Daily auricular stimulation with capsaicin ointment improved cough reflex sensitivity in elderly patients with dysphagia: a pilot study.

Background: In our previous study, a single auricular application of capsaicin ointment, but not placebo improved cough reflex in elderly patients with dysphagia.Aims/Objectives: In the present study, we examined whether daily auricular application of capsaicin ointment continued to improve cough reflex in similar patients.Material and methods: With a cotton swab, 0.025% capsaicin ointment was applied in each external auditory canal alternately once a day for 2 weeks. The cough reflex sensitivity was evaluated on videoendoscopy using a numerical score and inhalation cough challenge test using citric acid in elderly dysphagic inpatients.Results: After daily auricular application of capsaicin ointment for 2 weeks, the endoscopic score of glottal closure and cough reflexes significantly improved, and the citric acid cough threshold significantly decreased. There was a significant correlation between the endoscopic score and the citric acid cough threshold before and after daily capsaicin application in the patients.Conclusions: Daily auricular stimulation with capsaicin ointment for 2 weeks continued to improve the cough reflex sensitivity in elderly patients with dysphagia.Significance: Daily auricular stimulation with capsaicin ointment would be a safe and effective intervention to prevent pneumonia in elderly with a risk of aspiration.

Aural stimulation with capsaicin prevented pneumonia in dementia patients.

OBJECTIVE: In the present study, we examined the effects of daily application of capsaicin ointment to the external auditory canal for 6 months on the development of pneumonia in elderly dementia patients at high risk of aspiration. METHODS: Twenty-nine oldest-old bedridden dementia inpatients at high risk of aspiration were enrolled in the present study. Ointment containing 0.025% capsaicin was applied to each external auditory canal with a cotton swab alternatively once a day for 6 months. RESULTS: The incidence of pneumonia during the 6 months before the intervention was 1.80±0.37 in these patients. However, this incidence significantly decreased to 0.40±0.29 (p<0.01) during the 6 months of the alternative application of capsaicin ointment to each auditory canal. No adverse effect such as otalgia was observed. CONCLUSION: These findings suggest that daily long-term aural stimulation with capsaicin ointment enhanced the cough reflex via Arnold's ear-cough reflex as a glottis protective measure, resulting in the reduction of incidence of pneumonia in elderly dementia patients at high risk of aspiration. The daily aural stimulation with capsaicin ointment may be a safe and promising intervention to prevent aspiration pneumonia in elderly people, especially those who cannot undergo swallowing exercise.

Short-term pre-operative systemic administration with low-dose of steroid does not make a false-negative diagnosis of definite eosinophilic chronic rhinosinusitis after endoscopic sinus surgery.

According to JESREC criteria, definite eosinophilic chronic rhinosinusitis (ECRS) is postoperatively diagnosed based on over 70 eosinophils in high power magnification fields of the resected nasal polyps in patients with probable ECRS. Preoperative systemic administration with steroid is a standard practice, because it reduced intraoperative bleeding during endoscopic sinus surgery (ESS) in patients with ECRS. However, it was recently reported that systemic administration with steroid decreased the number of eosinophils in the nasal polyps, leading to a false negative diagnosis of definite ECRS. To overcome the risk, we have adopted short-term pre-operative systemic administration with low-dose of steroid and examined if our steroid administration makes a false-negative diagnosis. We performed a retrospective chart review of 42 patients with probable ECRS. Eleven patients were administered with 0.5 mg of bethametasone for 7 days before ESS, and other 31 patients were not administered. The average number of eosinophils in nasal polyps in patients who were administered with steroid was 188 ± 167, which was not different from 199 ± 149 in the patients who were not administered. These findings suggest that short-term preoperative administration with low-dose of steroid has few risk of a false-negative diagnosis of definite ECRS. J. Med. Invest. 66 : 233-236, August, 2019.

Aural stimulation with capsaicin ointment improved swallowing function in elderly patients with dysphagia: a randomized, placebo-controlled, double-blind, comparative study.

OBJECTIVE: The aim of this study was to assess whether aural stimulation with ointment containing capsaicin improves swallowing function in elderly patients with dysphagia. STUDY DESIGN: A randomized, placebo-controlled, double-blind, comparative study. SETTINGS: Secondary hospital. PATIENTS AND METHODS: Twenty elderly dysphagic patients with a history of cerebrovascular disorder or Parkinson's disease were randomly divided into two groups: 10 receiving aural stimulation with 0.025% capsaicin ointment and 10 stimulated with placebo. The ointments were applied to the external auditory canal with a cotton swab. Then, swallowing of a bolus of blue-dyed water was recorded using transnasal videoendoscopy, and the swallowing function was evaluated according to both endoscopic swallowing scoring and Sensory-Motor-Reflex-Clearance (SMRC) scale. RESULTS: The sum of endoscopic swallowing scores was significantly decreased 30 and 60 min after a single administration in patients treated with capsaicin, but not with placebo. Reflex score, but not Sensory, Motion and Clearance scores, of the SMRC scale was significantly increased 5, 30 and 60 min after single administration in patients treated with capsaicin, but not with placebo. No patient showed signs of adverse effects. CONCLUSION: As capsaicin is an agonist of the transient receptor potential vanilloid 1 (TRPV1), these findings suggest that improvement of the swallowing function, especially glottal closure and cough reflexes, in elderly dysphagic patients was due to TRPV1-mediated aural stimulation of vagal Arnold's nerve with capsaicin, but not with a nonspecific mechanical stimulation with a cotton swab.

[Aural Stimulation with Capsaicin Ointment Improved the Swallowing Function in Patients with Dysphagia: Evaluation by the SMRC Scale].

Cough and swallowing reflexes are important airway-protective mechanisms against aspiration. Angiotensin-converting enzyme (ACE) inhibitors, one of the side effects of which is cough, have been reported to reduce the incidence of aspiration pneumonia in hypertensive patients with stroke. ACE inhibitors have also been reported to improve the swallowing function in post-stroke patients. On the other hand, stimulation of the Arnold nerve, the auricular branch of the vagus, triggers the cough reflex (Arnold's ear-cough reflex). Capsaicin, an agonist of Transient Receptor Potential Vanilloid 1 (TRPV1), has been shown to activate the peripheral sensory C-fibers. Stimulation of the sensory branches of the vagus in the laryngotracheal mucosa with capsaicin induces the cough reflex and has been reported to improve the swallowing function in patients with dysphagia. In our previous study, we showed that aural stimulation of the Arnold nerve with 0.025% capsaicin ointment improved the swallowing function, as evaluated by the endoscopic swallowing score, in 26 patients with dysphagia. In the present study, the video images of swallowing recorded in the previous study were re-evaluated using the SMRC scale by an independent otolaryngologist who was blinded to the information about the patients and the endoscopic swallowing score. The SMRC scale is used to evaluate four aspects of the swallowing function: 1) Sensory: the initiation of the swallowing reflex as assessed by the white-out timing; 2) Motion: the ability to hold blue-dyed water in the oral cavity and induce laryngeal elevation; 3) Reflex: glottal closure and the cough reflex induced by touching the epiglottis or arytenoid with the endoscope; 4) Clearance: pharyngeal clearance of the blue-dyed water after swallowing. Accordingly, we demonstrated that a single application of capsaicin ointment to the external auditory canal of patients with dysphagia significantly improved the R, but not the S, M or C scores, and this effect lasted for 60 min. After repeated aural stimulation with the ointment for 7 days, the R score improved significantly in patients with severe dysphagia. The present findings suggest that stimulation of the Arnold's branch of the vagus in the external auditory canal with capsaicin improves the glottal closure and cough reflex in patients with dysphagia. Thus, aural stimulation with capsaicin represents a novel treatment for dysphagia. It is also suggested that repeated alternative aural stimulation with capsaicin for a week, rather than a single application, is needed to improve the swallowing function in patients with severe dysphagia. By the same mechanism as that underlying the effect of ACE inhibitors, aural stimulation with capsaicin may reduce the incidence of aspiration pneumonia in patients with dysphagia.

Signal shape feature for automatic snore and breathing sounds classification.

Snore analysis techniques have recently been developed for sleep studies. Most snore analysis techniques require reliable methods for the automatic classification of snore and breathing sounds in the sound recording. In this study we focus on this problem and propose an automated method to classify snore and breathing sounds based on the novel feature, 'positive/negative amplitude ratio (PNAR)', to measure the shape of the sound signal. The performance of the proposed method was evaluated using snore and breathing recordings (snore: 22,643 episodes and breathing: 4664 episodes) from 40 subjects. Receiver operating characteristic (ROC) analysis showed that the proposed method achieved 0.923 sensitivity with 0.918 specificity for snore and breathing sound classification on test data. PNAR has substantial potential as a feature in the front end of a non-contact snore/breathing-based technology for sleep studies.

Effects of aural stimulation with capsaicin ointment on swallowing function in elderly patients with non-obstructive dysphagia.

OBJECTIVE: In the present study, an attempt was made to examine the effects of aural stimulation with ointment containing capsaicin on swallowing function in order to develop a novel and safe treatment for non-obstructive dysphagia in elderly patients. DESIGN: A prospective pilot, non-blinded, non-controlled study with case series evaluating a new treatment. SETTING: Secondary hospitals. PATIENTS AND METHODS: The present study included 26 elderly patients with non-obstructive dysphagia. Ointment containing 0.025% capsaicin (0.5 g) was applied to the external auditory canal with a cotton swab under otoscope only once or once a day for 7 days before swallowing of a bolus of colored water (3 mL), which was recorded by transnasal videoendoscopy and evaluated according to the endoscopic swallowing score. RESULTS: After a single application of 0.025% capsaicin ointment to the right external auditory canal, the endoscopic swallowing score was significantly decreased, and this effect lasted for 60 minutes. After repeated applications of the ointment to each external auditory canal alternatively once a day for 7 days, the endoscopic swallowing score decreased significantly in patients with more severe non-obstructive dysphagia. Of the eight tube-fed patients of this group, three began direct swallowing exercises using jelly, which subsequently restored their oral food intake. CONCLUSION: These findings suggest that stimulation of the external auditory canal with ointment containing capsaicin improves swallowing function in elderly patients with non-obstructive dysphagia. By the same mechanism used by angiotensin-converting enzyme inhibitors to induce cough reflex, which has been shown to prevent aspiration pneumonia, aural stimulation with capsaicin may reduce the incidence of aspiration pneumonia in dysphagia patients via Arnold's ear-cough reflex stimulation.

Artificial neural networks for breathing and snoring episode detection in sleep sounds.

Obstructive sleep apnea (OSA) is a serious disorder characterized by intermittent events of upper airway collapse during sleep. Snoring is the most common nocturnal symptom of OSA. Almost all OSA patients snore, but not all snorers have the disease. Recently, researchers have attempted to develop automated snore analysis technology for the purpose of OSA diagnosis. These technologies commonly require, as the first step, the automated identification of snore/breathing episodes (SBE) in sleep sound recordings. Snore intensity may occupy a wide dynamic range (> 95 dB) spanning from the barely audible to loud sounds. Low-intensity SBE sounds are sometimes seen buried within the background noise floor, even in high-fidelity sound recordings made within a sleep laboratory. The complexity of SBE sounds makes it a challenging task to develop automated snore segmentation algorithms, especially in the presence of background noise. In this paper, we propose a fundamentally novel approach based on artificial neural network (ANN) technology to detect SBEs. Working on clinical data, we show that the proposed method can detect SBE at a sensitivity and specificity exceeding 0.892 and 0.874 respectively, even when the signal is completely buried in background noise (SNR < 0 dB). We compare the performance of the proposed technology with those of the existing methods (short-term energy, zero-crossing rates) and illustrate that the proposed method vastly outperforms conventional techniques.