LUNG ULTRASOUND FOR PULMONARY OEDEMA

Kylie Baker

Ipswich Hospital, Qld

Ultrasound is not for everyone, but everyone can understand the terminology, recognise a good scan from a poor one, and understand its error rate.

DISCLAIMER

This talk:-

Background Rationale- screening tool vs definitive. Acquisition Interpretation Tweaks

Background

The Comet-tail Artifact

An Ultrasound Sign of Alveolar-Interstitial SyndromeDANIEL LICHTENSTEIN, GILBERT MEZIERE, PHILIPPE BIDERMAN, AGNES GEPNER, and OLIVIER BARRE

Service de Reanimation Medicale and Service de Radiologie, Hopital Ambroise-Pare, Boulogne (Paris), and Service de Reanimation Polyvalente, Centre Hospitalier General, Saint-Cloud (Paris), France

AM J RESPIR CRIT CARE MED 1997;156:1640–1646.

International evidence-based recommendations for point-of-care lung ultrasound

Intensive Care MedDOI 10.1007/s00134-012-2513-4 Giovanni Volpicelli Mahmoud Elbarbary Michael BlaivasDaniel A. Lichtenstein Gebhard Mathis Andrew W. Kirkpatrick Lawrence Melniker Luna Gargani

Vicki E. Noble Gabriele Via Anthony Dean James W. Tsung Gino Soldati Roberto Copetti Belaid Bouhemad Angelika Reissig Eustachio Agricola Jean-Jacques Rouby Charlotte Arbelot Andrew Liteplo Ashot Sargsyan Fernando Silva Richard Hoppmann Raoul Breitkreutz Armin Seibel

Luca NeriEnrico StortiTomislav PetrovicInternational Liaison Committee on Lung Ultrasound (ILC-LUS) for the InternationalConsensus Conference on Lung Ultrasound (ICC-LUS)

CONFERENCE REPORTS AND EXPERT PANEL

International evidence-based recommendations for point-of-care lung ultrasound Published online March 2012

“This pattern was present all over the lung surface in 86 of 92 patients with diffuse alveolar-interstitial syndrome (sensitivity of 93.4%). It was absent or confined to the last lateral intercostal space in 120 of 129 patients with normal chest X-ray (specific- ity of 93.0%).”

Rationale

Approaches to Lung scanning1. Screening tool - ED

2 - 8 views (3 minutes)

2. Blue Protocol –ICU

(multisystem views)

3. Detailed inspection –

Resp Physicians

28 views(30 minutes)

4. Endobronchial/Contrast studies.

LUS as a screening tool

Resp/Med equivalent of FAST Tells you that there is extra-vascular

lung water/thickening( >400ml ) Tells you distribution Tells you rough quantity Does NOT tell you what sort Does NOT tell you how old

Limits of the SCREENING TOOL

DOES NOT interrogate post/basal CAN NOT interrogate hilum Does not consider asymmetry You still have to ‘be a doctor’

(quoting Justin Bowra for the umpteenth time)

Diagnostic accuracy 85%

Doctor + CXR > diagnostic accuracy 72%

STEPPING STONE

SAFE for novices Dichotomous question Feasible/storable/auditable

Experience informs interpretation MANY extra signs In expert hands, better than CXR

(Zanobetti M 2011, Xirouchaki N 2011)

AIM for today

Acquisition of standard protocol Interpretation using basic terminology Tweak the protocol Introduce the extra signs

Volpicelli G et al International evidence-based recommendations for point-of-care lung ultrasound, Intensive care med, 2012; 38: 577-591.

Acquisition

Focused exam – 8 views

Sagittal or coronal views RIB SHADOWS confirm position and guide you to pleura.

THE BAT VIEW

Rib shadow

Rib shadow

Chest wall

Pleural line

Rock the probe slightly side to side until the pleura is in sharp focus

Pleura not at right angles to probe so indistinct

Correct angle =

sharpest edge.

SIZE MATTERS (and focus)

SAME SPACE, SAME TIME, SAME PATIENT……….

F>

F>

F>

F>

The Regions

1 2

3

4

Volpicelli et al, Am J Emerg Med 2006; 24: 689-696

Region 2 is usually above the nipple

Interpretation

NORMAL LUNG

A = AIR , ASTHMA……

A lines = default normal Horizontal echo

reflection at exact multiples of intervals from surface to bright reflector.

Dry lung OR PNTX Decay with depth Obliterated by B

pleura A

A

A

A

A

A

B = BAD, BUBBLY

B lines = fluid in alveolus or interstitium

Originates from pleural line

Reaches base of screen OR ALMOST

MORE THAN 2 at once is abnormal

EXCEPT in lung base

Remember as ‘Kerley Bs’

Not exactly the same.

RIB RIB

B B B BB

B Lines = Crackles

Confluent B lines = Bad Bad ‘White’ or ‘shining’

lung Means increased

severity Probably indicates

thicker fluid in alveoli eg protein or inflammatory cells

% space / 10

C = COMPLICATED, CRINKLY, CRUD…..

CARDIAC……………..

C = Pleural line abnormalities

Acute inflammation Old fibrosis.

Indicates abnormal interstitium

Resistant to APO APO not excluded

RIB C

C can be grossly abnormal

If CCF is clinically likely, need to cross

check with heart or IVC

view.RIB

PLEURAL LINE ABNORMALITIES

OBVIOUS SUBTLE

B x 3 x 2 x 2 = CCF

Makes assumption that ‘globally’ wet lungs are most likely to be CCF

PER V

IEW

ZONES

SIDES

12

CASE A. RIGHT LUNG

CASE A. LEFT LUNG

XRAY A

Case B RIGHT LUNG

Case B LEFT LUNG

XRAY B

False Positive False negative Global fibrosis Bilateral

pneumonitis ARDS

Resolving CCF (pleural effusions)

Low focus Dual diagnosis

Tweaks

‘DRY’ BY PROTOCOL

POSSIBLE PE, LOOK FOR SUBPLEURAL ABNORMALITIES

?RESOLVING APO, LOOK FOR PLEURAL EFFUSIONS

‘WET’ BY PROTOCOL

RIGHT HEART LARGER THAN LEFT > ?FIBROSIS

LOOK FOR COLLAPSING IVC > ? pneumonia

View IVC for fluid tolerance

EXTRA SIGNS….

SUB-PLEURAL ABNORMALITIES

CONSOLIDATION OR COLLAPSE

SUB PLEURAL FLUID

Pneumonia with air bronchograms

..pneumonias, PE, mets….

HEPATISATION VS COLLAPSE

SOLID, NO CHANGE WITH RESPIRATION

COLLAPSE – CONCAVE EDGES, CHANGE WITH RESPIRATION

PLEURAL EFFUSIONS

VERY BIG MEDIUM

Pneumothorax

Normal Lung Pneumothorax

M-mode for sliding - normal

straight

speckled

No sliding – PNTX or Adhesion

straight

straight

No sliding- PNTX or adhesion

VERY SENSITIVE, LESS SPECIFIC

WALL MOTIONARTIFACT

PLEURA

straight

speckled

Additional PNTX signs

LUNG PULSE

NO PNTX

LUNG POINT

PNTX OR ADHESION

Sliding traps

BREATH HOLD NO BREATH HOLD

Recap

Terminology?

= 12 B lines Good scan?

= Rib shadow, sharp pleura and high focus Errors?

=15% with pre-existing fibrosis, dual pathology or resolving APO.

Summary

Lung scanning is easy Cheap/quick/safe/portable International acceptance

8 views/12 B lines Not infallible : 85% DA Better than auscultation + CXR