Determination of the Optimal Size of Oropharyngeal Airway; Correlation With External Body Measurements

Yonsei University149 enrolled

Overview

There are several studies that have measured various oropharyngeal airway space distances using radiological method. However, direct confirmation of optimal size of oropharyneal airways (OPAs) in individual using fiberoptic bronchoscope (FOB) is lacking as now. The purposes of this study were to directly determinate the proper size of OPA in individual by FOB via different sizes of OPA in adults under general anestheisia. Additionally, we examine the relationships among the size of OPA, straight length from the incisors to the tip of the epiglottis by laryngoscopy, patient height, and external facial measurements.

Study Type

INTERVENTIONAL

Allocation

Purpose

PREVENTION

Masking

SINGLE

Enrollment

149

Conditions

Ear,Nose and Throat Surgery

Interventions

The OPAs was used four different sizes as No. 8 (80 mm, green), 9 (90 mm, yellow), 10 (100 mm, red), and 11 (110 mm, orange) in regular sequence. The curvilinear distance from the incisors to the tip of the epiglottis was measured by FOB (Olympus LF-GP; Olympus Optical Co., Tokyo, Japan) with tape marking via each size of OPAs. The distance from the distal end of OPA to the tip of the epiglottis was calculated by the difference between measured distance from the incisors to the tip of the epiglottis via each OPA by FOB and typical distance from the flange to distal end of each OPA via inside tube of OPA. When the size of OPAs was longer than distance from the incisors to the tip of the epiglottis, OPAs were partly withdrawn and repositioned the distal end of OPAs is placed just above the tip of epiglottis. Then, the length from the incisors to the flange of OPAs was measured. .

Eligibility

Sex: ALLMin age: 20 YearsMax age: 70 Years

Medical Language ↔ Plain English

Inclusion Criteria: * ASA class I-II 2. 20-70 years adults Exclusion Criteria: * 1\. an abnormal airway anatomy in preoperative radiologic study. * 2\. cervical spine pathology, * 3\. a history of difficult intubation, * 4\. neurologic disease or cardiovascular disease, * 5\. obesity (body mass index ≥ 30 kg m-1), * 6\. dental problem

Outcomes

Primary Outcomes

Optimal size of OPA

Primary Outcome - 기술(Description) The distance from the distal end of OPA to the tip of the epiglottis was calculated by the difference between measured distance from the incisors to the tip of the epiglottis via each OPA by FOB and typical distance from the flange to distal end of each OPA via inside tube of OPA. When the size of OPAs was longer than distance from the incisors to the tip of the epiglottis, OPAs were partly withdrawn and repositioned the distal end of OPAs is placed just above the tip of epiglottis. Then, the length from the incisors to the flange of OPAs was measured. The optimal size of OPAs in individuals was defined that the distal end of OPA is placed the tip of epiglottis as close as possible without impingement on the epiglottis when the flange of OPA contact with the four central incisors.

Time frame: 1 min after each FOB measurement