Novel and diagnostically applicable information from optical waveform analysis of blood coagulation in disseminated intravascular coagulation

Abstract

Summary.Transmittance waveform is the term applied to the optical profile generated from the process of clot formation on standard coagulation tests run on the MDA-180, a new-generation automated coagulation analyser. In patients with disseminated intravascular coagulation, a characteristically abnormal 'biphasic change' is seen on both the activated partial thromboplastin time and thrombin time waveforms. Increasing steepness of the initial slope on the waveform correlates with clinical deterioration and fulminant progression. Although the mechanism underlying the biphasic appearance remains to be elucidated, its identification provides the diagnostic laboratory with a simple, rapid and robust assay for disseminated intravascular coagulation that can help the clinician with urgent and appropriate therapeutic interventions.

Biphasic transmittance waveform in the APTT coagulation assay is due to the formation of a Ca++-dependent complex of C-reactive protein with very-low–density lipoprotein and is a novel marker of impending disseminated intravascular coagulation

“…Initial reports of Downey et al, 3,4 which indicated an association between the BPW and DIC in intensive care patients, suggest a CRP levels were measured in the VLDL fraction isolated from serum. Measurements were also determined on samples from sera supplemented with either EDTA or Ca 2ϩ .…”

“…1,2 The biphasic waveform (BPW) was initially described when a decrease in plasma light transmittance before clot formation on the MDA 180 automated coagulation analyzer was shown to correlate with disseminated intravascular coagulation (DIC) in critically ill patients. [3][4][5] In contrast to the normal sigmoidal waveform pattern that is characterized by an initial 100% light transmittance phase before clot formation, patients with a biphasic pattern had an immediate, progressive decrease in light transmittance that occurred even in the preclotting phase. The magnitude of this BPW often varied with sequential samples taken from individual patients and appeared early in samples from patients who were later diagnosed with DIC by more conventional criteria.…”

Early identification of sepsis and mortality risks through simple, rapid clot-waveform analysis

“…The formation of this lipoprotein-complexed CRP (LCCRP) is the molecular mechanism underlying the atypical biphasic transmittance waveform observed in simple tests of coagulation, such as the activated partial thromboplastin time (aPTT) [2]. The extent of LCCRP formation correlates with the degree of waveform change that occurs when a patient's plasma is re-calcified on the MDA 180 photo-optical analyser.…”

Tests of global haemostasis and their applications in bleeding disorders

“…Effectiveness of Factor VIII infusions in haemophilia A patients with high responding inhibitors reflected changes in APTT WA seen even 24 h after FVIII infusion and even when FVIII:C was less than 1.0 IU/dL [35]. It has also been used to monitor the use of bypassing agents such as APCC or rFVIIa in patients with haemophilia and inhibitors [36]. There are not many reports on the use of APTT WA in patients with other bleeding disorders, but its potential use in monitoring patients with disseminated intravascular coagulation (DIC) and sepsis [37] and in evaluating lupus anticoagulants [38] has been described.…”