Mean Maximal Inspiratory Pressure Research Articles

"Inspiratory muscle weakness in acutely hospitalized patients 75years and over": a secondary analysis of a randomized controlled trial on the effectiveness of multicomponent exercise and inspiratory muscle training.

The impact of hospitalization for acute illness on inspiratory muscle strength in oldest-old patients is largely unknown, as are the potential benefits of exercise and inspiratory muscle training (IMT) during in-hospital stay. This was a sub-study of a randomized clinical trial that evaluated the efficiency of a multicomponent exercise program in preventing hospitalization-associated disability. Patients were randomized into control (CG) and intervention (IG) groups. The intervention included two daily sessions of supervised walking, squat, balance, and IMT. Baseline and discharge maximal inspiratory pressure (MIP) and inspiratory muscle weakness (IMW) were determined. The effect of the intervention on inspiratory muscle strength was assessed by analyzing (1) the differences between groups in baseline and discharge MIP and IMW, (2) the association, patient by patient, between baseline and discharge MIP, and the improvement index (MIP discharge/baseline) in patients with or without IMW. In total, 174 patients were assessed (mean age of 87), 57 in CG and 117 in IG. Baseline MIP was lower than predicted in both sexes (women 29.7 vs 44.3; men 36.7 vs 62.5 cmH2O, P < 0.001, baseline vs predicted, respectively). More than 65% of patients showed IMW at admission. In women in IG, the mean MIP was higher at discharge than at admission (P = 0.003) and was the only variable that reached expected reference levels at discharge (Measured MIP 39.2 vs predicted MIP 45 cmH2O, P = 0.883). Patients with IMW on admission showed a statistically significant improvement in MIP after the intervention. IMW is very prevalent in oldest-old hospitalized with acute illness. Patients might benefit from a multicomponent exercise program including IMT, even during short-stay hospitalization. ClinicalTrials.gov; No.: NTC03604640. May 3, 2018.

Role of the Inspiratory Muscles on Functional Performance From Critical Care to Hospital Discharge and Beyond in Patients With COVID-19.

The role of inspiratory muscle performance in functional performance in patients with coronavirus disease 2019 (COVID-19) is poorly understood. The purpose of this study was to perform a longitudinal examination of inspiratory and functional performance from intensive care unit (ICU) discharge (ICUD) to hospital discharge (HD) and symptoms at HD and 1month after HD in patients with COVID-19. Thirty patients (19 men, 11 women) with COVID-19 were included. Examination of inspiratory muscle performance at ICUD and HD was performed with an electronic manometer, which provided the maximal inspiratory pressure (MIP) and several other inspiratory measures. Examination of dyspnea and functional performance was performed at ICUD and HD with the Modified Borg Dyspnea Scale and the 1-minute sit-to-stand test (1MSST), respectively. The mean age was 71 (SD = 11) years, the mean length of ICU stay was 9 (SD = 6) days, and the mean length of hospital stay was 26 (SD = 16) days. Most of the patients were diagnosed with severe COVID-19 (76.7%) and had a mean Charlson Comorbidity Index of 4.4 (SD = 1.9), reflecting high comorbidity. The mean MIP of the entire cohort increased minimally from ICUD to HD (from 36 [SD = 21] to 40 [SD = 20] cm H2O), reflecting predicted values for men and women at ICUD and HD of 46 (25%) to 51 (23%) and 37 (24%) to 37 (20%), respectively. The 1MSTS score increased significantly from ICUD to HD (9.9 [SD = 7.1] vs 17.7 [SD = 11.1]) for the entire cohort but remained far below population-based reference values (2.5th percentile) for the majority of patients at ICUD and HD. At ICUD, MIP was found to be a significant predictor of a favorable change in 1MSTS performance (β = 0.308; odds ratio = 1.36) at HD. A significant reduction in inspiratory and functional performance exists in patients with COVID-19 at both ICUD and HD, with a greater MIP at ICUD being a significant predictor of a greater 1MSTS score at HD. This study shows that inspiratory muscle training may be an important adjunct after COVID-19.

Respiratory function of children and adolescents with osteogenesis imperfecta: respiratory muscle strength, forced vital capacity, and peak expiratory flow.

This study aims to evaluate the respiratory function of children and adolescents with osteogenesis imperfecta (OI) followed up at a referral center. A cross-sectional study was conducted with a non-probabilistic sample. Manovacuometry was performed with the measurement of maximal inspiratory pressure (MIP) and maximal expiratory pressure (MEP), and in addition, peak expiratory flow (PEF) and ventilometry were performed to measure forced vital capacity (FVC). In total, 23 individuals were evaluated, with a mean age of 11.6±3.4 years, 56.5% of whom were females. Regarding the classification of OI, 56.5% of the sample belonged to type IV, 30.5% to type III, and 13% to type I. The mean MIP was 64.4% of the predicted, and the mean MEP was 56.2% of the predicted. Overall, the mean PEF was 213.9 L/min, but only 140.6 L/min in the OI type III group. Median FVC was 1.9 L, corresponding to 110% of the predicted. Respiratory function of the study subjects was altered, with respiratory muscle strength values lower than expected in the whole sample, and peak expiratory flow was significantly reduced in the OI type III group.

Maximal Inspiratory and Expiratory Pressures in Men with Chronic Obstructive Pulmonary Disease: A Cross-Sectional Study

Introduction: Respiratory muscle dysfunction is a cardinal feature in chronic obstructive pulmonary disease (COPD) contributing to decreased exercise capacity and pulmonary function test (PFT) limitation with progression of the disease. Maximal inspiratory pressure (MIP) and maximal expiratory pressure (MEP) are reliable parameters for assessing the respiratory muscle strength. Aims: This study aims to measure maximal inspiratory and expiratory pressures in male COPD patients, to determine their correlates, and to study the relationship between the severity of COPD and respiratory muscle strength. Patients and Methods: This was an observational, cross-sectional study. A total of 100 males, who were known COPD patients and who were clinically stable, were recruited. Both inpatients and outpatients were studied. Spirometric PFT test was done, and MIP and MEP were measured using respiratory pressure meter. Descriptive statistics and Pearson's correlation were used. Results: The mean (± standard deviation) MIP and MEP were 47.73 (±19.6) cm H2O and 60.76 (±11.6) cm H2O, respectively. MIP and MEP showed a highly significant correlation (P

NO RELATIONSHIP BETWEEN PULMONARY FUNCTION AND EXERCISE CAPACITY IN PEOPLE WITH POSTACUTE SEQUELAE OF SARS-COV-2 INFECTION

NO RELATIONSHIP BETWEEN PULMONARY FUNCTION AND EXERCISE CAPACITY IN PEOPLE WITH POSTACUTE SEQUELAE OF SARS-COV-2 INFECTION

Prediction for the maximum inspiratory pressure value from the thoracic expansion measurement in Indonesian healthy young adults.

BackgroundThe diaphragm is the primary muscle responsible for breathing. Weakness in the diaphragm will result in breathing difficulties. The micro-RPM (respiratory pressure meter) is a non-invasive testing device to measure respiratory muscle strength, which is not always feasible, while thoracic expansion measurements are easy to do.AimThis study constructs a prediction formula for a maximal inspiratory pressure (MIP) value from thoracic expansion measurements.MethodsThis study was quantitative with a cross-sectional design. Participants were healthy adults aged 20–40 years, with normal Mini-Mental State Examinations, body mass index, spirometry, and moderate activity levels. The tests performed were MIP and thoracic expansion measurements at three levels: axilla (L1), the fourth intercostal space (L2), and at processus xiphoideus (L3). The data were analyzed using an unpaired t-test and multivariate.ResultsThe mean MIP for males (81.51 ± 13.90 cmH2O) was significantly greater than females (63.17 ± 15.89 cmH2O) (P = 0.0001). These findings were not different with the Chinese, Indian, Mangalorean, and Malaysian populations because they are all of Asian ethnicity. Thoracic expansion L2 (r = 0.463, P = 0.0001) and L3 (r = 0.502, P = 0.0001) were moderately correlated with MIP, whereas thoracic expansion L2, L3 combined with gender had a weak effect on MIP. The prediction formula was: MIP = 56.802 + 2.387 + L2 + 13.904 + Gender * and MIP = 53.289+ 3.561 + L3 + 9.504 + Gender *, * 0 = female; 1 = male.ConclusionsA prediction formula for MIP can be made using the thoracic expansion variable with gender as a determinant factor. A quick and easy measurement of thoracic expansion can be used as a mean of screening respiratory muscle strength in patient care.

Respiratory Muscle Strength in Healthy Indian Children of Age 7-17 Years: A Cross-Sectional Study.

PurposeAs the values of respiratory muscle strength vary according to race, ethnicity, and geographical area, there is a wide-ranging difference among different populations. Thus, the available reference values may not have an application for use in the Indian paediatric population, creating a need for generating values which will be appropriate for the Indian paediatric context.Materials and MethodsAssessment of respiratory muscle strength was carried out by assessing maximal inspiratory pressure (MIP) and maximal expiratory pressure (MEP) and synthesising predictive formulas using anthropometric variables like height, gender and age, which will be suitable for Indian children.ResultsWe calculated MIP and MEP of 320 (boys=160 and girls= 160) children in the age range of 7 years to 17 years of Mangaluru city, India. Results stated that mean MIP and MEP for boys were 72.5±32.8 cm H2O and 73±33.2 cm H2O, while for the girls it was 67±30.2 cm H2O and 68±30.1 cm H2O, respectively.ConclusionThis study concluded that there is a difference in respiratory pressure values of Indian children with respect to those of other countries. Age, gender, height and BMI have a significant role in determining respiratory muscle strength. Boys demonstrated higher MIP and MEP. As age, height, weight and BMI increases, so does MIP and MEP.

Differences in maximal inspiratory pressure when using a standard yoga mat versus a standard yoga block in healthy individuals

Background Yoga, which incorporates posture optimisation and specific breathing techniques, is recognised for its health benefits including musculoskeletal strengthening, stress relief and respiratory enhancement. It is therefore becoming an increasingly utilised practice within the medical environment, specifically for those with respiratory dysfunctions such as chronic obstructive pulmonary disease (COPD). The relationship between posture and yoga and the potential impact upon breathing is an important topic to study for its potential health benefits. This study compares the impact of two different yoga seating positions on respiratory muscle strength. Methodology Eighteen students from Cardiff University between the ages of 19–34 years were recruited via convenience sampling. Each was in good health, with body mass index (BMI) in the normal category and possessed no respiratory infection or significant spinal deformities. Participants were required to sit comfortably, cross-legged for 2 minutes in each sitting position, before three measurements of maximal inspiratory pressure (MIP) were taken. Analysis was performed on the highest result in each position using Statistical Package for the Social Sciences (SPSS) version 25. Comments on comfort levels were given spontaneously and, despite not being a primary aim of the study, provided an interesting discussion point. Results and conclusions Sitting on a yoga mat produced higher mean MIP figures (104cm H2O) than the yoga block (100.39cm H2O), p = 0.015. Despite statistical significance, the mean difference of 3.61cm H2O is unlikely to have clinical significance as it is small compared to the observed MIP range (&gt;90 cm H2O). There does not appear to be a recognised minimum clinically important difference in the literature, making interpretation difficult.

Efficacy of Incentive Spirometry in Expiratory Muscle Training Following Abdominal Surgery

BACKGROUND: Incentive spirometry is a device which helps in the improvement of lung function after abdominal surgery. It motivates the patients by giving visual feedback about their lung volumes. It is one of the less expensive and user-friendlydevices. Incentive spirometry facilitates the patients to take slow deep breath and there by producing a sustained maximal inspiration (SMI) that mainly helps in the prevention of atelectasis. But it is a common practice for physiotherapists to teach the patients to do expiratory exercise by reversing the incentive spirometer. The simplest way to measure the maximal inspiratory and expiratory pressures is by respiratory pressure meter in cmH2o. OBJECTIVE: To find out the efficacy of incentive spirometer in improving the expiratory muscle strength following abdominal surgery. METHODOLOGY: Quasi-Experimental study. PROCEDURE: 30 subjects were conveniently selected based on inclusion and exclusion criteria and allotted to group A (n=15) and group B (n= 15). Both groups were trained for inspiratory muscle and group A was also trained for expiratory muscle using incentive spirometry. OUTCOME MEASURES: Maximal inspiratory pressure (MIP), Maximal expiratory pressure (MEP). RESULT: This study shows that the mean MIP value have improved from 2nd to 7th postoperative day, but it is not statistically significant (P&gt;0.05). The mean MEP values shows statistically significant (P&lt;0.05) improvement from second to 7th postoperative day in group A when compared to group B. CONCLUSION:This study concludes that there is significant improvement in the expiratory muscle strength along with inspiratory muscle strength by training with the Incentive spirometry in the upside down and upright positions respectively.

Temporary Transvenous Diaphragmatic Neurostimulation in Prolonged Mechanically Ventilated Patients: A Feasibility Trial (RESCUE 1).

Objectives:Prolonged mechanical ventilation promotes diaphragmatic atrophy and weaning difficulty. The study uses a novel device containing a transvenous phrenic nerve stimulating catheter (Lungpacer IntraVenous Electrode Catheter) to stimulate the diaphragm in ventilated patients. We set out to determine the feasibility of temporary transvenous diaphragmatic neurostimulation using this device.Design:Multicenter, prospective open-label single group feasibility study.Setting:ICUs of tertiary care hospitals.Patients:Adults on mechanical ventilation for greater than or equal to 7 days that had failed two weaning trials.Interventions:Stimulation catheter insertion and transvenous diaphragmatic neurostimulation therapy up to tid, along with standard of care.Measurements and Main Results:Primary outcomes were successful insertion and removal of the catheter and safe application of transvenous diaphragmatic neurostimulation. Change in maximal inspiratory pressure and rapid shallow breathing index were also evaluated. Eleven patients met all entry criteria with a mean mechanical ventilation duration of 19.7 days; nine underwent successful catheter insertion. All nine had successful mapping of one or both phrenic nerves, demonstrated diaphragmatic contractions during therapy, and underwent successful catheter removal. Seven of nine met successful weaning criteria. Mean maximal inspiratory pressure increased by 105% in those successfully weaned (mean change 19.7 ± 17.9 cm H2O; p = 0.03), while mean rapid shallow breathing index improved by 44% (mean change –63.5 ± 64.4; p = 0.04).Conclusions:The transvenous diaphragmatic neurostimulation system is a feasible and safe therapy to stimulate the phrenic nerves and induce diaphragmatic contractions. Randomized clinical trials are underway to compare it to standard-of-care therapy for mechanical ventilation weaning.

Agreement between clinical and non-clinical digital manometer for assessing maximal respiratory pressures in healthy subjects.

Measurement of respiratory muscles strength such as maximal inspiratory pressure (MIP) and maximal expiratory pressure (MEP) are used to detect, diagnose and treat respiratory weakness. However, devices used for these measurements are not widely available and are costly. Currently, the use of a digital manometer is recommended. In industry, several inexpensive devices are available, but these have not been validated for clinical use. Our objective was to determine the agreement between maximal respiratory pressures obtained with a clinical digital manometer and that with a non-clinical digital manometer in healthy volunteers. We assessed the height, weight, lung function, MIP, and MEP of healthy volunteers. To compare pressures obtained by each type of digital manometer, a parallel approach configuration was used. The agreement was measured with the Intraclass Coefficient Correlation (ICC) and the Bland-Altman plot. Twenty-seven participants (14 men) were recruited with a median age of 22 (range: 21–23) years. Each participant underwent three measurements to give a total of 81 measurements. The mean MIPs were 90.8 ± 26.4 (SEM 2.9) and 91.1 ± 26.4 (SEM 2.9) cmH2O for the clinical and non-clinical digital manometers, respectively. The mean MEPs were 113.8 ± 40.4 (SEM 4.5) and 114.5 ± 40.5 (SEM 4.5) cmH2O for the clinical and non-clinical digital manometers, respectively. We obtained an ICC of 0.998 (IC 0.997–0.999) for MIP and 0.999 (IC 0.998–0.999) for MEP. There is a high agreement in the values obtained for MIP and MEP between clinical and non-clinical digital manometers in healthy volunteers. Further validation at lower pressures and safety profiling among human subjects is needed.

Effect of inspiratory muscle training on weaning from mechanical ventilation in acute respiratory failure

ObjectiveThis study aimed to evaluate the effect of inspiratory muscle training (IMT) on weaning time and success.Patients and methodsThis is a prospective, randomized clinical study conducted in an ICU. A total of 15 patients were trained by inspiratory muscle exercise twice per day and 15 patients did not go under training (control group). Training was conducted through tuning the ventilator sensitivity based on the patients’ maximal inspiratory pressure (MIP). The experimental group received IMT starting with an initial load of 30% of their MIP measured immediately after changing patients to pressure support mode of mechanical ventilation (MV) and increased up to 40% as tolerated by the patient. Training was conducted for 5 min, two sessions per day. In addition, these patients received usual care of MV patients. Sputum culture assessment for aerobic organisms was done immediately after intubation.ResultsThis is a prospective randomized control study that collected data on 30 patients with acute respiratory failure. Patients were randomly arranged into two groups (control and experimental). The mean MIP before initiation of weaning in both group was 16cm H2O. There is a significant difference in the final mean MIP between the experimental group (23.27 cm H2O) and the control group (17.40 cm H2O). There is also significant shortening in the weaning time in the experimental group and less frequent likelihood of reintubation, which was recorded in two cases of control group.ConclusionThe IMT during MV may assist in early weaning off MV among patients with acute respiratory failure, and also it improves the weaning success rate, with less frequent likelihood of reintubation.

Perioperative Evaluation of Respiratory Muscle Strength after Scoliosis Correction in Patients with Duchenne Muscular Dystrophy

Study DesignRetrospective cohort study.PurposeTo investigate the effect of spinal correction on respiratory muscle strength in patients with Duchenne muscular dystrophy (DMD).Overview of LiteratureSeveral studies have reported that scoliosis correction in patients with DMD does not improve pulmonary function. In these studies, pulmonary function was evaluated using the traditional spirometric values of percent vital capacity (%VC) and percent forced vital capacity (%FVC). However, traditional spirometry may not be suitable for patients with DMD because the results can be influenced by patient fatigue or level of understanding. Therefore, we evaluated respiratory function focusing on respiratory muscle strength using maximal inspiratory pressure (MIP), maximal expiratory pressure (MEP), and sniff nasal inspiratory pressure (SNIP), in addition to %VC and %FVC.MethodsWe retrospectively reviewed 16 patients with DMD who underwent spinal correction surgery between 2006 and 2011 at Kitasato University Hospital. All patients were males, and the mean age was 13.5 years. Respiratory muscle strength was evaluated using MIP, MEP, and SNIP. Measurements were obtained preoperatively and at 1 and 6 months postoperatively, and %VC and %FVC were obtained preoperatively and within 6 months postoperatively.ResultsThe mean preoperative and postoperative %VC values were 54.0% and 51.7%, whereas the mean %FVC values were 53.9% and 53.2%, respectively. The mean MIP, MEP, and SNIP values obtained preoperatively and at 1 and 6 months postoperatively were as follows: MIP, 40.5, 42.7 and 47.2 cm H2O; MEP, 26.0, 28.0, and 29.0 cm H2O; and SNIP, 33.4, 33.0, and 33.0 cm H2O; respectively. The mean MIP and MEP values significantly improved postoperatively. There were no significant differences in SNIP, %VC, or %FVC preand postoperatively.ConclusionsBy focusing on respiratory muscle strength, our results suggest that scoliosis correction in patients with DMD might have a favorable effect on respiratory function.

Exercise capacity, respiratory mechanics and posture in mouth breathers

AbstractChronic and persistent mouth or oral breathing (OB) has been associated with postural changes. Although posture changes in OB causes decreased respiratory muscle strength, reduced chest expansion and impaired pulmonary ventilation with consequences in the exercise capacity, few studies have verified all these assumptions. ObjectiveTo evaluate exercise tolerance, respiratory muscle strength and body posture in oral breathing (OB) compared with nasal breathing (NB) children. Material and methodA cross-sectional contemporary cohort study that included OB and NB children aged 8-11 years old. Children with obesity, asthma, chronic respiratory diseases, neurological and orthopedic disorders, and cardiac conditions were excluded. All participants underwent a postural assessment, maximal inspiratory pressure (MIP), maximal expiratory pressure (MEP), the six-minute walk test (6MWT), and otorhinolaryngologic evaluation. ResultsThere were 107 children (45 OB and 62 NB). There was an association between abnormal cervical posture and breathing pattern: 36 (80.0%) OB and 30 (48.4%) NB presented abnormal head posture (OR=4.27 [95% CI: 1.63-11,42], p<0.001). The mean MIP and MEP were lower in OB (p=0.003 and p=0.004). ConclusionOB children had cervical spine postural changes and decreased respiratory muscle strength compared with NB.

Identification and comparison of the predictors of maximal inspiratory force and handgrip in a healthy elderly population. The proof study

A severe weakness of peripheral muscles occurs in half of the persons aged 80 years or older. The common factors between muscle depletion and reduced respiratory strength have not yet been established. In the subjects of the Proof cohort, we aimed to identify, among body composition, pulmonary function and energy expenditure parameters, the predictors of maximal inspiratory pressure (MIP) as an index of respiratory muscle strength and handgrip (HG) as an index of peripheral muscle strength. In 375 healthy elderly subjects aged 72±1 years, fat mass (FM) and fat free mass (FFM) were assessed by DEXA, the last being also indexed to height (FFMI). Spirometry was performed and daily energy expenditure (DEE) was estimated by a questionnaire. After three years, MIP and HG of the dominant arm were determined and the predicting value of pulmonary function tests, body composition and DEE on these parameters was tested. Mean MIP and HG were 77±26% and 106±19% of the predicted value (%pred) with 90 (24%) and 30 (8%) subjects below standards, respectively. There was a significant but weak correlation between MIP%pred and HG%pred (r=0.175, p<0.001). Logistic regression showed that low MIP was predicted by trunk FFM and FFMI in women, and DEE in men. Low HG was predicted by trunk FM in men only. The predictors of a reduction of MIP in the elderly differ from those of HG, suggesting a differential regulation of respiratory muscle and arm strength.

Respiratory muscle strength of Brazilian adolescents: obtained and predicted values

ResumoObjetivos: Comparar os valores encontrados para as pressões respiratórias máximas de uma amostra de adolescentes brasileiros com os valores preditos por Wilson et al e Domènech-Clar et al. Método: Foram avaliados 156 adolescentes (84 meninos) entre 12 e 17 anos. As pressões respiratórias máximas foram avaliadas por meio de um manovacuômetro digital com os adolescentes sentados e utilizando um clipe nasal. As avaliações das pressões inspiratória e expiratória máximas foram realizadas a partir do volume residual e da capacidade pulmonartotal, respectivamente. A comparação dos valores das pressões respiratórias máximas obtidos no atual estudo com os preditos pelas equações propostas por Wilson et al e Domènech-Clar et al, foi realizada pelo teste t de Student pareado. Para verificar a associação entre estes valores, foi utilizado o teste de correlação de Pearson. Resultados: A média da pressão inspiratória máxima foi de 74,66 ± 22,95 cm H2O e de 103,52 ± 25,67 cm H2O para meninas e meninos, respectivamente. A média da pressão expiratória máxima foi de 86,23 ± 25,92 cm H2O e de 120,08 ± 27,37 cm H2O para meninas e meninos, respectivamente. O svalores obtidos não diferiram e também não se correlacionaram significativamente com os preditos através das equações propostas por Wilson et al., e Domènech-Clar et al. Conclusões: As equações propostas por Wilson et al. e Domènech-Clar et al., não foram capazes de predizer os valores das pressões respiratórias máximas na população estudada, indicando a necessidade de se usar na prática clínica valores de referência advindos de uma população saudável de mesma etnia.

Maximal respiratory pressure reference values for Navajo children ages 6–14

Since anthropometric variables are critical to the creation of pulmonary nomograms for FVC, FEV1, and other volumes and capacities, it is logical that anthropometric variables also influence the values of the maximal respiratory pressures (MRPs). Since nomograms are race-specific, it is important that tribe-specific tables of normal maximal inspiratory pressure (MIP) and maximal expiratory pressure (MEP) be developed. To date normal tables for MRPs do not exist for Navajo children. Therefore the purpose of this study was to derive MRP normative reference values for Navajo children in the age range of 6-14 years. A cross-sectional study was undertaken with a representative sample of 534 healthy children, ages 6-14 years, attending Navajo Nation elementary schools in Arizona. MIP and MEP were measured. Test results from 275 girls and 259 boys met American Thoracic Society quality control standards and showed that MRPs all increased with height. Mean MIP in cm H2 O was 77 for boys and 67 for girls with lower limits of 44 and 40, respectively. Mean MEP in cm H2 O was 75 for boys and 66 for girls with the lower limits of 42 and 38, respectively. Since the data were collected from the population of interest, the resulting MIP and MEP reference equations should be used when testing Navajo children ages 6-14 years.

Valores encontrados e preditos para as pressões respiratórias máximas de crianças brasileiras

OBJECTIVE: to compare the values obtained from the evaluation of maximal inspiratory pressure and maximal expiratory pressure in a sample of Brazilian children with reference values for maximal respiratory pressures proposed by Szeinberg et al., Domenech-Clar et al., and with the predicted equations proposed by Wilson et al. METHODS: observational, cross-sectional study. We assessed 40 female and male children from public schools, aged 7 to 10 years. Personal and anthropometric data were collected in addition to the measurement of maximal respiratory pressures by an MV150 analog manometer (Wika®). RESULTS: mean maximal inspiratory pressure was -61,50 ± 18,14 cmH2O and -70,55 ± 17,94 cmH2O for girls and boys, respectively. Mean maximal expiratory pressure was 77,40 ± 19,00 cmH2O and 77,40 ± 19,04 cmH2O for girls and boys, respectively. CONCLUSION: the values of maximal respiratory pressures obtained by this study in a sample of Brazilian children aged 7 to 10 years did not differ from those proposed by Domenech-Clar et al. However the reference values provided by Szeinberg et al. overestimated the values of maximal respiratory pressures of the children evaluated. The equations proposed by Wilson et al. were successful in predicting the values of maximal respiratory pressures in the population studied.

Kyphoscoliotic Ventilatory Insufficiency: Effects of Long-term Intermittent Positive-Pressure Ventilation

To determine the effects of long-term nocturnal intermittent positive-pressure ventilation (NIPPV) on symptoms, pulmonary function test results, sleep, and respiratory muscle performance in patients with ventilatory insufficiency due to severe kyphoscoliosis. A prospective study in which 16 severe kyphoscoliotic patients were treated with NIPPV delivered by volume-cycled and pressure-cycled ventilators, over a period of 36 months. At baseline, pulmonary function tests, blood gas measurements, polysomnography, and respiratory muscle strength (measured by noninvasive indexes) were obtained. Symptoms and the number of hospitalizations in the previous 6 months also were recorded. Patients then began using a ventilator for > 1 to 2 days, in order to select the type of ventilator and the appropriate interface. Patients returned for evaluation (in outpatient setting) every 6 months for a follow-up period of 3 years. At 6 months, polysomnography was repeated, and by the third year clinical and functional parameters had been reassessed. All symptoms improved significantly with NIPPV therapy, when compared with the baseline values. The mean (+/- SD) PaO(2) and FVC values increased at 36 months compared with baseline values (62.6 +/- 7.1 vs 67.8 +/- 8.8 mm Hg, respectively; and 37.9 +/- 7.2% vs 47.5 +/- 11.9%, respectively; p < 0.05 for both). There were significant improvements in mean maximal inspiratory pressure (55.8 +/- 17.4 to 78.5 +/- 17.5 cm H(2)O), maximal expiratory pressure (53.8 +/- 17.7 to 72.3 +/- 11.0 cm H(2)O), mouth pressure (0.28 +/- 0.08 to 0.22 +/- 0.02 cmH(2)O), and pressure-time index (0.18 +/- 0.05 to 0.11 +/- 0.02; p < 0.05 for all comparisons). There were no significant differences in breathing pattern and ventilatory drive. After 6 months, nocturnal oxyhemoglobin saturation improved, however, there was no significant change in sleep architecture. All patients subjectively perceived a better quality of life after beginning ventilation, which persisted over the course of the study. Long-term NIPPV therapy improves daytime blood gas levels, respiratory muscle performance, and hypoventilation-based symptoms in patients with severe kyphoscoliosis.

Using an evidence-based protocol to guide rehabilitation and weaning of ventilator-dependent cervical spinal cord injury patients.

An evidence-based clinical protocol was developed to improve ventilatory muscle strength and endurance of ventilator-dependent cervical spinal cord injury (SCI) patients. The goal was to help these patients discontinue mechanical ventilation. The protocol, based on findings from other studies in the literature, consisted of pretraining optimization, as well as progressive resistance and endurance training. Following the protocol, mean maximal inspiratory pressure for low tetraplegic patients improved 75 percent, mean maximal expiratory pressure improved 71 percent, mean vital capacity increased 59 percent, mean on-vent endurance time increased 91.6 percent, and mean off-vent breathing time increased 76.7 percent. Both high and low tetraplegic patients achieved gains in inspiratory and expiratory muscle strength, vital capacity, on-vent endurance, and off-vent breathing times. High tetraplegic patients improved their ability to spontaneously ventilate for short periods in case of accidental disconnection from the ventilator, while low tetraplegic patients were able to discontinue mechanical ventilation, which was the desired clinical outcome for this preliminary study.