A Case of Laryngeal Granulomas After Oral and Maxillofacial Surgery With Prolonged Intubation

Abstract

Laryngeal granuloma development can be a postoperative complication of laryngeal trauma or irritation resulting from general anesthesia and endotracheal intubation. These rare benign lesions are located primarily over the cartilaginous portions of the larynx, particularly the vocal processes of the arytenoids. Airway manipulation during the intubation process and prolonged intubation periods can be contributing factors to intubation-related laryngeal granulomas, which may manifest 1 to 4 months after intubation. The patient in this case was a female who returned with complaints of throat pain without hoarseness or sensations of a “lump in her throat” 3 months following surgery, during which she was intubated with a 7.0-mm nasotracheal tube for 30 hours, likely contributing to her bilateral laryngeal granulomas. The patient underwent successful conservative medical management consisting of a proton pump inhibitor and an inhaled corticosteroid.

Laryngeal granulomas can arise postoperatively, often as complications following injury to or irritation of the mucosa overlying the arytenoid cartilage.^1–3 Laryngeal granulomas are rare, spherical, benign lesions located primarily in the posterior glottis, over the cartilaginous aspects of the arytenoids or vocal cords, and can occur either unilaterally or bilaterally.^1,3–5 Although laryngeal granulomas have several etiologies, the first report of a postintubation laryngeal granuloma was published by Clausen in 1932.^2,3,6 Many terms have been used to refer to a laryngeal granuloma, including arytenoid granuloma, vocal process granuloma, or vocal fold granuloma.^2,7,8 Clinical signs and symptoms of laryngeal granulomas can include dysphonia, hoarseness, sore throat, and dyspnea, which may not manifest until 1–4 months after extubation.^2,7–9

Common causes include mechanical trauma or irritation from an endotracheal tube (ETT; 23%), excessive vocal straining or overuse (33%), and gastroesophageal reflux disease (30%).³ Manipulation of the airway during intubation and prolonged periods of intubation are contributing anesthetic factors related to the development of laryngeal granulomas.^7,9–12 Laryngeal granulomas have reportedly been associated with intubations lasting 3.5 hours to more than 4 days.^1–3,10 Female patients are more likely to sustain intubation-related laryngeal granulomas because of a more narrow larynx and thinner arytenoid mucosa, which can contribute to an increased risk of laryngeal and tracheal injury.^1,2 Conservative medical management consists of prolonged treatment with proton pump inhibitors (PPIs) and corticosteroids,^6,13 and resolution may take 1 to 8 months.^3–5

We describe a case of intubation-related laryngeal granulomas following Le Fort 1 and sagittal split ramus osteotomies in a young female patient.

CASE REPORT

The patient was a 26-year-old woman (height = 160 cm; weight = 50 kg; body mass index = 19.5 kg/m²) previously diagnosed with skeletal class III jaw deformity and facial asymmetry. She was scheduled for bimaxillary surgery involving a bilateral mandibular set back and maxillary advancement under general anesthesia. The patient was generally healthy with no reported significant medical history, surgical history, medications, allergies, or other social issues. She denied any history of alcohol abuse, smoking, or any dyspnea or laryngeal discomfort, and the preoperative physical examination, airway assessment, laboratory testing, and chest and heart auscultation were all within normal limits.

On the day of surgery, the patient presented to the hospital and reported being appropriately nil per os for at least 8 hours prior to arrival. She was transferred to the operating room without any premedication, and standard anesthetic monitors were applied. General anesthesia was induced with intravenous boluses of midazolam (6 mg), atropine (0.25 mg), fentanyl (200 μg), and rocuronium (40 mg) with oxygen (6 L/min) via facemask after obtaining intravenous access. Following loss of consciousness, the patient was prepped with bilateral nasal cotton swabs soaked with a 2% lidocaine and 1:200,000 epinephrine solution prior to intubation. A preformed 7.0-mm nasotracheal tube (Portex Ltd, Hyth, Kent, UK) was successfully inserted under direct laryngoscopy on the first attempt without the use of Magill forceps. A Cormack-Lehane grade II view was obtained, and the ETT cuff was visualized passing beyond the vocal cords and therefore not suspected of impinging on the cords upon inflation (cuff pressure: 20–25 cm H₂O). Anesthesia was maintained with sevoflurane (1.4–1.7%) in air (1.7 L/min) and oxygen (1.3 L/min). In addition, supplemental fentanyl boluses (for a total of 1000 μg) and a continuous infusion of remifentanil (0.1–0.5 μg/kg/min) were administered for analgesia throughout the case. The patient was placed on controlled ventilation for the duration of the case. Blood pressure, heart rate, and end-tidal CO₂ were maintained at 78–121/40–58 mm Hg, 57–90 bpm, and 35–40 mm Hg, respectively. Bispectral index was maintained between 38 and 58 with a spectral edge frequency of 10–14 Hz and signal quality index of 90–95%. Following the procedure (424 minutes), the patient remained nasally intubated and was transferred to the intensive care unit for overnight monitoring. She remained sedated with continuous infusions of dexmedetomidine (0.2–0.5 μg/kg/h) and propofol (2–4 mg/kg/h) and mechanically ventilated using synchronized intermittent mandatory ventilation with no active coughing or “bucking” noted. She was successfully extubated without difficulty at 11 am the next day after confirming satisfactory spontaneous respirations. The patient was intubated for a total duration of approximately 30 hours. She was placed in intermaxillary fixation the day after surgery and was released 6 days later, at which point she was able to speak without any difficulty and reported no episodes of hoarseness, stridor, dyspnea, or sore throat. However, 3 months after the surgery and extubation, she presented with complaints of a sore throat, although she denied any dyspnea. Subsequent assessment by an otolaryngologist using a flexible fiber-optic scope revealed bilateral nodules consistent with laryngeal granulomas on her arytenoids (Figure 1). She was medically managed over the course of 3 months using the PPI vonoprazan (20 mg, once a day) and a budesonide inhaler (200 μg, twice a day). Two days after starting her medical management, she was reevaluated, and the laryngeal granuloma on the right side was noted to have decreased in size. Three months later, she again presented for reevaluation, and the laryngeal granulomas and complaints of a sore throat had completely resolved (Figure 2).

Figure 1.

Bilateral laryngeal granulomas (arrows) observed on the arytenoid cartilages 3 months after general anesthesia.

Figure 2.

Complete resolution of the bilateral laryngeal granulomas (arrow) 3 months after starting medical management.

DISCUSSION

Various etiologic or predisposing anesthetic factors related to the development of laryngeal granulomas have been suggested, including traumatic intubation or extubation, the use of an inappropriately large ETT, incorrect positioning or overpressurization of the ETT tube cuff, abnormal positioning of a patient's head, degree of flexibility and positioning of the ETT, and prolonged duration of intubation.^1,8,10–12 Other predisposing factors for the development of laryngeal granulomas include female gender, obesity, a short neck, and hereditary airway anomalies.^1,4,5 The prevalence of granulomas can be as high as 76% in patients who remain intubated for longer than 3 days.^2,3 Up to 60–90% of all intubation-related laryngeal granulomas are reported to have occurred in females.^1,2,4,12 A previous publication reported 16 patients who were treated for laryngeal granulomas, of which 9 were thought to be the result of tracheal intubation (4 were presumed to be caused by acid reflux and 3 were idiopathic).¹² All of these 9 intubated patients were treated initially with medical management, but only 2 responded to this conservative approach, necessitating surgical intervention for the remaining 7 patients.

The patient in this case was a female who remained intubated with a 7.0-mm ETT for 30 hours, which may have contributed to her developing laryngeal granulomas. Potential methods for decreasing the risk of laryngeal granuloma formation include avoiding prolonged intubation times, using smaller-sized ETTs, ensuring adequate ETT cuff pressures (between 20 and 30 mm Hg) and avoiding pressure extremes (>30 mm Hg), avoiding extreme extension or flexion of the patient's neck, and providing adequate muscle relaxation and depth of anesthesia.^1,13

Laryngeal granulomas often occur at the medial surface and vocal process of arytenoid cartilages with hyperplastic fibrous tissue because these cartilaginous structures are poorly vascularized and covered only by a thin mucosa.^2,6,14 The lack of soft-tissue protection might lead to ulceration of these areas, even with minimal trauma or irritation. Ulceration is considered an early stage of perichondritis, and a superimposed secondary infection can promote contact ulcers.³ The contact ulcer then becomes a sessile granuloma as the denuded area is recovered with granulation tissue. This is followed by the formation of an inflammatory polyp caused by proliferation of the centralized tissue beds and epithelization of the peripheral tissues.^2,7,10 These changes result in conversion of the sessile mass into a pedunculated pyogenic granuloma in the later stages of laryngeal granuloma development.

Laryngeal granulomas can be treated with conservative medical management or surgery.^2,4,5,8,15 Conservative treatment is the main initial strategy and focuses on the use of corticosteroids and PPIs, with inhaled corticosteroids often producing particularly good responses.¹ PPIs are useful to prevent further injury from gastroesophageal reflux disease.^3,4 The presence of acid regurgitation occurring in the immediate postoperative period following intubation and further irritating the laryngeal mucosa could predispose a patient to developing laryngeal granulomas. Therefore, patients with acid reflux should ideally continue GERD medications, such as PPIs, throughout the perioperative period, as acid reflux can prevent the epithelialization of damaged laryngeal tissues. Treatment using corticosteroids and inhaled budesonide alone can prolong the time until resolution of laryngeal granulomas.³ The use of combined therapy (ie, corticosteroids and PPIs) may accelerate laryngeal granuloma resolution. Patients should be advised to avoid large and/or late-night meals due to the potential for promoting gastric acid secretion.⁸ Surgical treatment of laryngeal granulomas should be reserved for therapeutic medical management failures^2,3; however, a high recurrence rate has been noted.^6,7,15 In this case, although the lesions were noticeably smaller 2 days after starting medical management and resolved completely within 3 months, attention was paid to the patient's progress, as laryngeal granulomas could lead to airway compromise and be life threatening.¹¹ It is advisable to recommend further consultation (ie, otolaryngology referral), possibly including assessment with a flexible fiber-optic scope, for patients with complaints of a persistent sore throat after surgery, including those involving shorter periods of intubation than present in this case.

CONCLUSION

Contributing factors to the development of laryngeal granulomas include female gender and prolonged intubation following oral and maxillofacial surgery, as noted in this case. It is important for anesthesiologists to consider ways of minimizing trauma or irritation to the laryngeal mucosa by using appropriately sized ETTs, monitoring cuff pressures, and providing adequate muscle relaxation and depth of anesthesia to reduce the risk of laryngeal granulomas developing after general anesthesia. In addition, further evaluation is likely indicated, should patients develop signs and symptoms consistent with laryngeal granulomas postoperatively, such as a persistent sore throat, dyspnea, or dysphonia.