Two very different reviews of acid-base pathophysiology are recently published. The first, written by a nurse educator is a comprehensive overview and serves as an introduction to the topic. The approach is familiar and reflects standard physiology texts.  After a very brief synthesis of the significance of...

In health the partial pressure of oxygen (pO₂) in arterial blood is maintained between 10.6 and 13.3 kPa (80-100 mmHg). Hypoxemia (reduced arterial pO₂) is usually a signal of significant respiratory or cardiac disease and respiratory failure is defined as arterial blood pO₂ < 8 kPa ( So when arterial blood gas...

In the USA it is permissible to store donated blood for transfusion for up to 42 days. Although this is helpful in matching supply with demand for blood products, red cells undergo a number of changes in storage that affect their function.  There is conflicting evidence to suggest that the structural and functional...

Respiratory acidosis and alkalosis are characterized by primary change in pCO₂ (increase in the case of acidosis and decrease in the case of alkalosis). Secondary physiological compensation, aimed at returning blood pH to normal, is evident in blood gas results as a change in bicarbonate concentration (increase in the ...

Transient increase in serum bilirubin concentration is a normal physiological feature of the neonatal period and this rise is sufficient to cause visible jaundice in around 60 % of newborns. For most the condition is harmless and resolves spontaneously with no long-term effects. However for those neonates with...

Maintaining lasting progress in laboratory test utilization is difficult to do without a reminder tool for providers. Since implementation of a quarterly physician report card in 2003, we have seen sustained improvement in the ordering of wellness tests in an ambulatory care network in the United States for over four...

Reduced plasma sodium concentration (hyponatremia), the most common electrolyte abnormality in hospitalized patients, is the subject of a recently published review. Disordered secretion of the pituitary hormone vasopressin (alternative name, antidiuretic hormone ADH) is central to the pathogenesis of hyponatremia for...

Critically ill patients often require frequent monitoring of blood gases and the arterial blood required for these analyses is most conveniently sampled via an indwelling arterial catheter; arterial catheterization also provides the means for continuous monitoring of blood pressure.  Of all the invasive procedures...

Umbilical cord blood gas analysis has for many years been recommended for assessment of newborn babies after high-risk delivery associated with possible hypoxic stress and consequent risk of permanent brain damage. More recently there has been an increasing trend towards its routine use after all deliveries.  With...

Reduction in platelet numbers (thrombocytopenia) is associated with reduced hemostatic response to blood-vessel injury and therefore increased risk of bleeding. In health, the concentration of platelets in peripheral blood is maintained within the range of 150-400 × 10³/mL. The risk of spontaneous life-threatening...