Objective—To determine whether free radicals are
produced in ischemic and reperfused canine skeletal
muscle, whether free radicals can be detected from
effluent blood by use of spin-trapping electron paramagnetic
resonance (EPR) spectroscopy, and
whether free radical-induced skeletal muscle damage
is detectable by use of light microscopy.
Animals—6 healthy mixed-breed dogs.
Procedures—Dogs were anesthetized and both gracilis
muscles were isolated, leaving only the major
vascular pedicle intact. Ischemia was induced in 1
flap for 4 hours; the contralateral flap served as the
control. Ischemic flaps were then reperfused for 15
minutes. α-Phenyl-N-tert-butylnitrone, a spin-trapping
agent, was administered intravenously to each dog 1
hour prior to reperfusion. Following reperfusion, effluent
blood samples from muscle flaps were obtained
and processed for EPR spectroscopy. Muscle biopsy
specimens were obtained for histologic evaluation,
and dogs were euthanatized.
Results—Spin adducts were not detected in blood
from control flaps. However, spin adducts were
detected in all ischemic-reperfused muscle flaps.
Principal signals identified were characteristic of oxygen-
and carbon-centered radicals. Significantly more
muscle damage was detected in ischemic-reperfused
flaps, compared with control flaps.
Conclusions and Clinical Relevance—Free radicals
may be an important component of injury
induced by ischemia and reperfusion of canine
skeletal muscle. Spin-trap adducts of free radicals
can be detected in effluent blood of canine muscle
flaps by use of spin-trapping EPR spectroscopy.
Spin-trapping EPR spectroscopy may be useful for
the study of antioxidants and free radical scavengers
in attenuating ischemia and reperfusionmediated
skeletal muscle damage. (Am J Vet Res
Objective—To determine whether adenosine pretreatment
attenuates free radical production and muscle
damage in ischemic and reperfused canine skeletal
Animals—9 healthy mixed-breed dogs.
Procedure—Dogs were anesthetized, and both gracilis
muscles were isolated, leaving only the major
vascular pedicle intact. Saline (0.9% NaCl) solution
was injected into the artery supplying the control flap,
whereas adenosine (10 mg) was injected into the contralateral
artery. Ischemia was induced in both flaps
for 4 hours. α-Phenyl-N-tert-butylnitrone was administered
IV to each dog 1 hour prior to reperfusion.
Following 15 minutes of reperfusion, effluent blood
samples from each muscle flap were obtained and
processed for spin-trapping electron paramagnetic
resonance (EPR) spectroscopy. Muscle biopsy specimens
were obtained for histologic evaluation, and
dogs were euthanatized.
Results—EPR spectra of strong intensity were
obtained from analysis of 5 of 9 paired samples.
Signals identified were characteristic of oxygen- and
carbon-centered free radical adducts. Signal intensity
of spectra from adenosine-treated flaps was significantly
less than that of control flaps; mean signal
attenuation was 36% in the adenosine-treated group.
Histologic evaluation of muscle flaps did not reveal
significant differences between groups.
Conclusions and Clinical Relevance—Treatment of
canine muscle flaps with adenosine prior to a period
of ischemia reduced but did not completely attenuate
free radical production after reperfusion. However,
adenosine pretreatment did not affect histologic
abnormalities. (Am J Vet Res 2002;63:175–180)
Objective—To determine accuracy, intermethod agreement, and inter-reviewer agreement for multisequence magnetic resonance imaging (MRI) and 2-view orthogonal myelography in small-breed dogs with first-time intervertebral disk (IVD) extrusion.
Design—Prospective evaluation study.
Animals—24 dogs with thoracolumbar IVD extrusion.
Procedures—Each dog underwent MRI and myelography. Images obtained with each modality were independently evaluated and assigned standardized scores in a blinded manner by 3 reviewers. Results were compared with surgical findings. Inter-reviewer and intermethod agreements were assessed via κ statistics. Accuracy was assessed as the percentage of dogs for which ≥ 2 of 3 reviewers recorded findings identical to those determined surgically.
Results—Inter-reviewer agreement was substantial for site (κ = 0.70) and side of IVD extrusion (κ = 0.62) in T2-weighted magnetic resonance images and was substantial for site (κ = 0.72) and fair for side of extrusion (κ = 0.37) in myelographic images. Agreement for site between each modality and surgical findings was near perfect (κ = 0.94 and 0.88 for MRI and myelography, respectively). Intermethod agreement was substantial for site (κ = 0.71) and moderate for side of extrusion (κ = 0.40). Accuracy of MRI for site and side was 100% when results for T1-weighted, T2-weighted, and contrast-enhanced T1-weighted sequences were combined. Accuracy of myelography was 90.9% and 54.5% for site and side, respectively.
Conclusions and Clinical Relevance—Agreement between imaging results and surgical findings for identification of IVD extrusion sites in small-breed dogs was similar for MRI and myelography. However, MRI appeared to be more accurate than myelography and allowed evaluation of extradural compressive mass composition.
Objective—To develop and determine the feasibility of a novel minimally invasive technique for percutaneous catheterization and embolization of the thoracic duct (PCETD) in dogs and to determine thoricic duct TD pressure at rest and during short-term balloon occlusion of the cranial vena cava (CrVC).
Animals—Fifteen 7- to 11-month-old healthy mixed-breed dogs.
Procedures—Efferent intestinal lymphangiography was performed, and the cisterna chyli was punctured with a trochar needle percutaneously under fluoroscopic guidance. When access was successful, a guide wire was directed into the TD through the needle and a vascular access sheath was advanced over the guide wire. Thoracic duct pressure was measured at rest and during acute balloon occlusion of the CrVC. The TD was then embolized cranial to the diaphragm with a combination of microcoils and cyanoacrylate or ethylene vinyl alcohol.
Results—Successful puncture of the cisterna chyli with advancement of a wire into the TD was possible in 9 of 15 dogs, but successful catheterization was possible in only 5 of 9 dogs. Acute balloon occlusion of the CrVC led to a substantial TD pressure increase in 4 of 4 dogs, and embolization of the TD was successful in 4 of 4 dogs.
Conclusions and Clinical Relevance—PCETD can successfully be performed in healthy dogs; however, this minimally invasive technique cannot currently be recommended for routine treatment of chylothorax, in part because of the technically demanding nature of the procedure. An increase in jugular venous pressure led to an increase in TD pressure, potentially predisposing some dogs to developing chylothorax.
OBJECTIVE To evaluate peripheral blood and abdominal fluid variables as predictors of intestinal surgical site failure in dogs with septic peritonitis following celiotomy and closed-suction abdominal drain (CSAD) placement.
DESIGN Prospective study.
ANIMALS 26 dogs with septic peritonitis that underwent celiotomy and CSAD placement.
PROCEDURES Abdominal fluid and blood samples were collected prior to surgery and daily thereafter until CSAD removal. Abdominal fluid was collected through the CSAD. Analysis of all samples included pH, PCO2, PO2, PCV, WBC count, and total solids, glucose, lactate, and electrolyte concentrations. Abdominal fluid samples also underwent cytologic evaluation and bacterial culture, and the volume of fluid removed through the drain was recorded daily. The blood-to-fluid glucose and lactate differences, fluid-to-blood lactate ratio and blood-to-fluid WBC and neutrophil ratios were determined daily. Dogs were categorized into 2 groups on the basis of whether they had an uneventful recovery (UR) or developed postoperative septic peritonitis (POSP).
RESULTS 23 dogs had a UR and 3 developed POSP. On the third day after surgery, the abdominal fluid WBC count was significantly lower and the blood-to-fluid WBC and neutrophil ratios were significantly higher for dogs in the POSP group, compared with those for dogs in the UR group. None of the other blood and abdominal fluid variables assessed differed significantly between the 2 groups.
CONCLUSIONS AND CLINICAL RELEVANCE Results failed to identify any objective predictive indicators for POSP in dogs with CSADs. Use of blood-to-fluid WBC and neutrophil ratios as predictive indicators for POSP requires further investigation.
OBJECTIVE To describe the operative technique and perioperative outcome for laparoscopic-assisted splenectomy (LAS) in dogs.
DESIGN Retrospective case series.
ANIMALS 18 client-owned dogs.
PROCEDURES Medical records of dogs with naturally occurring disease of the spleen treated by means of LAS between 2012 and 2014 were reviewed. History, signalment, results of physical examination, results of preoperative diagnostic testing, details of surgical technique, intraoperative findings including results of abdominal exploration and staging, concurrent surgical procedures, complications, histopathologic diagnoses, duration of postoperative hospitalization, and perioperative outcome were recorded. The perioperative period was defined as the time from hospital admission for LAS until discharge or death (within the same visit).
RESULTS All dogs underwent initial abdominal exploration and staging via multiple 5-mm laparoscopic ports (n = 2) or a single commercially available multichannel port (16), followed by minilaparotomy with insertion of a wound retraction device, progressive exteriorization of the spleen, sealing of hilar vessels, and splenectomy. Splenectomy was performed for treatment of a splenic mass (n = 15), suspected neoplasia (2), or refractory immune-mediated disease (1). Median size (width × length) of splenic masses was 5 × 5 cm (range, 1.6 to 11.0 cm × 1.5 to 14.5 cm). Complications were limited to minor intraoperative hemorrhage in 1 dog; no patient required conversion to open laparotomy.
CONCLUSIONS AND CLINICAL RELEVANCE Results indicated that LAS was technically feasible in dogs and not associated with major complications. Further evaluation is required; however, in appropriately selected patients, LAS may offer the benefits of a minimally invasive technique, including a smaller incision and improved illumination and magnification during exploration and staging.
Objective—To compare the diagnostic quality of bronchoalveolar lavage (BAL) fluid acquired from healthy dogs by manual aspiration via polyethylene tubing (MAPT) and via suction pump aspiration (SPA) with a suction trap connection.
Animals—12 healthy adult Beagles.
Procedures—BAL was performed with bronchoscopic guidance in anesthetized dogs. The MAPT was performed with a 35-mL syringe attached to polyethylene tubing wedged in a bronchus via the bronchoscope's biopsy channel. The SPA was performed with 5 kPa of negative pressure applied to the bronchoscope's suction valve via a suction trap. The MAPT and SPA techniques were performed in randomized order on opposite caudal lung lobes of each dog. Two 1 mL/kg lavages were performed per site. Samples of BAL fluid were analyzed on the basis of a semiquantitative quality scale, percentage of retrieved fluid, and total nucleated and differential cell counts. Results were compared with Wilcoxon signed rank tests.
Results—Percentage of BAL fluid retrieved (median difference, 16.2%), surfactant score (median difference, 1), and neutrophil count (median difference, 74 cells/μL) were significantly higher for SPA than for MAPT. A higher BAL fluid epithelial cell score was obtained via MAPT, compared with that for samples obtained via SPA (median difference, 1).
Conclusions and Clinical Relevance—Results indicated that in healthy dogs, SPA provided a higher percentage of BAL fluid retrieval than did MAPT. The SPA technique may improve the rate of diagnostic success for BAL in dogs, compared with that for MAPT. Further evaluation of these aspiration techniques in dogs with respiratory tract disease is required.
Objective—To compare bronchoalveolar lavage (BAL) fluid obtained by manual aspiration (MA) with a handheld syringe with that obtained by suction pump aspiration (SPA) in healthy dogs.
Animals—13 adult Beagles.
Procedures—Each dog was anesthetized and bronchoscopic BAL was performed. The MA technique was accomplished with a 35-mL syringe attached to the bronchoscope biopsy channel. The SPA technique was achieved with negative pressure (5 kPa) applied to the bronchoscope suction valve with a disposable suction trap. Both aspiration techniques were performed in each dog in randomized order on opposite caudal lung lobes. Two 1 mL/kg aliquots of warm saline (0.9% NaCl) solution were infused per site. For each BAL fluid sample, the percentage of retrieved fluid was calculated, the total nucleated cell count (TNCC) and differential cell count were determined, and semiquantitative assessment of slide quality was performed. Comparisons were made between MA and SPA techniques for each outcome.
Results—1 dog was removed from the study because of illness. The mean percentage of fluid retrieved (mean difference, 23%) and median TNCC (median distribution of differences, 100 cells/μL) for samples obtained by SPA were significantly greater than those for samples obtained by MA.
Conclusions and Clinical Relevance—In healthy dogs, BAL by SPA resulted in a significantly higher percentage of fluid retrieval and samples with a higher TNCC than did MA. Further evaluation of aspiration techniques in dogs with respiratory tract disease is required to assess whether SPA improves the diagnostic yield of BAL samples.
To report the perioperative characteristics and outcomes of dogs undergoing laparoscopic-assisted splenectomy (LAS).
136 client-owned dogs.
Multicentric retrospective study. Medical records of dogs undergoing LAS for treatment of naturally occurring splenic disease from January 1, 2014, to July 31, 2020, were reviewed. History, signalment, physical examination and preoperative diagnostic test results, procedural information, complications, duration of hospitalization, histopathologic diagnosis, and perioperative outcomes were recorded. Perioperative complications were defined using the Veterinary Cooperative Oncology Group – Common Terminology Criteria for Adverse Events (VCOG-CTCAE v2) guidelines.
LAS was performed for treatment of a splenic mass (124/136 [91%]), immune-mediated disease (7/136 [5%]), splenomegaly (4/136 [3%]), or immune-mediated disease in conjunction with a splenic mass (1/136 [1%]). Median splenic mass size was 1.3 cm3/kg body weight. Conversion to open laparotomy occurred in 5.9% (8/136) of dogs. Complications occurred in 78 dogs, with all being grade 2 or lower. Median surgical time was 47 minutes, and median postoperative hospital stay was 28 hours. All but 1 dog survived to discharge, the exception being postoperative death due to a suspected portal vein thrombus.
In the dogs of this report, LAS was associated with low rates of major complications, morbidity, and mortality when performed for a variety of splenic pathologies. Minimally invasive surgeons can consider the LAS technique to perform total splenectomy in dogs without hemoabdomen and with spleens with modest-sized splenic masses up to 55.2 cm3/kg, with minimal rates of complications, morbidity, and mortality.