This second of two articles on understanding the clinical value of measuring urea concentration explores the clinical value of simultaneous measurement of urea and creatinine and calculating the urea:creatinine ratio. The article discusses the causes of increased and decreased ratio as well as the clinical application ...

Bacterial infections are one of the major reasons for patients presenting to the ED - and the main cause of death in elderly patients. It is important to identify elderly patients with bacterial infections early and initiate treatment in the ED for a better outcome. However, an infection in an elderly patient can be...

This first of two articles on understanding the clinical value of measuring urea concentration dives into the physiological topics, such as urea production and renal processing of urea as well as the causes of increased and reduced urea concentration. Kidney disease is associated with reduced urea excretion and...

For patients presenting to the ED with symptoms of a suspected infection, measuring procalcitonin (PCT) is a useful diagnostic tool to identify bacterial infections, such as sepsis, allowing for early initiation of proper antibiotic treatment. In assessing the severity of sepsis, serum PCT levels are an important...

This first of two articles on method comparison studies gives some key concepts related to the design of the method comparison study, data analysis and graphical presentation, stressing the importance of a well-designed and carefully planned experiment using adequate statistical procedures for data analysis when...

When a new D-dimer method is evaluated, it’s typically compared to an established D-dimer method using both an analytical and a clinical comparison. Analytical comparisons should be discouraged, as they do not give any useful information about the potential clinical usability of the assay. D-dimer assay comparisons...

The measurement of the parameters pH, pCO₂ and pO₂ is vulnerable to a number of preanalytical errors and this article shares practical tips to help avoid these errors, ensuring that the results of analysis accurately reflect the patient’s acid-base and oxygenation status. The tips include the removal of air bubbles, ...

The process of blood gas and pH measurement involves preheating the arterial blood sample to normal body temperature (37 °C) prior to measurement of pH, partial pressure of oxygen (pO₂) and partial pressure of carbon dioxide (pCO₂). This ensures that results reflect in vivo temperature condition. A minority of...

Point-of-care testing (POCT) covers a broad range of pathology and non-pathology testing. The volume of POCT is rapidly increasing with an annual growth rate of 12-15 %. By virtue of its compactness, portability, and the feasibility of operation by non-laboratory personnel, where fast and accurate testing methods and...

The significance of good practice during the preanalytical phase of clinical laboratory investigation cannot be overemphasized. One aspect of the preanalytical phase – the transport of samples – is considered here; in particular the transport of samples via pneumatic tube systems. This is an update of a previous...