Respiratory muscular strength in children with mucopolysacaridosis: comparison with predictive equations.

BACKGROUND: Mucopolysaccharidoses (MPS) are rare metabolic diseases that impair respiratory function leading to respiratory failure. This study aimed to compare maximal inspiratory and expiratory pressures (MIP and MEP) obtained in children with MPS and compare with predicted values from previous studies involving healthy children. METHODS: This is a cross-sectional study, in which the chest deformity was evaluated; MIP, MEP through digital manometer, and lung function through spirometry. MIP and MEP were compared with five different predict equations and with a control group of healthy children. Agreement between respiratory muscle weakness regarding absolute values of MIP and MEP in relation to predictive values by the equations included in the study were assessed by Kappa coefficient. RESULTS: MPS group was composed of 22 subjects. 45.5% had pectus carinatum, 36.4% pectus excavatum, and presented lower MIP (37.14±36.23 cmH2O) and MEP (60.09±22.3 cmH2O) compared with control group (22 healthy subjects) (MIP: 91.45±35.60; MEP: 95.73±22.38). Only the MEP equations proposed by Tomalak et al. were close to those found in our MPS children (P=0.09). In the MPS group it was observed a weak agreement between inspiratory weakness through absolute and predicted values in only two equations: Tomalak et al. and Domenèch-Clar et al. (for both: k=0.35, P value =0.03); and for MEP a moderate agreement was found using all predictive equations. CONCLUSIONS: In MPS children MRP data should not be normalized using the reference equations for healthy ones, is more coherent to longitudinally follow absolute pressures and lung volumes in this group.

[Relationship between frailty and functional status in lung transplant candidates]. / Relación entre la fragilidad y la capacidad funcional en los pacientes candidatos a trasplante de pulmón.

INTRODUCTION: Lung transplant (LT) is one of the therapeutic options for patients with terminal respiratory diseases. It is highly important to incorporate the functional status and frailty assessment into the selection process of candidates for LT. OBJECTIVES: Identify the prevalence of frailty in the LT waiting list. Study the relationship between frailty, functional status, Lung Allocation Score (LAS) and muscular dysfunction. METHODOLOGY: Descriptive transversal study of patients on the waiting list for LT. POPULATION: 74 patients with chronic respiratory diseases assessed by the lung transplant committee and accepted to be transplanted in a university hospital in Barcelona. The outcome variables were frailty status was evaluate for SPPB test, functional capacity was evaluate for the six-minute walking test (6MWT) and muscular dysfunction. The results were analyzed with the statistical package STATA 12. RESULTS: Sample of 48 men and 26 women, with a median age of 56.55 years (SD 10.87. The prevalence of frailty assessed with the SPPB was 33.8% (8.1% are in frailty and 25.7% are in a state of pre-frailty). There is a relationship between the SPPB, 6MWT and maximal inspiratory pressure, but not with others force values. There is a relationship between the risk of frailty (scores below 9 in SPPB) and the meters walked in 6 but not with the LAS. CONCLUSIONS: The risk of frailty in patients with terminal chronic respiratory diseases is high. Frailty is related with functional capacity, but not with LAS.

External Jet Nebulization and Measured Ventilator Performance.

BACKGROUND: During invasive ventilation, external flow jet nebulization results in increases in displayed exhaled tidal volumes (VT). We hypothesized that the magnitude of the increase is inaccurate. An ASL 5000 simulator measured ventilatory parameters over a wide range of adult settings: actual VT, peak inspiratory pressure (PIP), and time to minimum pressure. METHODS: Ventilators with internal and external flow sensors were tested by using a variety of volume and pressure control modes (the target VT was 420 mL). Patient conditions (normal, COPD, ARDS) defined on the ASL 5000 were assessed at baseline and with 3.5 or 8 L/min of added external flow. Patient-triggering was assessed by reducing muscle effort to the level that resulted in backup ventilation and by changing ventilator sensitivity to the point of auto-triggering. RESULTS: Results are reported as percentage change from baseline after addition of 3.5 or 8 L/min external flow. For ventilators with internal flow sensors, changes in displayed exhaled VT ranged from 10% to 118%, however, when using volume control, actual increases in actual VT and PIP were only 4%-21% (P = .063, .031) and 6%-24% (P = .25, .031), respectively. Changes in actual VT correlated closely with changes in PIP (P < .001; R2 = 0.68). For pressure control, actual VT decreased by 3%-5% (P = .031) and 4%-9% (P = .031) with 3.5 and 8 L/min respectively, PIP was unchanged. With external flow sensors at the distal Y-piece junction, volume and pressure changes were statistically insignificant. The time to minimum pressure increased at most by 8% (P = .02) across all modes and ventilators. The effects on muscle pressure were minimal (∼1 cm H2O), and ventilator sensitivity effects were nearly undetectable. CONCLUSIONS: External flow jet nebulization resulted in much smaller changes in volume than indicated by the ventilator display. Statistically significant effects were confined primarily to machines with internal flow sensors. Differences approached the manufacturer-reported variation in ventilator baseline performance. During nebulizer therapy, effects on VT can be estimated at the bedside by monitoring PIP.

Reducing Airway Occlusion Time Without Losing Accuracy to Predict Successful Mechanical Ventilator Liberation During the Measurement of the Timed Inspiratory Effort Index.

BACKGROUND: In 2013, a new predictor of successful mechanical ventilation liberation named timed inspiratory effort (TIE) index was devised with the normalization of the maximum inspiratory pressure (obtained within 60 s of unidirectional airway occlusion) with the time at which the value was reached. The aim of this study was to verify whether the presence of a sequence of a certain number of inspiratory effort values between 30-60 s > 1.0 cm H2O/s could predict weaning success in a performance comparable to the TIE index. METHODS: This was a retrospective observational study using 4 databases of previous studies on the TIE index. All patients receiving mechanical ventilation for ≤ 24 h were eligible. Liberation from mechanical ventilation-extubation decisions was made based on performance with spontaneous breathing trials. P < .05 was considered significant. The performance of the TIE index was evaluated by calculating the area under the receiver operating characteristics (AUROC) curve. RESULTS: From 349 eligible patients, 165 subjects were selected for analysis. The AUROC for the TIE index in the studied sample was 0.92 (95% CI 0.87-0.97, P < .001). A sequence of ≤ 4 inspiratory efforts > 1.0 cm H2O/s was found in 51.5% of the subjects, with successful ventilatory liberation occurring in 95.3%. The highest specificity values belonged to the sequence of ≤ 4 and ≤ 5 inspiratory efforts > 1.0 cm H2O/s; the highest positive predictive value and positive likelihood ratio belonged to the sequence of ≤ 4 inspiratory efforts > 1.0 cm H2O/s. The mean time that could have been spared if the procedure were interrupted after the first sequence of 4 inspiratory efforts > 1.0 cm H2O/s was 23 ± 3 s. CONCLUSIONS: The presence of a sequence of ≤ 4 inspiratory efforts > 1.0 cm H2O/s during the TIE index measurement was a reliable predictor of weaning success, which could allow timely interruption of the procedure and entail a substantial reduction in airway occlusion time.

Reliability and Validity of Maximal Respiratory Pressures.

BACKGROUND: Maximal respiratory pressure is used to assess the inspiratory and expiratory muscles strength by using maximal inspiratory pressure (PImax) and maximal expiratory pressure (PEmax). This study aimed to summarize and evaluate the reliability and validity of maximal respiratory pressure measurements. METHODS: This systematic review followed the Consensus-based Standards for the Selection of Health Measurement Instruments (COSMIN) recommendations and was reported by using the PRISMA checklist. Studies published before March 2023 were searched in PubMed and EMBASE databases. RESULTS: A total of 642 studies were identified by using the online search strategy and manual search (602 and 40, respectively). Twenty-three studies were included. The level of evidence for test-retest reliability was moderate for PImax and PEmax (intraclass correlation coefficient > 0.70 for both), inter-rater reliability was low for PImax and very low for PEmax (intraclass correlation coefficient > 0.70 for both), and the measurement error was very low for PImax and PEmax. In addition, concurrent validity presented a high level of evidence for PImax and PEmax (r > 0.80). CONCLUSIONS: Only concurrent validity of maximal respiratory pressure measured with the manometers evaluated in this review presented a high level of evidence. The quality of clinical studies by using maximal respiratory pressure would be improved if more high-quality studies on measurement properties, by following well established guidelines and the COSMIN initiative, were available.

Evaluation of patients with chronic obstructive pulmonary disease by maximal inspiratory pressure and diaphragmatic excursion with ultrasound sonography.

BACKGROUND: Decreased respiratory muscle strength and muscle mass is key in diagnosing respiratory sarcopenia. However, the role of reduced diaphragm activity, expressed as the maximal level of diaphragmatic excursion (DEmax), in diagnosing respiratory sarcopenia in patients with chronic obstructive pulmonary disease (COPD) remains unclear. This study aimed to characterize patients with COPD and low DEmax and maximal inspiratory pressure (MIP), a measure of inspiratory muscle strength, and assess the role of DEmax in respiratory sarcopenia. METHODS: Patients with COPD underwent spirometry, exercise tolerance (VO2peak) test, and MIP measurement. DEmax and sternocleidomastoid thickness at the maximal inspiratory level (TscmMIL) were assessed using ultrasound sonography. RESULTS: Overall, 58 patients with COPD (median age, 76 years; median %FEV1, 51.3 %) were included, 28 of whom showed a %MIP of ≥80 %, defined as having preserved MIP. Based on the %MIP of 80 % and median value of DEmax (48.0 mm) as thresholds, the patients were stratified into four groups: both-high (n = 18), %MIP-alone low (n = 11), DEmax-alone low (n = 10), and both-low (n = 19) groups. The both-low group exhibited the lowest %FEV1, Δinspiratory capacity, VO2peak, and TscmMIL, and these values were significantly lower than those of the both-high group. Except for %FEV1, these values were significantly lower in the both-low group than in the %MIP-alone low group despite adjusting DEmax level for body mass index. CONCLUSION: Measuring DEmax along with MIP can characterize patients with COPD, reduced exercise capacity, and decreased accessory respiratory muscle mass and can help diagnose respiratory sarcopenia.

Effects of Modified Diaphragmatic Training on Gastroesophageal Reflux Disease Questionnaire Score, Diaphragmatic Excursion, and Maximum Inspiratory Pressure in Adults with Gastroesophageal Reflux Disease After COVID-19: A Single-Blinded Randomized Control.

BACKGROUND: Although diaphragmatic training has been shown to improve gastroesophageal reflux disease (GERD) symptoms, its effectiveness in adults with GERD after COVID-19 has not been evaluated. This study examined the effectiveness of modified diaphragmatic training (MDT) on GERD questionnaire (GERDQ) score, diaphragmatic excursion, and maximum inspiratory pressure (MIP) in adults with GERD after COVID-19. METHODS: This single-blinded randomized control trial was conducted at Persahabatan Hospital from February to April 2023. The medical records of 364 patients with persistent gastrointestinal symptoms were evaluated; among these potential participants, 302 had symptoms before, and 62 after, COVID-19 infection. Fifty of these patients fulfilled the study inclusion and exclusion criteria and were randomly assigned to the intervention (n = 25) or control (n = 25) groups. Four weeks of diaphragmatic training were followed by MDT or standard diaphragmatic training. A follow-up assessment was conducted 30 days after the beginning of the training. RESULTS: The GERDQ score was significantly decreased in the pre-post-intervention group (10.44 ± 2.00 vs 1.84 ± 2.17) and the control group (8.64 ± 0.57 vs 3.32 ± 1.49), with p < 0.001. The intervention group showed significant improvements in the right diaphragmatic excursion (RDE) (44% vs 11.87%), left diaphragmatic excursion (LDE) (46.61% vs 13.62%), and MIP (75.26% vs 23.97%) compared with the control group. CONCLUSION: MDT in adults after COVID-19 with GERD enhanced diaphragmatic excursion and MIP and decreased symptoms of gastroesophageal reflux by 8.60 points of GERDQ. Respiratory symptoms and other side effects were comparable between the groups.

Maximal Respiratory Pressure Reference Equations in Healthy Adults and Cut-off Points for Defining Respiratory Muscle Weakness.

INTRODUCTION: Maximal inspiratory and expiratory pressures (PImax/PEmax) reference equations obtained in healthy people are needed to correctly interpret respiratory muscle strength. Currently, no clear cut-off points defining respiratory muscle weakness are available. We aimed to establish sex-specific reference equations for PImax/PEmax in a large sample of healthy adults and to objectively determine cut-off points for respiratory muscle weakness. METHODS: A multicentre cross-sectional study was conducted across 14 Spanish centres. Healthy non-smoking volunteers aged 18-80 years stratified by sex and age were recruited. PImax/PEmax were assessed using uniform methodology according to international standards. Multiple linear regressions were used to obtain reference equations. Cut-off points for respiratory muscle weakness were established by using T-scores. RESULTS: The final sample consisted of 610 subjects (314 females; 48 [standard deviation, SD: 17] years). Reference equations for PImax/PEmax included body mass index and a squared term of the age as independent variables for both sexes (p<0.01). Cut-off points for respiratory muscle weakness based on T-scores ≥2.5 SD below the peak mean value achieved at a young age were: 62 and 83cmH2O for PImax and 81 and 109cmH2O for PEmax in females and males, respectively. CONCLUSION: These reference values, based on the largest dataset collected in a European population to date using uniform methodology, help identify cut-off points for respiratory muscle weakness in females and males. These data will help to better identify the presence of respiratory muscle weakness and to determine indications for interventions to improve respiratory muscle function.

Impacto de un Programa de Recuperación Funcional en Músculos Ventilatorios y Apendiculares en Pacientes Post-ventilación Mecánica por COVID-19 / Impact of a Functional Recovery Program on Ventilatory and Appendicular Muscles in Patients Post-mechanical Ventilation for COVID-19

Los pacientes con COVID-19 subsidiarios de ventilación mecánica (VM), evolucionan con consecuencias funcionales en la musculatura ventilatoria y apendicular que no necesariamente se abordan de manera diferenciada. El objetivo de esta investigación fue evaluar el impacto de un programa de recuperación funcional en estos pacientes y determinar si las intervenciones afectan de manera diferenciada a las funciones ventilatorias y musculatura apendicular, utilizando pruebas de bajo costo. Se evaluaron 47 pacientes con COVID-19 que estuvieron en VM. Posterior a una espirometría basal se les realizó; presión inspiratoria máxima (PIMáx), fuerza de prensión palmar (FPP), prueba de pararse y sentarse (PPS) y Prueba de caminata en 6 minutos (PC6m), antes y después del plan de intervención. Este programa incluyó ejercicios aeróbicos y de fuerza supervisados por dos sesiones semanales de 60 minutos durante 3 meses. Después del programa, se observaron mejoras significativas en la capacidad vital forzada (CVF), el volumen espiratorio en el primer segundo (VEF1) y la PIMáx. Se encontraron relaciones significativas entre estas mediciones y la distancia recorrida de la PC6m, la FPP y la PPS. En conclusión, el programa de recuperación funcional en pacientes con COVID-19 que requirieron VM, beneficia tanto la función ventilatoria como la fuerza muscular apendicular. Las pruebas de fuerza muscular apendicular pueden ser útiles para evaluar la recuperación ya que pueden entregar información diferenciada de sus rendimientos. Por último, se necesita más investigación para comprender mejor la respuesta de estos pacientes a la rehabilitación.

SUMMARY: Patients with COVID-19 requiring mechanical ventilation (MV) evolve with functional consequences in the ventilatory and appendicular muscles that are not necessarily addressed in a differentiated manner. The objective of this research was to evaluate the impact of a functional recovery program in these patients and determine if the interventions differentially affect ventilatory functions and appendicular muscles, using low- cost tests. 47 patients with COVID-19 who were on MV were evaluated. After a baseline spirometry, they were performed; maximum inspiratory pressure (MIP), handgrip strength (HGS), sit to stand test (STST) and 6-minute walk test (6MWT), before and after the intervention plan. This program included supervised aerobic and strength exercises for two weekly 60-minute sessions for 3 months. After the program, significant improvements were observed in forced vital capacity (FVC), expiratory volume in the first second (FEV1) and MIP. Significant relationships were found between these measurements and the distance traveled of the 6MWT, the HGS and the STST. In conclusion, the functional recovery program in patients with COVID-19 who required MV benefits both ventilatory function and appendicular muscle strength. Appendicular muscle strength tests can be useful to evaluate recovery since they can provide differentiated information about your performances. Finally, more research is needed to better understand the response of these patients to rehabilitation.

Maximal expiratory pressure compared with maximal expiratory pressure during induced cough as a predictor of extubation failure.

OBJECTIVE: To compare the diagnostic performance of maximal expiratory pressure with maximal expiratory pressure during induced cough for predicting extubation failure within 72 hours in patients who completed a spontaneous breathing trial (SBT). METHODS: The study was conducted between October 2018 and September 2019. All patients aged over 18 years admitted to the intensive care unit who required invasive mechanical ventilation for over 48 hours and successfully completed a spontaneous breathing trial were included. The maximal expiratory pressure was assessed with a unidirectional valve for 40 seconds, and verbal encouragement was given. The maximal expiratory pressure during induced cough was measured with slow instillation of 2mL of a 0.9% saline solution. The primary outcome variable was extubation failure. RESULTS: Eighty patients were included, of which 43 (54%) were male. Twenty-two patients [27.5% (95%CI 18.9 - 38.1)] failed extubation within 72 hours. Differences were observed in the maximal expiratory pressure during induced cough between the group who failed extubation, with a median of 0cmH2O (P25-75: 0 - 90), and the group without extubation failure, with a median of 120cmH2O (P25-75: 73 - 120); p < 0.001. CONCLUSION: In patients who completed a spontaneous breathing trial, the maximal expiratory pressure during induced cough had a higher diagnostic performance for predicting extubation failure within 72 hours.Clinicaltrials.gov Registry: NCT04356625.

Cambios en el índice de stress y presión inspiratoria pico posterior a neumoperitoneo en colecistectomía laparoscópica / Changes in Stress Index and Peak Inspiratory Pressure after Pneumoperitoneum in Laparoscopic Cholecystectomy

Introducción: es bien sabido que el neumoperitoneo en cirugía laparoscópica afecta tanto al sistema cardiovascular como al sistema respiratorio, pero no se entiende por completo el grado en el que debemos modificar los parámetros ventilatorios para mini-mizar las complicaciones debido a la insuflación del neumoperitoneo. Estos cambios in-cluyen disminución de la distensibilidad y mayores presiones inspiratorias pico.

Abstract Background: it is well known that pneumoperitoneum in laparoscopic surgery affects both cardiovascular and respiratory system, but it is not fully understood yet the degree in which we have to make changes in the ventilatory settings to minimize the complica-tions due to insufflation of peritoneum, changes including impaired compliance and hig-her peak inspiratory.

Maximal respiratory pressures: Measurements at functional residual capacity in individuals with different health conditions using a digital manometer.

BACKGROUND: Measuring maximal respiratory pressure is a widely used method of investigating the strength of inspiratory and expiratory muscles. OBJECTIVES: To compare inspiratory pressures obtained at functional residual capacity (FRC) with measures at residual volume (RV), and expiratory pressures obtained at FRC with measures at total lung capacity (TLC) in individuals with different health conditions: post-COVID-19, COPD, idiopathic pulmonary fibrosis (IPF), heart failure (CHF), and stroke; and to compare the mean differences between measurements at FRC and RV/TLC among the groups. METHODS: Inspiratory and expiratory pressures were obtained randomly at different lung volumes. Mixed factorial analysis of covariance with repeated measures was used to compare measurements at different lung volumes within and among groups. RESULTS: Seventy-five individuals were included in the final analyses (15 individuals with each health condition). Maximal inspiratory pressures at FRC were lower than RV [mean difference (95% CI): 11.3 (5.8, 16.8); 8.4 (2.3, 14.5); 11.1 (5.5, 16.7); 12.8 (7.1, 18.4); 8.0 (2.6, 13.4) for COVID-19, COPD, IPF, CHF, and stroke, respectively] and maximal expiratory pressures at FRC were lower than TLC [mean difference (95% CI): 51.9 (37.4, 55.5); 60.9 (44.2, 77.7); 62.9 (48.1, 77.8); 58.0 (43.9, 73.8); 57.2 (42.9, 71.6) for COVID-19, COPD, IPF, CHF, and stroke, respectively]. All mean differences were similar among groups. CONCLUSION: Although inspiratory and expiratory pressures at FRC were lower than measures obtained at RV/TLC for the five groups of health conditions, the mean differences between measurements at different lung volumes were similar among groups, which raises the discussion about the influence of the viscoelastic properties of the lungs on maximal respiratory pressure.

Effects of high-intensity inspiratory muscle warm-up on inspiratory muscle strength and accessory inspiratory muscle activity.

This study aimed to determine the effects of work-matched moderate-intensity and high-intensity inspiratory muscle warm-up (IMW) on inspiratory muscle strength and accessory inspiratory muscle activity. Eleven healthy men performed three IMWs at different intensities, namely, placebo, moderate-intensity, and high-intensity, set, respectively, at 15 %, 40 %, and 80 % of maximal inspiratory mouth pressure (MIP). MIP was measured before and after IMW. Electromyography (EMG) was recorded for the sternocleidomastoid muscle (SCM) and intercostal muscles (IC) during IMW. MIP increased significantly in the moderate-intensity condition (104.2 ± 5.1 %, p < 0.05) and high-intensity condition (106.5 ± 6.2 %, p < 0.01) after IMW. The EMG amplitudes of the SCM and IC during IMW were significantly higher in the order of high-intensity, moderate-intensity, and placebo conditions. There was a significant correlation between changes in MIP and EMG amplitude of the SCM (r = 0.60, p < 0.01) and IC (r = 0.47, p < 0.01) during IMW. These findings suggest that high-intensity IMW increases neuromuscular activity in the accessory inspiratory muscles, which may improve inspiratory muscle strength.

A Prospective Study of 73 Patients to Compare Forward Head Angle, Forward Shoulder Angle, Maximal Inspiratory Pressure, and Self-Reported Breathing-Related Symptoms Before and After Open-Heart Surgery.

BACKGROUND Patients who undergo open-heart surgery often experience widespread musculoskeletal and pulmonary complications. These can interfere with their functioning, resulting in soft tissue changes, worsening postural changes, and poor respiratory performance. Therefore, the prospective study aimed to compare forward head angle (FHA) and forward shoulder angle (FSA), maximal inspiratory pressure (MIP), and self-reported breathing dysfunction before and after open-heart surgery. MATERIAL AND METHODS In a prospective observational study of 106 patients, men and women scheduled for open-heart surgery were enrolled. Prior to surgery and before discharge from the hospital, all patients were required to assess FHA and FSA using 2-dimensional motion analysis software, MIP using a respiratory pressure meter, and breathing dysfunction using the 25-item Self Evaluation of Breathing Questionnaire (SEBQ). Paired t test was used to compare differences between before and after surgery. To evaluate associations, logistic regression analysis was performed. RESULTS Of the 106 patients recruited, 73 completed the study. FHA (-Δ6.55±4.77, P.

Relationship between inspiratory muscle strength and balance in women: A cross-sectional study.

BACKGROUND: There is scarce evidence on changes at the functional level associated with the respiratory area in women. This study aims to analyse the relationship between inspiratory muscle strength and balance in women. MATERIAL AND METHODS: In this cross-sectional observational study, the sample consisted of groups according to the results obtained in the balance test. Inspiratory muscle weakness was defined as maximum inspiratory pressure (MIP) ≤ 80% of the predictive value. MIP was carried out using through a mouthpiece, with an electronic manometer. Logistic regression model was used to examine if MIP predicts balance. RESULTS: 159 women participated in the study. Approximately 20% of them achieved balance ≤ 2 seconds and 18% presented MIP≤80%. MIP was associated with the time achieved in the one-leg support test. Subjects with MIP ≤ 80% of the predictive value show 3 times more risk of having a lower performance in the balance test (OR = 3.26). CONCLUSIONS: Inspiratory muscle weakness is associated with deficient balance in this sample. It shows the need for multidimensional assessment and rehabilitation strategies for patients identified as having MIP weakness and/or balance disorders.

Inspiratory Muscle Training Improves Maximal Inspiratory Pressure Without Increasing Performance in Elite Swimmers.

PURPOSE: To analyze the effect of inspiratory muscle training (IMT) on the maximal inspiratory mouth pressure (MIP) and performance of elite swimmers. METHODS: Eight participants performed a 3000-m swimming test (T-3000), followed by blood lactate measurements at 1 and 5 minutes postexercise.. The testing protocol was carried out before and after 6 weeks of IMT, in which a high-volume IMT group (HV-IMT) (n = 4) performed IMT twice a day-in the morning in a seated position and in the afternoon in a concurrent session of IMT and core muscle training. Also, a low-volume IMT group (LV-IMT) (n = 4) performed IMT in the morning session only. RESULTS: After the intervention, both groups improved their MIP, HV-IMT (132.75 [27.42] to 156.75 [21.88] cmH2O; P = .010; d = 0.967) and LV-IMT (149.25 [22.82] to 171.50 [23.74] cmH2O; P = .013; d = 0.955), without a significant difference between groups (P = .855). Regarding swimming performance, there were no changes between groups in the T-3000 (P = .472) or lactate removal rate (P = .104). CONCLUSION: IMT increased inspiratory muscle strength in elite swimmers, but there was no association or meaningful impact on swimming performance.

Validation of the Single Breath Count Test for Assessment of Inspiratory Muscle Strength in Healthy Subjects and People with Neuromuscular Disorders.

OBJECTIVE: This study aimed to validate the single breath count test (SBCT) against volitional measures of respiratory muscle function in healthy subjects and people with neuromuscular disorders (NMD; n = 100 per group). METHODS: Testing comprised upright and supine SBCT, forced vital capacity (FVC), maximum inspiratory pressure (MIP), and sniff nasal inspiratory pressure (SNIP). Predictability of FVC by SBCT was assessed using logarithmic regression analysis. Receiver operating characteristics curves were used to identify SBCT thresholds for lung restriction (FVC < 80% predicted), inspiratory muscle weakness (MIP < 60 cmH2O), and indication for non-invasive ventilation (NIV) in NMD patients. RESULTS: In both groups, SBCT showed moderate correlation with FVC. In patients, SBCT values were also correlated with MIP and SNIP. Strength of correlations was similar with supine and upright SBCT which accounted for 23.7% of FVC variance in healthy individuals (44.5% in patients). Predictive thresholds of upright SBCT were < 27 for MIP < 60 cmH2O (sensitivity 0.61/specificity 0.86), <39 for NIV indication (0.92/0.46), and <41 for FVC < 80% predicted (0.89/0.62). CONCLUSION: The SBCT is positively correlated with spirometry. It predicts both lung restriction and NIV indication in NMD patients. The SBCT allows for remote monitoring and may substitute for spirometry/manometry if appropriate devices are unavailable.

New reference values for maximum respiratory pressures in healthy Brazilian children following guidelines recommendations: A regional study.

OBJECTIVE: To determine reference values for maximum static respiratory pressures in healthy children from a Brazilian region, following recommendations of the European Respiratory Society (ERS) and the Brazilian Society of Pneumology and Tisiology (SBPT). METHODS: A cross-sectional observational study was conducted with healthy children (6 to 11 years) of both sexes. The maximum inspiratory and expiratory pressures (PImax and PEmax, respectively) were measured using a digital manometer. Each child performed a minimum of three and a maximum of five maneuvers; three acceptable and reproducible maneuvers were considered for analysis. Minimum time for each maneuver was 1.5 seconds, with a one-second plateau, and one minute of rest between them. A stepwise multiple linear regression analysis was conducted for PImax and PEmax, considering correlations between independent variables: age, weight, and sex. RESULTS: We included 121 children (62 girls [51%]). Boys reached higher values for maximum respiratory pressures than girls. Respiratory pressures increased with age showing moderate effect sizes (PImax: f = 0.36; PEmax: f = 0.30) between the stratified age groups (6-7, 8-9, and 10-11 years). Age and sex were included in the PImax equation (PImax = 24.630 + 7.044 x age (years) + 13.161 x sex; R2 = 0.189). PEmax equations were built considering age for girls and weight for boys [PEmax (girls) = 55.623 + 4.698 x age (years) and PEmax (boys) = 82.617 + 0.612 x weight (kg); R2 = 0.068]. CONCLUSIONS: This study determined new reference equations for maximal respiratory pressures in healthy Brazilian children, following ERS and SBPT recommendations.

The respiratory effects of a Pilates method protocol: Randomized clinical trial.

OBJECTIVES: To evaluate the respiratory effects of a Pilates method (PM) protocol in adult women. DESIGN: Single-blind randomized controlled trial. SETTINGS: Healthy women were randomized into two groups using the Random.org online tool: a Pilates group (PG) (n = 33) and a control group (CG) (n = 29). PARTICIPANTS: Sixty-two healthy women, aged 18-44 years, sedentary or irregularly active B (as defined by the international physical activity questionnaire [IPAQ]). The intervention consisted of 16 sessions of PM. protocol twice a week for the PG. The CG without intervention. MAIN OUTCOMES MEASURES: The variables evaluated were maximal inspiratory pressure (MIP), maximal expiratory pressure (MEP), peak expiratory flow (PEF), tidal volume (TV), respiratory frequency (RF), minute volume (MV), and slow vital capacity (SVC). RESULTS: The results showed significant evidence of the beneficial respiratory effects of the PM protocol when the PG was compared with the CG: increased MIP (p = 0.001), and a significant increase in TV (p = 0,047). CONCLUSION: The PM protocol used in this study may be effective for respiratory muscle strength because it improved MIP and TV. CLINICAL TRIAL REGISTRATION: https://ensaiosclinicos.gov.br/rg/RBR-5b6wc3.