Statstrip xpress lactate meter

RNs saw eligible patients within 2 h following ED triage, before any medical assessment or treatment (medication, fluids, oxygen) was initiated.
In this study, the StatStrip Xpress Lactate Meter capillary device (Nova Biomedical™) was used [47 ]. Analysis of its performance has previously demonstrated excellent correlation and concordance with the reference laboratory methods in an ICU population [39 (link)]. The device was calibrated every 2 days following the manufacturer’s instructions. Cut-offs for elevated lactate levels are not universally agreed upon [48 (link)]. In this study, blood lactate levels were considered normal when < 2.5 mmol/L, intermediate from 2.5 to 3.9 mmol/L, and high when ≥ 4.0 mmol/L. Three lactate level groups were also used in the study by Contenti et al. [45 (link)].

Plasma lactate level was measured using StatStrip Xpress Lactate Meter (Nova Biomedical, Waltham, MA, USA). Immediately after the final treadmill running exercise, a single drop of blood was obtained from the tail tip and applied onto a disposable strip for lactate measurement.

This study was approved by the Institutional Animal Care and Use Committee of the National Institute of Animal Science, ROK (JBNU IACUC No. NON2023‐123). All experimental procedures involving animals were conducted in strict accordance with relevant guidelines and regulations.
Blood was collected from 82 Korean indigenous cattle [grazing (n = 67) and indoor (n = 15)], which were raised on one farm in the ROK (Figure 1). Pregnant Korean beef cows aged 22−48 months were selected. The grazing group was fed forages of orchard grass and tall fescue, and the indoor group was fed concentrate and roughage with a dry matter intake of 5.5 kg/day (10% crude protein). Blood samples (10 mL) were taken from the jugular vein and divided into EDTA‐supplemented tubes (BD Vacutainer^®, Franklin Lakes, NJ, USA) and serum separation tubes (Vacutte serum tubes^®, Greiner Bio‐One, Austria).
All samples were placed on ice and immediately transported to the laboratory. On arrival, L‐lactate was measured using a portable lactate meter (Statstrip Xpress lactate meter; Nova Biomedical, Waltham, MA, USA), and the serum was separated by centrifugation at 3000 g for 10 min.
Cattle in the indoor group were usually pastured in the past; however, but these animals were housed in a barn for the past year. The grazing and indoor cattle were used as the experimental and control groups, respectively.