med. vet. / ACVIM-LA Resident University of Zurich Landquart, Graubunden, Switzerland
Abstract:
Background: Measurement of lactate concentration in blood [Lac]B and peritoneal fluid [Lac]PF is used to evaluate horses with gastrointestinal disease, although validation studies for POC analyzers are scarce. Hypothesis/
Objectives: Evaluation of the Accutrend Plus (AP), Lactate Pro 2 (LP2), Lactate Scout+ (LS+) and Eurolyser CUBE-VET (ECV) lactate analyzers by comparison with the RAPIDPoint 500 (RP) reference method and assessment of test repeatability. Animals: 96 adult horses with gastrointestinal disease.
Methods: [Lac]B and [Lac]PF were measured in parallel using all analyzers. Bland-Altman analysis was performed. Four samples with [Lac]B 0.95-4.26 mmol/L and three samples with [Lac]PF 3.80-6.21 mmol/L were measured 10 times in series and the coefficient of variation (CV) was calculated.
Results: The bias of AP was not significantly related to [Lac], whereas the bias of all other devices increased with [Lac]. Mean bias (95% limits of agreement) were as follows: [Lac]B AP 0.64 (-0.72 to 2.00)mmol/L, LP2 41.6 (-12.2 to 95.3)%, LS+ -1.4 (-44.7 to 41.9)%, ECV -14.9 (-85.7 to 55.8)%; [Lac]PF AP -0.82 (-2.59 to 0.95)mmol/L, LP2 81.5 (52.5 to 110.5)%, LS+ 12.6 (-30.1 to 55.3)%, ECV -9.9 (-77.9 to 58.1)%. The CV for repeated measurements was as follows: [Lac]B RP 7.8%, AP 22.5%, LP2 18.9%, LS+ 13.8%, ECV 7.0%; [Lac]PF RP 3.8%, AP 6.4%, LP2 1.7%, LS+ 4.9%, ECV 9.4%. Conclusion and clinical importance: AP, LS+ and ECV can be used in clinical practice for measurement of [Lac]B and [Lac]PF. The use of LP2 is not recommended because of consistent overestimation of [Lac]B and [Lac]PF.
