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Effectiveness of Two Different Body Positions During Facemask Ventilation in Obese Patients

Not Applicable
Not yet recruiting
Conditions
Obesity
Interventions
Other: Head position for face mask ventilation during induction head elevated
Other: Head position for face mask ventilation during induction supine
Registration Number
NCT06305273
Lead Sponsor
Mount Sinai Hospital, Canada
Brief Summary

It is important to provide enough oxygen to the patients who are asleep during surgery. One way to do this is by using a mask placed over the face to help them breathe. When it becomes difficult getting enough oxygen into the patient's body using the mask, it's called difficult mask ventilation. There can be different reasons for this, and having a higher BMI is one of them. Body physique is assessed by Body Mass Index (BMI). This calculation gives an indication of a person's weight relative to their height.

There is some evidence in the research literature to suggest that when the patient is positioned in a way that helps their airway, like using a device to lift their head and torso 25 degrees , it might help the process of getting enough oxygen work better. The study aims to determine if patients with high BMI can breathe better using a face mask while they are in a head elevated position compared to lying flat on their back.

Detailed Description

Facemask ventilation is an important technique applied by anesthesiologists after induction of general anesthesia and before tracheal intubation. It is also used as a rescue maneuver in situations where a patient's consciousness is compromised affecting oxygenation. Obesity is well known to be one of the difficult predictors for facemask ventilation. In fact, the occurrence of difficult facemask ventilation is more frequent in obese patients than non obese. One of the maneuvers described to optimize the effectiveness of facemask ventilation in the general population is positioning the patient in a 25 degree head elevated position. A previous study has demonstrated improvement in facemask ventilation in obese patients with BMI from 30 to 40 kg/m2 in the head elevated position, compared to supine. However, it is not yet determined if this is applicable to patients with a BMI above 40 kg/m2. Adult obese patients with BMI of at least 40 kg/m2 will be randomized to be ventilated after induction of general anesthesia via a face mask while in one of the positions: supine or head elevated, while the volume of air that enters and exits the lungs is measured. Participants will then be changed to the second position, ventilated in the same manner and measures obtained again.

Do patients with class 3 obesity positioned in the head elevated position can be better ventilated with a face mask and positive pressure, compared to the supine position?

Recruitment & Eligibility

Status
NOT_YET_RECRUITING
Sex
All
Target Recruitment
38
Inclusion Criteria
  • BMI > 40 kg/m2
  • age > 18 years
  • scheduled for elective surgery under general anesthesia
  • have the ability to comprehend the rationale for the study and provide consent
Exclusion Criteria
  • pregnancy,
  • risk of aspiration of gastric content
  • patients using glucagon-like peptide(GLP)-1 agonists
  • emergency cases
  • upper airway disease or airway anatomical abnormalities
  • presence of major cardiovascular, respiratory, or cerebral vascular disease
  • if the provider anesthesiologist indicates an awake technique to secure the airway

Study & Design

Study Type
INTERVENTIONAL
Study Design
CROSSOVER
Arm && Interventions
GroupInterventionDescription
Head elevatedHead position for face mask ventilation during induction head elevatedParticipant will be ventilated with facemask while in head elevated position.
SupineHead position for face mask ventilation during induction supineParticipant will be ventilated with facemask while in supine position.
Primary Outcome Measures
NameTimeMethod
Average tidal volumeDuring induction.

The primary outcome for this trial is the average tidal volume in 10 ventilations in each position, flat or head elevated.

Secondary Outcome Measures
NameTimeMethod
Predictors for difficult mask ventilation like BMIDuring induction

Secondary outcome will be: the incidence and correlation of other predictors for difficult mask ventilation like BMI.

Predictors for difficult mask ventilation like severely limited mandibular protrusionDuring induction

Secondary outcomes will be: the incidence and correlation of other predictors for difficult mask ventilation like severely limited mandibular protrusion.

Oropharyngeal airwayDuring induction

Incidence of use of an oropharyngeal airway during the protocol.

Predictors for difficult mask ventilation like presence of beardDuring induction

Secondary outcomes will be: the incidence and correlation of other predictors for difficult mask ventilation like, presence of a beard.

Predictors for difficult mask ventilation like history of snoring.During induction

Secondary outcomes will be: the incidence and correlation of other predictors for difficult mask ventilation like history of snoring.

Insufficient mask ventilationDuring induction.

Incidence of insufficient mask ventilation (defined as tidal volume (Vt) \< 4 ml/kg IBW), or failed facemask ventilation defined as absence of End-tidal carbon dioxide(EtCO2) after 3 consecutive ventilations.

Predictors for difficult mask ventilation like age of 57 yo or older.During induction

Secondary outcomes will be: the incidence and correlation of other predictors for difficult mask ventilation like, age of 57 yo or older.

Predictors for difficult mask ventilation like Mallampati classification III or IVDuring induction

Secondary outcomes will be: the incidence and correlation of other predictors for difficult mask ventilation like Mallampati classification III or IV.

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