Larry Mellick, MD, MS, FAAP, FACEP
Professor of Emergency Medicine and Pediatrics
Medical College of Georgia
Pearl: Even though the American Heart Association and the Pediatric Advanced Life Support (PALS) course have endorsed the use of cuffed endotracheal tubes,1 significant controversy remains, and for good reasons.
Discussion: The swing back to allowing cuffed endotracheal tubes in children younger than age 8 years has occurred. (See Figure 1.) The concern with cuffed tubes of the past has been impaired tracheal mucosal blood flow and an associated higher incidence of post-extubation laryngeal edema and tracheal stenosis. However, it is not well known that significant controversy remains regarding the use of cuffed endotracheal tubes in children.
In fact, there is some international evidence that cuffed endotracheal tubes are still not being used routinely by pediatric intensivists and anesthesiologists. In a small survey of United Kingdom pediatric critical care and anesthesia specialists, only 5% of PICU and 7% of anesthetic responders used cuffed tubes routinely. The most common reason cited in both groups for not using the cuffed tubes was that there was minimal perceived benefit to be gained over using an uncuffed tracheal tube.2 In a survey of 200 French pediatric anesthesiologists (130 responses), the cuffed endotracheal tube was used routinely by 25% of respondents for more than 80% of their patients, while more than 37% of respondents used them in fewer than 20% of the cases.3
The actual evidence as presented in a BestBETs October 2005 topic (built on a total of three relevant studies) titled, “Do cuffed endotracheal tubes increase the risk of airway mucosal injury and post-extubation stridor in children?” suggests as its clinical bottom line that:
“The use of low-pressure, high-volume cuffed endotracheal tubes is not associated with increased incidence of post-extubation stridor in children. (Grade C) There are no studies which adequately assessed potential long term consequences such as subglottic stenosis. (Grade D) In selected cases in whom high airway pressures are anticipated during their intensive care stay, cuffed endotracheal tubes can be used to avoid the need for re-intubation because of air leak around the ETT. (Grade C)”4
This favorable evidence is not all that impressive, and there are a number of other valid concerns regarding cuffed endotracheal tubes. First, the price of cuffed endotracheal tubes is problematic.
“…cuffed tubes remain many times more expensive than uncuffed tubes and are likely (to) remain so. On this basis alone it can be hard to justify the routine use of the cuffed tube provided equipoise between the two techniques remain.”5
Additionally, an editorial in a 2005 Canadian Journal of Anesthesia article outlined some of the practice concerns remaining with cuffed endotracheal tubes:6
“This may not be that important when an eight-year-old is being intubated, but for an infant or smaller child, the increase in airway resistance with a smaller tube may be clinically significant. For example, the trachea of a one-year-old may only be able to accept a 3.5 or even a 3.0 mm internal diameter (ID) tube when a cuff is present. For a one-year-old to breathe through a 3.0 tube as opposed to a 4.0 tube represents something in the order of a threefold increase in airway resistance (Poisseuille’s law). This increase in airway resistance translates to an increased work of breathing.
“In a comprehensive in vitro investigation of various cuffed endotracheal tubes, Weiss et al. concluded that ‘most cuffed pediatric tubes are poorly designed, in particular the smaller sizes.’ They observed that with the tube tip in mid-trachea, many cuffs were positioned within the larynx and, if the cuff was inserted 1 cm below the cords, many of the tube tips were ‘dangerously deep within the trachea.’”
Furthermore, in another 2009 Pediatric Anesthesia article, the authors provide a reminder that uncuffed endotracheal tubes also can cause mucosal damage of the pediatric airway.
“Although there are clinical situations where cuffed tubes may have an advantage over uncuffed tubes, both tube types may cause tracheal damage and this can have devastating consequences for the patient. We do not know the extent of potential side effects of cuffed tubes. Howeve,r with their increased use, more data will be available and we await further research into this topic. Ultimately, careful selection and placement of TTs, whether cuffed or uncuffed, is of utmost importance and relies on the clinician’s judgment and skill as well as patient criteria.”7
The bottom line is that the issue of cuffed vs. uncuffed ET tubes in children is not a cut and dried issue. We, as emergency physicians, need to be aware of the ongoing discussion and should be aware that many PICU and pediatric anesthesiologists still do not unanimously accept the cuffed ET tube as the preferred airway option for children.