When the Supraglottic Airway Device is the Problem, not the Solution!

Introduction

Supraglottic airways are commonly used for airway management in both emergency and elective settings due to their high success rates and ease of use.¹ Advantages associated with these airways include decreased incidence of desaturation as compared to mask ventilation, decreased anesthetic dosing, and decreased incidence of dysphonia as compared to endotracheal intubation.² However, there have been cases reported of supraglottic airway malfunction or breakage.

One case reported a perforation of the laryngeal mask bulb after multiple attempts at jugular vein cannulation in a newborn patient.³ Yamaguchi et al. described an incident where an inadequate bite block, placed for electroconvulsive therapy resulted in the partial breaking of the LMA® and minor oral lacerations to the patient.⁴ Yadav et al. reports a case of an oblique fracture of the shaft of an LMA® that had been reused 54 times.⁵ We present a novel case of a disposable LMA® (Teleflex, Morrisville, NC) which fractured without any trauma, after insertion into the airway. To our knowledge, this is the only known case of a structural failure of the LMA® unrelated to user error.

Case Description

A 77-year-old female (150 cm., 38.5 kg, BMI 17.37kg/m²) presented for intramedullary rodding of the left tibia after a fall. The airway exam was unremarkable, with a thyromental distance greater than three finger breadths, full neck ROM and good oral opening with Mallampati grade III. For the management of the airway during the case, it was decided to place an LMA®. After induction with propofol the patient had an uneventful placement of a size 3 LMA®. The patient breathed spontaneously with no pressure support. Appropriate tidal volumes and respiratory rates were achieved. Twenty minutes into the case, the patient developed inadequate tidal volumes and desaturation. Manual ventilation was attempted with elevated peak pressures and again inadequate tidal volumes and significantly decreased levels of ETCO₂. Under the presumption that the LMA® had moved and was obstructing airflow, the airway was repositioned without any change in the low ETCO₂. During the reposition, the shaft of the LMA® came out of the patient’s mouth, leaving the mask portion in the airway. (Figure 1)

After manually removing the mask portion of the LMA®, the patient was successfully ventilated by mask. A muscle relaxant was given, and the patient was subsequently intubated with a size 7.0 ETT. The case proceeded without further incident, and the patient was uneventfully extubated at the end of the surgery.

Discussion

Structural failures of supraglottic devices are rare with very few cases reported in the literature as noted previously. We did report our experience to the manufacturer and received notice that the root cause was traced to a likely manufacturing defect which was being addressed.

Testing the integrity of the device prior to placement in the larynx can reassure the operator of the structural soundness of the device and removes the possibility of failure from that cause during the case. Furthermore, if a patient with a supraglottic airway in situ appears to have sudden difficulty in ventilation, supraglottic device failure should be on the differential diagnosis albeit low on the list of possible causes. We have now incorporated a simple test to evaluate whether the adhesive joint between the shaft and the mask is appropriately firm and feel confident that it will serve the purpose for which it is designed. We do this by preoperatively gently twisting the shaft of the mask by rotating clockwise and counterclockwise. Structurally appropriate devices should have zero give at the joint with this maneuver.

 

Ashish C. Sinha, MD, PhD, MBA, MSEd
Riverside University Health System, Moreno Valley CA, Loma Linda University, Loma Linda CA

Natalie Garcia Perez, BA
University of California Riverside, Riverside CA

Haad Arif, BS
University of California Riverside, Riverside CA

Viet Scott Nguyen, DO
Riverside University Health System, Moreno Valley CA

Jeffrey Thomas, DO
Riverside University Health System, Moreno Valley CA

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All authors have no conflict of interest related to this report.

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References

1. Benumof JL. Laryngeal mask airway. Indications and contraindications. Anesthesiology. 1992;77(5):843-846. doi:10.1097/00000542-199211000-00001
2. Jannu A, Shekar A, Balakrishna R, Sudarshan H, Veena GC, Bhuvaneshwari S. Advantages, Disadvantages, Indications, Contraindications and Surgical Technique of Laryngeal Airway Mask. Arch Craniofacial Surg. 2017;18(4):223-229. doi:10.7181/acfs.2017.18.4.223
3. Orfei P, Almenräder N, Patrizio A, Bigetti E, Pinto G. [Laryngeal mask perforation: complication of jugular vein cannulation in a newborn]. Anaesthesist. 2002;51(6):467-469. doi:10.1007/s00101-002-0327-4
4. Yamaguchi S, Mishio M, Okuda Y, Kitajima T. [Damage of a laryngeal mask airway during anesthesia]. Masui. 2000;49(7):762-764.
5. Yadav M, Sandeep G, Mahesh R, Gopinath R. Fractured laryngeal mask airway: Hazards of excessive reuse. Anesth Essays Res. 2015;9(3):453-454. doi:10.4103/0259-1162.161808

Sinha et al. report an unusual failure of a supraglottic airway that was fortunately identified and managed without any patient harm. In their report, they propose a pre-use test process to evaluate the supraglottic airway. There are no data to confirm the utility of this test for identifying faulty devices or preventing recurrence.