The biphasic transmittance waveform: an early marker of sepsis in patients with neutropenia

Transmittance waveform (TW) analysis has been proposed as a method of both prediction and monitoring of non-overt and overt disseminated intravascular coagulation. This study assessed the use of the rapidTW of the activated partial thromboplastin time in the detection of sepsis in 49 consecutive neutropenic haemato-oncology patients. A slope 1 cut-off value of -0.050 was found to be optimum giving 85% sensitivity with 92% specificity and positive and negative predictive values of 62% and 98%, respectively. Furthermore a worsening slope 1 value at 24 hours was indicative of a 60% increase in mortality risk. Haemato-oncology patients have a significantly increased risk of developing sepsis during intensive chemotherapy, exacerbated by the resultant neutopenia. This sepsis may progress extremely rapidly and is associated with a high mortality. Early diagnosis is therefore critical and is currently made on a predominantly clinical basis with supporting microbiological evidence 2-3 days later. This study showed that TW offers an early marker, predictive of sepsis in neutropenic patients. It correlates with subsequent microbiological results and may identify patients at greater risk of clinical deterioration who may require more intensive early therapy or observation. It may also provide a useful marker to monitor the effects of treatment.