Defining the optimal calcium repletion dosing in patients requiring activation of massive transfusion protocol.

PURPOSE: Massive transfusion protocols (MTP) commonly result in severe hypocalcemia due to the calcium-binding affinity of citrate in blood components. The purpose of this study is to determine the optimal grams (g) of citrate to repletion calcium (Ca) milliequivalents (mEq) (Citrate:Ca) ratio to reduce 30-day mortality. METHODS: This was a retrospective, single-centered, cohort study at a level 1 trauma center evaluating trauma and surgical patients in need of MTP activation from January 1, 2010-July 31, 2021. Patients with severe hypocalcemia at baseline, defined as ionized calcium (iCa) <0.9 mmol/L, were compared to patients without severe hypocalcemia. The primary endpoint was to determine the optimal ratio of grams of citrate to calcium mEq to reduce mortality in patients receiving a MTP. Secondary endpoints included mortality at 24 h and 30 days, blood components used in MTP, and type of calcium used. RESULTS: Overall, 501 patients were screened for inclusion. Of these patients, 193 were excluded, leaving 308 patients, of which 165 patients (53.6%) had an iCa <0.9 mmol/L within 24 h and 143 patients (46.4%) had iCa ≥0.9 mmol/L within 24 h. The ratio of Citrate:Ca for each patient was not significantly associated with mortality at 24 h (P = 0.79) or 30 days (P = 0.91) at a repletion Citrate:Ca ratio of median 1.97 (IQR 1.14-2.91). The rate of mortality was lowest at a Citrate:Ca of 2 in both <24-h mortality and 30-day mortality. CONCLUSIONS: There were no differences in 24 h or 30 day mortality based on repletion ratios seen in this study. A Citrate:Ca ratio between 2 and 3 in patients undergoing MTP was sufficient to obtain a normalized iCa within 24 h of MTP activation regardless of baseline iCa level. Further prospective studies will be needed to determine the optimal Citrate:Ca ratio.

Acute bilateral hearing loss as a rare presentation of acute stroke.

Acute bilateral hearing loss is an uncommon presentation in the Emergency Department (ED), with a variety of potential causes. It is important to consider neurologic vascular etiologies as a cause for acute sensorineural hearing loss. We report a case of acute hemorrhagic stroke presenting as acute bilateral hearing loss. A 60-year-old male with a history of atrial fibrillation presented to the ED with the acute onset of bilateral hearing loss with otherwise intact neurologic testing. He was found to have an acute left temporal hemorrhagic stroke, and magnetic resonance imaging demonstrated multifocal ischemia including an acute right temporal ischemic stroke. In the ED setting, cerebrovascular pathology is an important consideration in the patient presenting with acute hearing loss in the absence of an alternative diagnosis. Missing such a diagnosis can lead to significant morbidity and mortality.