Inter-instrumental comparison for the measurement of electrolytes in patients admitted to the intensive care unit

To investigate whether benchtop auto-analyzers (AAs) and arterial blood gas (ABG) analyzers, for measuring electrolyte levels of patients admitted to intensive care units (ICU), are equal and whether they can be used interchangeably. This study was conducted on 98 patients admitted to the ICU of the Institute of Medicine, Kathmandu, Nepal between 15 October and 15 December 2016. The sample for AA was collected from the peripheral vein through venipuncture, and that for ABG analyzer was collected from radial artery simultaneously. Electrolyte levels were measured with ABG analyzer in the ICU itself, and with benchtop AA in the central clinical biochemistry laboratory. The mean value for sodium by AA was 144.6 (standard deviation [SD] 7.63) and by ABG analyzer 140.1 (SD 7.58), which was significant ( -value