Hemolysis causes clinically significant bias in four of twelve parameters generated during blood gas analysis. That is the headline finding of a recently published study that is, according to the authors, the first ever to investigate the effect of hemolysis on blood gas analytes. Venous blood was sampled from nine...

Point of care (POC) testing has become an important part of nephrological care. In cases of acute renal failure, POC is indispensable in deciding the need for dialysis, but is also essential in the management of patients on regular dialysis. For example, hyperhydration, cardiovascular adverse events and inflammation...

Few studies have addressed the predictive value of C-reactive protein at different cutoff values in appendicitis. We have determined the cutoff values for C-reactive protein levels at different periods during clinical evolution of appendicitis and established their use to support the diagnosis of appendicitis. The...

Arterial blood gases (ABG), a clinical test that involves measurement of the pH of arterial blood and the amount of oxygen and carbon dioxide dissolved in arterial blood, is routinely used in the diagnosis and monitoring of predominantly critically/acutely ill patients being cared for in hospital emergency rooms and...

Extracellular (serum) potassium concentration is normally maintained within the approximate reference range of 3.5-5.2 mmol/L; this is important for normal cardiac function. Both reduced serum potassium (hypokalemia) and increased serum potassium (hyperkalemia) can, if sufficiently severe, be associated with...

Arterial blood gas analysis in cases of metabolic acidosis reveals primary decrease in pH and bicarbonate, and secondary (compensatory) reduction in pCO₂. The most common cause of metabolic acidosis is increased production of endogenous metabolic acids, either lactic acid, in which case the condition is called lactic...

The incorporation of CO-oximeters in modern blood gas analyzers allows rapid determination of the amount of carboxyhemoglobin in blood. This, in turn, allows rapid diagnosis of carbon monoxide poisoning, the subject of a recently published review.  This wide-ranging review article begins with consideration of the...

The calcium present in blood plasma comprises two almost equal fractions: half is bound to albumin and the remainder is unbound, free ionized calcium. Only the free ionized calcium is physiologically active. There are two ways of assessing patient blood calcium status.  The first – at one time the only available...

Pulse oximeters, which are ubiquitous in nearly all areas of clinical care, provide the means for safe, non-invasive continuous monitoring of blood oxygen saturation. The validity of using pulse oximetry to assess patient blood oxygenation status depends on SpO₂, the parameter measured by pulse oximetry, being a...

Diagnosing heart failure (HF) in patients presenting in primary care is difficult. Clinical assessment of symptoms and signs has limited sensitivity and specificity. NT-proBNP determination has been proven to be useful and accurate for ruling out the diagnosis of systolic HF, and some have even proposed different...