Diaphragm Thickening Fraction

Brugge , March. 19th 2016

Thoracic Ultrasound To investigate the pleura, lungs and diaphragm Aymeric LE NEINDRE, PT, MSc Forcilles Hospital, Férolles-Attilly & St. Joseph Hospital, Paris, France

Basics of ultrasound

Equipment

Image processing and displaying

Ultrasound emission and reception

Ultrasound processing

Probes

Linear

Convex

High frequency

Low frequency

Acoustic Impedance Medium Air Water Blood Kidney & Spleen Liver Muscle Bone

Impedance (10 /Kg/m /s 0,0004 1,48 1,68 1,62 1,63 à 1,67 1,67 à 1,76 3,65 à 7

Air: reflects all of the US Bone: absorbs all of the US

6

2

Useful terms • Hyperechoic – Reflection – Brightness

• Anechoic – No reflection – Black color

• Echoic to hypoechoic – Grayscale

Ultrasound Modes • B-Mode – Brightness, Real-time – Two-dimensionnal View

• M-Mode – Motion – Visualization of structures motion like a function of time

• Doppler Color Mode – Visualization of fluid movement

Basics of Thoracic Ultrasound

7

1 principles

• A simple equipment is perfectly adapted • In the thorax, gas and fluid are mingled by pathologic processes – High acoustic impedance difference generating

• • • • •

All signs arise from pleural line Static signs are mainly artifactual Signs arising from pleural line are foremost dynamic Almost all acute thoracic disorders reach pleural line The lung is the most voluminous organ. Examination areas can be defined

[1] Lichtenstein et al., Lung ultrasound in the critically ill, Annals of intensive care, 2014

Thoracic

2 areas 6 hemithoracic areas Anterior Lateral Posterior Superior and inferior subdivisions

PSL: Parasternal lineL - AAL: Anterior Axillary Line - PAL: Posterior Axillary Line [2] Volpicelli et al., International evidence-based recommendations for point-of-care lung ultrasound, Intensive Care Med, 2012

Longitudinal view

Probe into an IC space Cranio-caudal axis Capture image sur http://www.sonosite.com/fr/education /learning-center

Normal Lung Ultrasound

3 signs = artifacts A Lines

Bat sign

Pleural sliding

Bat sign and A-lines (B-mode)

A-line

A-line

Artifacts formation Probe Subcutaneous Tissues Sup Rib

Intercostal Muscles

Lung (Air)

Inf Rib

Pleura

Artefact 1: rib shadow

Absorption

Hyperechoic line

Côte Rib shadow

Artefact 2: reflection Probe

Reflection

Pleura

Lung (Air) US are stopped to the pleura

Artefact 3: reverberation Probe Parietal Pleura

Pleura Visceral Pleura

A-line

A-line

Bat sign and A-lines (B-mode)

A-line

A-line

Pleural sliding: seashore sign

M-Mode

B-Mode

Tissues above pleural line are motionless and generate horizontal lines (sea). Below the pleural line, structures are in motion and generate a sandy pattern.

Normal Lung Ultrasound

Pathologic signs

B-lines (B-mode) (1) • Comet-tail artifacts • Arise from pleural line without fading out and erasing A-lines • B-lines are generated by presence of air and water mixed – Mismatching of acoustic impedance

• It refers to interstitial syndrome

B-lines (B-mode) (2)

Pleural line Rib Shadow

B-lines (B-mode) (3)

B-lines & Interstitial syndrome Bouhemad et al., Ultrasound assessment of antibiotic-induced pulmonary reaeration in ventilator-associated pneumonia, Crit Care Med, 2010

Le Neindre A., Lebret M., Wormser J. L'échographie pulmonaire : principes de base et perspectives d'utilisation en kinésithérapie respiratoire. Kinésithér Scient. 2015

Tissue-like sign (B-mode)

Tissue-like pattern arising from pleural line of a lobar consolidation

Shred sign (B-mode)

Deep boundary (arrow), with shredded appearance, of a partial lobar consolidation

Quad Sign (B-mode) Pp E Pv

C

F

It highlights presence of pleural effusion

Pleural effusion and consolidation

Diaphragm assessment

Diaphragm sonography • Simple, noninvasive and easily accessible tool to assess the diaphragm • Ultrasound allows to assess… – Mobility (excursion) – Thickness (tdi) – Contractility (Diaphragm Thickening Fraction (DTF))

… of the diaphragm

Diaphragmatic excursion (1)

Method 1 Boussuges et al., Diaphragmatic motion studied by m-mode ultrasonography: Methods, reproducibility, and normal values, Chest, 2009



Method 2 Lerolle et al., ULtrasonographic diagnostic criterion for severe diaphragmatic dysfunction after cardiac surgery, Chest, 2009


Diaphragm Thickening Fraction (1)

Matamis et al., Sonographic evaluation of the diaphragm in critically ill patients. Technique and clinical applications, Intensive Care Med, 2013 Vivier et al., Diaphragm ultrasonography to estimate the work of breathing during noninvasive ventilation, Intensive Care Med, 2012

Diaphragm Thickening fraction (2)



Reference values • Normal diaphragm function – DTF = 28-96% (Summerhill, Chest, 2008) – Excursion (deep breathing) = 7 ± 1,1 cm (men), 5,7 ± 1 cm (women) (Boussuge, Chest, 2009)

• Diaphragm dysfunction – DTF < 20 % (Summerhill, Chest, 2008) – Excursion < 25 mm (Lerolle, Chest, 2009)

Physiotherapist’s clinical decision-making process

Le Neindre A, Mongodi S, Philippart F, Bouhemad B. Thoracic ultrasound: Potential new tool for physiotherapists in respiratory management. A narrative review. J Crit Care. 2016;31(1):101–9.

CPT Outcome measures (1) • Need to use Tools which are – Accurate – Valid – Reliable

• In order to – – – – –

Assess deficiencies Choice most suited techniques Assess CPT effectiveness Monitor patient evolution Use good outcomes for clinical research

CPT Outcome measures (2)

Lichtenstein et al., Comparative Diagnostic Performances of Auscultation, Chest Radiography, and Lung Ultrasonography in Acute Respiratory Distress Syndrome, Anesthesiology, 2004

Physiotherapist’s clinical decision-making process Example of a case with abolished vesicular sound, dullness and decreased thoracic mobility at the lung bases

Pleural effusion ? (1) Pleural effusion

No

Yes

Re-adress to medical staff

If no chest drain required

Assess the lung aeration level Assess the diaphragm function

Help to decrease the WOB (refer to clinical examination)

Pleural effusion ? (2)

Pleural effusion ? (3)

Pleural effusion (4)

Lung aeration level assessment Is the lung recruitable?

Yes

Assess the diaphragm function

Manual or ventilator hyperinflation Positioning

Atelectasis

No

NIV/CP AP

Pneumonia

Ex.: atelectasis

NIV + laterocubitus

Post-treatment

Diaphragm function Diaphragm dysfunction

Yes Recovery monitoring

Inspiratory Muscle Training?

No Re-adress to medical staff Assess the lung aeration level

Ventilated COPD excursion

Ventilated ALS excursion

Conclusion (1) • Lung Ultrasound is an assessment and monitoring tool: – – – –

Valid, accurate and reliable Easy to use Inexpensive Ionization free

• Easy to access in all ICU departments • Need to be developped in other departments (ex: Physiotherapy) and in ambulatory care

Conclusion (2)

Conclusion (3)

Thank you !

Correspondence to: Aymeric LE NEINDRE, [email protected]