Clinical trial NCT04410289: Defining the 'Sniffing Position" in Infants and Toddlers - A Pilot Study
Official title: A Prospective Randomized Pilot Study to Define and Validate the Standard 'Sniffing Position' in Infants and Toddlers.
Study type: INTERVENTIONAL
Overall status: COMPLETED
Phase: NA
Conditions: Airway Management
Infant ALL
Children, Only
Endotracheal Intubation
Keywords: pediatric intubation
direct laryngoscopy
sniffing position
external auditory meatus
pediatric anesthesia
pediatric airway management
Lead sponsor: Tufts Medical Center
Sponsor class: OTHER
First posted: 2020-06-01
Enrollment: 40
Sex: ALL
Minimum age (years): 1
Maximum age (years): 48
Standard ages: CHILD
Accepts healthy volunteers: no
Allocation: RANDOMIZED
Intervention model: SINGLE_GROUP
Primary purpose: OTHER

Brief summary: The "sniffing position" is widely accepted as a favorable position for direct laryngoscopy (DL) in both pediatric and adult patients. External anatomical markers are well documented to confirm proper 'sniffing position' in adults, but data on their use in the pediatric population is sparse. The investigators propose to define these markers in young children and investigate whether patients positioned using this standardized approach have better intubating conditions than those positioned randomly per the preference of the anesthesiologist.

Detailed description: The procedure of endotracheal intubation in adults and children is a continuum, and begins with proper head positioning prior to direct laryngoscopy (DL). It is an accepted paradigm that proper positioning optimizes intubating conditions, and decreases subsequent airway maneuvers and manipulation.

The sniffing position is an accepted airway positioning concept in pediatric airway management, and continues to be recommended by experts and textbooks in the field. Anatomical peculiarities such as the large head relative to the torso in infants and toddlers is assumed to put the head in proper position when gently extended. However, reproducible parameters to confirm optimal head positioning remain vague and unclear. In the absence of objective and measurable markers, practitioners position infants and toddlers according to their individual preferences, and as such the procedure lacks definition and objective clarity.

The investigators plan to recruit 40 healthy patients between the ages of 1 month - 48 months and randomize them to be positioned either according to a predetermined algorithm or positioned freely according to the provider's preference. Patients randomized to the intervention group will be positioned with the aim to horizontally align the external auditory meatus (EAM) with the sternal notch (SN).

In summary, the study aims to define the sniffing position for infants and toddlers using reproducible objective secondary markers, and investigate whether a systematic approach to positioning using such markers improves direct laryngoscopic outcomes in the young pediatric patient population.

Eligibility criteria: Inclusion Criteria:

* healthy infants and toddlers undergoing non-emergent surgery under general anesthesia with an oral endotracheal tube

Exclusion Criteria:

* neonates (infants under 1 month of age), infants and toddlers with congenital syndromes affecting the airway, and patients undergoing emergency surgery.

Primary outcomes:
measure: Difference in Intubation Difficulty Scale (IDS) Score
timeFrame: The brief time involved (5-10 minutes) involving the process of head positioning, direct laryngoscopy and endotracheal intubation.
Secondary outcomes:
measure: Angles of Deviation of the EAM-SN plane and Chin-Sinciput Plane from the Horizontal
timeFrame: Post-hoc analysis using a computer program to calculate angles. 10 minutes per patient.
Other outcomes:
Locations:
city: Boston
country: United States
facility: Tufts Medical Center
state: Massachusetts
Study officials:
affiliation: Tufts Medical Center
name: Aman Kalra, MD
role: PRINCIPAL_INVESTIGATOR
References:
citation: Akihisa Y, Hoshijima H, Maruyama K, Koyama Y, Andoh T. Effects of sniffing position for tracheal intubation: a meta-analysis of randomized controlled trials. Am J Emerg Med. 2015 Nov;33(11):1606-11. doi: 10.1016/j.ajem.2015.06.049. Epub 2015 Jun 23.
citation: El-Orbany M, Woehlck H, Salem MR. Head and neck position for direct laryngoscopy. Anesth Analg. 2011 Jul;113(1):103-9. doi: 10.1213/ANE.0b013e31821c7e9c. Epub 2011 May 19.
citation: Greenland KB, Eley V, Edwards MJ, Allen P, Irwin MG. The origins of the sniffing position and the Three Axes Alignment Theory for direct laryngoscopy. Anaesth Intensive Care. 2008 Jul;36 Suppl 1:23-7. doi: 10.1177/0310057X0803601s05.
citation: Greenland KB, Edwards MJ, Hutton NJ. External auditory meatus-sternal notch relationship in adults in the sniffing position: a magnetic resonance imaging study. Br J Anaesth. 2010 Feb;104(2):268-9. doi: 10.1093/bja/aep390. No abstract available.
citation: Prakash S, Rapsang AG, Mahajan S, Bhattacharjee S, Singh R, Gogia AR. Comparative evaluation of the sniffing position with simple head extension for laryngoscopic view and intubation difficulty in adults undergoing elective surgery. Anesthesiol Res Pract. 2011;2011:297913. doi: 10.1155/2011/297913. Epub 2011 Oct 29.
citation: Collins JS, Lemmens HJ, Brodsky JB, Brock-Utne JG, Levitan RM. Laryngoscopy and morbid obesity: a comparison of the "sniff" and "ramped" positions. Obes Surg. 2004 Oct;14(9):1171-5. doi: 10.1381/0960892042386869.
citation: Horton WA, Fahy L, Charters P. Defining a standard intubating position using "angle finder". Br J Anaesth. 1989 Jan;62(1):6-12. doi: 10.1093/bja/62.1.6.
citation: Kim EH, Lee JH, Song IK, Kim JT, Kim BR, Kim HS. Effect of head position on laryngeal visualisation with the McGrath MAC videolaryngoscope in paediatric patients: A randomised controlled trial. Eur J Anaesthesiol. 2016 Jul;33(7):528-34. doi: 10.1097/EJA.0000000000000448.
citation: Vialet R, Nau A, Chaumoitre K, Martin C. Effects of head posture on the oral, pharyngeal and laryngeal axis alignment in infants and young children by magnetic resonance imaging. Paediatr Anaesth. 2008 Jun;18(6):525-31. doi: 10.1111/j.1460-9592.2008.02530.x. Epub 2008 Mar 18.
citation: Adnet F, Borron SW, Racine SX, Clemessy JL, Fournier JL, Plaisance P, Lapandry C. The intubation difficulty scale (IDS): proposal and evaluation of a new score characterizing the complexity of endotracheal intubation. Anesthesiology. 1997 Dec;87(6):1290-7. doi: 10.1097/00000542-199712000-00005.
citation: Greenland KB, Edwards MJ, Hutton NJ, Challis VJ, Irwin MG, Sleigh JW. Changes in airway configuration with different head and neck positions using magnetic resonance imaging of normal airways: a new concept with possible clinical applications. Br J Anaesth. 2010 Nov;105(5):683-90. doi: 10.1093/bja/aeq239. Epub 2010 Sep 15.