Calcium Chloride for Prevention of Blood Loss During Intrapartum Cesarean Delivery (CALBLOC)

Stanford University

Status and phase: Completed; Phase 3

Conditions: Cesarean Section Complications; Uterine Atony With Hemorrhage; Uterine Atony; Postpartum Hemorrhage

Treatments: Drug: Saline placebo; Drug: Calcium chloride

Study type: Interventional

Funder types: Other

Identifiers

NCT05027048

MRTG-02-15-2022-Ansari (Other Grant/Funding Number)

62206

YIG-2020 (Other Grant/Funding Number)

Details and patient eligibility

About

Postpartum hemorrhage (PPH) is the leading cause of maternal morbidity and mortality worldwide. Up to 80% of PPH is caused by uterine atony, the failure of the uterine smooth muscle to contract and compress the uterine vasculature after delivery. Laboratory and epidemiological studies show that low extracellular and serum calcium levels, respectively, decrease uterine contractility. A pilot study performed by the investigators supports the hypothesis that intravenous calcium chloride is well tolerated and may have utility in preventing uterine atony. The proposed research will establish the relationship between uterine tone and calcium through a clinical trial with an incorporated pharmacokinetic and pharmacodynamic (PK/PD) study. In a randomized, placebo-controlled, double-blind trial, investigators will establish the effect of 1 gram of intravenous calcium chloride upon quantitative blood loss and uterine tone during cesarean delivery in parturients with high risk of uterine atony. Investigators will concurrently collect serial venous blood samples to measure calcium for PK/PD modeling in this pregnant study cohort. High-quality clinical research and development of novel therapeutics to manage uterine atony are critical to reduce the high maternal morbidity and mortality from PPH.

Enrollment: 120 patients

Sex: Female

Ages: 18 to 55 years old

Volunteers: No Healthy Volunteers

Inclusion criteria

• Patient had a trial of labor for vaginal delivery prior to cesarean
• Patient received an oxytocin infusion for labor augmentation or induction prior to cesarean

Exclusion criteria

• renal dysfunction with serum Cr >1.0 mg/dL
• known underlying cardiac condition
• treatment with digoxin within the last 2 weeks for a maternal or fetal indication
• treatment with a calcium channel blocker medication within 24 hours
• hypertension necessitating intravenous antihypertensive medication within 24 hours
• emergent case in which study participation could in any way impede patient care by the judgement of the obstetrician, anesthesiologist, or bedside nurse

Trial design

Primary purpose: Prevention

Allocation: Randomized

Interventional model: Parallel Assignment

Masking: Quadruple Blind

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120 participants in 2 patient groups, including a placebo group

Calcium chloride

Experimental group

Description:

1 gram of calcium chloride in total volume 60mL with sterile saline, delivered over 10 minute controlled infusion at a constant rate (360mL/hour) beginning 2 minutes after fetal delivery and 1 minute after delayed cord clamp. This intervention occurs IN ADDITION TO standard care with oxytocin 2 unit bolus and infusion at 7.5 units per hour which begins immediately after fetal delivery.

Treatment:

Drug: Calcium chloride

Saline placebo

Placebo Comparator group

Description:

60mL sterile saline, delivered over 10 minute controlled infusion at a constant rate (360mL/hour) beginning 2 minutes after fetal delivery and 1 minute after delayed cord clamp. This intervention occurs IN ADDITION TO standard care with oxytocin 2 unit bolus and infusion at 7.5 units per hour which begins immediately after fetal delivery.

Treatment:

Drug: Saline placebo