Traditionally, interpretation of blood gas results for the assessment of acid-base status has been based on the Henderson-Hasselbalch equation, the central focus of which is the carbon dioxide – the bicarbonate buffer system. At its most reduced form the equation can be stated as “pH is proportional to the ratio of...

Neonatal jaundice is the subject of two recent studies and an accompanying editorial, all published in the October issue of Archives of Disease in Childhood (Neonatal Edition). The aim of the first study was to determine if visual assessment of jaundice on day 2-3 of life is accurate in estimating serum bilirubin and...

Troponin values above the 99th percentile and increasing/falling values found by serial testing in addition to signs and symptoms of myocardial ischemia means AMI. Low troponin values, near or below the 99th percentile, can be used for prognosis. Highest hazard ratios were found when using the 90th percentile,...

Pleural effusion, defined as excess fluid in the pleural space, can complicate the course of a large and pathologically diverse range of pulmonary and non-pulmonary diseases. Laboratory analysis of pleural fluid provides much useful information for the clinician whose diagnostic challenge is the patient presenting...

Sepsis and septic shock lead to local and systemic activation of different response systems, including coagulation and fibrinolysis.  Despite numerous attempts the high mortality rate of these patients has remained stable over the last 20 years. In this overview the pathophysiological insights and possible...

Sensitivity and specificity define the discriminative power of a diagnostic procedure, whereas predictive values relate to the predictive ability of a test to identify disease or its absence in individuals.  Predictive values are greatly influenced by the prevalence of the disease and should not be generalized beyond ...

The anion gap (AG) is a calculated parameter derived from measured serum/plasma electrolyte concentrations. The clinical value of this calculated parameter is the main focus of this article. Both increased and reduced anion gap have clinical significance, but the deviation from normal that has most clinical...

Close to 20 % of those suffering significant trauma develop thrombocytosis (raised platelet count) in the days and weeks following injury. Although this thrombocytosis is associated with increased risk of complications during recovery, it is also associated with decreased risk of death and thus may have overall...

Although transfusion of donated blood can be life saving, it is a procedure associated with considerable potential risk to the recipient patient. As with any medical treatment or procedure the decision to prescribe donated blood must be made after assessment of the balance between benefit and risk for that particular...

The incidence and significance of hypernatremia (raised plasma sodium) acquired during critical illness is the subject of a recently published retrospective study conducted at the combined medical and surgical intensive care unit of a Brisbane hospital where plasma sodium of all patients is regularly monitored...