OBJECTIVE: The purpose of this study is to evaluate all potential factors associated with laryngeal injury after endotracheal intubation in the pediatric population.
METHODS: A systematic literature search was conducted in Medline, Embase, Cochrane, web of science and Google scholar up to 20th of March 2023. We included all unique articles focusing on factors possibly associated with intubation-injury in pediatric patients. Two independent reviewers determined which articles were relevant by coming to a consensus, quality of evidence was rated using GRADE criteria. All articles were critically appraised according to the PRISMA guidelines. The articles were categorized in four outcome measures: post-extubation stridor, post-extubation upper airway obstruction (UAO) necessitating treatment, laryngeal injury found at laryngoscopy and a diagnosed laryngotracheal stenosis (LTS).
RESULTS: A total of 24 articles with a total of 15.520 patients were included. The incidence of post-extubation stridor varied between 1.0 and 30.3%, of post-extubation UAO necessitating treatment between 1.2 and 39.6%, of laryngeal injury found at laryngoscopy between 34.9 to 97.0% and of a diagnosed LTS between 0 and 11.1%. Although the literature is limited and quality of evidence very low, the level of sedation and gastro-esophageal reflux are the only confirmed associated factors with post-extubation laryngeal injury. The relation with age, weight, gender, duration of intubation, multiple intubations, traumatic intubation, tube size, absence of air leak and infection remain unresolved. The remaining factors are not associated with intubation injury.
CONCLUSIONS: We clarify the role of the potential factors associated with laryngeal injury after endotracheal intubation in the pediatric population.

Significant injuries from endotracheal intubation are exceedingly rare but can lead to life-threatening complications, such as pharyngeal perforation. This type of perforation can result in abscess formation and airway compromise. Risks for this complication include operator skill and intubation in emergent situations. This case report details a 59-year-old male who underwent elective septoplasty with bilateral nasal turbinate reduction. The procedure required general anesthesia induction and endotracheal intubation. He developed a gradually enlarging right-sided neck mass with associated fevers, neck pain, odynophagia, and dysphonia. He presented to the emergency department on postoperative day 5 and was diagnosed with a right-sided, prevertebral space abscess with airway mass effect secondary to pharyngeal perforation. He was admitted for operative management, intravenous antibiotics, and was successfully treated. While significant injury from endotracheal intubation is rare, it can result in infection and threaten airway patency. Emergency physicians must recognize pharyngeal perforation as a potential source of infection following instrumentation of the pharynx. This case has been reported to increase awareness of the potential for such injury.

This case report describes a right arytenoid dislocation after emergency fiberoptic nasotracheal intubation in a patient with angioedema. The patient returned to the emergency department multiple times with classic symptoms of arytenoid dislocation, complicated by resultant postinjury laryngeal edema and poorly controlled laryngopharyngeal reflux. The arytenoid injury was not initially recognized, which delayed treatment. Several months later, intraoperative assessment was done because of continued symptoms suspicious for laryngeal injury, resulting in a diagnosis of right cricoarytenoid joint fixation resulting from prior intubation trauma. Because of delayed diagnosis and treatment, severe cricoarytenoid joint scarring and fixation prevented repositioning of the arytenoid and improvement in laryngeal function. Discussion of this case includes a review of the anatomy and function of the arytenoid and cricoarytenoid joint, along with factors that increase and decrease joint stability and risk of injury. The etiology of arytenoid dislocation is described, along with suspected mechanisms of injury in anterior vs posterior and right vs left dislocations. Classic symptoms, the importance of early identification, and treatment options are also discussed.

Subglottic stenosis (SGS) is a challenging disease to diagnose in neonates. Long-range optical coherence tomography (OCT) is an optical imaging modality that has been described to image the subglottis in intubated neonates. A major challenge associated with OCT imaging is the lack of an automated method for image analysis and micrometry of large volumes of data that are acquired with each airway scan (1 to 2 Gb). We developed a tissue segmentation algorithm that identifies, measures, and conducts image analysis on tissue layers within the mucosa and submucosa and compared these automated tissue measurements with manual tracings. We noted small but statistically significant differences in thickness measurements of the mucosa and submucosa layers in the larynx (p  <  0.001), subglottis (p  =  0.015), and trachea (p  =  0.012). The automated algorithm was also shown to be over 8 times faster than the manual approach. Moderate Pearson correlations were found between different tissue texture parameters and the patient’s gestational age at birth, age in days, duration of intubation, and differences with age (mean age 17 days). Automated OCT data analysis is necessary in the diagnosis and monitoring of SGS, as it can provide vital information about the airway in real time and aid clinicians in making management decisions for intubated neonates.

We describe the clinical features of granulomas of the membranous vocal fold secondary to endotracheal intubation, bronchoscopy or esophagogastroduodenoscopy.
Retrospective case series.
Review of cases at a single tertiary institution with evaluation of patient demographic characteristics, time to presentation, time to treatment, and clinical outcomes.
Thirteen adult patients were identified with postintervention granuloma of the membranous vocal fold. All patients were female, with a mean age of 60 years (range, 28-81 years). None noted hoarseness prior to the intervention, and all noted significant hoarseness postoperatively. Conservative treatment with proton pump inhibitors and vocal rest was initially implemented in all patients. Four cases resolved without further intervention. Nine underwent surgical management because of airway symptoms, failure to improve, or patient request. One patient had injury to the contralateral vocal fold upon intubation. None experienced recurrence. Five had complete recovery of voice postoperatively, four did not.
Iatrogenic granulomas of the membranous vocal fold after intubation or other upper airway instrumentation are rare complications presenting in the early postprocedure period with worsening hoarseness. Initial conservative treatment may be sufficient to yield resolution, and surgical treatment is effective for those failing medical management. Permanent voice damage may result from the original injury.
4 Laryngoscope, 129:441-447, 2019.

Current imaging modalities lack the necessary resolution to diagnose subglottic stenosis. The aim of this study was to use optical coherence tomography (OCT) to evaluate nascent subglottic mucosal injury and characterize mucosal thickness and structural changes using texture analysis in a simulated intubation rabbit model.
Prospective animal study in rabbits.
Three-centimeter-long sections of endotracheal tubes (ETT) were endoscopically placed in the subglottis and proximal trachea of New Zealand White rabbits (n = 10) and secured via suture. OCT imaging and conventional endoscopic video was performed just prior to ETT segment placement (day 0), immediately after tube removal (day 7), and 1 week later (day 14). OCT images were analyzed for airway wall thickness and textural properties.
Endoscopy and histology of intubated rabbits showed a range of normal to edematous tissue, which correlated with OCT images. The mean airway mucosal wall thickness measured using OCT was 336.4 μm (day 0), 391.3 μm (day 7), and 420.4 μm (day 14), with significant differences between day 0 and day 14 (P = .002). Significance was found for correlation and homogeneity texture features across all time points (P < .05).
OCT is a minimally invasive endoscopic imaging modality capable of monitoring progression of subglottic mucosal injury. This study is the first to evaluate mucosal injury during simulated intubation using serial OCT imaging and texture analysis. OCT and texture analysis have the potential for early detection of subglottic mucosal injury, which could lead to better management of the neonatal airway and limit the progression to stenosis.
NA Laryngoscope, 127:64-69, 2017.

To demonstrate that reconstructive transoral laser microsurgical (R-TLM) techniques can be used for the treatment of symptomatic laryngeal posterior glottic web-based stenosis (PGWS) in a large cohort of patients utilizing a postcricoid mucosal advancement flap (PCMAF).
Retrospective cohort review.
A consecutive series of patients with PGWS who underwent R-TLM using a PCMAF were reviewed for outcomes. After laser excision of the PGWS scar and mobilization of fixed cricoarytenoid joints, a PCMAF was raised using microinstruments and a scanning free-beam CO2 laser. The flap was advanced and attached over the scar bed using a technique with multiple novel features that make it easy to adopt.
Fifty-two patients were treated. Of the cases, 42.3% had a tracheostomy at presentation with grade II to IV PGWS, and 46% of cases had grade III to IV PGWS. In all cases, R-TLM was the only treatment approach. No open reconstructions were performed. No airway stents were used. Patients without tracheostomy, regardless of the grade of stenosis, did not require a tracheostomy to undergo this operation. All tracheostomy patients were successfully decannulated. All patients without a tracheostomy had significant improvement of their respiratory symptoms on the Dyspnea Index (mean Δ = 14.75, P value <.01).
RTLM using the PCMAF is a feasible, safe, and effective alternative to open approaches for airway reconstruction for PGWS. This novel transoral technique includes a much simpler endoscopic suturing alternative to knot tying among other new features. It is reproducible and reliable for laryngologists familiar with laryngeal microsurgery.
4. Laryngoscope, 127:685-690, 2017.

BACKGROUND: Subglottic edema and acquired subglottic stenosis are potentially airway-compromising sequelae in neonates following endotracheal intubation. At present, no imaging modality is capable of in vivo diagnosis of subepithelial airway wall pathology as signs of intubation-related injury.
OBJECTIVE: To use Fourier domain long-range optical coherence tomography (LR-OCT) to acquire micrometer-resolution images of the airway wall of intubated neonates in a neonatal intensive care unit setting and to analyze images for histopathology and airway wall thickness.
METHODS: LR-OCT of the neonatal laryngotracheal airway was performed a total of 94 times on 72 subjects (age, 1-175 d; total intubation, 1-104 d). LR-OCT images of the airway wall were analyzed in MATLAB. Medical records were reviewed retrospectively for extubation outcome.
RESULTS: Backward stepwise regression analysis demonstrated a statistically significant association between log(duration of intubation) and both laryngeal (P < 0.001; multiple r(2) = 0.44) and subglottic (P < 0.001; multiple r(2) = 0.55) airway wall thickness. Subjects with positive histopathology on LR-OCT images had a higher likelihood of extubation failure (odds ratio, 5.9; P = 0.007). Longer intubation time was found to be significantly associated with extubation failure.
CONCLUSIONS: LR-OCT allows for high-resolution evaluation and measurement of the airway wall in intubated neonates. Our data demonstrate a positive correlation between laryngeal and subglottic wall thickness and duration of intubation, suggestive of progressive soft tissue injury. LR-OCT may ultimately aid in the early diagnosis of postintubation subglottic injury and help reduce the incidences of failed extubation caused by subglottic edema or acquired subglottic stenosis in neonates. Clinical trial registered with www.clinicaltrials.gov (NCT 00544427).