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Abstract

OBJECTIVE To evaluate the effect of intra-abdominal pressure (IAP) on morphology and compliance of the lower esophageal sphincter (LES) by use of impedance planimetry in healthy dogs and to quantify the effect of changes in IAP.

ANIMALS 7 healthy, purpose-bred sexually intact male hound-cross dogs.

PROCEDURES Dogs were anesthetized, and cross-sectional area (CSA), minimal diameter (MD), LES length, LES volume, and distensibility index (DI) of the LES were evaluated by use of an endoscopic functional luminal imaging probe. For each dog, measurements were obtained before (baseline) and after creation of a pneumoperitoneum at an IAP of 4, 8, and 15 mm Hg. Order of the IAPs was determined by use of a randomization software program.

RESULTS CSA and MD at 4 and 8 mm Hg were not significantly different from baseline measurements; however, CSA and MD at 15 mm Hg were both significantly greater than baseline measurements. The LES length and LES volume did not differ significantly from baseline measurements at any IAP. The DI differed inconsistently from the baseline measurement but was not substantially affected by IAP.

CONCLUSIONS AND CLINICAL RELEVANCE Pneumoperitoneum created with an IAP of 4 or 8 mm Hg did not significantly alter LES morphology in healthy dogs. Pneumoperitoneum at an IAP of 15 mm Hg caused a significant increase in CSA and MD of the LES. Compliance of the LES as measured by the DI was not greatly altered by pneumoperitoneum at an IAP of up to 15 mm Hg.

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in American Journal of Veterinary Research

Abstract

OBJECTIVE

To describe postobstructive diuresis (POD) in cats undergoing surgical placement of ureteral stents or subcutaneous ureteral bypass systems for treatment of ureteral obstruction in cats and to identify factors associated with duration and maximum severity of POD.

DESIGN

Retrospective case series.

ANIMALS

37 client-owned cats with ureteral obstruction treated between August 2010 and December 2014.

PROCEDURES

Medical records were reviewed, and data extracted included signalment, history, results from physical examinations and clinical laboratory analyses, treatment, urine output, and outcome. Data were evaluated to identify factors associated with POD duration and maximum severity, alone or in combination.

RESULTS

Serum concentrations of creatinine, potassium, phosphorus, and BUN before surgery positively correlated with duration and maximum severity of POD. Absolute changes in serum concentrations of creatinine, potassium, and BUN from before surgery to after surgery positively correlated with POD duration. Cats with anuria before surgery had longer POD than did other cats; however, there was no difference in POD duration or maximum severity with unilateral versus bilateral ureteral obstruction. Thirty-four of 37 (92%) cats survived to hospital discharge, which was not associated with whether ureteral obstruction was unilateral or bilateral. Azotemia resolved in 17 of the 34 (50%) cats that survived to hospital discharge.

CONCLUSIONS AND CLINICAL RELEVANCE

Results of the present study indicated that several factors were associated with POD duration and maximum severity, alone or in combination, and that with intensive management of fluid and electrolyte derangements, regardless of the extent of the original azotemia, a high percentage of cats survived to hospital discharge.

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in Journal of the American Veterinary Medical Association

Abstract

OBJECTIVE

To evaluate the use of transrectal ultrasonography (TRUS) for the assessment of prostatic tumors in dogs and to compare results for TRUS with results for other imaging modalities.

ANIMALS

10 client-owned male dogs.

PROCEDURES

Client-owned dogs identified with prostatic carcinoma were enrolled. Fluoroscopy, transabdominal ultrasonography (TAUS), TRUS, and MRI were performed on all dogs. Tumor measurements, urethral penetration (identification of abnormal tissue within the urethral lumen), and tumor extension into the urinary tract were recorded for all imaging modalities. Agreement between results for MRI (considered the criterion-referenced standard) and results for other modalities were compared.

RESULTS

Median body weight of the 10 dogs was 26.3 kg (range, 9.4 to 49.5 kg). No complications were encountered during or after TRUS. Significant moderate to good agreements (intraclass correlation coefficients, 0.60 to 0.86) among TAUS, TRUS, fluoroscopy, and MRI were identified for tumor length and height. Assessments of urethral penetration and tumor extension into the bladder with TRUS did not differ significantly from those made with MRI and were superior in terms of absolute agreement with MRI when compared with those for TAUS.

CONCLUSIONS AND CLINICAL RELEVANCE

TRUS was successfully and safely used to evaluate prostatic carcinoma in dogs. There was moderate to good agreement with MRI results for tumor height and length measurements, and TRUS was found to be superior to TAUS for some assessments. Transrectal ultrasonography can be considered an adjunctive imaging modality for the performance of prostatic interventional procedures or assessment of response to treatment.

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in American Journal of Veterinary Research

Abstract

Objective—To assess risk factors for recurrence of clinical signs associated with thoracolumbar intervertebral disk disease (IVDD) in dogs that had decompressive laminectomy without attempted prophylactic treatment of other disk spaces.

Design—Retrospective study.

Animals—229 dogs.

Procedure—Medical records of dogs that had decompressive laminectomy without prophylactic fenestration for a first episode of IVDD and were available for follow-up were reviewed. Information on 7 clinical and 8 radiographic potential risk factors were recorded.

Results—Clinical signs associated with recurrence of IVDD developed in 44 (19.2%) dogs. Ninety-six percent of recurrences developed within 3 years after surgery. Recurrence developed in 25% of Dachshunds and 15% of dogs of other breeds combined. Number of opacified disks was a significant risk factor for recurrence. Risk increased with number of opacified disks in an almost linear manner; each opacified disk increased risk by 1.4 times. Dogs with 5 or 6 opacified disks at the time of first surgery had a recurrence rate of 50%.

Conclusions and Clinical Relevance—When all likely episodes of recurrence are considered and a long follow-up period is achieved, true rate of recurrence of IVDD appears to be higher than in many previous reports. Dogs with multiple opacified disks at the time of first surgery should be considered a high-risk subpopulation. (J Am Vet Med Assoc 2004;225: 1231–1236)

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in Journal of the American Veterinary Medical Association

Abstract

Objective—To describe clinicopathologic features of dogs that underwent lung lobectomy for resection of primary lung tumors via video-assisted thoracoscopic surgery (VATS) or open thoracotomy (OT) and to compare short-term outcomes for dogs following these procedures.

Design—Retrospective cohort study.

Animals—46 medium- to large-breed dogs with primary lung tumors.

Procedures—Medical records of dogs that underwent a lung lobectomy via VATS (n = 22) or OT (24) for resection of primary lung tumors between 2004 and 2012 were reviewed. Dogs were included if they weighed > 10 kg (22 lb) and resection of a primary lung tumor was confirmed histologically. Tumor volumes were calculated from preoperative CT scans where available. Surgical time, completeness of excision, time in the ICU, indwelling thoracic drain time, postoperative and total hospitalization time, incidence of major complications, and short-term survival rate were evaluated.

Results—VATS was performed with a 3-port (n = 12) or 4-port (10) technique and 1-lung ventilation (22). In 2 of 22 (9%) dogs, VATS was converted to OT. All dogs survived to discharge from the hospital. There were no significant differences between the VATS and OT groups with regard to most variables. Surgery time was significantly longer for VATS than for OT (median, 120 vs 95 minutes, respectively).

Conclusions and Clinical Relevance—In medium- to large-breed dogs, short-term outcomes for dogs that underwent VATS for lung lobectomy were comparable to those of dogs that underwent OT. Further studies are required to evaluate the effects of surgical approach on indices of postoperative pain and long-term outcomes.

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in Journal of the American Veterinary Medical Association

Abstract

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.

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in Journal of the American Veterinary Medical Association

Abstract

OBJECTIVE To determine the most common types of injuries in cats surgically treated for thoracic trauma, complications associated with surgical treatment, and factors associated with mortality rate and evaluate the effectiveness of the animal trauma triage (ATT) scoring system for predicting outcome.

DESIGN Retrospective case series with nested observational study.

ANIMALS 23 client-owned cats surgically treated for thoracic trauma at 7 veterinary teaching hospitals between 1990 and 2014.

PROCEDURES Medical records were reviewed to collect data on signalment, medical history, clinical signs and physical examination findings at initial evaluation, clinicopathologic findings, initial emergency treatments and diagnostic tests performed, type of trauma sustained, imaging findings, surgery details, postoperative complications, duration of hospitalization, and cause of death, if applicable. All variables were evaluated for associations with survival to hospital discharge.

RESULTS Types of trauma that cats had sustained included dog bite or attack (n = 8 [35%]), motor vehicle accident (6 [26%]), other animal attack (2 [9%]), impalement injury or fall (2 [9%]), projectile penetrating trauma (1 [4%]), or unknown origin (4 [17%]). Intrathoracic surgery was required for 65% (15/23) of cats. The overall perioperative mortality rate was 13% (3/23). Mean ± SD ATT scores for surviving and nonsurviving cats were 6.4 ± 2.2 and 10.0 ± 1.7, respectively. Nineteen of 20 cats with no cardiopulmonary arrest survived to discharge, compared with 1 of 3 cats with cardiopulmonary arrest. Only these 2 variables were significantly associated with outcome.

CONCLUSIONS AND CLINICAL RELEVANCE The perioperative mortality rate was low in this series of cats with thoracic trauma; however, those with cardiopulmonary arrest were less likely to survive to hospital discharge than other cats. Cats with a low ATT score were more likely to survive than cats with a high ATT score.

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in Journal of the American Veterinary Medical Association

Abstract

OBJECTIVE To determine perioperative mortality rate and identify risk factors associated with outcome in dogs with thoracic trauma that underwent surgical procedures and to evaluate the utility of the animal trauma triage (ATT) score in predicting outcome.

DESIGN Retrospective case series.

ANIMALS 157 client-owned dogs.

PROCEDURES Medical records databases of 7 veterinary teaching hospitals were reviewed. Dogs were included if trauma to the thorax was documented and the patient underwent a surgical procedure. History, signalment, results of physical examination and preoperative laboratory tests, surgical procedure, perioperative complications, duration of hospital stay, and details of follow-up were recorded. Descriptive statistics and ATT scores were calculated, and logistic regression analysis was performed.

RESULTS 123 of 157 (78%) patients underwent thoracic surgery, and 134 of 157 (85.4%) survived to discharge. Mean ± SD ATT score for nonsurvivors was 8 ± 2.4. In the multivariable model, female dogs and dogs that did not experience cardiac arrest as a postoperative complication had odds of survival 6 times and 102 times, respectively, those of male dogs and dogs that did experience cardiac arrest as a postoperative complication. Additionally, patients with a mean ATT score < 7 had odds of survival 5 times those of patients with an ATT score ≥ 7.

CONCLUSIONS AND CLINICAL RELEVANCE The overall perioperative mortality rate was low for patients with thoracic trauma undergoing surgery in this study. However, male dogs and dogs that experienced cardiac arrest had a lower likelihood of survival to discharge. The ATT score may be a useful adjunct to assist clinical decision-making in veterinary patients with thoracic trauma.

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in Journal of the American Veterinary Medical Association

Abstract

Objective—To characterize in vitro coagulation status in a cohort of dogs with extrahepatic biliary tract obstruction (EHBO) and to evaluate these patients for hypercoagulability by means of thromboelastography.

Design—Prospective cohort study.

Animals—10 dogs with EHBO and 19 healthy control dogs.

Procedures—Partial or complete EHBO was confirmed via exploratory celiotomy. Venous blood samples were collected for evaluation of prothrombin time (PT) and activated partial thromboplastin time (APTT); fibrinogen and D-dimer concentrations; protein C and antithrombin activities; and factor VII, VIII, and XI coagulant activities in plasma as well as thromboelastography in whole blood. Thromboelastography variables were measured from the thromboelastography tracing, and a coagulation index was calculated. Thromboelastography results were compared with those of healthy control dogs previously evaluated by the same laboratory.

Results—Hypercoagulability was diagnosed in all dogs with EHBO on the basis of a high coagulation index. Thromboelastography variables, including maximal amplitude, α-angle, and coagulation index, were significantly higher, and K (clot formation time) and R (reaction time) were significantly lower in these dogs than in control dogs. All dogs with EHBO had PT and APTT within respective reference ranges. Plasma D-dimer and fibrinogen concentrations were above reference ranges in 8 and 7 dogs, respectively, and protein C and antithrombin activities were below reference ranges in 3 and 1 dogs, respectively.

Conclusions and Clinical Relevance—In vitro hypercoagulability was commonly detected in dogs with naturally occurring EHBO. The traditional view of EHBO as a disease that causes hypocoagulability may need to be reconsidered.

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in Journal of the American Veterinary Medical Association

Abstract

OBJECTIVE

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.

ANIMALS

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.

PROCEDURES

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.

RESULTS

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.

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in Journal of the American Veterinary Medical Association