Irritable Larynx and Chronic Cough and Paradoxical VF Dysfunction CD661 1. Lecture 12 - Irritable Larynx, Chronic Cough and Paradoxical Vocal Fold Dysfunction (PVFD)

Irritable Larynx Syndrome (ILS) Definition : “Hyperkinetic laryngeal dysfunction resulting from a variety of specific causes and is a response to a definitive triggering stimulus that be may internal or external” Can cause laryngeal muscle spasms, airway obstruction, episodes of cough when a specific cause is not evident. Sometimes referred to as laryngospasm, PVFM or VCD 2. Irritable larynx, chronic cough and PVFD are debilitating disorders. ILS is defined as a hyperkinetic laryngeal dysfunction resulting from a variety of causes and is a response to an internal or external stimulus.

Possible Etiology Brainstem control of laryngeal sensory-motor processes have been altered such that abnormal muscle activity and spasms result in response to normal sensory stimuli Possibly due to : Viral infection in CNS Damaged sensory nerves ‘regrow’ and branch in an abnormal manner Emotional states and defense reactions (PAG) Asthma-like upper airway reactions 3. ILS theory describes how neural-plastic changes affect the laryngeal CNS control network to produce a hyper-irritable ‘spasm ready’ state in the peripheral laryngopharyngeal muscles. The transition from a rest state of ‘spasm ready ‘ to ILS symptoms requires a trigger that is sometimes exacerbated by muscle tone modulators such as psychological stress or postural factors making the laryngopharynx more susceptible to spasm in the presence of specific triggers. The theoretical mechanisms if ILS symptom development have been inferred from research and theory in chronic pain and central sensitivity syndromes (CSS). In ILS brainstem control of laryngeal sensory motor processes has been altered so that abnormal muscle tension and spasm occur in response to normal levels of stimuli. A number of CNS pathologic processes may result in chronic laryngeal motor stimulation and elevated sensory irritability. Neural plasticity may affect the way that laryngeal motor and related systems react to sensations or thoughts through one of several mechanisms; 1. Development of new afferent inputs to the CNS after previous input is withdrawn due to peripheral nerve injury. This results in a change in responses to sensory input. 2. Viral infection may cause altered central sensory motor control and heightened laryngeal reactivity due to alterations in periqueductal gray (PAG) nuclei. 3. Hypersensitivity due to chronically hypertonic laryngeal muscles associated with unexpressed negative emotions mediated by sensory motivation controlling structures in the PAG and reticular formation. 4. Parasympathetic hyperactivity reactions in the upper airway to chronic sensory stimuli such as olfactory stimuli or refluxate from the stomach. ILS appears to falls into a broad syndrome group that that includes other central sensitivity syndromes.

Demographics & Descriptive Data 85% are female w/ average age 50 21% on leave or disability due to ILS Dominate symptom in 50% - laryngospasm Other symptoms - chronic cough 13%, dysphonia 9% , of those w/ laryngospasm, 50% reported MTD, 42% chronic cough and 11% globus sensation 75% present w/ extralaryngeal muscle tension MOST COMMON TRIGGERS: airborne irritants, especially perfumes; reflux and postural changes resulting in reflux; voice use; exercise ; emotional stressors 4. Regarding etiology, similarities have been reported between ILS pathophysiology and that of other chronic conditions associated with central nervous system sensitivity syndromes. Primary symptoms of ILS include chronic cough, laryngospasm (larynx spasms and VFs close; also called PVFD), muscle tension dysphonia and globus pharyngeus. Diagnostic inclusion criteria include symptoms related to hypertonicity/hyperkinetic activity in the laryngeal and related muscle systems; visible and palpable evidence of laryngeal paralaryngeal muscle misuse; evidence of specific triggering stimuli. Exclusion criteria include anatomical laryngeal /pharyngeal/esophageal pathologies that account for peripheral hyper-sensitivity and laryngeal symptoms; definitive neurological disease known to cause ILS symptoms; prexisting psychiatric diagnosis.

Treatment Level 2 - Reprogram maladaptive responses by Level 1- Minimize sensory stimuli & minimize exposure Level 2 - Reprogram maladaptive responses by decr. muscle tension, utilizing pursed lip breathing Level 3 – Reprogram CNS via motor relearning and centrally active medications Neuropsychotropic Medication : Tricylic antidepressants, Baclofen, Gabapentin, Botox into TA muscle, Seratonin reuptake inhibitors Employ Cognitive behavioral tx to decrease anxiety Desensitization therapy 5. ILS treatment should focus n a comprehensive approach to minimize disability, reduce distress, improve general health and reduce the use of medical resources. These goals are generally addressed at three primary levels of treatment objectives. Level 1 is to minimize sensory stimuli acting as triggers both internal (reflux) and external (odors etc) and maximize reflux management if applicable. Level 2 is to reprogram the habituated laryngeal motor response , desensitize and use principles of motor relearning. Level 3 capitalizes on neural plasticity to reprogram the central nervous system.

Paradoxical VF Dysfunction (Motion) Upper airway disorder that results in episodes of partial to complete VF adduction, primarily during inhalation Disorder of laryngeal airway protection that can be remediated via behavioral intervention Is not a disorder of vocal quality Can occur while awake or asleep but can also be triggered by exercise Can start suddenly or gradually Often misdiagnosed as asthma 6. Paradoxical VF dysfunction is a debilitating disorder that results in VF closure during inhalation. It is remediable via behavioral intervention.

PVFD Etiology Etiology can vary but falls into 1 of three groups 1. exposure to environmental irritants 2. psychogenic cause (less common) 3. neurological cause (very rare) Occurs in both males and females across all ages 5% prevalence in elite athletes Differential dx - differentiate from asthma, laryngeal pathology, panic attack, laryngeal edema secondary to allergic reaction Pulmonary exam 7. The etiology of PFVD is still unconfirmed but is believed to possibly fall into one of 3 categories; exposure to environmental irritants, psychogenic causes (stress, anxiety) and neurological causes. It is important to differentially diagnose PVFD from asthma and other disorders and the patient should have a full pulmonary assessment to rule out pulmonary disease. Many persons with PVFD have concurrent medical conditions such as panic attack and asthma (40-60% of patients). The patient should also have a thorough pulmonary exam to rule out pulmonary disease.

Development of PVFD Typically after repeated or a single sever exposure to an irritant which triggers an upper airway protective response Irritants may be intrinsic (internal) such as reflux or extrinsic (external )such as environmental such as fumes, smoke, perfume etc. Individual patient triggers must be discerned and the specific symptoms of imminent attack must be determined. Triggers must be avoided until breath recovery training is resolves the problem 8. PVFD typically evolves after repeated or a single serve exposure to an irritant. The irritant may be intrinsic such as reflux or extrinsic such as fumes, smoke and perfume odors. For therapy to be successful, the patient’s triggers must be accurately identified and early signs and symptoms of the attack determined if behavioral therapy is to be successful.

Case History Interview Careful and detailed interview is essential Client explains exact nature of breathing events Don’t lead the client towards a conclusion 9. A careful and detailed case history is essential for adequate treatment planning. Be careful not to lead the client in anyway or suggest answers to your questions.

Interview Questions Do you have trouble inhaling, exhaling or both ? Do make noise when this happens ? Can you imitate the noise? Do you feel tightness anywhere ? In chest, throat or both ? What triggers the event? How often do the attacks happen? How long do they last? What do you do for them? What works, doesn’t work? Do you use an inhaler? Does it work? How long does it take to work? Have you ever passed out, been to EW or hospitalized as a result of an episode? 10. These specific questions can be used to discern the exact nature of the patient’s breathing difficulty in order to create an appropriate behavioral plan.

Goals of Behavioral intervention Train breathing recovery methods Three components of breathing recovery training 1. body awareness training via progressive tightening – relaxing activities 2. training lower abdominal / rib cage expansion during inhalation 3. rapid deep nasal sniff followed by complete exhalation or oral straw sip inhalation followed by complete exhalation using a front sibilant or fricative sound (s or f) All 3 steps should be practiced while asymptomatic so patient can use step 3 easily when breathing attack is imminent 11. The goal of both medical and behavioral treatment is complete resolution of the problem. Athletes present a specific sub-population because their PVFD occurs at predictable time. Thus the unique feature of each sport will require specific adaptations, such as taking reflux meds before practice or competition, changing meal times, and training breathing recovery exs. in a sport specific manner rather than when sedentary.