Effectiveness of Injection Laryngoplasty for Aspiration in Acute Iatrogenic Vocal Fold Paralysis: A Systematic Review

Abstract

Objective/Hypothesis: To review current evidence on effectiveness of injection laryngoplasty on aspiration outcomes in acute unilateral vocal fold paralysis.Study Design: Systematic review. Methods: A literature search was performed on MEDLINE, Embase, Scopus, and the Cochrane Library from inception of each database to May 2019. Inclusion criteria included case series, case-control studies, prospective cohort studies, and randomized controlled trials assessing the outcomes of early injection laryngoplasty on aspiration in unilateral vocal fold paralysis, in the acute setting. Only English articles with adult study populations were included. Two independent investigators screened all abstracts and manuscripts. Data on study design, patient demographics, interventions, and outcome measures were systematically extracted by both authors for included studies.Results: Fourteen case series studies comprising 582 patients were included. Results were not quantitatively synthesized due to the heterogeneity of outcome measures. Eleven studies reported that a majority (ranging 50%-100%) of patients in each respective study showed improvement in diet intake (progression from nil per os to oral) or Penetration-Aspiration Scale (PAS) scores after injection laryngoplasty. However, none of the investigations used a control group, and therefore, did not account for the possibility of improvement of function related to placebo or Hawthorne effects rather than attributed to intervention.Conclusions: No robust evidence was found to support injection laryngoplasty as an effective measure to improve aspiration outcomes in acute iatrogenic vocal fold paralysis. Current practices rely on empirical observations and scarce expert opinions. Further prospective investigations with controlled objective measures are necessary to definitively demonstrate the effectiveness of IL for aspiration management.

Aspiration prevention surgeries: a review

“…Vocal cord paralysis can result in chronic aspiration, particularly when combined with a laryngeal sensory deficit (e.g., a high vagal lesion) [65,66]. This can be prevented with injection medialization laryngoplasty [67][68][69][70][71][72].…”

Changes in Cough Airflow and Acoustics After Injection Laryngoplasty

“…In both, glottic competence appears to be an important factor, though the evidence is overall lacking. 5,17,19,20 The primary objective of our study was to test the hypothesis that restoring glottic competence with injection laryngoplasty may improve voluntary cough strength, as measured by cough PEFR. Though our data did not support this hypothesis, we found a statistically significant decrease in PEFRT and an increase in CVA, corresponding to an increase in cough effectiveness after injection laryngoplasty.…”

“…3,4 Though evidence is not robust and mostly based on uncontrolled case series, vocal fold medialization has been suggested as an intervention to prevent aspiration when glottic insufficiency is present. 5 The underlying mechanistic assumption is that improved glottic competence improves airway protection during a swallow, and may also improve cough strength, thereby reducing aspiration risk. Prospective investigation has however been noted to be lacking to support this intervention.…”

“…Prospective investigation has however been noted to be lacking to support this intervention. 5 The inverse relationship between cough strength and pneumonia risk is well established. Increased peak cough flow, as a measure of cough strength, has been associated with decreased pneumonia risk in patients with stroke, dysphagia, and head and neck radiation.…”

Infiltración temprana en la parálisis laríngea: evolución y factores pronósticos

“…Además, mejora la eficacia de la tos contribuyendo a evitar neumonias aspirativas. Pan et al [14] realizaron una revisión sistemática con 587 pacientes afectados de parálisis laringea y que sufrian aspiraciones. En este estudio se encontró que la infiltración mejoraba la puntuación en la escala Penetración-Aspiración (EPA), aunque ningún trabajo incluido contaba con grupo control.…”