(1) The Cole formula for uncuffed tubes: ID (intenal diameter) in mm= (age in years)/4 + 4 (2) The Motoyama formula for cuffed ETTs in children aged 2 yr or older: ID in mm = (age in years)/4 + 3.5 (3) The Khine formula for cuffed ETTs in children younger than 2 yr: ID in mm = (age in years)/4 + 3.0

xlomafota13 shared this article with you from Inoreader Message: https://resus.me/kids-tracheal-tubes-formulas-galore/ An ultrasound study of paediatric airways showed sonographic measurement to be a better predictor of tracheal tube size (using a formula – derived and then validated – to estimate external tube diameter) than traditional formulae for selecting the internal tube diameter based on age. Since the measurements, taken at the lower edge of the cricoid cartilage, were made after patients were paralyzed, and were performed without ventilation or positive end-expiratory pressure to minimize fluctuation in tracheal diameter, taking about 30 seconds, this is not something I anticipate applying in critical care practice. However, the paper does provide a good opportunity to revise some of the existing formulae. They used: (1) The Cole formula for uncuffed tubes: ID (intenal diameter) in mm= (age in years)/4 + 4 (2) The Motoyama formula for cuffed ETTs in children aged 2 yr or older: ID in mm = (age in years)/4 + 3.5 (3) The Khine formula for cuffed ETTs in children younger than 2 yr: ID in mm = (age in years)/4 + 3.0 The formula established in the study was: cuffed ETT outer diameter (OD) = 0.46 x (subglottic diameter) + 1.56 uncuffed ETT OD = 0.55 x (subglottic diameter) + 1.16 Age in months also correlated with optimal ETT size in mm, although the correlation was weaker than for subglottic diameter: cuffed ETT OD = 0.027 x (age) + 5.2 uncuffed ETT OD = 0.030 x (age) + 5.4 BACKGROUND: Formulas based on age and height often fail to reliably predict the proper endotracheal tube (ETT) size in pediatric patients. We, thus, tested the hypothesis that subglottic diameter, as determined by ultrasonography, better predicts optimal ETT size than existing methods. METHODS: A total of 192 patients, aged 1 month to 6 yr, who were scheduled for surgery and undergoing general anesthesia were enrolled and divided into development and validation phases. In the development group, the optimal ETT size was selected according to standard age-based formulas for cuffed and uncuffed tubes. Tubes were replaced as necessary until a good clinical fit was obtained. Via ultrasonography, the subglottic upper airway diameter was determined before tracheal intubation. We constructed a regression equation between the subglottic upper airway diameter and the outer diameter of the ETT finally selected. In the validation group, ETT size was selected after ultrasonography using this regression equation. The primary outcome was the fraction of initial cuffed and uncuffed tube sizes, as selected through the regression formula, that proved clinically optimal. RESULTS: Subglottic upper airway diameter was highly correlated with outer ETT diameter deemed optimal on clinical grounds. The rate of agreement between the predicted ETT size based on ultrasonic measurement and the final ETT size selected clinically was 98% for cuffed ETTs and 96% for uncuffed ETTs. CONCLUSIONS: Measuring subglottic airway diameter with ultrasonography facilitates the selection of appropriately sized ETTs in pediatric patients. This selection method better predicted optimal outer ETT diameter than standard age- and height-based formulas. Prediction of Pediatric Endotracheal Tube Size by Ultrasonography Anesthesiology. 2010 Oct;113(4):819-24 AIRWAYANAESTHESIACRITICAL CAREPAEDIATRICULTRASOUND Post navigation PREVIOUS POST Two hands on the jaw for mask ventilation NEXT POST Fever in head injury might not be bad 3 THOUGHTS ON "KIDS TRACHEAL TUBES – FORMULAS GALORE" Christopher MARCH 30, 2011 AT 9:32 AM I think the question we have in the field is not tube size but rather cuff inflation volume! Easy for adults, 10 mL until the pilot balloon feels solid. For kids do we start with 5 mL? Less? Tube size based? All we have is a Broselow tape and cuffed tubes, no manometers to get the 20 cmH2O or less required to seal the airway. Are there any formulas for this? REPLY Cliff MARCH 30, 2011 AT 11:33 AM Good question! I think less – in fact less even for adults check out this table http://www.ncbi.nlm.nih.gov/pmc/articles/PMC535565/table/T3/ which comes from the article 'Endotracheal tube cuff pressure in three hospitals, and the volume required to produce an appropriate cuff pressure' at http://www.ncbi.nlm.nih.gov/pmc/articles/PMC535565/. I think for kids especially a manometer is a good idea Cliff REPLY Christopher MARCH 31, 2011 AT 10:35 AM Uh oh, field experience shows we fill the cuff with a full syringe! Likely we need to adjust our thinking and probably grab some more studies to get our protocols in order. Thank you for the link. REPLY LEAVE A REPLY Your email address will not be published. Required fields are marked * Comment Name * Email * Website Save my name, email, and website in this browser for the next time I comment. Just another WordPress site Search for: Search … RECENT POSTS How far can exponential spread of coronavirus go? Blow Them Away in Resus Humeral Intraosseous – Stay In & Stay Straight Analysing Difficult Resuscitation Cases – 2 Analysing Difficult Resuscitation Cases RECENT COMMENTS Cliff on Humeral Intraosseous – Stay In & Stay Straight Amy on Humeral Intraosseous – Stay In & Stay Straight Cliff on Humeral Intraosseous – Stay In & Stay Straight David williams on Humeral Intraosseous – Stay In & Stay Straight Cliff on Analysing Difficult Resuscitation Cases – 2 ARCHIVES April 2020 August 2019 October 2018 April 2018 March 2018 December 2017 September 2017 August 2017 June 2017 March 2017 February 2017 November 2016 October 2016 September 2016 August 2016 June 2016 May 2016 December 2015 November 2015 August 2015 July 2015 June 2015 May 2015 March 2015 January 2015 December 2014 November 2014 October 2014 September 2014 August 2014 July 2014 May 2014 April 2014 March 2014 February 2014 January 2014 December 2013 November 2013 October 2013 September 2013 August 2013 July 2013 June 2013 May 2013 April 2013 March 2013 February 2013 January 2013 December 2012 November 2012 October 2012 September 2012 August 2012 July 2012 June 2012 May 2012 April 2012 March 2012 February 2012 January 2012 December 2011 November 2011 October 2011 September 2011 August 2011 July 2011 June 2011 May 2011 April 2011 March 2011 February 2011 January 2011 December 2010 November 2010 October 2010 September 2010 August 2010 July 2010 June 2010 May 2010 April 2010 March 2010 February 2010 January 2010 December 2009 November 2009 October 2009 September 2009 June 2009 May 2009 April 2009 March 2009 February 2009 January 2009 December 2008 November 2008 October 2008 September 2008 CATEGORIES Acute Med All Updates Fascinomata Guidelines ICU Kids PHARM Podcasts Resus Trauma Ultrasound Uncategorized Video META Log in Entries RSS Comments RSS WordPress.org Proudly powered by WordPress Accuracy of Age-Based Formula to Predict the Size and Depth of Cuffed Oral Preformed Endotracheal Tubes in Children Undergoing Tonsillectomy. Via ear nose throat Related Articles Accuracy of Age-Based Formula to Predict the Size and Depth of Cuffed Oral Preformed Endotracheal Tubes in Children Undergoing Tonsillectomy. Ear Nose Throat J. 2021 Feb 09;:145561320980511 Authors: Tareerath M, Mangmeesri P Abstract OBJECTIVES: To retrospectively investigate the reliability of the age-based formula, year/4 + 3.5 mm in predicting size and year/2 + 12 cm in predicting insertion depth of preformed endotracheal tubes in children and correlate these data with the body mass index. PATIENTS AND METHODS: Patients were classified into 4 groups according to their nutritional status: thinness, normal weight, overweight, and obesity; we then retrospectively compared the actual size of endotracheal tube and insertion depth to the predicting age-based formula and to the respective bend-to-tip distance of the used preformed tubes. RESULTS: Altogether, 300 patients were included. The actual endotracheal tube size corresponded with the Motoyama formula (64.7%, 90% CI: 60.0-69.1), except for thin patients, where the calculated size was too large (0.5 mm). The insertion depth could be predicted within the range of the bend-to-tip distance and age-based formula in 85.0% (90% CI: 81.3-88.0) of patients. CONCLUSION: Prediction of the size of cuffed preformed endotracheal tubes using the formula of Motoyama was accurate in most patients, except in thin patients (body mass index < -2 SD). The insertion depth of the tubes was mostly in the range of the age-based-formula to the bend-to-tip distance. PMID: 33559493 [PubMed - as supplied by publisher] View on the web Inoreader. Take back control of your news feed. Follow us on Twitter and Facebook.