Optic Nerve Sheath Diameter (ONSD) With the Raised PCO2 and Internal Jugular Venous Occlusion

NCT02361658 | Completed Results

• 1 other identifier: UHN REB # 14-8014
• Study Type: observational
• Target: 100
• Locations: 1 country
• Sites: 1

Brief Summary

Monitoring the ICP is the most important aspect of the management of these patients. Recently, transorbital ultrasonography has gained popularity as a noninvasive bedside exam that has been shown to be useful in the diagnosis of raised ICP by evaluating the change in the optic nerve sheath diameter (ONSD). Transorbital ultrasonographic measurement of ONSD appears to be a noninvasive, relatively inexpensive bedside examination for the diagnosis of raised ICP. The investigators aimed to determine the changes in ONSD with acute controlled changes in ICP in healthy volunteers. The controlled changes in ICP will be produced by manipulating the PCO2 with the use of Respiract and jugular venous compression with the use of custom made neck collar.

Conditions

Elevated Intracranial Pressure (ICP)

Outcome Measures

Primary Outcomes (1)

• Changes in ONSD in mm With Changes in ICP in Healthy Volunteers.

  Transorbital ultrasound will be used for measuring the changes in ONSD. The controlled changes in ICP will be produced by manipulating the PCO2 with the use of Respiract and jugular venous compression with the use of custom made neck collar.

  1 day

Interventions

Ultrasonographic of the optic nerve sheath diameter OTHER

On both eyes of all subjects in supine position by two investigators.

RespirAct™ OTHER

Carbon dioxide Manipulation by RespirAct™ sequential gas delivery breathing circuit at each CO2 levels (normocapnia, Hypercapnia I and II and hypocapnia).

Neck collar OTHER

Internal jugular compression using a Neck collar will be applied at each CO2 levels (normocapnia, Hypercapnia I and II and hypocapnia) and ONSD measurements will be done before and after the collar.

Eligibility Criteria

• Age: 18 Years+
• Sex: all
• Healthy Volunteers: Yes
• Age Groups: Adult (18-64), Older Adult (65+)
• Sampling Method: Non-Probability Sample

Study Population

Adult healthy volunteers

You may qualify if:

• Adult healthy volunteers who are above the age of 18 ASA 1 Body mass index (BMI) less than and equal to 35 Neurologically normal subjects with no symptoms other than occasional non-severe headache

You may not qualify if:

• BMI above 35 Lack of informed consent Language barrier Medical students and/or anesthesia residents going through the department as part of their rotation Pregnancy Frequent migraine headache

Sponsors & Collaborators

• Lashmi Venkatraghavan: lead
• University Health Network, Toronto: collaborator

Study Sites (1)

Toronto Western Hospital

Toronto, Ontario, M5T2S8, Canada

Location

MeSH Terms

Conditions

Intracranial Hypertension

Condition Hierarchy (Ancestors)

Brain Diseases; Central Nervous System Diseases; Nervous System Diseases

Results Point of Contact

• Title: Emad Al Azazi
• Organization: Toronto Western Hospital, University Health Network

emad.alazazi@uhnresearch.ca

4166035800

Study Officials

• Lashmi Venkatraghavan, MD

  Assistant Professor, Toronto Western Hospital, University Health Network

  PRINCIPAL INVESTIGATOR

Publication Agreements

• PI is Sponsor Employee: Yes

Study Design

• Study Type: observational
• Observational Model: COHORT
• Time Perspective: PROSPECTIVE
• Sponsor Type: OTHER
• Responsible Party: SPONSOR INVESTIGATOR
• PI Title: Assistant Professor, Department of Anesthesia, Toronto Western Hospital, Toronto, Canada

Study Record Dates

• First Submitted: February 3, 2015
• First Posted: February 12, 2015
• Study Start: January 1, 2015
• Primary Completion: May 1, 2017
• Study Completion: May 1, 2017
• Last Updated: March 17, 2025
• Results First Posted: March 17, 2025

Record last verified: 2025-02

Locations

CA (1)