Showing papers by "Robert F. Lavery published in 2007"

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

Abstract: Emerging data describes a sexual dimorphism in the response to major injury or sepsis with differences demonstrated in immune function as well as susceptibility to organ injury and infection.1,2 These differences have been attributed to sex hormones, with the female sex hormone estradiol conferring protection and the male sex hormone testosterone increasing susceptibility to injury.1,2 Although some epidemiologic studies suggest that women survive sepsis better than men,3 the notion that gender might influence the clinical outcome after trauma or sepsis was largely ignored until experimental studies from Dr. Chaudry's laboratory documented that sex hormones modulate the immune response to shock and sepsis as well as improve survival.2 Since then, multiple clinical studies have seemed evaluating the influence of gender on survival, the development of organ failure, or infection after major trauma.4–14 Although the results of these epidemiologic trauma studies vary, with some showing gender-based benefits and others showing no differences between the sexes, certain general trends seem to exist. First, there seems to be a trend toward increased survival for younger (premenopausal) women which seems to be present only in women with more severe injuries.7,9,12 Additionally, several of the studies indicate that the incidence of posttraumatic infection and the multiple organ dysfunction syndrome (MODS) is less in the younger premenopausal female population suggesting that the reduced incidence of MODS may, at least in part, contribute to the lower mortality rate observed. In light of emerging clinical studies and the work of Chaudry, we began experimental studies testing the basic hypothesis that female rats would be more resistant to acute trauma-hemorrhagic shock-induced gut and lung injury than would male rats.1 These gender studies confirmed that it is not only being female that is protective, but that the protection is related to the hormonal status of the rat at the time of injury. That is, the resistance to trauma-hemorrhage-induced organ injury varies over the estrus cycle with maximal protection during the proestrus and estrus stages of the cycle when estrogen levels are highest.15 Conversely, rats at the diestrus stage of the cycle, when sex hormones are lowest, demonstrate a degree of gut and lung injury that nearly approaches that of male rats.3 Thus, experimentally, there seems to be a clear, graded response to trauma-hemorrhage-induced organ injury that is related to the hormonal status of the rat at the time of injury. Given this rodent data, we believe that the results of the human studies become a little easier to interpret. Firstly, because the benefit of being female seems to exist primarily in the reproductive years, studies examining gender dimorphism to injury need to segregate hormonally active female patients as the potential cohort most likely to have a beneficial outcome. Additionally, it is important to recognize that hormonal status is severely altered following critical injury and illness.16,17 For example, Woolf et al have shown that estradiol levels in hormonally active women decreased markedly after injury,18 with postinjury estrogen levels approaching those seen in control postmenopausal women. This observation that female sex hormones decrease markedly over the first several days after a major injury would suggest that the maximal benefit to being female would primarily exist during the initial injury period. Consequently, we believed that studies looking at the effect of gender on outcome focusing on the immediate postinjury period would be most likely to identify sex hormone and gender-related differences in outcome. Thus, in the current study, we examined gender dimorphism in the early response to injury, as reflected by plasma lactate levels obtained within 30 minutes of hospital arrival as well as the need for early postinjury blood transfusions. Serum lactate levels were chosen as a marker of the hemodynamic response to injury, because serum lactate has been shown to be an excellent marker of inadequate tissue perfusion as well as a prognostic factor.19,20

Isolated thoracolumbar transverse process fractures: call physical therapy, not spine.

Abstract: Background Historically, thoracolumbar spine transverse process fractures (TVPFx) found on "plain films" of the spine were occasionally associated with occult, mechanically significant vertebral fractures. Thus, "log-roll precautions" have been used pending formal spine evaluation and further imaging. As integrated helical computed tomography (CT) scans of the torso have become routine screening tools in high-energy trauma, TVPFx have been diagnosed with far greater frequency. Yet, where no associated spine injuries are found initially, such isolated TVPFx appear to be benign. Methods We retrospectively reviewed the diagnosis and management of TVPFx in a large Level I trauma center in the period between 2002 and 2005. Of 314 patients with TVPFx who survived more than 48 hours, 17% had fractures of the weight-bearing columns of the thoracolumbar spine noted on the same CT scan and were excluded from study. The management and outcome of the remaining "isolated" TVPFx were assessed by review of trauma registry and charted data. Results The 248 patients included sustained 2.3 +/- 1.5 (SD) TVPFx. They spent 29 hours +/- 32 hours on log-roll precautions while being evaluated by spine consultants and "cleared" before initiating physical therapy. Despite this prolonged immobilization and substantial further investigation, none of the patients with TVPFx judged to be isolated on the basis of screening truncal CT scan proved to have a missed injury of a major vertebral element on further study. Conclusions Isolated thoracolumbar TVPFx are found frequently when helical CT scan is used to screen the torso after high-energy injury. TVPFx are usually multiple. They can be markers for visceral injuries, and in this study, 17% were associated with "significant" fractures. TVPFx require careful pain management and benefit by early mobilization. Yet, where no other vertebral fracture is seen on an adequate screening CT scan, investigation may reasonably end. Further imaging and consultations with spine services waste scarce resources, and lead to prolonged log-roll precautions, which delay mobilization and are potentially deleterious to overall patient care.