Arm versus ankle mean arterial pressure during elective cesarean delivery

Observational Study Comparing Non-Invasive Mean Arterial Blood Pressure Measurements at the Arm and Ankle During Elective Cesarean Delivery to Facilitate Skin-to-Skin Contact.

This study will see if a blood pressure cuff on the ankle gives similar mean arterial pressure readings to a standard arm cuff in pregnant people having a planned C-section under spinal anesthesia.

Quick facts

• Study type: Observational
• Enrollment: 110 (estimated)
• Ages: 18 Years and up
• Sex: Female
• Sponsor: St. Justine's Hospital (other)
• Locations: 1 site (Montreal, Quebec)
• Trial ID: NCT07422766 on ClinicalTrials.gov

What this trial studies

This observational study enrolls 110 pregnant individuals (≥35 weeks, singleton) scheduled for elective cesarean under neuraxial anesthesia at CHU Sainte‑Justine. Each participant will wear both a standard upper‑arm cuff and a cuff on the ankle, with simultaneous non‑invasive blood pressure measurements taken before entering the operating room, five minutes after spinal anesthesia, and five minutes after birth. The primary analysis compares mean arterial pressure (MAP) between arm and ankle measurements five minutes after birth; secondary comparisons include pre‑anesthesia and post‑anesthesia timepoints and four yes/no questions on maternal comfort during skin‑to‑skin contact. Every participant serves as her own control.

Who should consider this trial

Good fit: Ideal candidates are term (≥35 weeks) singleton pregnant people scheduled for elective cesarean under neuraxial anesthesia, ASA I–III, BMI under 40, and able to consent in English or French.

Not a fit: Patients with peripheral vascular disease, hypertension requiring medication, morbid obesity (BMI ≥40), those having general anesthesia, emergency or multiple pregnancies, or unable to have an ankle cuff placed are unlikely to benefit from ankle cuff monitoring.

Why it matters

Potential benefit: If ankle MAP readings are comparable to arm readings, ankle cuffs could allow more comfortable and uninterrupted skin‑to‑skin contact after cesarean without sacrificing non‑invasive blood pressure monitoring.

How similar studies have performed: Previous research comparing ankle and arm non‑invasive blood pressure has been performed in other populations and some obstetric settings with mixed results, so the approach is not entirely novel but remains incompletely settled for cesarean patients.

Eligibility criteria

Inclusion Criteria:

* Women scheduled for elective cesarean under neuraxial anesthesia at CHU Sainte-Justine.
* American Society of Anesthesiologists Physical Status I-III
* Singleton pregnancy
* Gestation ≥ 35 weeks
* BMI \< 40
* Able to consent in French or English

Exclusion Criteria:

* Cesarean planned under general anesthesia.
* Multiple pregnancy
* Prematurity \< 35 weeks gestation
* Major fetal anomalies
* Morbid obesity (BMI ≥ 40)
* Active labor
* Emergency cesarean
* Prisoners
* Peripheral vascular disease requiring medication or treatment
* Hypertensive diseases requiring medication
* Inability to place blood pressure cuff on ankle (amputation, dysmorphism, etc.)
* Complications requiring significant hemodynamic support (transfusions, inotropes, multiple vasopressors, etc.

Where this trial is running

Montreal, Quebec

• CHU Sainte-Justine — Montreal, Quebec, Canada (RECRUITING)

Study contacts

• Principal investigator: Valerie Zaphiratos — St. Justine's Hospital
• Study coordinator: Valerie Zaphiratos, MD, MSc, FRCPC, Anesthesiology

Conditions: Pregnancy, Cesarean Delivery, Blood Pressure Measurement in Pregnancy, Skin to Skin Contact, blood pressure, Mean arterial pressure, pregnancy, cesarean