Maximal Respiratory Pressures and Maximum Voluntary Ventilation in Young Arabs: Association with Anthropometrics and Physical Activity.

BACKGROUND: Maximum inspiratory pressure (MIP), maximum expiratory pressure (MEP) and maximum voluntary ventilation (MVV) measurements assist in determining the respiratory muscle strength and endurance. These determinants of respiratory muscles vary significantly by age, gender, height, and ethnic origin. Normative values for maximum respiratory pressures (MRPs) and MVV would aid in evaluating respiratory muscle function in athletes, estimating performance, and assisting in rehabilitation. In addition, the reference values may aid in determining the efficacy of therapeutic interventions in young people with chronic respiratory diseases. The purpose of this study was to see how respiratory muscle strength indices correlated with anthropometric and physical activity characteristics in young Arabs. METHODOLOGY: The study included 80 male volunteers and 85 female volunteers ranging in age from 18 to 30 years. MicroRPM was used to measure MIP and MEP, and pulmonary function test data, including MVV values, were recorded. All subjects completed the Global Physical Activity Questionnaire (GPAQ) and anthropometric measurements. Unpaired t-tests or Mann-Whitney U-tests were used to determine male-female differences. Using the Pearson correlation coefficient and Spearman Rho correlation coefficient tests, MIP and MEP values were correlated with body composition and physical activity. Using stepwise multiple linear regression analysis, the relationships between respiratory function (MVV, MIP, and MEP) and PFT values (FVC, FEV1, and FEV1/FVC), physical activity, and sedentary behavior were investigated. RESULTS: MIP, MEP, and MVV values were significantly lower in females than in males. MIP, MEP, and MVV values had a moderate correlation with forced vital capacity, forced expiratory volume in 1 second, and height, but not with weight, BMI, or GPAQ. Age, gender, and body mass index were found to be significant predictors of maximal respiratory pressures in a young Arab population. CONCLUSION: Maximum respiratory pressures and maximal voluntary ventilation were significantly lower in young Arabs than in other ethnic groups; these values were influenced by gender and height but not by levels of physical activity.

Evaluation of the ventilatory effects on human subjects in prolonged hip-flexed/head-down restraint position.

BACKGROUND: The restraint chair is a tool used by law enforcement and correction personnel to control aggressive, agitated individuals. When initiating its use, subjects are often placed in a hip-flexed/head-down (HFHD) position to remove handcuffs. Usually, this period of time is less than two minutes but can become more prolonged in particularly agitated patients. Some have proposed this positioning limits ventilation and can result in asphyxia. The aim of this study is to evaluate if a prolonged HFHD restraint position causes significant ventilatory compromise. METHODS: Subjects exercised on a stationary bicycle until they reached 85% of their predicted maximal heart rate. They were then handcuffed with their hands behind their back and placed into a HFHD seated position for five minutes. The primary outcome measurement was maximal voluntary ventilation (MVV). This was measured at baseline, after initial placement into the HFHD position, and after five minutes of being in the position while still maintaining the HFHD position. Baseline measurements were compared with final measurements for statistically significant differences. RESULTS: We analyzed data for 15 subjects. Subjects had a mean MVV of 165.3 L/min at baseline, 157.8 L/min after initially being placed into the HFHD position, and a mean of 138.7 L/min after 5 min in the position. The mean baseline % predicted MVV was 115%; after 5 min in the HFHD position the mean was 96%. This 19% absolute difference was statistically significant (p = 0.001). CONCLUSIONS: In healthy seated male subjects with recent exertion, up to five minutes in a HFHD position results in a small decrease in MVV compared with baseline MVV levels. Even with this decrease, mean MVV levels were still 96% of predicted after five minutes. Though a measurable decrease was found, there was no clinically significant change that would support that this positioning would lead to asphyxia over a five-minute time period.

Respiratory Muscle Strength and Ventilatory Function Outcome: Differences Between Trained Athletes and Healthy Untrained Persons.

It is known that the maximum mouth inspiratory pressure (MIP) and expiratory pressure (MEP) vary with age, weight, height, and skeletal muscle mass. However, the influence of physical training on ventilatory function outcomes is an area of limited understanding. The aim of this study was to investigate the respiratory muscle strength and its relation to spirometry variables in untrained healthy persons versus trained athletes. MIP and MEP were assessed in 22 power athletes and 28 endurance athletes, and in 24 age- and sex-matched normal healthy subjects (control group). The measurement was done with a mouth pressure meter. We found that respiratory muscle strength and ventilatory function in endurance athletes were outstandingly superior to that in power athletes; the latter's muscle strength was better than that of healthy untrained controls. Both MIP and MEP significantly correlated with the maximum voluntary ventilation (MVV) in both power athletes and controls, but not so in endurance athletes. The corollary is that the intensive endurance training could result in the improvement of respiratory muscle strength, meeting the maximum upper limit of functional reserve of respiratory muscles and the corresponding ventilation. On the other hand, targeted training of respiratory muscle strength may be an effective strategy to increase ventilatory function in power athletes, particularly those having a low maximum inspiratory and expiratory pressure, and in less physically fit healthy persons.

Maximum Voluntary Ventilation and Its Relationship With Clinical Outcomes in Subjects With COPD.

BACKGROUND: Previous studies have reported that maximum voluntary ventilation (MVV) may be better associated with commonly used outcomes in COPD than FEV1 and may provide information on respiratory mechanics. In this study, we aimed to investigate the relationship between MVV and clinical outcomes in COPD and to verify whether MVV predicts these outcomes better than FEV1. METHODS: We conducted a cross-sectional study involving individuals with COPD. Lung function was assessed with spirometry; maximum inspiratory and expiratory pressures (PImax and PEmax, respectively) were assessed with manuvacuometry; and functional exercise capacity was assessed with the 6-min-walk test (6MWT). Dyspnea was assessed with the modified Medical Research Council (mMRC) scale; functional status was assessed with the modified Pulmonary Functional Status and Dyspnea Questionnaire (PFSDQ-m); and health status was assessed with the COPD Assessment Test (CAT). Correlations were verified with the Spearman coefficient, and stepwise multiple linear regression models investigated the predictors of clinical outcomes. RESULTS: Our study included 157 subjects: 82 males; median (interquartile range) age 66 (61-73) y; FEV1 46 (33-57) % predicted; 6MWT 86 (76-96) % predicted; PFSDQ-m total score 34 (14-57); and CAT total score 13 (7-19). Moderate correlations were found between MVV and PImax (r = 0.40), 6MWT (r = 0.50), mMRC (r = -0.56), and total scores on the PFSDQ-m (r = -0.40) and the CAT (r = -0.54). In the regression models, MVV was a predictor of almost all clinical outcomes, unlike FEV1. CONCLUSIONS: MVV correlates moderately with clinical outcomes commonly used in the evaluation of individuals with COPD, and MVV is a better predictor of respiratory muscle strength, functional exercise capacity, and patient-reported outcomes than FEV1.

The effect of core stability training with ball and balloon exercise on respiratory variables in chronic non-specific low back pain: An experimental study.

BACKGROUND: Studies have shown the involvement of respiratory characteristics and their relationship with impairments in non-specific low back pain (NS-LBP). The effects of core stability with a combined ball and balloon exercise (CBB) on respiratory variables had not been investigated. OBJECTIVE: To evaluate the effectiveness of CBB on respiratory variables among NS-LBP patients. STUDY DESIGN: pre- and post-experimental study. PARTICIPANTS: Forty participants were assigned to an experimental group (EG) [n = 20] and control group (CG) [n = 20] based on the study criteria. INTERVENTIONS: The EG received CBB together with routine physiotherapy and the CG received routine physiotherapy over a period of 8 weeks. Participants were instructed to carry out the exercises for 3 days per week. The training was evaluated once a week and the exercises progressed based on the level of pain. OUTCOME MEASURES: Primary outcomes were maximum inspiratory pressure (MIP), maximum expiratory pressure (MEP) and maximum voluntary ventilation (MVV). The secondary outcomes were measured in the numeric rating scale (NRS), total faulty breathing scale (TFBS), cloth tape measure (CTM) and lumbo-pelvic stability. RESULTS: The MIP increased significantly among the EG when compared with that in the CG (p > 0.05).The EG showed a significant increase in MVV (p = 0.04) when compared to the CG (p = 0.0001). There was a significant reduction in pain for both groups. The MEP, TFBS, chest expansion and core stability showed no changes in either group. CONCLUSION: CBB was effective in improving respiratory variables among NS-LBP patients.

Synchronous multiple primary lung cancers with shared EGFR mutation but differential imaging findings and pathological subtypes: A case report.

Lung cancer is a leading cause of cancer mortality worldwide. As the incidence of lung cancer increases in recent years, the number of patients diagnosed with synchronous multiple primary lung cancers (SMPLC) is also rising. SMPLC diagnosis is often made based on the clinical course, imaging findings, and histologic and molecular features. Standard lobectomy is the main therapeutic modality for SMPLC. Because maximum retention of lung function is essential, sublobectomy is also a commonly used surgical strategy when appropriate. The question is how to optimize the sequence of lobectomy and sublobectomy for patients with SMPLC. Thoracoscope lobectomy for the primary lesion plus sublobectomy for the secondary lesions is the most commonly used approach. Here we present a case of SMPLC with sublobectomy followed by lobectomy.

Correlação da ventilação voluntária máxima com a força e resistência dos músculos respiratórios em jovens / Correlation of maximum voluntary ventilation to the strength and resistance of young respiratory muscles

A ventilação voluntária máxima é um dos testes difundidos para avaliação da resistência da musculatura respiratória, mesmo sem ser validado para este fim. Na literatura ainda são encontradas controvérsias quanto a interpretação e aplicabilidade do uso da VVM na prática clínica. OBJETIVO: Verificar a correlação entre a ventilação voluntária máxima e a força e resistência dos músculos respiratórios em jovens hígidos. MATERIAIS E MÉTODOS: Estudo observacional de corte transversal realizado na Clínica. Foram incluídos indivíduos > 18 anos, de ambos os sexos e hígidos. Os participantes tiveram sua avaliação da força muscular respiratória através do manovacuômetro, no qual se obteve a Pimáx e Pemáx. A resistência foi avaliada através do teste de carga constante pelo Power Breathe, utilizando 60% da Pimáx. A ventilação voluntária máxima foi realizada pelo espirômetro. Para a correlação das variáveis Pimáx, Pemáx e VVM foi aplicado o teste de correlação de Pearson. O estudo foi aprovado pelo comitê de ética, CAAE 10849519.9.0000.5544. RESULTADOS: Foram avaliados 27 participantes, em que 59,3% eram do sexo masculino e 55,6% ativos. A ventilação voluntária máxima com a Pimáx e Pemáx, apresentaram respectivamente p = 0,04 e 0,02 e r = 0,53 e 0,57. CONCLUSÃO: O teste de ventilação voluntária máxima possui uma correlação moderada com a força muscular respiratória, e não obtém correlação com o teste de carga constante.

Maximum voluntary ventilation is one of the widespread tests for assessing respiratory muscle strength, even without being validated for this purpose. Controversies are still found in the literature regarding the interpretation and applicability of the use of MVV in clinical practice. OBJECTIVE: To verify the correlation between maximum voluntary ventilation and respiratory muscle strength and endurance in healthy youngsters. MATERIALS AND METHODS: Observational cross-sectional study conducted at the Clinic. Individuals> 18 years of age, of both sexes and healthy were included. Participants had their respiratory muscle strength assessment using a manovacuometer, in which Pimax and Pmax were obtained. The resistance was evaluated through the constant load test by Power Breathe, using 60% of the Pimáx. Maximum voluntary ventilation was performed by a spirometer. Pearson's correlation test was applied to correlate the variables Pimax, Pmax and VVM. The study was approved by the ethics committee, CAAE 10849519.9.0000.5544. RESULTS: 27 participants were evaluated, of which 59.3% were male and 55.6% were active. The maximum voluntary ventilation with Pimax and Pmax, presented respectively p = 0.04 and 0.02 and r = 0.53 and 0.57. CONCLUSION: The maximum voluntary ventilation test has a moderate correlation with respiratory muscle strength and has no correlation with the constant load test.

Estimated individual inhaled dose of fine particles and indicators of lung function: A pilot study among Chinese young adults.

Fine particle (PM2.5)-related lung damage has been reported in most studies regarding environmental or personal PM2.5 concentrations. To assess effects of personal PM2.5 exposures on lung function, we recruited 20 postgraduate students and estimated the individual doses of inhaled PM2.5 based on their microenvironmetal PM2.5 concentrations, time-activity patterns and refereed inhalation rates. During the period of seven consecutive days in each of the four seasons, we repeatedly measured the daily lung function parameters and airway inflammation makers such as fractional exhaled nitric oxide (FeNO) as well as systemic inflammation markers including interleukin-1ß on the final day. The high individual dose (median (IQR)) of inhaled PM2.5 was 957 (948) µg/day. We observed a maximum FeNO increase (9.1% (95%CI: 2.2-15.5)) at lag 0 day, a maximum decrease of maximum voluntary ventilation (11.8% (95% CI: 4.6-19.0)) at lag 5 day and a maximum interleukin-1ß increase (103% (95% CI: 47-159)) at lag 2 day for an interquartile range increase in the individual dose of inhaled PM2.5 during the four seasons. Short-term exposure to PM2.5 assessed by the individual dose of inhaled PM2.5 was associated with higher airway and systemic inflammation and reduced lung function. Further studies are needed to understand better underlying mechanisms of lung damage following acute exposure to PM2.5.

Maximum Voluntary Ventilation in a Population Residing at 2,240 Meters Above Sea Level.

BACKGROUND: Measured maximum voluntary ventilation (MVV) correlates with maximum ventilatory capacity during exercise. As a shortcut, MVV is often estimated by multiplying measured FEV1 times 35 or 40, but this index varies with altitude due to reduced air density. The objective was to describe MVV in healthy individuals residing at 2,240 m above sea level and compare it with the reference values customarily employed. METHODS: We recruited a convenience sample of respiratory-healthy, non-obese volunteers >10 y of age who had resided for >2 y in Mexico City. All participants performed forced spirometry and MVV according to current standards. Multiple regression models were fitted, including age, height, and measured FEV1, separately for males and females to obtain reference values. The impact of lower air density on MVV at this elevation was estimated from the reported increase in peak flow in relation to altitude. RESULTS: We studied 381 individuals (210 females [55.1%]) age 10-80 y with a mean MVV of 145.6 ± 48 L/min. Both FEV1 × 35 and FEV1 × 40 underestimated the MVV observed: in males by approximately 26% and in females by approximately 10%. MVV for our population approached FEV1 × 45 (98 ± 15.6% of real MVV). Multiple regression models including height, weight, and measured FEV1 explained 70% of residual variability once sex was taken into account. CONCLUSIONS: At an altitude of 2,240 m, MVV is about 45 times the measured FEV1, and it can be estimated for other altitudes. The best predicting equations for MVV were calculated separately for females and males and included the following predictors: age, age2, and measured FEV1. The study found that reference values for MVV from studies conducted at sea level are inaccurate at this altitude.

Compact Eucapnic Voluntary Hyperpnoea Apparatus for Exercise-Induced Respiratory Disease Detection.

Eucapnic voluntary hyperpnoea (EVH) challenge provides objective criteria for exercise-induced asthma (EIA) or exercise-induced bronchoconstriction (EIB), and it was recommended to justify the use of inhaled ß2-agonists by athletes for the Olympics. This paper presents the development of a compact and easy-to-use EVH apparatus for assessing EIB in human subjects. The compact apparatus has been validated on human subjects and the results have been compared to the conventional EVH system. Twenty-two swimmers, including eleven healthy subjects and eleven subjects who had been physician-diagnosed with asthma, were recruited from sport and recreation centers throughout Auckland, New Zealand. Each subject performed two EVH challenge tests using the proposed breathing apparatus and the conventional Phillips EVH apparatus on separate days, respectively. Forced expiratory volume in one second (FEV1) was measured before and after the challenges. A reduction in FEV1 of 10% or more was considered positive. Of the eleven subjects who were previously diagnosed with asthma, EIB was present in all subjects (100%) in the compact EVH group, while it was presented in ten subjects (90.91%) in the conventional EVH challenge group. Of the eleven healthy subjects, EIB was present in one subject (4.55%) in the compact EVH group, while it was not present in the conventional EVH group. Experimental results showed that the compact EVH system has potential to become an alternative tool for EIB detection.

Feasibility to apply eucapnic voluntary hyperventilation in young elite athletes.

INTRODUCTION: Exercise-induced bronchoconstriction (EIB) is more common in athletes compared to the general population. The eucapnic voluntary hyperventilation test is used to detect EIB in adult athletes. It is however unclear whether this technique is also applicable to young athletes. METHODS: Young athletes (basketball (n = 13), football (n = 19), swimming (n = 12)) were recruited at the start of their elite sports career (12-14 years). Eight age-matched controls were also recruited. Eucapnic voluntary hyperventilation test was performed according to ATS guidelines in all subjects. A second (after 1 year, n = 32) and third (after 2 years, n = 39) measurement was performed in a subgroup of athletes and controls. RESULTS: At time of first evaluation, 3/13 basketball players, 4/19 football players, 5/11 swimmers and 1/8 controls met criteria for EIB (fall in FEV1≥10% after EVH). A ventilation rate of >85% of the maximal voluntary ventilation (MVV) is recommended by current guidelines (for adults) but was only achieved by a low number of individuals (first occasion: 27%, third occasion: 45%) However, MVV in young athletes corresponds to 30 times FEV1, which is equivalent to 85% of MVV in adults. A threshold of 70% of MVV (21 times FEV1) is feasible in the majority of young athletes. CONCLUSION: EIB is present in a substantial number of individuals at the age of 12-14 years, especially in swimmers. This underscores the importance of screening for EIB at this age. EVH is feasible in young elite athletes, however target ventilation needs to be adjusted accordingly.

Pulmonary function of patients with chronic neck pain: a spirometry study.

BACKGROUND: Chronic neck pain is one of the most common musculoskeletal pain conditions experienced by many people during their lives. Although patients with neck pain are managed predominantly as musculoskeletal patients, there are indications that they also have poor pulmonary function. The aim of this study was to examine whether patients with chronic neck pain have spirometric abnormalities and whether neck pain problems and psychological states are associated with these abnormalities. METHODS: Forty-five participants with chronic neck pain and 45 well-matched healthy controls were recruited. Spirometry was used to assess participants' pulmonary function. Neck muscle strength, endurance of deep neck flexors, cervical range of motion, forward head posture, psychological states, disability, and pain intensity were also evaluated. RESULTS: The results showed that patients with chronic neck pain yielded significantly reduced vital capacity, FVC, expiratory reserve volume, and maximum voluntary ventilation (P < .05), but peak expiratory flow, FEV1, and FEV1/FVC ratio were not affected (P > .05). Strength of neck muscles, pain intensity, and kinesiophobia were found to be significantly correlated (r > 0.3, P < .05) with respiratory function. CONCLUSIONS: Patients with chronic neck pain do not have optimal pulmonary function. Cervical spine muscle dysfunction in parallel with pain intensity and kinesiophobia are factors that are associated mainly with this respiratory dysfunction.

Cardiorespiratory response to aerobic exercise programs with different intensity: 20 weeks longitudinal study.

CONTEXT: participation in regular intensive exercise is associated with a modest increase in left ventricular wall thickness and cavity size. The magnitude of improvement depends on frequency, intensity, type, and duration of exercise program. AIMS: to determine the effect of sports training on LV morphology and function, lung function, and to know the intensity of the exercise program enough for these changes. SETTINGS AND DESIGN: this was a longitudinal study (20 weeks duration) done on the medical college students. MATERIAL AND METHODS: three groups, doing exercise at different intensities, high intensity group (HG) [74.9±3.9 %HRmax], low intensity group (LG) [59.46±4.1%HRmax] and no exercise group (NG) were made, and their assessments were done using the echocardiography and pulmonary function test three times, first before start of the exercise program, second at the end of 10th week, and then at the end of the 20th week. STATISTICAL ANALYSIS USED: 3 × 3 Anova test and Bonferroni's post-test using Graph pad prism5 software. RESULTS: significant improvement was seen in HG in majority of cardio respiratory parameters (VO2max, heart rate, LVIDD, LVIDS, EDV, MVV, PEFR, FVC) as compared to the LG (VO2max, heart rate, MVV, PEFR) and this improvement was specially seen at the end of the twentieth week. CONCLUSIONS: twenty weeks of training is helpful in improving aerobic power, MVV, and PEFR even the exercise is of moderate (LG) to high intensity (HG) but for overall cardio respiratory development physical training must be associated with very hard intensity if duration of the exercise program is short.

Análise comparativa entre a medida direta e indiretada ventilação voluntária máxima em pacientescom doença pulmonar obstrutiva crônica / Comparative analysis between direct and indirect maximum voluntary ventilation in patients with chronic obstructive pulmonary disease

Objetivo. Verificar a confiabilidade de obter a ventilação voluntária máxima por meio de estimativas com base no volume expiratório forçado no primeiro segundo (VEF1) em pacientes com doença pulmonar obstrutiva crônica. Método. Participaram do estudo 32 pacientes com doença pulmonar obstrutiva crônica, sendo 21 homens, com média de idade de 66 ± 8,3 anos. Todos foram submetidos a espirometria e a prova de ventilação voluntária máxima. Foram utilizados os testes de Friedman e de Wilcoxon para comparar a ventilação em estudo, obtida de modo indireto com o valor encontrado por espirometria. O nível de significância preestabelecido foi 5%. Resultados. Dentre as fórmulas indiretas para estimar a ventilação voluntária máxima, apenas a VEF1 x 40 apresentou aproximação com essa ventilação, obtida diretamente (p < 0,05). Conclusão. A melhor estimativa indireta capaz de substituir a medida direta da ventilação voluntária máxima, em pacientes com doença pulmonar obstrutiva crônica, é a fórmula VEF1 x 40.

Objective. To avaluate the reliability of obtaining the maximum voluntary ventilation via estimate values of the forced expiratory volume in the first second (FEV1) in patients with chronic obstructive pulmonary disease. Method. The population was composed of 32 patients with chronic obstructive pulmonary disease, 21 of which were male, and with a mean age in the range of 66 ± 8.3 years. All the patients undergone espirometry and maximum voluntary ventilation test. Friedman’s and Wilcoxon’s tests were used to compare indirect values of maximum voluntary ventilation with those obtained via espirometry. Values were considered statistically significant if p < 0.05. Results. Amongst the indirect formulae used to estimate the maximum voluntary ventilation only FEV1 x 40 showed an approximation with the directly obtained value of MVV (p < 0.05). Conclusion. Formula FEV1 x 40 is the best indirect estimate capable of replacing the direct measure of maximum voluntary ventilation in patients with chronic obstructive pulmonary disease.