Evaluation of Translaryngeal Percutaneous Arytenoid Lateralization (TPAL) in dogs with experimentally created laryngeal paralysis

Description and evaluation of a novel transoral endoscopic arytenopexy in canine cadavers

OBJECTIVE

To describe the transoral endoscopic arytenopexy (TEA) and evaluate its effects on the rima glottis area (RGA) and laryngeal epiglottic-glottic seal (LEGS). We hypothesize the TEA will be a feasible surgical technique and the TEA will provide a significant increase in RGA with minimal change to the LEGS.

STUDY DESIGN

Canine cadaveric model.

ANIMALS

Fifteen medium- to large-breed canine cadavers.

METHODS

Endoscopic photos of the larynx were taken with the epiglottis open for baseline RGA measurement and closed for baseline measurement of exposed RGA and LEGS. A custom endoscopic gag port (EGP) facilitated the TEA, performed by suturing the lateral aspect of the left arytenoid soft tissues to adjacent pharyngeal wall across the piriform recess. Endoscopic photos were repeated to measure changes in RGA and LEGS. A computerized planimetric analysis program was used to calculate baseline RGA and LEGS. The RGA was reported in % change from baseline. The LEGS was reported as intact or altered. A nonparametric Wilcoxon signed-rank test was used to compare baseline to post-TEA RGA.

RESULTS

The mean baseline RGA was 0.52 ± 0.28 cm³ and mean post-TEA RGA was 0.78 ± 0.37 cm³ (p-value < .0001). The LEGS remained intact post-TEA in all cadavers.

CONCLUSIONS

The TEA was technically feasible and resulted in an increase in RGA while maintaining the LEGS.

CLINICAL SIGNIFICANCE

The TEA may provide a minimally invasive addition to the established techniques for reducing airway resistance while minimizing the impact on the LEGS.

Effect of doxepin on quality of life in Labradors with laryngeal paralysis: A double-blinded, randomized, placebo-controlled trial

Background

Laryngeal paralysis commonly affects older Labrador retrievers. Currently, dogs with severe disease require surgical intervention, most commonly arytenoid lateralization. Anecdotally, doxepin has been proposed to help dogs with laryngeal paralysis.

Hypothesis

Doxepin will improve quality of life measures assessed by owners of Labrador retrievers with laryngeal paralysis not requiring emergency surgery.

Animals

Twenty‐two Labrador retrievers with laryngeal paralysis.

Methods

Dogs were randomized to receive doxepin (3‐5 mg/kg q12h PO) or placebo for 28 days. Owners completed quality‐of‐life assessments before and after completing the study. Data were compared between groups using Rank‐Sum tests or Fisher's exact tests.

Results

The 2 groups of dogs did not differ at baseline except for owner‐perceived degree of ataxia (owners of dogs receiving doxepin considered them more ataxic than owners of dogs receiving placebo). After 28 days, owner‐assessed quality of life measures did not differ between dogs receiving doxepin or placebo (dogs worsening: doxepin = 2, placebo = 1; dogs unchanged: doxepin = 6, placebo = 7; dogs improved: doxepin = 4, placebo = 2; P = .84). Dogs receiving placebo had a greater improvement in client‐assessed overall health than dogs receiving doxepin (mean ranks: doxepin = 4.36, placebo = 6.64; P = .04). The study was terminated at this interim analysis.

Conclusions and Clinical Importance

Doxepin did not appear to improve any measures of owner‐assessed quality of life in Labrador retrievers with laryngeal paralysis.