Oral surgery with nasotracheal intubation in a patient with ectodermal dysplasia

Summary

Ectodermal dysplasias are a rare group of heritable disorders involving the ectodermal derivatives with only a few published reports involving its anaesthetic management. We present the case of a 16‐year‐old boy with ectodermal dysplasia presented for elective oral surgery under general anaesthesia with a surgeon preference for nasotracheal intubation to provide adequate surgical exposure. The patient had successful nasal flexible bronchoscopic intubation despite challenging tracheal intubation conditions. We summarise previous case reports and discuss anaesthetic considerations in ectodermal dysplasia , including reduced mucus production in the respiratory tract, laryngeal incompetence, potential for difficult tracheal intubation and hyperthermia from reduced or absent sweat glands.

Introduction

Ectodermal dysplasias are a rare group of more than 170 heritable disorders with variable inheritance pattern involving the ectodermal derivatives, classically defined as nails, teeth, hair and eccrine sweat glands. Ectodermal dysplasia has been categorised into hidrotic and anhidrotic (or hypohidrotic) forms. [1] The facial features of patients with ectodermal dysplasia may include a saddle‐shaped nose; frontal bossing; prominent supraorbital ridges; sparse and dry hair; maxillary hypoplasia; microstomia; prominent pouting lips; small conical shaped teeth; missing teeth; and cleft lip and cleft palate [2, 3, 4, 5, 6, 7]. The nails may be dysplastic and temperature regulation may be impaired due to inadequate sweating [2, 3, 4, 5, 7]. Characteristics of patients’ respiratory and gastrointestinal systems may include decreased mucus production; frequent respiratory infections; otitis media; bronchitis; dysphagia; and laryngeal incompetence [3, 4, 7]. Patients with ectodermal dysplasia may also have atopic disorders or immunodeficiency [5, 7]. Some forms of ectodermal dysplasia are associated with tumours, including non‐Hodgkin’s Lymphoma; hamartoma and squamous‐cell carcinoma [5].

A literature review revealed only a few reports of the anaesthetic management of patients with ectodermal dysplasia (Appendix S1). One letter to the editor described severe epistaxis following nasotracheal intubation in a 5‐year‐old with ectodermal dysplasia, resulting in oxygen desaturation and requiring bronchoscopy for clot removal [8]. We report on the anaesthetic management and successful nasotracheal intubation of a patient with ectodermal dysplasia who presented for oral surgery, despite challenging tracheal intubation conditions.

Report

A 16‐year‐old boy (73 kg; 180 cm) with ectodermal dysplasia presented for elective dental extractions with placement of eruption chains to secondary teeth in the mandible. His mother and sister also had ectodermal dysplasia. He had no other significant medical history except for abnormally draining tear ducts and a remote history of epistaxis. His past surgical history included bilateral myringotomy with eustachian tube placement and nasolacrimal duct drainage, without anaesthetic complications. He and his mother denied any history of increased sweating, recent respiratory infection or family history of malignant hyperthermia. On physical examination, he was noted to have dry, coarse skin and a Mallampati 3 airway with adequate mouth opening and thyromental distance. The anaesthesia team preferred the oral route to tracheal intubation rather than a nasal route because of concern that the patient's tracheal may be been difficult to intubate , as well as concerns regarding the patient’s dry, fragile respiratory mucosa. The surgeon, however, requested a nasal tracheal intubation route for adequate surgical exposure. Before bringing the patient to the operating room, various sizes of nasal Ring‐Adair‐Elwyn (RAE) tracheal tubes (Covidien, Minneapolis, MN, USA) were warmed and softened, and laryngeal masks (LMA Unique™; Teleflex Medical, Wayne, PA, USA) of various sizes were available. A 7.0‐mm internal diameter (ID) nasal RAE tracheal tube was ultimately chosen. A smaller nasal RAE tracheal tube was not chosen due to concerns for insufficient length and anticipated head movement during the surgery.

Pre‐operatively, the patient received intravenous midazolam 2 mg as an anxiolytic, as well as oral paracetamol 1 g, celecoxib 400 mg and gabapentin 400 mg to aid in peri‐operative pain management. Oxymetazoline 0.05% nasal spray was administered into both nostrils. He was brought to the operating room where pulse oximetry, electrocardiography, non‐invasive blood pressure and temperature monitoring were established. After the patient was pre‐oxygenated with 100% inspired oxygen, intravenous fentanyl 1.4 µg.kg⁻¹ was administered and anaesthesia was induced with propofol 2 mg.kg⁻¹. After confirming the ability to mask ventilate the patient, rocuronium 0.6 mg.kg⁻¹was administered. With the neck in a neutral position, a nasal flexible bronchoscopic intubation with a lubricated nasal RAE tracheal tube was performed with ease, attempting to avoid any direct contact between the tip of the scope and the airway mucosa. No bleeding was observed in the nasal passages. The epiglottis and larynx were noted to be small and pale (Fig. 1). General anaesthesia was maintained with sevoflurane in oxygen and air at 2 l.min⁻¹ with F_IO₂ of 0.6; heat‐moisture exchangers were utilised. Dexamethasone 4 mg and ondansetron 4 mg were given as antiemetics.

Figure 1.

At the glottic level, nasal flexible bronchoscopic intubation demonstrating a pale, small epiglottis.

At the beginning of the procedure, the patient’s axillary temperature was 34.1°C. After turning on a lower body forced‐air warming blanket for one and a half hours, the patient’s temperature increased to 35.6°C.

The surgical procedure was completed in 70 min. After the initial dose of rocuronium, no additional neuromuscular blockade was administered. Residual neuromuscular blockade was reversed with neostigmine and glycopyrrolate and the patient met extubation criteria. We carefully extubated the patient’s trachea, as removal of the nasotracheal tube can potentially injure the fragile nasal mucosa. The patient was then transferred to the recovery room in stable condition and discharged to home that day.

Discussion

This case report describes the successful nasotracheal intubation of a patient with ectodermal dysplasia, despite challenging tracheal intubation characteristics, and we highlight the anaesthetic considerations for this population. The care of these patients warrants careful attention during the pre‐operative, intra‐operative and postoperative phases of anaesthesia.

During the pre‐operative evaluation of patients with ectodermal dysplasia, a recent respiratory tract infection should be carefully excluded as decreased mucus production predisposes these patients to frequent respiratory infections and bronchitis. Elective surgery should be rescheduled for patients with a recent upper respiratory infection. Frequent coughing with meals may indicate laryngeal incompetence. Furthermore, examinations revealing maxillary hypoplasia, high‐arched palate or conical peg‐shaped teeth may be suggestive of difficult tracheal intubation.

Difficult airway equipment should be prepared and readily available. Orotracheal intubation is preferred over the nasal route given patients’ small saddle‐shaped noses as well as dry, fragile nasal mucosa from decreased or absent mucous glands, all of which predisposes patients to potential mucosal trauma, bleeding and infection. Ishii et al. reported a patient with ectodermal dysplasia who had a severe epistaxis after a conventional blind naso tracheal intubation. [8] To mitigate this risk, we planned for a continuous view by performing a nasal flexible bronchoscopic intubation with adequate lubrication and application of a topical nasal vasoconstrictor. We contemplated using a 6.5‐mm ID nasal RAE tracheal tube, yet we chose a 7.0‐mm ID nasal RAE tracheal tube due to concerns of inadequate length and subsequent risk of accidental intra‐operative extubation. The 7.0‐mm ID nasal RAE tracheal tube also provided a larger orifice to suction possible thick secretions from the tracheal tube. If a nasotracheal intubation was unable to be achieved, orotracheal intubation would have been performed. Interestingly, a pale small epiglottis was noted during tracheal intubation possibly as a result of hypoplastic mucous glands from ectodermal dysplasia.

Humidification of the airway by a heated humidifier or heat‐moisture exchanger should be considered and the tracheal tube cuff should be inflated using a minimal leak technique. Maintenance of normothermia is important, aided by continuous temperature monitoring. Docquier et al. presented a case of a child with anhidrotic ectodermal dysplasia and multiminicore myopathy; of interest, multiminicore myopathy and malignant hyperthermia are not associated with ectodermal dysplasia (Supplementary Material S1)[9, 10]. Since patients with ectodermal dysplasia often develop hyperthermia due to hypohidrosis, this may confound the diagnosis of malignant hyperthermia, which should be considered in the differential diagnosis for hyperthermia. In our case, after warming the patient with a forced‐air blanket the patient’s temperature rapidly increased by 1.5°C in 70 min. In most patients given general anaesthesia, the body temperature declines, especially in the first 30–60 min from internal core‐to‐peripheral redistribution of body heat. However, this phenomenon was not well observed in our presented case. This suggested an atypical heat and temperature response for a patient with ectodermal dysplasia due to inadequate hidrosis.

During emergence from anaesthesia, the tracheal tube should be gently removed to minimise the risk of nasal turbinate injury. Awake tracheal extubation should be considered due to potential laryngeal incompetency and subsequent aspiration. Postoperatively, patients should be closely monitored as applicable for aspiration, respiratory infection and hyperthermia.

The characteristics of patients with ectodermal dysplasia present anaesthetic challenges. A heightened awareness of the characteristics of these patients and the challenges they pose will aid in the development of an anaesthetic plan for the peri‐operative period (Table 1).

Table 1.

Summary of anaesthetic considerations for patients with ectodermal dysplasia.

Pre‐operatively evaluate for recent infection, in particular: otitis media; respiratory tract infection; bronchitis; and pneumonia. Develop a conscientious airway management plan. Small saddle‐shaped nose; hypoplasia of the maxilla; high‐arched palate; conical peg‐shaped teeth; missing teeth; and dry mucosa can increase the risk of bleeding; infection; trauma; and difficult tracheal intubation. Consider flexible bronchoscopic intubation using a well‐lubricated smaller tracheal tube and the application of mucosal vasoconstrictor for nasal approaches. Carefully monitor and regulate temperature peri‐operatively given increased risk for hyperthermia due to inadequate hidrosis. Consider an airway humidification strategy. Consider the potential for laryngeal incompetency and subsequent aspiration upon emergence and extubation.

Supporting information

Appendix S1. Summary of case reports and anaesthetic key points associated with ectodermal dysplasia.