32.3.1 Employing the Mnemonics Suggested in Chapter 1, Does This Patient Have a Difficult Airway?
On MOANS-guided airway evaluation (see Section 1.6.1), you gain no confidence that you will be able to ventilate this patient using bag-mask-ventilation (BMV) when it becomes necessary. If her neck cannot be extended, a mask seal will be difficult. She is obese and the decrease in compliance may hinder BMV.
Employing LEMON (see Section 1.6.2) to assess the difficulty associated with laryngoscopy and intubation reveals that the look of this patient suggests difficulty. When you attempt to evaluate the geometry of her upper airway, you are unable to assess the volume of her mandibular space. This is particularly problematic in a person with Down syndrome (DS) in which the initial impression is that the tongue is relatively large for the volume of the mouth. You also have no idea where her larynx is relative to the base of her tongue. You are unable to evaluate a Mallampatti and get some idea as to airway access. Additionally, she is obese and you are unable to evaluate the degree of neck mobility.
The mnemonic for difficulties in using extraglottic devices (EGDs) is RODS (see Section 1.6.3). Whether there is restricted mouth opening or not is unknown. There does not appear to be any upper airway obstruction and the airway is neither distorted nor disrupted. As mentioned earlier, she is obese and the decreased compliance (stiff) may militate against successful ventilation with an EGD.
Finally, the patient should be assessed for a potentially difficult cricothyrotomy using the mnemonic SHORT (see Section 1.6.4). There is no history of prior anterior neck surgery, hematoma, or other overlying process that masks the anatomy. However, she is obese, and in addition, one is unable to ascertain whether access to the anterior neck is possible. There is no history or evidence of radiation or tumor.
In summary, she has a potentially difficult airway and is not a candidate for a rapid-sequence induction, even though with a stomach potentially full of blood that would ordinarily be the preferred technique.
32.3.2 What Other Airway Concerns Do You Have in Patients with DS?
An increased incidence of subglottic stenosis in DS patients is well known.1-4 This has been attributed, at least in part, to the increased incidence of regurgitation and aspiration in these patients during infancy and early childhood.1 Therefore, these patients may require an endotracheal tube that is one to two sizes smaller than the standard size appropriate for the patient's age. In addition, the DS patient is predisposed to obstructive sleep apnea due to a relatively narrow nasopharynx and large tongue.5,6
C-spine subluxation is also seen in these patients and may be of concern in airway management.7 Presently there is no consensus of opinion with respect to the need for preoperative radiological evaluation of the cervical spine for subluxation for patients with DS.
32.3.3 What Are the Airway Management Options?
This patient gives every indication that the management of her airway will be difficult. However, the more pressing problem is deciding how to pharmacologically manage her behavior without compromising her ability to maintain ventilation and oxygenation, to permit either an IV start and/or to gain control of the airway in a controlled fashion that minimizes the risk of aspiration.
Ideally, one would like to identify a preferable airway technique (Plan A), and two alternative methods (Plans B and C). However, with the limited airway evaluation, the most appropriate method chosen must have the least chance of producing apnea, aspiration, or a requirement for rapid action. In addition, the presence of copious amounts of blood in the airway is likely to render indirect visualization techniques (endoscopes, video laryngoscopes, optical stylets) to be of limited use. This really leaves one primary option for consideration: sedation and awake intubation employing a laryngoscope.
Plans B and C will likely include an EGD and the surgeon should be prepared to perform an immediate surgical airway if asked (a double set-up). One would be wise to consider the immediate availability of a lightwand (eg, Trachlight™) if the airway practitioner is sufficiently skilled in its use (see Chapter 11).