One of the principal clinical uses of blood gas analysis is assessment of patient acid-base status, but over the years controversy has dogged understanding of the principles of acid-base physiology and interpretation of blood gas results.  In a brief review of the history of clinical acid-base balance, the author...

Raised serum bilirubin (hyperbilirubinemia) and consequent jaundice is common during the neonatal period; around half of all newborns become temporarily jaundiced during the first week or two of life. For the vast majority, serum bilirubin peaks no higher than around 250 µmol/L (14.6mg/dL) and jaundice quickly...

Hospital mortality rates provide information for evaluating the relative quality of the health care delivered. However, interpretation of hospital mortality rates is fraught with difficulty, not least because such bald data does not take account of the severity of the illness of patients, whose outcome is being...

The maintenance of normal blood pH depends crucially on synergy of action between lungs and kidneys, so that students of acid-base physiology must become familiar with the interrelatedness of kidney and lung function in both health and disease.  This interrelatedness is the central theme of a recently published review ...

A recently published paper describes the sad case history of a 17-year-old man who was brought, unconscious and totally unresponsive (Glasgow Coma Score 3), by ambulance to the emergency department of his local hospital. Blood gas analysis revealed he was suffering severe metabolic acidosis (pH 7.25, bicarbonate 9...

This is the second in a series of articles. The first essay, “Quality control in theory and practice – a gap analysis”, published here in January 2006 raised the question: Has “the system” given front-line laboratory workers the knowledge and tools they need to make quality control decisions wisely – or is there a...

Until 1978, the year of the first oxygenless ascent of Mount Everest, it had been assumed that it was impossible to survive at the summit of Mount Everest (altitude 8800 m) without supplemental oxygen. At this high altitude, pO2 of inspired air is around 50 mmHg, a third of the oxygen content of air at sea level....

Reduced plasma sodium concentration (hyponatremia) is the most common electrolyte disturbance, affecting up to 15 % of hospitalized patients. There are many possible causes and the identification of cause is often important for the management of the severely hyponatremic patient. There is some evidence to suggest that ...

Measurement of blood lactate provides clinicians with a valuable means of identifying and monitoring critically ill patients who are suffering clinical shock as a result of severe trauma, sepsis or cardiogenic shock. Lactic acid accumulates in the blood of these patients due to the tissue hypoxia that results from...

"Diabetes of injury" is a term that has been used to describe the insulin resistance and resulting hyperglycemia that is a frequent feature of severe trauma and critical illness. It was once supposed that hyperglycemia is a consequence of critical illness; an adaptive, protective stress response, which is important...