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...

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...

Clinical sensitivity, clinical specificity and predictive values are frequently used as performance measure for a biochemistry assay. When D-dimer assay performance is presented, emphasis is often on the negative predictive value (NPV). However, predictive values are greatly influenced by the prevalence of the...

With the ultimate goal of improving patient care, adoption of point-of-care testing (POCT) continues to grow at a high rate. The ability to deliver fast and reliable results near the patient is a key driver for improving patient outcomes and optimizing clinical workflow. While there are many advantages, controlling...

Plasma sodium concentration is measured with an ion-specific electrode (ISE) using either an undiluted sample (direct ISE) or diluted sample (indirect ISE).  This is the second of two linked articles highlighting the spurious sodium values that can occur if an indirect ISE method is used to analyze plasma samples with ...

Reprinted from Ann Lab Med 2014 Sep; 34(4):263-73. Procalcitonin (PCT) is used as a biomarker for the diagnosis of sepsis, severe sepsis and septic shock. At the same time, PCT has also been used to guide antibiotic therapy. This review outlines the main indications for PCT measurement and points out possible...

This article first appeared in Pathology in Practice (Hobba H, Silver L. Evolution of POC testing. Pathology in Practice 2013; 14 [2]: 63) and is reproduced here by kind permission (www.pathologyinpractice.com). © 2013 kdm communications limited Point-of-care (POC) testing has allowed the pathology department in...

Disturbance of sodium balance is a common occurrence among hospitalized patients that can, if not identified and treated, cause significant morbidity; severe disturbance is potentially lethal. So estimation of plasma sodium concentration is one of the most frequently requested blood tests.  Historically, plasma sodium ...

Sampling capillary blood from the fetal scalp during labor of pregnancy, in order to determine its pH, was introduced to obstetric care in the late 1960s.  Despite current skepticism surrounding its utility, most notably in the US, fetal-scalp blood sampling (FSBS) is still considered a useful fetal monitoring test...

This short review aims to put the diagnostic options provided by state-of-the-art POCT  technology into perspective with the clinical challenges faced by physicians treating patients presenting with acute dyspnea.  Natriuretic peptides, hemoglobin, D-dimers and venous blood gases play a key role in the early...