of initial bladder augmentation is less than optimal, it is important to reevaluate the bladder dynamics. Despite augmentation, a noncompliant reservoir with high pressure contractions may persist. In these patients secondary augmentation with additional bowel will decrease the contractions and increase the volume at which they occur, which will alleviate the associated clinical problem in most cases. Thus, re-augmentation is an excellent alternative for the treatment of this clinically challenging problem.
857
REFERENCES
1. Hinman, F., Jr.: Selection of intestinal segments for bladder substitution: physical and physiological characteristics. J. Urol., 139 519, 1988. 2. Koff, S.A,: Guidelines to determine the size and shape of intestinal segments used for reconstruction. J. Urol., part 2, 140: 1150,1988. 3. Goldwasser, B., Barrett, D. M., Webster, G. D. and Kramer, S. A.: Cystometric properties of ileum and right colon after bladder augmentation, substitution or replacement. J. Urol., 138 1007, 1986. 4. Adams, M. C., Mitchell, M. E. and Rink, R. C.: Gastrocystoplasty: an alternative solution to the problem of urological reconstruction in the severely compromised patient. J. Urol., part 2,140.1152, 1988. 5. Lytton, B. and Green, D. F.: Urodynamic studies in patients undergoing bladder replacement surgery. J. Urol., 141: 1394, 1989. 6. Thuroff, J. W., Alken, P. and Hohenfellner, R.: The MAIN2 pouch (mixed augmentation with ileum ‘n’ zecum) for bladder augmentation and continent diversion. In: Bladder Reconstruction and Continent Urinary Diversion. Edited by L. R. King, A. R. Stone and G. D. Webster. Chicago: Yearbook Medical Publishers, chapt. 18,p. 252,1987. 7. Sidi, A. A., Reinberg, Y. and Gonzalez, R.: Influence of intestinal segment and configuration on the outcome of augmentation enterocystoplasty. J . Urol., 136: 1201, 1986. 8. Atala, A.,Bauer, S. B., Hendren, W. H. and Retik, A. B.: The effect of gastric augmentation on bladder function. J . Urol., 149 1099,1993. 9. Gosalbez, R., Jr., Woodard, J . R., Broecker, B. H., Parrott, T. S. and Massad, C.: The use of stomach in pediatric urinary reconstruction. J. Urol., part 2,1M):438, 1993. 10. Decter, R. M., Bauer, S. B., Mandell, J., Colodny, A. H. and Retik, A. B.: Small bowel augmentation in children with neurogenic bladder: an initial report of urodynamic findings. J. Urol., part 2, 138 1014,1987. 11. Robertson, A. S.,Davies, J. B., Webb, R. J. and Neal, D. E.: Bladder augmentation and replacement. Urodynamic and clinical review of 25 patients. Brit. J. Urol., 68:590, 1991. 12. Berglund, B., Kock, N. G., NorlBn, L. and Philipson, B. M.: Volume capacity and pressure characteristics of the continent ileal reservoir used for urinary diversion. J. Urol., 131: 29, 1987. 13. Mitchell, M. E.: Use of bowel in undiversion. Urol. Clin. N. Amer., 13: 349, 1986. 14. Adams, M. C., Bihrle, R. and Rink, R. C.: The use of stomach in urologic reconstruction. AUA Update Series, 1 4 218, 1995.