Evaluation of hemostatic derangements associated with canine anaphylaxis and the relationship to syndrome severity

Objective

To describe hemostatic derangements associated with canine anaphylaxis and to assess for association with syndrome severity.

Design

Prospective observational study.

Setting

University teaching hospital.

Animals

Twenty-seven client-owned dogs, recruited from November 2018 to January 2022, diagnosed with anaphylaxis of varying severity were included. Study inclusion required presentation <6 hours after initiation of clinical signs, no medications or history of illness within the prior 2 weeks, lack of comorbidities expected to affect hemostasis, and lack of a disease state that could alternatively explain the clinical presentation.

Interventions

Blood samples were collected within the first hour of presentation for CBC, serum biochemistry, prothrombin time (PT), activated partial thromboplastin time (aPTT), and viscoelastic coagulation testing for use with a cartridge-based point-of-care device.

Measurements and main results

Clotting time and clot formation time were prolonged, alpha angle and maximum clot firmness were decreased, PT and aPTT were prolonged, and platelet counts were lower in severe cases compared to mild and moderate cases. There were no differences for any parameter between mild and moderate cases. The presence or absence of abdominal effusion was not associated with hemostatic status.

Conclusions

Global hemostatic derangements consistent with hypocoagulability are a prominent feature of severe anaphylaxis in dogs and should be considered for routine evaluation.     

Stress and glycemic responses to postprandial interval and feed components in exercising horses

Six Thoroughbred geldings were used in a Latin squaredesign to determine the effects of three feeding regimens and two postprandial intervals on stress parameters during rest, exercise, and recovery. Each horse was randomly assigned to one of six treatments on six sampling days. The three feeding regimens consisted of a fasting regimen in which no feed was offered, or an isoenergetic (4.1 Mcal DE) meal of either corn or alfalfa. One or 4 h after feeding, a standardized exercise test (SET) was imposed on all horses. The SET consisted of three 10-min periods each of saddling, walking to the arena, and warm-up (walking and trotting), followed by three bouts of progressively more intense galloping at heart rates of 130–140 (10 min), 150–160 (10 min), and 170–180 bpm (5 min), respectively. Blood was sampled via jugular catheters from 0630 to 1500, including the 55-min SET. Analysis of variance by repeated measures within either the 1- or 4-h protocol showed no differences between dietary treatments for glucose concentration; differences due to sampling time were shown for concentrations of glucose, lactate, cortisol, α₁-acid glycoproteins (AGP), and the neutrophil to lymphocyte ratio (N:L). In both the 1- and 4-h protocols, glucose concentrations decreased precipitously in cornfed horses at the onset of the SET, but rebounded at the termination of the galloping. Plasma glucose concentrations in fasting and alfalfa-fed horses decreased slightly and then gradually increased throughout the SET. Serum cortisol and plasma lactate concentrations did not differ (P >.05) between dietary treatments, but increased concentrations were detected during the SET in both the 1- and 4-h protocols. The AGP concentration and N:L did not differ (P>.05) due to dietary treatments; however, AGP concentrations marginally increased (P<.10) from prefeeding to early recovery during the 1-h but not the 4-h protocol. The N:L increased (P<.05) in response to exercise; elevated values were detected in early recovery.