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ORIGINAL ARTICLE
Year : 2018  |  Volume : 12  |  Issue : 4  |  Page : 399-404

Study of diaphragmatic mobility by chest ultrasound and echocardiographic changes in chronic obstructive pulmonary disease patients on different modes of mechanical ventilation


1 Department of Pulmonary Medicine, Port Saeed University, Cairo, Egypt
2 Department of Cardiology Diseases, Ain Shams University, Cairo, Egypt

Date of Submission16-Jul-2018
Date of Acceptance23-Sep-2018
Date of Web Publication05-Dec-2018

Correspondence Address:
Samir M Fahyim
Building 1, Armed Forces, Maadi Nile, El-Ekhaa City, Cairo, 1234
Egypt
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Source of Support: None, Conflict of Interest: None


DOI: 10.4103/ejb.ejb_52_18

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  Abstract 

Objective This study aimed to assess diaphragmatic mobility by chest ultrasonography and echocardiographic changes in mechanically ventilated chronic obstructive pulmonary disease patients on different modes of mechanical ventilation.
Patients and methods The present study was carried out on 50 mechanically ventilated chronic obstructive pulmonary disease patients. Chest ultrasonography for the assessment of diaphragmatic mobility in addition to echocardiography was performed on different modes of mechanical ventilation in the same session at any time since mechanical ventilation.
Results There was a highly statistically significant relation between diaphragmatic excursion and different modes of mechanical ventilation, where excursion increased significantly, with its peak at pressure-support ventilation (PSV). In terms of diaphragmatic thickness, the thickness of diaphragm decreased significantly at PSV. No significant correlation was detected between echocardiography in Ejection fraction, right ventricular systolic pressure, tricuspid annular plane systolic excursion, and different modes of mechanical ventilation.
Conclusion The best diaphragmatic mobility was on PSV, which improved lung volumes and ventilation, and may accelerate the weaning process. In addition, we concluded that the echocardiographic finding was not affected by different modes of mechanical ventilation.

Keywords: chronic obstructive pulmonary disease, diaphragmatic excursion; dynamic hyperinflation, positive end-expiratory pressure, tricuspid annular plane systolic excursion


How to cite this article:
Saeed AM, Elshahed GS, Osman NM, Gomaa AA, Fahyim SM. Study of diaphragmatic mobility by chest ultrasound and echocardiographic changes in chronic obstructive pulmonary disease patients on different modes of mechanical ventilation. Egypt J Bronchol 2018;12:399-404

How to cite this URL:
Saeed AM, Elshahed GS, Osman NM, Gomaa AA, Fahyim SM. Study of diaphragmatic mobility by chest ultrasound and echocardiographic changes in chronic obstructive pulmonary disease patients on different modes of mechanical ventilation. Egypt J Bronchol [serial online] 2018 [cited 2024 Mar 29];12:399-404. Available from: http://www.ejbronchology.eg.net/text.asp?2018/12/4/399/246880


  Introduction Top


Airway obstruction, pulmonary hyperinflation, and air trapping, as pathological mechanisms of chronic obstructive pulmonary disease (COPD), might be involved in the process of impairment of diaphragmatic dysfunction [1]. Diaphragm dysfunction is one of the leading causes of prolonged mechanical ventilation and weaning failure [2]. Diaphragmatic assessment by chest ultrasound has gained popularity recently in the ICU [3]. Echocardiography is being used routinely in ICUs. It enables direct observation of all cardiac structures [4]. Diaphragmatic displacement measured by ultrasound is one of the most sensitive, specific, and accurate parameters for the assessment of COPD patients for weaning from mechanical ventilation [5].


  Aim of the study Top


This study aimed to assess diaphragmatic mobility by chest ultrasonography and echocardiographic changes in mechanically ventilated COPD patients on different modes of ventilation.


  Patients and methods Top


The present study was carried out on 50 mechanically ventilated COPD patients at Ain Shams University hospitals and Abbassia chest hospital respiratory ICU during the period between August 2016 and Jun 2018. Approved from ethical committee.

Inclusion criteria

All patients who fulfilled the diagnosis criteria of COPD and mechanically ventilated, 40 years of age or older, hemodynamically stable, and fully conscious were included.

Exclusion criteria

Intubation because of surgical or medical problems other than COPD, presence of ascites, colonic distension, lung collapse, fibrosis or pleural effusion, mass, or any mechanical factor in the chest or abdomen interfering with diaphragmatic mobility, patients with diaphragmatic paralysis or diaphragmatic hernia, patients with chest deformities that can affect diaphragmatic mobility such as kyphoscoliosis, patients with primary cardiac diseases (myocardial infarction, cardiomyopathy, pericardial effusion, etc.), unstable hemodynamics, and comatosed not oriented patients, and any patient with known neuromuscular disorder were excluded.

All the patients were subjected to an assessment of full history and a general, local examination, ECG, chest radiography anteroposterior view, routine laboratory investigations such as complete blood count, hepatorenal profile, electrolytes, and assessment of diaphragmatic mobility using baseline chest ultrasound and transthoracic echocardiography at different modes of mechanical ventilation in the same session at any time since mechanical ventilation using a Mindray M7 ultrasound device from Guangzhou Medsinglong Medical Equipment Co., China, Mainland Siemens SONOLINE G60 S system (Diasonic Electro Medical Birati, Kolkata, West Bengal).

Diaphragmatic excursion

Examination of the right diaphragmatic cupola was performed and the B mode was set as the default mode on the device screen. The right side was preferred because of the better sonographic view provided by the liver [6]. Examination was performed using a 3.5°C (bandwidth 2–5 MHz) convex phased array probe (a low-frequency probe with greater depth and enabling assessment of excursion) of ultrasound placed at the anterior axillary line, right subcostal, after the application of ultrasound gel, and was directed medially, cephalic, and dorsally using the liver as an acoustic window for a better view of the diaphragm. Then, a switch was made to the M-mode to observe diaphragmatic movement during inspiration and expiration during quiet breathing, and then the freeze button was pressed on ultrasound device. The difference between the diaphragmatic position during inspiration and expiration was determined and recorded as diaphragmatic excursion (DE).

Diaphragmatic thickness

An M12L linear array probe (bandwidth: 5–13 MHz) was placed at the anterior axillary line of the site of examination by probe of ultrasound put at intercostal space number 7 and intercostal space number 8, yielding an image showing the liver and the lung and a zone of apposition between them using the B mode. Both the pleural lining and the peritoneal lining appeared clearly as two approximately parallel echogenic lines. The space between them resembles diaphragmatic thickness.

Transthoracic echocardiography

A subcostal four-chamber view was preferred as all the patients were emphysematous. Examinations were performed using the available Doppler echocardiogram and a transducer array of 4-2 MHz.

Left ventricular systolic function

Ejection fraction was assessed by M-mode, 2-D techniques in the left parasternal short-axis and long-axis views. Computer software on the echo machine was used to provide a quantitative assessment of left ventricular function. Ejection fraction is normally greater than or equal to 55% and it is mild abnormal when it is from 45 to 54%, moderate (30–44%), severe (<30%) [7].

Right ventricular size

This was assessed by measurement of the right internal mid cavity dimension. It was measured in the apical four-view. The right internal mid cavity dimension is normally less than 34 mm [8].

Tricuspid annular plane systolic excursion

Tricuspid annular plane systolic excursion (TAPSE) was assessed by placing the M-mode cursor on the lateral tricuspid annulus. The maximum plane systolic excursion of the lateral annulus was calculated. TAPSE is normally greater than 1.6 cm [8].

Assessment of the severity of tricusped regurge (TR) was performed by:

Color flow Doppler:
  1. Color flow imaging was performed by visualization of retrograde systolic flow from the right ventricle to the right atrium.
  2. Rapid estimation of TR severity was performed as the larger the jet, the more significant the TR.
  3. TR severity was classified according to the Relative TR Jet Area (Jet Area over Right atrium RA):
    1. Mild TR: jet area (JA)/RA area <20%.
    2. Moderate TR: JA/RA area 20–40%.
    3. Severe TR: JA/RA area >40% [9].


Continuous wave Doppler

Continuous wave Doppler examination was performed in views where parallel alignment with the regurgitant jet was possible and was color Doppler-guided. Qualitative estimation of TR severity was performed on the basis of the shape and density of the signal. The denser the envelope compared with the forward flow, the more severe the TR.

Right ventricular systolic pressure

  1. Right ventricular systolic pressure (RVSP) was estimated on the basis of the modified Bernoulli equation and was considered to be equal to the sPAP.
  2. RVSP=transtricuspid pressure gradient+right atrial pressure.
  3. Transtricuspid gradient is 4v2 (v=peak velocity of tricuspid regurgitation, m/s).
  4. Right atrial pressure was estimated from the end-expiratory diameter of the inferior vena cava. A mild increase in RVSP ranges from 35 to 49 mmHg, moderate RVSP ranges from 50 to 60 mmHg, and severe RVSP greater than 60 mmHg [10].


Statistical methodology

Data were collected, revised, coded, and entered into the statistical package for the social sciences (SPSS; SPSS Inc., Chicago, Illinois, USA) version 23. Quantitative data with a normal distribution were presented as means, SD, and ranges and compared between two groups using an independent t-test, whereas more than two groups were compared using the one-way analysis of variance test. Also, the qualitative data were presented as numbers and percentages and compared between groups using the χ2-test. The confidence interval was set to 95% and the margin of error accepted was set to 5%. Therefore, the P value was considered significant at the level of less than 0.05 [11].


  Results Top


The populations studied were men, ranging in age from 44 to 79 years, with a mean±SD age of 58.68±6.69 years; 64% were manual workers, and had a history of smoking and comorbidities ([Table 1]). There was a highly statistically significant relation between volume control (VC) and pressure control (PC) in DE, where excursion increased in PC; there was also a highly significant relation between them in diaphragmatic thickness, where the thickness increased in VC. There was a highly statistically significant relation between VC and synchronized intermittent mandatory ventilation (SIMV) in DE, where excursion increased in SIMV; there was also a highly significant relation between them in diaphragmatic thickness, where thickness increased in VC. There was a highly significant relation between VC and pressure-support ventilation (PSV) in DE, where excursion increased significantly in PSV; there was also a highly significant relation between them in diaphragmatic thickness, where the thickness increased in VC. There was a statistically significant relation between pressure control ventilation (PCV) and SIMV in DE, where excursion increased in PCV, but there was a nonsignificant relation between them in diaphragmatic thickness. There was a highly statistically significant relation between PCV and PSV in DE, where excursion increased significantly in PSV, but there was a nonsignificant relation between them in diaphragmatic thickness. There was a highly significant relation between SIMV and PSV in DE, where excursion increased in PSV, but there was a nonsignificant relation between them in diaphragmatic thickness ([Table 2]). No significant correlation was detected between echocardiography in ejection fraction, RVSP, TAPSE, and different modes of mechanical ventilation ([Table 3]).
Table 1 Smoking history and co-morbidity among the studied group

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Table 2 Relation between diaphragmatic mobility and diaphragmatic thickness with different modes of mechanical ventilation

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Table 3 Relation between echocardiography and different modes of mechanical ventilation

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  Discussion Top


Management of dynamic hyperinflation at bedside is very difficult in COPD patients because the disease may not have a reversible component [12]. In patients on controlled MV, there is severe diaphragmatic dysfunction and atrophy, and, for this reason, attempts should be made for the patient to early initiate with spontaneous breathings, adjusting the work of breathing [13]. When weaning is difficult or there is refractory hypoxemia that cannot be explained by lung disease alone, echocardiography can yield cardiac morphological and functional analyses that may influence weaning [14]. The present study was carried out on fifty mechanically ventilated COPD patients by assessment of DE and thickness using chest ultrasound at different modes of mechanical ventilation (VC, PC, SIMV, and PS) and assessment of end diastolic volume, ejection fraction, and right-sided systolic pressure using transthoracic echocardiography at different modes of mechanical ventilation (VC, PC, SIMV, and PS). Examinations were performed by the same operator using the same devices of ultrasonography. The majority of patients in this study were men, which may be related to smoking habits. This was in agreement with (GOLD 2015), as in their study, there was a predominance of male COPD patients, and with ElWahsh et al. [15] and also with Helala et al. [16], who found that the majority of COPD patients (97.4%) were men. This study showed that the patients’ age ranged from 44 to 79 years, with a mean age of 58.68±6.69 years. A similar study was carried out by El-Shabrawy et al. [17]; the mean age of COPD patients in their study was 56.97±5.22 years. There was a statistically significant change in diaphragmatic thickness fraction, where the thickness of the diaphragm decreased significantly at PSV. This was in agreement with Umbrello et al. [18], who found that there was a highly statistically significant change in diaphragmatic thickness fraction, where the thickness of the diaphragm decreased with increasing ventilator support. This was also in agreement with the study of Emmanuel et al. [19], which assessed twelve patients during spontaneous breathing; it was found that there was a highly statistically significant change in the diaphragmatic thickness fraction, where the thickness fraction of the diaphragm decreased with increasing ventilator support. In contrast, Shereen and Ali [20] found that in terms of ultrasound diaphragmatic parameters, the diaphragmatic thickness fraction was significantly higher at pressure support of mechanical ventilation and this difference may be because of the difference in the number of days of mechanical ventilation, the age of the patients, and the degree to which the airways were affected in terms of spirometric findings. This study showed a significant change in DE and different modes of mechanical ventilation, where excursion increased significantly, with its peak at PSV. This was in agreement with Shereen and Ali [20], who found that in terms of ultrasound diaphragmatic parameters, DE was significantly higher at pressure support of mechanical ventilation. Our results may explain the results of Esteban et al. [21], who found that spontaneous breathing led to quicker extubation than intermittent mandatory ventilation and PSV. This also was in agreement with the MacIntyre [22] study, which found that PSV improves patient comfort, reduces the patient’s ventilatory work, and provides a more balanced pressure. Also, Hurst et al. [23] found that PSV improves lung volumes and ventilation, and may expedite the weaning process. Brochard et al. [24] found that patients on pressure support had an optimal level of pressure identified as the lowest level maintaining diaphragmatic activity without fatigue. This was in contrast to Umbrello et al. [18], who found that there was no statistically significant change in DE with increasing ventilator support; this difference may have arisen because patients with airflow obstruction were excluded and patients admitted to the ICU after major elective surgery were included in their study. This study showed that there was an insignificant correlation between echocardiography in ejection fraction, RVSP, TAPSE, and different modes of mechanical ventilation.This was in agreement with Luciele et al. [25] and Alexandre et al. [26], who found that no echocardiographic differences were observed between PSV and T‐tube. Our results are in contrast to those of Caille et al. [27], who found that a spontaneous breathing trial induced changes in central hemodynamics and enables identification of patients at high risk of cardiac-related weaning failure when documenting a depressed left ventricular ejection fraction. Also, this was in contrast to Cabello et al. [28], who found that PSV markedly modified the breathing pattern, inspiratory muscle effort, and cardiovascular response compared with the T-piece; this difference may have emerged because a Swan–Ganz catheter was used in the cabello study on different levels of pressure support.


  Conclusion Top


The best diaphragmatic mobility was found on PSV, where improved lung volumes and ventilation were observed, and may have also led to expediting of the weaning process. In addition, we concluded that the echocardiographic finding was not affected by different modes of mechanical ventilation.

Acknowledgements

First of all, the author is very grateful to Allah, the most gracious and merciful for blessing me with all the people who helped to accomplish this piece of work. The author would like to express my profound gratitude to respectful Professor Adel Mohamed Saeed, Professor of Chest Diseases, Ain Shams University, for his continuous support, inspiring guidance, and most valuable suggestions. In addition, the author would like deeply and sincerely to thank Professor Ghada Samir Khalil Elshahed, Professor of Cardiology Diseases, Ain Shams University, for her valuable ideas, meticulous supervision, helpful suggestion and comments. Her contribution in this work was the most fruitful and important. And also the author wish to express gratefulness and appreciation to Dr Nehad Mohammed Osman, Assistant Professor of Chest Diseases Ain Shams University, for generous patience and permanent support. The great cooperation and guidance were essential for this work. Also the author would like to express sincere gratitude to Dr Ashraf Adel Gomaa, Assistant Professor of Chest Diseases, Ain Shams University, for his guidance and endless support through the past years. Last but not least, sincere gratitude to the author’s family for their continuous encouragement and spiritual support.

Financial support and sponsorship

Nil.

Conflicts of interest

There are no conflicts of interest.

 
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    Tables

  [Table 1], [Table 2], [Table 3]


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