Effects of syringe type and storage temperature on results of blood gas analysis in arterial blood of horses.
BACKGROUND
Results of arterial blood gas analysis can be biased by pre-analytical factors, such as time to analysis, syringe type, and temperature during storage. However, the acceptable delay between time of collection and analysis for equine arterial blood gas remains unknown.


OBJECTIVE
Dedicated plastic syringes provide better stability of arterial blood gases than multipurpose plastic syringes.


METHODS
Eight mares, 1 stallion, and 1 gelding, ages 3 to 10 years old.


METHODS
Arterial blood samples were collected in a glass syringe, a plastic syringe designated for blood gas collection, and a multipurpose tuberculin plastic syringe. Blood samples were stored at ambient temperature or in iced water. For each sample, partial pressure of oxygen in arterial blood (PaO2), partial pressure of carbon dioxide in arterial blood (PaCO2), and pH were measured within a few minutes of collection and at 5, 20, 30, 60, 90, and 120 minutes after collection.


RESULTS
Collection into glass syringes stored in iced water provided adequate PaO2 results for up to 117 +/- 35 minutes, whereas blood collected in either of the plastic syringes resulted in a variation >10 mm Hg after 10 +/- 3 to 17 +/- 2 minutes, depending on the storage conditions. Plastic syringes kept at ambient temperature offered more stability for PaCO2 analysis because they could be stored up to 83 +/- 16 minutes without significant variations. Values of pH did not show variations more than 0.02 for the first hour, irrespectively of storage condition.


CONCLUSIONS
Glass syringes placed on ice are preferable for analysis of PaO2. Blood collected in plastic syringes should be analyzed within 10 minutes, irrespective of the storage temperature, to ensure the accuracy of PaO2 values.
Picandet
Valerie
V
Department of Clinical Sciences, Faculty of Veterinary Medicine, Université de Montréal, Saint-Hyacinthe, QC, Canada.
Jeanneret
Stephanie
S
Lavoie
Jean-Pierre
JP
D000818:Animals; D001784:Blood Gas Analysis / Q000295:instrumentation / Q000379:methods / Q000662:veterinary*; D001793:Blood Preservation / Q000295:instrumentation / Q000379:methods / Q000662:veterinary; D001800:Blood Specimen Collection / Q000295:instrumentation / Q000379:methods / Q000662:veterinary*; D002245:Carbon Dioxide / Q000097:blood; D005260:Female; D005898:Glass; D006736:Horses / Q000097:blood*; D006863:Hydrogen-Ion Concentration; D008297:Male; D010100:Oxygen / Q000097:blood; D010313:Partial Pressure; D010969:Plastics; D013594:Syringes / Q000662:veterinary*; D013696:Temperature; D013997:Time Factors
D010969:Plastics; D002245:Carbon Dioxide; D010100:Oxygen