Comparing hemostatic resuscitation management of intraoperative massive bleeding with traumatic massive bleeding: a computer simulation

Abstract

Background: Appropriate blood component transfusion might differ between intraoperative massive bleeding and traumatic massive bleeding in the emergency department because trauma patients initially bleed undiluted blood and replacement typically lags behind blood loss. We compared these two blood loss scenarios, intraoperative and traumatic, using a computer simulation.

Methods: We modified the multi-compartment dynamic model developed by Hirshberg and implemented it using STELLA 9.0. In this model, blood pressure changes as blood volume fluctuates as bleeding rate and transcapillary refill rate are controlled by blood pressure. Using this simulation, we compared the intraoperative bleeding scenario with the traumatic bleeding scenario. In both scenarios, patients started to bleed at a rate of 50 ml/min. In the intraoperative bleeding scenario, fluid was administered to maintain isovolemic status; however, in the traumatic bleeding scenario, no fluid was supplied for up to 30 min and no blood was supplied for up to 50 min. Each unit of packed red blood cells (PRBC) was given when the hematocrit decreased to 27%, fresh frozen plasma (FFP) was transfused when plasma was diluted to 30%, and platelet concentrate (PC) was transfused when platelet count became 50,000/ml.

Results: In both scenarios, the appropriate ratio of PRBC:FFP was 1:0.47 before PC transfusion, and the ratio of PRBC:FFP:platelets was 1:0.35:0.39 after initiation of PC transfusion.

Conclusion: The ratio of transfused blood component did not differ between the intraoperative bleeding and traumatic bleeding scenarios.

Keywords: Blood coagulation disorder; Blood component transfusion; Computer simulation; Hemorrhage.

Fig. 1.

Overview of the model. Arrows represent the mathematical relationships between compartments. PRBC: packed red blood cells, FFP: fresh frozen plasma, PC: platelet concentrate.

Fig. 2.

Model prediction of hematocrit (%), plasma dilution (%), bleeding fraction and adjusted platelet count (/ml) in the intraoperative bleeding scenario. Phase 1: bleeding started, but only crystalloid fluid was given to maintain normal blood pressure. Phase 2: PRBC administration was started at 43 min and the bleeding fraction was 0.44. PRBCs were administered. Phase 3: FFP was started at 164 min and the bleeding fraction was1.67. PRBCs and FFP were given. Phase 4: PC was started at 219 min and the bleeding fraction was 2.24. PRBCs, FFP, and PC were given. Bleeding fraction: cumulative blood loss / initial blood volume. PRBC: packed red blood cells, FFP: fresh frozen plasma, PC: platelet concentrate.

Fig. 3.

Model prediction of hematocrit (%), plasma dilution (%), bleeding fraction, adjusted platelet count (/ml) and systolic blood pressure (mmHg) in the traumatic bleeding scenario. Phase 1: bleeding started and no fluid was administered until 30 min when the patient arrived at the ER. At that time, blood pressure was 84 mmHg, bleeding volume was 1,175 ml, and transcapillary refill was 449 ml. Administration of crystalloid fluid started. Phase 2: PRBC administration was started at 52 min and the bleeding fraction was 0.42. Only PRBCs were given. Phase 3: FFP administration was started at 170 min and the bleeding fraction was 1.63. PRBCs and FFP were given. Phase 4: PC administration was started at 225 min and the bleeding fraction was 2.20. PRBCs, FFP, and PC were given. Bleeding fraction: cumulative blood loss / initial blood volume. ER: emergency room, PRBC: packed red blood cells, FFP: fresh frozen plasma, PC: platelet concentrate.