CC
This is a 57-year-old male with a history pertinent for a known broken tooth #19 who has been treated multiple times over the past 6 months with amoxicillin for periapical dental abscesses and pain. Over the past 48 hours, he has had increasing left-sided gingival and floor of mouth swelling extending to the bilateral sublingual space and submandibular space suggestive of Ludwig’s angina (see Ludwig’s angina in Chapter 23 ). As of the past few hours, he can no longer swallow. He has been carrying a stack of tissues to collect his drool. He has to sit upright to be comfortable breathing. It is painful to close his mouth completely or to open it farther. He is a choir tenor singer, but his voice now is very faint and sounds gravelly characteristic of dysphonia.
A concise and focused history is critical to timely recognition of a patient with an impending airway and appropriate management. Key facts include duration of relevant airway symptoms (the 3Ds [ d ysphagia, o d ynophagia, d ysphonia], trismus, and shortness of breath or stridor). Patients with rapidly progressive symptoms raise more clinical concern, as do those whose condition worsens with maximal medical treatment (antibiotics and steroids). The timing of steroids medications may affect the presentation. Intravenous (IV) dexamethasone (Decadron) takes 1 hour to have full effect and has a half-life of 4 hours, with possibility of refractory symptoms as the medication wears off.
Developing the differential diagnosis that guides treatment starts with the history. The most important questions to ask include those about their progression of symptoms and whether the patient is able to lie flat and tolerate secretions. Other relevant questions include when their last meal was and an assessment of allergies and previous reactions to anesthesia. During the initial evaluation, every patient should be counseled on their desires for the next steps and goals of care. Patients should be counseled if necessary on the possibility of needing intubation or a surgical airway for airway compromise.
PMHx/medications/allergies/SH/FH
The patient has a history of type 2 diabetes mellitus (well controlled) and hypertension. No other relevant history is reported. He had a cholecystectomy 5 years ago without complication. No previous surgeries of the neck or intubation related trauma was reported. He has no allergies or intolerances to anesthesia.
A targeted assessment of the past medical history is necessary to prepare for further management steps of the airway. Intubation history and prior surgeries are helpful to know how challenging the patient’s airway has been historically. If the patient has had a prior spinal fusion, this may limit neck mobility. Previous history of neck surgery is associated with altered anatomy and scar tissue, resulting in a more challenging surgical airway. Traumatic intubations are associated with subglottic stenosis.
Medical comorbidities affect the course of management. Diabetes is a reversible cause of immunosuppression; better glucose control is associated with an improved overall prognosis. Always screen for coagulopathies, malignant hyperthermia, and family history of anesthesia intolerances in all patients being assessed for airway concerns.
Examination
General. Well-developed, thin male in severe respiratory distress sitting upright. The patient has biphasic soft audible stridor. Intercostal retractions are noted. No supraclavicular retractions or nasal flaring.
Vital signs. Heart rate is 120 bpm, blood pressure is 168/94 mm Hg, respiratory rate is 27 beats per minute, temperature is 38.1°C, and oxygen saturation is 96% on room air.
Maxillofacial. Bilateral submandibular, sublingual, and submental cellulitis, tender to palpation, woody, warm, and erythematous (which are suggestive signs of Ludwig’s angina). There is notable level II submandibular swelling; however, the thyroid notch, cricoid, and trachea rings are palpable. The trachea is midline, and the cervical spine has full range of motion.
Intraoral. Oral examination is limited; there are two finger widths of trismus. The floor of the mouth is elevated, tender, and edematous. The tongue is large and protruding, and the uvula and soft palate are not visible (Mallampati class IV). Teeth #18, 19, and 30 are grossly carious.
Fiberoptic nasopharyngoscopy. Fig. 22.1 shows that there is diffuse edema along the base of the tongue, the esophageal inlet and arytenoid towers are visible, and the epiglottis and vocal cords cannot be visualized .
Assessment of sublingual swelling, trismus, and Mallampati score help in assessing challenges in accessing the airway. Based on this patient’s examination findings, his trismus and limited Mallampati score mean that it would be exceedingly challenging to align his oropharynx, pharynx, and glottic airway in one plane for direct visualization intubation. Classic signs of increased work of breathing include tachypnea, intercostal retractions, supraclavicular retractions, and nasal flaring. Late symptoms include hypoxemia, altered mental status, and lactic acidosis when compensation mechanisms start to fail. Drooling, biphasic stridor, and tripod positioning are signs of an impending airway obstruction. Stridor can be characterized as inspiratory, biphasic, and expiratory. Inspiratory stridor is usually more indicative of an upper airway supraglottic pathology than expiratory stridor, which can be more suggestive of intrathoracic tracheal pathology. Biphasic stridor is usually suggestive of a fixed airway obstruction, such as in this instance in which diffuse tissue edema along the sublingual space and base of the tongue is impinging on the glottic airway. Further airway evaluation can be performed with fiberoptic nasopharyngoscopy (visualizing the hypopharynx, base of the tongue, pharyngeal walls, epiglottis, and vocal cords) to determine airway patency and the extent of airway edema. The scope examination shown in Fig. 22.1 is worrisome because the glottis larynx cannot be visualized. However, if a patient is breathing, one must remember that there has to be a tenuous area of air passage. In patients with severe airway distress, the fiberoptic nasopharyngoscopy should be considered to be performed in the operating room (OR) because any manipulation of the airway may result in sudden compromise. This is especially the case if there is suspected epiglottitis ( Fig. 22.2 ). Landmarks for a surgical airway (thyroid notch, cricoid ring, and tracheal rings) should be palpated and examined in any patient with airway concerns to assess challenges one may encounter should a surgical airway be necessary ( Fig. 22.3 ).
Imaging. No computed tomography (CT) scan was able to be obtained. The patient was unable to tolerate lying flat on a stretcher.
In the setting of impending airway decline, any attempt to obtain imaging studies should be delayed until a secure airway has been established. To take a CT scan, the patient has to be able to tolerate lying flat for up to 5 minutes while managing secretions. Loss of an airway in the radiology suite, where personnel and backup airway equipment may not be available, can be devastating. For this reason, upon evaluation of the patient, the surgeon must quickly decide either to proceed to the OR, where optimal personnel and equipment for advanced airway intervention are available or, in a sudden emergency, proceed with immediate placement of a surgical airway in the emergency department (ED). In the most emergent scenarios, even transport to the OR can have perils, if there is the risk of loss of airway midway. Immediate intervention should be considered when the circumstances limit other options.
If the patient is deemed stable, with no immediate threat to airway obstruction, a panoramic radiograph (to evaluate possible odontogenic sources of infection) and a CT scan with contrast (to localize loculated areas of abscess formation and to assist in airway evaluation) can be obtained. Magnetic resonance imaging (MRI) is usually not the modality of choice because of concern for the patient remaining in the radiology suite for extended periods of time without monitoring. The activated magnet in the MRI suite also prevents immediate access to the patient for an emergency and access to airway equipment. For patients with contrast allergy, pretreatment regimens often require multiple hours of steroid treatments. Although there is an IV acceleration desensitization dose, the consequence of improperly treating a patient with a severe iodine contrast allergy may include angioedema, which could further complicate an already precarious airway. Securing or protecting the airway should always remain the priority.
A lateral neck radiograph is a study that can be obtained at the bedside. It can provide important information regarding the glottic airway (the width of the epiglottis should be <5 mm in an adult) and posterior airway space (prevertebral soft tissue should be <7 mm at the level of C3 and 20 mm at the level of C7). However, with the recent advent of fiberoptic nasopharyngoscopy and the use of CT, lateral cephalographs are rarely used today. Lateral cephalometric radiographs must also be properly obtained to be useful. Often, distortions of the airway shadow can occur because of twisting or poor positioning. As with any testing, before ordering, there should be adequate clinical suspicion for upper airway compromise warranting radiography evaluation; objective measures should also be used to evaluate the scans. The authors recommend measuring the narrowing of the airway shadow, thickening of the epiglottis, and comparing this with known values to evaluate any obtained neck radiographs.
