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Study of antireflux nipple valves of Kock ileal urinary reservoir experimental investigation in dogs
STUDY OF ANTIREFLUX NIPPLE VALVES OF
KOCK ILEAL URINARY RESERVOIR Experimental Investigation in Dogs MARK H. KAWACHI, M.D. THOMAS E. AHLERING, M.D.
STUART D. BOYD, M.D. DONALD G. SKINNER, M.D. GARY LIESKOVSKY, M.D.
From the Division of Urology; University of Southern California School of Medicine, Los Angeles, California
ABSTRACT--To better assess the construction, maintenance, and function of the Kock ileali urinary reservoir with its continent antirefluxing nipple valves, laboratory investigations in dog~I were done simultaneously with clinical trials in humans in 1983. Fifteen dogs underwent creatio~i of hemi-Kock ileal reservoirs (without the efferent valve and limb) that were anastomosed to thei~i bladders as enterocystoplasties. The afferent antirefluxing nipple valves were intussuscepted after cm of underlying mesentery had been removed. The nipples were further stabilized with metal an~~:' absorbable (Polysorb) staples and Marlex collars. The right ureters were anastomosed to the af ferent limb of the reservoirs with the contralateral systems left intact as controls. Ten dogs were ab~ to be followed at the vivaria for twelve to thirty-six months and then studied. All nipple valv~ remained intact, viable, and nonrefluxing without revision. All kidneys remained histologicall normal except those in dogs with dilated ureters secondary to ureteroileal stenosis with concurren calculi formation. Calculi formed on exposed metal staples and Marlex. The absorbable stapl~ were found to promote appropriate healing and were never the nidus for stone formation. It ap: pears that the int~n~S;scepted mpplevalv~ (wzth its mesentery removed) is reproducible and fu tionally reliable in p eventing eft x. t also appears these valves can histologically p r e s e ~ diverted kidneys if the upper u~inary tract drainage is normal and calculi are minimized. T ~ proper placement of taples a d the elimination of Marlex-anchoring collars are indicated ta! minimize calculi, i!!
In 1982, Koek and associates ~ first published in the United States their experience with the continent ileal urinary reselwoir. This major contribution to urology represented more than ten years of experimental and clinical study. ~° Their approach combined and adapted many older ideas with several new techniques and opened the door to a classic advance in urologic surgery. It was specifically this work that prompted our own investigations and clinical trials into the continent urinary diversion.
80
The most important factor in the success 01 the Koek ileal urinary reservoir is the creati6~ and maintenance of nipple valves to prevent re flux and insure continence. Both Kock~ an~ Leisinger, Sehauweeher, and Sauberli TM h~i published short-term animal studies of thN valves that were extremely important in e s t ~ lishing their efficacy. While they had s h o ~ that the valves could be made to work, h ~ ever, the revision rate and potential c ~ plication of the valves were high T h e r e f ~
UROLOGY / JANUARY1991 / VOLUME XXXVII, NL;MBE~1
1,.
!......e/' {(
' ...%
I
15cm afferent limb
./
12cm reservoir portion
y 3cm efferent limb
FmURE 1. F o r t y - t w o cm loop o_f ileum is isolated and appropriate limb lengths marked.
12 cm reservoir portion ;~simultaneous to beginning our own clinical itrials in 1982 with the ileal urinary reservoir in humans, laboratory experiments were begun to 'further study the continent nipple valves. Our goals prior to the study were to create a ilpermanent nipple valve and to investigate the imaterials and methods that would minimize t h e problems associated with this valve's conStruction and function. Specifically we wanted to investigate the use of staples, both metal and ::.!absorbable type staples (Polysorb), and ex~amine their concomitant problems with stone formation in the urinary tract, look at the )Marlex fixation collars at the base of the valves, ..:',study the viability of the nipple if the underly:i!ng mesentery was removed prior to intussusception, and most important study the long:{erm effects of the valves on the kidneys and upper urinary tracts. ~:" To this end, h e m i - K o e k ileal reservoirs ::i(without the efferent valves and limbs) were ;created in dogs and anastomosed to the bladder ,as an enteroeystoplasty, The dogs were followed !for twelve to thirty-six months and studied. i;
Material and Methods :Between January, 1983, and January, 1984, ~!5 adult mongrel dogs (11 females and 4 males), :}'eighing between 24 and 30 kg, were prepared iand operated on using the same standardized technique at a University of Southern California aeeredited vivaria. All dogs had normal
!JllOLOGY / JANUARY 1991 /
blood work (ereatinine, BUN, and serum electrolytes), intravenous urograms, and nonrefluxing cystograms prior to surgery. Preoperatively the animals were placed on a liquid diet for forty-eight hours, and they were given oral cathartics and oral neomycin and erythromycin base the day prior to surgery. The surgery was performed under routine sterile conditions with sodium pentothal anesthesia, and the dogs were maintained on intravenous fluids both during and following the procedure. A midline transperitoneal incision was used. The right ureter was isolated, ligated, and transected near the urinary bladder. The left ureter was left intact into the bladder to serve as a control. Both kidneys were examined and wedge specimens were obtained for biopsy to check for pre-existing renal disease. A 42-cm loop of ileum was isolated 15 cm above the ileocecal valve and the mesentery and bowel divided (Fig. 1). The loop was marked off with silk sutures leaving 15 cm for the afferent limb, 12 cm for each limb of the reservoir, and 3 cm for the efferent stub. The two ends of the loop were dosed with either a TA-30 Premium intestinal stapler (4.8 size staples) or with our standard Parker-Kerr 3-0 chromic suture. The bowel continuity was reestablished with a standard two-layer silk end-to-end anastomosis. The segment of isolated ileum was laid out in a "U" shape with the apex of the "U" directed cephalad. The limbs of the reservoir were sewn
VOLUME XXXVII, NUMBER 1
81
on••<•ef ferent limb oversewn ~ /
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t x4t'
,
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limb ,, ,.., closed !t{d.~![; -
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?[(;unE 2. Limbs oJ reservoir are directed cephatad and sutured together near mesenteric border. Reservoir then opened and back wall closed.
cystoplasty.
i-:L:i,L ' ,.""',"2/
'I', 2"A
'C-%
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affer;nt limb nipple inversion
Fmu}~E 3. Nipple valve is created by intussuscepting afferent limb with All~ clamps after mesentery beneath limb has been stripped ]or 7 cm. Marlex strip is located at base of nipple. Valve is stabilized by application oj three rows of staples from TA-55 stapler.
together near the mesentery with a running 3-0 polyglycolie acid suture, and the reservoir was opened with the eautery knife (Fig. 2). The incised mucosa of the back wall of the reservoir was oversewn with two layers of running 3-0 polyglycolic acid suture. The mesentery underlying the portion of the afferent limb to be intussuscepted was then in82
cised. A 7-cm window in the mesentery at ft. base of the afferent limb was created bv divk ing the mesentery with the cautery knife. A 2.5 em strip of Marlex was passed through a sep~ rate window of Deaver just beyond the strippe mesentery leaving one vascular arcade betwee them. Allis foreep clamps were then passed up ap proximately 4 em into the afferent limb ani used to grasp the inner wall and intussuscep the ileum into the reservoir ereating a nipp! valve which was 3.5 cm to 4 cm long (Fig. 3i Three rows of staples were applied to the ni~ ple, extending up to the base of the Marlex. TA-55 stapler was used, utilizing two rows c 4.8 size metal and one row of Polvsorb Lacti mer absorbable staples (United States Surgici Corporation) A finger was passed through th completed nipple valve, and the Marlex stri:, was sewn circumferentially around the base~ the nipple with 2-0 nylon interrupted suture The Marlex collar was fixed both to the rese~ voir and to the afferent limb. )] The hemi-Koek reservoir was then partial!~ closed with two layers of running 3-0 polvgl)~] eolie acid suture (Fig. 4). This formed a "goO t cup patch for the subsequent enteroeystoplastN
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/ JANUARY 1991 ;
VOLUME XXXVII, NUMBEIti
TABLE I. Dog No. 1 (F) 2 (F) 3 (F) 4 (M) 5(M) 6 (M) 7 (M) , :8 (F) '9 (F) i10 (F) ~:~: ::ii (F) ~i : i:i12 (F) : ! 3 (F) ;14 (F) ,:: 15 (F) ':(
Postoperative Course (Length) Uncomplicated (17 mos) Uncomplicated (16 mos) Died, urine leak (8 days) Died, peritonitis (14 mos) Died, urine leak (14 days) Died, urine leak (13 days) Died, urinc leak (9 days) Uncomplicated (12 mos) Uncomplicated (12 mos) Died, urine leak (7 days) Uncomplicated (20 mos) Uncomplicated (24 mos) Uncomplicated (24 mos) Uncomplicated (30 mos) Uncomplicated (36 mos)
Postoperative course and findings at time of autopsy
Reflux
Valve Length (cm)
Calculi
Creatinine
Chronic Pyelonephritis
None
2.5
Multiple
2.2
Marked
None
2.5
Multiple
0.9
None
. .
2.8
.
None
2.7
Multiple
. .
2.5
.
.
.
.
.
.
. .
2.6
.
.
.
.
.
.
. .
3.0
.
.
.
.
.
.
None
2.8
Multiple
0.8
Moderate
None
3.0
None
1.1
None
. .
3.0
.
None
2.8
Multiple
1.0
None
None
3.0
Multiple
0.8
None
None
3.0
Multiple
1.0
Mild
None
3.2
Multiple
0.9
None
None
3.0
Multiple
0.8
None
i:Thei~right ureter was spatulated and anasto!~osed end-to-side to the r e m a i n i n g afferent i~limb using i n t e r r u p t e d 4-0 polyglycolic acid suture. A partial cystectomy was p e r f o r m e d (api~roximately 30 % of the b l a d d e r removed), and !the hemi-Kock reservoir was flipped d o w n and '!~i[fiastomosed to the opening in the back wall of :!}he bladder w i t h t w o layers of r u n n i n g 3-0 ~i~blyglycolic acid suture. A suprapubic cystos,::t~rav •catheter (20-F Folev~ was olaced in most ; f the dogs, and a urethral catheter (20-F Fo~:lgi') was also inserted in all female dogs. It was !fOund to be too difficult and t r a u m a t i z i n g to i}iace a sizeable urethral catheter in the males. !~Aone2inch Penrose drain was placed at the base !b! the surgical field and b r o u g h t out t h r o u g h a :,,separate stab w o u n d . T h e a b d o m e n was well iirtigated with antibiotic solution and closed in iiayers. , ne ;,:!Postoperativeb, the do~s were maintai d on :l,ntravenous fluicts a n d a n t i b i o t i c s (penicillin
!---'J~OEyi~~i
.
.
.
.
.
.
. .
.
.
None
.
.
and gentamicin) for a m i n i m u m of five days under strict veterinary care. T h e y were normally begun on a diet a n d h a d their catheters rem o v e d on day 5. T h e Penrose drain was rem o v e d on the following day. Once fully recovered, the dogs were returned to their routine chronic care in the vivaria. Any febrile episodes were treated w i t h antibiotics. T h e surviving dogs were followed for a total of twelve to thirty-six m o n t h s . Prior to sacrifice, blood chemistries were obtained as were cystograms and intravenous urograms. At autopsy the entire urinary systems (kidneys, ureters, hemiKock reservoirs, and bladders) were r e m o v e d intact for histopathologic examination. Results All dogs survived the surgery and initially did well (Table I). Five dogs, however, died the second week postoperatively, of complications
JANUARY 1991 ,' VOLUME XXXVII, NUMBER 1
83
FmURE 5. Studies in chronic dogs just prior to autopsy. (A) Scout fihn wi~tt metal staples visible in 3-cm~ nipple valve (above catheter tip). (B) Cystogram revealing no reflux. (C) 1~ P with well-preserved kidneys~ and upper tracts prior to autopsy.. :~
secondary to urine leakage and pelvic abscess. Of the four males, three died of early complications secondary to plugging of their urethra with mucus and debris and difficulty maintaining their suprapubie catheters. A leak along the anastomosis or at the suprapubic tube site developed. After our initial difficulty in maintaining urine drainage in male dogs, only female dogs were used with improved results. Autopsies were performed on all five dogs that died in the postoperative period, and in every instance the nipple valve was intact and the ureteral anastomosis was healing well. Ten dogs survived and were able to be followed long term. All did well, regained their weight and beeame as aetive as they were prior to surgery. They were maintained at the vivaria under proper veterinary eare. Any febrile episodes were treated with antibioties though there was no evidence of any chronic illnesses in any of the dogs. The dogs were studied with blood work and x-ray examinations and were saerificed with sodium pentothal and autopsies performed twelve to thirty-six months postoperatively. The lone chronic male (dog 4) died
84
prior to its planned studies after surviving fourteen months. He had suddenly stopped urinating just before his death and at autopsy wasl found to have urinary ascites, an extremely dis;i tended bladder that was leaking urine, and ~'~ large calculus occluding his urethra. On clos~ inspection, there were multiple calculi loeated! on the exposed metal staples near the tip of the nipple valve. The nipple valve was 2.7 cm lon and was in otherwise excellent condition. There was no evidence of reflux, a dilated afferen limb, or chronic pyelonephritis either grossly o~ histologically. Both kidneys weighed approxi: mately 60 g. Prior to sacrifice, the nine surviving female dogs had serum chemistries (SMA-6 and SMA~ 1"2) checked and had a gravity eystogram and intravenous pyelogram performed (Fig. 5). The eystograms were performed with the c0ntras{ material suspended at 80 cm and at least 400 c~ were instilled. There was no evidence of reflu,! on any of the cystograms. Three dogs (1, 8, 13), however, had dilated right ureters and smaller scarred right kidneys. All blood values were normal except for ereatinine of 9,.2 in one dog (1).!
UROLOGY
/ JANUARY 1991 ,' VOLUME XXXVII, NUMBEtt~t
FIc~R:~;6. (A) Autopsy specimen of entire urinary system, Nipple valve shown protruding into opened hemi-Kock bladder. (B) Calculi formed on exposed metal staples near tip of valve and on eroded Marlex cuff at base of nipple.
Flocl~r: 7. Right and left kidneys after autopsy in chronic diverted dog without evidence of pyelonephritis.
:,i:iAt autopsy the entire urinary system was ex:itiiriined (Fig. 6A). Multiple ealeuli were found "..onthe valves of 7 of the 9 dogs (Fig. 6B). The ~ialves appeared to be healthy and well healed !{length 2.5 em to 3.2 cm) despite the removal of ,'the underlying mesenterv, The calculi were loic~ated predominantly on "the exposed metal sta'iples at the ends of the valves. In 5 of the dogs, ~,,Caleuliwere found at a point where the Marlex !}:011athad eroded into the reservoir. The small ':areas of erosion were usually located where the i:;Marlex was included in a metal staple line or )!~here a Marlex nylon tacking suture had been :'~laeed through the reservoir wall. Calculi also ifgtmed on metal staples that were exposed at {he dosed end of the afferent limb. All metal ~taples in the bottom two thirds of the nipple i~:alveswere routinely well covered with mucosa ghd were stone free. The absorbable staple lines :.!!ealedwell with good fibrosis of the inner walls i!Bfthe valves and were never the nidus for stone i!0rmation.
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JANUARY 1991
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The diverted right kidneys in 7 of these dogs showed no histologic changes and specifically no evidence of chronic pyelonephritis and grossly weighed the same as their counterparts (Fig. 7). The other 3 right kidneys exhibited some degree of hydronephrosis and chronic pyelonephritie scarring and were from dogs with dilated ureters secondary to ureteral ileal stenosis and concurrently had calculus formation on staples in their afferent limbs. None of these dogs had evidence of dilation of the afferent limbs which one would expect with reflux or valve obstruction. Comment What arc the goals of the ideal urinary diversion? Obviously, one would like the diversion to mimic the native urinary bladder. It should be able to effectively collect and store urine without reflux, absorption, or infeetion problems and permit emptying under voluntary
VOI,UME XXXVII, NUMBER 1
85
control. ~Ib this end, urologic surgeons have sought to perfect the internally continent, nonrefluxing urinary diversion for more than a century. Entering the 1980s, however, the most frequently used form of diversion has been the refluxing ileal conduit with an external collecting appliance. Tried but generally discarded have been the ureterosigmoidostomy and attempts by Bricker and Eiseman ~ and Gilchrist e t al. ~2 to utilize the ileocecal segment for continence. In the face of this, the Kock continent ileal reservoir appears to be one of the most innovative advances in the field of urology, to date. Its function hinges on the creation and maintenance of two separate nipple valves to insure continence and prevent reflux. According to the work of Kock 2 and Leisinger e t a l . , ~° these valves that are created by intussuscepting suitable lengths of ileum need to have an effective nipple length of at least 2.0 cm to 2.5 cm to be functional. The principle of an intussuscepted valve is not new. It was described as early as 1899 by WatsujP 3 in constructing a leak-proof gastrostom3: Various surgeons have since applied the technique to fit a variety of circumstances in the urinary tract, including Basso in 1951, ~4 Smith and Hinman in 1955, ~5 Turnbull and Higgins in 1957, ~6 and Turner and Goodwin in 1959. ~7 These intussusception procedures, however, were never consistently applied and maintained in a large clinical series. The valves were difficult to keep competent. Kock continued to modify and refine the intussuscepted nipple valve until it was clinically reproducible. He added an anchoring Marlex collar or fascial strip to the base of the valve and further stapled the nipple with four rows of metal staples. Still, in his original series of 12 patients, 8 needed additional surgery because of extussusception of the valves resulting in incontinence or reflux.; This was the only published series at the start of our study. It was thought that the slippage of the valves was secondary to tlm mass of the mesentery between the two walls of the nipple. In an effort to counteract this problem, a principle that Hendren ~8 had noted previously was tested in our study. He reported that up to 8 cm of mesentery could be stripped from the ileum without loss of viability. In our animals, mesentery attached to the portion of the limb to be intussuscepted was divided for a distance of 7 cm. The resulting 3.5-cm nipples would ap-
86
pear to be somewhat dusky at surgery but were always h e a l t h y and intact at the time of autopsy. No nipple valve would have required revision. It is possible that up to ). cm of the terminal nipple may initially have sloughed off, but the ultimate valve length was never less than the needed 2.0 cm to 2.5 cm. Cystograrns revealed no evidence of reflux in any of the dogs. In dogs without ureteral ileal stenosis i there was no evidence of histologic changes in any of the diverted kidneys. The problem of calculus formation is a real one. Metal staples cannot be left exposed in this system. In our clinical series, an adjustment! was m a d e a f t e r c a l c u l u s f o r m a t i o n wa~ noted. ~9,2° The distal five staples are now re~! moved from the TA-55 stapler so that there arei no terminal staples in the nipple. The staples a~ the base of the nipple are the ones necessary t~ prevent extussusception, and these tend to gei~ buried beneath the mucosa. Marlex is too er~ sive a material to be safely used as an anchorini collar. Since this study, a less permanent an, less erosive material, polyglycolic acid mesh, i being used for the collar in humans. If one use the stapler to close the end of the afferent limb this staple line must also be oversewn because? the staples may become exposed and form.~ stones where they are impossible to be easily r ~ trieved. :,. The absorbable Polysorb Lactomer stapM were being tested for their usefulness in the res! ervoir and nipple construction. These stapld appeared to promote appropriate healing ant were never the nidus for calculi. The absorb able staples, however, are still s o m e w h a awkward to use. Appropriate-sized staplers uti~ lizing absorbable staples w o u l d definitel~ streamline the lengthy reservoir closure. T ~ application is important and needs further in~ vestigation. !; Conclusions :: The intussuscepted antirefluxing nipple valw appears to be a reproducible, viable, long-tern concept. This animal study and histopathologiq examination supports what we see radiograph icallv in our human series. Slippage of the nipi ple valve can be decreased by stripping the inel sentery from beneath the length of ileum to M~ intussuscepted while still maintaining a viabld valve. Metal staples can be used in the urinarl tract if none is left exposed above the mucosa. they are left exposed, especially at the tip of th! valve, calculi will form. Marlex is too erosive t~
UROLOGY
/ JANUARY 1991 ,' VOLUME XXXVII, NUMBEIti~..
be used as an anchoring collar, and other materials will need to be used. Pyelonephritis and upper tract changes will probably be minimal in continent Kock diversions especially if a noncompromised ureteral ileal anastomosis exists and calculi are eliminated. Absorbable staples may become increasingly important as the staplers and stapling technique evolve. 2025 Zonal Avenue, Suite GH5900 Los Angeles, California 90033 (DR. BOYD) AcKNOWLEDGMENq; To United States Surgical Corporation for f u n d i n g this project and supplying the investigative absorbable staples; Peter Nichols, M.D., who performed the histopathologie examination; Sergiu Melinte, D.V.M., who provided veterinary support; and Ella Skinnet, M.D., a n d C u r t N. Tsujimoto, M.D., who assisted With the surgery. References ..d. Kock NG, et at: Urinary diversion via a continent ileal reserVoir: clinical results in 12 patients, J Urol 128:469 (1982). .'2. Koek NG: Ileostomy without external appliance. A survey :'0f 25 patients provided with intestinal reservoir, Ann Surg 173: v545 (1971). Kock NG, et al: Changes in renal parenchyma and the up,per urinary tracts following urinary diversion via a continent urinary diversion: an experimental study in dogs, Scand J Urol Nephrol (8uppl) 49:11 (1978). ~i~.114. Kock NG, et al: Urinary diversion via a continent ileum rcs:ei!,oir: clinical experience, Seand J Urol Nephrol (Suppl) 49:23 ~'(1978). i 5. Jagen'mrg J, Kock NG, Norlen L, and Trasti H: Clinical
significance of changes in composition of urine during collection and storage in continent ileum reservoir urinary diversion, Seand J Urol Nephrol (8uppl) 49:43 (1978). 6. Norlen L, and 'I1"asti H: Functional behavior of the continent ileum reservoir for urinary diversion: an experimental elinie',fl study; Seand J Urol Nephrol (Suppl) 49:33 (1978). 7. Trasti H: Urinary diversion via a continent ileum reservoir, Stand J Urol Nephrol (Suppl) 49" 5 (1978). 8. Koek NG: Evolution of ileostomy surgery, Can J Surg 24: 270 (1981). 9. Gerber A, Apt MK, and Craig PH: The Kock continent ileostom~,; Surg Gynecol Obstet 156:345 (1983). 10. Leisinger HJ, Schauwecher H, and Sauberli It: Dynamics of the continent ileal bladder: an experimental study in dogs, Invest Urol 15:49 (1977). 11. Bricker E, and Eiseman B: Bladder reconstruction from cecum and ascending colon following resection of pelvic viscera, Ann Surg 132:77 (1950). 12. Gilchrist RK, Merricks JW, Hamlin MH, and Rieger IT: Construction of substitute bladder and urethra, Surg Gyneeol Obstet 90:752 (1950). 13. Watsuji H: Eine Kobinierte Anwendung des Itackers und Funtanschen verfahrens bet der Gastrostomie, Mitt Med Geseltach (Tokyo) 13:879 (1899). 14. Basso DE: The efficacy and applicability of an intussuscepted conical valve in preventing regurgitation and leakage of intestinal contents, Ann Surg 133:477 (1951). 15. Smith GI, and Hinman F Jr: The intussuscepted ileal cystostomy, J Urol 73:261 (1955). 16. Turnbull RB Jr, and Higgins CC: Ileal valve pouch for urinary tract diversion, Cleve Clin Q 24:187 (1957). 17. qhrner RD, and Goodwin WE: Experiments with intussuscepted ileal valves in ureter',d substitution, J Urol 31:526 (1959). 18. Hendren WH: Reoperative ureteral reimplantations: management of the difficult case, J Pediatr Surg 15:1770 (1980). 19. Skinner DG, Lieskovsky G, and Boyd SD: "l~chnique of creation of a continent internal ileal reservoir (Kock pouch) for urinary diversion, Urol Clin North Am 11:741 (1984). 20. Skinner DG, Boyd SD, and Lieskovsky G: Clinical experience with the Kock continent ileal reservoir for urinary diversion, J Urol 132:1101 (1984).
;UI~.DLOGY / JANUARY 1991 ," VOLUME XXXVII, NUMBER 1
87
KOCK ILEAL URINARY RESERVOIR Experimental Investigation in Dogs MARK H. KAWACHI, M.D. THOMAS E. AHLERING, M.D.
STUART D. BOYD, M.D. DONALD G. SKINNER, M.D. GARY LIESKOVSKY, M.D.
From the Division of Urology; University of Southern California School of Medicine, Los Angeles, California
ABSTRACT--To better assess the construction, maintenance, and function of the Kock ileali urinary reservoir with its continent antirefluxing nipple valves, laboratory investigations in dog~I were done simultaneously with clinical trials in humans in 1983. Fifteen dogs underwent creatio~i of hemi-Kock ileal reservoirs (without the efferent valve and limb) that were anastomosed to thei~i bladders as enterocystoplasties. The afferent antirefluxing nipple valves were intussuscepted after cm of underlying mesentery had been removed. The nipples were further stabilized with metal an~~:' absorbable (Polysorb) staples and Marlex collars. The right ureters were anastomosed to the af ferent limb of the reservoirs with the contralateral systems left intact as controls. Ten dogs were ab~ to be followed at the vivaria for twelve to thirty-six months and then studied. All nipple valv~ remained intact, viable, and nonrefluxing without revision. All kidneys remained histologicall normal except those in dogs with dilated ureters secondary to ureteroileal stenosis with concurren calculi formation. Calculi formed on exposed metal staples and Marlex. The absorbable stapl~ were found to promote appropriate healing and were never the nidus for stone formation. It ap: pears that the int~n~S;scepted mpplevalv~ (wzth its mesentery removed) is reproducible and fu tionally reliable in p eventing eft x. t also appears these valves can histologically p r e s e ~ diverted kidneys if the upper u~inary tract drainage is normal and calculi are minimized. T ~ proper placement of taples a d the elimination of Marlex-anchoring collars are indicated ta! minimize calculi, i!!
In 1982, Koek and associates ~ first published in the United States their experience with the continent ileal urinary reselwoir. This major contribution to urology represented more than ten years of experimental and clinical study. ~° Their approach combined and adapted many older ideas with several new techniques and opened the door to a classic advance in urologic surgery. It was specifically this work that prompted our own investigations and clinical trials into the continent urinary diversion.
80
The most important factor in the success 01 the Koek ileal urinary reservoir is the creati6~ and maintenance of nipple valves to prevent re flux and insure continence. Both Kock~ an~ Leisinger, Sehauweeher, and Sauberli TM h~i published short-term animal studies of thN valves that were extremely important in e s t ~ lishing their efficacy. While they had s h o ~ that the valves could be made to work, h ~ ever, the revision rate and potential c ~ plication of the valves were high T h e r e f ~
UROLOGY / JANUARY1991 / VOLUME XXXVII, NL;MBE~1
1,.
!......e/' {(
' ...%
I
15cm afferent limb
./
12cm reservoir portion
y 3cm efferent limb
FmURE 1. F o r t y - t w o cm loop o_f ileum is isolated and appropriate limb lengths marked.
12 cm reservoir portion ;~simultaneous to beginning our own clinical itrials in 1982 with the ileal urinary reservoir in humans, laboratory experiments were begun to 'further study the continent nipple valves. Our goals prior to the study were to create a ilpermanent nipple valve and to investigate the imaterials and methods that would minimize t h e problems associated with this valve's conStruction and function. Specifically we wanted to investigate the use of staples, both metal and ::.!absorbable type staples (Polysorb), and ex~amine their concomitant problems with stone formation in the urinary tract, look at the )Marlex fixation collars at the base of the valves, ..:',study the viability of the nipple if the underly:i!ng mesentery was removed prior to intussusception, and most important study the long:{erm effects of the valves on the kidneys and upper urinary tracts. ~:" To this end, h e m i - K o e k ileal reservoirs ::i(without the efferent valves and limbs) were ;created in dogs and anastomosed to the bladder ,as an enteroeystoplasty, The dogs were followed !for twelve to thirty-six months and studied. i;
Material and Methods :Between January, 1983, and January, 1984, ~!5 adult mongrel dogs (11 females and 4 males), :}'eighing between 24 and 30 kg, were prepared iand operated on using the same standardized technique at a University of Southern California aeeredited vivaria. All dogs had normal
!JllOLOGY / JANUARY 1991 /
blood work (ereatinine, BUN, and serum electrolytes), intravenous urograms, and nonrefluxing cystograms prior to surgery. Preoperatively the animals were placed on a liquid diet for forty-eight hours, and they were given oral cathartics and oral neomycin and erythromycin base the day prior to surgery. The surgery was performed under routine sterile conditions with sodium pentothal anesthesia, and the dogs were maintained on intravenous fluids both during and following the procedure. A midline transperitoneal incision was used. The right ureter was isolated, ligated, and transected near the urinary bladder. The left ureter was left intact into the bladder to serve as a control. Both kidneys were examined and wedge specimens were obtained for biopsy to check for pre-existing renal disease. A 42-cm loop of ileum was isolated 15 cm above the ileocecal valve and the mesentery and bowel divided (Fig. 1). The loop was marked off with silk sutures leaving 15 cm for the afferent limb, 12 cm for each limb of the reservoir, and 3 cm for the efferent stub. The two ends of the loop were dosed with either a TA-30 Premium intestinal stapler (4.8 size staples) or with our standard Parker-Kerr 3-0 chromic suture. The bowel continuity was reestablished with a standard two-layer silk end-to-end anastomosis. The segment of isolated ileum was laid out in a "U" shape with the apex of the "U" directed cephalad. The limbs of the reservoir were sewn
VOLUME XXXVII, NUMBER 1
81
on••<•ef ferent limb oversewn ~ /
/
t x4t'
,
,,
limb ,, ,.., closed !t{d.~![; -
'
-
:%
%\ YN'%
.7
; I
/'
( - ---~
\ ' ~
~
-
"---
"
,
'"".. ~ i ,", ~ !
?[(;unE 2. Limbs oJ reservoir are directed cephatad and sutured together near mesenteric border. Reservoir then opened and back wall closed.
cystoplasty.
i-:L:i,L ' ,.""',"2/
'I', 2"A
'C-%
% •
affer;nt limb nipple inversion
Fmu}~E 3. Nipple valve is created by intussuscepting afferent limb with All~ clamps after mesentery beneath limb has been stripped ]or 7 cm. Marlex strip is located at base of nipple. Valve is stabilized by application oj three rows of staples from TA-55 stapler.
together near the mesentery with a running 3-0 polyglycolie acid suture, and the reservoir was opened with the eautery knife (Fig. 2). The incised mucosa of the back wall of the reservoir was oversewn with two layers of running 3-0 polyglycolic acid suture. The mesentery underlying the portion of the afferent limb to be intussuscepted was then in82
cised. A 7-cm window in the mesentery at ft. base of the afferent limb was created bv divk ing the mesentery with the cautery knife. A 2.5 em strip of Marlex was passed through a sep~ rate window of Deaver just beyond the strippe mesentery leaving one vascular arcade betwee them. Allis foreep clamps were then passed up ap proximately 4 em into the afferent limb ani used to grasp the inner wall and intussuscep the ileum into the reservoir ereating a nipp! valve which was 3.5 cm to 4 cm long (Fig. 3i Three rows of staples were applied to the ni~ ple, extending up to the base of the Marlex. TA-55 stapler was used, utilizing two rows c 4.8 size metal and one row of Polvsorb Lacti mer absorbable staples (United States Surgici Corporation) A finger was passed through th completed nipple valve, and the Marlex stri:, was sewn circumferentially around the base~ the nipple with 2-0 nylon interrupted suture The Marlex collar was fixed both to the rese~ voir and to the afferent limb. )] The hemi-Koek reservoir was then partial!~ closed with two layers of running 3-0 polvgl)~] eolie acid suture (Fig. 4). This formed a "goO t cup patch for the subsequent enteroeystoplastN
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VOLUME XXXVII, NUMBEIti
TABLE I. Dog No. 1 (F) 2 (F) 3 (F) 4 (M) 5(M) 6 (M) 7 (M) , :8 (F) '9 (F) i10 (F) ~:~: ::ii (F) ~i : i:i12 (F) : ! 3 (F) ;14 (F) ,:: 15 (F) ':(
Postoperative Course (Length) Uncomplicated (17 mos) Uncomplicated (16 mos) Died, urine leak (8 days) Died, peritonitis (14 mos) Died, urine leak (14 days) Died, urine leak (13 days) Died, urinc leak (9 days) Uncomplicated (12 mos) Uncomplicated (12 mos) Died, urine leak (7 days) Uncomplicated (20 mos) Uncomplicated (24 mos) Uncomplicated (24 mos) Uncomplicated (30 mos) Uncomplicated (36 mos)
Postoperative course and findings at time of autopsy
Reflux
Valve Length (cm)
Calculi
Creatinine
Chronic Pyelonephritis
None
2.5
Multiple
2.2
Marked
None
2.5
Multiple
0.9
None
. .
2.8
.
None
2.7
Multiple
. .
2.5
.
.
.
.
.
.
. .
2.6
.
.
.
.
.
.
. .
3.0
.
.
.
.
.
.
None
2.8
Multiple
0.8
Moderate
None
3.0
None
1.1
None
. .
3.0
.
None
2.8
Multiple
1.0
None
None
3.0
Multiple
0.8
None
None
3.0
Multiple
1.0
Mild
None
3.2
Multiple
0.9
None
None
3.0
Multiple
0.8
None
i:Thei~right ureter was spatulated and anasto!~osed end-to-side to the r e m a i n i n g afferent i~limb using i n t e r r u p t e d 4-0 polyglycolic acid suture. A partial cystectomy was p e r f o r m e d (api~roximately 30 % of the b l a d d e r removed), and !the hemi-Kock reservoir was flipped d o w n and '!~i[fiastomosed to the opening in the back wall of :!}he bladder w i t h t w o layers of r u n n i n g 3-0 ~i~blyglycolic acid suture. A suprapubic cystos,::t~rav •catheter (20-F Folev~ was olaced in most ; f the dogs, and a urethral catheter (20-F Fo~:lgi') was also inserted in all female dogs. It was !fOund to be too difficult and t r a u m a t i z i n g to i}iace a sizeable urethral catheter in the males. !~Aone2inch Penrose drain was placed at the base !b! the surgical field and b r o u g h t out t h r o u g h a :,,separate stab w o u n d . T h e a b d o m e n was well iirtigated with antibiotic solution and closed in iiayers. , ne ;,:!Postoperativeb, the do~s were maintai d on :l,ntravenous fluicts a n d a n t i b i o t i c s (penicillin
!---'J~OEyi~~i
.
.
.
.
.
.
. .
.
.
None
.
.
and gentamicin) for a m i n i m u m of five days under strict veterinary care. T h e y were normally begun on a diet a n d h a d their catheters rem o v e d on day 5. T h e Penrose drain was rem o v e d on the following day. Once fully recovered, the dogs were returned to their routine chronic care in the vivaria. Any febrile episodes were treated w i t h antibiotics. T h e surviving dogs were followed for a total of twelve to thirty-six m o n t h s . Prior to sacrifice, blood chemistries were obtained as were cystograms and intravenous urograms. At autopsy the entire urinary systems (kidneys, ureters, hemiKock reservoirs, and bladders) were r e m o v e d intact for histopathologic examination. Results All dogs survived the surgery and initially did well (Table I). Five dogs, however, died the second week postoperatively, of complications
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FmURE 5. Studies in chronic dogs just prior to autopsy. (A) Scout fihn wi~tt metal staples visible in 3-cm~ nipple valve (above catheter tip). (B) Cystogram revealing no reflux. (C) 1~ P with well-preserved kidneys~ and upper tracts prior to autopsy.. :~
secondary to urine leakage and pelvic abscess. Of the four males, three died of early complications secondary to plugging of their urethra with mucus and debris and difficulty maintaining their suprapubie catheters. A leak along the anastomosis or at the suprapubic tube site developed. After our initial difficulty in maintaining urine drainage in male dogs, only female dogs were used with improved results. Autopsies were performed on all five dogs that died in the postoperative period, and in every instance the nipple valve was intact and the ureteral anastomosis was healing well. Ten dogs survived and were able to be followed long term. All did well, regained their weight and beeame as aetive as they were prior to surgery. They were maintained at the vivaria under proper veterinary eare. Any febrile episodes were treated with antibioties though there was no evidence of any chronic illnesses in any of the dogs. The dogs were studied with blood work and x-ray examinations and were saerificed with sodium pentothal and autopsies performed twelve to thirty-six months postoperatively. The lone chronic male (dog 4) died
84
prior to its planned studies after surviving fourteen months. He had suddenly stopped urinating just before his death and at autopsy wasl found to have urinary ascites, an extremely dis;i tended bladder that was leaking urine, and ~'~ large calculus occluding his urethra. On clos~ inspection, there were multiple calculi loeated! on the exposed metal staples near the tip of the nipple valve. The nipple valve was 2.7 cm lon and was in otherwise excellent condition. There was no evidence of reflux, a dilated afferen limb, or chronic pyelonephritis either grossly o~ histologically. Both kidneys weighed approxi: mately 60 g. Prior to sacrifice, the nine surviving female dogs had serum chemistries (SMA-6 and SMA~ 1"2) checked and had a gravity eystogram and intravenous pyelogram performed (Fig. 5). The eystograms were performed with the c0ntras{ material suspended at 80 cm and at least 400 c~ were instilled. There was no evidence of reflu,! on any of the cystograms. Three dogs (1, 8, 13), however, had dilated right ureters and smaller scarred right kidneys. All blood values were normal except for ereatinine of 9,.2 in one dog (1).!
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/ JANUARY 1991 ,' VOLUME XXXVII, NUMBEtt~t
FIc~R:~;6. (A) Autopsy specimen of entire urinary system, Nipple valve shown protruding into opened hemi-Kock bladder. (B) Calculi formed on exposed metal staples near tip of valve and on eroded Marlex cuff at base of nipple.
Flocl~r: 7. Right and left kidneys after autopsy in chronic diverted dog without evidence of pyelonephritis.
:,i:iAt autopsy the entire urinary system was ex:itiiriined (Fig. 6A). Multiple ealeuli were found "..onthe valves of 7 of the 9 dogs (Fig. 6B). The ~ialves appeared to be healthy and well healed !{length 2.5 em to 3.2 cm) despite the removal of ,'the underlying mesenterv, The calculi were loic~ated predominantly on "the exposed metal sta'iples at the ends of the valves. In 5 of the dogs, ~,,Caleuliwere found at a point where the Marlex !}:011athad eroded into the reservoir. The small ':areas of erosion were usually located where the i:;Marlex was included in a metal staple line or )!~here a Marlex nylon tacking suture had been :'~laeed through the reservoir wall. Calculi also ifgtmed on metal staples that were exposed at {he dosed end of the afferent limb. All metal ~taples in the bottom two thirds of the nipple i~:alveswere routinely well covered with mucosa ghd were stone free. The absorbable staple lines :.!!ealedwell with good fibrosis of the inner walls i!Bfthe valves and were never the nidus for stone i!0rmation.
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JANUARY 1991
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The diverted right kidneys in 7 of these dogs showed no histologic changes and specifically no evidence of chronic pyelonephritis and grossly weighed the same as their counterparts (Fig. 7). The other 3 right kidneys exhibited some degree of hydronephrosis and chronic pyelonephritie scarring and were from dogs with dilated ureters secondary to ureteral ileal stenosis and concurrently had calculus formation on staples in their afferent limbs. None of these dogs had evidence of dilation of the afferent limbs which one would expect with reflux or valve obstruction. Comment What arc the goals of the ideal urinary diversion? Obviously, one would like the diversion to mimic the native urinary bladder. It should be able to effectively collect and store urine without reflux, absorption, or infeetion problems and permit emptying under voluntary
VOI,UME XXXVII, NUMBER 1
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control. ~Ib this end, urologic surgeons have sought to perfect the internally continent, nonrefluxing urinary diversion for more than a century. Entering the 1980s, however, the most frequently used form of diversion has been the refluxing ileal conduit with an external collecting appliance. Tried but generally discarded have been the ureterosigmoidostomy and attempts by Bricker and Eiseman ~ and Gilchrist e t al. ~2 to utilize the ileocecal segment for continence. In the face of this, the Kock continent ileal reservoir appears to be one of the most innovative advances in the field of urology, to date. Its function hinges on the creation and maintenance of two separate nipple valves to insure continence and prevent reflux. According to the work of Kock 2 and Leisinger e t a l . , ~° these valves that are created by intussuscepting suitable lengths of ileum need to have an effective nipple length of at least 2.0 cm to 2.5 cm to be functional. The principle of an intussuscepted valve is not new. It was described as early as 1899 by WatsujP 3 in constructing a leak-proof gastrostom3: Various surgeons have since applied the technique to fit a variety of circumstances in the urinary tract, including Basso in 1951, ~4 Smith and Hinman in 1955, ~5 Turnbull and Higgins in 1957, ~6 and Turner and Goodwin in 1959. ~7 These intussusception procedures, however, were never consistently applied and maintained in a large clinical series. The valves were difficult to keep competent. Kock continued to modify and refine the intussuscepted nipple valve until it was clinically reproducible. He added an anchoring Marlex collar or fascial strip to the base of the valve and further stapled the nipple with four rows of metal staples. Still, in his original series of 12 patients, 8 needed additional surgery because of extussusception of the valves resulting in incontinence or reflux.; This was the only published series at the start of our study. It was thought that the slippage of the valves was secondary to tlm mass of the mesentery between the two walls of the nipple. In an effort to counteract this problem, a principle that Hendren ~8 had noted previously was tested in our study. He reported that up to 8 cm of mesentery could be stripped from the ileum without loss of viability. In our animals, mesentery attached to the portion of the limb to be intussuscepted was divided for a distance of 7 cm. The resulting 3.5-cm nipples would ap-
86
pear to be somewhat dusky at surgery but were always h e a l t h y and intact at the time of autopsy. No nipple valve would have required revision. It is possible that up to ). cm of the terminal nipple may initially have sloughed off, but the ultimate valve length was never less than the needed 2.0 cm to 2.5 cm. Cystograrns revealed no evidence of reflux in any of the dogs. In dogs without ureteral ileal stenosis i there was no evidence of histologic changes in any of the diverted kidneys. The problem of calculus formation is a real one. Metal staples cannot be left exposed in this system. In our clinical series, an adjustment! was m a d e a f t e r c a l c u l u s f o r m a t i o n wa~ noted. ~9,2° The distal five staples are now re~! moved from the TA-55 stapler so that there arei no terminal staples in the nipple. The staples a~ the base of the nipple are the ones necessary t~ prevent extussusception, and these tend to gei~ buried beneath the mucosa. Marlex is too er~ sive a material to be safely used as an anchorini collar. Since this study, a less permanent an, less erosive material, polyglycolic acid mesh, i being used for the collar in humans. If one use the stapler to close the end of the afferent limb this staple line must also be oversewn because? the staples may become exposed and form.~ stones where they are impossible to be easily r ~ trieved. :,. The absorbable Polysorb Lactomer stapM were being tested for their usefulness in the res! ervoir and nipple construction. These stapld appeared to promote appropriate healing ant were never the nidus for calculi. The absorb able staples, however, are still s o m e w h a awkward to use. Appropriate-sized staplers uti~ lizing absorbable staples w o u l d definitel~ streamline the lengthy reservoir closure. T ~ application is important and needs further in~ vestigation. !; Conclusions :: The intussuscepted antirefluxing nipple valw appears to be a reproducible, viable, long-tern concept. This animal study and histopathologiq examination supports what we see radiograph icallv in our human series. Slippage of the nipi ple valve can be decreased by stripping the inel sentery from beneath the length of ileum to M~ intussuscepted while still maintaining a viabld valve. Metal staples can be used in the urinarl tract if none is left exposed above the mucosa. they are left exposed, especially at the tip of th! valve, calculi will form. Marlex is too erosive t~
UROLOGY
/ JANUARY 1991 ,' VOLUME XXXVII, NUMBEIti~..
be used as an anchoring collar, and other materials will need to be used. Pyelonephritis and upper tract changes will probably be minimal in continent Kock diversions especially if a noncompromised ureteral ileal anastomosis exists and calculi are eliminated. Absorbable staples may become increasingly important as the staplers and stapling technique evolve. 2025 Zonal Avenue, Suite GH5900 Los Angeles, California 90033 (DR. BOYD) AcKNOWLEDGMENq; To United States Surgical Corporation for f u n d i n g this project and supplying the investigative absorbable staples; Peter Nichols, M.D., who performed the histopathologie examination; Sergiu Melinte, D.V.M., who provided veterinary support; and Ella Skinnet, M.D., a n d C u r t N. Tsujimoto, M.D., who assisted With the surgery. References ..d. Kock NG, et at: Urinary diversion via a continent ileal reserVoir: clinical results in 12 patients, J Urol 128:469 (1982). .'2. Koek NG: Ileostomy without external appliance. A survey :'0f 25 patients provided with intestinal reservoir, Ann Surg 173: v545 (1971). Kock NG, et al: Changes in renal parenchyma and the up,per urinary tracts following urinary diversion via a continent urinary diversion: an experimental study in dogs, Scand J Urol Nephrol (8uppl) 49:11 (1978). ~i~.114. Kock NG, et al: Urinary diversion via a continent ileum rcs:ei!,oir: clinical experience, Seand J Urol Nephrol (Suppl) 49:23 ~'(1978). i 5. Jagen'mrg J, Kock NG, Norlen L, and Trasti H: Clinical
significance of changes in composition of urine during collection and storage in continent ileum reservoir urinary diversion, Seand J Urol Nephrol (8uppl) 49:43 (1978). 6. Norlen L, and 'I1"asti H: Functional behavior of the continent ileum reservoir for urinary diversion: an experimental elinie',fl study; Seand J Urol Nephrol (Suppl) 49:33 (1978). 7. Trasti H: Urinary diversion via a continent ileum reservoir, Stand J Urol Nephrol (Suppl) 49" 5 (1978). 8. Koek NG: Evolution of ileostomy surgery, Can J Surg 24: 270 (1981). 9. Gerber A, Apt MK, and Craig PH: The Kock continent ileostom~,; Surg Gynecol Obstet 156:345 (1983). 10. Leisinger HJ, Schauwecher H, and Sauberli It: Dynamics of the continent ileal bladder: an experimental study in dogs, Invest Urol 15:49 (1977). 11. Bricker E, and Eiseman B: Bladder reconstruction from cecum and ascending colon following resection of pelvic viscera, Ann Surg 132:77 (1950). 12. Gilchrist RK, Merricks JW, Hamlin MH, and Rieger IT: Construction of substitute bladder and urethra, Surg Gyneeol Obstet 90:752 (1950). 13. Watsuji H: Eine Kobinierte Anwendung des Itackers und Funtanschen verfahrens bet der Gastrostomie, Mitt Med Geseltach (Tokyo) 13:879 (1899). 14. Basso DE: The efficacy and applicability of an intussuscepted conical valve in preventing regurgitation and leakage of intestinal contents, Ann Surg 133:477 (1951). 15. Smith GI, and Hinman F Jr: The intussuscepted ileal cystostomy, J Urol 73:261 (1955). 16. Turnbull RB Jr, and Higgins CC: Ileal valve pouch for urinary tract diversion, Cleve Clin Q 24:187 (1957). 17. qhrner RD, and Goodwin WE: Experiments with intussuscepted ileal valves in ureter',d substitution, J Urol 31:526 (1959). 18. Hendren WH: Reoperative ureteral reimplantations: management of the difficult case, J Pediatr Surg 15:1770 (1980). 19. Skinner DG, Lieskovsky G, and Boyd SD: "l~chnique of creation of a continent internal ileal reservoir (Kock pouch) for urinary diversion, Urol Clin North Am 11:741 (1984). 20. Skinner DG, Boyd SD, and Lieskovsky G: Clinical experience with the Kock continent ileal reservoir for urinary diversion, J Urol 132:1101 (1984).
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