Comparison of Weight-based Versus External Ear-size Based Technique for Selection of Laryngeal Mask Airway in Pediatric Surgical Patients.

June 25, 2024 updated by: Muhammad Qamarul Hoda, Aga Khan University
Laryngeal Mask Airway (LMA) is widely used in pediatric surgical patients. The manufacturer recommends the size of LMA to be used in children should be based on actual body weight but this method has several limitations. To overcome these concerns, various alternatives have been tried by different researchers, one of them is external ear size for LMA size selection. Investigators therefore would like to know whether the external ear size based method can be used for LMA size selection in pediatric surgical patients in Pakistan.

Study Overview

Status

Completed

Conditions

Intervention / Treatment

Detailed Description

OBJECTIVE:

to determine whether external ear-size is non-inferior to weight for LMA size selection in pediatric surgical patients.

INTRODUCTION:

The Laryngeal Mask Airway (LMA) is widely used in pediatric population. The manufacturer recommends the size of LMA to be used in children should be based on actual body weight. However, this method has several limitations, the range of weight for a particular size is very wide, it may not be appropriate for overweight or underweight children as it is based on actual body weight rather than ideal body weight, in emergency situations where weight of the patient is unknown the correlation between weight and size of LMA is impossible, and finally weight based recommendation may not be suitable as development of the child's oropharyngeal cavity is related to height and age rather than weight. All these factors may lead to inappropriate size selection, which may result in larger sized LMA causing trauma/injury to the airway and smaller ones causing obstruction or insufficient ventilation. To overcome these concerns various alternatives to weight based technique have been tried by different researchers in both adult and pediatric patients, one of them is external ear size. Literature revealed differences in external ear size dimensions in different ethnic population and the investigator's literature search failed to reveal any local data/study in Pakistani pediatric patients where external ear size was compared or used for size selection of the LMA. The investigators therefore would like to know whether the external ear size based method can be used for LMA size selection in pediatric surgical patients in Pakistan.

HYPOTHESIS:

External ear-size based technique is not inferior to weight based technique for LMA selection in pediatric population.

Study Type

Interventional

Enrollment (Actual)

136

Phase

  • Not Applicable

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

  • Pakistan
    • Sindh
      • Karachi, Sindh, Pakistan, 74800
        • Muhammad Asghar Ali

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

6 months to 18 years (Child, Adult)

Accepts Healthy Volunteers

Yes

Description

Inclusion Criteria:

  1. All children aged between 6 months to 18 years of age of either sex
  2. American Society of Anesthesiologist (ASA) Classification I-II
  3. Elective surgical procedures in whom an LMA will be indicated
  4. Procedure lasting up to 2hrs

Exclusion Criteria:

  1. Any external ear morphological abnormality
  2. Previous external ear surgeries
  3. Patient/Parent refusal
  4. Children with oropharyngeal lesion
  5. Any patient conditions (Gastroesophageal Re-flux Disease [GERD], hiatal hernia, incomplete NPO, bowel obstruction etc.) or procedures requiring rapid sequence induction and intubation
  6. History of Upper respiratory tract infection (URTI) within the last 2 weeks

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

  • Primary Purpose: Prevention
  • Allocation: Randomized
  • Interventional Model: Parallel Assignment
  • Masking: Triple

Arms and Interventions

Participant Group / Arm
Intervention / Treatment
No Intervention: Group A - Weight Based Method

Body Weight Based method: This is the conventional method for LMA size selection. The patient will be weighed and LMA size corresponding to their weight will be used as follows.

(LMA Size - 1 for up to 5 kg of body weight) (LMA Size - 1.5 for 5 to 10 kg of body weight) (LMA Size - 2 for 10 to 20 kg of body weight) (LMA Size - 2.5 for 20 to 30 kg of body weight) (LMA Size - 3 for 30 to 50 kg of body weight)
Experimental: Group B - Ear Size Based Method

Ear Size Based method: External ear size will be measured by using a paper ruler and will be recorded in cm as follows:

Vertical length: will be measured from the most dependent portion of the lobule to the furthest portion of the auricle.

Horizontal length (width): from the tragus to the furthest part of the helix horizontally.

Dimension(cm2): Vertical length (L) × Horizontal length (width-W )

Based on these ear measurements, nearest smaller LMA size will be selected.
Device: Ear Size Based Method (Ambu® AuraOnce™ Laryngeal Mask Airway)

The Laryngeal Mask Airway (LMA) is one of the devices used to maintain airway during general anesthesia. Its appropriate size is selected according to patients body weight as recommended by the manufacturer.

However its appropriate size can also be selected via several other methods and one of them is patients external ear size. In this study the investigators will compare external ear size based method for LMA selection with the standard weight based method for LMA size selection.

Vertical Ear length: will be measured from the most dependent portion of the lobule to the furthest portion of the auricle.

Horizontal Ear length (width): from the tragus to the furthest part of the helix horizontally.

Dimension(cm2): Vertical length (L) × Horizontal length (width-W)

LMA Size LMA Cuff Length (cm) corresponding to vertical ear length.

LMA Cuff Width (cm) corresponding to horizontal ear width.

What is the study measuring?

Primary Outcome Measures

Outcome Measure
Measure Description
Time Frame
Proper Placement
Time Frame: 1 minute
Proper LMA placement will be assessed by chest expansion on positive pressure ventilation, absence of audible leak and a square wave capnograph waveform.
1 minute
Adequacy of Ventilation
Time Frame: 1 minute
Adequacy of ventilation: will be judged by an oxygen saturation of greater than or equal to 95% at a Fractional Inspired Oxygen concentration (FiO2) less than 0.5 and an end-tidal carbon dioxide (ETCO2) of 35-45 mmHg at a tidal volume of 6- 8 ml/kg Actual Body Weight (ABW) at peak airway pressure less than the oropharyngeal leak pressure (OLP), and by adjusting the respiratory rate (RR).
1 minute

Secondary Outcome Measures

Outcome Measure
Measure Description
Time Frame
Oropharyngeal Leak Pressure (OLP)
Time Frame: 30 seconds
Oropharyngeal Leak Pressure (OLP): will be determined at LMA intra-cuff pressure of 60 cmH2O by closing the Adjustable Pressure Limiting (APL) valve of the circle system at a fixed gas flow of 3 Liters per minute and by noting the circuit pressure at which an equilibrium will be reached and then releasing it completely.
30 seconds
Leak fraction (LF)
Time Frame: 1 minute
Leak fraction (LF): will be determined by comparing the difference between inspired and expired tidal volumes and dividing them by the inspired tidal volume at a tidal volume (TV) of 8 ml/kg actual body weight (ABW) with an I:E ratio of 1:2 and respiratory rate (RR) of 20 breaths per minute.
1 minute
Incidence of mucosal injury and laryngospasm
Time Frame: 1 minute

Incidence of mucosal injury in the two groups will be assessed by trauma or minor injury to the airway seen as blood on the device after removal.

Incidence of laryngospasm will also be noted.
1 minute

Collaborators and Investigators

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

Sponsor

Aga Khan University

Investigators

  • Principal Investigator: Muhammad Qamarul Hoda, FCAI, The Aga Khan University Hospital, Karachi, Pakistan.
  • Principal Investigator: Muhammad Asghar Ali, FCPS, The Aga Khan University Hospital, Karachi, Pakistan.
  • Principal Investigator: Hameed Ullah, FCPS, The Aga Khan University Hospital, Karachi, Pakistan.
  • Principal Investigator: Samie Asghar Dogar, FCPS, The Aga Khan University Hospital, Karachi, Pakistan.
  • Principal Investigator: Muhammad Saad Yousuf, FCPS, The Aga Khan University Hospital, Karachi, Pakistan.
  • Principal Investigator: Bushra Salim, FCPS, The Aga Khan University Hospital, Karachi, Pakistan.

Publications and helpful links

The person responsible for entering information about the study voluntarily provides these publications. These may be about anything related to the study.

General Publications

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 (Actual)

December 11, 2019

Primary Completion (Actual)

May 1, 2024

Study Completion (Actual)

June 15, 2024

Study Registration Dates

First Submitted

April 20, 2019

First Submitted That Met QC Criteria

April 29, 2019

First Posted (Actual)

April 30, 2019

Study Record Updates

Last Update Posted (Actual)

June 26, 2024

Last Update Submitted That Met QC Criteria

June 25, 2024

Last Verified

June 1, 2024

More Information

Terms related to this study

Keywords

Other Study ID Numbers

  • 2019-0246-3299

Plan for Individual participant data (IPD)

Plan to Share Individual Participant Data (IPD)?

YES

IPD Plan Description

The investigators will not publish any identifiable data, it will remain confidential. However the investigators will present this study in local and international meetings and also publish it in local or international journal.

IPD Sharing Time Frame

The data would be handled by the primary investigator and hard copies of the data will be saved by a lock and key method and soft copies will be saved on a computer and the data will be password protected. It will become available 6 months after completion of the study. Due to a regulatory requirement, this data will be saved for 15 years.

IPD Sharing Supporting Information Type

  • CSR

Drug and device information, study documents

Studies a U.S. FDA-regulated drug product

No

Studies a U.S. FDA-regulated device product

No

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.

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