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.

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.

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.

Effect of pressure controlled volume guaranteed ventilation during pulmonary resection in children.

The purpose of the study was to evaluate the effect of pressure controlled volume guaranteed ventilation in children requiring one lung ventilation during pulmonary resection. Patients were randomly assigned to the lung protective ventilation combined with pressure controlled volume guaranteed group (PCV-VG group) or the lung protective ventilation combined with volume controlled ventilation group (VCV group). Both groups received tidal-volume ventilation of 8 ml kg-1 body weight during two lung ventilation and 6 ml kg-1 during OLV, with sustained 5 cmH2O positive end-expiratory pressure. Data collections were mainly performed at 10 min after induction of anaesthesia during TLV (T1), 5 min after OLV initiation (T2) and 5 min after complete CO2 insufflations (T3). In total, 63 patients were randomly assigned to the VCV (n = 31) and PCV-VG (n = 32) groups. The PCV-VG group exhibited lower PIP than the VCV group at T1 (16.8 ± 2.3 vs. 18.7 ± 2.7 cmH2O, P = 0.001), T2 (20.2 ± 2.7 vs. 22.4 ± 3.3 cmH2O, P = 0.001), and T3 (23.8 ± 3.2 vs. 26.36 ± 3.7 cmH2O, P = 0.01). Static compliance was higher in the PCV-VG group at T1, T2, and T3 (P = 0.01). After anaesthesia induction, lung aeration deteriorated, but with no immediate postoperative difference in both groups. Postoperative lung aeration improved and returned to normal from 2.5 h postextubation in both groups. PH was lower and PaCO2 was higher in VCV group than PCV-VG group during one lung ventilation. No differences were observed in PaO2-FiO2-ratio at T2 and T3, the incidence of postoperative pulmonary complications, intraoperative desaturation and the length of hospital stay. In paediatric patients, who underwent pulmonary resection requiring one lung ventilation, PCV-VG was superior to VCV in its ability to provide lower PIP, higher static compliance and lower PaCO2 at one lung ventilation during pneumothorax. However, its beneficial effects on different pathological situations in pediatric patients need more investigation.

Effects of home-based inspiratory muscle training on sickle cell disease (SCD) patients

ABSTRACT Introduction: Inspiratory muscle training (IMT) has been shown to be an efficient method of improving exercise tolerance and inspiratory and expiratory muscle strength in several diseases. The effects of IMT on patients with sickle cell anemia (SCD) are relatively unknown. Our study aimed to evaluate the effects of IMT on adult SCD patients, regarding respiratory muscle strength (RMS) variables, lung function, exercise tolerance, blood lactation concentration, limitation imposed by dyspnea during daily activities and impact of fatigue on the quality of life. Methods: This was a randomized single-blind study, with an IMT design comprising true load (TG) and sham load (SG) groups. Initial assessment included spirometry, volumetric capnography (VCap) and measurement of RMS by maximal inspiratory and expiratory pressure (PImax and PEmax). The Medical Research Council dyspnea scale and modified fatigue impact scale were also applied and blood lactate concentration was measured before and after the 6-minute walk test. After this initial assessment, the patient used the IMT device at home daily, returning every 6 weeks for RMS reassessment. Both groups used the same device and were unaware of which group they were in. After a period totaling 18 weeks, patients underwent the final evaluation, as initially performed. Results: Twenty-five patients in total participated until the end of the study (median age 42 years). There were no significant differences between TG and SG based on age, sex, body mass index or severity of genotype. At the end of the training, both groups showed a significant increase in PEmax and PImax, improvement in Vcap and in exercise tolerance and dyspnea reduction while performing daily life activities. The same was observed in patients grouped according to disease severity (HbSS and HbSβ0 vs HbSC and HbSβ+), without differences between groups. Conclusion: Home-based inspiratory muscle training benefits outpatients with SCD, including the sham load group. Trial registration:http://www.ensaiosclinicos.gov.br; registration number: RBR-6g8n92.

Respiratory muscle strength and exercise capacity of children and adolescents with chronic liver diseases / Força muscular respiratória e capacidade de exercício de crianças e adolescentes com hepatopatias crônicas

Introdution: Chronic liver diseases are characterized by inflammatory and fibrotic lesions of the liver that cause systemic complications. These complications can negatively interfere with the respiratory muscle strength and exercise capacity of developing children and adolescents. Objectives: to compare respiratory muscle strength and exercise capacity in children and adolescents with chronic hepatopathy, using predicted values from healthy individuals of the same age. Methodology: a cross-sectional study was performed. Children and adolescents from 6 to 16 years old with chronic hepatopathies were included. For the evaluation of respiratory muscle strength, the maximal respiratory pressures were measured through manovacuometry. A six-minute walk test was used to assess exercise capacity. The Wilcoxon test was used to verify the difference between the evaluated and predicted values of the distance traveled. Results: In total, 40 subjects were analyzed; 57.5% of the subjects were female, and the subjects had a mean age of 11.68±2.82 years. In the comparison between the measured and predicted maximal respiratory pressures, a median (IQR) difference of -21,47 (33-95) cmH2O (p< 0.001) was found for the maximal inspiratory pressure, and a mean difference of 30.68±17,16 cmH2O (p< 0.001) was found for the maximal expiratory pressure. Regarding exercise capacity, the measured average distance traveled was 346.46±49.21 m, which was 185.54±63,90 m (p< 0.001) less than the predicted value. Conclusion: Children and adolescents with chronic liver disease have reduced respiratory muscle function and exercise capacity.

Introdução: as doenças hepáticas crônicas são caracterizadas por lesões inflamatórias e fibróticas do fígado que causam complicações sistêmicas. Essas complicações podem interferir negativamente na força muscular respiratória e na capacidade de exercício de crianças e adolescentes em desenvolvimento. Objetivo: comparar a força muscular respiratória e a capacidade de exercício em crianças e adolescentes com hepatopatia crônica, utilizando valores preditos de indivíduos saudáveis da mesma idade. Metodologia: trata-se de um estudo transversal. Foram incluídas crianças e adolescentes de 6 a 16 anos com hepatopatias crônicas. Para a avaliação da força muscular respiratória, as pressões respiratórias máximas foram medidas por meio da manovacuometria. Teste de caminhada de seis minutos foi usado para avaliar a capacidade de exercício. O teste de Wilcoxon foi utilizado para verificar a diferença entre os valores avaliados e previstos da distância percorrida. Resultados: no total, 40 sujeitos foram analisados; 57,5% dos sujeitos eram do sexo feminino, idade média de 11,68±2,82 anos. Na comparação entre as pressões respiratórias máximas medidas e previstas, foi encontrada diferença mediana (IQ) de -21,47 (33-95) cmH2O (p<0,001) para a pressão inspiratória máxima e diferença média de 30,68±17,16 cmH2O (p<0,001) para a pressão expiratória máxima. Em relação à capacidade de exercício, a distância média percorrida foi 346,46±49,21 m, média 185,54±63,90 m (p<0,001) inferior ao valor previsto. Conclusão: crianças e adolescentes com doença hepática crônica apresentam redução da função muscular respiratória e da capacidade de exercício.

Inspiratory Muscle Weakness is Related to Poor Short-Term Outcomes for Heart Transplantation

Abstract Introduction: In heart transplantation (HT) recipients, several factors are critical to promptly adopting appropriate rehabilitation strategies and may be important to predict outcomes way after surgery. This study aimed to determine preoperative patient-related risk factors that could adversely affect the postoperative clinical course of patients undergoing HT. Methods: Twenty-one hospitalized patients with heart failure undergoing HT were evaluated according to respiratory muscle strength and functional capacity before HT. Mechanical ventilation (MV) time, reintubation rate, and intensive care unit (ICU) length of stay were recorded, and assessed postoperatively. Results: Inspiratory muscle strength as absolute and percentpredicted values were strongly correlated with MV time (r=-0.61 and r=-0.70, respectively, at P<0.001). Concerning ICU length of stay, only maximal inspiratory pressure (MIP) absolute and percent-predicted values were significantly associated. The absolute -MIP- was significantly negatively correlated with ICU length of stay (r=-0.58 at P=0.006) and the percent-predicted MIP was also significantly negatively correlated with ICU length of stay (r=-0.68 at P=0.0007). No associations were observed between preoperative functional capacity, age, sex, and clinical characteristics and MV time and ICU length of stay in the cohort included in this study. Patients with respiratory muscle weakness had a higher prevalence of prolonged MV, reintubation, and delayed ICU length of stay. Conclusion: An impairment of preoperative MIP was associated with poorer short-term outcomes following HT. As such, inspiratory muscle strength is an important clinical preoperative marker in patients undergoing HT.

Pressões respiratórias máximas em indivíduos obesos antes e após cirurgia bariátrica / Maximum respiratory pressure in obese individuals before and after bariatric surgery

A obesidade é uma doença crônica e multifatorial que leva a alterações sistêmicas e é considerada um problema de saúde pública mundial. Entre as alterações respiratórias decorrentes da obesidade se discute como o ganho de peso ou a perda deste pode interferir nas pressões respiratórias máximas (PRM), não existindo consenso na literatura. Objetivo: Analisar o poder preditivo das equações de referência para PMR em obesos antes e após perda de peso. Métodos: Estudo transversal no qual foram incluídos vinte pacientes obesos dos Programas de Cirurgia Bariátrica de hospitais de referência em Manaus/Amazonas, que tiveram as PRM avaliadas por meio de manuvacuometria antes e aproximadamente um ano e meio após a cirurgia bariátrica. Resultados: O peso médio diminuiu de 138,5 ± 21,7 kg para 82,7 ± 8,2 kg após a cirurgia. As PRM foram supranormais antes da cirurgia e reduzidas após a cirurgia. Entre as equações analisadas, apenas as propostas por Sanchez et al. foram capazes de predizer os valores medidos. Conclusão: As PRM foram aumentadas nos obesos mórbidos avaliados e reduzidas após a cirurgia. As equações mais utilizadas na prática clínica brasileira parecem não ser capazes de predizer valores de PRM nessa população, sendo as mais adequadas as propostas por Sanchez et al. (AU)

Obesity is a chronic and multifactorial disease and is considered a global public health problem. Among the respiratory changes due to obesity, weight gain or loss of body weight can interfere with maximal respiratory pressures, and there is no consensus in the literature. Objective: To analyze the predictive power of the reference equations for maximal respiratory pressures in obese before and after weight loss. Methods: A crosssectional study was carried out in which 20 obese patients were included in the Bariatric Surgery Programs of reference hospitals in Manaus/Amazonas. The maximal respiratory pressures were assessed by manuvacuometry before and approximately one year after bariatric surgery. Results: The mean weight decreased from 138.5 ± 21.7 kg to 82.7 ± 8.2 kg after surgery. The maximal respiratory pressures were supranormal before surgery and reduced after surgery. Among the analyzed equations, only those proposed by Sanchez et al. were able to predict the measured values. Conclusion: The maximal respiratory pressures were increased in the morbidly obese evaluated and reduced after the surgery. The most used equations in Brazilian clinical practice seem not to be able to predict maximal respiratory pressures values in this population, being the most adequate those proposed by Sanchez et al. (AU)

Uso da eletromiografia de superfície na resultância do treinamento muscular inspiratório com carga linear em portadores do vírus linfotrópico humano tipo 1 / Use of surface electromyography in results of inspiratory muscle training with linear load in patients with type 1 human lymphotropic virus

Este estudo visa avaliar por eletromiografia de superfície o comportamento dos músculos inspiratórios no treinamento muscular em voluntários com vírus linfotrópico de célula T humana do tipo 1. Trata-se de um ensaio clínico. Sete voluntários, com idade 58,85 ± 7,2) anos, realizaram treinamento muscular inspiratório domiciliar por 4 semanas, 3 vezes por semana, 30 minutos diários por meio de incentivador de carga linear. Para avaliação utilizou-se os dados de pressão inspiratória máxima e os dados da eletromiografia de superfície nas fases pré (T0), segunda semana (T2) e após a quarta semana (T4) de treinamento. Observou-se aumento progressivo da força muscular inspiratória de T0 a T4 (p = 0,007), assim como, aumento do recrutamento das unidades motoras pela análise da amplitude do sinal eletromiográfico, sendo mais evidente para o músculo esternocleidomastóideo (p = 0,12) em comparação ao músculo diafragma (p = 0,6). Verificou-se que no decurso do treinamento muscular ocorreu melhora significativa da força muscular inspiratória com maior recrutamento das fibras musculares dos músculos analisados na amostra. (AU)

This study aimed to evaluate by surface electromyography the behavior of inspiratory muscles in the muscle training of volunteers with human T-cell lymphotropic virus type 1. This was a clinical trial. Seven volunteers, 58,85 ± 7.21 years old, underwent inspiratory muscle training at home for 4 weeks, 3 times a week, 30 minutes daily by means of a linear load stimulator. The maximum inspiratory pressure data and the surface electromyography data were used for evaluation in the pre (T0), second week (T2) and after the fourth week (T4) training phases. There was a progressive increase in inspiratory muscle strength from T0 to T4 (p = 0.007), as well as an increase in the recruitment of motor units by analyzing the amplitude of the electromyographic signal, being more evident for the sternocleidomastoid muscle (p = 0.12) in comparison to the diaphragm muscle (p = 0.6). During the muscle training inspiratory muscle strength improves with greater recruitment of muscle fibers from the muscles analyzed in the sample. (AU)

Use of volume controlled vs. pressure controlled volume guaranteed ventilation in elderly patients undergoing laparoscopic surgery with laryngeal mask airway.

BACKGROUND: The peak inspiratory pressure (PIP) is crucial in mechanical ventilation with supraglottic airway device (SAD). Pressure-controlled ventilation volume-guaranteed (PCV-VG), delivering a preset tidal volume with the lowest required airway pressure, is being increasingly used during general anesthesia. In this study, we compared respiratory mechanics and circulatory parameters between volume-controlled ventilation (VCV) and PCV-VG in elderly patients undergoing laparoscopic surgery using the laryngeal mask airway supreme (LMA). METHODS: Eighty participants scheduled for laparoscopic surgery were enrolled in this prospective, randomized clinical trial. The participants were randomly assigned to receive VCV or PCV-VG. PIP, dynamic compliance (Cdyn) and mean inspiratory pressure (Pmean) were recorded at 5 min after induction of anesthesia (T1), 5 min after pneumoperitoneum(T2), 30 and 60 min after pneumoperitoneum (T3 and T4). Data including other respiratory variables, hemodynamic variables, and arterial blood gases were also collected. The difference in PIP between VCV and PCV-VG was assessed as the primary outcome. RESULTS: PIP was significantly lower at T2, T3, and T4 in both groups compared with T1 (all P <  0.0001), and it was significantly lower in the PCV-VG group than the VCV group at T2, T3, and T4 (all P <  0.001). Cydn was decreased at T2, T3, and T4 in two groups compared with T1 (all P <  0.0001), but it was higher in PCV-VG group than in VCV group at T2, T3, and T4 (all P <  0.0001). There were on statistically significant differences were found between the groups for other respiratory and hemodynamic variables. CONCLUSION: In elderly patients who underwent laparoscopic surgery using an LMA, PCV-VG was superior to VCV in its ability to provide ventilation with lower peak inspiratory pressure and greater dynamic compliance.

How Many Maneuvers Should We Do for Maximal Inspiratory and Expiratory Muscle Pressure Testing in Children: A Retrospective Review in Children with Cystic Fibrosis.

OBJECTIVES: Maximal inspiratory pressure (MIP) and maximal expiratory pressure (MEP) could be useful clinical parameters in monitoring many conditions including cystic fibrosis (CF). However, current protocols for undertaking the measurements lack standardization including the number of repeated attempts to achieve best values. We aimed to (a) determine the optimum number of attempts to achieve best MIP/MEP values, and (b) evaluate if the number of attempts is consistent across two different test days. METHODS: We analyzed data of a previous randomized controlled trial involving the effect of singing on respiratory muscle strength in 35 children with CF. On two different days (T1, T2) children performed MIP/MEP with at least ten attempts each to achieve < 10% repeatability. RESULTS: All children achieved repeatable MIP/MEP values within 10-11 attempts with 24 (68.6%) and 26 (74.3%) of these achieving best values of MIP and MEP, respectively, at attempts 6-11. Median values of the pressures by three, five, eight and all attempts significantly increased with more attempts (all p < 0.05). At T2, 56% required fewer attempts to achieve best values, but 32% required more attempts, indicating that the number of attempts required was inconsistent between test days. CONCLUSION: It is likely that at least ten attempts (best two within < 10% variability) is required to achieve best and reliable MIP/MEP in children with CF. A larger sample size in children with CF and various conditions is required to consolidate these findings.

Effects of Inspiratory Muscle Training Using an Electronic Device on Patients Undergoing Cardiac Surgery: A Randomized Controlled Trial

Abstract Background Cardiac surgery causes pathophysiological changes that favor the occurrence of pulmonary and functional complications. Objective To investigate the effects of inspiratory muscle training (IMT) with an electronic device on patients undergoing cardiac surgery. Methods A randomized controlled trial was conducted with 30 adult patients undergoing elective cardiac surgery. A control group (CG) received conventional physical therapy care, and an intervention group (IG) received IMT using the POWERbreathe K5® electronic device. Two daily sessions of physical therapy were performed at the intensive care unit and one daily session at the ward until the sixth postoperative day. The following variables were measured preoperatively and on the sixth postoperative day, in both groups: inspiratory muscle strength, dynamic inspiratory muscle strength, and peak inspiratory flow. Data distribution was evaluated by the Shapiro-Wilk test. Analysis of variance was used, and the results were considered statistically significant when p < 0.05. Results Maximal inspiratory pressure (71.7 ± 17.1 cmH2O vs 63.3 ± 21.3 cmH2O; p = 0.11], S-index (52.61 ± 18.61 vs 51.08 ± 20.71), and peak inspiratory flow [(2.94 ± 1.09 vs 2.79 ± 1.26)] were maintained in the IG but had a significant reduction in the CG. Conclusion IMT performed with an electronic device was effective at maintaining inspiratory muscle strength, dynamic inspiratory muscle strength, and peak inspiratory flow when compared to conventional physical therapy. Int J Cardiovasc Sci. 2020; [online].ahead print, PP.0-0

Inspiratory Muscle Weakness is Related to Poor Short-Term Outcomes for Heart Transplantation.

INTRODUCTION: In heart transplantation (HT) recipients, several factors are critical to promptly adopting appropriate rehabilitation strategies and may be important to predict outcomes way after surgery. This study aimed to determine preoperative patient-related risk factors that could adversely affect the postoperative clinical course of patients undergoing HT. METHODS: Twenty-one hospitalized patients with heart failure undergoing HT were evaluated according to respiratory muscle strength and functional capacity before HT. Mechanical ventilation (MV) time, reintubation rate, and intensive care unit (ICU) length of stay were recorded, and assessed postoperatively. RESULTS: Inspiratory muscle strength as absolute and percentpredicted values were strongly correlated with MV time (r=-0.61 and r=-0.70, respectively, at P<0.001). Concerning ICU length of stay, only maximal inspiratory pressure (MIP) absolute and percent-predicted values were significantly associated. The absolute |MIP| was significantly negatively correlated with ICU length of stay (r=-0.58 at P=0.006) and the percent-predicted MIP was also significantly negatively correlated with ICU length of stay (r=-0.68 at P=0.0007). No associations were observed between preoperative functional capacity, age, sex, and clinical characteristics and MV time and ICU length of stay in the cohort included in this study. Patients with respiratory muscle weakness had a higher prevalence of prolonged MV, reintubation, and delayed ICU length of stay. CONCLUSION: An impairment of preoperative MIP was associated with poorer short-term outcomes following HT. As such, inspiratory muscle strength is an important clinical preoperative marker in patients undergoing HT.

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.

Heart Failure Results in Inspiratory Muscle Dysfunction Irrespective of Left Ventricular Ejection Fraction.

BACKGROUND: Exercise intolerance in heart failure with reduced ejection fraction (HFrEF) or heart failure with preserved ejection fraction (HFpEF) results from both cardiac dysfunction and skeletal muscle weakness. Respiratory muscle dysfunction with restrictive ventilation disorder may be present irrespective of left ventricular ejection fraction and might be mediated by circulating pro-inflammatory cytokines. OBJECTIVE: To determine lung and respiratory muscle function in patients with HFrEF/HFpEF and to determine its associations with exercise intolerance and markers of systemic inflammation. METHODS: Adult patients with HFrEF (n = 22, 19 male, 61 ± 14 years) and HFpEF (n = 8, 7 male, 68 ± 8 years) and 19 matched healthy control subjects underwent spirometry, measurement of maximum mouth occlusion pressures, diaphragm ultrasound, and recording of transdiaphragmatic and gastric pressures following magnetic stimulation of the phrenic nerves and the lower thoracic nerve roots. New York Heart Association (NYHA) class and 6-min walking distance (6MWD) were used to quantify exercise intolerance. Levels of circulating interleukin 6 (IL-6) and tumor necrosis factor-α (TNF-α) were measured using ELISAs. RESULTS: Compared with controls, both patient groups showed lower forced vital capacity (FVC) (p < 0.05), maximum inspiratory pressure (PImax), maximum expiratory pressure (PEmax) (p < 0.05), diaphragm thickening ratio (p = 0.01), and diaphragm strength (twitch transdiaphragmatic pressure in response to supramaximal cervical magnetic phrenic nerve stimulation) (p = 0.01). In patients with HFrEF, NYHA class and 6MWD were both inversely correlated with FVC, PImax, and PEmax. In those with HFpEF, there was an inverse correlation between amino terminal pro B-type natriuretic peptide levels and FVC (r = -0.77, p = 0.04). In all HF patients, IL-6 and TNF-α were statistically related to FVC. CONCLUSIONS: Irrespective of left ventricular ejection fraction, HF is associated with respiratory muscle dysfunction, which is associated with increased levels of circulating IL-6 and TNF-α.

Respiratory muscle impairment evaluated with mep/mip ratio in children and adolescents with chronic respiratory disease / Fraqueza muscular respiratória avaliada por meio da relação pemax/pimax em crianças com doença respiratória crônica

ABSTRACT Objective: To evaluate the strength of respiratory muscles and to compare maximum inspiratory (MIP) and expiratory (MEP) pressure and MEP/MIP ratio between patients with chronic respiratory diseases and healthy individuals. Methods: Case-control study. Individuals with neuromuscular disease and post-infectious bronchiolitis obliterans were considered. In addition, they were also matched according to anthropometric and demographic characteristics with healthy children and adolescents. MIP, MEP in the three groups, and pulmonary function only in patients with chronic respiratory diseases were recorded. Results: A total of 52 subjects with CRD (25 with neuromuscular disease, and 27 with post-infectious bronchiolitis obliterans) and 85 healthy individuals were included, with an average age of 11.3±2.1 years. Patients with neuromuscular disease and post-infectious bronchiolitis obliterans presented lower MIP and MEP when compared with healthy individuals, although MEP/MIP ratio was lower in patients with neuromuscular disease (0.87±0.3) and higher in patients with post-infectious bronchiolitis obliterans (1.1±0.3) compared to the healthy group (0.97±0.2). Only in patients with neuromuscular disease a negative correlation was observed between MEP/MIP ratio and age (r=-0.50; p=0.01). Conclusions: Differences in the pattern of muscular weakness between patients with chronic respiratory diseases were observed. In patients with neuromuscular disease, a decrease in the MEP/MIP ratio depending on MIP was verified; and in those patients with post-infectious bronchiolitis obliterans, an increase in the MEP/MIP ratio depending on MIP was also observed.

RESUMO Objetivo: Avaliar a força dos músculos respiratórios e comparar a relação entre a pressão expiratória máxima (PEmáx) e a pressão inspiratória máxima (PImáx) em pacientes com doença respiratória crônica (DRC) e crianças saudáveis. Métodos: Estudo caso-controle. Foram selecionados indivíduos com doença neuromuscular e bronquiolite obliterante pós-infecciosa. Ademais, os grupos foram pareados com crianças e adolescentes saudáveis, considerando características antropométricas e demográficas. Foram registradas a PImáx e a PEmáx nos três grupos e a função pulmonar apenas em pacientes com doença respiratória crônica. Resultados: Foram incluídos 52 indivíduos com DRC (25 com doença neuromuscular e 27 com bronquiolite obliterante pós-infecciosa) e 85 indivíduos saudáveis, com idade média de 11,3±2,1 anos. Pacientes com doença neuromuscular e bronquiolite obliterante pós-infecciosa apresentaram menor PImáx e PEmáx em comparação aos indivíduos saudáveis, embora a relação PEmáx/PImáx tenha sido menor nos pacientes com doença neuromuscular (0,87±0,3) e maior nos pacientes com bronquiolite obliterante pós-infecciosa (1,1±0,3) em comparação ao grupo saudável (0,97±0,2). Somente em pacientes com doença neuromuscular foi observada uma correlação negativa entre a razão PEmáx/PImáx e a idade (r=-0,50; p=0,01). Conclusões: Foram observadas diferenças no padrão de fraqueza muscular em pacientes com doença respiratória crônica. Nos pacientes com doença neuromuscular, verificou-se diminuição na relação PEmáx/PImáx dependendo da PImáx; em pacientes com bronquiolite obliterante pós-infecciosa, foi observado aumento na relação dependendo da PImáx.

Inspiratory muscle training based on anaerobic threshold on the functional capacity of patients after coronary artery bypass grafting: clinical trial

Abstract Introduction: Coronary artery bypass grafting (CABG) is associated with reduced ventilatory muscle strength and consequent worsening of functional capacity (FC). Inspiratory Muscle Training (IMT) can be indicated, but there is still a lack of knowledge about the use of the anaerobic threshold (AT) as a basis for prescription. The objective of this study is to evaluate if IMT based on AT modifies FC and inspiratory muscle strength of patients submitted to CABG. Methods: This is a clinical trial. On the first postoperative day, the patients were divided into two groups: the conventional group (IMT-C), which performed IMT based on 40% of maximal inspiratory pressure (MIP), and the IMT-AT group, which performed IMT based on AT. All patients underwent preoperative and postoperative assessment of MIP and performed a six-minute walk test (6MWT). Results: Forty-two patients were evaluated, 21 in each group. Their mean age was 61.4±10 years and 27 (64%) of them were male. There was a reduction of inspiratory muscle strength with a delta of 23±13 cmH2O in the IMT-C group vs. 11±10 cmH2O in the IMT-AT group (P<0.01) and of the walking distance with a delta of 94±34 meters in the IMT-C group vs. 57±30 meters in the IMT-AT group (P=0.04). Conclusion: IMT based on AT minimized the loss of FC and inspiratory muscle strength of patients submitted to CABG.

Comparison of volume-controlled, pressure-controlled, and pressure-controlled volume-guaranteed ventilation during robot-assisted laparoscopic gynecologic surgery in the Trendelenburg position.

Background: Pressure-controlled ventilation volume-guaranteed (PCV-VG) is being increasingly used for ventilation during general anesthesia. Carbon dioxide (CO2) pneumoperitoneum in the Trendelenburg position is routinely used during robot-assisted laparoscopic gynecologic surgery. Here, we hypothesized that PCV-VG would reduce peak inspiratory pressure (Ppeak), compared to volume-controlled ventilation (VCV) and pressure-controlled ventilation (PCV). Methods: In total, 60 patients were enrolled in this study and randomly assigned to receive VCV, PCV, or PCV-VG. Hemodynamic variables, respiratory variables, and arterial blood gases were measured in the supine position 15 minutes after the induction of anesthesia (T0), 30 and 60 minutes after CO2 pneumoperitoneum and Trendelenburg positioning (T1 and T2, respectively), and 15 minutes after placement in the supine position at the end of anesthesia (T3). Results: The Ppeak was higher in the VCV group than in the PCV and PCV-VG groups (p=0.011). Mean inspiratory pressure (Pmean) was higher in the PCV and PCV-VG groups than in the VCV group (p<0.001). Dynamic lung compliance (Cdyn) was lower in the VCV group than in the PCV and PCV-VG groups (p=0.001). Conclusion: Compared to VCV, PCV and PCV-VG provided lower Ppeak, higher Pmean, and improved Cdyn, without significant differences in hemodynamic variables or arterial blood gas results during robot-assisted laparoscopic gynecologic surgery with Trendelenburg position.

Inspiratory Muscle Training Based on Anaerobic Threshold on the Functional Capacity of Patients After Coronary Artery Bypass Grafting: Clinical Trial.

INTRODUCTION: Coronary artery bypass grafting (CABG) is associated with reduced ventilatory muscle strength and consequent worsening of functional capacity (FC). Inspiratory Muscle Training (IMT) can be indicated, but there is still a lack of knowledge about the use of the anaerobic threshold (AT) as a basis for prescription. The objective of this study is to evaluate if IMT based on AT modifies FC and inspiratory muscle strength of patients submitted to CABG. METHODS: This is a clinical trial. On the first postoperative day, the patients were divided into two groups: the conventional group (IMT-C), which performed IMT based on 40% of maximal inspiratory pressure (MIP), and the IMT-AT group, which performed IMT based on AT. All patients underwent preoperative and postoperative assessment of MIP and performed a six-minute walk test (6MWT). RESULTS: Forty-two patients were evaluated, 21 in each group. Their mean age was 61.4±10 years and 27 (64%) of them were male. There was a reduction of inspiratory muscle strength with a delta of 23±13 cmH2O in the IMT-C group vs. 11±10 cmH2O in the IMT-AT group (P<0.01) and of the walking distance with a delta of 94±34 meters in the IMT-C group vs. 57±30 meters in the IMT-AT group (P=0.04). CONCLUSION: IMT based on AT minimized the loss of FC and inspiratory muscle strength of patients submitted to CABG.