Highlights from EAST - Acute lung injury after massive transfusion

One presentation this morning from Memphis shows us that the increased plasma in MTP does not cause pulmonary dysfunction.

DOES PLASMA TRANSFUSION PORTEND PULMONARY DYSFUNCTION? A TALE OF TWO RATIOS

Authors
John P. Sharpe , MD , Jordan A. Weinberg , MD , Louis J. Magnotti , MD , Timothy C. Fabian , MD , Martin A. Croce , MD , University of Tennessee Health Science Center

Objective
An unresolved concern regarding resuscitation in the setting of massive hemorrhage is potential lung injury from the transfusion of relatively more plasma-rich components. However, the association between plasma to RBC ratio and subsequent pulmonary dysfunction remains unclear. The purpose of this study was to evaluate the impact of plasma:RBC on P/F ratio in the setting of massive transfusion (MT).

Methods
Over a 5.5 year period, prospective data were collected on trauma patients who underwent MT, defined as =10 unit RBC transfusion by completion of hemorrhage control. Deaths within 48h of arrival were excluded. Acute lung injury (ALI) and ARDS were defined as P/F ratio <300 and <200 at 48h respectively. Stepwise multiple regression analysis was performed to determine variables significantly associated with P/F ratio.

Results
199 patients met inclusion criteria. 159 (80%) developed ALI and 105 (53%) developed ARDS. ALI and ARDS were both associated with subsequent mortality: ARDS (24%) vs. no ARDS (2.5%), p <0.05; ALI (21%) vs. no ALI (2.5%), p <0.05. Paradoxically, patients with P/F ratio =300 were found to have received more plasma (5.6 vs. 4.3 units, p <0.05) and higher plasma to RBC ratio (1:2 vs. 1:3, p <0.05) at completion of hemorrhage control. Stepwise multiple regression analysis, however, identified age (p <0.001) and chest AIS (p = 0.04), but not plasma:RBC (p = 0.10) to be independent determinants of P/F ratio at 48 hours.

Conclusion
In this cohort of MT patients who survived beyond the first 48 hours, pulmonary dysfunction developed in the majority, and was associated with a 10-fold higher risk of subsequent death. However, plasma to RBC ratio achieved during hemorrhage control had neither a positive nor negative impact on subsequent P/F ratio. Liberal transfusion of plasma-rich components in the MT setting may not, in fact, be deleterious to lung function.