Late Breaking Original Research
Monday, November 13, 2023
01:00 PM–02:30 PM
Abstract
Introduction: Patients with severe trauma often experience extensive acute blood loss and require activation of massive transfusion protocols (MTP) for resuscitation. For a number of reasons, including citrate toxicity, hypocalcemia is a common occurrence in MTP. Hypocalcemia during MTP is associated with increased mortality, however optimal calcium replacement has not been elucidated.
Research Question or Hypothesis: To investigate the ratio of calcium supplementation to blood products administered during MTP to propose a strategy for mitigating hypocalcemia.
Study Design: single-center retrospective case-control
Methods: All patients aged 15 and older with a trauma alert and MTP activation within 4 hours of admission were included. This IRB-approved study was conducted at an urban, level I trauma center between January 1, 2016 and December 31, 2021. Patients who expired in the trauma bay and those who sustained catastrophic head injuries were both excluded. The primary endpoint was the ratio of elemental calcium administered to blood products transfused, stratified by lowest ionized calcium (iCa) level, including severe hypocalcemia (iCa <3.0 mg/dL), hypocalcemia (iCa 3-4 mg/dL), and normocalcemia (iCa >4.0 mg/dL). Additional endpoints included assessment of all-cause inpatient mortality, coagulopathies, and metabolic derangements. Statistical analysis was completed using Shapiro-Wilk, one-way ANOVA, and Chi-squared tests with significance at p<0.05 (SASv9.4).
Results: A total of 259 patients met study criteria, with 84 severely hypocalcemic, 70 hypocalcemic, and 105 normocalcemic. Across all strata, a ratio of 30 mg elemental calcium was replaced per unit of blood product administered, with no statistically significant differences between groups (p=0.460). Secondary outcomes revealed statistically significant metabolic and coagulopathic derangements, worsening with increasing degree of hypocalcemia.
Conclusion: Consistent with prior literature, hypocalcemia was associated with worse outcomes in a trauma population undergoing massive transfusion. Based on these data, we are proposing an empiric replacement of no less than 30 mg elemental calcium per unit of blood transfused for future exploration in our institutional MTP.
Presenting Author
Kaeli Singer PharmD, MBAOhioHealth Grant Medical Center
Authors
Sara Jordan PharmD
Grant Medical Center (OhioHealth)
Josh Hill MD
OhioHealth Grant Medical Center
Mallory Faherty PhD, ATC
OhioHealth Research Institute
Taylor Roberson PharmD
OhioHealth Grant Medical Center