Three parameters generated during blood gas analysis, pH, pCO₂ and bicarbonate, provide the means for assessment of patient acid-base status, which is frequently disturbed in the acutely/critically ill. Four broad classes of acid-base disturbance are recognized: metabolic acidosis, respiratory acidosis, metabolic...

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, ...

This recently published case study report provides a reminder that blood gas analysis plays an important role in the emergency room assessment of unconscious patients and that disturbance of acid-base homeostasis can be attributable to ingestion of toxic chemicals. The case concerns a 37-year old non-insulin dependant ...

Blood gas analysis involves measurement of three parameters: pH, partial pressure of carbon dioxide (pCO₂) and partial pressure of oxygen (pO₂). Derived (calculated from these measured values) parameters also generated during blood gas analysis include: bicarbonate (HCO₃) concentration, base excess (BE) and oxygen...

The maintenance of blood pH within normal limits (7.35-7.45), called acid-base homeostasis, is a complex synergy involving three organs (lungs, kidneys and brain) as well as chemical buffers in blood and blood cells (erythrocytes). This vital physiologic process is the subject of a recent expert review article,...

Health demands that blood pH is maintained within narrow limits (7.35-7.45). Acidosis (i.e. pH <7.35) is a common feature of many acute/critical conditions that warrant admission to intensive care. pH <6.8 is commonly reported in medical texts as incompatible with life, but there are rare individual case reports of...

A clinical requirement for determination of the pH and base deficit (BD) of umbilical-cord arterial blood has ensured a role for the blood gas analyzer in the delivery suite of obstetric units.  The principal objective of this testing in the minutes immediately after birth is to identify those babies who have been...

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 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...