Cough Peak Expiratory Flow Research Articles

The Impact of Nusinersen Treatment on Respiratory Function in Patients with Spinal Muscular Atrophy: A Systematic Review.

Background/Objectives: This systematic review evaluated the impact of nusinersen therapy on respiratory health and function in individuals with spinal muscular atrophy (SMA) and determined whether nusinersen improves pulmonary function, focusing on differences based on patient age and the timing of treatment initiation. Methods: A systematic search of PubMed, Ovid Medline, ScienceDirect, and Web of Science databases was conducted up to January 2024 in accordance with the PRISMA guidelines. Thirteen studies were included, comprising clinical trials, observational studies, and case series that focused on respiratory outcomes in SMA patients treated with nusinersen. The data on study design, participant characteristics, nusinersen intervention, respiratory outcomes, and adverse events were extracted. The Joanna Briggs Institute Critical Appraisal Tool was used to assess study quality. A narrative synthesis was conducted to address the heterogeneity of the studies. Results: This review found a general trend of improvement in pulmonary function, specifically in forced vital capacity (FVC), although the extent and duration of improvement varied across the studies. Peak cough flow (PCF) and peak expiratory flow (PEF) showed positive trends in some studies, although the results were not consistently significant. Respiratory function improvements were frequently observed, particularly in younger patients and those treated earlier. Conclusions: Nusinersen appears to enhance respiratory function and improve motor outcomes in SMA patients, especially with early treatment. However, further research is needed to fully understand its mechanisms and long-term effects on respiratory health in SMA.

Relationship between pulmonary, cough, and swallowing functions in individuals with amyotrophic lateral sclerosis.

Evaluations of pulmonary, cough, and swallow function are frequently performed to assess disease progression in amyotrophic lateral sclerosis (ALS), yet the relationship between these functions remains unknown. We therefore aimed to determine relationships between these measures in individuals with ALS. One hundred individuals with ALS underwent standardized tests: forced vital capacity (FVC), maximum expiratory/inspiratory pressure (MEP, MIP), voluntary cough peak expiratory flow (PEF), and videofluoroscopic swallow evaluation (VF). Duplicate raters completed independent, blinded ratings using the Dynamic Imaging Grade of Swallowing Toxicity (DIGEST) scale. Descriptives, Spearman's Rho correlations, Kruskal-Wallis analyses, and Pearson's chi-squared tests were completed. Mean and standard deviation across pulmonary and cough measures were FVC: 74.2% predicted (± 22.6), MEP: 91.6 cmH2O (± 46.4), MIP cmH2O: 61.1 (± 28.9), voluntary PEF: 352.7 L/min (± 141.6). DIGEST grades included: 0 (normal swallowing): 31%, 1 (mild dysphagia): 48%, 2 (moderate dysphagia): 10%, 3 (severe dysphagia): 10%, and 4 (life-threatening dysphagia): 1%. Positive correlations were observed: MEP-MIP: r = .76, MIP-PEF: r = .68, MEP-PEF: r = .61, MIP-FVC: r = .60, PEF-FVC: r = .49, and MEP-FVC: r = .46, p < .0001. MEP (p = .009) and PEF (p = .04) differed across DIGEST safety grades. Post hoc analyses revealed significant between group differences in MEP and PEF across DIGEST safety grades 0 versus 1 and grades 0 versus 3, (p < .05). In this cohort of individuals with ALS, pulmonary function, and voluntary cough were associated. Expiratory metrics (MEP, PEF) were diminished in individuals with unsafe swallowing, increasing their risk for effectively defending the airway.

Investigating the risk of reintubation by cough force assessment using cough peak expiratory flow: a single-center observational pilot study

BackgroundNo objective indicator exists for evaluating cough strength during extubation of tracheally intubated patients. This study aimed to determine whether cough peak expiratory flow (CPEF) can predict the risk of reintubation due to decreased cough strength.MethodsThis was a retrospective cohort study of patients who were admitted to our Emergency Intensive Care Unit between September 1, 2020 and August 31, 2021 and were under artificial ventilation management for ≥ 24 h. The patients were divided into two groups: successful extubation and reintubation groups, and the relationship between CPEF immediately before extubation and reintubation was investigated.ResultsSeventy-six patients were analyzed. In the univariate analysis, CPEF was significantly different between the successful extubation (90.7 ± 25.9 L/min) and reintubation (57.2 ± 6.4 L/min) groups (p < 0.001). In the multivariate analysis with age and duration of artificial ventilation as covariates, CPEF was significantly lower in the reintubation group (p < 0.01). The cutoff value of CPEF for reintubation according to the receiver operating characteristic curve was 60 L/min (area under the curve, 0.897; sensitivity, 78.5%; specificity, 90.9%; p < 0.01).ConclusionCPEF in tracheally intubated patients may be a useful indicator for predicting the risk of reintubation associated with decreased cough strength. The cutoff CPEF value for reintubation due to decreased cough strength was 60 L/min.

Sensorimotor Cough Dysfunction in Cerebellar Ataxias.

Cerebellar ataxias are neurological conditions with a high prevalence of aspiration pneumonia and dysphagia. Recent research shows that sensorimotor cough dysfunction is associated with airway invasion and dysphagia in other neurological conditions and may increase the risk of pneumonia. Therefore, this study aimed to characterize sensorimotor cough function and its relationship with ataxia severity. Thirty-seven participants with cerebellar ataxia completed voluntary and/or reflex cough testing. Ataxia severity was assessed using the Scale for the Assessment and Rating of Ataxia (SARA). Linear multilevel models revealed voluntary cough peak expiratory flow rate (PEFR) estimates of 2.61L/s and cough expired volume (CEV) estimates of 0.52L. Reflex PEFR (1.82L/s) and CEV (0.34L) estimates were lower than voluntary PEFR and CEV estimates. Variability was higher for reflex PEFR (15.74% coefficient of variation [CoV]) than voluntary PEFR (12.13% CoV). 46% of participants generated at least two, two-cough responses following presentations of reflex cough stimuli. There was a small inverse relationship between ataxia severity and voluntary PEFR (β = -0.05, 95% CI: -0.09 - -0.01L) and ataxia severity and voluntary CEV (β = -0.01, 95% CI: -0.02 - -0.004L/s). Relationships between reflex cough motor outcomes (PEFR β = 0.03, 95% CI: -0.007-0.07L/s; CEV β = 0.007, 95% CI: -0.004-0.02L) and ataxia severity were not statistically robust. Results indicate that voluntary and reflex cough sensorimotor dysfunction is present in cerebellar ataxias and that increased severity of ataxia symptoms may impact voluntary cough function.

The Effect of Pressure Changes During Mechanical Insufflation-Exsufflation on Respiratory and Airway Physiology

Respiratory muscle weakness can impair cough function, leading to lower respiratory tract infections. These infections are an important contributor to morbidity and mortality in patients with neuromuscular disease. Mechanical insufflation-exsufflation (MIE) is used to augment cough function in these patients. Although MIE is widely used, there are few data to advise on the optimal technique. Since the introduction of MIE, the recommended pressures to be delivered have increased. There are concerns regarding the use of higher pressures and their potential to cause lung derecruitment and upper airway closure. What is the impact of high-pressure MIE (HP-MIE) on lung recruitment, respiratory drive, upper airway flow, and patient comfort, compared with low-pressure MIE (LP-MIE), in patients with respiratory muscle weakness? Clinically stable patients using domiciliary MIE with respiratory muscle weakness secondary to Duchenne muscle dystrophy, spinal cord injury, or long-term tracheostomy ventilation received LP-MIE (30/-30cm H2O) and HP-MIE (60/-60cm H2O) in a random sequence. Lung recruitment, neural respiratory drive, and cough peak expiratory flow were measured throughout, and patients reported comfort and breathlessness following each intervention. A total of 29 patients (10 with Duchenne muscle dystrophy, eight with spinal cord injury, and 11 with long-term tracheostomy ventilation) were included in this study. HP-MIE augmented cough peak expiratory flow compared with LP-MIE (mean cough peak expiratory flow HP-MIE 228 ± 81 L/min vsLP-MIE 179 ± 67 L/min; P= .0001) without any significant change in lung recruitment, neural respiratory drive, or patient-reported breathlessness. However, in patients with more pronounced respiratory muscle weakness, HP-MIE resulted in an increased rate of upper airway closure and patient discomfort that may have an impact on clinical efficacy. HP-MIE did not lead to lung derecruitment or breathlessness compared with LP-MIE. However, it was poorly tolerated in individuals with advanced respiratory muscle weakness. HP-MIE generates more upper airway closure than LP-MIE, which may be missed if cough peak expiratory flow is used as the sole titration target. ClinicalTrials.gov; No.: NCT02753959; URL: www. gov.

Accumulated Secretions and Associated Aerodigestive Function in Patients With Dysphagia.

Accumulated pharyngo-laryngeal secretions are associated with dysphagia, aspiration, and poor health outcomes. Despite ongoing developments in the evaluation of pharyngo-laryngeal secretions, understanding of the underlying mechanisms is limited. Pathophysiology associated with accumulated secretions is needed to guide tailored, targeted treatment pathways. This study reports the prevalence of accumulated pharyngo-laryngeal secretions in a large acute care caseload and explores the relationship between secretions and aerodigestive function. Consecutive inpatients (N = 222) referred for flexible endoscopic evaluation of swallow (FEES) with suspected dysphagia following assessment by a speech-language pathologist were recruited (43% neurological, 22% neurosurgical, 20% critical care, 15% other), and 250 standardized FEES were completed (222 first FEES, 28 repeat FEES). The assessment protocol included secretion assessment using the New Zealand Secretion Scale (NZSS), pharyngeal squeeze maneuver, laryngeal motor and sensory assessment, Penetration-Aspiration Scale, and Yale Pharyngeal Residue Severity Rating Scale. Urge-to-clear ratings were collected during endoscopy. Cough peak expiratory flow and swallow frequency measures were also collected, as well as clinical outcomes at time of discharge. There was a high incidence of accumulated secretions, with 77% of inpatients having elevated NZSS (Mdn = 3, range: 0-7) and 37% with pooled laryngeal secretions. Accumulated secretions were associated with reduced swallow frequency, reduced laryngeal adductor reflex, impaired pharyngeal squeeze maneuver, and peak expiratory flow. NZSS scores also correlated with swallow measures (Penetration-Aspiration Scale and Yale Pharyngeal Residue Severity Rating Scale) and patient outcomes including diet recommendations at discharge and pneumonia during admission. This large study contributes to evidence associating both sensory and motor impairments with secretion accumulation and aspiration risk. Further exploration of the key physiological mechanisms contributing to accumulated secretions will serve as markers to provide proof of principle for targets for secretion management protocols. https://doi.org/10.23641/asha.24101667.

Cough Peak Flow Assessment Without Disconnection From the ICU Ventilator in Mechanically Ventilated Patients.

Because ICU ventilators incorporate flow velocity measurement, cough peak expiratory flow (CPF) can be assessed without disconnecting the patient from the ICU ventilator. Our goal was to estimate the correlation between CPF obtained with the built-in ventilator flow meter (ventilator CPF) and CPF obtained with an electronic portable handheld peak flow meter connected to the endotracheal tube. Cooperative mechanically ventilated patients who entered the weaning process and who were ventilated with pressure support < 15 cm H2O and PEEP < 9 cm H2O were eligible for the study. Their CPF measurements obtained on the extubation day were kept for analysis. We analyzed CPF obtained in 61 subjects. The mean ± SD value of ventilator CPF and peak flow meter CPF were 72.6 ± 27.5 L/min and 31.1 ± 13.4 L/min. The Pearson correlation coefficient was 0.63 (95% CI 0.45-0.76), P < .001. The ventilator CPF had an area under the receiver operating characteristic curve of 0.84 (95% CI 0.75-0.93) to predict a peak flow meter CPF < 35 L/min. Neither ventilator CPF nor peak flow meter CPF differed significantly between subjects who were or were not re-intubated within 72 h (n = 5) and failed to predict re-intubation at 72 h (area under the receiver operating characteristic curve of 0.64 [95% CI 0.46-0.82] and 0.47 [95% CI 0.22-0.74]). CPF measurements using a built-in ventilator flow meter were feasible in routine practice with cooperative ICU subjects who were intubated and correlated with CPF assessed by an electronic portable peak flow meter.

Evaluation of weaning parameters for weaning readiness from mechanical ventilation among elderly patients

Background: Numbers of elderly patients with acute respiratory failure continue to rise with increasing age of the general population worldwide. Ventilatory reserve decreases substantially with age as a result of multiple interrelated physiologic changes. Objective: This study aimed to evaluate the predictive value of conventional and composite weaning parameters among elderly patients. Methods: We conducted an observational prospective study among intubated patients ≥70 years old and readied for undergoing spontaneous breathing trial (SBT). Weaning parameters were recorded [heart rate, respiratory rate, tidal volume, minute ventilation (MV)] at 1 min, 30 min, and 2 hr after beginning of SBT. Cough peak expiratory flow (CPEF) and diaphragmatic thickness (DT) were also measured at 1 min after SBT. Weaning parameters were compared between the 2 patient groups (weaning success vs. weaning failure). Primary outcome was difference in weaning parameters between the 2 groups of patients. Results: All 48 subjects were enrolled. The mean (±SD) age was 80.2 (±6) years. Altogether, 38 patients (79.2%) were in the weaning success group and 10 patients (20.8%) in the weaning failure group. All baseline characteristics did not significantly differ between the 2 groups. While no difference was observed in other isolated weaning parameters between the 2 patient groups, we found that patients in the weaning success group had significantly lower MV than patients in the weaning failure group (8.3±1.8 vs. 9.9±2.5 L/min, p=0.025). Composite weaning parameters included MV/CPEF and MV/(CPEF x DT) increased predictive values for weaning failure than isolated MV with area under the receiver operating characteristics curves of 0.78, 0.80, and 0.72 respectively. The best cutoff point to predict weaning failure were MV ≥8.4 L/min, MV/CPEF ≥0.12, and MV/(CPEF x DT) ≥0.45 cm-1 Conclusion: MV was the only parameter associated with weaning failure among the elderly. Composite parameters demonstrated better predictive value for assessing weaning readiness among elderly patients.

A prospective examination of swallow and cough dysfunction after lung transplantation.

Swallow and cough dysfunction are possible surgical complications of lung transplantation (LT). We examined voluntary cough strength, sensorimotor reflexive cough integrity, and swallow-related respiratory rate (RR) across swallowing safety and aspiration response groups in recovering LT recipients. Forty-five LT recipients underwent flexible endoscopic evaluation of swallowing indexed by the validated Penetration Aspiration Scale. RR before and after a 3-ounce water drinking task was measured. Voluntary and reflexive cough screening were performed to index motor and sensory outcomes. T-tests, one-way ANOVAs, and chi-square (odds ratios) were used. 60% of patients exhibited laryngeal penetration (n=27) and 40% demonstrated tracheal aspiration (n=18); 72% (n=13) demonstrated silent aspiration. Baseline RR was higher in aspirators versus non-aspirators (26.5 vs. 22.6, p=0.04) and in silent aspirators compared to non-silent aspirators (27.9 vs. 20.7, p=0.01). RR change post-swallowing did not differ between aspiration response groups; however, it was significantly higher in aspirators compared to non-aspirators (3 vs. -2, p=0.02). Compared to non-silent aspirators, silent aspirators demonstrated reduced voluntary cough peak expiratory flow (PEF; 166 vs. 324 L/min, p=0.01). PEF, motor and urge to cough reflex cough ratings did not differ between aspirators and non-aspirators. Silent aspirators demonstrated a 7.5 times higher odds of failing reflex cough screening compared to non-silent aspirators (p=0.07). During the acute recovery period, all LT participants demonstrated some degree of unsafe swallowing and reduced voluntary cough strength. Silent aspirators exhibited elevated RR, reduced voluntary cough physiologic capacity to defend the airway, and a clinically distinguishable blunted motor response to reflex cough screening.

Predictors of Peak Expiratory Cough Flow in Individuals with Amyotrophic Lateral Sclerosis.

Dystussia is prevalent in individuals with amyotrophic lateral sclerosis (ALS), leading to a diminished physiologic capacity to effectively defend the airway. We aimed to identify predictors of peak expiratory cough flow rate in individuals with ALS. One hundred and thirty-four individuals with a confirmed diagnosis of ALS (El-Escorial criteria revised) completed the ALS Functional Rating Scale-Revised (ALSFRS-R) and underwent pulmonary function and cough spirometry testing. Pearson's correlation coefficients and hierarchical multiple regression modeling were conducted to determine predictors of voluntary cough peak expiratory flow rate (p < 0.05). The full model including age, bulbar disease, cough spirometry metrics, and respiratory parameters had a marginal R2=0.635, F (7, 126) = 30.241, p < 0.0005, adjusted R2 = 0.61. Maximum expiratory pressure, compression phase, and vital capacity did not contribute and were therefore removed (p < 0.05). The most parsimonious predictive model included age, bulbar disease, peak inspiratory flow rate and duration, peak expiratory rise time, and inspiratory pressure generation with a marginal R2 = 0.543. Although expiratory pressure generation has historically served as the therapeutic target to improve dystussia in ALS, the current dataset highlighted that the inability to quickly and forcefully inspire during the inspiratory phase of voluntary cough places patients at a mechanical disadvantage to generate subsequent high-velocity expiratory airflow to clear the airway. Thus, therapeutic training programs that include both inspiratory and expiratory strength targets may optimize airway clearance capacity in this challenging patient population.

Effect of prolonged mechanical ventilation on cough function and TRPV1 expression

Cough is a pivotal airway protective reflex, yet the effects of prolonged mechanical ventilation (PMV) on cough function are unknown. This study compared the cough function in subjects with PMV (≥ 21 days, n = 29) and those with short-term mechanical ventilation (SMV, ≤ 7 days, n = 27). Cough reflex sensitivity was measured by capsaicin provocation concentrations after extubation. The cough strength of respiratory muscles was assessed by involuntary cough peak expiratory flow (iCPEF). The mRNA expression of transient receptor potential vanilloid 1 (TRPV1), a cough sensor activated by capsaicin, in tracheal tissues was determined. We found that cough reflex sensitivity and iCPEF were significantly lower in the PMV group than in the SMV group. The tracheal expression of TRPV1 was similar in both groups, suggesting that changes in TRPV1 expression may not be a contributing factor. Our finding regarding the cough dysfunction after PMV highlights the need to implement effective airway clearance management and rehabilitation in this population.

Differences in voluntary and reflexive cough strength in individuals with amyotrophic lateral sclerosis and healthy adults.

Dystussia impacts the ability to protect the airway. Voluntary cough provides a metric of airway defense but differs from the reflexive response to aspiration during swallowing. Therefore, we evaluated relationships between voluntary and reflexive cough among individuals with amyotrophic lateral sclerosis (ALS) and a healthy cohort. Twenty-eight individuals with ALS and 26 healthy individuals completed voluntary and reflexive cough testing. Descriptive statistics, reliability, and paired t tests were conducted to evaluate differences in cough volume acceleration (CVA) and peak expiratory flow rate (PEFR) in voluntary vs reflexive cough. Compared with reflexive cough, voluntary CVA and PEFR were greater in individuals with ALS [t(27) = 4.83, P < .001 and t(27) = 8.69, P < .001] and the healthy cohort [t(21) = 5.91, P < .001 and t(21) = 12.26, P < .001], respectively. These findings hold important implications for the use and interpretation of voluntary peak cough flow during clinical swallowing evaluations.

The Role of Vocal Fold Bowing on Cough and Swallowing Dysfunction in Progressive Supranuclear Palsy.

Progressive supranuclear palsy (PSP) is a neurodegenerative disease which results in cough and swallowing dysfunction and aspiration pneumonia. Relationships among vocal fold atrophy, cough, and swallowing have been identified in related diseases, but remain unknown in PSP. This study examined: 1) the prevalence of vocal fold bowing in PSP, and 2) the influence of vocal fold bowing on cough and swallowing in PSP. Prospective Cohort Study. Twenty-three participants with PSP completed instrumental assessments of cough and swallowing. Vocal fold bowing (BI) and swallowing safety (PAS) was assessed using flexible laryngoscopy. Measures of cough effectiveness were obtained using spirometry. Statistical analyses were used to determine the frequency of mild-moderate (BI > 0) and severe (BI > 12.2) bowing, and to assess the influence of BI on PAS and cough effectiveness in PSP. Fifty-two percent (n = 12) of participants exhibited severe bowing while 48% (n = 11) exhibited mild-to-moderate bowing. Voluntary cough peak expiratory flow rate (P = .01), as well as reflex (P = .02) and voluntary (P = .005) cough volume acceleration were lower for participants with severe BI when compared to mild-to-moderate BI. However, BI did not influence PAS (P > .05). Findings from this study suggest that vocal fold bowing is highly prevalent in PSP and associated with reduced reflex and voluntary cough effectiveness. These findings provide insight into the pathophysiology of compromised airway protection in this patient population. Future studies should examine vocal fold atrophy as a treatment target for behavioral and medical intervention in PSP. 3 (Prospective Observational Study) Laryngoscope, 131:1217-1222, 2021.

Comparison of "cough peak expiratory flow measurement" and "cough strength measurement using the white card test" in extubation success: A randomized controlled trial.

Background:Failed extubation and subsequent re-intubation in ventilated patients can lead to many adverse consequences, including organizational and personal expenditures. Extubation decisions based on subjective methods are a major contributor to extubation failure. This study compared the effect of cough peak expiratory flow (PEF) measurement and cough strength measurement using the white card test (WCT) on extubation success.Materials and Methods:This randomized clinical trial was conducted in two groups in 2018 on 88 ventilated patients in intensive care units of Imam Reza Hospital in Mashhad, Iran. Ninety patients were divided into two groups of 45, but two were excluded from the white card group. The criteria established for extubation included PEF ≥60 L/min during coughing in the cough PEF group and noticing card humidity in the WCT group. In both groups, extubation success was determined as the sole outcome and was compared with the standard PEF and cough strength. The researcher who assessed the outcome and statistician were blinded about group allocation.Results:Extubation success was measured as 97.8% in the cough PEF group and 76.7% in the WCT group (P = 0.003) during the first 24 h. In the second 24 h, however, successful extubation was reported as 90.9% in the cough PEF group and 60.6% in the WCT group (P = 0.002).Conclusion:Using the cough PEF rate increases the likelihood of extubation success and reduces adverse effects, and is recommended to be used for extubation decision-making.

Dual Tasking Influences Cough Sensorimotor Outcomes in Healthy Young Adults.

Purpose Reflex cough is an essential airway protective mechanism that often occurs in the context of divided attention. The effect of divided attention on measures of reflexive cough airflow and sensitivity remains unknown. We present findings from a study testing the effects of divided attention (via a dual-task paradigm) on measures of reflex cough in healthy young adults. Method Volunteers (N = 20, age = 20-40 years) underwent 4 blocks of capsaicin-induced cough challenges. Within each block, capsaicin ranging from 0 to 200 μM was presented in a randomized order. Two blocks consisted of cough testing only (single task). During the other 2 blocks, participants counted tones while simultaneously undergoing cough testing (dual task). Measures of cough motor response, self-reported urge-to-cough, cough frequency, and cough airflow were collected. Results Participants coughed more in the single-task condition compared to the dual-task condition (p ≤ .001). Participants' urge-to-cough ratings were lower in the dual-task condition (x̅ = 2, "slight") compared to the single-task condition (x̅ = 3, "moderate"; p = .007). Participants' cough reflex sensitivity thresholds were significantly increased in the dual-task condition (p = .002). Cough peak expiratory flow rates did not change between the 2 conditions (p = .34). Conclusions Somatosensation of tussive stimuli changes during dual tasking. Abnormal cortical resource allocation may be a mechanism involved in silent aspiration.

Effect of Expiratory Muscle Strength Training on Swallowing and Cough Functions in Patients With Neurological Diseases: A Meta-analysis.

The aim of this review was to evaluate and summarize the results of published studies exploring the effects of expiratory muscle strength training on swallowing and cough functions in patients with neurological diseases. The study used Embase, PubMed, and the Cochrane Library as data sources. Randomized controlled trials or pretest/posttest studies of adults with neurological diseases were included. The data included basic population characteristics, penetration-aspiration scores, peak expiratory flow rate, cough volume acceleration, and maximum expiratory pressure. Ten studies were included in this meta-analysis. Compared with the control groups, expiratory muscle strength training in patients with neurological diseases significantly reduced the penetration-aspiration scores (risk ratio = -0.94, 95% confidence interval = 1.27 to -0.61, P < 0.01) but did not increase the voluntary cough peak expiratory flow rate (risk ratio = 0.57, 95% confidence interval = 0.62 to 1.77, P = 0.35), cough volume acceleration (risk ratio = 33.87, 95% confidence interval = 57.11 to 124.85, P = 0.47), or maximum expiratory pressure (risk ratio = 14.78, 95% confidence interval = 16.98 to 46.54, P = 0.36). Expiratory muscle strength training might improve swallowing function in patients with neurological diseases. However, conclusive evidence supporting the use of this approach in isolation for improving cough function is unavailable. Additional multicenter, randomized clinical trials performed using reliable and valid cough function outcome measures are required to explore the effects of expiratory muscle strength training on cough function.

Effect of Lee Silverman Voice Treatment (LSVT LOUD®) on swallowing and cough in Parkinson's disease: A pilot study

PurposeLee Silverman Voice Treatment (LSVT LOUD®) is an effective therapy for phonation in Parkinson's Disease (PD) but little is known about any additional spread of effects to swallowing and cough function. This pilot study examined the effect of LSVT LOUD on pharyngeal swallowing parameters and reflexive cough strength. MethodsTwenty participants (14 men, 6 women; mean 68years, SD3.5) with PD referred for LSVT LOUD with complaints of voice deterioration were recruited. Mean duration of PD was 6yrs., SD 3. Self-reported Eating Assessment Tool-10 scores ranging from 0 to 25 (normal<3). Prior to LSVT LOUD, 1-week post- and 6-months post-treatment, participants undertook a videofluoroscopic study of swallowing and aerodynamic measures of involuntary cough. ResultsAll participants completed the LSVT LOUD programme; 3 participants were lost to follow-up at 6-months. All participants made significant gains in average sound pressure level (dB SPL). Aspiration was not observed. Pharyngeal residue (p<0.05) and pharyngeal area at rest reduced (p<0.01) while maximal opening of pharyngoesophageal segment (PES) (p<0.05) and PES opening duration (p<0.05) significantly increased. There was a significant improvement in involuntary cough peak expiratory flow rate and peak expiratory flow rise time. All changes were maintained at 6-months. ConclusionLSVT LOUD demonstrates additional spread effects on pharyngoesophageal deglutitive function and involuntary cough effectiveness in people with mild PD referred with voice complaints. Consequently, LSVT LOUD has potential to provide additional benefits for swallowing safety and efficiency in this patient group.

Cough peak expiratory flow. assistance at extubation and outcomes

Cough strength predict extubation outcomes of patients who have passed a spontaneous breathing trial (SBT) (1,2).

Electrical Stimulation of Abdominal Muscles to Produce Cough in Spinal Cord Injury

Background. Surface electrical stimulation of the abdominal muscles, with electrodes placed in the posterolateral position, combined with a voluntary cough can assist clearance of airway secretions in individuals with high-level spinal cord injury (SCI). Objective. To determine whether an increase in stimulus intensity of the trains of electrical stimuli delivered to the expiratory muscles has an increasing effect on a stimulated voluntary cough and to determine at which stimulus intensity a plateau of cough peak expiratory flow occurs. Methods. In 7 healthy individuals with a SCI at and above C7, gastric pressure (Pga), esophageal pressure (Pes), peak expiratory cough flow (PEFcough), and expiratory volume were measured as participants coughed voluntarily with simultaneous trains of electrical stimuli delivered over the abdominal muscles (50 Hz, 1-s duration). The intensity of the stimulation was increased incrementally. Results: A plateau in PEFcough occurred in all 7 individuals at a mean of 211 ± 29 mA (range 120-360 mA). Peak values reached for Pga, Pes, and PEFcough were 83.0 ± 8.0 cm H2O, 66.1 ± 5.6 cm H2O, and 4.0 ± 0.4 l/s respectively. Conclusions. The plateau in expiratory cough flow that was associated with increasing expiratory pressures is indicative of dynamic airway compression. This suggests that the evoked cough will be effective in creating more turbulent airflow to further assist in dislodging mucus and secretions.

Benefit of triple-strap abdominal binder on voluntary cough in patients with spinal cord injury

A cross-sectional experimental study. The purpose of this study is to examine the benefit of elastic abdominal binders on voluntary cough in persons with spinal cord injury. Spinal rehabilitation unit in a teaching hospital. We measured voluntary cough peak expiratory flow rate (in 21 subjects with spinal cord injury, (18 tetraplegia, 3 paraplegia) under three conditions: without abdominal binder as the baseline, with single-strap abdominal binder and triple-strap abdominal binder. The results showed that the mean cough peak expiratory flow rate in all subjects without abdominal binder was 277.1 l per min. There was a significant increase in flow rate with the use of abdominal binders: 325.7 l per min with single-strap abdominal binder and 345.2 l per min with triple-strap abdominal binder (P<0.05, paired t-test). The mean cough peak expiratory flow rate in tetraplegic subjects using triple-strap abdominal binders was significantly higher compared with those using single-strap abdominal binders (322.1 l per min and 299.4 l per min, respectively). Abdominal binders can be used as an effective method to improve cough ability in spinal cord injured patients, with triple-strap abdominal binder achieving greater cough peak expiratory flows.