OBJECTIVE To develop a device intended for gradual venous occlusion over 4 to 6 weeks.
SAMPLE Silicone tubing filled with various inorganic salt and polyacrylic acid (PAA) formulations and mounted within a polypropylene or polyether ether ketone (PEEK) outer ring.
PROCEDURES 15 polypropylene prototype rings were initially filled with 1 of 5 formulations and placed in PBSS. In a second test, 10 polypropylene and 7 PEEK prototype rings were filled with 1 formulation and placed in PBSS. In a third test, 2 formulations were loaded into 6 PEEK rings each, placed in physiologic solution, and incubated. In all tests, ring luminal diameter, outer diameter, and luminal area were measured over 6 weeks.
RESULTS In the first test, 2 formulations had the greatest changes in luminal area and diameter, and 1 of those had a greater linear swell rate than the other had. In the second test, 6 of 7 PEEK rings and 6 of 10 polypropylene rings closed to a luminal diamater < 1 mm within 6 weeks. Polypropylene rings had a greater increase in outer diameter than did PEEK rings between 4.5 and 6 weeks. In the third test, 11 of 12 PEEK rings gradually closed to a luminal diameter < 1 mm within 6 weeks.
CONCLUSIONS AND CLINICAL RELEVANCE A PAA and inorganic salt formulation in a prototype silicone and polymer ring resulted in gradual occlusion over 4 to 6 weeks in vitro. Prototype PEEK rings provided more reliable closure than did polypropylene rings.
OBJECTIVE To describe surgical techniques and perioperative management of dogs with von Willebrand disease (VWD) or factor VII (FVII) deficiency undergoing laparoscopic ovariohysterectomy or ovariectomy and evaluate outcomes.
DESIGN Retrospective case series.
ANIMALS 20 client-owned dogs with VWD (n = 16) or FVII deficiency (4).
PROCEDURES Dogs with VWD or FVII deficiency that underwent laparoscopic ovariohysterectomy or ovariectomy between 2012 and 2014 were retrospectively identified via a multi-institutional review of medical records.
RESULTS Median expression of von Willebrand factor was 19% (interquartile range, 18% to 30%). All 16 dogs with VWD were Doberman Pinschers, and all were pretreated with desmopressin; 4 also received cryoprecipitate. One of 4 dogs with FVII deficiency received plasma preoperatively, and 1 was treated with desmopressin; 2 dogs received no preoperative treatment. Laparoscopic ovariectomy was performed in 9 dogs with VWD and 2 dogs with FVII deficiency, laparoscopic ovariectomy with gastropexy was performed in 6 dogs with VWD and 1 dog with FVII deficiency, and laparoscopic-assisted ovariohysterectomy was performed in 1 dog with VWD and 1 dog with FVII deficiency. Iatrogenic splenic laceration requiring conversion to laparotomy occurred during trocar insertion in 1 dog with VWD. No postoperative complications, including signs of hemorrhage, were reported for any dogs.
CONCLUSIONS AND CLINICAL RELEVANCE Laparoscopic ovariohysterectomy or ovariectomy in dogs with VWD or FVII deficiency pretreated with desmopressin, cryoprecipitate, or plasma transfusions were not associated with clinical signs of hemorrhage, suggesting that minimally invasive ovariohysterectomy or ovariectomy may be considered in female dogs affected with these coagulopathies.
OBJECTIVE To evaluate a percutaneous, continuous gastric decompression technique for dogs involving a temporary T-fastener gastropexy and self-retaining decompression catheter.
ANIMALS 6 healthy male large-breed dogs.
PROCEDURES Dogs were anesthetized and positioned in dorsal recumbency with slight left-lateral obliquity. The gastric lumen was insufflated endoscopically until tympany was evident. Three T-fasteners were placed percutaneously into the gastric lumen via the right lateral aspect of the abdomen, caudal to the 13th rib and lateral to the rectus abdominis muscle. Through the center of the T-fasteners, a 5F locking pigtail catheter was inserted into the gastric lumen and attached to a device measuring gas outflow and intragastric pressure. The stomach was insufflated to 23 mm Hg, air was allowed to passively drain from the catheter until intraluminal pressure reached 5 mm Hg for 3 cycles, and the catheter was removed. Dogs were hospitalized and monitored for 72 hours.
RESULTS Mean ± SD catheter placement time was 3.3 ± 0.5 minutes. Mean intervals from catheter placement to a ≥ 50% decrease in intragastric pressure and to ≤ 6 mm Hg were 2.1 ± 1.3 minutes and 8.4 ± 5.1 minutes, respectively. After catheter removal, no gas or fluid leakage at the catheter site was visible laparoscopically or endoscopically. All dogs were clinically normal 72 hours after surgery.
CONCLUSIONS AND CLINICAL RELEVANCE The described technique was performed rapidly and provided continuous gastric decompression with no evidence of postoperative leakage in healthy dogs. Investigation is warranted to evaluate its effectiveness in dogs with gastric dilatation-volvulus.
To describe the feasibility and technique for performing laparoscopic ultrasound (LUS) of the liver in dogs.
12 client-owned dogs presenting for elective laparoscopic surgery from January 1, 2022, to October 31, 2022.
Laparoscopic exploration and LUS of the liver were performed in all dogs. Dogs were positioned in reverse Trendelenburg and laterally rotated to facilitate access to all liver lobes. Time to perform laparoscopic exploration and LUS, ability to visualize and access each liver lobe entirely, and any complications were recorded. Each dog underwent an elective laparoscopic procedure. The surgeon completed a National Aeronautics and Space Administration Task Load Index (NASA-TLX) questionnaire after surgery.
Mean body weight was 25.9 kg (SD, ± 4.1 kg; range, 5.7 to 62 kg). All liver lobes were scanned to the level of the hilus in 10/12 dogs. In 2 dogs, the caudate lobe could not be completely imaged. Median time to perform LUS was 9 minutes (IQR, 5 to 16.5 minutes), and median NASA-TLX score was 9/100 (IQR, 6.3 to 20). There was a significantly strong negative correlation between time to perform LUS (r = −0.77; P = .0037) and NASA-TLX score (r = −0.84; P = .0006) with trial number. Minor complications occurred in 2 dogs during laparoscopic exploration. No complications occurred during LUS.
LUS was feasible and safe in all dogs. The right lateral and caudate lobes were occasionally challenging to access. Technical demand and time to perform LUS improved with experience, suggesting a learning curve. Evaluation of LUS in dogs with clinical disease is warranted.
To describe surgical management and associated outcomes for dogs with primary spontaneous pneumothorax.
110 client-owned dogs with primary spontaneous pneumothorax that underwent surgical management.
Medical records at 7 veterinary teaching hospitals were reviewed. Data collected included signalment, history, clinical signs, radiographic and CT findings, surgical methods, intraoperative and postoperative complications, outcomes, and histopathologic findings. Follow-up information was obtained by contacting the referring veterinarian or owner.
110 dogs were included, with a median follow-up time of 508 days (range, 3 to 2,377 days). Ninety-nine (90%) dogs underwent median sternotomy, 9 (8%) underwent intercostal thoracotomy, and 2 (2%) underwent thoracoscopy as the sole intervention. Bullous lesions were most commonly found in the left cranial lung lobe (51/156 [33%] lesions) and right cranial lung lobe (37/156 [24%] lesions). Of the 100 dogs followed up for > 30 days, 13 (13%) had a recurrence of pneumothorax, with median time between surgery and recurrence of 9 days. Recurrence was significantly more likely to occur ≤ 30 days after surgery, compared with > 30 days after surgery. Recurrence > 30 days after surgery was rare (3 [3%]). No risk factors for recurrence were identified.
CONCLUSIONS AND CLINICAL RELEVANCE
Lung lobectomy via median sternotomy resulted in resolution of pneumothorax in most dogs with primary spontaneous pneumothorax. Recurrence of pneumothorax was most common in the immediate postoperative period, which may have reflected failure to identify lesions during the initial thoracic exploration, rather than development of additional bullae.
OBJECTIVE To evaluate the closure rate and completeness of closure for a silicone–polyacrylic acid gradual venous occlusion device placed around an intra-abdominal vein to simulate gradual occlusion of an extrahepatic portosystemic shunt.
ANIMALS 3 purpose-bred cats and 2 purpose-bred dogs.
PROCEDURES The device was surgically placed around an external (cats) or internal (dogs) iliac vein. Computed tomographic angiography was performed at the time of surgery and 2, 4, and 6 weeks after surgery. Ultrasonographic examinations of blood flow through the vein within the device were performed at the time of surgery and at weekly intervals thereafter. Dogs were euthanized 6 weeks after surgery, and the external iliac veins were harvested for histologic examination.
RESULTS The prototype gradual venous occlusion device was successfully placed in all animals, and all animals recovered without complications following the placement procedure. The vessel was completely occluded in 2 cats by 6 weeks after surgery, as determined on the basis of results of CT and ultrasonography; there was incomplete occlusion with a luminal diameter of 1.5 mm in the other cat by 6 weeks after surgery. The vessel was completely occluded in both dogs by 6 weeks after surgery. Histologic examination of the external iliac veins obtained from the dogs revealed minimal inflammation of the vessel wall and no thrombus formation.
CONCLUSIONS AND CLINICAL RELEVANCE The prototype device induced gradual attenuation of an intra-abdominal vessel over a 6-week period. This device may provide another option for gradual occlusion of extrahepatic portosystemic shunts.
To describe surgical technique, biopsy sample quality, and short-term outcome of minimally invasive small intestinal exploration and targeted abdominal organ biopsy (MISIETB) with use of a wound retraction device (WRD) in dogs.
27 client-owned dogs that underwent MISIETB with a WRD at 1 of 4 academic veterinary hospitals between January 1, 2010, and May 1, 2017.
Medical records were retrospectively reviewed, and data collected included signalment; medical history; findings from physical, ultrasonographic, laparoscopic, cytologic, and histologic evaluations; surgical indications, procedures, duration, and complications; and short-term (14-day) outcomes. The Shapiro-Wilk test was used to evaluate the normality of continuous variables, and descriptive statistics were calculated for numeric variables.
Laparoscopic exploration was performed through a multicannulated single port (n = 18), multiple ports (5), or a single 6-mm cannula (4). Median length of the incision for WRD placement was 4 cm (interquartile [25th to 75th percentile] range, 3 to 6 cm). All biopsy samples obtained had sufficient diagnostic quality. The 2 most common histologic diagnoses were lymphoplasmacytic enteritis (n = 14) and intestinal lymphoma (5). Twenty-five of 27 (93%) dogs survived to hospital discharge, and 3 (12%) dogs had postsurgical abnormalities unrelated to surgical technique.
CONCLUSIONS AND CLINICAL RELEVANCE
Results indicated that MISIETB with WRD was an effective method for obtaining diagnostic biopsy samples of the stomach, small intestine, pancreas, liver, and mesenteric lymph nodes in dogs. Prospective comparison between MISIETB with WRD and traditional laparotomy for abdominal organ biopsy in dogs is warranted.
To determine the optimal energy profile for and to assess the feasibility and efficacy of ultrasonographic and laparoscopic guidance for microwave ablation (MWA) of clinically normal canine ovaries.
44 extirpated ovaries from 22 healthy dogs.
In the first of 2 trials, 13 dogs underwent oophorectomy by routine laparotomy. Extirpated ovaries underwent MWA at 45 W for 60 (n = 11) or 90 (12) seconds; 3 ovaries did not undergo MWA and served as histologic controls. Ovaries were histologically evaluated for cell viability. Ovaries without viable cells were categorized as completely ablated. Histologic results were used to identify the optimal MWA protocol for use in the subsequent trial. In the second trial, the ovaries of 9 dogs underwent MWA at 45 W for 90 seconds in situ. Ultrasonographic guidance for MWA was deemed unfeasible after evaluation of 1 ovary. The remaining 17 ovaries underwent MWA with laparoscopic guidance, after which routine laparoscopic oophorectomy was performed. Completeness of ablation was histologically assessed for all ovaries.
2 ovaries were excluded from the trial 1 analysis because of equivocal cell viability. Six of 11 ovaries and 10 of 10 ovaries that underwent MWA for 60 and 90 seconds, respectively, were completely ablated. In trial 2, laparoscopic-guided MWA resulted in complete ablation for 12 of 17 ovaries. Dissection of the ovarian bursa for MWA probe placement facilitated complete ablation.
CONCLUSIONS AND CLINICAL RELEVANCE
Laparoscopic-guided MWA at 45 W for 90 seconds was feasible, safe, and effective for complete ablation of clinically normal ovaries in dogs.
OBJECTIVE To characterize clinical findings, surgical procedures, complications, and outcomes in dogs undergoing extirpation of masses from the cranial mediastinum via video-assisted thoracic surgery (VATS) and establish preliminary guidelines for case selection when considering VATS for thymectomy in dogs.
DESIGN Retrospective case series.
ANIMALS 18 client-owned dogs that underwent extirpation of a cranial mediastinal mass by means of VATS at 5 academic referral hospitals from 2009 through 2014.
PROCEDURES Medical records were reviewed and data extracted regarding signalment, clinical signs, physical examination findings, diagnostic imaging results, surgical approach and duration, cytologic and histologic examination results, complications, outcome, and cause of death, when applicable.
RESULTS 16 dogs had a thymoma, 1 had thymic anaplastic carcinoma, and 1 had hemangiosarcoma. Seven had both megaesophagus and myasthenia gravis. Median approximate tumor volume was 113.1 cm3 (interquartile range, 33.5 to 313.3 cm3). Median duration of VATS was 117.5 minutes (interquartile range, 91.5 to 136.3 minutes). Conversion to an open thoracic surgical procedure was required for 2 dogs, 1 of which died during surgery. Median survival time following VATS for dogs with thymoma and concurrent myasthenia gravis and megaesophagus was 20 days. Dogs with thymoma without paraneoplastic syndrome survived for ≥ 60 days, and none of these dogs died of disease-related causes.
CONCLUSIONS AND CLINICAL RELEVANCE VATS appeared to be an acceptable approach for extirpation of masses from the cranial mediastinum in dogs under certain conditions. Dogs with myasthenia gravis and megaesophagus had a poor postoperative outcome.
To determine the percentage of dogs surviving to hospital discharge and identify factors associated with death prior to hospital discharge among dogs undergoing surgery because of primary splenic torsion (PST).
Retrospective case series.
102 client-owned dogs.
Medical records of dogs with a confirmed diagnosis of PST that underwent surgery between August 1992 and May 2014 were reviewed. History, signalment, results of physical examination and preoperative bloodwork, method of splenectomy, concurrent surgical procedures, perioperative complications, duration of hospital stay, splenic histopathologic findings, and details of follow-up were recorded. Best-fit multivariate logistic regression was performed to identify perioperative factors associated with survival to hospital discharge.
93 of the 102 (91.2%) dogs survived to hospital discharge. German Shepherd Dogs (24/102 [23.5%]), Great Danes (15/102 [14.7%]), and English Bulldogs (12/102 [11.8%]) accounted for 50% of cases. Risk factors significantly associated with death prior to hospital discharge included septic peritonitis at initial examination (OR, 32.4; 95% confidence interval [CI], 2.1 to 502.0), intraoperative hemorrhage (OR, 22.6; 95% CI, 1.8 to 289.8), and postoperative development of respiratory distress (OR, 35.7; 95% CI, 2.7 to 466.0). Histopathologic evidence of splenic neoplasia was not found in any case.
CONCLUSIONS AND CLINICAL RELEVANCE
Results suggested that the prognosis for dogs undergoing splenectomy because of PST was favorable. Several risk factors for death prior to discharge were identified, including preexisting septic peritonitis, intraoperative hemorrhage, and postoperative development of respiratory distress.