Clinical trial NCT01064908: A New Oxygen Mask for Carotid Endarterectomy Under Local Anaesthesia
Official title: A Study To Determine The Effectiveness Of A New Oxygen Mask At Increasing Arterial Oxygen Content During Carotid Endarterectomy Under Local Anaesthesia
Study type: OBSERVATIONAL
Overall status: COMPLETED
Conditions: Stroke
TIA
Surgery
Anaesthesia
Carotid Stenosis
Keywords: Endarterectomy, Carotid
Carotid stenosis
Oxygen mask
Lead sponsor: Brighton and Sussex University Hospitals NHS Trust
Sponsor class: OTHER
First posted: 2010-02-09
Enrollment: 25
Sex: ALL
Minimum age (years): 16
Standard ages: CHILD
ADULT
OLDER_ADULT
Accepts healthy volunteers: no
Observational model: CASE_ONLY
Time perspective: CROSS_SECTIONAL
Sampling method: NON_PROBABILITY_SAMPLE
Study population: Vascular Surgical Outpatients, booked for CEA under local anaesthetic

Brief summary: The purpose of this study is to determine the effectiveness of oxygenation and patient-acceptability of a novel oxygen face mask in patients undergoing carotid endarterectomies (CEAs).

Detailed description: Carotid endarterectomy (CEA) is a procedure to remove plaques from a carotid artery (one of the two main arteries supplying blood to the brain). The procedure is effective at reducing the risk of subsequent stroke. To access the artery, an incision is made in the artery wall which means that the artery must be clamped in order to prevent blood loss. Consequently, the blood supply (and therefore oxygen supply) to the brain is reduced. To ensure that the patient has sufficient oxygen to avoid brain damage, this procedure is often carried out under local anaesthetic as this means the anaesthetist can talk to them during the operation; by this means they can determine the patient's conscious level and whether or not they need supplementary oxygen.

There are various ways to administer the supplementary oxygen. Most oxygen masks completely cover the mouth and nose which inevitably limits patient-doctor communication. Oxygen is therefore usually administered via nasal tubes. However, the actual level of oxygen taken in by the patient is very hard to measure, and at best is only 40%.

A novel mask with an open design. By creating a 'vortex' of oxygen it can deliver higher concentrations of oxygen to the patient without significantly interfering with doctor-patient communication and, at the same time, improving patient comfort.

We wish to test the efficacy of this mask during CEA and plan to do this by measuring the oxygen content of blood directly using blood samples; we also monitor markers of brain damage which may occur from lack of oxygen. Finally, we will survey the patients as to acceptability of the mask.

Eligibility criteria: Inclusion Criteria:

* Male or female
* Booked for carotid endarterectomy under local anaesthetic
* Competent to consent to inclusion

Exclusion Criteria:

* Patient refusal and inability to provide consent
* Patients who are unable to understand instruction or communicate effectively
* Aged below 16 years
* Decreased conscious level during the period of study

Primary outcomes:
measure: The primary aim of this study the aim is to determine the effectiveness of the vortex oxygen mask in increasing blood oxygen levels during CEA in the awake patient during carotid clamping.
timeFrame: 0 hours
Secondary outcomes:
measure: To determine whether or not increased cerebral oxygen levels are associated with reduced cerebral injury, as measured by biomarkers: neuron-specific enolase and S100B.
timeFrame: 2.5 hours.
measure: A further secondary outcome is to determine whether the mask is acceptable to patients, as recorded by a questionnaire.
timeFrame: Within 24 hours post-operatively
Other outcomes:
Locations:
city: Brighton
country: United Kingdom
facility: Royal Sussex County Hospital
state: East Sussex
Study officials:
affiliation: Brighton and Sussex University Hospitals NHS Trust
name: Mark Harper, MB BS
role: PRINCIPAL_INVESTIGATOR
References: