Use of cuffed tracheal tubes in neonates and infants: still a debate?
Francis Veyckemans MD, Jamie Peyton MD, Melissa Brooks Peterson MD
The use of cuffed tracheal tubes (TT) for children less than 8 years-old has dramatically changed anesthesia practice. The use of a cuff reduces the number of intubation attempts needed to obtain a tight seal during positive pressure ventilation and avoids the need to reintubate patients during surgery should a leak become problematic. They made capnography more reliable and allowed better monitoring of ventilation pressures and volumes. Cuffed tracheal tubes are now accepted as routine in pediatric anesthesia. Uncuffed tubes remain the only option for extremely premature neonates and are used regularly in the NICU and for children who weigh <3kg. However, the use of cuffed TTs in neonates and infants less than 3 kg remains controversial and is not recommended by their manufacturers even though large case series report their uneventful use. This topic has already been considered in a previous PAAD (https://ronlitman.substack.com/p/pediatric-airway-return-of-the-uncuffed?utm_source=publication-search) but two recent papers led us to reconsider it today.
Original Articles
Holzki J, Hoeve H, Tan H, Coté CJ, Rothschild M, Ponde V, Ustalar Ozgen ZS, Yamashita M. Unveiling myths of the paediatric larynx: a comprehensive review of anatomical publications and modern insights on cuffed endotracheal tubes. Malaysian Journal of Anaesthesiology 2024; 2:137-156 doi.org/10.35119/myja.v3i2.81.
Maguire S, Wade D, Curley J, Morris S. Design considerations for development of cuffed endotracheal tube for small airways. Paediatr Anaesth. 2025 Feb;35(2):91-98. doi: 10.1111/pan.15033. Epub 2024 Nov 19. PMID: 39560156.
The Holzki et al article is based on anatomic and in vitro data from P. Fayoux2 and M. Isa3 and on endoscopic explorations of damaged pediatric larynges.This review presents a strong indictment against the use of cuffed endotracheal tubes, especially the Microcuff™ ones, in neonates and small infants, concluding that : «Using cuffless endotracheal tubes until the end of the second year is rational and effective … rather than Microcuff™ tubes with oversized cuffs. »
At the same time, « Design considerations for development of cuffed endotracheal tube for small airways » was published in Pediatric Anesthesia by S. Maguire et al, who are R & D engineers at Medtronic®.
Let us consider some of the messages of the former publication in light of the worldwide clinical experience with cuffed TT in neonates and infants, and of the new cuff design proposals of Maguire et al.4 The authors start by making reference to Eckenhoff’s seminal 1951 scientific paper on the child’s larynx recommending the use of cuffless TT before 8 years of age.5 The anatomical basis of this paper has been confirmed : the larynx is funnel-shaped and the rigid circular cricoid ring is the narrowest part of the child’s upper airway. However, it is not the narrowest point of the airway at baselinein prematures and neonates. The posterior glottis has a width of 3 to 4mm in the infant, and this interarytenoid dimension (at the posterior glottis) at rest is approximately 60% to 80% of the cricoid cartilage internal diameter (ID). The other structures (arytenoids, supraglottis, vocal cords/glottis, and infraglottis) are all distensible. This is important because if an uncuffed endotracheal tube is sized to fit snugly along the cricoid ID it may result in increased pressure transmission and injury to glottic and supraglottic structures, particularly if the tracheal tube remains in the airway for a long period of time. The authors report the results of Isa’s study : using a 3 mm ID Microcuff™ TT as recommended by the manufacturer, they show that it cannot enter a tube of 4 mm ID used as a model for a neonate’s cricoid outlet because its OD at the deflated cuff level is 6.4 mm. The same experiment was repeated in fresh animal or infant larynges with similar results. This is surprising because small infants are intubated daily with the same equipment without applying force to the laryngeal structures and without immediate or late sequelae. This is confirmed by the decreased incidence of acute postoperative respiratory complications in a series of 5,247 children6 and a retrospective series of 297 PICU infants7: none of the patients initially intubated with a cuffed TT developed intubation-related damage while the 8 patients who needed major surgery for subglottic stenosis were ex-prematures initially intubated with an uncuffed TT. We cannot explain this discrepancy between experimental and clinical data, but some factors may be increased elasticity of tissues in vivo, effect of general anesthesia on surrounding structures, different angle of insertion of the TT in the glottis etc.
The second issue relates to the position of the cuff. To avoid compression of the cricoid mucosa, it should be positionned below the cricoid, in the tracheal lumen. The risk of intracricoid positioning of the cuff is a real concern and was already highlighted in Isa’s in vitro study with Microcuff™ TT 3 : it was observed in 77% of the cases and prompted a call for adapting the design of these TT, namely increasing the distance between the cranial part of the cuff and the vocal cords mark. This was not done and the same recommendation is therefore made by Maguire et al 4 : they propose using age-related calculated tracheal lengths from end of cricoid cartilage to carina and lengths of vocal cord to end of cricoid cartilage to determine a safe zone where a short, low-volume low-pressure cuff, should be placed as close as possible of the tip of the TT. This remind us that the risk of intracricoid or even intralaryngeal positioning of the cuff is a serious issue : it can be reduced by confirming its tracheal position by simultaneous palpation of the cuff in the neck and of its pilot balloon (although this is often difficult with low pressure cuffs), palpating the TT tip in the suprasternal notch or using ultrasound.8 Maguire et al also recommend modifying the size and shape of the cuff : it should be low-volume low-pressure, smaller and with a the tapered shape rather than the current barrel (cylindrical) one to reduce strain on the tracheal wall.4
The third issue concerns the folds in the deflated or partially inflated cuff. Despite being thinner and less deep in polyurethane made cuffs than in PVC ones, they are an obvious source of potential injury to the fragile surrounding mucosa. Does this mean that one should avoid using a cuffed TT with its cuff deflated or partially inflated, and change for a cuffed TT one size smaller or a cuffless TT if no leak appears around the TT when a pressure of 15-20 cmH2O is applied in the breathing circuit?
Hoski et all write : «Airway endoscopy is vital for detecting trauma, even after what seems like uneventful intubations.» This is obvious and studies with fiberoptic examination of the upper airway before intubation and immediately after extubation should be performed to close the debate. In the meantime, M Weiss and his group performed a rigid laryngotracheoscopy before intubation in 971 children out of whom 473 had been intubated before and mostly with a cuffed TT (9) : they found abnormal findings in about a quarter of the children in both groups but that glottic granulomas were more common in those who had been intubated before (3.6% vs 1.4%, p = 0.028).
Manufacturers of TT should take the recommendations of Maguire et al4 into account and adapt the design of the TT they produce accordingly. Moreover, even if the information is already available on the TTs, it is probably high time that the Societies of Anesthesiologists group together to suggest the manufacturers to classify the TTs according to their OD rather than the ID.
To conclude, we do not need to go back to cuffless TT in neonates and infants, but we should remember that laryngotracheal injury is more than a cuff issue. Tracheal intubation is an invasive procedure that should be performed carefully even in emergency circumstances. We should therefore 1) consider the OD of the TT at the level of the cuff, not its ID, when determining its initial size, 2) avoid using force to pass the laryngeal inlet and the cricoid area, 3) position the cuff below the cricoid, 4) remove the TT if there is no leak when the cuff is deflated as folds in the cuff could damage the mucosa, and 5) monitor cuff pressure which should be < 20 cmH2O in children..
Moreover, many other factors also increase the risk of laryngotracheal injury: light anesthesia and/or insufficient muscle relaxation, bucking or coughing at intubation or extubation, changes in head position, duration of intubation, sepsis, low cardiac output etc. It is also possible that the increasing use of video-enabled laryngoscopy systems may help clinicians judge the size of TT required more accurately, particularly when trainees are intubating. Instead of relying on being told that the tube looks like it is too large or small it becomes possible for everyone to see any size discrepancy at the laryngeal level for themselves and act accordingly.
What is your opinion ? Do you still use cuffless TT and for which patients ? Do you often observe an intracricoid position of the cuff? What is your strategy to prevent it? Please send your comment to Myron Yaster at myasterster@gmail.com.
References
1. Holzki J, Hoeve H, Tan H, Coté CJ, Rothschild M, Ponde V, Ustalar Ozgen ZS, Yamashita M. Unveiling myths of the paediatric larynx: a comprehensive review of anatomical publications and modern insights on cuffed endotracheal tubes. Malaysian Journal of Anaesthesiology 2024; 2:137-156 doi.org/10.35119/myja.v3i2.81.
2. Fayoux P, Devisme L, Merrot O, Marciniak B. Determination of endotracheal tube size in a perinatal population: an anatomical and experimental study. Anesthesiology 2006;104(5):954-960. doi: 10.1097/00000542-200605000-0001, PMID: 16645447.
3. Isa M, Holzki J, Hagemeier A, Rothschild MA, Coté CJ. Anatomical In vitro investigations of the pediatric larynx: a call for manufacturer redesign of tracheal tube cuff location and perhaps a call to reconsider the use of uncuffed tracheal tubes. Anesth Analg 2021;133(4):894-902. doi : 10.1213/ane.0000000000005565, PMID: 33901057.
4. Maguire S, Wade D, Curley J, Morris S. Design considerations for development of cuffed endotracheal tube for small airways. Paediatr Anaesth. 2025 Feb;35(2):91-98. doi: 10.1111/pan.15033. Epub 2024 Nov 19. PMID: 39560156. Note: sponsored by Medtronics®
5. Eckenhoff JE. Some anatomic considerations of the infant larynx influencing endotracheal anesthesia. Anesthesiology 1951;12(4):401-410. doi: 10.1097/00000542-195107000-00001, PMID: 14847223.
6. de Wit M, Peelen LM, van Wolfswinkel L, de Graaff JC. The incidence of postoperative respiratory complications : a retrospective analysis of cuffed vs uncuffed tracheal tubes in children 0-7 years of age. Paediatr Anaesth 2018 ; 28 (1): 210-217. doi : 10.1111/pan.13340, PMID: 29436138.
7. Greaney D, Russell J, Dawkins I, Healy M. A retrospective observational study of acquired subglottic stenosis using low-pressure, high-volume cuffed endotracheal tubes. Paediatr Anaesth 2018;28(12):1136-1141. doi : 10.1111/pan.13519, PMID: 30375105.
8. Kayashima K, Mizuyama H, Takesue M, Doi T, Imai K, Murashima K. Adjusting pediatric endotracheal tube depths relative to the cricoid by using longitudinal ultrasound images of the saline-inflated cuff in the trachea : two case reports. A&A Case Reports 2018 ; 10(9):235-238. doi: 10.1213/XAA.0000000000000673, PMID: 29708918.
9. Weiss M, Dave M, Bailey M, Gysin C, Hoeve A, Hammer J, Nicolai T, Spielmann N, Gerber A. Endoscopic airway findings in children with or without prior endotracheal intubation. Paediatr Anaesth 2013 ; 23 (1) : 103-100. doi : 10.1111/pan.12102, PMID: 23289772.