Staying on Target: Maintaining a Balanced Resuscitation During Damage Control Resuscitation Improves Survival.

Background Damage control resuscitation (DCR) improves survival in severely bleeding patients. However, deviating from balanced transfusion ratios during a resuscitation may limit this benefit. We hypothesize that maintaining a balanced resuscitation during DCR is independently associated with improved survival. Methods This was a secondary analysis of the PRospective Observational Multicenter Major Trauma Transfusion (PROMMTT) study. Patients receiving ≥3 units packed red blood cells (PRBC) in one-hour over the first 6-hours and surviving beyond 30-minutes were included. Linear regression assessed the effect of percent time in a high-ratio range on 24-hour survival. We identified an optimal ratio and percent of time above the target ratio threshold by Youden's index. We compared patients with a 6-hour ratio above the target and above the percent time threshold (On-Target) with all others (Off-Target). Kaplan-Meier analysis assessed the combined effect of blood product ratio and percent time over the target ratio on 24-hour and 30-day survival. Multivariable logistic regression identified factors independently associated with 24-hour and 30-day survival. Results Of 1,245 PROMMTT patients, 524 met inclusion criteria. Optimal targets were plasma:PRBC and platelet:PRBC of 0.75 and ≥40% time spent over this threshold. For plasma:PRBC, On-Target (n=213) vs Off-Target (n=311) patients were younger (median 31-years, interquartile range [22, 50] vs 40 [25, 54], p=0.002) with similar injury burdens and presenting physiology. Similar patterns were observed for platelet:PRBC On-Target (n=116) and Off-Target (n=408) patients. After adjusting for differences, On-Target plasma:PRBC patients had significantly improved 24-hour (OR 2.25, 95% CI, 1.20-4.23) and 30-day (OR 1.97, 95% CI 1.14-3.41) survival while On-Target platelet:PRBC patients did not. Conclusion Maintaining a high ratio of plasma:PRBC during damage control resuscitation is independently associated with improved survival. Performance improvement efforts and prospective studies should capture time spent in a high-ratio range. Level of evidence Epidemiologic/prognostic study, Level II.