PB1067 - Pre-DIC APTT curves in critical surgical patients: useful or just pretty pictures?

Background: Activated partial thromboplastin time (APTT) testing can sporadically reveal a distinctive biphasic clot waveform associated with disseminated intravascular coagulation (DIC), as documented in scientific literature (Toh et al.). This irregularity correlates with hemostatic disruption severity. Referred to as pre-DIC curves, they result from precipitate formation involving very-low-density lipoprotein (VLDL) and C-reactive protein (CRP). Despite this knowledge, clinical experience remains limited.

Aims: The objective of this study was to assess the potential correlation between the identification of pre-DIC APTT curves and the clinical manifestation of DIC in surgical intensive care unit (ICU) patients.

Methods: APTT tests were conducted as routine diagnostic procedures for intensive care unit (ICU) patients during the period spanning August to November 2023, employing the Sysmex CS-5100 hemostasis analyzer. A skilled biochemist analyzed qualitative clot waveform deviations. Instances resembling pre-DIC curves were archived and later compared with patient profiles, including medical histories, additional laboratory findings, and clinical courses.

Results: During the analyzed period, 18 patients with pre-DIC curves were identified. All had severe sepsis, indicated by elevated CRP and procalcitonin, as well as need for vasopressors to achieve hemodynamic stability. Only 8 had significant bleeding, and 3 developed overt DIC. Among the DIC cases, one had a severely pathological curve, while the other two were mild. Patients with the most pronounced biphasic morphology had extremely high inflammation markers. Nine patients died during hospitalization, while others improved clinically.

Conclusion(s): Despite the occurrence of pre-DIC curves in surgical patients experiencing septic shock, their presence did not consistently correlate with a severe clinical trajectory characterized by complications such as hemorrhage, thrombosis, or disseminated intravascular coagulation (DIC). Contrary to the previous reports, extent of waveform irregularity did not correlate with development of DIC.