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Three Part Question

In [paediatric patients requiring ventilation] is [the use of a laryngeal mask inferior to endotracheal intubation or bag-mask ventilation] in terms of [outcome]?

Clinical Scenario

A five year old child is rushed into the Emergency Department in cardiac arrest in the early hours of the morning. The circumstances leading to this are not clear. The paramedics have tried and failed to intubate the child. Two further unsuccessful attempts at intubation are made in the department. The paediatric anaesthetist has been called and is on her way but will not be there for some time. Reasonable chest expansion is possible using bag and mask ventilation although there appear to be a lot of secretions in the upper airway. You wonder if it is better to persist with bag and mask ventilation or if placement of a laryngeal mask would allow superior ventilation.

Search Strategy

Ovid MEDLINE and EMBASE November 2008.
[laryngeal mask.mp OR lma.mp] AND [pediatric.mp OR paediatric.mp OR child$.mp OR neonat$.mp OR infant.mp] AND [resuscitat$.mp OR emergenc$.mp OR ALS.mp OR PALS.mp OR APLS.mp OR life support.mp] LIMIT to humans and English language.

Search Outcome

278 papers were found. 1 Cochrane review was felt to be relevant to the clinical question.

Relevant Paper(s)

Author, date and country	Patient group	Study type (level of evidence)	Outcomes	Key results	Study Weaknesses
Grein AJ, Weiner GMG 2005 USA	Systematic review seeking trials including patients undergoing resuscitation as a neonate comparing ventilation via a laryngeal mask versus ventilation via either bag and mask or endotracheal intubation.	Only one relevant study found comparing LMA to ETT after an unsuccessful attempt at bag mask ventilation in neonatal resuscitation.	Successful first time placement	LMA 17/20, ETT 18/20.	Small study. Limited information about recruitment and allocation provided.
			Time to insert device (mean (SD))	LMA 10 (2.5) sec, ETT 7.5 (1.3)

Comment(s)

In paediatric patients who require ventilation during resuscitation due to cardiac or respiratory arrest endotracheal inubation is the ultimate method to allow adequate ventilation and protect the airway from aspiration of secretions or gastric contents. In circumstances where this is not possible due to technical difficulties or lack of trained personnel there may be a role for the laryngeal mask. While this does not protect the airway it may allow for superior ventilation with less risk of gastric distension compared with bag and mask ventilation. It may also be possible to ventilate the patient using a LMA in circumstances where neither intubation or ventilation have been possible. Unfortunately there is very little evidence to support an opinion which is understandable given the difficulties of conducting research in this area. The current APLS guidelines mention the LMA as an option to be considered in the terrifying "can't intubate, can't ventilate" scenario. [6] Various caveats are mentioned including the lack of protection against regurgitation and aspiration and the fact that the LMA, while easy to place, may be easy to dislodge. The American Heart Association guidelines suggest that LMAs are 'acceptable' when used by experienced providers. [2] The International Liaison Committee on Resuscitation Pediatric Working Group agreed that there was insufficient data to change current guidelines with regard to LMA versus ETT. [3] There are numerous case reports documenting successful use of LMAs in situations of failed intubations and some evidence from simulated cardiac arrests that LMAs may be easier to place than ETTs. [1] There is also one retrospective paper which suggests that the incidence of regurgitation may be lower in patients (non-paediatric) who are resuscitated using LMAs rather than bag and mask ventilation prior to ETT insertion.[4] The one paper that formed the basis of the Cochrane review did not show any benefit of the LMA over the ETT in terms of success rates or time for device insertion, in experienced hands, in neonatal resuscitation.[5]

Clinical Bottom Line

Given the lack of evidence the use of local guidelines are recommended. There may be a role for considering LMA in the "can't intubate, can't ventilate" situation while a surgical airway is being prepared.

Level of Evidence

Level 3 - Small numbers of small studies or great heterogeneity or very different population.

References

1. Chen L, Hsiao, A Randomized trial of endotracheal tube versus laryngeal mask airway in simulated prehospital pediatric arrest. Pediatrics 2008; 122(2) 294-7
2. American Heart Association 2005 American Heart Association (AHA) guidelines for cardiopulmonary resuscitation and emergency cardiovascular care of pediatric and neonatal patients:pediatric basic life support Circulation 2005; 112 IV1-203
3. Kattwinkel J, Niermeyer S, Nadkarni V, Tibballs J, Phillips B, Zideman D, Van Reempts P, Osmond M An advisory statement from the Pediatric Working Group of the International Liaison Committee on Resuscitation Middle East Journal of Anaesthesiology 2001; 16(3) 315-51
4. Stone BJ, Chantler PJ, Baskett PJ The incidence of regurgitation during cardiopulmonary resuscitation: a comparison between the bag valve mask and laryngeal mask airway. Resuscitation 1998; 38(1):3-6
5. Grein AJ, Weiner GMG Laryngeal mask airway versus bag-mask ventilation or entrotracheal intubation for neonatal resuscitation Cochrane Database of Systematic Reviews 2005; Issue 2
6. Advanced Life Support Group Advanced Paediatric Life Support (4th Edition) BMJ Books 2005