Influence of three anesthetic protocols on glomerular filtration rate in dogs

OBJECTIVE: To investigate renal function in clinically normal dogs when awake and during anesthesia with medetomidine; xylazine, ketamine, and halothane (XKH) combination; or propofol. ANIMALS: 10 adult female Beagles. PROCEDURES: At intervals of 15 days, dogs were administered medetomidine (0.05 mg/kg, IV); XKH combination (xylazine [1 mg/kg, IV], ketamine [5 mg/kg, IV], and halothane [1% end-tidal concentration]); or propofol (6 mg/kg, IV) to induce anesthesia or no treatment. Glomerular filtration rate was assessed on the basis of renal uptake (RU; determined via renal scintigraphy) and plasma clearance (CL) of technetium 99m-labeled diethylenetriamine pentaacetic acid ((99m)Tc-DTPA). RESULTS: In awake dogs, mean +/- SEM RU was 9.7 +/- 0.4% and CL was 3.86 +/- 0.23 mL/min/ kg. Renal uptake and CL of (99m)Tc-DTPA were not significantly modified by administration of XKH (RU, 11.4 +/- 0.9%; CL, 4.6 +/- 0.32 mL/min/kg) or propofol (RU, 9.7 +/- 0.3%; CL, 3.78 +/- 0.37 mL/min/kg). Half-life elimination time of plasma (99m)Tc-DTPA decreased significantly in XKH-anesthetized dogs, compared with the value in awake dogs (14.4 minutes and 28.9 minutes, respectively). However, glomerular filtration rate was significantly decreased by administration of medetomidine (RU, 3.9 +/- 0.1%), and the time to maximum kidney activity was significantly increased (867 +/- 56 seconds vs 181 +/- 11 seconds without anesthesia). CONCLUSIONS AND CLINICAL RELEVANCE: Results indicated that anesthesia with propofol or an XKH combination did not alter renal function in healthy Beagles, but anesthesia with medetomidine decreased early RU of (99m)Tc-DTPA.     

Suspect osteogenesis imperfecta in a male kitten

A 4.5-month-old, male domestic shorthair was presented with bilateral femoral fractures after falling from a low height. Radiographs revealed reduced radio-opacity and thin cortices of all long bones. A presumptive diagnosis of osteodystrophy, secondary to osteogenesis imperfecta, was made on postmortem examination.     

Efficacy of topical eprinomectin in the treatment of Chorioptes sp. infestation in alpacas and llamas

Chorioptes sp. mite infestation is increasingly recognized as a cause of skin disease in New World camelids and there is a need for an effective treatment protocol to eliminate herd infestation. In this field trial, eprinomectin applied topically at the rate of 0.5 mg kg(-1) weekly for 10 weeks was found to be ineffective in a herd of 12 llamas and 16 alpacas.     

Postenucleation orbital sialocele in a dog associated with prior parotid duct transposition

An orbital sialocele developed in a dog following enucleation for protracted glaucoma. This eye had historically been treated for keratoconjunctivitis sicca by parotid duct transposition approximately 5 years previously, and the duct was ligated distally at the time of enucleation. One month following enucleation, the dog presented with a fluctuant conical-shaped swelling ventrolateral to the orbital socket. Surgical exploration revealed a dilated, fibrotic distal portion of the previously transposed parotid duct, and saliva, within the enucleated orbit. The distal portion of the duct and saliva-containing tissues from within the orbit were excised. The remaining proximal normal portion of the parotid duct was re-routed into the oral cavity. Clinicopathologic and histologic examination of the excised orbital contents and dilated portion of duct revealed a sterile sample of saliva and moderate chronic periductal fibrosis. At a 6-month re-evaluation there was no evidence of recurrence of the sialocele, and the parotid duct was functional.     

Plasma fentanyl concentrations in awake cats and cats undergoing anesthesia and ovariohysterectomy using transdermal administration

Objective To measure the plasma fentanyl concentrations achieved over time with transdermal fentanyl patches in awake cats and cats undergoing anesthesia and ovariohysterectomy. Study design Randomized prospective experimental study. Animals Twenty‐four purpose‐bred cats. Methods Cats were randomly assigned to three groups for Part I of a larger concurrent study. Group P received only a 25 μg hour^?1 transdermal fentanyl patch. Group P/A received the patch and anesthesia. Group A received only anesthesia. After a minimum 1‐week washout period, the cats were randomly reassigned to two groups for Part II of the larger study. Group P/A/O received the patch, anesthesia and ovariohysterectomy. Group A/O received anesthesia and ovariohysterectomy. Patches were left in place for 72 hours and plasma samples were obtained for fentanyl analysis while the patches were in place, and for 8 hours after patch removal for cats in Group P, P/A, and P/A/O. Results The 25 μg hour^?1 transdermal fentanyl patches were well tolerated by the cats in this study (mean body weight of 3.0 kg) and no overt adverse effects were noted. Mean plasma fentanyl concentrations over time, mean plasma fentanyl concentrations at specific times (8, 25, 49, and 73 hours after patch placement), time to first detectable plasma fentanyl concentration, time to reach maximum plasma fentanyl concentration, maximum plasma fentanyl concentration, mean plasma fentanyl concentration from 8 to 73 hours, elimination half‐life, and total area under concentration (AUC) were not statistically different among the groups. Conclusions Halothane anesthesia and anesthesia/ovariohysterectomy did not significantly alter the plasma fentanyl concentrations achieved or pharmacokinetic parameters measured, when compared with awake cats. There was a high degree of individual variability observed both within and between groups of cats in parameters measured. Clinical significance The high degree of variability observed suggests that careful observation of cats with fentanyl patches in place is required to assess efficacy and any potential adverse effects. Anesthesia and anesthesia/ovariohysterectomy do not appear to alter plasma fentanyl concentrations achieved by placement of a 25 μg hour^?1 transdermal fentanyl patch when compared to cats not undergoing these procedures.     

Effects on plasma endotoxin and eicosanoid concentrations and serum cytokine activities in horses competing in a 48-, 83-, or 159-km endurance ride under similar terrain and weather conditions

OBJECTIVE: To determine plasma endotoxin concentration in horses competing in a 48-, 83-, or 159-km endurance race and its importance with regard to physical, hematologic, or serum and plasma biochemical variables. ANIMAL: 3 horses. PROCEDURE: Weight and rectal temperature measurements and blood samples were obtained before, during, and after exercise. Blood samples were analyzed for plasma endotoxin concentration; serum antiendotoxin antibody titers; thromboxane B2 (TxB2) and 6-keto-prostaglandin F1alpha (PGF1alpha) concentrations; tumor necrosis factor alpha (TNFalpha) and interleukin-6 (IL-6) activities; WBC, plasma protein, lactate, serum electrolyte, and calcium concentrations; PCV; and creatine kinase activity. RESULTS: Detection of plasma endotoxin increased during exercise for horses competing at all distances but occurred more frequently in the 48- and 83-km groups. Plasma lactate concentration was significantly greater when endotoxin was concurrently detected. Endotoxin in plasma was not significantly associated with success of race completion. Plasma TxB2 and PGF1alpha concentrations and serum IL-6 activity significantly increased with exercise. Horses that had an excellent fitness level (as perceived by their owners) had greater decreases in serum antiendotoxin antibody titers during exercise than did horses perceived as less fit. In horses with better finish times, TxB2 and PGF1alpha concentrations were significantly greater and TNFalpha activity was significantly less than that of slower horses. CONCLUSIONS AND CLINICAL RELEVANCE: Endotoxemia developed during endurance racing, but was significantly correlated with increased plasma lactate concentration and not with other variables indicative of endotoxemia. Plasma TxB2 and PGF1alpha concentrations and serum TNFalpha activity may be associated with performance success.