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- Author or Editor: William A. Brown x
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Abstract
Objective—To determine whether muscle moment arms at the carpal and metacarpophalangeal joints can be modeled as fixed-radius pulleys for the range of motion associated with the stance phase of the gait in equine forelimbs.
Sample Population—4 cadaveric forelimbs from 2 healthy Thoroughbreds.
Procedure—Thin wire cables were sutured at the musculotendinous junction of 9 forelimb muscles. The cables passed through eyelets at each muscle's origin, wrapped around single-turn potentiometers, and were loaded. Tendon excursions, measured as the changes in lengths of the cables, were recorded during manual rotation of the carpal (180° to 70°) and metacarpophalangeal (220° to 110°) joints. Extension of the metacarpophalangeal joint (180° and 220°) was forced with an independent loading frame. Joint angle was monitored with a calibrated potentiometer. Moment arms were calculated from the slopes of the muscle length versus joint angle curves.
Results—At the metacarpophalangeal joint, digital flexor muscle moment arms changed in magnitude by ≤ 38% during metacarpophalangeal joint extension. Extensor muscle moment arms at the carpal and metacarpophalangeal joints also varied (≤ 41% at the carpus) over the range of joint motion associated with the stance phase of the gait.
Conclusions and Clinical Relevance—Our findings suggest that, apart from the carpal flexor muscles, muscle moment arms in equine forelimbs cannot be modeled as fixed-radius pulleys. Assuming that muscle moment arms at the carpal and metacarpophalangeal joints have constant magnitudes may lead to erroneous estimates of muscle forces in equine forelimbs. (Am J Vet Res 2003;64:351–357)
Abstract
OBJECTIVE To describe the operative technique, complications, and conversion rates for laparoscopic liver biopsy (LLB) in dogs and evaluate short-term clinical outcome for dogs that underwent the procedure.
DESIGN Retrospective case series.
ANIMALS 106 client-owned dogs.
PROCEDURES Medical records were reviewed to identify dogs that underwent an LLB with a single-port or multiport technique at either of 2 veterinary teaching hospitals from August 2003 to September 2013. Demographic and laboratory data, preoperative administration of fresh frozen plasma, procedural and diagnostic information, intraoperative complications, and survival to discharge were recorded. The LLB specimens were obtained with 5-mm laparoscopic biopsy cup forceps and a grasp-and-twist technique.
RESULTS Prior to surgery, 25 of 94 (27%) dogs had coagulopathy (prothrombin time or partial thromboplastin time greater than the facility reference ranges, regardless of platelet count). Twenty-one dogs were thrombocytopenic, 14 had ascites, and 14 received fresh frozen plasma transfusion before surgery. In all cases, biopsy samples collected were of sufficient size and quality for histopathologic evaluation. Two dogs required conversion to an open laparotomy because of splenic laceration during initial port placement. One hundred one of 106 dogs survived to discharge; 5 were euthanized during hospitalization owing to progression of liver disease and poor prognosis.
CONCLUSIONS AND CLINICAL RELEVANCE Single-port and multiport LLB were found to be effective, minimally invasive diagnostic techniques with a low rate of complications. Results suggested LLB can be safely used in dogs with underlying coagulopathies and advanced liver disease.
Abstract
OBJECTIVE
To determine complication rates for dogs in which full-thickness large intestinal incisions were performed, assess potential risk factors for death during hospitalization and for intestinal dehiscence following these surgeries, and report short-term mortality rates for these patients.
ANIMALS
90 dogs.
PROCEDURES
Medical records of 4 veterinary referral hospitals were reviewed to identify dogs that underwent large intestinal surgery requiring full-thickness incisions. Signalment, history, clinicopathologic data, medical treatments, surgical procedures, complications, and outcomes were recorded. Descriptive statistics were calculated; data were analyzed for association with survival to discharge (with logistic regression analysis) and postoperative intestinal dehiscence (with Fisher exact or Wilcoxon rank sum tests).
RESULTS
Overall 7-day postoperative intestinal dehiscence and mortality rates were 9 of 90 (10%) and 15 of 90 (17%). Dogs with preoperative anorexia, hypoglycemia, or neutrophils with toxic changes and those that received preoperative antimicrobial treatment had greater odds of death than did dogs without these findings. Preexisting colon trauma or dehiscence, preexisting peritonitis, administration of blood products, administration of > 2 classes of antimicrobials, positive microbial culture results for a surgical sample, and open abdominal management of peritonitis after surgery were associated with development of intestinal dehiscence. Five of 9 dogs with intestinal dehiscence died or were euthanized.
CONCLUSIONS AND CLINICAL RELEVANCE
Factors associated with failure to survive to discharge were considered suggestive of sepsis. Results suggested the dehiscence rate for full-thickness large intestinal incisions may not be as high as previously reported, but several factors may influence this outcome and larger, longer-term studies are needed to confirm these findings.
Abstract
OBJECTIVE
To evaluate short-term risk factors associated with dehiscence and death in cats undergoing full-thickness large intestinal incisions.
ANIMALS
84 client-owned cats that had undergone full-thickness large intestinal incisions and for which information regarding outcome through postoperative day 7 was available.
PROCEDURES
Medical records from 4 veterinary teaching hospitals were reviewed. For cats that met the inclusion criteria, signalment, history, laboratory test results, surgical and medical procedures, perioperative complications, and outcome were analyzed. A Fisher exact or Wilcoxon rank sum test was used to identify individual variables associated with dehiscence of intestinal incisions or patient nonsurvival to hospital discharge or both.
RESULTS
84 cats met the inclusion criteria. The overall dehiscence and survival to hospital discharge rates were 8.3% (7/84 cats) and 94% (79/84 cats), respectively. Factors associated with dehiscence and nonsurvival to hospital discharge included presence of band neutrophils, performance of partial colectomy with colonic resection and anastomosis, administration of blood products, postoperative cardiopulmonary arrest, and incisional inflammation or infection. Factors associated with nonsurvival to hospital discharge only included low serum globulin concentration, repair of colonic trauma or dehiscence, and postoperative colonic dehiscence. Factors associated with dehiscence only included hypoalbuminemia, renal dysfunction, administration of blood products or > 2 classes of antimicrobials, and intra-abdominal fecal contamination.
CONCLUSIONS AND CLINICAL RELEVANCE
Results indicated that intestinal dehiscence and mortality rates associated with large intestinal incisions in cats may be higher than previously proposed, although the risk of either outcome was still low. Factors suggestive of systemic illness were associated with colonic dehiscence or death, and focused prospective studies of risk factors are warranted. (J Am Vet Med Assoc 2021;259:162–171)
Abstract
OBJECTIVE
To evaluate radiation exposure of dogs and cats undergoing procedures requiring intraoperative fluoroscopy and for operators performing those procedures.
SAMPLE
360 fluoroscopic procedures performed at 2 academic institutions between 2012 and 2015.
PROCEDURES
Fluoroscopic procedures were classified as vascular, urinary, respiratory, cardiac, gastrointestinal, and orthopedic. Fluoroscopy operators were classified as interventional radiology-trained clinicians, orthopedic surgeons, soft tissue surgeons, internists, and cardiologists. Total radiation exposure in milligrays and total fluoroscopy time in minutes were obtained from dose reports for 4 C-arm units. Kruskal-Wallis equality of populations rank tests and Dunn pairwise comparisons were used to compare differences in time and exposure among procedures and operators.
RESULTS
Fluoroscopy time (median, 35.80 minutes; range, 0.60 to 84.70 minutes) was significantly greater and radiation exposure (median, 137.00 mGy; range, 3.00 to 617.51 mGy) was significantly higher for vascular procedures than for other procedures. Median total radiation exposure was significantly higher for procedures performed by interventional radiology-trained clinicians (16.10 mGy; range, 0.44 to 617.50 mGy), cardiologists (25.82 mGy; range, 0.33 to 287.45 mGy), and internists (25.24 mGy; range, 3.58 to 185.79 mGy).
CONCLUSIONS AND CLINICAL RELEVANCE
Vascular fluoroscopic procedures were associated with significantly longer fluoroscopy time and higher radiation exposure than were other evaluated fluoroscopic procedures. Future studies should focus on quantitative radiation monitoring for patients and operators, importance of operator training, intraoperative safety measures, and protocols for postoperative monitoring of patients.
Abstract
Objective—To evaluate a portable real-time reverse transcriptase-polymerase chain reaction (RT-PCR) assay designed to detect all 7 viral serotypes of footand- mouth disease virus (FMDV).
Design—Laboratory and animal studies.
Study Population—Viruses grown in tissue culture and animals experimentally infected with FMDV.
Procedure—1 steer, pig, and sheep were infected with serotype O FMDV. Twenty-four hours later, animals were placed in separate rooms that contained 4 FMDV-free, healthy animals of the same species. Oral and nasal swab specimens, oropharyngeal specimens obtained with a probang, and blood samples were obtained at frequent intervals, and animals were observed for fever and clinical signs of foot-and-mouth disease (FMD). Samples from animals and tissue cultures were assayed for infectious virus and viral RNA.
Results—The assay detected viral RNA representing all 7 FMDV serotypes grown in tissue culture but did not amplify a panel of selected viruses that included those that cause vesicular diseases similar to FMD; thus, the assay had a specificity of 100%, depending on the panel selected. The assay also met or exceeded sensitivity of viral culture on samples from experimentally infected animals. In many instances, the assay detected viral RNA in the mouth and nose 24 to 96 hours before the onset of clinical disease.
Conclusions and Clinical Relevance—The assay reagents are produced in a vitrified form, which permits storage and transportation at ambient temperatures. The test can be performed in 2 hours or less on a portable instrument, thus providing a rapid, portable, sensitive, and specific method for detection of FMDV. (J Am Vet Med Assoc 2002;220:1636–1642)
Abstract
Objective—To determine the efficacy of long-term enalapril administration in delaying the onset of congestive heart failure (CHF).
Design—Placebo-controlled, double-blind, multicenter, randomized trial.
Animals—124 dogs with compensated mitral valve regurgitation (MR).
Procedures—Dogs randomly assigned to receive enalapril or placebo were monitored for the primary endpoint of onset of CHF for ≤ 58 months. Secondary endpoints included time from study entry to the combined endpoint of CHF-all-cause death; number of dogs free of CHF at 500, 1,000, and 1,500 days; and mean number of CHF-free days.
Results—Kaplan-Meier estimates of the effect of enalapril on the primary endpoint did not reveal a significant treatment benefit. Chronic enalapril administration did have a significant benefit on the combined endpoint of CHF-all-cause death (benefit was 317 days [10.6 months]). Dogs receiving enalapril remained free of CHF for a significantly longer time than those receiving placebo and were significantly more likely to be free of CHF at day 500 and at study end.
Conclusions and Clinical Relevance—Chronic enalapril treatment of dogs with naturally occurring, moderate to severe MR significantly delayed onset of CHF, compared with placebo, on the basis of number of CHF-free days, number of dogs free of CHF at days 500 and study end, and increased time to a combined secondary endpoint of CHF-all-cause death. Improvement in the primary endpoint, CHF-free survival, was not significant. Results suggest that enalapril modestly delays the onset of CHF in dogs with moderate to severe MR.
Abstract
Objective—To determine the effect of long-term administration of enalapril on renal function in dogs with severe, compensated mitral regurgitation.
Design—Randomized controlled trial.
Animals—139 dogs with mitral regurgitation but without overt signs of heart failure.
Procedure—Dogs were randomly assigned to be treated with enalapril (0.5 mg/kg [0.23 mg/lb], PO, q 24 h) or placebo, and serum creatinine and urea nitrogen concentrations were measured at regular intervals for up to 26 months.
Results—Adequate information on renal function was obtained from 132 dogs; follow-up time ranged from 0.5 to 26 months (median, 12 months). Mean serum creatinine and urea nitrogen concentrations were not significantly different between dogs receiving enalapril and dogs receiving the placebo at any time, nor were concentrations significantly different from baseline concentrations. Proportions of dogs that developed azotemia or that had a ≥ 35% increase in serum creatinine or urea nitrogen concentration were also not significantly different between groups.
Conclusions and Clinical Relevance—Results suggest that administration of enalapril for up to 2 years did not have any demonstrable adverse effects on renal function in dogs with severe, compensated mitral regurgitation. (J Am Vet Med Assoc 2002;221: 654–658)
