Endotracheal Tube Audible Leak Test

Endotracheal Tube Audible Leak Test: What is the Accuracy?

The endotracheal tube (ETT) leak test (LT), or audible leak test is a widely performed assessment to verify appropriate tube size in neonates, infants and children. However, many factors are known to influence the audible leak test. Even though the test is widely performed, the accuracy has not been evaluated.

Study Overview

• Status: Completed
• Conditions: Mechanical Ventilation Complication; Anesthesia Intubation Complication
• Intervention / Treatment: Other: Assess for Audible Endotracheal Leak; Other: Assess for Endotracheal Leak with direct visualization under rigid bronchoscope

Detailed Description

The endotracheal tube (ETT) leak test (LT), or audible leak when the peak airway pressures reach 15-30 cmH2O, is a commonly performed assessment to confirm that an endotracheal tube size is appropriate for a child in order to minimize the risk of airway injury and adverse events after removal of ETT. Many factors are known to affect the results of the leak test and variation in results among experienced anesthesiologists may be as great as 38%, but the accuracy of the audible leak test by directly observing the presence of a leak around the ETT has not been evaluated. This study will attempt to use direct visualization of the air leak to correlate to and assess the accuracy of the audible air leak test.

• Study Type: Observational
• Enrollment (Actual): 86

Contacts and Locations

Study Locations

• United States
  • Mississippi
    • Jackson, Mississippi, United States, 39216
      • University of Mississippi Medical Center

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: 1 month to 8 years (Child)
• Accepts Healthy Volunteers: No
• Genders Eligible for Study: All

• Sampling Method: Non-Probability Sample

Study Population

Children aged between 1 month (post-natal) and 8 years scheduled for ENT surgery requiring general anesthesia with an endotracheal tube.

Description

Inclusion Criteria:

• Children aged between 1 month (post-natal) and 8 years scheduled for ENT surgery requiring general anesthesia with an endotracheal tube.

Exclusion Criteria:

• Known history of subglottic stenosis
• Known history of recurrent croup
• Known history of endolaryngeal or subglottic lesions
• Parents refusal of participation in study

Study Plan

How is the study designed?

Design Details

• Observational Models: Cohort
• Time Perspectives: Prospective

Number of groups / cohorts

1

Cohorts and Interventions

Group / Cohort

Intervention / Treatment

Endotracheal Leak; Assess for Audible Endotracheal Leak; Assess for Endotracheal Leak with direct visualization under rigid bronchoscope

Other: Assess for Audible Endotracheal Leak; In supine position, the head will be positioned in neutral position. With fresh gas flow at 2-5L/min, and pop off valve in the anesthesia machine closed and pressure in the inspiratory circuit is slowly increased until an audible leak is heard at the mouth. That pressure will be recorded.; Other: Assess for Endotracheal Leak with direct visualization under rigid bronchoscope; In the same patient position, a flexible nasal laryngoscope will be inserted and positioned superior to the laryngeal inlet by the surgeon. With fresh gas flow at 2-5L/min, and pop off valve in the anesthesia machine closed, the pressure in the inspiratory circuit will be increased slowly until a leak around the TT will be visualized by inspecting the supraglottic area for bubbles or air movement around the TT. The peak pressure at which leak is observed physically will be recorded. This is the end of the study.

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Primary Objective Evidence of an audible endotracheal leak and/or direct visualized endotracheal leak	Evidence of an audible endotracheal leak and/or direct visualized endotracheal leak using a flexible nasal laryngoscope positioned superior to the laryngeal inlet.	one year.

Secondary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Secondary Objective Evidence suggesting a relationship between the presence of an audible leak and direct visualization for cuffed and uncuffed TT's	Evidence suggesting a relationship between the presence of an audible leak and direct visualization for cuffed and uncuffed TT's.	one year.

Collaborators and Investigators

• Sponsor: University of Mississippi Medical Center
• Investigators: Principal Investigator: Madhankumar Sathyamoorthy, MBBS, MS, Univeristy of Mississippi Medical Center

Publications and helpful links

General Publications

• Suominen P, Taivainen T, Tuominen N, Voipio V, Wirtavuori K, Hiller A, Korpela R, Karjalainen T, Meretoja O. Optimally fitted tracheal tubes decrease the probability of postextubation adverse events in children undergoing general anesthesia. Paediatr Anaesth. 2006 Jun;16(6):641-7. doi: 10.1111/j.1460-9592.2005.01832.x.
• Finholt DA, Henry DB, Raphaely RC. Factors affecting leak around tracheal tubes in children. Can Anaesth Soc J. 1985 Jul;32(4):326-9. doi: 10.1007/BF03011335.
• Schwartz RE, Stayer SA, Pasquariello CA. Tracheal tube leak test--is there inter-observer agreement? Can J Anaesth. 1993 Nov;40(11):1049-52. doi: 10.1007/BF03009476.

Study record dates

Study Major Dates

• Study Start (Actual): December 7, 2015
• Primary Completion (Actual): January 9, 2017
• Study Completion (Actual): February 21, 2017

Study Registration Dates

• First Submitted: May 28, 2015
• First Submitted That Met QC Criteria: June 2, 2015
• First Posted (Estimate): June 3, 2015

Study Record Updates

• Last Update Posted (Actual): July 2, 2017
• Last Update Submitted That Met QC Criteria: June 29, 2017
• Last Verified: June 1, 2017

More Information

Terms related to this study

• Keywords: ventilation; intubation; airway; airleak
• Other Study ID Numbers: 2015-0164