Metabolic alkalosis is a disturbance of acid-base balance, with many possible causes, characterized by primary increase in blood bicarbonate (HCO₃) and pH. Hypoventilation is the normal compensatory respiratory response to metabolic alkalosis. This results in increased pCO₂ and, if the metabolic alkalosis is...

In health plasma potassium concentration is maintained between 3.5 and 5.2 mmol/L. The most significant clinical effect of both raised plasma potassium (hyperkalemia) and reduced plasma potassium (hypokalemia) is on the myocardium (heart muscle).  This reflects the fact that the resting membrane potential of cardiac...

Many hospitals have a pneumatic tube system (PTS) that is routinely used to transport blood samples rapidly to the central laboratory, but the notion that such systems can be used to transport samples destined for blood gas analysis is challenged by the results of a recent study.  This prospective study, focusing on...

Increased serum bilirubin, clinically manifest as jaundice, is very common during the first week of life, affecting around 60 % of full-term babies and 85 % of babies born prematurely. For the vast majority this neonatal jaundice is a mild transitory phenomenon with no long-term consequences. The greatest fear...

Blood gas analysis (BGA) provides the means for the most accurate assessment of patient oxygenation status; the two relevant blood gas parameters being partial pressure of oxygen in arterial blood (pO₂(a)), and % hemoglobin oxygen saturation (sO₂(a)).  Pulse oximetry, a technology now ubiquitous in all areas of...

Anemia, which is defined as hemoglobin (Hb) concentration The kidneys are essential to the regulation of red-cell production and thereby maintenance of normal Hb concentration because the hormone erythropoietin, which regulates red-cell production, is synthesized in the kidneys. The usually normochromic, normocytic...

Anemia and consequent need for red-cell transfusion is a common feature of critical illness. According to a recently published review of the topic, nearly all (95 %) patients who have been in an intensive care unit for longer than 3 days become anemic.  For close to 50 % of these patients, anemia is considered of...

Metformin is an oral hypoglycemic drug that has long been employed in the treatment of type 2 diabetes; it is particularly widely prescribed for those diabetics who are obese. Very rarely, metformin use results in severe lactic acidosis, most often occurring in patients with reduced renal function.  Although a very...

In health, serum potassium concentration is maintained within the approximate range of 3.5-5.2 mmol/L. Disturbance of potassium homeostasis is a common electrolyte disorder that is clinically manifest through its adverse effect on both skeletal and cardiac muscle cell function.  Although often asymptomatic, both...

Acetaminophen (alternative name paracetamol) is one of the most frequently used drugs and widely considered very safe in almost all clinical contexts so long as the maximum recommended dose is not exceeded.  When taken in overdose, however, it can cause acute liver failure (ALF). In fact, acetaminophen...