Peak Voluntary Cough Flow and Oropharyngeal Dysphagia as Risk Factors for Pneumonia

Objective To investigate the relationship between voluntary peak cough flow (PCF), oropharyngeal dysphagia, and pneumonia in patients who were evaluated with videofluoroscopic swallowing study (VFSS).Methods Patients who underwent both VFSS and PCF measurement on the same day were enrolled retrospectively (n=821). Pneumonia (n=138) and control (n=683) groups were assigned based on presence of pneumonia within 1 month from the date of VFSS assessment. In addition, sex, age (<65 and ≥65 years), preceding conditions, modified Barthel Index (MBI), Mini-Mental State Examination (MMSE), PCF value (<160, ≥160 and <270, and ≥270 L/min), and presence of aspiration/penetration on VFSS were reviewed.Results Pneumonia group was more likely to be male (n=108; 78.3%), ≥65 years (n=121; 87.7%), with neurodegenerative (n=25; 18.1%) or other miscellaneous diseases (n=50; 36.2%), and in poor functional level with lower value of MBI (39.1±26.59). However, MMSE was not significantly different in comparison to that of the control group. The pneumonia group was also more likely to have dysphagia (82.6%) and lower value of PCF (<160 L/min, 70.3%). In multivariable logistic regression analysis, male sex (odd ratio [OR]=6.62; 95% confidence interval [CI], 2.70–16.26), other miscellaneous diseases as preceding conditions (OR=2.52; 95% CI, 1.14–5.58), dysphagia (OR=3.82; 95% CI, 1.42–10.23), and PCF <160 L/min (OR=14.34; 95% CI, 1.84–111.60) were factors significantly related with pneumonia.Conclusion Impaired swallowing and coughing function showed an independent association with the development of pneumonia. Patients with PCF <160 L/min require more attention with lung care and should be encouraged with voluntary coughing strategy to prevent possible pulmonary complications.

Voluntary Cough Effectiveness and Airway Clearance in Neurodegenerative Disease

Purpose: Voluntary cough dysfunction is highly prevalent across multiple patient populations. Voluntary cough has been utilized as a screening tool for swallowing safety deficits and as a target for compensatory and exercise-based dysphagia management. However, it remains unclear whether voluntary cough dysfunction is associated with the ability to effectively clear the airway. Method: Individuals with neurodegenerative disorders performed same-day voluntary cough testing and flexible endoscopic evaluations of swallowing (FEES). Participants who were cued to cough after exhibiting penetration to the vocal folds and/or aspiration with thin liquids during FEES met inclusion criteria. One-hundred and twenty-three trials were blinded, and the amount of residue before and after a cued cough on FEES was measured with a visual analog scale. Linear and binomial mixed-effects models examined the relationship between cough airflow during voluntary cough testing and the proportion of residue expelled. Results: Peak expiratory flow rate ( p = .004) and cough expired volume from the entire epoch ( p = .029) were significantly associated with the proportion of aspiration expelled from the subglottis. Peak expiratory flow rate values of 3.00 L/s, 3.50 L/s, and 5.30 L/s provided high predicted probabilities that ≥ 25%, ≥ 50%, and ≥ 80% aspirate was expelled. Accounting for depth of aspiration significantly improved model fit ( p < .001). Conclusions: These findings suggest that voluntary cough airflow is associated with cough effectiveness to clear aspiration from the subglottis, although aspiration amount and depth may play an important role in this relationship. These findings provide further support for the clinical utility of voluntary cough in the management of dysphagia.

Cough-Inducing Method Using a Tartaric Acid Nebulizer for Patients with Silent Aspiration

The tartaric acid nebulizer is a well-known cough test to evaluate cough function. This study aimed to evaluate the effectiveness of a cough-inducing method using tartaric acid (CiTA). Patients with dysphagia examined by videofluoroscopic examination of swallowing (VF) at a single institution from May 2017 to August 2017 were included in this retrospective observational study. Although undergoing VF, patients who had aspirated without reflexively coughing or who had coughed insufficiently, were instructed to cough voluntarily. Patients who could not cough voluntarily or had expectorated insufficiently underwent the CiTA method. The rate of cough induction and the effectiveness of expectoration using the CiTA method were evaluated. One hundred fifty-four patients (mean age 69.2 ± 16.8 years) were evaluated. Eighty-seven patients aspirated during VF. Of those patients, 15 were able to expectorate via the cough reflex, 18 were able to expectorate with a voluntary cough, and 12 required suctioning for removal of aspirated material. The remaining 42 patients underwent the CiTA method. Thirty-eight patients (90.4%) could reflexively cough, and 30 (71.4%) could expectorate the aspirated material. This novel method, CiTA, was effective for cough induction in patients with dysphagia, especially for those with silent aspiration.

Risk and mitigation of aerosolisation from lung function testing: results from the AERATOR study

IntroductionLung function tests are fundamental diagnostic and monitoring tools for patients with respiratory symptoms. There is significant uncertainty around whether potentially infectious aerosol is produced during different lung function testing modalities; and limited data on possible mitigation strategies to reduce risk to staff and limit fallow time.MethodsHealthy volunteers were recruited in an ultraclean, laminar flow theatre and had standardised spirometry as per ERS/ATS guidance, as well as peak flow measurement and FENO assessment of airway inflammation. Aerosol emission was sampled minimum once each second using both an Aerodynamic Particle Sizer (APS) and Optical Particle Sizer (OPS), and compared to breathing, speaking and coughing. Mitigation strategies such as a peak flow viral filter and a CPET facemask (to mitigate induced coughing) were tested.Results33 healthy volunteers were recruited. Aerosol emission was highest in cough (1.61 particles/cm3/sample), followed by unfiltered peak flow (0.76 particles/cm3/sample). Filtered spirometry produced lower peak aerosol emission (0.11 particles/ cm3/sample) than that of a voluntary cough, and addition of a viral filter to the mouthpiece reduced peak flow aerosol emission to similar levels. The filter made little difference to recorded FEV peak flow values. Peak aerosol FENO measurement produced negligible aerosol. Reusable CPET masks with filter reduced aerosol emission when breathing, speaking, and coughing significantly.ConclusionsCompared to voluntary coughing, all lung function testing produced fewer aerosol particles. Filtered spirometry produces lower peak aerosol emission than peak voluntary coughing, and should not be deemed an aerosol generating procedure. The use of viral filters reduces aerosol emission in peak flow by > 10 times, and has little impact on recorded peak flow values. CPET masks are a useful option to reduce aerosol emission from induced coughing while performing spirometry.

Cough as a neurological sign: Does it worth it?

Cough is one of the most common complaints that lead patients to see a doctor. It is not only a basic respiratory sign but also an important neurological sign. There are 3 main types of cough: reflex cough (type I), voluntary cough (type II), and evoked cough (type III). Reflex cough sensitivity may be increased in many neurological disorders, such as space-occupying lesion of the brainstem, medullary lesions secondary to type I Chiari malformations, tics disorders such as Tourette’s syndrome, somatic cough, neurodegenerative disorders of the cerebellum, and chronic vagal neuropathy due to allergic and nonallergic diseases. On the other hand, cough sensitivity decreases in the cerebral hypoxia, cerebral hemispheric stroke with a brainstem shock, dementia due to Lewy body disease, Parkinson’s disease, amyotrophic lateral sclerosis, multiple sclerosis, and peripheral neuropathy such as hereditary sensory and autonomic neuropathy type IV, diabetic neuropathy, vitamin B12, and folate deficiency. The ear-cough reflex of Arnold’s nerve, syncopal cough, cough headache, opioid associated cough and cough-anal reflex are signs that can help in the diagnosis of underlying neurological disorders. The cough reflex test is a quick, easy, and inexpensive test that can be performed during the cranial nerve exam. In this article, we have discussed cough reflex testing and various neurological disorders that increase or decrease cough sensitivity.

Coughing as a potentially effective induction method of atrial tachycardia: a case report

Background Cough-induced atrial tachycardia (AT) is extremely rare and its electrical origin remains largely unknown. Atrial tachycardias triggered by pharyngeal stimulation, such as swallowing or speech, appears to be more common and the majority of them originate from the superior vena cava or right superior pulmonary vein (PV). Only one case of swallow-triggered AT with right inferior pulmonary vein (RIPV) origin has been reported to date. Case summary We present a case of a 41-year-old man with recurring episodes of AT in the daytime. He underwent electrophysiology study without sedation. Atrial tachycardia was not observed when the patient entered the examination room and could not be induced with conventional induction procedures. By having the patient cough periodically on purpose, transient AT with P-wave morphology similar to the clinical AT was consistently induced. Activation mapping of the AT revealed a centrifugal pattern with the earliest activity localized inside the RIPV. After successful radiofrequency isolation of the right PV, AT was no longer inducible. Discussion In the rare case of cough-induced AT originating from the RIPV, the proximity of the inferior right ganglionated plexi (GP) suggests the role of GP in triggering tachycardia. This is the first report that demonstrates voluntary cough was used to induce AT. In such cases that induction of AT is difficult using conventional methods, having the patient cough may be an effective induction method that is easy to attempt.

Effect of Brain Lesions on Voluntary Cough in Patients with Supratentorial Stroke: An Observational Study

Patients with stroke are known to manifest a decreased cough force, which is associated with an increased risk of aspiration. Specific brain lesions have been linked to impaired reflexive coughing. However, few studies have investigated whether specific stroke lesions are associated with impaired voluntary cough. Here, we studied the effects of stroke lesions on voluntary cough using voxel-based lesion-symptom mapping (VLSM). In this retrospective cross-sectional study, the peak cough flow was measured in patients who complained of weak cough (n = 39) after supratentorial lesions. Brain lesions were visualized via magnetic resonance imaging (MRI) at the onset of stroke. These lesions were studied using VLSM. The VLSM method with non-parametric mapping revealed that lesions in the sub-gyral frontal lobe and superior longitudinal and posterior corona radiata were associated with a weak cough flow. In addition, lesions in the inferior parietal and temporal lobes and both the superior and mid-temporal gyrus were associated with a weak peak cough flow during voluntary coughing. This study identified several brain lesions underlying impaired voluntary cough. The results might be useful in predicting those at risk of poor cough function and may improve the prognosis of patients at increased risk of respiratory complications after a stroke.