Effect of Body Positioning on Upper Airway Patency During Induction of Anesthesia in Obese Patients

January 15, 2017 updated by: Yandong Jiang, Massachusetts General Hospital
Upper airway obstruction (UAO) during induction of general anesthesia is a frequently occurring complication. The mechanism of UAO during anesthesia shares many similarities with the upper airway obstruction observed during obstructive sleep apnea (OSA). Obesity is major risk factors for OSA and obese patients have a higher prevalence of UAO during anesthesia. The change of body position improved upper airway stability during sleep in patients with OSA.We hypothesis that the 30˚ reverse trendelenburg body position maintain airway patency in obese patients during general anesthesia.

Study Overview

Status

Completed

Conditions

Intervention / Treatment

Detailed Description

This is a prospective, observational study. Fifteen subjects with BMI limited in the range of 30 kg/m2 to 50 kg/m2, between 18-65 years of age meeting ASA physical status classification I-III requiring general anesthesia for elective surgery will be recruited from the main operating room of the Massachusetts General Hospital. We will start the recruiting process at least 12 hours ahead of the surgery at a pre-admission test area.

The PI/Co-I who approaches a potential subject who has expressed interest will not be the anesthesiologist providing anesthesia care for the subjects. In addition the PI/Co-I approaching the patient will reinforce that she or he does not have to participate and that the decision not to participate will not affect their care at anytime.

The Principal Investigator or Co-Investigator will participate in the informed consent process in operative holding area. Subjects to be recruited will be given a thorough review of the informed consent, as well as the study purpose and procedures, and its risks, discomforts, and potential benefits. When the subject is comfortable with and knowledgeable about the protocol, he or she will sign the consent form in the presence of the investigator. Investigator will also sign the informed consent form. All subjects will be given ample time to read the consent form and consider participating in the trial. Any complaint or problems related to our recruitment plan will report in real time to the IRB.

Study Type

Observational

Enrollment (Actual)

13

Contacts and Locations

This section provides the contact details for those conducting the study, and information on where this study is being conducted.

Study Locations

    • Massachusetts
      • Boston, Massachusetts, United States, 02114
        • Massachusetts General Hospital

Participation Criteria

Researchers look for people who fit a certain description, called eligibility criteria. Some examples of these criteria are a person's general health condition or prior treatments.

Eligibility Criteria

Ages Eligible for Study

18 years to 65 years (Adult, Older Adult)

Accepts Healthy Volunteers

No

Genders Eligible for Study

All

Sampling Method

Probability Sample

Study Population

Fifteen patients with BMI limited in the range of 30 kg/ m2 to 50 kg/ m2, between 18-65 years of age meeting ASA physical status classification I-III requiring general anesthesia for elective surgery

Description

Inclusion Criteria:

BMI limited in the range of 30 kg/ m2 to 50 kg/ m2, 18-65 years of age ASA physical status classification I-III Requiring general anesthesia for elective surgery -

Exclusion Criteria:

  1. Patients with major cardiovascular disease, respiratory disease, cerebral vascular disease or American Society of Anesthesiologists physical status class IV or greater.
  2. Abnormal vital signs on the day of admission for surgery [heart rate (HR, >100 bpm or < 40 bpm), blood pressure (BP, >180/100 mmHg or < 90/60 mmHg), room air transcutaneous oxyhemoglobin saturation (SPO2) < 96%] that are not correctable with his or her routine medication or commonly used pre-operative medication.
  3. Having claustrophobia and not able to tolerate the mask.
  4. Any person with an anticipated difficult airway or those with a history of difficult airway who requires a fiberoptic intubation while awake.
  5. Gastric-esophageal reflex disease that is refractory to treatment or a full stomach.
  6. The subject has been in bed for more than 24 hours.
  7. Neurological symptoms associated with neck extension, a neurological deficit from a previous stroke or spinal cord injury, a recent stroke or transient ischemic attack (TIA) within 2 weeks.
  8. Pregnant women and women less than one month post-partum. Ruling out pregnancy will be conducted by careful history and physical examination as performed routinely prior to surgery. If the history is believed to be unreliable, the patient will be excluded unless a pregnancy test is performed and the result of the test is negative.
  9. Emergency cases and subjects who have not adhered to the ASA NPO (Nil Per Os) guidelines.

    -

Study Plan

This section provides details of the study plan, including how the study is designed and what the study is measuring.

How is the study designed?

Design Details

What is the study measuring?

Primary Outcome Measures

Outcome Measure
Measure Description
Time Frame
expired tidal volume
Time Frame: 5 minutes
The ventilation will continue for 1 min in flat position and then, operating table will be changed to 30˚ reverse trendelenburg position and the ventilation will continue for 1 min. Then, operating table will leveled and the ventilation will continue for 1 min.
5 minutes

Secondary Outcome Measures

Outcome Measure
Measure Description
Time Frame
Vte/Area under the Curve (AUC) of the pressure trace during mask ventilation
Time Frame: 5 minutes
The area under the airway pressure curve (AUC) defined as the area from the baseline pressure to the peak pressure during inspiration was calculated for evaluating pressure applied during inspiration.The AUC is a reflection of the change in mean airway pressure.
5 minutes

Collaborators and Investigators

This is where you will find people and organizations involved with this study.

Sponsor

Study record dates

These dates track the progress of study record and summary results submissions to ClinicalTrials.gov. Study records and reported results are reviewed by the National Library of Medicine (NLM) to make sure they meet specific quality control standards before being posted on the public website.

Study Major Dates

Study Start

April 1, 2013

Primary Completion (Actual)

January 1, 2014

Study Completion (Actual)

January 1, 2014

Study Registration Dates

First Submitted

March 12, 2013

First Submitted That Met QC Criteria

March 13, 2013

First Posted (Estimate)

March 14, 2013

Study Record Updates

Last Update Posted (Estimate)

January 18, 2017

Last Update Submitted That Met QC Criteria

January 15, 2017

Last Verified

January 1, 2017

More Information

Terms related to this study

Other Study ID Numbers

  • 2012p-002632

This information was retrieved directly from the website clinicaltrials.gov without any changes. If you have any requests to change, remove or update your study details, please contact register@clinicaltrials.gov. As soon as a change is implemented on clinicaltrials.gov, this will be updated automatically on our website as well.