Search Results

Abstract

Objective—To compare outcomes of various surgical techniques for treatment of laryngeal paralysis in dogs and determine incidence and risk factors for development of postoperative complications.

Design—Retrospective study.

Animals—140 dogs undergoing surgical treatment for laryngeal paralysis at a veterinary teaching hospital between 1985 and 1998.

Procedure—Data were analyzed to determine outcome and factors influencing outcome and development of complications. Kaplan-Meier curves were constructed for survival analysis.

Results—Postoperative complications were documented in 48 (34.3%) dogs; 20 (14.3%) dogs died of related causes. Aspiration pneumonia was the most common complication (33; 23.6%). Seven dogs died of aspiration pneumonia > 1 year after surgery. Dogs that underwent bilateral arytenoid lateralization were significantly more likely to develop complications and significantly less likely to survive than were dogs that underwent unilateral arytenoid lateralization or partial laryngectomy. Factors that were significantly associated with a higher risk of dying or of developing complications included age, temporary tracheostomy placement, concurrent respiratory tract abnormalities, concurrent esophageal disease, postoperative megaesophagus, concurrent neoplastic disease, and concurrent neurologic disease.

Conclusions and Clinical Relevance—Results suggest that surgical repair of laryngeal paralysis may be associated with high postoperative complication and mortality rates. Surgical technique and concurrent problems or diseases increased the risk of complications. Dogs appeared to have a life-long risk of developing respiratory tract complications following surgical correction. (J Am Vet Med Assoc 2001;218:1949–1956)

Abstract

Objective—To determine changes in splanchnic oxygen extraction ratio during experimentally induced portal hypertension in dogs.

Animals—6 clinically normal dogs.

Procedure—Standard midline laparotomy and median sternotomy were performed in anesthetized dogs. Baseline measurements of arterial blood pressure, aortic blood flow, portal vein blood flow, and portal vein pressure were acquired, and arterial, venous, and portal vein blood samples were obtained to determine systemic and splanchnic oxygen extraction ratios. The portal vein was gradually occluded until a pressure of 18 cm of H₂O was reached; this pressure was maintained for 30 minutes, and measurements and collection of blood samples were repeated.

Results—Portal vein blood flow decreased significantly from 457 ± 136 ml/min before to 266 ± 83 ml/min after induction of portal hypertension. Oxygen content in the portal vein significantly decreased from 12.3 ± 1.85 to 8.2 ± 2.31%, and splanchnic oxygen extraction ratio significantly increased from 15.8 ± 6.2 to 37.4 ± 10.9% during portal hypertension. There was a significant inverse correlation between portal vein blood flow and splanchnic oxygen extraction ratio at baseline and during portal hypertension.

Conclusion and Clinical Relevance—An increase in splanchnic oxygen extraction ratio is evident with partial attenuation of the portal vein and the concurrent decrease in portal vein blood flow. Correlation of oxygen extraction ratio with portal vein blood flow may be a more important indicator for determination of an endpoint to prevent congestion and ischemia of the gastrointestinal tract and pancreas during ligation of portosystemic shunts. (Am J Vet Res 2002;63:15–18)

Abstract

Objective—To determine the effect of sevoflurane on cardiac energetic and hemodynamic parameters in ferrets.

Animals—7 healthy domesticated ferrets.

Procedure—Sevoflurane was used as the sole anesthetic agent for general anesthesia in ferrets. Standard midline laparotomy and median sternotomy were performed to permit instrumentation. Myocardial blood flow was determined by use of colored microsphere technology. Measurements and blood samples were obtained at 1.25%, 2.5%, and 3.75% expired concentration of sevoflurane.

Results—A dose-dependent decrease in arterial blood pressure, left ventricular pressure, systemic vascular resistance, aortic flow, and dp/dt (an index of contractility) was detected as expired concentration of sevoflurane increased. Heart rate, central venous pressure, coronary vascular resistance, myocardial oxygen extraction ratio, and (the time constant of relaxation) were unchanged. Cardiac external work decreased, as did myocardial oxygen consumption, causing increased cardiac efficiency at higher concentrations of sevoflurane.

Conclusions and Clinical Relevance—Sevoflurane caused minimal and predictable cardiovascular effects in ferrets without increasing myocardial metabolic demands. Data obtained from this study have not been previously reported for a species that is being commonly used in cardiovascular research. These findings also support use of sevoflurane as a safe inhalant anesthetic in ferrets for clinical and research settings. ( Am J Vet Res 2004:65:653–658)

Abstract

Objective—To evaluate the long-term prognosis of cats with a congenital extrahepatic portosystemic shunt (CEPSS) attenuated through gradual occlusion with cellophane banding (CB).

Design—Retrospective case series.

Animals—9 cats with a CEPSS that was attenuated with CB.

Procedures—Medical records of cats surgically treated for CEPSS by means of CB from January 2000 through March 2007 were reviewed. Extracted data included preoperative clinical signs, medications, diagnostic results including serum bile acids concentrations, surgical technique, intraoperative and postoperative complications, and long-term follow-up information.

Results—2 cats that developed refractory seizures were euthanized within 3 days after the CB procedure. Seven of the 9 cats survived to 15 days after surgery. Four cats did not have any clinical signs of CEPSS at long-term follow up. At that time, 5 cats had a postprandial SBA concentration within reference limits and 1 cat had persistent ptyalism. One cat had biurate ammonium stones removed > 2 years after surgery. One cat was euthanized 105 days after surgery because of uncontrolled seizures. The 3-year survival rate was 66%.

Conclusions and Clinical Relevance—Uncontrolled seizure activity was the most common cause of death after CB. Long-term outcome for cats with CEPSS was fair to good after the procedure. Cats with a CEPSS surviving the immediate postoperative period had a fair to good long-term outcome. Cellophane banding without intraoperative attenuation appears to be an acceptable technique for gradual occlusion of a CEPSS in cats. Cats should be monitored closely for development of neurologic disorders in the postoperative period.

Abstract

Case Description—A 12-year-old castrated male Labrador Retriever was evaluated for clinical signs associated with colorectal obstruction.

Clinical Findings—The dog had a 2-week history of tenesmus and hematochezia. On rectal examination, an annular colorectal mass was palpable extending orad into the pelvic canal. The original diagnosis of the colorectal mass was a mucosal adenoma. The dog was maintained on a low-residue diet and fecal softeners for a period of 13 months after initial diagnosis. At that time, medical management was no longer effective.

Treatment and Outcome—Placement of a colonic stent was chosen to palliate the clinical signs associated with colorectal obstruction. By use of fluoroscopic and colonoscopic guidance, a nitinol stent was placed intraluminally to open the obstructed region. Placement of the stent resulted in improvement of clinical signs, although tenesmus and obstipation occurred periodically after stent placement. At 212 days after stent placement, the patient had extensive improvement in clinical signs with minimal complications; however, clinical signs became severe at 238 days after stent placement, and the dog was euthanized. Histologic evaluation of the rectal tumor from samples obtained during necropsy revealed that the tumor had undergone malignant transformation to a carcinoma in situ.

Clinical Relevance—A stent was successfully placed in the colon and rectum to relieve obstruction associated with a tumor originally diagnosed as a benign neoplasm. Placement of colorectal stents may be an option for the palliation of colorectal obstruction secondary to neoplastic disease; however, clinical signs may persist, and continuation of medical management may be necessary.

Abstract

Objective—To determine the long-term survival rate and factors that affect survival time of domestic ferrets treated surgically for hyperadrenocorticism.

Study Design—Retrospective case series.

Animals—130 ferrets with hyperadrenocorticism that were treated surgically.

Procedures—Medical records of ferrets surgically treated for hyperadrenocorticism were reviewed. Data recorded included signalment, duration of clinical signs prior to hospital admission, CBC values, serum biochemical analysis results, anesthetic time, surgical time, concurrent diseases, adrenal gland affected (right, left, or both [bilateral]), histopathologic diagnosis, surgical procedure, caudal vena caval involvement (yes or no), postoperative melena (yes or no), days in hospital after surgery, and whether clinical signs of hyperadrenocorticism developed after surgery.

Results—130 ferrets were entered in the study (11 of 130 ferrets were admitted and underwent surgery twice). The 1- and 2-year survival rates were 98% and 88%, respectively. A 50% survival rate was never reached. Combined partial adrenal gland resection with cryosurgery had a significantly negative effect on survival time. No other risk factors were identified. Survival time was not significantly affected by either histopathologic diagnosis or specific affected adrenal gland (right, left, or bilateral).

Conclusions and Clinical Relevance—Ferrets with adrenal gland masses that were treated surgically had a good prognosis. Survival time of ferrets with hyperadrenocorticism undergoing surgery was not affected by the histologic characteristic of the tumor, the adrenal glands affected (right, left, or bilateral), or complete versus partial adrenal gland resection. Debulking was a sufficient surgical technique to allow a favorable long-term outcome when complete excision was not possible.

Abstract

Objective—To determine factors associated with long-term survival after biliary surgery in dogs.

Design—Retrospective case series.

Animals—34 dogs that underwent biliary surgery.

Procedures—Data extracted from medical records included sex, breed, body weight, age at surgery, history and clinical examination findings, preoperative and postoperative CBC, serum biochemical panel and coagulation profiles results, abdominal ultrasonographic findings, results of bacteriologic culture and histologic examination, surgical findings, postoperative complications, and survival time. Follow-up information was obtained from medical records or phone conversations with owners and referring veterinarians.

Results—Primary biliary findings included gallbladder mucocele (n = 20 dogs), inflammatory diseases (4), trauma (3), and neoplasia (1). Secondary biliary diseases included pancreatitis (n = 4), pancreatic neoplasia (1), and duodenal perforation (1). One- and 2-year survival rates were both 66%. Increasing age; γ-glutamyltransferase activity; preanesthetic heart rate; BUN, phosphorus, and bilirubin concentrations; and the use of biliary diversion procedures were risk factors for death, although pancreatitis was not. However, poor long-term survival was associated with pancreatitis.

Conclusions and Clinical Relevance—Long-term prognosis was guarded after biliary surgery in dogs. However, dogs that survived the early postoperative period had good long-term prognosis. Dogs with pancreatitis had poor prognosis. Overall, the prognosis was worse for dogs that underwent a biliary diversion, compared with dogs that did not.

Abstract

Objective—To evaluate risk factors associated with death and development of perioperative complications in dogs undergoing surgery for treatment of gastric dilatation-volvulus (GDV).

Design—Retrospective case series.

Animals—166 dogs.

Procedures—Records of dogs with confirmed GDV that underwent surgery were reviewed. Logistic regression was performed to identify factors associated with development of complications (ie, hypotension, arrhythmias, gastric necrosis necessitating gastrectomy, disseminated intravascular coagulation, peritonitis, sepsis, postoperative dilatation, postoperative vomiting, and incisional problems) and with short-term outcome (ie, died vs survived to the time of suture removal).

Results—Short-term mortality rate was 16.2% (27/166). Risk factors significantly associated with death prior to suture removal were clinical signs for > 6 hours prior to examination, combined splenectomy and partial gastrectomy, hypotension at any time during hospitalization, peritonitis, sepsis, and disseminated intravascular coagulation. Partial gastrectomy was not a significant risk factor for death but was for peritonitis, disseminated intravascular coagulation, sepsis, and arrhythmias. Age, gastrectomy, and disseminated intravascular coagulation were risk factors for development of hypotension. Use of a synthetic colloid or hypertonic saline solution was associated with a significantly decreased risk of hypotension.

Conclusions and Clinical Relevance—Results suggest that the prognosis for dogs undergoing surgery because of GDV is good but that certain factors are associated with an increased risk that dogs will develop perioperative complications or die.