Assessment of acute moderate hyperglycemia on traditional and thromboelastometry coagulation parameters in healthy adult horses.

OBJECTIVE: To determine whether experimentally induced acute moderate hyperglycemia is associated with coagulation activation in healthy adult horses. DESIGN: Prospective experimental study. SETTING: University veterinary teaching hospital. ANIMALS: Six healthy adult horses. INTERVENTIONS: Hyperglycemia (10.0-13.3 mmol/L [180-240 mg/dL]) was induced and maintained for 6 hours using a hyperglycemic clamp technique. Blood glucose concentrations were assessed using a point of care (POC) glucometer at 10- and 20-minute intervals throughout the hyperglycemic clamp procedure. Platelet count, fibrinogen concentration, prothrombin time (PT), activated partial thromboplastin time (aPTT), thrombin antithrombin complex level (TAT), and thromboelastometry (TEM) were determined before and after jugular catheter placement, prior to glucose administration, and at 3 and 6 hours of sustained hyperglycemia. Data were analyzed by repeated measures analysis of variance with significance defined as P < 0.05. MEASUREMENTS AND MAIN RESULTS: All horses maintained blood glucose concentration >10.0 mmol/L (>180 mg/dL) throughout the duration of the hyperglycemic clamp with a mean concentration of 11.9 ± 0.3 mmol/L [216 ± 6 mg/dL] as measured by the POC glucometer. No significant difference was found for any evaluated parameter associated with sustained hyperglycemia. Intravenous catheter placement resulted in a significant increase in mean TAT (0.8 ± 0.3 µg/L pre-catheter, 2.3 ± 0.8 µg/L post-catheter; P = 0.008). CONCLUSIONS: Acute, moderate hyperglycemia in healthy adult horses does not have a detectable effect on coagulation based on evaluated parameters. Jugular catheter placement results in a transient increase in thrombin generation as determined by increased TAT concentrations.

Assessment of a point-of-care lactate monitor in emergency admissions of adult horses to a referral hospital.

BACKGROUND: Blood lactate concentration [LAC] is considered a useful indicator of disease severity in horses. Agreement of point-of-care (POC) lactate monitors with laboratory standards has not been established for clinically abnormal horses. HYPOTHESIS: It was hypothesized that results from a POC lactate monitor would be in agreement with a laboratory-based measurement of [LAC]. ANIMALS: The study included adult horses presented for emergency evaluation. METHODS: A prospective observational study was performed. [LAC] was measured with whole blood (AWB) and plasma (APL) by means of a POC monitor (Accutrend) and compared with results from whole blood measured by a laboratory blood gas analyzer (NOVA). RESULTS: Samples from 221 horses were used to compare the 2 lactate measurement techniques. Agreement (p +/- SE) was closest between APL and NOVA (0.97 +/- 0.01); an average observed difference of 0.15 +/- 0.89 (mean +/- SD) and 95% limits of agreement (LOA) -1.89, 1.59 also were found. Agreement was preserved and 95% LOA further decreased in horses with NOVA [LAC] of <5 mM and PCV <40%. Agreement was modest when testing whole blood samples on the POC monitor with increased 95% LOA. CONCLUSIONS AND CLINICAL IMPORTANCE: Results indicate close agreement between NOVA and the POC monitor when [LAC] was measured with plasma. Results were less consistent at higher [LAC] but sufficiently reliable to follow trends. Although whole blood may be used with the POC monitor to identify clinically important hyperlactatemia, results may be insufficiently reliable to monitor trends.