Hormonally active women tolerate shock-trauma better than do men: a prospective study of over 4000 trauma patients

Abstract

Objective: To test the hypothesis that comparably injured women, especially those in the hormonally active age groups, would manifest a better preserved hemodynamic response and tissue perfusion after major trauma than do men.

Summary background data: The notion that premenopausal women are more resistant than men to shock and trauma has been shown in numerous preclinical models. However, human studies on the effects of gender on outcome after shock-trauma are less clear, and none has examined the effect of gender on the immediate postinjury response to major trauma.

Methods: Prospective series of all patients at a Level I trauma center from January 2000 to December 2005. Study patients were all patients arriving to the trauma area of the emergency department and having a serum lactate drawn within 30 minutes of arrival. Demographic data, injury severity indices, blood utilization, and lactate levels were recorded. Lactate was used as a marker of the hemodynamic response to injury, because it has been shown to be an excellent and accurate indicator of inadequate tissue perfusion.

Results: : A total of 5192 patients were eligible for the study of which 4106 fulfilled the study requirements and were enrolled. Initial serum lactate levels were significantly lower in premenopausal (age 14-44) and perimenopausal (age 45-54) women than in men of the same age groups (P < 0.001), even though the Injury Severity Score of the women was significantly higher than that of the men (24 vs. 18; P < 0.1). When patients were stratified into major injury groups as well as groups receiving blood transfusions, the premenopausal women were also found to have lower initial serum lactate levels and receive less blood, while having a greater magnitude of injury as reflected in their Injury Severity Score.

Conclusion: The data firmly establishes a proof of principle that hormonally active human women have a better physiologic response to similar degrees of shock and trauma than do their male counterparts. These gender-based differences should be taken into account in designing studies evaluating the response to shock-trauma.

FIGURE 1. Summary of patient population and enrollment.

FIGURE 2. Women received less blood both during the initial 24 hour postinjury period as well as during their hospital course even though they had a higher ISS. *P < 0.01.

FIGURE 3. Twenty-four lactate clearance in 462 patients showing that males clear their lactates such that their levels become comparable to women. Data expressed as mean with 95% confidence intervals.

FIGURE 4. Women sustaining major trauma received less blood both during the initial 24 hour postinjury period (P = 0.24) as well as during their hospital course even though they had a higher ISS. *P < 0.01.