No abstract

OBJECTIVE To compare the effect of blood collection by a push-pull technique from an indwelling IV catheter versus direct venipuncture on venous blood gas values before and after administration of alfaxalone or propofol to dogs. DESIGN Prospective randomized clinical study. ANIMALS 30 healthy client-owned dogs that weighed ≥ 10 kg (22 lb) and were anesthetized for elective surgical procedures. PROCEDURES All dogs were premedicated with methadone (0.5 mg/kg [0.2 mg/lb], IM), and 20 to 30 minutes later, anesthesia was induced with either alfaxalone (1 to 3 mg/kg [0.5 to 1.4 mg/lb], IV to effect; n = 15) or propofol (2 to 6 mg/kg [0.9 to 2.7 mg/lb], IV to effect; 15). Immediately prior to premedication and after anesthesia induction, paired blood samples were collected from the cephalic veins; 1 by direct venipuncture and 1 by use of a push-pull technique from a 20-gauge catheter. All blood samples underwent venous blood gas analysis immediately after collection. Results were compared between sample collection techniques before and after anesthesia induction and between anesthesia induction protocols. RESULTS All results were within established reference ranges. For many variables, statistically significant but clinically irrelevant differences were detected between samples collected by direct venipuncture and those collected by the push-pull technique but not between the 2 anesthesia induction protocols. CONCLUSIONS AND CLINICAL RELEVANCE Results indicated the push-pull technique was an acceptable method for collection of blood samples from dogs for venous blood gas analysis that could be used instead of direct venipuncture for patients with patent IV catheters.

The FloTrac/Vigileo overestimated CO values compared with LiDCO and the relative error was high, which makes this method unreliable for use in dogs.

OBJECTIVE To determine the prevalence of and covariates associated with the oculocardiac reflex (OCR) occurring in dogs during enucleations. SAMPLE 145 dogs that underwent enucleation at 2 veterinary teaching hospitals between January 2010 and June 2015. PROCEDURES Information was collected from the medical records of included dogs regarding age and body weight at hospital admission, breed (for classification of brachycephalic status), and whether they had received anticholinergic drugs or a retrobulbar nerve block (RNB) prior to enucleation. An OCR was considered to have occurred if there was a sudden decrease of ≥ 30% in heart rate from the baseline value (mean heart rate prior to the sudden decrease) during surgery in the absence of intraoperative administration of opioids or α2-adrenoceptor agonists. Associations were explored between the collected data and the prevalence of OCR by means of binomial logistic regression. RESULTS 4.8% (7/145) of dogs had an OCR noted during enucleation. Dogs that received a preoperative RNB (n = 82) had significantly lower odds of an OCR being observed than dogs that received no preoperative RNB (OR, 0.12). No association with OCR was identified for age or brachycephalic conformation or for preoperative administration of anticholinergic drugs. CONCLUSIONS AND CLINICAL RELEVANCE These findings suggested that preoperative administration of an RNB, but not preoperative administration of anticholinergic drugs, was associated with a lower prevalence of OCR in dogs during enucleations.

The aim of this prospective, randomized, nonblinded, controlled clinical trial was to compare mean arterial blood pressure (MAP) and heart rate (HR) during an intravenous bolus of three different balanced isotonic crystalloid solutions in euvolemic, anesthetized dogs with hypotension. Thirty healthy dogs (American Society of Anesthesiologists Physical Status I–II) weighing at least 15 kg that presented for elective orthopedic or dental surgical procedures at the Ryan Veterinary Hospital for Small Animals of the University of Pennsylvania were included in this study. Anesthetized hypotensive patients (defined as a MAP ≤ 65 mmHg), were administered an infusion of Lactated Ringer’s solution (LRS), Plasma-Lyte (PLYTE) or Canadian Plasma-Lyte (PLYTECA), selected at random. The infusion was administered over 15 min via a volumetric fluid pump. Differences in oscillometric MAP and HR between time points and across treatments were evaluated by mANOVA. Intravenous isotonic crystalloid infusions over 15 min did not significantly change MAP or HR in hypotensive dogs under general anesthesia. Neither LRS, PLYTE nor PLYTECA exacerbated hypotension or caused tachycardia.