Sex dimorphic outcomes after whole blood resuscitation in trauma patients: a national database study

Injured females experience improved outcomes after component therapy resuscitation. We hypothesize that females <52 transfused with whole blood (WB) have improved survival, lower blood utilization, and lower complication rates compared with males and females ≥52.

This retrospective analysis assessed Trauma Quality Improvement Program Participant Use File patients aged 18-90 transfused WB 1/1/2020-12/31/2022. Patients who were pregnant, transferred, anticoagulated, died <1 hour, had a blood dyscrasia, or severe head injury were excluded. Outcomes were compared between: female and male patients <52, female and male patients ≥52, and females <52 and ≥52, separated by injury mechanism. Univariate and multivariate analyses were applied, with the latter controlled for injury factors, race, medical history, time to hemorrhage control procedure, and complications.

15 051 patients met inclusion. Male sex was associated with greater need for massive transfusion, higher blood product utilization, and acute kidney injury than females, regardless of mechanism (p<0.05, all comparisons). Among those injured by blunt mechanism, females received fewer of all individual blood component transfusions than males at all ages (all p<0.01). Females <52 with blunt mechanisms had equivalent mortality compared with males, whereas females ≥52 had decreased mortality (20.1% vs 24.2%, p=0.01). Compared with females ≥52, younger females had lower mortality (14% vs 20.1%, p<0.01) after blunt injury despite having worse injuries and receiving more component transfusions. These differences were not seen in patients injured by penetrating mechanism. On multivariable analysis, mortality was higher in males and females ≥52 compared with younger females (all p<0.01), regardless of mechanism.

After WB, being female and younger was generally associated with fewer blood transfusions, complications, and mortalities, but these differences were more pronounced in those with blunt mechanism. Females <52 demonstrated lower mortality compared with older patients. Further investigation is required to elucidate the mechanisms of these findings.

III, Prognostic/Epidemiological.