Management and Discussion of COVID-19 Related Tracheal Stenosis: A Single Center Retrospective Review

Figures & data

Table 1 Cases 1–6 Including Age, Sex, Days Under Care, Comorbidities

Case 1	47	Woman	58 days (18 I, 40 T)	Type 2 Diabetes Mellitus, Diabetic Ketoacidosis
Case 2	63	Man	14 days (14 I, 0 T)	Hypertension, end-stage renal disease
Case 3	45	Woman	66 days (13 I, 53 T)	Crohn’s disease on immunosuppressant therapy
Case 4	42	Man	8 days (8 I, 0 T)	Type 2 diabetes mellitus, diabetic ketoacidosis
Case 5	34	Woman	67 days (25 I, 42 T)	Severe obesity, type 2 diabetes mellitus, eosinophilic asthma
Case 6	65	Woman	8 days (8 I, 0 T)	Chronic obstructive pulmonary disease, type 2 diabetes mellitus, end-stage renal disease

Abbreviations: I, intubated; T, trached.

Table 2 Pathogenesis of Disease Burden and Prevention Taken Respectively

Pathogenesis	Prevention
COVID-19 induces a profound pro-inflammatory cascade referred to as a cytokine storm leading to tissue damage.^Citation1	Tocilizumab, an interleukin-6 inhibitor, may be used to reduce inflammation.^Citation1
The cuff of the endotracheal tube inflates and deflates daily for weeks. Moreover, the rigid tube is moved and assessed for cuff leaks. The constant external pressure eventually causes tracheal irritation and fibrosis via biomechanical stress.^Citation2 Persistent mechanical tension also leads to defective TGF-β signaling and enhances the fibrotic cascade.	Prolonged tracheal irritation may be alleviated with a tracheostomy tube if it can be done safely (with minimal risk of aerosol cross-infection). This may be an effective tool to facilitate ventilator weaning.^Citation3
Repeated intubations may be needed if the first attempt is not successful, especially in patients with different anatomic variants. They cause repeated physical trauma to the trachea.	Video-assisted laryngoscopy may successfully reduce the number of intubation attempts compared to direct laryngoscopy and minimize risk of esophageal intubation.^Citation4
The cuff of the endotracheal tube tightly seals the endotracheal tube to the trachea constantly exerting pressure and stopping circulation to the tracheal wall causing local ischemia and eventually scar formation. Due to the lack of blood flow, tissue damage continues.^Citation5	The pressure of the cuff of the endotracheal tube should be reduced to allow for local blood flow and replenish nutrients to the area.^Citation6 Cuff pressures should be inflated to 20 to 30 mm H2O. Pressures greater than 30 mm H2O have been associated with venous stasis, which sets forth the pathway to tracheal stenosis. Oversized tube diameters should be avoided. In obese patients, consider tracheostomy tubes with an extended proximal limb rather than a larger diameter tube.^Citation7 Control of comorbidities is also important, as patients with underlying diabetes mellitus and cardiovascular disease may have microvascular changes that put them at increased risk for tissue ischemia.
The growth of granulation leads to delayed airway stenosis and causes patients to come to the hospital about a month after they are discharged home after being intubated and in the intensive care unit for weeks.	Patient education on signs of tracheal stenosis before discharge with the instruction to seek medical attention quickly may expedite the diagnosis of TS. An intralesional steroid injection, topical mitomycin C or 5-fluorouracil/triamcinolone, may prevent severe tracheal stenosis due to their anti-fibrotic and anti-inflammatory properties.^Citation8,Citation9
Gastroesophageal reflux may cause and exacerbate laryngeal damage.^Citation10	Both lifestyle and pharmacologic interventions to prevent gastroesophageal reflux may help to reduce the risk of developing tracheal stenosis. In the critical care setting, it is important to consider prevention against tracheal stenosis in addition to stress ulcer formation as an indication for prophylactic acid suppression.

Figure 1 Grade 3, concentric, corkscrew-type stenosis seen on CT chest (A) and pre-dilation bronchoscopy (B). Post-dilation bronchoscopy reveals airway patency (C).

Figure 2 Grade 3, complex corkscrew-type stenosis which extended 3 tracheal rings seen on CT chest (A) and pre-dilation bronchoscopy (B). Post-dilation bronchoscopy reveals airway patency (C).

Figure 3 Grade 3, concentric, corkscrew-type stenosis which extended at least 2 tracheal rings seen on CT chest (A) and pre-dilation bronchoscopy (B). Post-dilation bronchoscopy reveals airway patency (C).

Figure 4 Grade 3, complex, concentric stenosis seen on CT chest (A) and pre-dilation bronchoscopy (B). Post-procedure bronchoscopy reveals airway patency with silicone studded hourglass stent in place (C).

Figure 5 Grade 3, oval, corkscrew-type stenosis which extended 2 tracheal rings seen on CT chest (A) and pre-dilation bronchoscopy (B). Post-dilation bronchoscopy reveals airway patency (C).

Figure 6 Grade 3, concentric stenosis seen on CT chest (A) and pre-dilation bronchoscopy (B). Post dilation bronchoscopy reveals airway patency (C).

Figure 7 Classification grading demonstrating various levels of stenosis of the lumen based on the Meyer’s Cotton system.¹⁵

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