Middle finger length to determine paediatric endotracheal tube size
Research type
Research Study
Full title
A survey to determine if endotracheal tube size in paediatric patients at Great Ormond Street Hospital is related to middle finger length.
IRAS ID
230420
Contact name
Mark Thomas
Contact email
Sponsor organisation
Division of Research and Innovation, Great Ormond Street Hospital for Children NHS Foundation Trust
Duration of Study in the UK
1 years, 0 months, 0 days
Research summary
Most children undergoing surgery have a general anaesthetic that necessitates the insertion of an endotracheal tube (ETT) to allow ventilation of the lungs and maintainance of anaesthetic. Endotracheal tubes come in a variety of designs and sizes, based upon the internal diameter.
Age based formulae are most commonly used to estimate the correct size of ETT. However, these have been shown to have a significant error rate, requring up to 30% to ETTs to be exchanged in large studies. Studies of the airway using ultrasound and computed tomography have demonstrated wide variation in the dimensions of the airway and differences between actual dimensions and those historically proposed.
Selection of an ETT which is too big can lead to injury to the larynx, vocal cords and airway due to excessive pressure. Meanwhile, use of an ETT which is too small can lead to leaks that can interfere with ventilation during surgery, interfere with end tidal capnography and increase the risk of pulmonary aspiration, often requiring the anaesthetist to exchange the ETT for another size. Repeated placement of ETTs can increase the risk of injury to the lips, teeth, mouth and vocal cords.
Middle finger length is an easily measured variable that has been shown to improve the positioning of ETTs when applied to the length of the ETT. However, this measurement has not been studied in relation to the diameter (size) of the ETT.
This study aims to collect the middle finger length of children attending this institution to gain a measure of this population, compare it to the predicted ETT size based upon age and compare it to the actual ETT size used. We hope to formulate an equation to improve the accuracy of selection of appropriately sized ETTs. Middle finger length will be measured in millimetres using disposable paper measuring tapes.
REC name
London - Camberwell St Giles Research Ethics Committee
REC reference
17/LO/1578
Date of REC Opinion
12 Dec 2017
REC opinion
Further Information Favourable Opinion