Preanalytical errors are quite frequent in the area of point-of-care testing (POCT). There are many reasons for that. First of all, POCT testing is usually performed by clinical staff (i.e. nurses and physicians), who are neither so skilled nor educated for laboratory work as laboratory professionals. Moreover,...

Despite the pervasive measurement of cardiac troponin (cTn) for the diagnosis of myocardial infarction (AMI) and acute coronary syndromes (ACS), the continuous evolution of assays and guidelines for their application has created uncertainty among laboratorians and clinicians: criteria for the choice of assay and...

The anion gap (AG) is a calculated parameter derived from measured plasma electrolyte concentrations that is most frequently used to elucidate acid-base disturbances in the critically ill. It is defined as the difference between measured anions and cations in blood plasma and is calculated by subtracting the sum of...

Around 25 % of blood samples recovered from patients admitted to intensive care and 8 % of those recovered from all other hospitalised patients would return a plasma sodium result 4-10 mmol higher than its true value if the method of analysis was indirect ion selective electrode (ISE). This is the headline finding of...

Arterial blood gases are frequently useful in the clinical management of patients with chronic obstructive pulmonary disease (COPD) to assess both oxygenation and acid-base status.   A recent review article focuses on disturbance of acid-base in these patients, which occurs in advanced disease when pulmonary gas...

According to the authors of a recently published study little is known of the clinical effects of abnormal plasma chloride concentration among the critically ill. Their retrospective study illuminates this apparent grey area of clinical knowledge.  The study involved retrieval and analysis of laboratory data,...

Frequent blood glucose measurement is one element of the routine intensive monitoring that all critically ill patients receive following admission to intensive care units. Transient increase in blood glucose concentration (hyperglycemia) is very common in this patient group.  The significance of this so called stress...

Unless suffering some unrelated acute/critical illness, diabetic patients are only usually submitted for arterial blood gas analysis if they are suspected of suffering diabetic ketoacidosis, the potentially life-threatening acute complication of diabetes that is almost invariably associated with severe hyperglycemia....

Clinical laboratories usually have a policy for repeat testing when the test result is either grossly abnormal or unexpected in terms of recent validated test results for that particular patient. The rationale for this policy is that the first test result may represent a clinically significant analytical error, which...

By measurement of the partial pressure of oxygen in arterial blood (pO₂(a)) and oxygen saturation in arterial blood (sO₂(a)), blood gas analysis provides the means for monitoring supplemental oxygen therapy. Oxygen is prescribed in many medical emergencies in which tissue oxygenation is threatened because of...