Q&A: FAQs about pediatric laryngeal tubes for prehospital airway management
Infants and neonates need unique laryngeal tubes for pediatric airway management. Learn how best to deploy them from a field expert.
Sponsored by Ambu
By Jonathan Lee for EMS1 BrandFocus
Using pediatric laryngeal tubes requires a gentle touch and knowledge on how best to deploy.
To get key questions answered about pediatric laryngeal tubes for prehospital airway management, I spoke with Tom McGrail, a biomedical engineer and the director of clinical services with Ambu.
Ambu developed the King LTS-D disposable laryngeal tube for adult prehospital airway management and recently introduced the King LTS-D in size 0 and 1 for infants and neonates. McGrail addressed some common questions about using the King LTS-D in pediatric sizes.
What are the anatomical differences between adult and pediatric laryngeal tube insertion?
In addition to the smaller size airway, the larynx is higher in the neck, and the epiglottis is proportionately larger in infants. This can sometimes make it difficult to insert the tube around the corner in the oropharynx and seat the tip properly in the upper esophagus.
What are the traditional techniques for pediatric laryngeal tube insertion?
Sniffing position and towel rolls under the shoulders are two of the more traditional teachings around head position for pediatrics.
Are there alternative insertion techniques for a pediatric laryngeal tube?
There is a slightly different insertion technique, where a finger is placed on the back of the device during insertion to help guide it around the corner. Alternatively, a chin lift can make room for the device by displacing the tongue.
What is the first step to take if I am having trouble with inserting a pediatric laryngeal tube?
First, check the level of the insertion to ensure it’s getting around the corner. Chin lift and jaw thrust (if not contraindicated by C-spine injury) can be used to make space, while other options include displacing the tongue with a tongue depressor or even a laryngoscope.
Are there other troubleshooting steps for pediatric laryngeal tube insertion?
Make sure the device is seated properly, meaning its tip is in the upper esophagus and the ventilatory openings of the laryngeal tube are aligned with the tracheal opening to permit ventilation. To facilitate this alignment, it is suggested to err on the side of deep insertion, then inflate the cuffs and assess ventilation. If the air entry is poor, slowly withdraw the device while bagging until ventilation improves.
Although highly unlikely, it is conceivable that the device may be inserted into the trachea; if this happens, the device must be withdrawn and reinserted.
Should I worry about cuff pressure when inserting pediatric laryngeal tubes?
We have always suggested limiting cuff pressures. In adults, the cuff pressure should be limited to less than 60cmH20. In kids, the evidence is still being collected but should be less than40cmH20.
We recognize there is a tendency to overinflate the cuff when it is used emergently. It is suggested that once the airway is in and functioning, the cuff pressure becomes part of the reassessment. The air in the cuff can be adjusted; only use the minimum volume of air necessary to maintain a good ventilatory seal to reduce the risk of over-inflation.
Should I worry about airway anomalies with pediatric laryngeal tubes?
As with any supraglottic airway, anomalies that affect the upper airway or upper esophagus can affect device insertion and the ability to seat it properly. In certain cases, such as tonsillar hyperplasia, the tubular design of the King makes for easier insertion compared to other supraglottic devices.
Can I use a ventilator on King LTS-D pediatric laryngeal tubes?
Yes! The double cuff design of the King LTS-D provides an excellent seal to allow positive pressure ventilation. In adults, ventilatory pressures in excess of 30cm H2O can be employed; smaller pediatric patients typically require lesser pressures. The esophageal balloon seal minimizes gastric insufflation and the King LTS-D has a port for inserting a gastric tube that, even in the absence of a gastric tube, can provide a path for air and fluids to escape.