(1749) The Reports of Our Hypocalcemia Are Greatly Exaggerated

Introduction: Hypocalcemia occurs in trauma patients at a rate of 23-56% in previous smaller studies. We aim to describe the incidence of hypocalcemia in a large set of trauma patients and the association of calcium levels with hemodynamics, transfusion requirements, coagulopathy, number of procedures, and mortality at our institution.

Methods: This was an IRB approved retrospective chart review from January 2021 to December 2021 of level 1 and 2 trauma activations aged 16 years or older that had ionized calcium (iCal) levels drawn in the trauma bay. We determined the incidence of hypocalcemia (iCal < 4.0 mg/dL) and compared normal (iCal >4.0 mg/dL), moderate (iCal 3.0-4.0 mg/dL), and severe (iCal < 3.0 mg/dL) cohorts. Outcomes included initial shock index, transfusion requirements, thromboelastogram (TEG) derangements, number of invasive trauma bay procedures performed, and mortality.

Results: 2334 patients were included. Average age was 45 ± 21. 1486 (64%) were male. 314 (13%) had penetrating injuries. 62 (2.7%) had hypocalcemia. 10 and 52 of the patients with hypocalcemia were in the severe and moderate cohort, respectively. Patients with severe hypocalcemia were more likely to have severe shock index (p < 0.001). Average units of PRBCs, platelets, FFP, and cryoprecipitate transfused were significantly different between the severe (12, 2.6, 9.7, 0.4, respectively), moderate (1.7, 0.3, 1.1, 0.15, respectively) and normal (0.5, 0.06, 0.2, 0.02, respectively) cohorts (p < 0.001). TEG derangements differed in the severe (100%), moderate (33.3%), and normal (33.0%) cohorts (p < 0.001). Number of procedures varied between the severe (2.1), moderate (1.1), and normal (0.5) cohorts (p < 0.001). Different rates of mortality were seen in the severe (70%), moderate (19.2%), and normal (4.5%) cohorts (p < 0.001). Patients with hypocalcemia were over 3 times more likely to have in-hospital mortality (OR 3.18, p=0.006).

Conclusions: In our population, the largest sample size published to date, the incidence of hypocalcemia was 2.7%, nearly ten times lower than previously reported. Worsening hypocalcemia was associated with increased transfusion requirements, coagulopathy, invasive procedures, and was found to be an independent predictor of mortality.