Statstrip xpress lactate hospital meter

Blood spots were prepared on filter paper from the blood sample taken from each patient and subsequently processed at the Malaria Research Centre, Universiti Malaysia Sarawak. DNA was extracted from the blood spots using InstaGene™^{42 (link)} and nested PCR assays for identification of malaria species with primers for P. falciparum, P. malariae, P. vivax, P. ovale, P. knowlesi, P. cynomolgi and P. inui were utilised as described previously^{1 (link),43 (link),44 (link)}. Each P. knowlesi subpopulation was identified using cluster-specific PCR assays^{13 (link)}. Parasite counts were determined using the average readings of two independent experienced laboratory technicians derived from the number of parasites per 500 white cells, adjusted by the total white cell count for each patient.
Haematological profiles on-site at the hospital laboratory were determined using semi-automated methods (Mek-6410 K, Nihon Kohden Corporation, Japan). Citrated blood samples were analysed for coagulation studies with Sysmex® Ca 500v (Kobe, Japan). Biochemistry tests were conducted using Beckman-Coulter™ AU480 and a point-of-care meter was used for determination of lactate levels (StatStrip Xpress® Lactate Hospital Meter, Nova Biomedical, USA).

Blood pressure was measured using a hemodynamic monitor (Power Lab, AD Instruments, Colorado Springs, CO) connected to the femoral artery. Blood levels of oxygen (O₂), carbon dioxide (CO₂), bicarbonate (HCO₃), base excess (BE) and pH were quantified by sampling and measuring 200 μl of arterial blood with a blood gas analyzer (Stat Profile Critical Care Xpress, NOVA Biomedical, Waltham, WA) and lactate using a handheld testing system (Stat Strip Xpress Lactate Hospital Meter, NOVA Biomedical, Waltham, WA). The manual microhematocrit method was used to determine the hematocrit (Hct) and a refractometer for the plasma protein concentration.