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Effect of Intravenous or Intraosseous Calcium vs Saline on Return of Spontaneous Circulation in Adults With
Mikael Fink Vallentin1, Asger Granfeldt2, Carsten Meilandt1
1Prehospital Emergency Medical Services, Central Denmark Region, Aarhus.
Insights
Administration of calcium during out-of-hospital cardiac arrest did not improve return of spontaneous circulation in adults. The trial was stopped early due to concerns about harm, with no significant benefits observed for survival or neurological outcomes.
Area of Science:
- Emergency Medicine
- Cardiology
- Clinical Trials
Background:
- The efficacy of calcium administration in cardiac arrest patients remains uncertain.
- Out-of-hospital cardiac arrest (OHCA) presents a critical medical emergency with significant mortality.
Purpose of the Study:
- To investigate if calcium administration improves return of spontaneous circulation (ROSC) in adults experiencing OHCA.
Main Methods:
- A double-blind, placebo-controlled randomized clinical trial involving 397 adult OHCA patients.
- Intervention: intravenous or intraosseous calcium chloride versus saline, administered with epinephrine.
- Primary outcome: sustained ROSC; secondary outcomes: survival and neurological function at 30 and 90 days.
Main Results:
- The trial was halted early due to safety concerns in the calcium group.
- No significant difference in sustained ROSC between calcium (19%) and saline (27%) groups (RR, 0.72; P=.09).
- No significant improvements in survival or favorable neurological outcomes were observed in the calcium group. Hypercalcemia was noted in 74% of patients with ROSC in the calcium group.
Conclusions:
- Calcium administration did not enhance sustained ROSC in adult OHCA patients.
- The findings do not support the use of calcium during OHCA in adults.
- Concerns regarding potential harm warrant caution in calcium use during cardiac arrest.
Importance:
It is unclear whether administration of calcium has a beneficial effect in patients with cardiac arrest.
Objective:
To determine whether administration of calcium during out-of-hospital cardiac arrest improves return of spontaneous circulation in adults.
Design, Setting, And Participants:
This double-blind, placebo-controlled randomized clinical trial included 397 adult patients with out-of-hospital cardiac arrest and was conducted in the Central Denmark Region between January 20, 2020, and April 15, 2021. The last 90-day follow-up was on July 15, 2021.
Interventions:
The intervention consisted of up to 2 intravenous or intraosseous doses with 5 mmol of calcium chloride (n = 197) or saline (n = 200). The first dose was administered immediately after the first dose of epinephrine.
Main Outcomes And Measures:
The primary outcome was sustained return of spontaneous circulation. The secondary outcomes included survival and a favorable neurological outcome (modified Rankin Scale score of 0-3) at 30 days and 90 days.
Results:
Based on a planned interim analysis of 383 patients, the steering committee stopped the trial early due to concerns about harm in the calcium group. Of 397 adult patients randomized, 391 were included in the analyses (193 in the calcium group and 198 in the saline group; mean age, 68 [SD, 14] years; 114 [29%] were female). There was no loss to follow-up. There were 37 patients (19%) in the calcium group who had sustained return of spontaneous circulation compared with 53 patients (27%) in the saline group (risk ratio, 0.72 [95% CI, 0.49 to 1.03]; risk difference, -7.6% [95% CI, -16% to 0.8%]; P = .09). At 30 days, 10 patients (5.2%) in the calcium group and 18 patients (9.1%) in the saline group were alive (risk ratio, 0.57 [95% CI, 0.27 to 1.18]; risk difference, -3.9% [95% CI, -9.4% to 1.3%]; P = .17). A favorable neurological outcome at 30 days was observed in 7 patients (3.6%) in the calcium group and in 15 patients (7.6%) in the saline group (risk ratio, 0.48 [95% CI, 0.20 to 1.12]; risk difference, -4.0% [95% CI, -8.9% to 0.7%]; P = .12). Among the patients with calcium values measured who had return of spontaneous circulation, 26 (74%) in the calcium group and 1 (2%) in the saline group had hypercalcemia.
Conclusions And Relevance:
Among adults with out-of-hospital cardiac arrest, treatment with intravenous or intraosseous calcium compared with saline did not significantly improve sustained return of spontaneous circulation. These results do not support the administration of calcium during out-of-hospital cardiac arrest in adults.
Trial Registration:
ClinicalTrials.gov Identifier: NCT04153435.
