Physiology of Body Lateralization on Regional Lung Ventilation Study

Healthy Individuals Clinical Trial

— LATLUNGS  

Official title:

Physiological Effects of Lateral Body Positioning on Regional Ventilation and Ultrasound Diaphragmatic Mobility in Healthy Subjects: an Experimental Study

Clinical Trial Details — Status: Completed

Administrative data

• NCT number: NCT06044896
• Other study ID #: UFPE 5.980.254
• Status: Completed
• Phase: N/A
• Start date: September 22, 2023
• Est. completion date: October 25, 2023

Study information

• Verified date: October 2023
• Source: University of Pernambuco
• Contact: n/a
• Is FDA regulated: No
• Study type: Interventional

Clinical Trial Summary

The goal of this experimental study, with crossover design, is to analyze the effects of body lateralization applied at 30 degrees compared to the supine position on the distribution of ventilation and regional lung aeration in healthy individuals.

The main study questions to be answered are:

• Question 1: What are the immediate effects of 30 degree body lateralization on the distribution of regional ventilation and lung aeration in healthy individuals?

• Question 2: What is the effect of body lateralization on diaphragmatic mobility in the dependent or non-dependent hemithorax?

Participants will be submitted to changes in positioning in bed, considering a randomized sequence of interventions, between supine position and body lateralization at 30 degrees, using the Multicare bed (Linet, Czech Republic). The interventions were repeated twice each with a 30-minute washout in each sequence.

Participants will perform assessment of lung function and respiratory muscle strength with the instruments:

• Manovacuometry

• Spirometry

• Ventilometry

• Respiratory Diagnostic Assistant

The supine and body lateralization positions will be compared, with the primary outcomes being lung aeration and ventilation distribution assessed using Electrical Impedance Tomography. The secondary outcome will be diaphragmatic mobility measured through lung ultrasound.

Groups:

• Supine position

• Body lateralization

Effects

• Lung aeration

• Distribution of ventilation

• Diaphragmatic mobility

Description:

Body positioning is a therapy used in the hospital environment to improve oxygenation. Recent studies recommend lateralization therapy to improve lung function locally by positioning the chest region of interest upwards. However, there are still gaps in the description of the effects of body lateralization on lung aeration and ventilation between non-dependent and gravity-dependent regions and on diaphragmatic mobility.

The objective of this study is to analyze the acute effects of lateralization on the aeration and distribution of lung ventilation, in comparison with the supine position, in healthy subjects. In addition, the effect of body positioning on diaphragm kinetics was evaluated.

This is a crossover study, which will be carried out at the Hospital das Clínicas of the Federal University of Pernambuco (HC-UFPE). The sample will consist of 30 healthy volunteers, aged between 18 and 59 years, of both sexes.

The change of body position will be performed using the Multicare bed (Linet, Praga,Czech Republic).

Lung ventilation and aeration will be evaluated with an Enlight 1800 electrical impedance tomography (EIT) (Timpel Medical, São Paulo, Brazil). The EIT images will be segmented into four regions of interest (ROIs: anterior right, anterior left, posterior right and posterior left. Diaphragm mobility will be quantified by diaphragmatic ultrasound in the supine and lateral positions.

The study was approved by the Research Ethics Committee of the Hospital das Clínicas of the Federal University of Pernambuco (EBSERH), in accordance with the norms of the National Health Council (Resolution 466/12) for research in human beings (opinion number 5,980.254).

Recruitment information / eligibility

• Status: Completed
• Enrollment: 30
• Est. completion date: October 25, 2023
• Est. primary completion date: October 25, 2023
• Accepts healthy volunteers: Accepts Healthy Volunteers
• Gender: All
• Age group: 18 Years to 59 Years

Eligibility

Inclusion Criteria:

• Healthy individuals

• Volunteers aged between 18 and 59 years old (youth/adults)

• Volunteers of both sexes

Exclusion Criteria:

• Individuals with contraindications for the use of manovacuometry, spirometry, ventilometry will be excluded

• Volunteers who did not tolerate the positioning or interventions

• Individuals with Grade III obesity (BMI > 40)

• Participants with below-normal prediction values for manovacuometry and spirometry according to predefined formulas for men and women

• History of flu syndrome in the last seven days.

Related Conditions & MeSH terms

• Healthy Individuals

Intervention

Procedure:
• Supine Positioning
The participant will be guided to the Multicare bed and will be positioned supine with the headboard not tilted. At this point, the participant will already have the EIT electrode belt and head, trunk and lower limb cushions around it, providing stability. After the participant has been correctly positioned, ventilatory monitoring will begin using the EIT. The environment must be fully controlled, that is, with adequate lighting, all collection members in silence, as well as the devices in the place, air-conditioned environment, without exposing the participant to heat or cold. Before starting the collection, the volunteer will be asked to try not to sleep or talk, making it clear that any discomfort can be reported at any time. To keep the volunteer awake, visual and sound stimuli can be performed. Furthermore, if you cough or sigh, the collection will restart. The intervention will last 5 minutes and will be repeated twice, with intervals between body lateralization.
• Body Lateral Positioning
The participant will start from the bench press to the 30-degree lateral position. The cushions placed at the beginning of the collection will provide stability so that the inclination does not compromise the correct positioning of the participant, preventing them from sliding on the bed. Furthermore, it is also a safety measure for the participant. The environment will be controlled throughout the intervention and visual and sound effects will also be performed in lateral positioning. The volunteer will remain in this position for five minutes and shortly after will be placed in the supine position again. To start the protocol for the second and final time, the participant will have a washout time of thirty minutes.

Locations

Country	Name	City	State
Brazil	Hospital das Clínicas da UFPE	Recife
Brazil	Shirley Campos	Recife	Pernambuco

Sponsors (5)

Lead Sponsor	Collaborator
University of Pernambuco	Brazilian National Council for Scientific and Technological Development (CNPq), Coordination for the Improvement of Higher Education Personnel, Pernambuco Research Foundation (FACEPE), Universidade Federal de Pernambuco

Country where clinical trial is conducted

Brazil, 

References & Publications (3)

American Thoracic Society/European Respiratory Society. ATS/ERS Statement on respiratory muscle testing. Am J Respir Crit Care Med. 2002 Aug 15;166(4):518-624. doi: 10.1164/rccm.166.4.518. No abstract available. — View Citation

Laveneziana P, Albuquerque A, Aliverti A, Babb T, Barreiro E, Dres M, Dube BP, Fauroux B, Gea J, Guenette JA, Hudson AL, Kabitz HJ, Laghi F, Langer D, Luo YM, Neder JA, O'Donnell D, Polkey MI, Rabinovich RA, Rossi A, Series F, Similowski T, Spengler CM, Vogiatzis I, Verges S. ERS statement on respiratory muscle testing at rest and during exercise. Eur Respir J. 2019 Jun 13;53(6):1801214. doi: 10.1183/13993003.01214-2018. Print 2019 Jun. — View Citation

Testa A, Soldati G, Giannuzzi R, Berardi S, Portale G, Gentiloni Silveri N. Ultrasound M-mode assessment of diaphragmatic kinetics by anterior transverse scanning in healthy subjects. Ultrasound Med Biol. 2011 Jan;37(1):44-52. doi: 10.1016/j.ultrasmedbio.2010.10.004. — View Citation

Outcome

Type	Measure	Description	Time frame	Safety issue
Other	Respiratory pattern variables	Respiratory pattern variables will be measured by the Respiratory Diagnostic Assistant.; The algorithm of the "Respiratory Diagnostic Assistant" device relates the variables respiratory rate, tidal volume, minute volume, inspiratory flow, expiratory flow, relationship between inspiratory and expiratory times.; Data are given in: Respiratory rate in incursion per minute; Tidal volume (measured in liters); Minute volume (measured in liters); Inspiratory flow (measured in liters); Expiratory flow (measured in liters); Ti/Ttotal, (measured in seconds); I:E, relationship between inspiratory and expiratory times; Volume vs time; Flow vs time.	Not later than 12 months after primary completion date
Other	Frequency of normal and altered breathing patterns	The frequency of normal and altered breathing patterns will be measured by the Respiratory Diagnostic Assistant.; The "Respiratory Diagnosis Assistant" algorithm provides the classification of the diagnosis of breathing patterns as normal or altered, considering the input variables of flow, volume and time.; The normal breathing pattern described in the frequency of cases is when there is no change assessed by the algorithm.; The altered breathing pattern described in the frequency of cases are changes in the breathing pattern variables captured by the device's flow sensor during breathing at rest.; Data are given in: • Absolut and relative frequencies	Not later than 12 months after primary completion date
Other	Lung function measured by Spirometry	Lung function tests are performed by the callibrated spirometer following American Thoracic Society guidelines (2019).; The analysis variables will be: Forced vital capacity (FVC) - given in liters and percentage of predicted value; Forced expiratory volume in 1 second - (FEV1) - given in liters and percentage of predicted value; Relationship between FVC/FEV1 - given in measured value and percentage of predicted value; Furthermore, it allows you to draw up a functional diagnosis: Normal; Obstructive ventilatory disorder (mild, moderate or severe); Restrictive ventilatory disorder (mild, moderate or severe); Mixed ventilatory disorder (with detection of obstructive and restrictive abnormality) Data are given in: Percentages	Not later than 12 months after primary completion date
Other	Lung volumes at rest breathing	Lung volumes at rest breathing will be measured by calibrated ventilometer (Ferraris Mark 8 Wright Respirometer®,. United Kingdom).; Tidal volume (Vt) will be obtained by the ratio between minute volume (MV) and the respiratory rate (RR) observed during one minute of breathing at rest (Vt = MV/RR); Data are given in: Minute volume (MV) measured in liters per minute; Tidal volume (TV), measured in liters.	Not later than 12 months after primary completion date
Other	Lung capacities	Lung capacities will be measured by calibrated ventilometer (Ferraris Mark 8 Wright Respirometer®,. United Kingdom).; Inspiratory capacity (IC) - It's the maximum volume voluntarily inspired from the end of a spontaneous expiration (from the resting expiratory level).; Slow vital capacity (SVC) - measurement taken slowly, starting from a position of full inspiration for complete exhalation.; Data are given in: Inspiratory capacity - measured in liters; Slow vital capacity - measured in liters	Not later than 12 months after primary completion date
Other	Maximum inspiratory pressure (MIP)	Measurement of the maximum static inspiratory pressure that a subject can generate at the mouth measuring inspiratory muscle strength measured by digital manometer (MVD300u, Homed, Brazil); Maximum inspiratory pressure (measured in cmH2O); Maximum predicted inspiratory pressure (predicted %) - MIP predicted =63,27-0,55 (age)+17,96 (sex)+0,58 (weight ); Data are given in: CmH2O; percentage of predicted value	Not later than 12 months after primary completion date
Other	Maximum expiratory pressure (MEP)	Measurement of the maximum static expiratory pressure that a subject can generate at the mouth measuring expiratory muscle strength measured by digital manometer (MVD300u, Homed, Brazil); Maximum expiratory pressure (cmH2O); Maximum predicted expiratory pressure (predicted %); MEP =-61,41+2,29 (age)-0,03 age2)+33,72 (sex)+1,40 (waist); Data are given in: CmH2O; percentage of predicted value	Not later than 12 months after primary completion date
Primary	Change in end-expiratory lung impedance (Delta EELZ)	Lung aeration will be assessed using Electrical Impedance Tomography (EIT). Regional EELZ will be calculated and analyzed concerning intervention times.; The change in aeration distribution or change in end-expiratory lung impedance (Delta EELZ) will be determined by comparing pre- and post-intervention EELZ for lung quadrants and dependent/non-dependent regions in each intervention.; End-expiratory lung impedance (EELZ) represents the sum of the end-expiratory impedance values of the pixels in a given region of interest. Regions of interest include: right anterior, left anterior, right posterior and left posterior, and functionally, dependent or non-dependent lung.; Continuous EIT monitoring will occur, and outcomes will be assessed before and after each intervention, each lasting five minutes.; Data are given in: arbitrary units (a.u.); mililiters; percentages	Not later than 12 months after primary completion date
Primary	Change in distribution of lung ventilation (Delta Z)	The distribution of lung ventilation will also be assessed using electrical impedance tomography.; The impedance variation (Delta Z) represents the sum of the impedance values of the pixels in a given region of interest. Regions of interest include: right anterior, left anterior, right posterior and left posterior, and functionally, dependent or non-dependent lung.; The change in distribution of lung ventilation will be obtained by the difference between the Delta Z before and after each intervention, comparing the measurements of the lung quadrants and in the dependent and non-dependent lung regions for each intervention.; Continuous EIT monitoring will occur, and outcomes will be assessed before and after each intervention, each lasting five minutes.; Data are given in: arbitrary units (a.u.); mililiters; percentages	Not later than 12 months after primary completion date
Secondary	Difference in diaphragmatic mobility measured by ultrasound between the supine and body lateralization positions.	Diaphragmatic mobility will be evaluated in the supine position and in the body lateralization position during the intervention using ultrasound, according to protocol from TESTA, A. et al 2011.; Measurements will be carried out with the patient breathing spontaneously in supine and body lateralization position at 30º.; Data are given in: • Millimeters.	Not later than 12 months after primary completion date