Long-term management of sabulous cystitis in five horses

Five horses with sabulous cystitis were managed for up to three years. They were treated by emptying the bladder through a urinary catheter and saline lavage with cytoscopic guidance to remove residual sabulous material. The cystitis was treated with antimicrobial and anti-inflammatory medications, and bethanechol chloride was also administered. Frequent catheterisation and emptying of the bladder was an alternative to regular cystoscopic examination with saline lavage but it resulted in the development of a urethral stricture in one case. Four of the horses returned to work and one was retired owing to persistent incontinence.     

Ten cases of bladder paralysis associated with sabulous urolithiasis in horses

Bladder paralysis and sabulous urolithiasis were diagnosed in 10 horses with urinary incontinence. Additional neurological deficits in the hindquarters were detected in five of them. Treatment by catheter drainage and bladder lavage was unsuccessful, and all the horses were destroyed within 14 months of presentation. Neuritis of the cauda equina was diagnosed post mortem in one horse, but the cause of the paralysis was not identified in the others, although radiography revealed abnormal lumbosacral vertebral angulation in one case.     

Use of an active intra-abdominal drain in 67 horses

OBJECTIVE: To describe the insertion technique, efficacy, and complications associated with the use of an active (closed-suction) abdominal drain in horses. STUDY DESIGN: Retrospective study. Animals-Sixty-seven horses with abdominal contamination treated by abdominal lavage and use of a closed-suction abdominal drain. METHODS: Medical records of horses (1989-1996) that had a closed-suction abdominal drain were reviewed. Follow-up information was obtained by telephone interviews with owners. RESULTS: Sixty-eight closed-suction abdominal drains were used in 67 horses that had abdominal contamination, peritonitis, or to prevent adhesion formation. The drain was placed under general anesthesia (62 horses) or in a standing position (6 horses). Abdominal lavage was performed every 4 to 12 hours and about 83% of the peritoneal lavage solution was retrieved. Minor complications associated with drain use occurred in 49% of the horses and included obstruction or slow passage of fluid through the drain in 18 horses (26%), leakage of fluid around the drain in 11 horses (16%), and subcutaneous fluid accumulation around the drain in 8 horses (12%). Incisional suppuration developed in 20 of 62 (32%) and incisional herniation in 5 of 46 (11%) horses. CONCLUSIONS: A closed-suction drain system was easily placed and was associated with only minor complications in most horses. CLINICAL RELEVANCE: Active abdominal drainage and lavage is a useful adjunct in the treatment of peritonitis or as a prophylactic procedure in horses at risk of developing septic peritonitis and abdominal adhesions. Clinicians should be aware of the high incidence of minor complications.     

Pararectal Cystotomy for Urolith Removal in Nine Horses

Objective: To report outcome of horses after standing pararectal cystotomy for removal of uroliths. Study Design: Case series. Animals: Horses (n=9) with cystic calculi. Methods: Medical records (December 1998–May 2007) of horses with cystic calculi that had standing pararectal cystotomy were reviewed. Signalment; urolith number, size, and type; surgical technique; sedation and analgesia protocols; intra‐ and postoperative complications and outcome were analyzed. Results: Uroliths (mean diameter, 6.37 cm; median, 6 cm; range, 3–10 cm) were removed intact without need for fragmentation. Eight (89%) horses had no complications and 1 horse (11%) developed persistent drainage from the perineal incision and incisional healing was prolonged. The complications resolved after wound revision, and although cystoscopy showed absence of uroliths, the clinical signs associated with cystitis recurred. Conclusions: Cystic calculi can be removed safely in standing horses using a pararectal approach. The procedure was well tolerated and no serious complications were encountered. Clinical Relevance: Pararectal cystotomy allows removal of cystic calculi in standing sedated horses. The technique may offer an economic advantage over approaches that require general anesthesia.     

Multiple congenital urogenital abnormalities in a Tennessee Walking Horse colt

A 9-month-old, Tennessee Walking Horse colt was examined for urinary incontinence. Cystoscopy revealed a single identifiable ureter that appeared abnormal, and sabulous urolithiasis. Only the left kidney, which appeared lobulated and hydronephrotic, could be located using ultrasound. Results of serum chemistries were consistent with renal failure. Necropsy revealed unilateral agenesis of the right kidney and ureter with severe left ureterolithiasis, bilateral cryptorchidism and segmental aplasia of the ductus deferens. Histopathological examination revealed cystitis and diffuse interstitial fibrosis of the left kidney. Congenital malformations should be included as differential diagnoses for urinary incontinence and urogenital disease. Ultrasonography and cystoscopy can be useful to diagnose suspected agenesis of the urinary system in adult horses.     

Immunohistochemical expression of p63, Ki67 and β‐catenin in canine transitional cell carcinoma and polypoid cystitis of the urinary bladder

Transitional cell carcinoma (TCC) is a urinary bladder tumour associated with high mortality in dogs. In this study, we investigated the feasibility of using p63, Ki67 or β‐catenin as a clinical marker for predicting biological behaviour and prognosis in canine TCC. Expression levels of these proteins in TCC (n = 25), polypoid cystitis (n = 5) and normal urinary bladder (n = 5) were scored after immunohistochemical staining. The staining scores for p63 (P < 0.01) and β‐catenin (P < 0.05) in TCC were significantly lower than those in normal urinary bladder and polypoid cystitis. In contrast, Ki67 (P < 0.01) staining scores in TCC were significantly higher than those in normal urinary bladder and polypoid cystitis. In TCC, low p63 expression was significantly related to the presence of vessel invasion (P < 0.05) and metastasis (P < 0.01) as well as short survival time (P < 0.05). These findings show that p63 could be a reliable marker for predicting prognosis in canine TCC.     

Evaluation of a new full‐body animal rescue and transportation sling in horses: 181 horses (1998–2006)

Objective– The goal of this study was to evaluate the reliability of the Animal Rescue and Transportation Sling (ARTS) for emergency and clinical use in horses. Design– A retrospective study of the use of the ARTS in the hospital and field. Setting– The medical records of 158 horses referred to the Equine Hospital, University of Zurich, and 23 records from the Large Animal Rescue. Animals– The ARTS was used in 121 standing and 60 recumbent horses. Seventy‐eight horses were sedated, 47 patients were under general anesthesia when the sling was applied and no sedation or anesthesia was required in 56 horses. Interventions and Main Results– The ARTS was applied in crane and helicopter rescue operations to stabilize horses that required lifting (n=41), during emergency transportation (n=24), to facilitate induction of general anesthesia (n=4) or recovery from general anesthesia (n=51). Additionally, the sling was used to immobilize horses with fractures (n=29), to reduce weight‐bearing in horses with severe lameness (n=12), to support horses with disorders of the CNS (n=7), to help recumbent horses rise (n=9), and to provide support for horses after repair of large abdominal hernias (n=4). Acceptance of the ARTS by the horses was scored as excellent (n=153), good (n=19) and poor (n=6), and the sling was not tolerated in 3 horses. Only after long‐term use (weeks) did the skin over certain pressure points become irritated, resulting in superficial pressure sores. Conclusions– The ARTS was reliable, safe, and easy to use. It proved to be ideal for a wide variety of emergencies.     

Urinary incontinence and incoordination in three horses associated with equine protozoal myeloencephalitis

Urinary incontinence, weakness and ataxia associated with equine protozoal myeloencephalitis (EPM) was diagnosed in three horses. Rectal examination of all horses revealed distention of the urinary bladder. Urine was expressed when manual pressure was applied to the bladder of each horse during rectal examination. The anal reflex and tone of the anus and tail were normal in all horses. Two horses had bacterial cystitis associated with Enterococcus sp. All horses were treated with pyrimethamine and a sulfonamide for EPM, but there was a variable response to treatment.     

Urolithiasis in 68 Horses

Medical records of 68 horses with urolithiasis were examined. Calculi were in the bladder in 47 horses, urethra in 11 horses, kidneys in 15 horses, and ureter in two horses. They occurred at several sites in six horses. Common clinical signs included hematuria, altered micturition (pollakiuria, dysuria, urinary incontinence), and tenesmus. Weight loss, possibly attributable to chronic renal failure and colic, was associated more commonly with renal and ureteral calculi. Weight loss also occurred in 13% of horses with cystic calculi only. In male horses, most cystic calculi were removed by perineal (ischial) urethrotomy under epidural anesthesia. Although there were few surgical complications with urethrotomy, seven of 15 horses with follow-up suffered recurrent urolithiasis.     

Urolithiasis in the horse — A review of 13 cases

The presenting signs, treatment and postoperative progress of 13 horses with vesical and urethral calculi are reviewed. Single, discrete stones were present in 10 animals in which the results of treatment were generally good. In three horses with sabulous cystic deposits, urolithiasis was associated with bladder paralysis and the response to treatment was poor.     

Standing urogenital surgery

Caslick's, episioplasty, urethroplasty, cervical, and rectovestibular laceration repair are, by preference, performed in the standing patient. Normal castration is performed routinely uneventfully in the standing patient. The duration of the procedures and the ease with which they are accomplished in a standing horse of normal temperament make general anesthesia unnecessary. More invasive procedures, such as removal of urinary bladder calculi in male horses or removal of a neoplastic ovary in a mare, can be accomplished in a standing patient but serious consideration should be given to the use of general anesthesia. For these procedures, the potential complications are increased while the ability to effectively deal with those complications is diminished in a standing patient. For instance, imagine a mare that lays down in the stocks during a standing flank removal of an ovary or a stallion that defecates during a Gokel's approach to the bladder. Only extenuating circumstances justify these risks when general anesthesia is available.     

Efficacy of a portable oxygen concentrator with pulsed delivery for treatment of hypoxemia during equine field anesthesia

ObjectiveHypoxemia is common during equine field anesthesia. Our hypothesis was that oxygen therapy from a portable oxygen concentrator would increase PaO₂ during field anesthesia compared with the breathing of ambient air.Study designProspective clinical study.AnimalsFifteen yearling (250 – 400 kg) horses during field castration.MethodsHorses were maintained in dorsal recumbency during anesthesia with an intravenous infusion of 2000 mg ketamine and 500 mg xylazine in 1 L of 5% guaifenesin. Arterial samples for blood gas analysis were collected immediately post-induction (PI), and at 15 and 30 minutes PI. The control group (n = 6) breathed ambient air. The treatment group (n = 9) were administered pulsed-flow oxygen (192 mL per bolus) by nasal insufflation during inspiration for 15 minutes PI, then breathed ambient air. The study was performed at 1300 m above sea level. One-way and two-way repeated-measures anova with post-hoc Bonferroni tests were used for within and between-group comparisons, respectively. Significance was set at p ≤ 0.05.ResultsMean ± SD PaO₂ in controls at 0, 15 and 30 minutes PI were 46 ± 7 mmHg (6.1 ± 0.9 kPa), 42 ± 9 mmHg (5.6 ± 1.1 kPa), and 48 ± 7 mmHg (6.4 ± 0.1 kPa), respectively (p = 0.4). In treatment animals, oxygen administration significantly increased PaO₂ at 15 minutes PI to 60 ± 13 mmHg (8.0 ± 1.7 kPa), compared with baseline values of 46 ± 8 mmHg (6.1 ± 1 kPa) (p = 0.007), and 30 minute PI values of 48 ± 7 mmHg (6.5 ± 0.9 kPa) (p = 0.003).ConclusionsThese data show that a pulsed-flow delivery of oxygen can increase PaO₂ in dorsally recumbent horses during field anesthesia with ketamine-xylazine-guaifenesin.Clinical relevanceThe portable oxygen concentrator may help combat hypoxemia during field anesthesia in horses.     

Recovery of horses from general anesthesia in a darkened or illuminated recovery stall

ObjectiveTo assess whether recovery from general anesthesia, in an illuminated or a darkened stall, has an effect on time to first movement, time to standing, and recovery score.Study designProspective randomized clinical study.AnimalsTwenty-nine healthy, 2- to 5-year-old horses undergoing surgical correction of dorsal displacement of the soft palate.MethodsEach horse was assigned randomly to recover in either an illuminated (n = 15) or a darkened stall (n = 14). For pre-anesthetic medication, all horses received intravenous (IV) xylazine (0.4 mg kg⁻¹) and butorphanol (0.02 mg kg⁻¹). Anesthesia was induced with midazolam (0.1 mg kg⁻¹) and ketamine (2.2 mg kg⁻¹) IV and maintained on isoflurane in oxygen. Vital parameters, end-tidal CO₂ and isoflurane were recorded at 5-minute intervals. At the conclusion of anesthesia, horses were placed in either an illuminated or a darkened stall and xylazine (0.2 mg kg⁻¹) IV was administered at extubation. Video cameras were used to record the horses while they were allowed to recover undisturbed. Video recordings were later viewed and recoveries were evaluated on a 100-point scale by three graders.ResultsHorses in illuminated and darkened recovery stalls were evaluated on total anesthesia time, minimum alveolar concentration hours of isoflurane, time to first movement, time to standing, and total recovery score. There were no significant differences between the two groups in any of the measured parameters.ConclusionRecovering horses in a darkened versus an illuminated recovery stall may provide no benefit.Clinical relevanceDarkening the recovery stalls for horses recovering from general anesthesia may be unnecessary.     

Multivariate analysis of factors associated with post-anesthetic times to standing in isoflurane-anesthetized horses: 381 cases

Objective  To identify anesthesia-related variables which may independently predict time to standing in horses anesthetized with ketamine/diazepam/isoflurane.
Study design  Retrospective case series.
Animals  Three hundred and eighty-one horses.
Methods  Case records were searched for the years 2000–2003 and 381 horses older than 12 months which weighed at least 200 kg were identified. Data were extracted from the records, and only horses that were anesthetized with xylazine, ketamine, diazepam and isoflurane were included in the analysis. Multiple linear regression was used to relate time to standing with demographic, intraoperative and anesthetic variables.
Results  Most (326; 86%) horses recovered unassisted and 55 (14%) were assisted in recovery. The model for unassisted recovery had an R ² of 0.228 with colic ( p  < 0.0001), anesthesia duration ( p  < 0.02), temperature nadir ( p  < 0.02) and duration of hypotension ( p  < 0.0001) being significant predictors of time to standing. The final model for predicting assisted recovery time had an R ² of 0.314 with emergency status ( p  < 0.0001), warm-blood breed ( p  < 0.04) and intraoperative administration of ketamine ( p  < 0.004) being the significant predictor.
Conclusions and clinical relevance  Variables which could be impacted by the anesthetist which would result in a faster time to standing include duration of anesthesia, hypothermia and intraoperative hypotension. However, the contribution of anesthesia factors explained <23% of the variability in recovery time, suggesting that other, more important factors contribute to anesthesia recovery time in horses.     

Epidermal growth factor receptor expression in canine transitional cell carcinoma

Transitional cell carcinoma (TCC), a urinary bladder tumor with high mortality, is encountered commonly in dogs. Whereas overexpression of epidermal growth factor receptor (EGFR) is associated with development of human urinary bladder cancer, information on EGFR expression in canine TCC is lacking. In this study, EGFR protein and mRNA expression in canine normal bladder (n=5), polypoid cystitis (n=5) and TCC (n=25) were examined by immunohistochemistry and real-time polymerase chain reaction. EGFR protein expression was significantly higher in TCC than that in normal healthy bladder (P<0.001) and polypoid cystitis (P<0.005). High EGFR protein expression was significantly (P<0.01) associated with TCC with a sensitivity of 72% and specificity of 100%. Comparative analysis of protein and mRNA expression levels in TCC showed significant positive correlation (r=0.88, P<0.05) between mRNA and protein expression. These findings suggest that intense expression of EGFR protein could be used as a marker to help canine TCC diagnosis.     

Prevalence of Electrolyte Disturbances and Perianesthetic Death Risk Factors in 120 Horses Undergoing Colic Surgery

The objective of this study was to determine the prevalence of intraoperative electrolyte disturbances and risk factors associated with perianesthetic death in horses undergoing colic surgery. The files of 120 horses meeting the inclusion criteria were reviewed. Data retrieved from the medical records, including demographic data and the occurrence of electrolyte disturbances and other intraoperative complications, were analyzed with a two step-approach by univariate and multivariate logistic regression models. Hypocalcemia was the most represented electrolyte disturbance (52.5%), followed by hypokalemia (30.0%) that was associated with intraoperative administration of salbutamol (P = .045). Perianesthetic death occurred in 46 horses, accounting for an overall mortality rate of 38.3%. Risk factors associated with death were anesthetic duration (P = .001), body weight (P = .020), presence of gastric reflux before anesthesia (P = .021), and intraoperative tachycardia (P = .043) and acidosis (P = .025). The mortality in the study population was comparable to previously reported findings. Based on the study findings, it is advisable to optimize hemodynamics prior to anesthesia, in order to prevent intraoperative tachycardia that is associated with increased risk of death. Heavier horses and those with gastric reflux may have a higher risk of fatalities, and intraoperative salbutamol administration may contribute to hypokalemia.     

Endoscopic-assisted disruption of urinary calculi using a holmium:YAG laser in standing horses

OBJECTIVE: To describe a technique for endoscope-assisted disruption and removal of urinary calculi using a holmium:YAG laser in sedated, standing horses. STUDY DESIGN: Retrospective study. ANIMALS: Six horses with urinary calculi. METHODS: A holmium:YAG laser was used to disrupt naturally occurring urinary calculi in horses (4 geldings, 1 stallion, 1 mare). Ischial urethrotomy was performed in male horses to provide a portal for the endoscope and laser fiber. Calculus fragments were removed by a combination of lavage, transendoscopic basket snare removal, forceps, and digital manipulation. Ischial urethrotomies healed by second intention. Follow-up was obtained by recheck examination and telephone interview of owners. RESULTS: No major operative or postoperative complications occurred. Two calculi (1 stallion and 1 mare) were fragmented by a combination of laser ablation and manual disruption with a lithotrite. Postoperative dysuria occurred in the mare, but resolved after 1 month. Mean (+/- SD) follow-up was 306 +/- 149 days; no other complications were reported. CONCLUSIONS: Calcium carbonate urinary calculi (up to 15 cm in diameter) in horses can be effectively fragmented with a holmium:YAG laser. It is not known if this technique would be completely effective for larger calculi or extremely dense calculi. CLINICAL RELEVANCE: Calculus disruption by an endoscopically assisted holmium:YAG laser offers a minimally invasive method that can be performed in standing horses and that minimizes patient risk.     

INTRAOPERATIVE RADIOTHERAPY OF CANINE BLADDER CANCER

Thirteen dogs had partial surgical extirpation followed by whole bladder intraoperative radiotherapy for urinary bladder cancer. Eleven of the neoplasms were transitional cell carcinomas (five Stage T1, six stage T2); one was rhabdomyosarcoma (Stage T2), and one was leiomyosarcoma (Stage T2). Histopathologic evaluation showed that neoplasia extended to the margins of the excised tissue in at least 11 of the 13 dogs. Radiotherapy from a ¹³⁷Cs teletherapy machine was applied to the surgically exteriorized bladder, with doses at the 90% isodose level varying from 2188 to 2888 cGy (10 of 13 dogs receiving 2670–2700 cGy). Sixty-one percent of the dogs were alive at 1 year, 30% at 18 months, and 15% at 2 years. From the time of initial clinical signs of bladder neoplasia, 69% of the irradiated dogs were alive at 1 year, 46% at 18 months, and 23% at 2 years (one dog is still living, at 70 months). Of the owner-reported or clinically determined posttherapy complications, there was increased frequency of urination in 46% of the dogs, urinary incontinence in 46%, cystitis in 38%, and stranguria in 15%. Either persistence or recurrence of neoplasia was found in six (46%) of the dogs and metastasis in four (30%), with two of these having both recurrence and metastasis. Qualitative assessment of the complications was not done, but owner-perceived severity of the complications, metastasis, or diagnosed persistence or recurrence of the neoplasm were the major reasons for ultimately killing most of the dogs.