Pharmacokinetics, Postpartum Hemorrhage, Pregnancy
Conditions
Keywords
calcium, oral calcium, calcium carbonate, calcium pharmacokinetics, pharmacokinetics in pregnancy, postpartum hemorrhage, ionized calcium, pharmacokinetics
Brief summary
This study investigates the time course of change in calcium in the blood after a pregnant subject takes an oral dose of calcium carbonate (commonly marketed as "Tums"). Midway through the trial, with IRB permission, the oral calcium formulation was switched to calcium citrate to test whether this, better-absorbed formulation might prove more effective in increasing serum calcium. This information is important for trials investigating whether oral calcium can reduce postpartum hemorrhage, bleeding after delivery.
Interventions
DRUGOral calcium carbonate
Participants receive a single, open-label dose of oral calcium carbonate 1200mg
DRUGOral calcium citrate
Participants receive a single oral dose of calcium citrate 1250mg
Sponsors
Stanford University
Study design
Allocation
NON_RANDOMIZED
Intervention model
SINGLE_GROUP
Primary purpose
OTHER
Masking
NONE
Intervention model description
This is a single arm pharmacokinetic trial. No efficacy outcomes are analyzed. The aim of the study is to determine the pharmacokinetics of a single dose of oral calcium carbonate or calcium citrate in parturients. The outcome of interest is serial measurement of the ionized calcium in the blood.
Eligibility
Sex/Gender
FEMALE
Age
18 Years to 45 Years
Healthy volunteers
No
Inclusion criteria
* Pregnant female subjects at the study institution, admitted for labor (spontaneous, augmented, or induced)
Exclusion criteria
1. severe range blood pressure (BP \>160/\>110) within the 48 hours prior to delivery 2. patient age \<18 years or \>45 years 3. renal dysfunction with a documented serum Cr \> 1.0 mg/dL 4. known history of congenital or acquired cardiac disease or history of arrhythmia 5. patient taking digoxin 6. patient currently taking a calcium channel blocker 7. Weight \<55kg or \>100kg, or 8. receiving magnesium infusion within 24 hours prior to or during cesarean delivery 9. Prior or planned administration of calcium by the obstetric or anesthesiology teams for clinical indications within 24 hours of study enrollment 10. Patient took a calcium supplement in the past 48 hours 11. Patient status is NPO (nothing by mouth) as ordered by the clinical team
Design outcomes
Primary
| Measure | Time frame | Description |
|---|---|---|
| Ionized calcium concentration | 4 hours | Ionized calcium (mmol/L) is measured at baseline and over 5 additional convenience timepoints over the 4 hours after ingestion of calcium carbonate 3000mg. |
Countries
United States
Contacts
PRINCIPAL_INVESTIGATORJessica Ansari, MD, MS
Stanford University
Outcome results
None listed