Optic Nerve Sheath Diameter in Pre-Eclamptic Parturient Receiving Magnesium Sulfate Combined With Dexmedetomidine

Not Applicable

Completed

• Conditions: Optic Nerve Sheath Diameter; Preeclampsia Severe
• Interventions: Drug: Saline; Drug: Dexmedetomidine

• Registration Number: NCT05610774
• Lead Sponsor: Benha University

Brief Summary

Dexmedetomidine was reported to effectively reduce cerebral metabolism and ICP by decreasing cerebrospinal fluid pressure in patients with cerebral tumors or head injuries that require craniotomy. However, it was also reported to exhibit no effect on ICP. the effect of MgSO4 associated with dexmedetomidine on ONSD in severely pre-eclamptic parturient has been understudied . Though this study aims to evaluate the effect of dexmedetomidine infusion on raised ICP in severely pre-eclamptic parturients using ocular ultrasonography to determine ONSD as a measure of ICP.

Detailed Description

Dexmedetomidine, a highly selective α-2-receptor agonist, is a first-line sedative medication in ICU and has been increasingly used for obstetric anesthesia. Dexmedetomidine, which provides light sedation, possesses analgesic, sympatholytic, anxiolytic properties and attenuates the stress response without significant respiratory depression. In addition, dexmedetomidine-induced stimulation of postsynaptic alpha-2 adrenergic receptor on the cerebral blood vessels can cause cerebral vasoconstriction and decrease cerebral blood flow. However, the effects of dexmedetomidine on ICP are controversial.

Clinical signs of raised ICP are not specific and often difficult to interpret, especially during pregnancy and pre-eclampsia. Though the use of invasive devices is considered a gold standard in the measurement of ICP, Ocular sonography is a promising bedside tool, which serves as a noninvasive, readily available, and cost-effective means for indirectly measuring ICP.

Bedside ultrasound can be used as a point-of-care tool for rapidly measuring the optic nerve sheath diameter (ONSD), which is a validated indirect means for measuring ICP. An increase in ICP reflects as a raised ONSD since the optic nerve is surrounded by Dural sheath and cerebrospinal fluid (CSF) containing subarachnoid space, which is distensible in the retrobulbar segment, particularly when CSF pressures rise.

Study Timeline

• Study First Submitted: 2022-11-01
• Study First Submitted QC: 2022-11-08
• Study First Posted: 2022-11-09
• Study Start: 2023-06-06
• Primary Completion: 2024-05-10
• Study Completion: 2024-06-15
• Status Verified: 2025-05
• Last Update Submitted: 2025-05-20
• Last Update Posted: 2025-05-23

Recruitment & Eligibility

• Status: COMPLETED
• Sex: Female
• Target Recruitment: 50

Inclusion Criteria

• aged18 to 40 years with
• at least 36 weeks gestation
• admitted with diagnosis of severe pre-eclampsia and scheduled to receive Magnesium Sulphate therapy before delivery

Exclusion Criteria

• Presence of ocular wound or Prior ocular surgery
• emergency cases, and evidence of fetal compromise
• HELLP syndrome (hemolysis, elevated liver enzymes, and low platelet levels)
• Chronic hypertension
• Hyperthyroidism, and diabetes mellitus
• Presence of pre-existing chronic lung and/or cardiac diseases
• Presence of pre-existing chronic renal and/or hepatic diseases
• Presence of any chronic diseases of central nervous system.
• known allergies to the tested drug.

Study & Design

• Study Type: INTERVENTIONAL
• Study Design: PARALLEL

Arm && Interventions

Group	Intervention	Description
Group (C)	Saline	patients will receive saline loading and infusion
Group (D)	Dexmedetomidine	Patients will receive a loading dose of iv dexmedetomidine followed by a maintenance infusion.

Primary Outcome Measures

Name	Time	Method
Optic nerve sheath diameter (ONSD) measurments following Drug administration	Baseline (before starting MgSO4 therapy) then at 1, 6, 12 and 24 hours postoperative

Secondary Outcome Measures

Name	Time	Method
The incidence of raised ICP in severe pre-eclampsia	Baseline (before starting MgSO4 therapy), and during 24 hours postoperative.	ONSD \>5.0 mm
Heart Rate (HR)	Baseline (before starting MgSO4 therapy) then every 2 hours till 24 postoperative hours
The duration of hospital stay	one month after delivery	defined as time from the day of operation to the day of discharge
Sedation Score	every 2 hours after drug infusion, till 24 postoperative hours	the Richmond Agitation and Sedation Scale (RASS), on which scores range from -5 \[unresponsive\] to +4 \[combative\].
mean arterial pressure (MAP) changes.	Baseline (before starting MgSO4 therapy) then every 2 hours till 24 postoperative hours

Trial Locations

Locations (1)

Samar Rafik Amin; 🇪🇬 Banhā, Qalubia, Egypt