Although creatinine clearance has been the mainstay for estimating glomerular filtration rate (GFR) in laboratories for the past half-century, prediction equations based on serum creatinine and other routine serum analytes are now available which enable reporting of a calculated GFR using the Modification of Diet in...

Reprinted with permission from British Journal of Nursing, 2004, Vol 13, No 9.  Arterial puncture is the most common method used to obtain a sample for the measurement of arterial blood gases (ABGs) and is essential to guide the prescription of long-term oxygen therapy (LTOT) in patients with chronic hypoxic lung...

This is the third in a series of four essays on www.acutecaretesting.org.  The first essay, "Quality control in theory and practice – a gap analysis", 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...

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...

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...

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 ...

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....

"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...

Carboxyhemoglobin (COHb) is the product of the reaction between hemoglobin and carbon monoxide, and measurement of COHb is used in the diagnosis of carbon monoxide poisoning. Since carbon monoxide is a common pollutant present in cigarette smoke and car exhaust, it is difficult to be too dogmatic about what...

The National Kidney Disease Education Program (NKDEP) Laboratory Working Group reviewed problems related to serum creatinine measurement for estimating glomerular filtration rate (GFR) and prepared recommendations to standardize and improve creatinine measurement. The NKDEP recommends using the estimating equation...