Difficult Airway Management in Oromaxillofacial Tumor Surgery: Two Case Reports and Review of the Literature

Abstract

Difficult airway management in oromaxillofacial tumor surgery poses significant challenges for anesthesiologists. We present two case reports of patients with mandibular malignant tumors and maxillary osteosarcoma who underwent surgery under general anesthesia. Preoperative assessment revealed a mass involving the right mandible, completely covering the inside of the mouth and invading the floor of the mouth in the first case, and a mass in the left maxilla extending to the zygomatic arch and orbital floor in the second case. Both patients had limited mouth opening, making direct laryngoscopy impossible. Awake fiberoptic intubation was planned to secure the airway while preserving spontaneous breathing. Sedation was achieved using dexmedetomidine, propofol, and ketamine. The fiberoptic bronchoscope was inserted through the nasal cavity, and the endotracheal tube was advanced once the vocal cords were visualized. Muscle relaxation was induced with rocuronium after confirmation of tracheal placement. Both patients underwent extensive surgical resection and reconstruction procedures. Postoperatively, they were managed in the intensive care unit and subsequently transferred to the ENT service after successful weaning from mechanical ventilation.These cases highlight the importance of thorough preoperative assessment, multidisciplinary planning, and the use of advanced airway management techniques such as awake fiberoptic intubation in patients with oromaxillofacial tumors presenting with anticipated difficult airways.

Introduction

Appropriate planning is crucial for preventing morbidity and mortality when airway management is difficult. Many guidelines developed by national societies have focused on the management of the difficulties encountered in unconscious patients; however, there are few guidelines in the literature on how best to approach a patient with a predicted difficult airway. Previously published prediction criteria for difficult direct laryngoscopy have been widely recognized [1]. Several studies have documented increased patient morbidity associated with multiple attempts at tracheal intubation. Therefore, when difficulty is anticipated, tracheal intubation after the induction of general anesthesia should only be considered when a maximum of three attempts with the selected device(s) can be predicted. Simultaneous predicted difficulty using oxygenation with a face mask or supraglottic device makes the awake approach advisable. Issues such as patient compliance, availability of skilled assistive personnel, and clinician experience should also be considered when deciding on an appropriate treatment strategy. With appropriate airway assessment and consideration of relevant contextual issues, a rational decision can be made as to whether an awake approach to tracheal intubation will maximize patient safety or whether airway management can safely continue after induction of general anesthesia. Given the anticipated difficulty, close attention should be paid to the details of the implementation of the chosen approach. This should include a plan for tracheal intubation or patient oxygenation fails [2]. Otolaryngology (ENT) surgery requires an anesthesiologist and surgeon to work together in a difficult and confined space. Preoperative multidisciplinary preparation should be performed for the administration of anesthesia in patients undergoing head and neck surgery [3]. These patients, who usually have airway obstruction due to tumors, are candidates for difficult intubation and difficult extubation [4]. Lack of mouth opening due to oromaxillofacial and mandibular tumors, airway stenosis, airway obstruction, malnutrition due to malignancy, cachexia, anemia, and dehydration should also be considered [5]. Awake intubation is indicated for difficult airways when attempting to secure the airway after induction of general anesthesia, which may cause harm due to potential difficulties or failures in these attempts. Traditional awake flexible bronchoscopic intubation is performed nasally or less commonly orally [6]. Awake video laryngoscopy is a new option in airway management that is gaining increasing interest as an alternative to awake endoscopy-guided intubation [7]. In direct comparisons with awake flexible endoscopic intubation, awake video laryngoscopy showed satisfactory intubation times and high acceptance by patients and anesthesiologists. However, certain cases, such as limited mouth opening or subglottic masses, require awake flexible endoscopic intubation [8]. However, awake video laryngoscopy cannot completely replace flexible endoscopic intubation. It is a convenient option, but it should be considered that this technique is not suitable for all types of airways, patients, or anesthesiologists. Specialization and sufficient practical experience are required for both the techniques. Careful planning, appropriate equipment, and experience with video laryngoscopy are crucial for a successful intubation [9]. Although the introduction of the video laryngoscope, introducer, and other assistive devices has partially changed its role in difficult airway management, the fiberoptic bronchoscope remains the first choice for most difficult airways [10]. We aimed to share the anticipated difficult airway management of two patients who underwent surgery under general anesthesia for mandibular malignant tumors and maxillary osteosarcoma in our ENT clinic. We decided to perform awake fiberoptic intubation because of the high risk of bleeding if the tumors covered the inside of the mouth and were traumatized.

Case Report 1

A 28 years old, 45 kg was admitted with a complaint of rapidly growing swelling on the face for 7 months. The patient was diagnosed with a malignant mandibular neoplasm, and surgery was planned by the ENT clinic. On preoperative anesthesia evaluation, the patient did not have any systemic disease. Examination revealed a mass involving the right mandible from the mentum to the condyle, completely covering the inside of the mouth and invading the floor of the mouth. The patient had a cachectic appearance due to prolonged malnutrition, and mallampathy evaluation could not be performed because the mass filled the entire oral cavity. Preoperative appearance of the patient in Figure-Case1a. Figure-Case1b before intubation.

The laboratory results were normal. Hb: 10.6 grdl⁻¹, it was thought that the patient might have had hemoconcentration due to dehydration. Blood pressure, 90/55 mmHg (hypotensive due to dehydration due to prolonged malnutrition); pulse, 120 min⁻¹ (tachycardic). Computed tomography (CT) showed a 10 cm mass in the right half of the face invading the mandible and maxilla at the widest point. The patient who was given ASA-2 risk had no mouth opening, and laryngoscopy could not be performed due to the tumor covering the jaw and oral cavity. Awake nasal intubation was planned under sedation with a flexible bronchoscope while preserving spontaneous breathing.

Dexmetedomidine 0.7 mcgkgh⁻¹ intravenous infusion (IV inf.), propofol 1 mgkg⁻¹ IV Ketamine 2 mgkg⁻¹ IV were administered ( Dexmetetomidine was infused to maintain respiration. Intermittent low doses of propofol were administered intravenously when inadequate. Sedation was supported with Ketamine due to hypotensive state. Total 40 mg Propofol and 40 mg Ketamine were administered. In this way, there was no drop in blood pressure values. Oxygen saturation did not decrease. Heart rate did not increase much. Hemodynamics did not change depending on the procedure. It was stable. A flexible bronchoscope was inserted through the nasal cavity and the tube was advanced when the vocal cords were visible. After visualization of the trachea and carina, 40 mg rocuronium IV was administered to induce muscle relaxation. 3000 ml IV fluid inf. A total of 6000 ml crystalloid, 500 ml colloid, 3 erythrocyte suspensions, and 2 Fresh Frozen Plasma IV were administered to the patient who subsequently started diuresis. Right hemimandibulectomy, partial maxillectomy, neck dissection, resection of the floor of the mouth, repair with a pectoral myocutaneous flap, and tracheostomy were performed. The patient was hospitalized in the postoperative intensive care unit with stable hemodynamics and was connected to a mechanical ventilator. Figure-Case1c shows the patient on the first postoperative day.

One day postoperatively, the patient was weaned off the ventilator and transferred to the ENT service as he was oriented and cooperative.

Case Report 2

41 years old, male, admitted to the ENT clinic with a complaint of a mass growing in the upper palate in the previous month. On examination, a mass originating from the maxillary region and invading the oral cavity was observed. CT tomography revealed a mass compressing the nasal cavity and nasopharynx. The tomography images of the patient in Figure-Case2a and Case2b.

The patient was scheduled to undergo surgery for a diagnosis of maxillary osteosarcoma with ASA-2 risk; however, laryngoscopy could not be performed because the tumor filled the oral cavity and had bleeding potential. As the nasal cavity was also closed with the mass, oral endotracheal intubation was planned to be performed with a flexible bronchoscope under sedation by preserving spontaneous respiration. Remifentanil IV inf. Propol 1 mgkg⁻¹ IV and Ketamine 2 mgkg⁻¹ were administered to the patient, and a flexible bronchoscope was carefully inserted through the oral cavity. After the trachea and carina were visualized, rocuronium 50 mg IV was administered, and the tube was placed in the trachea. Peroperative appearance of the mass in Figure-Case2c.

After excision of the mass, the patient was fully awake and extubated. The patient was oriented and cooperative during spontaneous breathing and was transferred to the ENT service. (Since there was no nasal cavity passage with flexible bronchoscopy, the tube was inserted softly into the trachea by crossing the vocal cords very carefully from the oral cavity without bleeding the tumor. After complete surgical removal of the tumor, the patient was carefully extubated. The patient, who had no hoarseness, speech difficulty and was oriented and cooperative, was sent to the ENT service fully awake and painlessly).

Discussion

ENT surgery ranges from simple procedures, such as tonsillectomy, to complex surgeries, such as major cancer operations and large free flap reconstruction. In ENT, the surgical site involves the upper respiratory tract. It also includes patients with airway obstruction and a severely deformed airway anatomy. The use of special surgical equipment, specialized surgical techniques, and procedures that require sharing the airway increases the importance of anesthesia and postoperative intensive care. It is important to examine the preoperative patient in detail and perform the necessary examinations, especially to determine the pathologies that cause obstruction in the upper airway and to determine the anesthesia strategy [3]. Clinical evaluation and physical examination alone may fail to predict airway obstruction accurately. Advanced imaging modalities can improve airway assessment, help formulate precise airway management strategies, and guide complex treatment decisions. Table 1 describes the imaging modalities used to predict difficult airways [11].

Table 1.

Diagnostic modalities in the prediction of difficult airway

Modality	Use
X-rays	Assess airway structures
USG (Ultrasonography)	Identify cricothyroid membrane, DA prediction
CT scan (Computed tomography scan)	Finer characterisation of pathology, image reconstruction
MRI (Magnetic resonance imaging)	Define soft tissue airway lesions
Nasal endoscopy	Bedside visualisation of glottis and subglottic areas
Virtual endoscopy	Internal virtual evaluation of airway
3D printing (Three-dimensional printing)	Simulated airway model enables planning, practice and education

We utilized CT imaging in our cases because the mass completely filled the oral cavity, and detailed physical examination was insufficient.

Difficult airways are common in ENT surgery. Contractures from previous treatments are common in patients with head and neck cancer. This can cause external deformities and restricted neck movement. Stiffness and disruption of pharyngeal tissues may impair mask ventilation and interfere with conventional laryngoscopy. A difficult airway is also a risky condition in terms of life-threatening complications after extubation and medicolegal issues [4, 12]. Since it is of great importance to ensure airway patency during preoperative anesthesia preparation, what and how should be determined in advance, and all precautions should be taken. From simple to severe cases, tools such as spark plugs in direct laryngoscopy, videolaryngoscopy, and flexible bronchoscopy are used, and in cases where these are insufficient, a tracheostomy set should also be available. Table 2 describes the devices used for airway management [11].

Table 2.

Developments in airway devices

Airway devices	Advantages
Direct Laryngoscopes	Light emitting diode/fibreoptic light, rechargeable batteries, MRI compatible, single use versions
Video laryngoscopes	Large screen, ability to record images and videos, specialised blades for difficult airways
Glidescope core	Enables dual bronchoscopy and video laryngoscopy
Fibreoptic bronchoscopes	Enables awake intubations, large screen, ability to record images and videos
Optical stylets	Small profile enables insertion into small mouth openings, allows for little cervical spine movement
Various versions of Supraglottic airways	Ease of insertion, rescue device for ventilation, conduit for intubation, provide for the administration of volatile anaesthetics

All the techniques are prone to failure. Therefore, it is necessary to know the maximum number of alternatives to successfully treat even the most challenging airways [13].

Head and neck surgery poses a threat to perioperative airway patency. Difficult airway management is associated with significant morbidity, and can potentially lead to hypoxic brain injury and even death. Airway management after maxillofacial microvascular reconstruction is an essential part of the perioperative management. In oral cavity microvascular reconstruction, the airway is potentially compromised by airway edema, flap edema or volume, hematoma formation, or upper airway sequelae of surgery. Classical teaching advocates elective tracheostomy in patients undergoing maxillofacial free-flap reconstruction, while others keep patients intubated overnight (delayed extubation). The optimal method of perioperative airway management remains debatable. However, a study by Madgar et al. showed that routine elective tracheostomy is unnecessary in maxillofacial microvascular free-flap reconstruction. Elective tracheostomies should be considered on a case-by-case basis [14]. Local institutional protocols should be developed for perioperative or postoperative care for elective tracheostomy. Patients without tracheostomy have been reported to have shorter hospital stays. All decisions regarding airway management in head and neck surgery should be agreed upon by the surgical, anesthesia, and intensive care teams [15].

Pediatric cases of successful intubation with a fiberoptic bronchoscope during oromaxillofacial tumor surgery have also been reported [5]. Studies have reported that successful nasotracheal intubation using videolaryngoscopy and Spark plugs in maxillary tumor surgery may be an alternative to fiberoptic bronchoscopy [16]. However, in our cases, we preferred fiberoptic intubation because mouth opening could not be achieved and the tumor completely covered the oral cavity. In a study conducted in patients who underwent elective surgery and who were thought to have a difficult airway in the preoperative evaluation, it was reported that the use of fiberoptics was the gold standard and should be included in anesthesia training [17]. In preoperative evaluation, there may be patients with a normal examination result who may have an unpredictable and unexpected difficult airway. Orotracheal intubation using a fiberoptic bronchoscope in patients with congenital or acquired undiagnosed tracheal stenosis has been reported [18]. In tracheal intubation performed with a fiberoptic bronchoscope in patients with difficult airways, intubation under sedation while preserving spontaneous breathing is important for airway safety. There are also studies comparing anesthetic agents that emphasize the importance of sedation [19]. Figure 1 shows the difficult airway algorithm published by (American Society of Anesthesiologists) in 2022.

Fig. 1.

Difficult airway algorithm published by ASA (American Society of Anesthesiologists)

Patients with difficult airways who undergo head and neck surgery are as difficult to extubate as they are to intubate. Emergency intervention and planned extubation are associated with a higher rate of complications during and immediately after intubation, including.

• Laringospasm

• Postextubation airway edema

• Postoperative airway obstruction

• Re-intubation is needed

Extubation was an elective procedure. It is therefore important to plan and execute this well. The aim was to ensure uninterrupted oxygen delivery to the patient's lungs, avoid airway stimulation, and have a backup plan to allow ventilation and reintubation with minimal difficulty and delay if extubation fails. The extubation guidelines of the Difficult Airway Association have recognized the concept of a stepwise approach. This approach has been used to aid decision-making and safe management of extubation [20]. The guidelines describe the following four steps:

• Step 1 Plan extubation

• Step 2 Prepare for extubation

• Step 3 Perform extubation

• Step 4 Post-extubation care: recovery and follow-up

They published three guidelines: basic, low risk, and risky. We wanted to share the DAS extubation guideline in Fig. 2: the ‘risky’ algorithm, as it is relevant to our cases.

Fig. 2.

DAS extubation guideline: ‘at risk’ algorithm

Our first patient who underwent surgery for a mandibular tumor was transferred to the intensive care unit with tracheostomy because of laryngospasm, upper respiratory tract, and laryngeal edema after extubation and was removed from the intensive care unit 1 d later without any complications during weaning. In our second patient, who underwent surgery for maxillary osteosarcoma, the mass was successfully removed, there was no bleeding in the mouth, and the possibility of laryngeal edema was low. No postoperative complications were noted.

Conclusion

Detailed preoperative evaluation and determination of anesthetic strategy are of great importance in patients with a predicted difficult airway. The condition of the patient's airway anatomy, deformities, and difficulties should be well-determined. When necessary, it should be confirmed using diagnostic methods. Depending on the situation, laryngoscopy and Spark plugs, videolaryngoscopy, fiberoptic bronchoscopy, and tracheostomy should be performed. Patients and their relatives should be informed in detail. In our two cases, preoperative preparation was performed appropriately, and fiberoptic tracheal intubation was performed safely. Although it has been discussed in recent years, we concluded that the use of fiberoptic bronchoscopy is the gold standard for providing airway patency before surgical intervention in the presence of a mass with a difficult airway, inadequate mouth opening, and obstructed access to the upper airway in cases where the passage of the endotracheal tube through the trachea becomes difficult, such as tracheal stenosis, and should be mandatory in anesthesia residency training.