Stevenson Connie K, Kidney Beverly A, Duke Tanya, Snead Elisabeth C R, Jackson Marion L
Department of Veterinary Pathology, Western College of Veterinary Medicine, Saskatchewan, Canada.
Vet Clin Pathol. 2007 Sep;36(3):261-6. doi: 10.1111/j.1939-165x.2007.tb00221.x.
Lactate concentrations are increasingly quantified in dogs using point-of-care instruments, but often without canine-specific method evaluation and instrument-specific reference intervals.
The objectives of this study were to 1) determine the precision of the Accutrend (Roche Diagnostics) for lactate determination in dogs, 2) determine the accuracy of the Accutrend using the Rapidlab 865 (Bayer Diagnostics) as the reference method, and 3) establish and compare reference intervals for lactate concentration in clinically healthy dogs for both instruments.
Precision was evaluated using low and high control materials, and variable (1 drop) and fixed (25 microL) sample volumes. Accuracy was determined by comparing lactate concentrations obtained with the Accutrend with those from the Rapidlab 865 in 273 heparinized canine jugular venous blood samples from 100 clinically healthy dogs and 107 systemically ill dogs (173 samples). Lactate reference intervals were established for both analyzers using data from the 100 clinically healthy dogs.
The precision of the Accutrend was good (coefficients of variation, < or = 5.3%) for 25-microL samples but not when a drop was used. Lactate concentrations obtained on the Accutrend correlated poorly with those from the Rapidlab 865 (r = 0.864, mean bias = 0.66 mmol/L, 95% confidence interval [CI] = 0.57-0.76 with 95% limits of agreement = -0.87 (lower limit, 95% CI = -1.03 to -0.71) and 2.20 (upper limit, 95% CI = 2.04 to 2.36). The reference interval for canine lactate concentration on the Accutrend was 1.2-3.1 mmol/L compared with 0.46-2.31 mmol/L on the Rapidlab.
Although precision was good with fixed sample volumes, blood lactate concentrations obtained on the Accutrend were significantly different than those on the Rapidlab 865, with systematic and random errors resulting in a positive bias. Further evaluation of the Accutrend is required before its use in dogs can be recommended.
目前越来越多地使用即时检测仪器对犬类的乳酸浓度进行定量检测，但通常未对犬类特异性方法进行评估，也未建立仪器特异性参考区间。
本研究的目的是：1）确定罗氏诊断公司的Accutrend血糖仪检测犬类乳酸浓度的精密度；2）以拜耳诊断公司的Rapidlab 865血糖仪作为参考方法，确定Accutrend血糖仪的准确性；3）为两种仪器建立并比较临床健康犬类乳酸浓度的参考区间。
使用低、高浓度质控品，以及可变（1滴）和固定（25微升）样本体积评估精密度。通过比较100只临床健康犬和107只全身患病犬（共173份样本）的273份肝素化犬颈静脉血样本中，Accutrend血糖仪与Rapidlab 865血糖仪测得的乳酸浓度，确定准确性。利用100只临床健康犬的数据，为两种分析仪建立乳酸参考区间。
对于25微升样本，Accutrend血糖仪的精密度良好（变异系数≤5.3%），但使用一滴血样本时精密度不佳。Accutrend血糖仪测得的乳酸浓度与Rapidlab 865血糖仪测得的结果相关性较差（r = 0.864，平均偏差 = 0.66毫摩尔/升，95%置信区间[CI] = 0.57 - 0.76，95%一致性界限 = -0.87（下限，95% CI = -1.03至 -0.71）和2.20（上限，95% CI = 2.04至2.36）。Accutrend血糖仪检测犬类乳酸浓度的参考区间为1.2 - 3.1毫摩尔/升，而Rapidlab血糖仪为0.46 - 2.31毫摩尔/升。
虽然固定样本体积时精密度良好，但Accutrend血糖仪测得的血乳酸浓度与Rapidlab 865血糖仪测得的结果存在显著差异，系统误差和随机误差导致正偏差。在推荐将Accutrend血糖仪用于犬类检测之前，需要进一步评估。
