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A Novel Method of Preoxygenation Using a Bain Circuit

The recruitment status of this study is unknown. The completion date has passed and the status has not been verified in more than two years.
Verified August 2009 by National Health Service, United Kingdom.
Recruitment status was:  Recruiting
Information provided by:
National Health Service, United Kingdom Identifier:
First received: August 12, 2009
Last updated: NA
Last verified: August 2009
History: No changes posted

The purpose of this study is to determine whether rebreathing for a short time (a bit like breathing into a paper bag) will stimulate faster breathing and thus make the giving of Oxygen more effective.

The hypothesis is that the investigators method (rebreathing) will be faster than the current method of administering Oxygen.

Condition Intervention Phase
Healthy Volunteers
Drug: Oxygen
Phase 4

Study Type: Interventional
Study Design: Allocation: Randomized
Intervention Model: Crossover Assignment
Masking: Double Blind (Participant, Outcomes Assessor)
Primary Purpose: Supportive Care
Official Title: A Novel Method of Preoxygenation Using Partial Rebreathing Via a Coaxial Mapleson D Breathing System (Bain Circuit)

Resource links provided by NLM:

Further study details as provided by National Health Service, United Kingdom:

Primary Outcome Measures:
  • Time to end-tidal oxygen of 90% [ Time Frame: 5 minutes ]

Secondary Outcome Measures:
  • Level of discomfort as assessed by questionnaire [ Time Frame: 5 minutes ]

Estimated Enrollment: 40
Study Start Date: August 2009
Estimated Study Completion Date: June 2010
Estimated Primary Completion Date: June 2010 (Final data collection date for primary outcome measure)
Arms Assigned Interventions
Experimental: Rebreathing method of preoxygenation
Subjects will breathe Oxygen through a close fitting mask, but the flow will be low so that they rebreathe some of their expired air. After 30 seconds, the flow will be turned up so that they will breathe 100% Oxygen.
Drug: Oxygen
Experimental: Low flow Oxygen for 30 seconds then high flow for 3.5 minutes. Active comparator: High flow Oxygen for 4 minutes.
Active Comparator: T method of preoxygenation
Tidal breathing of 100% oxygen through a well fitting facemask, for 4 minutes.
Drug: Oxygen
Experimental: Low flow Oxygen for 30 seconds then high flow for 3.5 minutes. Active comparator: High flow Oxygen for 4 minutes.

Detailed Description:

It is standard practice for patients to breathe oxygen before receiving a general anaesthetic. This is called preoxygenation. It is done by using a mask which fits snugly onto the face. But for how long should patients breathe oxygen? Is taking deep breaths a good idea? What is the best oxygen flow rate? These questions are important because preoxygenation is one of the things which makes anaesthesia safe, so finding the best way of doing it might help save lives. Previous research has attempted to identify the best way to give oxygen before anaesthesia. It seems that breathing pure oxygen for three minutes is enough, or if you are in an urgent situation, then taking deep breaths of pure oxygen for a minute will do. However, there is another possible way of doing it which has not yet been looked at.

Asking someone to breathe back in the air they have just exhaled seems, on the face of it, to be pointless at best. But doing just that for a very short time will make the person breathe harder. Then when you give them pure oxygen, they will breathe it in really deeply and this might make the preoxygenation quicker. That's the theory. To test it we plan to ask 40 healthy people to do the standard preoxygenation, then try our new way. We won't be giving anaesthetic, just the oxygen.

The hypothesis is that our new method will be quicker than the existing one.


Ages Eligible for Study:   18 Years to 40 Years   (Adult)
Sexes Eligible for Study:   Male
Accepts Healthy Volunteers:   Yes

Inclusion Criteria:

  • BMI 18-27
  • Non-smoker
  • No chronic cardiorespiratory or neuromuscular illness
  • No intercurrent illness

Exclusion Criteria:

  • Unable/unwilling to consent
  Contacts and Locations
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Please refer to this study by its identifier: NCT00958178

Contact: John Glen, MBChB; BSc +44(0)1414231465
Contact: Richard Price, MBChB +44(0)7872957716

United Kingdom
Victoria Infirmary Recruiting
Glasgow, United Kingdom, G42 9LF
Contact: John Glen, MBChB; BSc    +44(0)1414231465   
Principal Investigator: John Glen, MBChB         
Sponsors and Collaborators
National Health Service, United Kingdom
Principal Investigator: John Glen, MBChB UK National Health Service
  More Information

Responsible Party: John Glen, National Health Service Identifier: NCT00958178     History of Changes
Other Study ID Numbers: 08/S071038
Study First Received: August 12, 2009
Last Updated: August 12, 2009 processed this record on April 27, 2017