Local anesthesia and hydro-distension to facilitate cystic calculus removal in horses

Surgery of the Equine Urinary Tract

Urinary surgery in the horse may be challenging. More straightforward procedures, such as urinary bladder or urachal defects, do not usually require specialized equipment or imaging, although laboratory work is helpful. Congenital or acquired conditions of the ureters or kidneys may necessitate advanced diagnostic work-ups including advanced imaging /or and minimally invasive procedures. Some surgery of the lower urinary tract is done in the sedated, standing adult horse. Surgery involving the kidney typically requires general anesthesia. Laparoscopy and associated tools are frequently used. Although many of the surgical procedures discussed are quite involved, they are becoming more commonplace.

Ex vivo comparison of single-layer and double-layer laparoscopic closure of equine bladders with 2 types of barbed sutures

OBJECTIVE

To compare laparoscopic single-layer versus double-layer closure of experimental, full-thickness incisions in adult equine urinary bladders using unidirectional and bidirectional barbed suture.

STUDY DESIGN

Experimental, ex vivo, surgical study.

SAMPLE POPULATION

Thirty adult equine cadaver urinary bladders.

METHODS

Bladders were randomly divided into 5 groups (n = 6): intact controls, bladders sutured with unidirectional or bidirectional barbed suture in a single-layer closure, and bladders sutured with unidirectional or bidirectional barbed suture in a double-layer closure. A 5-cm apical incision was created in each bladder assigned to a suture group, prior to closure in a laparoscopic trainer. After suturing, bursting pressures (BPs) were determined by filling the bladders with saline to failure. Continuous variables were compared among groups using generalized linear modeling with post hoc testing between groups, and categorical variables were compared using Fisher's exact test. Significance was set at P < .05.

RESULTS

No difference in BP was detected between treatment groups, all failing at pressures lower than those of intact bladders. The 95% confidence interval for BPs exceeded a physiologically relevant threshold of 30 mm Hg after single-layer or double-layer closure. Irrespective of treatment group, surgical time decreased with experience, and the rate of reduction was greater for the single-layer than the double-layer closures.

CONCLUSION

In this ex vivo study, both closure techniques and both suture types appeared to be acceptable for laparoscopic closure of the urinary bladder in adult horses.

Ex Vivo Biomechanical Comparison of 4 Suture Materials for Laparoscopic Bladder Closure in the Horse

OBJECTIVE

To compare a knotless, barbed suture to standard suture using laparoscopic suturing methods in an ex vivo model of equine bladder repair.

STUDY DESIGN

Cadaveric study.

SAMPLE POPULATION

Equine cadaver bladders (n=42).

METHODS

A 5-cm incision was created and repaired in a laparoscopic training box with 4 different suture materials. Groups 1 and 2 used 2-0 poliglecaprone and 2-0 glycomer knotless, barbed suture, respectively, placed using laparoscopic instruments. Groups 3 and 4 used 0 and 2-0 polyglyconate knotless, barbed suture, respectively, placed using an automated laparoscopic suturing device. All groups used a double-layer inverting pattern. Time for suture placement was recorded. Bladders were inflated with water and bursting strength pressures recorded, including a control group of intact bladders. Statistical analysis using a linear model and taking into account the unequal variances was followed by a post-hoc Tukey's test. Significance was set at P<.05.

RESULTS

Bursting strength did not vary significantly between treatment groups, but was significantly decreased compared to the control group (P<.001). Time to place the sutures with the 2 automated suture device groups (groups 3 and 4) was significantly faster than those in which the suture was placed using laparoscopic needle holders and forceps (groups 1 and 2; P=.001).

CONCLUSION

Knotless, barbed suture may be a viable alternative to standard suture material for laparoscopic closure of the urinary bladder in horses. Further cyclic and in vivo testing should be performed before use in clinical cases.

Laparoscopic removal of a bladder urolith in a standing horse

CASE DESCRIPTION

An 11-year-old Arabian gelding was evaluated for hematuria, stranguria, and pollakiuria that had been observed for 1 week.

CLINICAL FINDINGS

Transrectal palpation revealed a 5-cm firm round mass in the urinary bladder. Cystoscopy and transrectal ultrasonography confirmed the diagnosis of urinary bladder urolithiasis.

TREATMENT AND OUTCOME

A multiportal transparalumbar fossa laparoscopic approach was selected for cystotomy and urolith removal. Cystotomy and urolith removal was performed with sedation and local anesthesia with the horse standing. No perioperative complications were observed. Urination returned to normal 5 days after surgery. The horse returned to its previous level of activity at 3 weeks after surgery.

CLINICAL RELEVANCE

Findings suggested that minimally invasive transparalumbar fossa laparoscopic approach can be successfully used for cystotomy and urolith extraction in standing horses; this avoids the disadvantages of conventional laparocystotomy for removal of large uroliths in male equids and the potential complications of general anesthesia and recovery. The technique provided excellent viewing and access to the bladder, permitting extraction of the urolith and secure closure of the cystotomy with minimal tension and tissue trauma to the bladder.