Plasma bicarbonate concentration, a parameter generated during arterial blood gas analysis, is essential to the assessment of patient acid-base status. Blood gas analyzers do not have the capacity to directly measure bicarbonate; instead, it is calculated from measured pH and pCO₂(a), using the Henderson-Hasselbalch...

Although arterial blood remains the gold standard sample for blood gas analysis, it is, compared with peripheral venous blood, a more difficult sample to obtain, and its collection is more painful and hazardous for the patient. These considerations have fuelled a growing interest in study aimed at establishing if...

The clinical value of any patient test result depends on the quality of the reference interval used for its comparison (interpretation), so that good laboratory medicine practice demands continuous review of reference intervals. There is a paucity of published study aimed at validating the health-associated reference...

A new parameter called critical reference change value (CrRCV) to be applied for the interpretation of serial measurements of cardiac troponin I (cTnI) is introduced. To illustrate the practical utility of CrRCV a set of clinical examples based on two consecutive cTnI results are presented. Thus three cTnI changes...

Arterial blood gas (ABG) analysis generates a number of parameters (listed in BOX 5) that together allow assessment of pulmonary gas exchange, blood oxygenation and acid-base balance. These physiological functions of the blood, respiratory and renal systems are disturbed in a range of respiratory and non-respiratory...

Emergency departments (ED) are challenged by increasing patient visits, overcrowding and prolonged length of stay (LOS). The cause of these problems is multifactorial. Delays in the laboratory are often perceived as contributing to delays in care and increased LOS. Implementation of selected point-of-care tests in...

Many hospitals have a pneumatic tube system (PTS) that is routinely used to transport blood samples rapidly to the central laboratory, but the notion that such systems can be used to transport samples destined for blood gas analysis is challenged by the results of a recent study.  This prospective study, focusing on...

Metabolic alkalosis is a disturbance of acid-base balance, with many possible causes, characterized by primary increase in blood bicarbonate (HCO₃) and pH. Hypoventilation is the normal compensatory respiratory response to metabolic alkalosis. This results in increased pCO₂ and, if the metabolic alkalosis is...

The necessary administration of image-enhancing agents to patients prior to radiological investigation is associated with risk of two serious adverse effects: nephrogenic systemic fibrosis (NSF) and contrast-induced nephropathy (CIN). The risk only applies to those patients with renal disease, either acute kidney...

Various guidelines and recommendations are available for the use of natriuretic peptides in the diagnosis of heart failure. As it is known that old age may lead to higher natriuretic peptide values in the absence of heart failure, it is relevant to decide whether to use age-dependent reference intervals for clinical...