Maximal Respiratory Pressure Reference Values for Hopi Children Ages 4-13.

Anthropometric variables will influence maximal respiratory pressure (MRP) values. Since significant variations exist in pulmonary nomograms amongst different races, it is important that tribe specific tables of normal maximal inspiratory pressures (MIP) and maximal expiratory pressures (MEP) be developed. To date, MRP prediction equations do not exist for Hopi children. PURPOSE: The purpose of this study was to develop MRP reference values and prediction equations for Hopi children in the ages 4-13 years. METHODS: A cross-sectional study was undertaken with 288 healthy children (125 male, 163 female), a 36% representative population of all the Hopi Native children attending Hopi Tribal Elementary Schools in Arizona. MIP and MEP values were measured. RESULTS: Age and the inverse of body mass were consistently significant predictors of the MRPs for both sexes. Predictions using the derived Hopi equations were significantly different (p≤0.001) than those using the equations for Navajo and Caucasian youth across both sexes, making it important for this population to have specific formulae to provide more accurate reference values. CONCLUSIONS: These data were collected from the children of Hopi ancestry resulting in MIP and MEP reference equations which should be used when measuring MIP and MEP in these children ages 4-13 years.

Reproducibility of Maximum Respiratory Pressure Assessment: A Systematic Review and Meta-analysis.

BACKGROUND: Accurate assessment of maximum respiratory pressure is vital when tracking disease progression and devising treatment strategies. Previous studies indicate a learning effect when undertaking maximum respiratory pressure measurements. The extent of this learning effect and methodologies undertaken to mitigate this learning effect have not been investigated systematically. RESEARCH QUESTION: What is the magnitude of improvements in maximum respiratory pressure in response to respiratory muscle warm-up protocols and repeated measures of maximum respiratory pressure in healthy individuals and clinical populations? METHODS: A comprehensive search of electronic databases was undertaken during August 2021 for studies examining the intrarater reliability of maximum inspiratory or expiratory pressure, or both, studies developing a protocol or an intervention to obtain maximum values, and studies analyzing the reliability of repeated maneuvers in a single testing session in healthy individuals and clinical populations. Included articles were analyzed critically using two appraisal tools. Standardized mean differences with 95% CIs were calculated and corrected for the sample size as a measure of the magnitude of change in maximum respiratory pressure outcomes. RESULTS: Of the 1,969 articles retrieved, 32 were included in the meta-analysis. Eighteen studies included healthy individuals and 14 studies included individuals with chronic medical conditions. The overall effect of inspiratory muscle warm-up protocols was higher (effects size [ES], 0.40; 95% CI, 0.17-0.63) in comparison with single testing session studies (ES, 0.20; 95% CI, 0.05-0.35) and studies performing repeated testing sessions of maximum respiratory pressure (ES, 0.14; 95% CI, 0.07-022). INTERPRETATION: Inspiratory muscles warm-up procedures induce higher increases in maximum inspiratory pressure in comparison with single and repeated testing sessions of maximum respiratory pressure in healthy individuals. Warm-up protocols are more effective to obtain the maximum performance of inspiratory muscles in one testing session in comparison with other methods. TRIAL REGISTRY: PROSPERO; No.: CRD42022304591; URL: https://www.crd.york.ac.uk/prospero/.

Effects of a new respiratory muscle training device in community-dwelling elderly men: an open-label, randomized, non-inferiority trial.

BACKGROUND: Respiratory muscle training (RMT) has various clinical benefits in older adults; however, the low adherence to training remains a challenging issue. The present study aimed to confirm the efficacy of a new device that combines inspiratory muscle training and a positive expiratory pressure (IMT/PEP) compared to that of a Threshold IMT device (Philips Respironics Inc), and to determine whether home-based training differed from rehabilitation center training. METHODS: This four-arm, multicenter, parallel, non-inferiority trial randomized 80 active community-dwelling older men (mean age = 72.93 ± 5.02 years) to center-based groups (new IMT/PEP device or Threshold IMT device; 16 supervised sessions) or home-based groups (new IMT/PEP device or Threshold IMT device; 2 supervised sessions and individual sessions). Participants in all groups performed RMT twice a day for 8 weeks. Assessments were performed at baseline and post-training. The primary outcomes were maximum inspiratory pressure and maximal expiratory pressure. The secondary outcomes included forced vital capacity and forced expiratory volume in the first second, peak cough flow, diaphragm thickness, VO2 peak, the International Physical Activity Questionnaire score, electromyographic activities of the sternocleidomastoid muscle, and skeletal muscle mass and phase angle as measured by bioimpedance analysis. In addition, rates of adherence to each protocol were also compared. RESULTS: Among all groups, the maximal inspiratory pressure was improved post-training, while the maximal expiratory pressure showed improvement only in the IMT/PEP groups. The overall non-inferiority of the IMT/PEP device was thus validated. A statistically significant improvement in diaphragm thickness was found. However, no consistent improvement was shown in other secondary outcomes. No significant difference in training adherence rate between protocols was observed (mean adherence rate of 91-99%). CONCLUSION: Compared to the Threshold IMT, the new IMT/PEP device did not result in a significant difference in maximal inspiratory pressure but did improve maximal expiratory pressure in older men. The IMT/PEP device's improved usability, which is associated with exercise adherence, provided distinct advantages in this cohort. If proper education is first provided, home-based RMT alone may provide sufficient effects in older individuals. TRIAL REGISTRATION: This trial was registered in the database cris.nih.go.kr (registration number KCT0003901 ) on 10/05/2019.

Exercise capacity, lung and respiratory muscle function in substance use disorders.

BACKGROUND: Substance use disorder (SUD) causes conditions such as cognitive and behavioral disorders, anxiety, depression, and social isolation it also causes acute airway inflammation by affecting airway bronchial dynamics. The current study aimed to investigate the lung function, respiratory muscle strength, and exercise capacity in patients with SUD. METHODS: One hundred-eighty three patients with SUD, a total of 119 healthy controls, 54 of whom were cigarette smokers and 65 of whom were non-smokers were included in the study. Spirometric tests, respiratory muscle strength (MIP and MEP), and the 6-Minute Walk Test (6-MWT) were assessed. The III National Health and Nutrition Examination Survey were used to evaluate respiratory symptoms in patients with SUD and cigarette smokers. RESULTS: 86.3% of the SUD patients included in the study were using heroin, 9.2% were cannabis, and 5.5% were spice. The most common symptom in both SUD patients and cigarette smokers was shortness of breath, wheezing, and sputum production. After post-hoc tests, the FVC (p = 0.002), FVC (%predicted) (p < 0.0001), FEV1 (p = 0.002), FEV1 (%predicted) (p < 0.0001), FEV1/FVC (%) (p < 0.0001), PEF (p < 0.0001) and FEF%25-75 (p < 0.0001) lung function parameters were significantly lower in SUD patients than non-smokers. In addition, it was found that MIP (p < 0.0001), MIP (%predicted) (p < 0.0001), MEP (p < 0.0001), and MEP (%predicted) (p < 0.0001) values of SUD patients were significantly lower than non-smokers. CONCLUSION: The study findings indicate that substance use has an effect on lung functions and the most commonly reported symptoms are shortness of breath, wheezing, and sputum production. In addition, respiratory muscle strength and exercise capacity were decreased in SUD patients compared to non-smokers.

Relationship between symptomatic pelvic organ prolapse and respiratory muscle strength in middle-aged and older women in Northeast Brazil: a cross-sectional study.

Some respiratory muscles work in synergy with the pelvic floor (PF). Pelvic organ prolapse (POP) is characterized by weak PF muscles and has been associated with worse pulmonary ventilation function in women. To date no studies have investigated the association between respiratory muscle strength and POP. This study aimed to determine whether symptomatic POP is associated with respiratory muscle strength in middle-aged and older women. In this observational cross-sectional study, 204 community-dwelling women (41-80 years old) from Santa Cruz (Northeastern Brazil) provided information on socioeconomic characteristics, health behavior, reproductive history and symptomatic POP via a structured questionnaire. A digital manometer was used to measure their maximal inspiratory and expiratory pressures (MIP and MEP). Multiple linear regression analyses, adjusted for covariates (age, income, education, body mass index, and smoking), evaluated the association between POP and MIP/MEP. The results show that 14.7% of the sample reported symptomatic POP. These women exhibited lower mean MIP and MEP than those reporting no POP, but the intergroup difference was only significant for MEP (p = .01). The association between POP and MEP remained statistically significant, even after covariates (ß = 11.9, p = .04) were adjusted. Symptomatic POP is associated with expiratory muscle strength in middle-aged and older women. This innovative research provides important information regarding the need to evaluate the integrity of PF muscles when assessing respiratory muscle strength, which may help clinicians devise preventive and treatment strategies to improve women's health during the aging process.

The effects of forward head posture on expiratory muscle strength in chronic neck pain patients: A cross-sectional study.

OBJECTIVES: This study aims to investigate the relationship between forward head posture (FHP) and respiratory dysfunctions in patients with chronic neck pain. PATIENTS AND METHODS: Between June 2014 and November 2016 , a total of 99 patients (11 males, 88 females; mean age 54.1±9 years; range, 38 to 75 years) with chronic neck pain were evaluated for head posture by cervical lateral radiograph measuring the anterior head translation distance (FHPmm) and C7 vertebrae position (C7°). We examined the chest expansion by subtracting chest circumference from the level of xiphoid during maximal inspiration and expiration. Pain severity and neck disability were assessed using the Visual Analog Scale (VAS) and modified Neck Disability Index (MNDI), respectively. The respiratory functions were evaluated using spirometry tests, lung volumes, and maximal inspiratory and expiratory pressures (Pimax and Pemax, respectively). RESULTS: There was a negative correlation between the FHPmm with Pemax% (rho: -0.314; p=0.005). A negative correlation was also observed between C7° and Pemax, Pemax%, forced expiratory volume in one sec (FEV1)/forced vital capacity (FVC)%, forced expiratory flow (FEF)25-75%, and FEF75% (rho:-0.245, -0.349, -0.218, -0.214, and -0.259 respectively; p=0.028, 0.002, 0.035, 0.040, and 0.012, respectively). There was a positive correlation between neck disability and VAS scores (rho: 0.424; p<0.001), while there was a negative correlation between neck disability and chest expansion, maximum voluntary ventilation (rho: -0.201 and -0.217, respectively; p=0.049 and 0.046, respectively). CONCLUSION: Based on our study results, FHP is associated with expiratory muscle weakness in chronic neck pain patients. To evaluate respiratory dysfunction, chest expansion tests may be useful, although these tests are not specific to muscle weakness. Interventions about FHP and neck pain should focus on the effects of respiratory muscle training.

Evaluation of Respiratory Muscular Strength Compared to Predicted Values in Patients with Stroke.

The purpose of this study was to evaluate the inspiratory and expiratory muscle strength of individuals affected by stroke and to compare it with the predicted values in the literature considering their corresponding age. Respiratory muscle strength was evaluated in 22 elderly people who had sequels of stroke, four with right hemiparesis, 16 with left hemiparesis and two with bilateral, of ages ranging from 34 to 82 years. The collected data were submitted to statistical analysis using a Mann-Whitney test to evaluate if there was a significant difference in the average data collected when compared with a mean of the predicted data in the literature. Fourteen men and eight women were evaluated, who obtained mean values of 71.85 cmH2O and 57.75 cmH2O, respectively, for a maximal inspiratory pressure (MIP), and when compared to the predicted values for men and women, 105.41 cmH2O (p-value 0.0019) and 80.57 cmH2O (p-value 0.00464) were significantly lower. For a maximal expiratory pressure (MEP), the mean value obtained for men was 62.28 cmH2O and 49.5 cmH2O for women, whereas the predicted values in the literature were 114.79 cmH2O (p-value < 0.0001) and 78, 46 cmH2O (p-value 0.0059), respectively. In the statistical analysis, it was possible to notice that the studied population did not reach the predicted age indexes and that there was a significant difference between the median columns. In conclusion, there is a weakness in the respiratory muscles of hemiparetic men and women due to stroke.

Comparación de dos piezas bucales en la medición de PImáx y PEmáx en sujetos adultos / Comparison of two mouthpieces in the measurement of MIP and MEP in adults

Objetivos: Comparar y establecer el grado de acuerdo entre los valores de Presión Inspiratoria máxima (PImáx) y Presión Espiratoria máxima (PEmáx) medidos con pipeta bucal y boquilla de buceo, en adultos. El objetivo secundario fue evaluar el grado de acuerdo entre los valores calculados con las ecuaciones de Evans y Whitelaw y los valores máximos obtenidos con cada interfaz. Materiales y método: Se llevó a cabo un estudio observacional, descriptivo, prospectivo y transversal. Se realizó un muestreo consecutivo no probabilístico de sujetos argentinos entre 18 y 69 años de edad. Se midieron PImáx y PEmáx utilizando un sistema de válvulas unidireccionales y un manovacuómetro aneroide, con boquilla de buceo y pipeta bucal. Resultados: Se incluyeron 240 sujetos que completaron la totalidad de las mediciones con ambas interfaces. Los valores de PEmáx con pipeta bucal fueron mayores que los obtenidos con boquilla de buceo (p < 0.01), con un Coeficiente de Correlación Intraclase (ICC sigla en inglés) entre ambas de 0.80 (IC 95% 0.74-0.84). Para PImáx no hubo diferencias entre ambas interfaces, con un ICC de 0.88 (IC 95% 0.85-0.91). Los ICC para las ecuaciones de Evans y Whitelaw y los máximos valores alcanzados por los sujetos fueron de -0.15 a 0.09 mostraron un grado de acuerdo pobre. Conclusión: Los valores de PEmáx con pipeta bucal fueron mayores que los obtenidos con la boquilla de buceo. No se detectaron diferencias entre ambas interfaces para PImáx. En la población estudiada las fórmulas de Evans y Whitelaw no fueron exitosas en la predicción de presiones máximas.

Objectives: To compare and establish the degree of agreement between the values of Maximal Inspiratory Pressure (MIP) and Maximal Expiratory Pressure (MEP) measured with a plastic mouthpiece and a scuba type mouthpiece in adults. The secondary objective was to evaluate the degree of agreement between the values calculated with Evans and Whitelaw equation and the maximal values attained with each mouthpiece. Methods: We conducted an analytical observational transversal study. Sampling was non-probabilistic, of Argentinian subjects aged between 18 and 69 years old. We measured MIP and MEP with an unidirectional valves system and an aneroid manovacuometer, with a plastic mouthpiece and a scuba type mouthpiece. Results: 240 subjects were included and completed all the measurements with both mouthpieces. MEP values were higher when measured with a plastic mouthpiece than with the scuba type (p < 0.01), with an Intraclass Correlation Coefficient (ICC) between both of 0.80 (CI 95% 0.74-0.84). There were no differences in MIP between both mouthpieces, with an ICC of 0.88 (CI 95% 0.85-0.91). The ICC between Evans and Whitelaw predictive values and the maximal values attained by the subjects varied from -0.15 to 0.09, showing a poor degree of agreement. Conclusion: MEP values attained with a plastic mouthpiece are greater than those attained with a scuba type mouthpiece. There are no differences between both mouthpieces for MIP. Evans and Whitelaw equations are not successful in predicting maximal pressures in the population here studied.

Acute effects of different inspiratory resistive loading on heart rate variability in healthy elderly patients

BACKGROUND: The cardiovascular system is noticeably affected by respiration. However, whether different inspiratory resistive loading intensities can influence autonomic heart rate (HR) modulation remains unclear. OBJECTIVE: The objective was to investigate HR modulation at three different inspiratory resistive loading intensities in healthy elderly men. METHOD: This was a prospective, randomized, double-blind study that evaluated 25 healthy elderly men. Cardiac autonomic modulation was assessed using heart rate variability (HRV) indices. All of the volunteers underwent maximal inspiratory pressure (MIP) measurements according to standardized pulmonary function measurements. Three randomly-applied inspiratory resistive loading (30, 60 and 80% of MIP) intensities were then applied using an inspiratory resistance device (POWERbreathe, Southam, UK), during which the volunteers were asked to inhale for 2 seconds and exhale for 3 seconds and complete 12 breaths per minute. Each effort level was performed for 4 minutes, and HR and the distance between 2 subsequent R waves of electrocardiogram (R-R intervals) were collected at rest and at each intensity for further HRV analysis. RESULTS : The parasympathetic HRV (rMSSD, SD1 and HF) indices demonstrated lower values at 80% (rMSSD: 19±2 ms, SD1: 13±2 ms and HF: 228±61 ms2) than at 30% MIP (rMSSD: 25±3 ms, SD1: 18±2 ms and HF: 447±95 ms2; p<0.05). CONCLUSIONS: Lower inspiratory resistive loading intensities promoted a marked and positive improvement of parasympathetic sinus node modulation. .

The Relationships of Coughing to the Respiratory Muscle Strength and Pulmonary Compliance in Tetraplegic Patients

OBJECTIVE: To analyze the factors influencing the capacity of cough, the relationships between maximal respiratory pressure, lung compliance, capacity of cough, and assisted cough techniques were evaluated in tetraplegics. METHOD: The vital capacity (VC) in seated and supine position, maximum insufflation capacity (MIC), maximum inspiratory (MIP) and expiratory (MEP) pressure in seated position were measured. Unassisted and assisted peak cough flow (PCF) at two different conditions (a volume assisted method by the mechanical insufflation [PCFmic] and the manual assistance by abdominal compression [MPCF]) were evaluated in 44 tetraplegic patients. RESULTS: The mean value of VC in supine was greater than that of seated position (p<0.01). The MICs of the subjects were significantly higher than VCs in a same position (<0.01). Both volume and manual assisted method showed significantly higher PCF than unassisted PCF (p<0.01). MIP (r=0.53) correlated with UPCF as well as MEP (r=0.68), although MEP was better correlated with UPCF. CONCLUSION: Generally the therapists apply manual pressure only to increase capacity of cough, which assist the expulsive phase. The results of this study showed that both inspiratory and expulsive phases should be assisted to enhance the effectiveness of cough.