Complications associated with nasotracheal intubation and proposal of simple countermeasure

To the Editor, Nasotracheal intubation is a widely used technique in anaesthesia management for procedures including oropharyngeal, dental, and maxillofacial surgeries[1-3]. It provides an uninhibited access to the mouth and plays an important role when dealing with difficult airways[4-6]. It is also used in patients with cervical spine instability owing to injury[7] or in patients with a cervical spine fixation owing to a disease or previous operation[8]. Moreover, it is selected for patients who require prolonged intubation for intensive care[9]. However, nasotracheal intubation may lead to certain complications, with epistaxis being the most common. Epistaxis generally occurs due to damage of the Kiesselbach's plexus in the anterior part of the nasal septum[10-12] where branches from several arteries, including branches of the ophthalmic, maxillary, and facial arteries, anastomose to form a vascular plexus. To avoid this complication, the tracheal tube should be inserted into the nasal cavity such that its bevel tip comes to the lateral side of naris. However, if the bleeding occurs on insertion of the tube, the nasotracheal intubation should be completed to chiefly protect the airway and also to tamponade the bleeding point. Risk of sinusitis is another disadvantage associated with nasotracheal intubation[13]. Sinusitis can induce oedema around the opening of the maxillary sinus. Mucosal oedema in the nasopharynx can also result in the middle-ear problem. Superficial necrosis of the nasal ala is another common complication associated with the nasotracheal intubation[3,9,14,15]. Several measures have been suggested to avoid this necrosis problem [15-18]; however, these measures cannot always be applied in paediatric patients as their naris do not provide enough space for them. Nasotracheal intubation has also been reported to cause bacteraemia owing to abrasion of the nasal mucosa [19,20]. The nasotracheal intubation-related carriage of bacteria into the trachea should be also avoided. It is reported that prior treatment of nostrils and anterior nasal septum with mupirocin is effective to avoid this complication[21,22]. However, the cheapest and easiest countermeasure to avoid such a complication during the nasotracheal intubation for inducing anaesthesia involves removal of the nasal dirt from the tip of the tracheal tube; in short, the tracheal tube should be pulled out with the aid of Magill forceps through the patient's mouth and the dirt should be wiped with a clean cotton (Figure 1). Additionally, dirt from the pharynx should be completely sucked under direct vision laryngoscope if required, before advancing the tracheal tube into the larynx. Once the tube tip and the pharynx are cleaned, the tube should be pulled again into the oral cavity by pulling the proximal side of the tube near the patient's nostril. Subsequently, the tube tip can be advanced into the larynx with the aid of Magill forceps. This series of treatment does not take longer than 10 seconds to perform once the anaesthesiologist and nurse anaesthetist get accustomed to it, thereby preventing an extreme fall in the peripheral capillary oxygen saturation (SpO2), even in paediatric patients. If the SpO2 value goes below the permissible range during the procedure, the patient can be easily ventilated by connecting the ventilation hose from the anaesthesia machine to the tracheal tube thereby completely closing the nose and mouth of patient (Figure 2), whereas some anaesthesiologists believe that the tracheal tube should be completely drawn from the patient's nose again to ventilate the patient with a mask On the other hand, some anaesthesiologists advance the tracheal tube further into the trachea in almost a panic condition, even when they have recognised the nose dirt on its tip (Figure 3), to prevent SpO2 fall, especially in paediatric patients. Therefore, knowledge of the ventilation technique via the tracheal tube inserted in the patient's nostril can be of great advantage while performing nasotracheal intubation. It can allow anaesthesiologists to calmly pull out the tip of tracheal tube using Magill forceps through the patient's mouth, when they recognise the nose dirt on it, to advance a cleaned tracheal tube into the trachea, even in paediatric patients. In conclusion, we suggest a simple countermeasure to avoid possible complications of nasotracheal intubation. It involves movement of a cleaned tracheal tube into the trachea of patient. Moreover, we suggest a possible ventilation technique in case the SpO2 falls beyond the permissible range during the nasotracheal intubation.