Effect of Head Rotation on Efficacy of Face Mask Ventilation in Anesthetized Obese (BMI ≥ 35) Adults

Not Applicable

Completed

Conditions: Noninvasive Ventilation

Interventions: Procedure: Head Rotation During Face Mask Ventilation
Device: Medline Top Valve Anesthesia Mask

Registration Number: NCT03876873

Lead Sponsor: University of Missouri-Columbia

Brief Summary: Mask ventilation is fundamental to airway management at the start of surgical procedures requiring general anesthesia. For general anesthesia, medications are provided that affect the entire body and lead to a loss of consciousness. Medical professionals perform mask ventilation by placing a plastic mask over a subjects mouth and nose to provide enough oxygen for the placement of a breathing tube. In this study, we expect that a 45 degree rotation of the head will increase the efficiency of mask ventilation.

Detailed Description: Mask ventilation is a foundation of airway management after the initial induction of anesthesia. It allows for adequate oxygenation of the patient to buy enough time for intubation, during which the patient is not ventilated. However, in some patients mask ventilation may be difficult - older than 55 years, heavier (BMI \> 26 kg/m\^2), with no teeth, having a beard or sleep apnea. Inadequate ventilation, if not corrected, can result in decreasing oxygen saturation to dangerous levels - which could lead to devastating complications. As a result, the efficacy of mask ventilation is of critical importance to patient safety after the induction of anesthesia.

A recent study proposed that mask ventilation could be improved simply by turning a patient's head. The study showed that rotating a patient's head to a 45 degree angle significantly improved mask ventilation when compared with the head placed in a neutral position. However, this study was done in patients with a BMI lass than 35. As such, the effects of head rotation on the efficacy of mask ventilation has not been studied in patients with a BMI of 35 and greater.

Obesity (BMI ≥ 30 kg/m\^2) affects almost 40% of US adults and is one of the most prevalent health concerns in our society. It is a predictor of difficult mask ventilation because it is associated with increased upper airway obstruction, decreased airway patency, and decreased lung volumes such as functional residual capacity (FRC). If previous findings in regard to the effects of 45 degree head rotation on the efficacy of ventilation hold true in the obese patient, then this study will show that head rotation could be used as a simple way to improve the efficacy of mask ventilation for patients with a BMI of 35 and above.

Recruitment & Eligibility

Status: COMPLETED

Sex: All

Target Recruitment: 21

Inclusion Criteria

Age ≥ 18 years
ASA Physical Status Classification I-III
Body Mass Index (BMI) ≥ 35 kg/m^2

Exclusion Criteria

Inability to obtain written informed consent
Pregnant or breastfeeding
Limited head rotation or neck extension
Subjects with expected or history difficult intubation
Large beard
Orogastric (OG)/nasogastric (NG) tube
Gastroesophageal Reflux Disease (GERD)

Study & Design

Study Type: INTERVENTIONAL

Study Design: CROSSOVER

Arm && Interventions

Group	Intervention	Description
Group A	Medline Top Valve Anesthesia Mask	Head Rotation During Face Mask Ventilation. Step 1: Neutral Position (1 minute), Step 2: Head Rotation (1 minute), Step 3: Neutral Position (1 minute)
Group B	Head Rotation During Face Mask Ventilation	Head Rotation During Face Mask Ventilation. Step 1: Head Rotation (1 Minute), Step 2: Neutral Position (1 minute), Step 3, Head Rotation (1 Minute)
Group A	Head Rotation During Face Mask Ventilation	Head Rotation During Face Mask Ventilation. Step 1: Neutral Position (1 minute), Step 2: Head Rotation (1 minute), Step 3: Neutral Position (1 minute)
Group B	Medline Top Valve Anesthesia Mask	Head Rotation During Face Mask Ventilation. Step 1: Head Rotation (1 Minute), Step 2: Neutral Position (1 minute), Step 3, Head Rotation (1 Minute)

Primary Outcome Measures

Name	Time	Method
Maximal and Average Expiratory Tidal Volume During Mask Ventilation	Day 1	Measured in mL

Secondary Outcome Measures

Name	Time	Method
Maximal and Average Airway Flow During Mask Ventilation	Day 1	Measured in L/min
Maximal and Average Inspiratory Tidal Volume During Mask Ventilation	Day 1	Measured in mL
Maximal and Average End-tidal CO2 (ETCO2) During Mask Ventilation	Day 1	Measured in mm Hg
Lowest and Delta O2 Saturation Drop on SpO2 During Mask Ventilation	Day 1	Measured in % Delta O2 saturation drop is the difference between 100% oxygen saturation and the lowest oxygen saturation measured, e.g., 100 - 96 (lowest measured) = 4 (delta).
Lowest and Delta O2 Saturation Drop on SpO2 During Intubation	Day 1	Measured in % Delta O2 saturation drop is the difference between 100% oxygen saturation and the lowest oxygen saturation measured, e.g., 100 - 96 (lowest measured) = 4 (delta).