Comparison of two blood sampling techniques for the determination of coagulation parameters in the horse: Jugular venipuncture and indwelling intravenous catheter

Coagulation Profile of the Healthy Miranda's Donkey

Miranda's donkey, originating in northern Portugal, is an autochthonous breed that is deeply intertwined with the region's culture and economy. Knowledge of the physiological characteristics of the breed is important for its preservation, and several studies have been carried out, but none have focused on its coagulation profile. The aim of this study was to establish reference intervals (RIs) for coagulation in healthy Miranda's donkey and to assess the influence of sex and age. Blood samples from 75 clinically healthy animals were analyzed for seven coagulation parameters: four using IDEXX ProCyte Dx and three using Start® 4-Diagnostica-Stago. The RI values were calculated following the ASVCP guidelines and with the Reference Advisor V.2.1 software. To analyze the influence of sex and age, SPSS version 29 was used. No significant differences were found between sexes (p > 0.05), but statistically significant differences were found between ages (p < 0.05) for platelet count and plateletcrit (both higher in young animals). The RIs described here can help monitor health and guide the diagnosis and treatment of diseased Miranda's donkeys, contributing to their preservation. Our study encourages further research on coagulation in donkeys and the use of different methodologies to obtain information for veterinarians working with this species.

Performance of 3 mL versus 5 mL Discarded Volume for Blood Sampling from Central Venous Access Device

Background  Central venous access devices (CVAD) are an essential part of safe practices in critical care, which enable effective venous access and help in avoiding repeated venipuncture. Discard method is widely practiced for blood sampling. A single occasion of blood sampling may cause minimal blood loss; however, the cumulative volume sequential sampling may become clinically significant. The study aims to reduce diagnostic blood loss, ensuring that the subsequent blood sample is not diluted or contaminated by residual intraluminal fluid. Patients and Methods  Within-subjects comparative design was adopted for 64 adult patients in the medical intensive care unit of a tertiary hospital. Two blood samples, using 3 mL and 5 mL discarded volume methods, were collected from each patient. Six serum parameters were measured on each of the paired samples and compared. Statistical Analysis Used  Paired t -test and Wilcoxon signed rank test were used for comparing the two methods. Bland-Altman plot analysis and intraclass correlation were used for clinically meaningful analysis. Results  When tested for fixed bias, there is no statistically significant difference between the methods. Potassium and creatinine levels showed significant proportional bias. The agreement limits of sodium, potassium, creatinine, and direct bilirubin were outside the clinically accepted interval, but the proportion of samples outside these intervals was less than 10%. All serum parameters showed excellent reliability, except for sodium which demonstrated good reliability. Conclusions  The practice of discarding 3 mL of blood for discard method is suggested, instead of the standard 5 mL to reduce iatrogenic blood loss. Thus, nurses in critical care are uniquely positioned to limit the diagnostic blood loss while obtaining blood samples.

Venous blood gas parameters, electrolytes, glucose and lactate concentration in sick neonatal foals: Direct venipuncture versus push-pull technique

BACKGROUND

Blood collection by indwelling intravenous catheter (IVC) avoids repeated venipuncture, which could cause thrombophlebitis risk, anxiety and pain in patients.

OBJECTIVES

To compare blood gas parameters, electrolytes, glucose, lactate and haematocrit concentration obtained from venous blood samples collected via a jugular IVC by push-pull (PP) technique to those obtained by venipuncture in hospitalised foals, at the time of catheter placement (T0) and 24 hours after the beginning of intravenous therapy (T24).

STUDY DESIGN

Prospective observational study.

METHODS

Paired blood samples were drawn from hospitalised foals at T0 and T24. In each foal, one venous blood sample was collected via IVC by the following PP technique: 2.4 mL of blood was aspirated and immediately reinfused through the catheter three times consecutively, then 1 mL of blood was collected using a 1 mL heparinised syringe. Thereafter, another sample was collected by direct venipuncture of the contralateral jugular vein, with an identical 1 mL heparinised syringe, with a 1-inch, 20-G needle. All samples were analysed with an automated blood gas analyser within 10 minutes of collection. The agreement between the two techniques was assessed by Bland-Altman analysis and intraclass correlation coefficient (ICC).

RESULTS

The level of agreement of blood gas values obtained by the two different techniques was high with very small bias and clinically acceptable ICC (>0.907 at T0; >0.794 at T24) for all variables, except for haematocrit (bias -3.52 at T0; -2.44 at T24) and PvO₂ at T0 and T24 (ICC 0.669 and 0.733, respectively).

MAIN LIMITATIONS

Potential sub-clinical catheter-related complications were not investigated by ultrasound or bacterial culture of the catheter; short duration of the study.

CONCLUSIONS

PP technique appears to be acceptable for collection of blood samples for venous blood gas parameters, as well as electrolytes, glucose and lactate in sick neonatal foals.

Coagulation Assessment in the Equine Patient

Horses with clinical signs of unprovoked or excessive hemorrhage should be evaluated for underlying platelet defects or coagulopathies. This article provides an overview of preliminary screening and definitive tests to assess coagulation and identify hemostatic defects in horses, as well as a review of the hemostatic disorders most frequently encountered in clinical practice.