CO-oximetry provides the means for automated spectrophotometric measurement of the concentration of total hemoglobin (ctHb) in blood and the percentages of the four hemoglobin derivatives that total hemoglobin comprises: oxyhemoglobin (O₂Hb); deoxyhemoglobin (HHb); carboxyhemoglobin (COHb); and methemoglobin (MetHb)....

Neonates nearly always experience their single largest day of blood loss on the day of birth due to admission laboratory testing. The term "admission laboratory testing" refers to the initial blood tests done when a baby is born and admitted to the NICU.  Total circulating blood volume in a 3.5 kg term newborn is 280...

Ensuring adequate oxygen delivery to tissues is a prime objective of acute/critical medical care. There is no routinely available method for directly monitoring tissue oxygenation; instead clinicians must depend on available indirect measures. Although not the only factor to be considered, measurement of the amount of ...

Reprinted from Ann Lab Med 2013 Sep; 33(5):309-18. Christenson E, Christenson RH: "The role of cardiac biomarkers in the diagnosis and management of patients presenting with suspected acute coronary syndrome". Myocardial infarction (MI) is the leading cause of death in the developed world. Biomarkers have an...

With increasing age, an unspecific rise of fibrin degradation product in blood is observed. Thus, the D-dimer test to rule out thromboembolic events has a high false positive rate in elderly patients. In 2010, Douma et al introduced a formula to adjust D-dimer cut-off values for age in outpatients >50 years: Age ×...

How do errors occur in the laboratory and what can we do to prevent errors? Any test can and will fail if incorrectly performed or operated under the wrong conditions. The role of the laboratory director is to determine those conditions and to understand test limitations in order to prevent laboratory errors....

Recently developed high-sensitivity cardiac troponin (cTn) assays can measure approximately 10 times lower concentrations with high precision (coefficient of variation, <10 % at the 99th percentile of the upper reference limit) than conventional assays, and can measure cTn concentrations in at least 50 % of a reference ...

Point of care (POC) testing has become an important part of nephrological care. In cases of acute renal failure, POC is indispensible in deciding the need for dialysis, but is also essential in the management of patients on regular dialysis. For example, hyperhydration, cardiovascular adverse events and inflammation...

Arterial blood gases (ABG), a clinical test that involves measurement of the pH of arterial blood and the amount of oxygen and carbon dioxide dissolved in arterial blood, is routinely used in the diagnosis and monitoring of predominantly critically/acutely ill patients being cared for in hospital emergency rooms and...

Calcium is an essential mineral required for numerous biological functions. In circulation, calcium is found in three different fractions, anion-bound, protein-bound and free or ”ionized”. The amount of calcium in each of these fractions is dependent on the concentration of hydrogen ions, anions and plasma proteins....