In Response We appreciate the comments by Pivalizza and De Haan.1 As alluded to in their letter,1 anesthesiologists indeed were responsible for the majority of plasma transfusion orders at our institution during the study period. These occurred both intraoperatively (45%) and postoperatively (37%) in the intensive care unit, where the majority of our surgical intensive care units are staffed by anesthesiologists who have completed fellowship training in critical care.2 Regarding viscoelastic testing, our institution utilizes thromboelastography (TEG) but not universally for coagulation management decisions. Primarily, TEG is used in trauma, cardiac surgery, and solid-organ transplantation. Of those receiving plasma intraoperatively with a valid pretransfusion and posttransfusion international normalized ratio (INR), approximately 25% (795 patients) also had TEG data available both pretransfusion, defined as occurring within 1 hour of the first unit of plasma administered, and posttransfusion, defined as occurring within 6 hours after administration of the last unit of intraoperative plasma. We have recently published our experience with changes in TEG-derived R-time values after plasma transfusion and clinical outcomes for these patients.3 Concerning situations when the INR is not available, Supplemental Figure 1 shows that 3244 patients (29.7% of all adult patients receiving plasma over the study period of interest) were excluded for absence of either a pretransfusion or posttransfusion INR. Moreover, a total of 899 patients met criteria for massive transfusion over the study period as defined by ≥10 units of red blood cells administered within a single 24-hour period. This would represent approximately 8% of all patients who received plasma over the study period of interest, of which only a minority (approximately 5%) was directly related to trauma rather than other types of surgical insults. Of note, 643 (71.5%) were included in the current investigation, implying that they had qualifying pretransfusion and posttransfusion INR values available despite their large transfusion requirements. In light of the ongoing uncertainty regarding optimal plasma transfusion practices in nontrauma-related massive hemorrhage, additional investigations examining plasma transfusion practices in this broad cohort of massively transfused patients would certainly assist in advancing our understanding of clinical blood management decisions. Of particular interest, there is increasing evidence that optimal resuscitation strategies for patients with nontraumatic massive hemorrhage may differ from the trauma population. Specifically, delivery of high ratios of plasma to red blood cells, such as those given in protocol-driven fixed ratios, may not be associated with improved outcomes in this group.4,5 However, data are limited, and as such, optimal transfusion strategies for nontraumatic massive hemorrhage should be considered an area of research priority. Matthew A. Warner, MDDaryl J. Kor, MDDivision of Critical Care MedicineDepartment of Anesthesiology and Perioperative MedicineMayo ClinicRochester, MinnesotaDepartment of Anesthesiology and Perioperative MedicinePeriprocedural Outcomes, INformation and Transfusion Study GroupMayo ClinicRochester, Minnesota[email protected]