E. W. Etchill1, M. C. Vespe2, A. Hassoune4, J. L. Correa Lopez3, M. R. Rosengart1, A. B. Peitzman1, M. D. Neal1 1University Of Pittsburgh School Of Medicine,Surgery,Pittsburgh, PA, USA 2Carnegie Mellon University,Statistics,Pittsburgh, PA, USA 3Universidad de Caldas,Surgery,Manizales, Caldas, Colombia 4American University Of Beirut,Surgery,Beirut, Beirut, Lebanon
Introduction: Massive transfusion is currently defined as the transfusion of at least 10 red blood cell (RBC) units in 24 hours. Unlike in trauma, the transfusion patterns for massively transfused nontrauma patients have not been explored. However, most institutions have recently implemented identical transfusion protocols for both trauma and nontrauma patients. We hypothesized that distinct subpopulations of massively hemorrhaging patients exist based on patterns of product transfusion.
Methods: We used cluster-based modeling to characterize transfusion patterns in massively transfused trauma and nontrauma patients. Massively transfused nontrauma patients from a single institution were identified and classified into the following groups: cardiovascular (CV), gastroenterology (GI), transplant, and spine surgery. We identified distinct trajectories for product delivery and compared the distribution of patients in each trajectory by transfusion indication.
Results: 363 patients were included for analysis, including 298 nontrauma patients. The median age was 54 years. GI surgery patients accounted for 34% of nontrauma patients, while CV patients comprised 23%. Transplants accounted for 32% and spine procedures 7%. Thirty day mortality among all patients who completed a 24 hour transfusion period was 27%. All patients received an average of 17 cumulative units of blood cells, 14 units plasma, and 14 units of platelets.
Three distinct trajectories were extracted (Figure 1). Most trauma (85%) and cardiovascular surgery (63%) patients fit into trajectory 1, while most GI (57%) and transplant patients (63%) comprise trajectory 3. Trajectory 2 primarily consists of a subset of GI (29%) and transplant (31%) patients. The difference in distribution of patients in each trajectory is statistically significant (p < 0.004). Three plasma and four platelet transfusion ratio trajectories were also extracted and exhibit similar variability.
Conclusion: We identified three patterns of product transfusion among all massively transfused patients. Trauma and cardiovascular patients are more likely to receive the majority of their blood products early, while GI and transplant patients receive products over a longer period of time. There is also a subset of GI and transplant patients that may not be adequately resuscitated during the initial attempts, ultimately leading to greater transfusion requirements. Future investigation into the impact of additional clinical characteristics on transfusion trajectories, as well as the effect of trajectories on patient outcomes, will allow us to more appropriately investigate and resuscitate this heterogeneous massive transfusion population.
