Association Between Preoperative Calcium Levels and the Occurrence of Postoperative PE in Trauma Patients: A Retrospective Multicenter Cohort Study

ABSTRACT Backgrounds Trauma patients who undergo surgery are at high risk for acute pulmonary embolism (PE). We aimed to investigate the connection between the preoperative serum calcium level of trauma patients and their risk of postoperative PE. Methods We included 5598 trauma patients from four centers (2017–2023). Patients were categorized as Hypocalcemia (< 2.2 mmol/L) and Non‐hypocalcemia (≥ 2.2 mmol/L). Propensity score matching (PSM) was used to match Hypocalcemia group and Non‐hypocalcemia group 1:1. We applied logistic regression to determine the correlation between preoperative hypocalcemia and the risk of postoperative PE. We plotted the receiver operating characteristic (ROC) curve to assess the predictive value of preoperative serum calcium levels for postoperative PE. Results The overall incidence of PE in trauma patients was 2.1% (120/5598). Before and after PSM, PE in the Hypocalcemia group was significantly higher than that in the Non‐hypocalcemia group [2.9% vs. 1.6%, p = 0.001] and [2.9% vs. 1.9%, p = 0.039]. Post‐PSM logistic regression revealed that trauma patients with preoperative hypocalcemia had a 1.54‐fold increased risk of postoperative PE formation (95% CI 1.04–2.30, p = 0.032). Within the observed range of this cohort, for every 1 mmol/L increase in preoperative serum calcium, the risk of postoperative PE formation was reduced by 62% (OR 0.38, 95% CI 0.22–0.73; p = 0.001). ROC results showed that the area under the curve (AUC) of preoperative serum calcium in predicting the occurrence of PE was 0.59 (95% CI 0.54–0.64), p = 0.001. Conclusion Preoperative hypocalcemia is significantly associated with an increased risk of postoperative PE formation in trauma patients. Trial Registration ChiCTR2300078097