Persistent Features of Laryngeal Injury Following Endotracheal Intubation: A Systematic Review

This systematic review examined (i) prevalence, severity, and impact of persistent post-extubation laryngeal injury beyond hospital discharge and (ii) differences in persistent laryngeal injury between COVID-19 and non-COVID-19 populations. The review was completed following PRISMA-2020 guidelines. Four databases (PubMed, CINHAL complete, EMBASE, Web of Science) were searched (inception to March 2021). Screening, full text review and data extraction were completed by two reviewers. Primary outcomes were swallow, voice and cough and airway measures obtained after hospital discharge. Quality assessment was measured using Downs & Black Tool and Johanna Briggs Institute Checklist for Cohort Studies. Meta-analysis was not completed due to study heterogeneity. Six cohort studies were included. Total number of participants across the included studies was 436. ICU admission diagnoses included respiratory disease 46% (COVID-19 and non-COVID-19), sepsis 14%, non-sepsis-related organ dysfunction 9%, general medical 11%, general surgical 10%, trauma 2%, ENT 0.6% and other not specified by authors 7%. Outcomes were obtained between 2 and 60 months post hospital discharge. Assessment methods included endoscopic evaluation, clinician ratings and patient-reported outcomes. Persistent features of laryngeal injury identified were airway abnormalities (18.9-27%), dysphonia (13.2-60%) and dysphagia (23-33%). Persistent laryngeal injury was associated with ICU length of stay, respiratory diagnosis and tracheostomy. Study quality ranged from poor-good. This is the first systematic review to examine post-extubation laryngeal injury beyond hospital discharge. Significant gaps in the literature were identified. Given the impact on clinical and patient outcomes, large scale, well-designed research is needed to guide post-ICU service delivery.