Air trapping: The major factor limiting diaphragm mobility in chronic obstructive pulmonary disease patients

The Manual Diaphragm Release Technique improves diaphragmatic mobility, inspiratory capacity and exercise capacity in people with chronic obstructive pulmonary disease: a randomised trial

QUESTIONS

In people with chronic obstructive pulmonary disease, does the Manual Diaphragm Release Technique improve diaphragmatic mobility after a single treatment, or cumulatively? Does the technique also improve exercise capacity, maximal respiratory pressures, and kinematics of the chest wall and abdomen?

DESIGN

Randomised, controlled trial with concealed allocation, intention-to-treat analysis, and blinding of participants and assessors.

PARTICIPANTS

Twenty adults aged over 60 years with clinically stable chronic obstructive pulmonary disease.

INTERVENTION

The experimental group received six treatments with the Manual Diaphragm Release Technique on non-consecutive days within a 2-week period. The control group received sham treatments following the same regimen.

OUTCOME MEASURES

The primary outcome was diaphragmatic mobility, which was analysed using ultrasonography. The secondary outcomes were: the 6-minute walk test; maximal respiratory pressures; and abdominal and chest wall kinematics measured by optoelectronic plethysmography. Outcomes were measured before and after the first and sixth treatments.

RESULTS

The Manual Diaphragm Release Technique significantly improved diaphragmatic mobility over the course of treatments, with a between-group difference in cumulative improvement of 18mm (95% CI 8 to 28). The technique also significantly improved the 6-minute walk distance over the treatment course, with a between-group difference in improvement of 22 m (95% CI 11 to 32). Maximal expiratory pressure and sniff nasal inspiratory pressure both showed significant acute benefits from the technique during the first and sixth treatments, but no cumulative benefit. Inspiratory capacity estimated by optoelectronic plethysmography showed significant cumulative benefit of 330ml (95% CI 100 to 560). The effects on other outcomes were non-significant or small.

CONCLUSION

The Manual Diaphragm Release Technique improves diaphragmatic mobility, exercise capacity and inspiratory capacity in people with chronic obstructive pulmonary disease. This technique could be considered in the management of people with chronic obstructive pulmonary disease.

TRIAL REGISTRATION

NCT02212184.

Anxiety and depression are related to dyspnea and clinical control but not with thoracoabdominal mechanics in patients with COPD

OBJECTIVE

To investigate the relationship between the presence of symptoms of anxiety or depression with breathing pattern and thoracoabdominal mechanics at rest and during exercise in COPD.

METHODS

Cross-sectional study enrolled 54 patients with COPD ranked according to Hospital Anxiety and Depression Scale (HAD) score and compared to dyspnea, clinical control, hypercapnia, breathing pattern and thoracoabdominal mechanics at rest and during exercise.

RESULTS

Seventeen patients with COPD had no symptoms, 12 had anxiety symptoms, 13 had depressive symptoms and 12 had both symptoms. COPD with depressive symptoms presented greater degree of dyspnea (p<0.01). Poor clinical control was observed in COPD with anxious and/or depressive symptoms (p<0.05). Breathing pattern and thoracoabdominal mechanics were similar among all groups at rest and during exercise.

CONCLUSIONS

COPD with symptoms of depression report more dyspnea. Anxiety and depression are associated with poor clinical control without impact on breathing pattern and thoracoabdominal mechanics in COPD.

Ultrasound in obstructive lung diseases: the effect of airway obstruction on diaphragm kinetics. A short pictorial essay

The ultrasound study of the chest is showing a continuous development. This technique could be helpful in managing several chest diseases, but it is limited to the acoustic windows provided by intercostal spaces and by the inability to study healthy lung parenchyma and all intra-parenchymal diseases such as chronic obstructive lung disease (COPD), because the interaction between ventilated lung and ultrasound generates only artifacts. Currently, there are few applications of ultrasound that are useful in COPD, with recent studies providing some innovation potentially useful in clinical practice. The similarity of the trend between the time/volume curve of spirometry and the M-mode representation of diaphragm during forced breath allowed to identify the M-mode Index of Obstruction (MIO), an index obtained from the ratio between forced diaphragmatic excursion in the first second (FEDE1, cm) and the maximal expiratory diaphragmatic excursion (EDEMax, cm). MIO has shown a linear correlation with the ratio between forced expiratory volume in the first second (FEV1) and vital capacity (VC), used in spirometry to identify airways obstruction. The value of MIO seems to be lower in patients affected by airways obstruction as showed by a recent study. The technique is easy to learn and fast to perform and the analysis could be provided with any ultrasound machine equipped with M-mode. In conclusion, these findings, if confirmed by other studies, could suggest a new add-on screening tool for obstructive lung diseases, in particular COPD, that could be performed during a routine abdominal ultrasound exam.

Respiratory pattern of diaphragmatic breathing and pilates breathing in COPD subjects

BACKGROUND:

Diaphragmatic breathing (DB) is widely used in pulmonary rehabilitation (PR) of patients with chronic obstructive pulmonary disease (COPD), however it has been little studied in the scientific literature. The Pilates breathing (PB) method has also been used in the rehabilitation area and has been little studied in the scientific literature and in COPD.

OBJECTIVES:

To compare ventilatory parameters during DB and PB in COPD patients and healthy adults.

METHOD:

Fifteen COPD patients (COPD group) and fifteen healthy patients (healthy group) performed three types of respiration: natural breathing (NB), DB, and PB, with the respiratory pattern being analyzed by respiratory inductive plethysmography. The parameters of time, volume, and thoracoabdominal coordination were evaluated. After the Shapiro-Wilk normality test, ANOVA was applied followed by Tukey's test (intragroup analysis) and Student's t-test (intergroup analysis; p<0.05).

RESULTS:

DB promoted increase in respiratory volumes, times, and SpO₂ as well as decrease in respiratory rate in both groups. PB increased respiratory volumes in healthy group, with no additional benefits of respiratory pattern in the COPD group. With respect to thoracoabdominal coordination, both groups presented higher asynchrony during DB, with a greater increase in the healthy group.

CONCLUSIONS:

DB showed positive effects such as increase in lung volumes, respiratory motion, and SpO₂ and reduction in respiratory rate. Although there were no changes in volume and time measurements during PB in COPD, this breathing pattern increased volumes in the healthy subjects and increased oxygenation in both groups. In this context, the acute benefits of DB are emphasized as a supporting treatment in respiratory rehabilitation programs.

Ultrasound analysis of diaphragm kinetics and the diagnosis of airway obstruction: the role of the M-mode index of obstruction

Diaphragm motion in forced expiration can be analyzed using M-mode ultrasound in an anterior subcostal approach. Maximum expiratory diaphragmatic excursion (EDEMax) and forced expiratory diaphragmatic excursion in the first second (FEDE1) are considered the physiopathological analogues of vital capacity (VC) and forced expiratory volume in the first second (FEV1). As the FEV1/VC % ratio is used as a marker of obstruction, our aim was to determine if the ratio FEDE1/EDEMax (M-mode index of obstruction [MIO]) differs between healthy subjects and patients with airway obstruction. One hundred twenty-four outpatients were examined by diaphragm ultrasound after spirometry. The MIO, expressed as the mean ± standard deviation (range), was 87.08 ± 6.64 (72.84-100) in the healthy group (N = 61) and 67.09 ± 12.49 (33.33-91.30) in the group with obstructed airways (N = 63). The difference between the two groups was significant (p < 0.0001), and MIO was significantly correlated with FEV1/VC (p < 0.0001). A MIO <77 was identified as a possibile cutoff for suspecting an obstructive spirometric pattern with a 95.5% positive predictive value. The MIO can be interpreted as a speed index of diaphragmatic relaxation that seems to be slower in obstructed patients and could be used to screen for obstructed airway diseases.

Diaphragmatic motion studied by M-mode ultrasonography in combined pulmonary fibrosis and emphysema

BACKGROUND

The coexistence of emphysema and pulmonary fibrosis is known as combined pulmonary fibrosis and emphysema (CPFE). The aim of this study was to compare diaphragmatic motion measured by M-mode ultrasonography of patients with CPFE, idiopathic pulmonary fibrosis (IPF), and chronic obstructive pulmonary disease (COPD).

METHODS

Pulmonary function, high-resolution computed tomography (HRCT), and diaphragmatic motion were examined in patients with CPFE (n = 25), IPF (n = 18), and COPD (n = 60), and in healthy controls (n = 21). Diaphragmatic motions were measured on M-mode ultrasonographic images during quiet breathing and deep breathing.

RESULTS

There were no significant differences in right or left diaphragmatic motion during quiet breathing among the four groups, whereas differences were significant in right and left motion during deep breathing. Diaphragmatic motion in CPFE patients was the lowest among the four groups. COPD patients, especially those with severe COPD, showed significantly lower diaphragmatic motion than IPF patients or healthy controls. There were no differences in diaphragmatic motion between IPF patients and healthy controls. Right diaphragmatic motions during deep breathing were negatively correlated with emphysema scores (r = -0.606, p < 0.001), but were not correlated with fibrosis scores on HRCT.

CONCLUSIONS

Diaphragmatic weakness was found in CPFE patients. Emphysema but not fibrosis may be one cause of limited diaphragmatic motion in patients with CPFE. M-mode ultrasonographic evaluation of diaphragmatic motion during deep breathing may be a useful tool in diagnosing CPFE and in discriminating CPFE patients from IPF or COPD patients.

Ultrasonographic assessment of the diaphragm in chronic obstructive pulmonary disease patients: relationships with pulmonary function and the influence of body composition - a pilot study

BACKGROUND

Skeletal muscle weakness with loss of fat-free mass (FFM) is one of the main systemic effects of chronic obstructive pulmonary disease (COPD). The diaphragm is also involved, leading to disadvantageous conditions and poor contractile capacities.

OBJECTIVES

We measured the thickness of the diaphragm (TD) by ultrasonography to evaluate the relationships between echographic measurements, parameters of respiratory function and body composition data.

METHODS

Thirty-two patients (23 males) underwent (1) pulmonary function tests, (2) echographic assessment of TD in the zone of apposition at various lung volumes, i.e. TD at residual volume (TDRV), TD at functional residual capacity (TDFRC) and TD at total lung capacity (TDTLC), and (3) bioelectrical body impedance analysis. The BMI and the BODE (BMI-Obstruction-Dyspnea-Exercise) index values were reported.

RESULTS

TDRV, TDFRC and TDTLC measured 3.3, 3.6 and 6 mm, respectively, with good intraobserver reproducibility (0.97, 0.97 and 0.96, respectively). All the TDs were found to be related to FFM, with the relationship being greater for TDFRC (r(2) = 0.39 and p = 0.0002). With regard to lung volumes, inspiratory capacity (IC) was found to be closely related to TDTLC (r(2) = 0.42 and p = 0.0001). The difference between TDTLC and TDRV, as a thickening value (TDTLCRV), was closely related to FVC (r(2) = 0.34 and p = 0.0004) and to air-trapping indices (RV/TLC, FRC/TLC and IC/TLC): the degree of lung hyperinflation was greater and the TDTLCRV was less. Finally, we found a progressive reduction of both thicknesses and thickenings as the severity of IC/TLC increased, with a significant p value for the trend in both analyses (p = 0.02).

CONCLUSIONS

Ultrasonographic assessment of the diaphragm could be a useful tool for studying disease progression in COPD patients, in terms of lung hyperinflation and the loss of FFM. © 2014 S. Karger AG, Basel.

Diaphragmatic breathing training program improves abdominal motion during natural breathing in patients with chronic obstructive pulmonary disease: a randomized controlled trial

OBJECTIVE

To investigate the effects of a diaphragmatic breathing training program (DBTP) on thoracoabdominal motion and functional capacity in patients with chronic obstructive pulmonary disease.

DESIGN

A prospective, randomized controlled trial.

SETTING

Academic medical center.

PARTICIPANTS

Subjects (N=30; forced expiratory volume in 1s, 42%±13% predicted) were randomly allocated to either a training group (TG) or a control group (CG).

INTERVENTIONS

Subjects in the TG completed a 4-week supervised DBTP (3 individualized weekly sessions), while those in the CG received their usual care.

MAIN OUTCOME MEASURES

Effectiveness was assessed by amplitude of the rib cage to abdominal motion ratio (RC/ABD ratio) (primary outcome) and diaphragmatic mobility (secondary outcome). The RC/ABD ratio was measured using respiratory inductive plethysmography during voluntary diaphragmatic breathing and natural breathing. Diaphragmatic mobility was measured by ultrasonography. A 6-minute walk test and health-related quality of life were also evaluated.

RESULTS

Immediately after the 4-week DBTP, the TG showed a greater abdominal motion during natural breathing quantified by a reduction in the RC/ABD ratio when compared with the CG (F=8.66; P<.001). Abdominal motion during voluntary diaphragmatic breathing after the intervention was also greater in the TG than in the CG (F=4.11; P<.05). The TG showed greater diaphragmatic mobility after the 4-week DBTP than did the CG (F=15.08; P<.001). An improvement in the 6-minute walk test and in health-related quality of life was also observed in the TG.

CONCLUSIONS

DBTP for patients with chronic obstructive pulmonary disease induced increased diaphragm participation during natural breathing, resulting in an improvement in functional capacity.

Detection of air trapping in chronic obstructive pulmonary disease by low frequency ultrasound

BACKGROUND

Spirometry is regarded as the gold standard for the diagnosis of COPD, yet the condition is widely underdiagnosed. Therefore, additional screening methods that are easy to perform and to interpret are needed. Recently, we demonstrated that low frequency ultrasound (LFU) may be helpful for monitoring lung diseases. The objective of this study was to evaluate whether LFU can be used to detect air trapping in COPD. In addition, we evaluated the ability of LFU to detect the effects of short-acting bronchodilator medication.

METHODS

Seventeen patients with COPD and 9 healthy subjects were examined by body plethysmography and LFU. Ultrasound frequencies ranging from 1 to 40 kHz were transmitted to the sternum and received at the back during inspiration and expiration. The high pass frequency was determined from the inspiratory and the expiratory signals and their difference termed ΔF. Measurements were repeated after inhalation of salbutamol.

RESULTS

We found significant differences in ΔF between COPD subjects and healthy subjects. These differences were already significant at GOLD stage 1 and increased with the severity of COPD. Sensitivity for detection of GOLD stage 1 was 83% and for GOLD stages worse than 1 it was 91%. Bronchodilator effects could not be detected reliably.

CONCLUSIONS

We conclude that low frequency ultrasound is cost-effective, easy to perform and suitable for detecting air trapping. It might be useful in screening for COPD.

TRIAL REGISTRATION

ClinicalTrials.gov: NCT01080924.

Weakness of expiratory muscles and pulmonary complications in malnourished patients undergoing upper abdominal surgery

BACKGROUND AND OBJECTIVE

Malnutrition is prevalent in hospitalized patients and causes systemic damage including effects on the respiratory and immune systems, as well as predisposing to infection and increasing postoperative complications and mortality. This study aimed to assess the impact of malnutrition on the rate of postoperative pulmonary complications, respiratory muscle strength and chest wall expansion in patients undergoing elective upper abdominal surgery.

METHODS

Seventy-five consecutive candidates for upper abdominal surgery (39 in the malnourished group (MNG) and 36 in the control group (CG)) were enrolled in this prospective controlled cohort study. All patients were evaluated for nutritional status, respiratory muscle strength, chest wall expansion and lung function before surgery. Postoperative pulmonary complications (pneumonia, tracheobronchitis, atelectasis and acute respiratory failure) before discharge from hospital were also evaluated.

RESULTS

The MNG showed expiratory muscle weakness (MNG 65 ± 24 vs CG 82 ± 22 cm H(2) O; P < 0.001) and decreased chest wall expansion (P < 0.001), whereas inspiratory muscle strength and lung function were preserved (P > 0.05). The MNG also had a higher incidence of postoperative pulmonary complications compared with the CG (31% and 11%, respectively; P = 0.05). In addition, expiratory muscle weakness was correlated with BMI in the MNG (r = 0.43; P < 0.01). The association between malnutrition and expiratory muscle weakness increased the likelihood of postoperative pulmonary complications after upper abdominal surgery (P = 0.02).

CONCLUSIONS

These results show that malnutrition is associated with weakness of the expiratory muscles, decreased chest wall expansion and increased incidence of pulmonary complications in patients undergoing elective upper abdominal surgery.

Influence of diaphragmatic mobility on hypercapnia in patients with chronic obstructive pulmonary disease

A reduction in diaphragm mobility has been identified in patients with chronic obstructive pulmonary disease (COPD) and has been associated with a decline in pulmonary function parameters. However, little information exists regarding the potential role of diaphragm mobility on hypercapnia in COPD. A new method of assessing the mobility of the diaphragm, using ultrasound, has recently been validated. The purpose of the present study was to investigate the relationship between diaphragm mobility and pulmonary function parameters, as well as that between arterial blood gas values and diaphragm mobility, in COPD patients. Thirty seven COPD patients were recruited for pulmonary function test, arterial blood gas analysis and diaphragm mobility using ultrasound to measure the craniocaudal displacement of the left branch of the portal vein. There were significant negative correlations between diaphragmatic mobility and P(a)CO(2) (r = -0.373, P = 0.030). Diaphragmatic mobility correlated with airway obstruction (FEV(1), r = 0.415, P = 0.011) and with ventilatory capacity (FVC, r = 0.302, P = 0.029; MVV, r = 0.481, P = 0.003). Diaphragmatic mobility also correlated significantly with pulmonary hyperinflation. No relationship was observed between diaphragm mobility and P(a)O(2) (r = -0.028, P = 0.873). These findings support a possibility that the reduction in diaphragm mobility relates to hypercapnia in COPD patients.

Mobilidade diafragmática durante espirometria de incentivo orientada a fluxo e a volume em indivíduos sadios

OBJETIVO: Comparar a mobilidade diafragmática de indivíduos sadios durante a espirometria de incentivo orientada a volume, durante a espirometria de incentivo orientada a fluxo e durante exercícios diafragmáticos. Comparar a mobilidade diafragmática entre homens e mulheres durante esses três tipos de exercícios respiratórios. MÉTODOS: Foram avaliadas a função pulmonar e a mobilidade diafragmática de 17 voluntários sadios adultos (9 mulheres e 8 homens). A avaliação da mobilidade do diafragma foi realizada durante a execução de exercícios diafragmáticos e durante o uso dos dois tipos de espirômetros de incentivo, por meio de um método ultrassonográfico. RESULTADOS: A mobilidade diafragmática avaliada durante a utilização do espirômetro orientado a volume foi significativamente maior que aquela durante o uso do espirômetro orientado a fluxo (70,16 ± 12,83 mm vs. 63,66 ± 10,82 mm; p = 0,02). Os exercícios diafragmáticos promoveram maior mobilidade diafragmática do que o uso do espirômetro orientado a fluxo (69,62 ± 11,83 mm vs. 63,66 ± 10,82 mm; p = 0,02). Durante os três tipos de exercícios respiratórios, a relação mobilidade/CVF foi significativamente maior nas mulheres do que nos homens. CONCLUSÕES: A espirometria de incentivo orientada a volume e o exercício diafragmático promoveram maior mobilidade diafragmática do que a espirometria de incentivo orientada a fluxo. As mulheres apresentaram um melhor desempenho nos três tipos de exercícios respiratórios avaliados do que os homens.

Diaphragmatic dysfunction and mortality in patients with COPD

OBJECTIVE

To determine whether COPD patients with diaphragmatic dysfunction present higher risk of mortality than do those without such dysfunction.

METHODS

We evaluated pulmonary function, diaphragm mobility and quality of life, as well as determining the Body mass index, airway Obstruction, Dyspnea, and Exercise capacity (BODE) index, in 42 COPD patients. The patients were allocated to two groups according to the degree to which diaphragm mobility was impaired: low mobility (LM; mobility < 33.99 mm); and high mobility (HM; mobility > 34.00 mm). The BODE index and the quality of life were quantified in both groups. All patients were followed up prospectively for up to 48 months in order to determine the number of deaths resulting from respiratory complications due to COPD.

RESULTS

Of the 42 patients evaluated, 20 were allocated to the LM group, and 22 were allocated to the HM group. There were no significant differences between the groups regarding age, lung hyperinflation or quality of life. However, BODE index values were higher in the LM group than in the HM group (p = 0.01). During the 48-month follow-up period, there were four deaths within the population studied, and all of those deaths occurred in the LM group (15.79%; p = 0.02).

CONCLUSIONS

These findings suggest that COPD patients with diaphragmatic dysfunction, characterized by low diaphragm mobility, have a higher risk of death than do those without such dysfunction.