Dexamethasone Versus Ondansetron for Preventing Post-Spinal Hypotension in Preeclampsia

NCT07793760 | Not Yet Recruiting Phase 4

• 1 other identifier: Dex vs Ondan: Spinal BP in PE
• Study Type: interventional
• Target: 110
• Locations: 0 countries
• Sites: N/A

Brief Summary

This study compares the efficacy and safety of intravenous dexamethasone versus intravenous ondansetron in preventing low blood pressure (hypotension) following spinal anesthesia in pregnant women with preeclampsia undergoing scheduled cesarean delivery. Spinal anesthesia is the preferred anesthetic method for cesarean delivery, but it frequently causes a sudden drop in maternal blood pressure. In patients with preeclampsia, post-spinal hypotension can compromise blood flow to the placenta and vital organs. While traditional vasopressor medications are used to restore blood pressure, non-adrenergic prophylactic agents such as dexamethasone and ondansetron may help maintain hemodynamic stability through different physiological pathways. Participants will be randomly assigned to receive either intravenous dexamethasone (8 mg) or intravenous ondansetron (4 mg) 15 minutes prior to the initiation of spinal anesthesia. Blood pressure, heart rate, vasopressor requirements, optic nerve sheath diameter, and maternal and neonatal outcomes will be monitored throughout the surgery and during the immediate postoperative period.

Conditions

Preeclampsia; Spinal Anesthesia-Induced Hypotension; Cesarean Section

Keywords

Dexamethasone; Ondansetron; Post-Spinal Hypotension; Preeclampsia; Spinal Anesthesia; Cesarean Delivery; Optic Nerve Sheath Diameter; Vasopressors

Outcome Measures

Primary Outcomes (1)

• Incidence of post-spinal hypotension

  Number of participants with a decrease in systolic blood pressure below 80% of baseline.

  1 hour

Study Arms (2)

Group D: Dexamethasone

EXPERIMENTAL

Patients in Group D will receive intravenous dexamethasone 8 mg diluted with 0.9% normal saline to a total volume of 10 mL, administered slowly over approximately one minute, 15 minutes before the induction of spinal anaesthesia.

Drug: Dexamethasone

Group O: Ondansetron

ACTIVE COMPARATOR

Patients in Group O will receive intravenous ondansetron 4 mg diluted with 0.9% normal saline to a total volume of 10 mL, administered slowly over approximately one minute, 15 minutes before the induction of spinal anaesthesia.

Drug: Ondansetron

Interventions

Dexamethasone DRUG

Intravenous dexamethasone 8 mg diluted with 0.9% normal saline to a total volume of 10 mL, administered slowly over approximately one minute, 15 minutes before the induction of spinal anesthesia.

Group D: Dexamethasone

Ondansetron DRUG

Intravenous ondansetron 4 mg diluted with 0.9% normal saline to a total volume of 10 mL, administered slowly over approximately one minute, 15 minutes before the induction of spinal anesthesia.

Group O: Ondansetron

Eligibility Criteria

• Age: 18 Years - 40 Years
• Sex: female
• Healthy Volunteers: No
• Age Groups: Adult (18-64)

You may qualify if:

• Pregnant women aged 18 to 40 years.
• American Society of Anesthesiologists (ASA) physical status III.
• Diagnosed with preeclampsia (new onset of hypertension ≥140/90 mmHg with proteinuria occurring after 20 weeks of gestation according to ACOG and ISSHP guidelines).
• Scheduled for elective cesarean delivery under spinal anesthesia.

You may not qualify if:

• Peripartum bleeding.
• Obesity (body mass index ≥40 kg/m²).
• Coagulation disorders (platelet count \< 75,000/μL).
• Neurological disorders.
• Previous or current systemic corticosteroid therapy.
• Known cardiac disease.
• History of diabetes mellitus.
• Renal dysfunction (serum creatinine \> 2 mg/dL).
• Hepatic dysfunction (serum liver enzymes \> 2 times the upper limit of normal).
• Known hypersensitivity to dexamethasone, ondansetron, or any component of the study medications.
• Emergency cesarean delivery.
• Known fetal congenital anomalies.

Sponsors & Collaborators

• Assiut University: lead

MeSH Terms

Conditions

Pre-Eclampsia

Interventions

Dexamethasone; Ondansetron

Condition Hierarchy (Ancestors)

Hypertension, Pregnancy-Induced; Pregnancy Complications; Female Urogenital Diseases and Pregnancy Complications; Urogenital Diseases

Intervention Hierarchy (Ancestors)

Pregnadienetriols; Pregnadienes; Pregnanes; Steroids; Fused-Ring Compounds; Polycyclic Compounds; Steroids, Fluorinated; Imidazoles; Azoles; Heterocyclic Compounds, 1-Ring; Heterocyclic Compounds; Carbazoles; Indoles; Heterocyclic Compounds, 2-Ring; Heterocyclic Compounds, Fused-Ring; Heterocyclic Compounds, 3-Ring

Study Design

• Study Type: interventional
• Phase: phase 4
• Allocation: RANDOMIZED
• Masking: QUADRUPLE
• Who Masked: PARTICIPANT, CARE PROVIDER, INVESTIGATOR, OUTCOMES ASSESSOR
• Purpose: PREVENTION
• Intervention Model: PARALLEL
• Sponsor Type: OTHER
• Responsible Party: PRINCIPAL INVESTIGATOR
• PI Title: Resident of Anaesthesia, ICU and Pain Management

Study Record Dates

• First Submitted: August 26, 2026
• First Posted: August 31, 2026
• Study Start: October 1, 2026
• Primary Completion (Estimated): October 1, 2027
• Study Completion (Estimated): November 1, 2027
• Last Updated: August 31, 2026

Record last verified: 2026-08