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A Novel Way to Secure the Laryngeal Mask Airway During Oral Surgery Procedures

Mireles, Ramiro MD*; Devgun, Ravinder DO*; Tucker, Blake DDS; Votta, Timothy MD; Chahal, Prabhdeep DMD; Ramsdell, Robert MD, MBA*; Heard, Christopher MBChB, FRCA*

doi: 10.1213/ANE.0000000000001540
Patient Safety
Free

The laryngeal mask airway (LMA) has been used successfully for an ever-increasing number of applications. Utilization in oral maxillofacial surgery has been hampered by surgical difficulties working around the device. In this case series, a novel device, the LMA-PROP, was used to determine whether it was possible to alleviate device-positioning concerns with third molar extraction cases. LMA-PROP was used with both anesthesia and surgical satisfaction in this small pilot study. LMA-PROP appears to be a helpful new tool allowing the surgeon to maintain current surgical techniques for third molar extraction while securing LMA adequately for anesthesia maintenance.

Published ahead of print August 29, 2016.

*Department of Anesthesia, Women and Children’s Hospital of Buffalo, Buffalo, New York; and School Dental Medicine, SUNY, University Pediatric Dentistry, Buffalo, New York.

Published ahead of print August 29, 2016.

Accepted for publication July 6, 2016.

Funding: University Pediatric Dentistry.

The authors declare no conflicts of interest.

This report was previously presented, in part, at the 2014 American Society of Anesthesiologists Meeting, October 2014, New Orleans, LA.

Reprints will not be available from the authors.

Address correspondence to Christopher Heard, MBChB, FRCA, Department of Anesthesia, Woman and Children’s Hospital of Buffalo, 219 Bryant St, Buffalo, NY 14222. Address e-mail to cheard@greatlakesanes.com.

Procedures performed by an oral surgeon in the hospital are usually performed under general anesthesia, securing the airway with a nasal tracheal tube that may put the patient at risk from complications of a nasal intubation.1–3 Thus, the laryngeal mask airway (LMA) is an attractive alternative for oral surgical procedures such as tonsillectomy and adenoidectomy4 and may be associated with fewer postoperative airway complications.5 In these cases, a mouth gag placed by the surgeon secures the LMA in place so that it cannot move while the large cuff on the LMA acts as a trap for blood or secretions, which can then be suctioned clean before removal of the LMA. This procedure is most often performed using a flexible LMA6 because of its reinforced structure and smaller diameter compared with the standard disposable LMA.

Figure 1.

Figure 1.

To facilitate the use of an LMA anesthetic for removal of the third molars in the hospital setting, we have designed a device (LMA-PROP) that is very similar to the mouth prop currently used routinely in all third molar extractions (Figure 1A and B). A mouth prop routinely used after sedation has been given to the patient, allowing for better surgical exposure. The mouth prop is removed and replaced during the procedure as the surgeon moves from 1 side of the mouth to the other. Our LMA-PROP has been modified to allow a flexible LMA (size 3 or 4) to be snapped in and secured for the procedure and allows the oral surgeon to easily manipulate the LMA during the surgery.

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METHODS

This pilot prospective case series evaluated the LMA-PROP in a convenience sample of healthy teenagers (American Society of Anesthesiologists physical status II) and young adults (aged 14 years and older) undergoing elective third molar extractions under general anesthesia in a hospital operating room setting. Subjects had to be suitable for a size 3 or 4 LMA with no abnormal airway anatomy.

LMA-PROP was custom-manufactured by a local company (Great Lakes Orthodontics, Tonawanda, NY) and is made of silicone elastomer, a material commonly used for oral devices such as sleep appliances and orthodontic appliances. LMA-PROP was made using a liquid injection molding process out of a liquid silicone rubber. These rubbers are intended for high-strength molded devices that may be used for up to 28 days as medical applications. The LMA-PROP can be custom-designed to fit any size LMA. In our study, 1 set of 2 LMA-PROPs fit a size 3 LMA and another set fit the size 4 LMA. The LMA-PROP was placed between the upper and lower molars to provide surgical exposure and an armored LMA snapped into a groove molded on the lingual side of the LMA-PROP. The device could be used as long as the surgery does not require total occlusion of the upper and lower teeth and as long as adequate surgical exposure can be obtained. After use, the LMA-PROP is sterilized in a dental autoclave as per dental surgery protocol for all oral devices and mouth props.

Institutional review board approval and informed consent were obtained from each subject. After placement of standard American Society of Anesthesiologists monitors (pulse oximeter, noninvasive blood pressure manometer, and EKG), anesthesia was induced using inhalation of sevoflurane, nitrous oxide, and oxygen. An intravenous cannula was then placed. A size 3 or 4 flexible disposable LMA (LMA Disposible; LMA North America) was placed to secure the airway, and correct placement was confirmed by the presence of ETcO2 on capnography, auscultation of bilaterally equal breath sounds, ease of assisted ventilation, and a standard carbon dioxide waveform during spontaneous ventilation. Anesthesia was maintained with 3% sevoflurane and nitrous oxide and oxygen in a mixture from 50% to 67%. In addition, ondansetron (0.1 mg/kg, maximum 4 mg), ketorolac (0.5 mg/kg, maximum 30 mg), and dexamethasone (10 mg) were administered to all subjects.

Oral surgeons used the new LMA-PROP to secure the LMA (Figure 2) and commence with injection of local anesthesia and surgical removal of the third molars. On completion of extractions on 1 side, another LMA-PROP was inserted on the opposite side of the mouth to provide surgical access, and the LMA was repositioned into the new LMA-PROP. If the use of the LMA or the LMA-PROP was unsatisfactory, defined by inadequate or partially obstructed respiration through the LMA, dislodgement of the LMA, inability to place LMA appropriately, inability to provide positive pressure ventilation through the LMA, or laryngospasm, the patient was given a neuromuscular blocking drug and intubated through a nasal endotracheal tube.

Figure 2.

Figure 2.

At the end of each procedure, anesthetic gases were discontinued, and the LMA was removed. A follow-up phone call was made within 48 hours to access for any surgical or airway complications.

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RESULTS

Table.

Table.

Figure 3.

Figure 3.

Figure 4.

Figure 4.

Twelve patients were recruited, and of those, 2 patients did not participate in the LMA-PROP evaluation (correct size LMA-PROP not available). Patient ages ranged from 16 to 34 years with an average weight of 87 ± 15 kg. Subjects underwent anesthesia for third molar extractions, and all surgical procedures were completed satisfactorily. Average procedure time was 24 minutes, and the majority of patients received an average of 100 μg fentanyl during the procedure. Several changes to the LMA-PROP were made during this initial evaluation because of difficulties inserting the LMA into the LMA-PROP. Thus, we modified the lip that the LMA inserts into for all subsequent devices (Figure 3). “Slippage” of the LMA-PROP on the teeth while it was positioned in the mouth resulted in the addition of ridges to the biting surface after the fifth patient (Figure 4). LMA-PROP was successful for all but 1 patient in whom an nasal endotracheal tube was utilized because of suboptimal surgical exposure secondary to an abnormally small oral cavity. One incident of lip abrasion occurred secondary to surgical retractors, but there were no serious airway complications and no complaints recorded during patient follow-up. The surgeon’s assessment of LMA-PROP is shown in the Table. Overall, all parameters assessed were satisfactory, including the anesthesiologist’s assessment (Table), and no significant changes occurred regarding cardiorespiratory parameters throughout the anesthetic.

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DISCUSSION

LMA continues to be a popular option for several otolaryngology procedures.8 Our case series evaluated a novel and successful device to secure a LMA during oral surgery procedures. The new LMA-PROP allowed for surgical access while providing a secure and patent airway that allows for positive pressure ventilation if necessary. This provides considerable benefit over deep sedation techniques during which airway issues such as obstruction or apnea may be more difficult to manage.

During evaluation, several changes were made to the LMA-PROP to enhance performance such as the addition of ridges and modification of the lip into which the LMA is inserted (Figures 3 and 4). We engineered theses minor modifications to strike a balance between security of the airway and ease of attachment. Even so, we recognize that this technique and device may not be suitable for use in all8 such patients as those with a worrisome Mallampati score or short thyromental distance. This may reflect a reduced oral–pharyngeal volume and could be predictive of inadequate surgical exposure.

The soft silicone material used to create the LMA-PROP decreases the possibility of intraoral trauma, and it can be disinfected and sanitized daily (reused with sterilization up to 30 times without deterioration). However, slight color change was noted after several cleanings (Figure 3).

The LMA-PROP was custom-fabricated at a cost of approximately $170.00 (US dollars) each. However, with multiple uses, the patient cost is reasonable, and we speculate that other uses are also possible for this device, eg, an intensive care unit patient who grinds or bites their teeth on an oral endotracheal tube potentially interfering with respiration.

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DISCLOSURES

Name: Ramiro Mireles, MD.

Contribution: This author helped with the study concept, patient recruitment and research protocol, and helped write the manuscript.

Name: Ravinder Devgun, DO.

Contribution: This author helped design study and IRB process, helped with patient recruitment and research protocol, and helped write the manuscript.

Name: Blake Tucker, DDS.

Contribution: This author helped design the study and IRB process, helped with patient recruitment and research protocol, and helped edit the manuscript.

Name: Timothy Votta, MD.

Contribution: This author helped with patient recruitment and research protocol, helped analyze and interpret the data, and helped edit the manuscript.

Name: Prabhdeep Chahal, DMD.

Contribution: This author helped with patient recruitment and research protocol, and helped edit the manuscript.

Name: Robert Ramsdell, MD, MBA.

Contribution: This author helped with patient recruitment and research protocol, helped analyze and interpret the data, and helped edit the manuscript.

Name: Christopher Heard, MBChB, FRCA.

Contribution: This author helped create the study concept, helped design the study and IRB process, helped analyze and interpret the data, and helped write and edit the manuscript.

This manuscript was handled by: Richard C. Prielipp, MD, MBA, FCCM.

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REFERENCES

1. Watt S, Pickhardt D, Lerman J, Armstrong J, Creighton PR, Feldman L. Telescoping tracheal tubes into catheters minimizes epistaxis during nasotracheal intubation in children. Anesthesiology. 2007;106:238–242.
2. Tintinalli JE, Claffey J. Complications of nasotracheal intubation. Ann Emerg Med. 1981;10:142–144.
3. Harvey DC, Amorosa P. Traumatic nasotracheal intubation. Anaesthesia. 1986;41:442.
4. Doksrød S, Løfgren B, Nordhammer A, Svendsen MV, Gisselsson L, Raeder J. Reinforced laryngeal mask airway compared with endotracheal tube for adenotonsillectomies. Eur J Anaesthesiol. 2010;27:941–946.
5. Sierpina DI, Chaudhary H, Walner DL, et al. Laryngeal mask airway versus endotracheal tube in pediatric adenotonsillectomy. Laryngoscope. 2012;122:429–435.
6. Flynn P, Ahmed FB, Mitchell V, Patel A, Clarke S. A randomised comparison of the single use LMA flexible with the reusable LMA flexible in paediatric dental day-case patients. Anaesthesia. 2007;62:1281–1284.
7. Mandel JE. Laryngeal mask airways in ear, nose, and throat procedures. Anesthesiol Clin. 2010;28:469–483.
8. Lalwani K, Richins S, Aliason I, Milczuk H, Fu R. The laryngeal mask airway for pediatric adenotonsillectomy: predictors of failure and complications. Int J Pediatr Otorhinolaryngol. 2013;77:25–28.
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