Philipp D. Mayhew

The effect of laparoscopic versus open ovariectomy on postsurgical activity in small dogs.

OBJECTIVE To describe a technique for laparoscopic ovariectomy (LapOVE) in small dogs, and compare the surgical time, complications, and postoperative activity of dogs undergoing LapOVE to those undergoing conventional traditional open ovariectomy (OOVE). STUDY DESIGN A randomized, controlled clinical trial. ANIMALS Intact small breed (<10 kg) female dogs (n=20). METHODS Ventral median celiotomy was performed for OOVE. A 2-midline portal technique using a 3.5 mm laparoscope port and a 6 mm instrument portal was used for LapOVE. An accelerometer was attached to the collar of each dog to record 24-hour preoperative and 48-hour postoperative activity. Total activity counts recorded before surgery were compared with total counts recorded after surgery. The percent change in counts after surgery was compared between OOVE- and LapOVE-treated dogs. RESULTS No major complications occurred and surgical time for LapOVE was significantly longer than for OOVE cases (P=.005). Dogs in the LapOVE group had a 25% decrease in total activity counts after surgery (95% confidence interval [CI]: 11-38%), whereas dogs in the OOVE group had a 62% decrease in total activity counts after surgery (95% CI: 48-76%). CONCLUSIONS Both procedures were performed with reasonable surgical times and without major complication. Postoperative activity, as measured by accelerometry, was significantly different between the 2 groups. CLINICAL RELEVANCE Laparoscopy is a safe method for ovariectomy in small dogs and results in increased postoperative activity counts when compared with an open technique.

Pathogenesis and outcome of extrahepatic biliary obstruction in cats

Extrahepatic biliary obstruction (EHBO) was confirmed at surgery or necropsy in 22 cats. Biliary or pancreatic adenocarcinoma was diagnosed by histopathology in six cats and one cat had an undiagnosed mass in the common bile duct. The remaining 15 cats had at least one of a complex of inflammatory diseases including pancreatitis, cholangiohepatitis, cholelithiasis and cholecystitis. The most common clinical signs were jaundice, anorexia, lethargy, weight loss and vomiting. Hyperbilirubinaemia was present in all cases. Distension of the common bile duct and gall bladder was the most commonly observed finding on abdominal ultrasound. Nineteen cats underwent exploratory laparotomy for biliary decompression and diversion. Mortality in cats with underlying neoplasia was 100 per cent and, in those with non‐neoplastic lesions, was 40 per cent. Long‐term complications, in those that survived, included recurrence of cholangiohepatitis, chronic weight loss and recurrence of obstruction. Based on these findings, the prognosis for EHBO in cats must be considered guarded.

Prospective Evaluation of Two Intracorporeally Sutured Prophylactic Laparoscopic Gastropexy Techniques Compared with Laparoscopic-Assisted Gastropexy in Dogs

OBJECTIVE To report technique, surgical time, complication rate, and postoperative activity in dogs undergoing 2 intracorporeally-sutured total laparoscopic gastropexy (TLG) techniques compared with a laparoscopic-assisted gastropexy (LAG) technique. STUDY DESIGN Randomized clinical trial. ANIMALS Dogs (n=30) weighing >25 kg. METHODS Dogs were randomly assigned to 1 of 3 groups. Two TLG techniques were performed using a median 3 portal technique. One of 2 suturing techniques was used to approximate corresponding incisions made in the stomach and body wall; using intracorporeal hand-suturing or a suture-assist device (Endostitch). In a 3rd group, a previously reported LAG technique was used. All dogs had an activity monitor placed for 7 days pre- and postoperatively. Linear regression analyses were performed to evaluate the association of surgical procedure on gastropexy time and the percentage change in activity counts. RESULTS Median gastropexy time was 28 minutes (range, 20-41 minutes) for LAG, 48 minutes (range, 39-61 minutes) for the hand suture TLG technique, and 56 minutes (range, 30-90 minutes) for the Endostitch TLG technique. LAG was performed faster than TLG (P<.05). LAG dogs had a greater decrease in postoperative activity than TLG dogs (P=.005); however there was no difference in surgical time or postoperative activity between TLG techniques. CONCLUSIONS TLG can be performed safely and effectively in dogs and although it takes longer, it has less impact on postoperative activity compared with LAG. CLINICAL RELEVANCE TLG techniques may have advantages over LAG as measured by a greater willingness of dogs to move around postoperatively.

Comparison of surgical site infection rates in clean and clean-contaminated wounds in dogs and cats after minimally invasive versus open surgery: 179 cases (2007–2008)

OBJECTIVE To report and compare the surgical site infection (SSI) rates for clean and clean-contaminated procedures performed by either a minimally invasive surgical or open surgical approach in a large population of dogs and cats. DESIGN Prospective case series. ANIMALS 179 patients (dogs and cats) undergoing minimally invasive abdominal or thoracic surgery. PROCEDURES Case information from all animals that underwent minimally invasive abdominal or thoracic surgery was prospectively collected and compared with an existing database of the same information collected from 379 patients undergoing laparotomy or thoracotomy via an open surgical approach. For both groups, an SSI was defined as any surgical wound in which purulent discharge was observed within 14 days after the procedure. Follow-up for all patients was obtained by direct examination or telephone interviews. RESULTS Overall SSI rate in the minimally invasive surgery (MIS) group was 1.7% and in the open surgery (OS) group was 5.5%. On univariate analysis, there was a significantly lower SSI rate in the MIS group, compared with the SSI rate for the OS group. On multivariable logistic regression analysis, this difference appeared to be a result of the fact that surgery times were longer (median, 105 vs 75 minutes) and hair was clipped ≥ 4 hours prior to surgery for more animals (23% vs 11 %) in the OS group, compared with the MIS group. CONCLUSIONS AND CLINICAL RELEVANCE MIS may be associated with a lower SSI rate, compared with OS, but confounding factors such as differences in surgery time and preoperative preparation contributed in part to this finding. As such, surgical approach cannot be categorized as an independent risk factor for SSIs in small animals until further studies are performed.

Laparoscopic cholecystectomy for management of uncomplicated gall bladder mucocele in six dogs.

OBJECTIVES To describe a technique for, and outcome after, laparoscopic cholecystectomy (LC) for management of uncomplicated gall bladder mucocele (GBM) in dogs. STUDY DESIGN Case series. ANIMALS Dogs (n=6) with uncomplicated GBM. METHODS Dogs with ultrasonographic evidence of GBM but without imaging or laboratory signs of gall bladder rupture, peritonitis, or extra-hepatic biliary tract rupture that had LC were included. A 4 portal technique was used. A fan retractor was used to retract the gall bladder to allow dissection around the cystic duct with 5 or 10 mm right-angle dissecting forceps. The cystic duct was ligated using extracorporeally tied ligatures supplemented sometimes with hemostatic clips. A harmonic scalpel was used to dissect the gall bladder from its fossa. The gall bladder was placed into a specimen retrieval bag and after bile aspiration the bag was withdrawn through the 11 mm portal incision. RESULTS Five dogs had mild intermittent clinical signs including vomiting, inappetence, and lethargy. All dogs had successful LC without conversion to an open approach. All dogs with clinical signs had improvement or resolution of signs postoperatively. No important perioperative complications occurred and all dogs were alive at a median of 8 months postoperatively (range, 3-14 months). CONCLUSIONS LC can be accomplished safely and effectively in dogs with uncomplicated GBM. CLINICAL RELEVANCE A minimally invasive approach for cholecystectomy can be used for the treatment of GBM in dogs.

Gall bladder mucoceles and their association with endocrinopathies in dogs: a retrospective case-control study

OBJECTIVE To investigate the relationship between endocrinopathies and diagnosis of gall bladder mucocele in dogs via a retrospective case-control study. METHODS Records of 78 dogs with a surgical or ultrasonographic diagnosis of gall bladder mucocele were examined for the presence or absence of hyperadrenocorticism, hypothyroidism and diabetes mellitus. Two age- and breed-matched controls for each gall bladder mucocele dog (156 total control dogs) were examined for the same concurrent diseases. A matched case-control analysis was performed using conditional logistic regression. RESULTS The odds of mucocele in dogs with hyperadrenocorticism were 29 times that of dogs without hyperadrenocorticism (P=0.001; 95 per cent CI 3.8, 219.9). No difference was found between dogs with and without diabetes mellitus. Although a significant association was found between gall bladder mucocele and hypothyroidism, potential observation bias was also identifi ed. CLINICAL SIGNIFICANCE Hyperadrenocorticoid dogs that were presented for acute illness with laboratory evidence of hepatobiliary disease should undergo evaluation for the presence of a biliary mucocele. Dogs diagnosed with a gall bladder mucocele should be screened for concurrent hyperadrenocorticism if clinical suspicion exists.

Association of Cauda Equina Compression on Magnetic Resonance Images and Clinical Signs in Dogs With Degenerative Lumbosacral Stenosis

Magnetic resonance imaging (MRI) was used to examine the lumbosacral spine of 27 dogs with degenerative lumbosacral stenosis. Four normal dogs were also similarly imaged. Compression of the soft-tissue structures within the vertebral canal at the lumbosacral space was assessed in two ways: by measuring dorsoventral diameter on T1-weighted sagittal images and cross-sectional area on transverse images. The severity of the clinical signs was compared to the severity of cauda equina compression. No significant correlation was found. It is concluded that degree of compression as determined by MRI at time of presentation is independent of disease severity.

Use of cystoscopic-guided laser ablation for treatment of intramural ureteral ectopia in male dogs: four cases (2006–2007)

OBJECTIVE To describe and evaluate the outcome of cystoscopic-guided laser ablation of intramural ureteral ectopia in male dogs. DESIGN Retrospective case series. ANIMALS 4 incontinent male dogs with intramural ureteral ectopia. PROCEDURES Intramural ectopic ureters were diagnosed via preoperative computed tomography-IV urography and subsequent cystoscopy. Transurethral cystoscopic-guided laser ablation (diode laser [n = 3 dogs] and holmium:yttrium aluminum garnet laser [1]) was performed to proximally relocate the ectopic ureteral orifice to the urinary bladder. Fluoroscopy was used during the procedures to confirm that the ureteral tract was intramural and the ureteral orifice was intravesicular after the procedure. In 1 dog with bilateral ureteral ectopia, staged laser ablation was performed at 6-week intervals because of difficulty viewing the second ureter on the first attempt. All ureteral orifices were initially located in the middle to proximal portion of the prostatic portion of the urethra. Six weeks after surgery, imaging was repeated in 3 of 4 dogs. RESULTS Postoperative dysuria or hematuria did not develop. All dogs were immediately continent after laser treatment and remained so at a median follow-up period of 18 months (range, 15 to 20 months) without medical management. CONCLUSIONS AND CLINICAL RELEVANCE Ureteral ectopia can cause urinary incontinence in male dogs and is usually associated with other urinary tract abnormalities. Cystoscopic-guided laser ablation provided an effective and minimally invasive alternative to surgical management of intramural ureteral ectopia.

Evaluation of single port access gastropexy and ovariectomy using articulating instruments and angled telescopes in dogs

OBJECTIVE To describe in dogs, a technique for single port access gastropexy and ovariectomy (SPAGO) using a commercially available multitrocar port and to evaluate short-term outcome. DESIGN Retrospective case series. ANIMALS Dogs (n = 18). PROCEDURES A commercially available multitrocar port was inserted into the abdomen lateral to the rectus abdominis muscle and 2-5 cm caudal to the right rib. Dogs were tilted 45° in both left and right recumbency and bilateral ovariectomy performed using articulating graspers, a bipolar vessel sealing device and a 30° telescope. The laparoscopic assisted incisional gastropexy was performed after ovariectomy at the multitrocar port insertion site by grasping the antral portion of the stomach with a 10 mm DuVall forceps and suturing the seromuscular layer of the antral region of the stomach to the transversus abdominis muscle. RESULTS Eighteen dogs (median weight, 34.5 kg; range, 14.7-59.2 kg) met the inclusion criteria. Median surgical time for SPAGO was 65 minutes (range, 50-225 minutes). Intra-operative complications included, incorrect multitrocar port placement location (n = 3) and mild hemorrhage from a splenic laceration (1) All dogs recovered from surgery and were discharged from the hospital. CONCLUSIONS Single port access gastropexy and ovariectomy is a feasible procedure to provide prophylaxis against gastric dilation-volvulus and a simultaneous means of sterilization in female dogs. Careful and accurate initial multitrocar port insertion is necessary to have optimal operative viewing as well as to reduce the chances of inadvertent splenic laceration.

Thoracoscopic Subphrenic Pericardectomy Using Double-Lumen Endobronchial Intubation for Alternating One-Lung Ventilation

OBJECTIVE To report the technique, complications, and effectiveness of thoracoscopic subphrenic pericardectomy (SPP) using double-lumen endobronchial intubation for alternating 1-lung (OLV) in healthy dogs. STUDY DESIGN Prospective cohort study. ANIMALS Mature purpose-bred dogs (n=7). METHODS Bronchoscope-assisted placement of a left-sided double-lumen endobronchial tube, immediately before surgery, allowed intraoperative alternation of ventilation between lung fields. A camera portal was established in a subxyphoid location. Two instrument portals were established at the 4th-6th intercostal spaces on the right and left sides. A vessel-sealing device was used to create the subphrenic pericardectomy. After termination of the procedure, dogs were humanely euthanatized under anesthesia and necropsy performed. In each dog, the extent of pericardectomy and any complications were evaluated. RESULTS Technical difficulties with tube placement occurred in 4 dogs, but alternating OLV was achieved in all dogs and SPP completed successfully. Median surgical time was 87.5 minutes (range, 80-105 minutes). At necropsy, 0.5-2 cm of pericardial tissue remained ventral to the intact phrenic nerve in 6 dogs; in 1 dog, the phrenic nerve was transected on the left side only. CONCLUSIONS Thoracoscopic subphrenic pericardectomy is a technically feasible procedure in healthy dogs. Double-lumen endobronchial intubation allowed alternating OLV without intraoperative bronchoscopically guided tube manipulation in all but 1 dog. CLINICAL RELEVANCE Thoracoscopic subphrenic pericardectomy could potentially be used for management of conditions where relief of pericardial constriction or access to intrapericardial structures is desired.