Clinical trial NCT02361658: Optic Nerve Sheath Diameter (ONSD) With the Raised PCO2 and Internal Jugular Venous Occlusion
Official title: Ultrasonographic Assessment of the Optic Nerve Sheath Diameter During Variations in PetCO2 and Controlled Internal Jugular Venous Occlusion: A Volunteer Study
Study type: OBSERVATIONAL
Overall status: COMPLETED
Conditions: Elevated Intracranial Pressure (ICP)
Lead sponsor: University Health Network, Toronto
Sponsor class: OTHER
Collaborators: name: University Health Network, Toronto
First posted: 2015-02-12
Enrollment: 100
Sex: ALL
Minimum age (years): 18
Standard ages: ADULT
OLDER_ADULT
Accepts healthy volunteers: yes
Observational model: COHORT
Time perspective: PROSPECTIVE
Sampling method: NON_PROBABILITY_SAMPLE
Study population: Adult healthy volunteers

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.

Detailed description: Elevated intracranial pressure (ICP) is a common and potentially life threatening condition arising from a variety of pathological conditions including traumatic brain injury (TBI), intracranial hemorrhage, subarachnoid hemorrhage and brain tumors. 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.

Eligibility criteria: Inclusion Criteria:

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

Exclusion Criteria:

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

Primary outcomes:
measure: Changes in ONSD in mm With Changes in ICP in Healthy Volunteers.
timeFrame: 1 day
Secondary outcomes:
Other outcomes:
Locations:
city: Toronto
country: Canada
facility: Toronto Western Hospital
state: Ontario
Study officials:
affiliation: Assistant Professor, Toronto Western Hospital, University Health Network
name: Lashmi Venkatraghavan, MD
role: PRINCIPAL_INVESTIGATOR
References: