Laparoscopic or laparoscopic-assisted cystopexy for pelvic bladder in 3 dogs

Abstract

The techniques and clinical outcomes of laparoscopic or laparoscopic-assisted cystopexy in 3 dogs diagnosed with pelvic bladder are reported herein.

The medical records of 2 dogs with pelvic bladder which underwent laparoscopic cystopexy, and 1 dog which underwent laparoscopic-assisted cystopexy were reviewed. Data retrieved included signalment, clinical signs, diagnostic imaging, surgical technique, and clinical outcome. Long-term follow-up was obtained by verbal interviews with owners.

Laparoscopic or laparoscopic-assisted cystopexy was successfully performed to reposition the urinary bladder within the abdominal cavity in all dogs. An intracorporeal suture technique was used in 2 dogs, whereas an extracorpreal technique was used in 1 dog. Two dogs with stranguria experienced complete resolution immediately following surgery and remained disease-free at 18 mo after cystopexy. A third dog with urinary incontinence subjectively improved (according to the owner) but had not resolved completely 2 d following surgery.

Key clinical message:

Laparoscopic or laparoscopic-assisted cystopexy may be an effective treatment for pelvic bladder in dogs and may offer a minimally invasive alternative to laparotomy. Male dogs with stranguria as the primary clinical sign may experience complete resolution following cystopexy.

Pelvic bladder, intrapelvic bladder, and caudally displaced urinary bladder are all terms used to describe conditions that result in caudal malposition of the urinary bladder. Pelvic bladder can result in urethral obstruction as well as urinary incontinence. Urethral obstruction is reported to occur secondary to urethral kinking and trigonal invagination (1,2), whereas urinary incontinence is secondary to a shortened functional urethral length, loss of exposure of the trigone to intra-abdominal pressure, and dysfunctional detrusor or urethral musculature (3,4). Pelvic bladder in dogs is rare, with most occurring in young, intact large-breed female dogs (3). However, it has also been reported in adult male dogs (2). The diagnosis of a pelvic bladder is typically made with contrast radiography and is characterized by at least 5% of the craniocaudal dimension of the bladder being present within the pelvic canal when fully distended (3). Cystopexy following repositioning of the urinary bladder in a normal, intra-abdominal location, is the treatment of choice and has been described via caudal laparotomy (1,2,5). Both laparoscopic and laparoscopic-assisted approaches to cystopexy have been reported in experimental models, but no clinical reports describing the clinical outcome in dogs with pelvic bladder exist (5,6). This report describes the laparoscopic techniques and clinical outcome of 3 dogs with pelvic bladder that underwent laparoscopic or laparoscopic-assisted cystopexy.

Electronic medical records of 2 hospitals (University of Florida College of Veterinary Medicine and University of California-Davis, School of Veterinary Medicine) between January 2012 and January 2021 were searched for dogs that had been diagnosed with a pelvic bladder and had subsequently undergone laparoscopic cystopexy.

Case descriptions

Dog #1

Clinical presentation

A 12-year-old male miniature poodle was referred to the University of Florida (UF) for a 2-week history of stranguria. The dog also had a history of chronic cough and had been diagnosed with chronic bronchitis and bronchiectasis, collapsing trachea, and mild mitral and tricuspid valve insufficiency. Urinalysis indicated 0 to 1 WBC/hpf, but an aerobic urine culture had no growth after 48 h. An abdominal ultrasound revealed a mildly thickened bladder wall with no evidence of calculi. A dynamic, contrast cystourethrogram revealed pelvic herniation of the urinary bladder neck and proximal urethra as well as urethral kinking (Figure 1). Bloodwork revealed a mild neutrophilia of 13.0 K/μL [reference range (RR): 3.0 to 9.9 K/μL], elevated BUN of 31 mg/dL (RR: 8 to 25 mg/dL), ALT of 195 U/L (RR: 22 to 68 U/L), AST of 73 U/L (RR: 15 to 52 U/L), and ALP of 221 U/L (RR: 8 to 114 U/L).

Figure 1.

A — Dynamic contrast cystourethrogram in Dog #1. B — Notice the extreme caudal pelvic displacement of the bladder, trigone, and proximal urethra following manual pressure on the abdomen. Notice the “S” shaped kink in the proximal urethra.

Laparoscopic-assisted cystopexy

The dog was prepared for surgery in routine, aseptic fashion. He was placed in dorsal recumbency on a surgical table (Durabuilt Medical, Texarkana, Arkansas, USA). The table was positioned to create slight (~15°) Trendelenburg position with right lateral obliquity. A 5.5-mm threaded cannula (Karl Storz Endoscopy-America, El Segundo, California, USA) was placed on ventral midline 1 cm caudal to the umbilicus routinely using a modified-Hasson technique. Capnoperitoneum was established using a mechanical insufflation unit to a maximum pressure of 10 mmHg. A 5-mm, 30° laparoscope (Karl Storz Endoscopy-America) was used to explore the caudal abdomen and pelvic canal. The urinary bladder was noted to be displaced caudally within the pelvic canal. A second, 5.5-mm threaded cannula was placed mid-distance between the umbilicus and pubic brim, in the left lateral abdomen. This location was selected based on caudal abdominal evaluation and was the proposed site of cystopexy. The urinary bladder was identified and grasped using 5-mm DeBakey forceps (Karl Storz Endoscopy-America), then repositioned within the abdominal cavity. Cranial tension on the urinary bladder was assessed to be minimal at the proposed site of cystopexy. The bladder was temporarily pexied to the peritoneal surface using 2 percutaneous stay sutures immediately caudal to the second cannula. The cannula was removed and capnoperitoneum discontinued. The second port incision was extended 3 cm caudally. The laparoscope was then removed. The craniolateral seromuscular layer of the urinary bladder was sutured to the transversus abdominus muscle using 3-0 PDS suture with 5 interrupted sutures in extracorporeal fashion. The surgical wound was closed and capnoperitoneum was re-established. The laparoscope was reinserted on midline to ensure that the bladder was positioned appropriately, and thereafter, the laparoscope and stay sutures were removed. The caudal umbilical cannula was removed, and the site closed in routine fashion. The procedure time was 78 min.

Outcome

The dog recovered from anesthesia and surgery without any apparent complications. He was bright, alert, and urinating normally the following day at which point he was discharged with instructions for activity restriction and for skin suture removal in 10 to 14 d. Treatment with meloxicam (0.11 mg/kg, PO, q24h for 3 d) was prescribed.

Two days after surgery, the owners reported that the dog appeared to be doing well and had been urinating normally. At 18 mo after surgery, the dog had not developed any subsequent episodes of straining to urinate.

Dog #2

Clinical presentation

A 2-year-old neutered male Yorkshire terrier was referred to the UF Small Animal Hospital for treatment of a pelvic bladder. The dog had a history of intermittent, severe stranguria over a 1.5-year interval. During these episodes, the dog was presented to his referring veterinarian who placed a urinary catheter to empty the bladder. A rectal examination at each visit revealed a palpable balloon-like structure within the pelvic canal. Abdominal radiographs and ultrasound were performed and revealed a pelvic bladder with no other abdominal abnormalities. Various treatments were initiated including amoxicillin-clavulanic acid (25.5 mg/kg, PO, q12h, for 2 wk) for potential urinary tract infection, Lactulose solution (272 mg/kg, PO, q8h for 5 d) as a stool softener, and grapiprant tablets (2 mg/kg, PO, q24h for 6 d) for pain control.

The dog also had a history of elevated ALT, ranging from 132 to 232 U/L (RR: 10 to 125 U/L), which normalized ~1 y later at 114 U/L. A protein C assay result was 66% (RR: 75 to 135%). Due to persistence of the dog’s stranguria and suspicion of a portosystemic shunt, the dog was referred for specialty surgical evaluation. A CT angiogram indicated no evidence of portosystemic shunting, but a pelvic urinary bladder was documented (Figure 2). A laparoscopic cystopexy was recommended to the owners who consented to the procedure.

Figure 2.

Computed tomography of the abdomen of Dog #2. The bladder is predominantly within the pelvic canal and there is dorsal kinking of the proximal urethra.

Laparoscopic cystopexy

The dog was prepared for surgery in routine, aseptic fashion. He was placed in dorsal recumbency on a surgical table. The table was positioned to create slight (~15°) Trendelenburg position with right lateral obliquity. Laparoscopic cystopexy was performed as described (6). Briefly, three 5.5-mm cannulas were placed: i) at ventral midline just caudal to the umbilicus; ii) ventral midline approximately 3 cm caudal to the first port; and iii) twice the lateral distance from the umbilicus to the abdominal nipple to the left and at the level of the first port. The urinary bladder was visualized within the pelvic canal (Figure 3 A). Laparoscopic DeBakey forceps were used to reposition the urinary bladder cranially along the left ventral aspect of the abdominal wall (Figure 3 B). A laparoscopic electrosurgical L-hook scalpel (Medtronic, Minneapolis, Minnesota, USA) was then used to scarify the urinary bladder and to make a 3-cm incision in the transversus abdominis muscle. The urinary bladder was then sutured to the transversus abdominis intracorporeally, in simple continuous fashion using 3-0 barbed suture (VLOC 180; Medtronic Minneapolis) (Figure 3 C). The bladder was then grasped at the apex for intracorporeal assessment of cystopexy adherence and it was filled with saline via a retrograde urinary catheter to assess for leakage. No leakage was observed, and the bladder was subsequently emptied. All ports were removed, and port sites closed in routine fashion. The procedure time was 77 min.

Figure 3.

Laparoscopic view of the intrapelvic bladder of Dog #2: A — before reposition; B — after reposition; and C — after completion of the cystopexy.

Outcome

At 6 d after surgery, the owners reported that the dog no longer strained to urinate. The dog developed polyuria and polydipsia post-operatively and was evaluated by the UF Internal Medicine service for neurologic issues 4 mo later. The PU/PD resolved later that month following discontinuation of furosemide and prednisone. At 1.5 y following his cystopexy the dog continues to urinate without straining and has not had any episodes of PU/PD.

Dog #3

Clinical presentation

A 3-year-old spayed female mixed breed dog was referred to the University of California-Davis for a 47-week history of urinary incontinence following ovariohysterectomy. The dog was able to urinate a full stream but would dribble urine in between voiding events. The dog’s physical examination was unremarkable. The dog had a complete blood (cell) count, serum biochemistry, urinalysis, urine culture, and abdominal ultrasound, with no clinically relevant abnormalities. A cystoscopy was subsequently performed and revealed a paramesonephric remnant that was laser ablated, and normal position of the ureteral papillae. A contrast cystourethrogram was performed and revealed a pelvic bladder. Laparoscopic cystopexy was performed as described earlier. The procedure time was 65 min.

Outcome

The dog recovered well and was discharged the day after the procedure. The dog was prescribed carprofen (2 mg/kg, q12h). The dog’s urinary continence was subjectively improved according to owner reports but had not completely resolved 2 d after surgery. Unfortunately, this dog was lost to follow-up in the short-term so no information beyond 2 d is available.

Discussion

Laparoscopic or laparoscopic-assisted treatment of pelvic bladder was performed with no surgical complications in 3 dogs. Although laparoscopic treatment of similar conditions (e.g., pelvic organ prolapse) is well-documented in human surgery, to the authors’ knowledge, there are no reports of laparoscopic treatment for pelvic bladder in the veterinary literature. In adult women, pelvic organ prolapse is a common condition involving the weakening of the pelvic floor muscles and ligaments leading to prolapse of 1 or more organs (bladder, uterus, or rectum) (7). This is generally an acquired condition due to various factors such as history of vaginal delivery, chronic cough, obesity, and menopause (8). Intrapelvic bladder in dogs has traditionally been regarded as congenital and a possible cause of urinary incontinence (9). However, recent reports have demonstrated urethral kinking and dysuria due to caudal displacement of the urethra and bladder neck causing intermittent urethral obstruction in aged dogs, suggesting an acquired etiology (1,2).

Clinical signs caused by pelvic bladder vary and male dogs may be more likely to present with urethral obstruction rather than urinary incontinence (1). It is plausible that the longer length and narrower diameter of the male urethra, predisposes it to kinking and thus obstruction; however, urethral kinking has also been identified in a female (1). Concurrently, these characteristics likely reduce the risk of urinary incontinence in cases with intrapelvic bladder. In agreement with the present findings, a recent report demonstrated dysuria in male dogs with a pelvic bladder and offer support for this assertion (2). In contrast, female dogs more commonly present with urinary incontinence due to caudal displacement of the bladder, abnormal tapering of the urethra at the junction of the bladder, and a shortened urethra (10). In addition, urethral kinking and dynamic obstruction may also occur in female dogs with severe caudal displacement of the bladder has also been documented (1,2).

Dogs in the current study ranged from 2 to 12 y of age and in 1 case had chronic upper airway disease. The youngest dog, a 2-year-old Yorkshire terrier, had a 1.5-year history of intermittent urethral obstruction, but no known predisposing clinical conditions. In this case, a congenital cause is most plausible. The third dog in this current study did not have urethral obstruction, but rather urinary incontinence as the major clinical abnormality. Urinary incontinence is more typical of pelvic bladder in female dogs although clinically normal dogs have been documented to have pelvic bladder in some cases (9,10). Urinary incontinence can result from primary mechanism sphincter incompetence as well as from caudal displacement of the urinary bladder (4). Given the history of ovariohysterectomy prior to development of incontinence, as well as incomplete resolution of incontinence following laparoscopic cystopexy, it is possible that some degree of sphincter mechanism incompetence was also present in this dog, as this is a common side effect of ovariohysterectomy (11).

Interestingly, 1 dog in the present study was a Yorkshire terrier with intermittent urethral obstruction. Yorkshire terriers represent 3 of the 4 previously reported dogs with urethral obstruction secondary to pelvic bladder (1,2). Although it is beyond the scope of the current report to suggest a predisposition in this breed, perhaps Yorkshire terriers are at increased risk for urethral obstruction associated with pelvic bladder.

Surgical time in our study was close to 70 min for all 3 dogs and the authors consider this to be reasonable. In a recent experimental study evaluating laparoscopic cystopexy in a cadaver model, the laparoscopic cystopexy was comparable to cystopexy via laparotomy, although procedure time was greater for laparoscopic cystopexy (14 versus 5 min, respectively) (6). However, the time to place cannulas, make surgical approaches and to close incisions was not included. The difference in procedure time was attributed mostly to intracorporeal suturing. Although laparoscopic suturing is technically more demanding than traditional suturing via an open abdomen, a difference of 9 min is also considered reasonable and likely insignificant compared to the time required to create and then close a traditional abdominal incision. There are numerous benefits to laparoscopic and laparoscopic-assisted techniques. Most notably is that laparoscopic techniques significantly reduce post-operative patient morbidity through decreased infection rates, reduced pain, and reduced post-operative ileus (12–15). In addition, performing procedures laparoscopically causes less tissue trauma than open approaches (12). This decrease in morbidity, therefore, likely outweighs any potential increase in anesthesia time required for intracorporeal suturing. Intracorporeal laparoscopic suturing is technically challenging and is associated with a substantial learning curve (16–18). In our cases, both intracorporeal-and extraperitoneal-suturing techniques were used. Although both methods reduce the degree of tissue trauma compared to a laparotomy approach, we recommend the intracorporeal method when the surgeon has expertise with intracorporeal suturing. The intracorporeal technique is the most minimally invasive and likely associated with less postoperative discomfort. Despite no direct comparisons of an intracorporeal- versus extraperitoneal-technique, similar recommendations have been made for laparoscopic gastropexy (18–20). Currently, an intracorporeal technique for laparoscopic gastropexy is preferred in veterinary surgery due to the reduction in postoperative pain and more rapid return to normal activity (19).

To our knowledge, this is the first clinical report of a laparoscopic or laparoscopic-assisted cystopexy for the treatment of pelvic bladder in dogs. Resolution of urethral obstruction in 2 male dogs was documented. A laparoscopic approach for cystopexy in dogs with a pelvic bladder appeared to be effective, although further studies with larger numbers of dogs are needed to confirm its effectiveness.