Hypocalcemia as a predictor of mortality and transfusion. A scoping review of hypocalcemia in trauma and hemostatic resuscitation
BACKGROUND Calcium plays an essential role in physiologic processes, including trauma's "Lethal Diamond." Thus, inadequate serum calcium in trauma patients exacerbates the effects of hemorrhagic shock secondary to traumatic injury and subsequently poorer outcomes compared to those with adequate calcium levels. Evidence to date supports the consideration of calcium derangements when assessing the risk of mortality and the need for blood product transfusion in trauma patients. This review aims to further elucidate the predictive strength of this association for future treatment guidelines and clinical trials. METHODS Publications were collected on the relationship between i-Ca and the outcomes of traumatic injuries from PubMed, Web of Science, and CINAHL. Manuscripts were reviewed to select for English language studies. Hypocalcemia was defined as i-Ca <1.2 mmol/L. RESULTS Using PRISMA guidelines, we reviewed 300 studies, 7 of which met our inclusion criteria. Five papers showed an association between hypocalcemia and mortality. CONCLUSIONS In adult trauma patients, there has been an association seen between hypocalcemia, mortality, and the need for increased blood product transfusions. It is possible we are now seeing an association between low calcium levels prior to blood product administration and an increased risk for mortality and need for transfusion. Hypocalcemia may serve as a biomarker to show these needs. Therefore, hypocalcemia could potentially be used as an independent predictor for multiple transfusions such that ionized calcium measurements could be used predictively, allowing faster administration of blood products.
A Novel, Perfused-Cadaver Simulation Model for Tourniquet Training in Military Medics
Journal of special operations medicine : a peer reviewed journal for SOF medical professionals. 2018;18((4):):97-102.
BACKGROUND Exsanguinating limb injury is a significant cause of preventable death on the battlefield and can be controlled with tourniquets. US Navy corpsmen rotating at the Navy Trauma Training Center receive instruction on tourniquets. We evaluated the effectiveness of traditional tourniquet instruction compared with a novel, perfused-cadaver, simulation model for tourniquet training. METHODS Corpsmen volunteering to participate were randomly assigned to one of two tourniquet training arms. Traditional training (TT) consisted of lectures, videos, and practice sessions. Perfused-cadaver training (PCT) included TT plus training using a regionally perfused cadaver. Corpsmen were evaluated on their ability to achieve hemorrhage control with tourniquet(s) using the perfused cadaver. Outcomes included (1) time to control hemorrhage, (2) correct placement of tourniquet(s), and (3) volume of simulated blood loss. Participants were asked about confidence in understanding indications and skills for tourniquets. RESULTS The 53 corpsmen enrolled in the study were randomly assigned as follows: 26 to the TT arm and 27 to the PCT arm. Corpsmen in the PCT group controlled bleeding with the first tourniquet more frequently (96% versus 83%; p < .03), were quicker to hemorrhage control (39 versus 45 seconds; p < .01), and lost less simulated blood (256mL versus 355mL; p < .01). There was a trend toward increased confidence in tourniquet application among all corpsmen. CONCLUSIONS Using a perfused- cadaver training model, corpsmen placed tourniquets more rapidly and with less simulated-blood loss than their traditional training counterparts. They were more likely to control hemorrhage with first tourniquet placement and gain confidence in this procedure. Additional studies are indicated to identify components of effective simulation training for tourniquets.