The 1999 US Institute of Medicine report "To Err is Human: Building a Safer Health Care System" provided an influential wake-up call for healthcare workers concerning the frequency of preventable medical errors. Initiatives over the past decade aimed at improving the safety of patient-sample testing represent just...

Arterial blood gas analysis is used to assess and monitor patient acid-base status. Disturbance of acid-base balance is classified to one of four main types depending on the pH, pCO₂(a) and bicarbonate results generated during blood gas analysis; the four types are respiratory acidosis, respiratory alkalosis,...

Mechanical ventilation is necessary for survival of patients with acute respiratory distress syndrome (ARDS). It was once supposed that ventilation should be adjusted to maintain pCO₂(a) within the normal range but this degree of mechanical ventilation can result in further damage to the lungs. Less aggressive (low...

Pulse oximetry provides the means for continuous non-invasive monitoring of blood oxygenation by measuring % oxygen saturation (SpO₂). This safe, easy and convenient method of monitoring oxygenation status is ubiquitous in clinical medicine and is now a routine part of the overall assessment and monitoring of all...

Increasing obesity is associated with worsening arterial blood gases (pO₂(a) and pCO₂(a)). That is the headline finding of a recent cross-sectional study of morbidly obese individuals with apparently normal lung function and no respiratory disease.  The study population comprised 114 women and 35 men with a mean (SD) ...

Hypokalemia, one of the most common electrolyte disturbances, is diagnosed if plasma potassium concentration is less than 3.5 mmol/L. Mild hypokalemia (plasma potassium 3.0-3.5 mmol/L) is usually asymptomatic, but greater degree of hypokalemia can result in signs and symptoms that reflect the fundamental role of...

Most babies born prematurely have respiratory problems and require assisted ventilation and oxygen therapy to ensure adequate tissue oxygenation. Supplemental oxygen is a double-edged sword for these babies because although of life-preserving benefit, oxygen in excess is toxic.  The principal (but not the only)...

In the intensive care unit blood is frequently sampled for arterial blood gases via an indwelling arterial catheter. Around a third of critically ill patients have such catheters inserted; they allow not only easy access for blood sampling but also continuous monitoring of blood pressure. In a short editorial the...

If the results of a recent New Zealand study are representative, there is room for improvement in the quality of blood gas test result interpretation among emergency-room medical staff. A total of 80 emergency-room doctors (37 consultants and 43 emergency-medicine trainees) voluntarily submitted themselves for a...

Many drugs, when taken in overdose, can deleteriously affect acid-base balance, leading to abnormal arterial blood gas (ABG) results. Aspirin is one such, and perhaps because of its easy availability, one of the most common of all drugs to be taken in overdose. Salicylate (aspirin) poisoning thus represents the most...