Intracranial Pressure in Experimental Models of Headache

The purpose of this study is to determine whether increased pressure in the head is elevated in people who suffer from High Altitude Headache. We hypothesise that head pressure will be elevated in people with High Altitude Headache.

Study Overview

• Status: Completed
• Conditions: High Altitude Headache
• Intervention / Treatment: Drug: Acetazolamide; Drug: Lactose monohydrate

Detailed Description

High Altitude Headache is the primary symptom of Acute Mountain Sickness. However, at present the reason why some individuals suffer from High Altitude Headache and others do not remains unknown. It is widely believed that elevated pressure within the brain leads to stretching of pain sensitive fibres and thus headache. However, evidence of raised intracranial pressure during High Altitude Headache is currently unavailable. Therefore, this study aims to examine a proxy measure of intracranial pressure (Optic Nerve Sheath Diameter) in persons visiting High Altitude, half of whom have been given the drug acetazolamide that is known to reduce headache symptoms.

• Study Type: Interventional
• Enrollment (Actual): 23
• Phase: Not Applicable

Contacts and Locations

Study Locations

• United Kingdom
  • Gwynedd
    • Bangor, Gwynedd, United Kingdom, LL57 2PZ
      • School of Sport, Health and Exercise Sciences, Bangor University

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: 18 years and older (Adult, Older Adult)
• Accepts Healthy Volunteers: Yes
• Genders Eligible for Study: All

Description

Inclusion Criteria:

• Member of the Italian High Altitude Research Expeditions

Exclusion Criteria:

• Are under the age of 18years;
• sulfonamide allergy
• Liver or kidney disfunction
• Have any other uncontrolled medical condition
• Or are unable to give consent.

Study Plan

How is the study designed?

Design Details

• Primary Purpose: Basic Science
• Allocation: Randomized
• Interventional Model: Parallel Assignment
• Masking: Quadruple

Number of Arms

2

Arms and Interventions

Participant Group / Arm	Intervention / Treatment
Experimental: Acetazolamide; Arm 1: ACETAZOLAMIDE (250mg) will be given to subjects at fifteen, twenty and thirty two hours post hypoxic exposure (3777m).	Drug: Acetazolamide; During a forty eight hour hypoxic exposure (3777m), subjects will be given either acetazolamide or placebo at hours fifteen, twenty and thirty two.; Other Names: Diamox
Placebo Comparator: Placebo; Placebo (LACTOSE MONOHYDRATE) will be given to subjects at fifteen, twenty and thirty two hours post hypoxic exposure (3777m).	Drug: Lactose monohydrate; During a forty eight hour hypoxic exposure (3777m), subjects will be given either acetazolamide or placebo at hours fifteen, twenty and thirty two.

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Change in Optic Nerve Sheath Diameter by Ultrasonography	Baseline is defined as the average of the 3 hour and 12 hour normoxia measurement. 24 hours is defined at the 24 hour hypoxia measurement. Optic nerve sheath diameter obtained by ultrasonography of the eye. Increased optic nerve sheath diameter suggests greater intra cranial pressure.	Optic Nerve Sheath Diameter: baseline, 24 hours.

Secondary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Change in High Altitude Headache by Visual Analogue Scale	Baseline is defined as the average of the 3 hour and 12 hour normoxia measurement. 24 hours is defined at the 24 hour hypoxia measurement. Outcome measured using visual analogue scale, where 0 mm is no headache and 100 mm is maximum headache.	High Altitude Headache: baseline, 24 hours.
Change in Blood Oxygen Saturation	Baseline is defined as the average of the 3 hour and 12 hour normoxia measurement. 24 hours is defined at the 24 hour hypoxia measurement.	Blood Oxygen Saturation: baseline, 24 hours.
Change in Fluid Balance	Baseline is defined as the average of the 3 hour and 12 hour normoxia measurement. 24 hours is defined at the 24 hour hypoxia measurement. Urine output was recorded by 24 hour urine collection and fluid intake by 24 hour food diaries. Fluid balance was calculated as: (urine output (L) / fluid intake (L) ) * 100.	Fluid Balance: baseline, 24 hours.
Change in Optic Nerve Sheath Diameter	Baseline is defined as the average of the 3 hour 12 hour normoxia measurements. 3 hours is defined at the 3 hour hypoxia measurement.	Optic Nerve Sheath Diameter: baseline, 3 hours.
Change in Optic Nerve Sheath Diameter	Baseline is defined as the average of the 3 hour 12 hour normoxia measurements. 12 hours is defined at the 12 hour hypoxia measurement.	Optic Nerve Sheath Diameter: baseline, 12 hours.
Change in Optic Nerve Sheath Diameter	Baseline is defined as the average of the 3 hour and 12 hour normoxia measurements. 36 hours is defined at the 36 hour hypoxia measurement.	Optic Nerve Sheath Diameter: baseline, 36 hours.

Collaborators and Investigators

• Sponsor: Bangor University
• Collaborators: Universita di Verona; North Wales Research Committee, UK
• Investigators: Principal Investigator: Justin S Lawley, BSc, Bangor University

Publications and helpful links

General Publications

• Lawley JS, Oliver SJ, Mullins P, Morris D, Junglee NA, Jelleyman C, Macdonald JH. Optic nerve sheath diameter is not related to high altitude headache: a randomized controlled trial. High Alt Med Biol. 2012 Sep;13(3):193-9. doi: 10.1089/ham.2012.1019.

Study record dates

Study Major Dates

• Study Start: July 1, 2011
• Primary Completion (Actual): August 1, 2011
• Study Completion (Actual): August 1, 2011

Study Registration Dates

• First Submitted: January 27, 2011
• First Submitted That Met QC Criteria: January 31, 2011
• First Posted (Estimate): February 2, 2011

Study Record Updates

• Last Update Posted (Estimate): February 7, 2012
• Last Update Submitted That Met QC Criteria: February 6, 2012
• Last Verified: December 1, 2011

More Information

Terms related to this study

• Keywords: High Altitude Headache; intra-cranial pressure; hypoxia
• Additional Relevant MeSH Terms: Pain; Neurologic Manifestations; Headache; Physiological Effects of Drugs; Molecular Mechanisms of Pharmacological Action; Enzyme Inhibitors; Carbonic Anhydrase Inhibitors; Natriuretic Agents; Diuretics; Anticonvulsants; Acetazolamide
• Other Study ID Numbers: F002686; 2010-019520-31 (EudraCT Number)