The laryngeal adductor reflex (LAR) is characterised by brief vocal cord closure in response to laryngeal stimulation. It is important in swallowing physiology as it represents a mechanism for airway protection. The authors of this study examined whether the absence of the LAR in response to touch delivered to the arytenoids by the tip of an endoscope, was associated with aspiration and/or pneumonia. The sample consisted of inpatients of mixed aetiologies, consecutively referred for swallowing assessment to the ENT department in an urban teaching hospital. One of three participating otolaryngologists performed the LAR testing, followed by a modified protocol for endoscopic evaluation of swallowing (using two trials each of thin and thick fluid). The presence / absence of laryngeal penetration and aspiration was rated from recordings by trained raters blinded to the LAR status. Pneumonia during the patient hospital stay was determined by the presence of clinical symptoms diagnosed by the attending physician together with evidence of infiltrate on a chest X-ray. Complete results were obtained for 61 of 94 patients (64.9%). Results indicated that 40 patients (65.6%) demonstrated the LAR and 21 (34.4%) demonstrated no response.
No significant differences were found between the absence of the LAR and laryngeal penetration or aspiration on any of the swallowing tasks. However, 13 patients developed pneumonia during their hospital stay. Nine of these did not exhibit a LAR. The authors concluded that patients without intact laryngeal adductor reflex had 6.8 times increased odds of developing pneumonia compared with patients who exhibited a LAR.
Laryngeal sensitivity testing may be useful in highlighting patients at risk for pneumonia and could contribute to decision-making around clinical care of dysphagic patients.