BACKGROUND: Recent data for adult trauma patients suggest improved survival when using hemostatic resuscitation, which includes limiting crystalloids and using closer to 1:1 ratios for both fresh frozen plasma (FFP) and platelets (PLTs) relative to packed red blood cells (PRBCs). Pediatric studies have shown similar but mixed results and often lack measuring crystalloids. We seek to evaluate in-hospital survival based on crystalloid administration and different blood product ratios in pediatric casualties during the recent conflicts. METHODS: We queried the Department of Defense Trauma Registry for all pediatric encounters in Iraq and Afghanistan from January 2007 to January 2016 and included those with at least 40 mL/kg of total blood products administered provided that they received at least 1 U of PRBC. We grouped children as younger (0–7 years) and older (8–17 years). We grouped low versus high ratios for FFP/PRBC (≤1:2 vs. >1:2) and PLT/PRBC (≤1:6 vs. >1.6). We used a threshold of 40 mL/kg to for high versus low crystalloid resuscitation. RESULTS: During this time, there were 3,439 encounters in the registry with 521 (15.1%) that met the inclusion criteria. The median age of casualties that met the inclusion was 10 years (interquartile range, 5–13), most were male (73.5%), with a moderate median injury severity score (17; interquartile range, 13–25). We performed regression modeling with adjustments for mechanism of injury, composite injury severity score, and total blood product volume (mL/kg based), grouping children based on high versus low fluid resuscitation. In the low-volume crystalloid group, we found that higher (>1:2) FFP/PRBC was associated with improved survival (odds ratio [OR], 3.42). However, in the high fluid crystalloid resuscitation group, we found that that higher ratios for PLT/ PRBC (>1:6) overall (OR, 0.46) and the FFP/PRBC (>1:2) in younger children (OR, 0.28) was associated with worse survival. The remaining associations were not statistically significant. CONCLUSION: We found an association with survival in massively transfused pediatric trauma patients who received both a high FFP/PRBC ratio and low crystalloid administration. The benefit of this high ratio is negated, in patients receiving high crystalloid volumes, particularly among smaller children. Future studies on hemostatic resuscitation evaluating blood product ratios should also account for crystalloid and colloid administration.