Inspired Oxygen (FIO2), End-tidal Oxygen (ETO2), End-tidal Carbon Dioxide (ETCO2) and Respiratory Rate (RR) Will be Measured Every 30 Seconds Clinical Trial
Official title:
Comparison of the Classic Face Mask Versus NuMask for Preoxygenation
Currently used face mask has certain disadvantages; such as, not providing a complete seal in certain patients, causing hand fatigue after holding the mask in place for more than a few minutes, causing claustrophobia in an occasional patient, the need to hold the mask from head of the bed, and possible worsening of the trauma in patients with facial injuries, and the need to use different size masks in different patients. The NuMask overcomes all of these disadvantages and does benefit the patients.
The administration of oxygen before anesthetic induction and tracheal intubation
(preoxygenation) is a well-recognized technique designed to increase oxygen reserves and
thereby delay the onset of arterial oxygen desaturation during apnea. It is particularly
important if manual ventilation is not desirable prior to intubation (eg: rapid sequence
induction) or if difficulty with ventilation or intubation is anticipated or in patients with
oxygen transport limitations. Because the "cannot ventilate/cannot intubate" situation is an
unpredictable event, theoretically all patients should be maximally preoxygenated.
Fraction of inspired oxygen (FIO2) is one of the factors in achieving maximal preoxygenation.
A common reason for the failure to achieve an FIO2 close to 1.0 is a leak under the face
mask. Several factors may contribute to the leak. These are edentulous patients, patients
with sunken cheeks, bearded patients, the presence of nasogastric tubes, wrong size face
masks, improper use of head straps, and patients with large heads and faces where even the
large size mask may not fit properly.
Recently a new intraoral mask "NuMask" has become available for anesthetic induction. It is
placed under the lips and outside the gums of the patient mouth (similar to snorkel mouth
piece), thus providing a good seal in almost any patient. In addition to providing a good
seal, the NuMask has other advantages over the standard face mask. It has very small dead
space (18 cc : 110 cc), provides comfortable grip, ventilation can be provided from any
position and causes less facial trauma.
The efficacy of preoxygenation using the NuMask will be compared to the classic face mask in
approximately 30 healthy and consenting adult volunteers. All of the volunteers will be
randomly assigned into one of 2 groups. All volunteers will be tested for three (3) periods
of 5 minute intervals. Inspired oxygen (FIO2), end-tidal oxygen (ETO2), end-tidal carbon
dioxide (ETCO2) and respiratory rate (RR) will be tested. Analysis of the data may reveal
whether the NuMask is equal, superior, or inferior to the classic face mask in achieving
maximal preoxygenation.
Although the NuMask has been tested and used in various scenarios of airway management, its
efficacy in achieving maximal preoxygenation has not been studied
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