Page 92 - JSOM Summer 2018

Are the King LTS Laryngeal Tube and the Ambu AuraOnce
Laryngeal Mask Useful Airway Adjuncts for Military Medics?

1
Danny Regnér, CRNA *; Peter Frykholm, MD 2

ABSTRACT
1–4
Background: Airway management is a critical skill that may prehospital trauma victims. Failure to supply adequate
be essential in the battlefield. The aim of this study was to oxygenation may result in a quick death of the trauma pa-
determine if combat life savers and medics with no or lim- tient; a protected, unobstructed airway and adequate venti-
ited clinical experience could provide airway control using lation are required to prevent the patient from experiencing
5,6
the disposable laryngeal suction tube (LTS-D) and the Ambu hypoxemia. Various solutions to secure the airway in a
®
™
AuraOnce disposable laryngeal mask (LMA). Methods: combat setting have been implemented depending on the best
Eight military medics with limited clinical experience and practice, training, legal issues, medical culture, and environ-
no airway management experience secured the airway on 19 ment. 1,5,7,8 The best practice for securing an airway may be to
intrahospital anesthetized patients using the LTS-D and the use highly educated and experienced professionals for airway
LMA. Each patient was treated with both airway adjuncts in management in the battlefield. 5,8,9 Such personnel could be an-
a randomized order. Each medic was studied on at least two esthesiologists, nurse anesthetists, or other personnel who are
and not more than three patients. Success of insertion, num- highly clinically skilled in airway management (professional
ber of attempts, and time to correct placement with verified airway providers).
ventilation were recorded. Results: When using the LTS-D, the
first-attempt success rate for the medics with the first patient In the first line of combat operations, there is a shortage of
was 50% (four of eight) and 75% (six of eight) on the sec- this type of personnel. They need not only adequate medical
ond attempt. With the second patient, the first-attempt success skills but must also be able to perform combat operations and
rate was 87.5% (seven of eight), and on the third patient, it cope with the physical effort and stress of the battlefield. 11,12
was 100% (three of three). For all patients, the accumulated The shortage of medical personnel with these abilities and the
first-attempt success rate was 73.7% (14 of 19) and 84.2% demand of having a high alert status for deployment compel
(16 or 19) for second attempts with the LTS-D. The success many armed forces to lean on the permanent medics for first-
rate on first attempt with the LMA was 100% (19 of 19) on line casualty care.
the first patient. On the second intervention with the LMA,
there was a significant decrease in mean time to verified venti- An integral component of casualty care is airway manage-
lation, from 56.4 seconds to 27.7 seconds (p = .043), and time ment. According to Mabry et al. and Champion et al.,
14
13
to verified ventilation with no leakage, from 61.3 seconds to airway injuries needing airway interventions account for 1%
32.3 seconds (p = .029). Insertion attempts for three LTS-Ds to 1.8% of the deaths in a combat environment. Due to the
and one LMA failed. Conclusion: This study suggests that for need for upholding military skills, as well as demand for de-
the safe use of the laryngeal tube suction by inexperienced ployment and other tasks, it may be difficult for the military
airway providers, a clinical training program is required. The medics to uphold clinical airway skills on a level with profes-
LMA proved superior to the LTS-D with a 100% success rate sional airway providers. The methods of airways management
at the first attempt, which suggests that minimal training is used by military medics range from manual maneuvers (e.g.,
needed before clinical use. We therefore recommend the LMA chin lift, jaw thrust) to rapid sequence induction and surgical
as the primary airway adjunct for military medics, despite a cricothyrotomy.
hypothetically inferior protection from aspiration.
Due to the significant risk of fatal complications that can result
Keywords: airway; airway management; combat; education; from intubation 3,8,14 and the difficulty of performing endotra-
laryngeal tube; laryngeal tube suction; laryngeal mask; mili- cheal intubation in an military environment, alternate strate-
tary medicine; supraglottic airway gies for obtaining a more secured airway using medics with
minimal training and clinical skills were studied. This was an
attempt to mirror a worst-case scenario with medics deploying
with no or little clinical experience of airway management.
Introduction
Reports from the conflicts in Iraq and Afghanistan have An alternative to placing a cuffed tube and securing the airway
shown frequencies as high as 10.5% (range, 4.1%–10.5%) is using one of several types of alternative airway devices. The
regarding the use of advanced airway management in military criteria for a useful alternative airway device are that it should
*Correspondence to danny.regner@mil.se
1 Mr Regnér is a senior chief petty officer and nurse anesthetist serving in the Swedish Armed Forces. Dr Frykholm is an anesthesiologist at the
2
Department of Surgical Sciences, Section of Anaesthesiology and Intensive Care Medicine, Uppsala University, Uppsala, Sweden.
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