Kylie Baker's guide to the basics of bedside lung ultrasound

1. Kylie Baker
Ipswich Hospital, Qld

2. 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

3. This talk:-
 Background
 Rationale- screening tool vs definitive.
 Acquisition
 Interpretation
 Tweaks

4. Background
The Comet-tail Artifact
An Ultrasound Sign of Alveolar-
Interstitial Syndrome
DANIEL LICHTENSTEIN, GILBERT MÉZIÈRE,
PHILIPPE BIDERMAN, AGNÈS GEPNER, and
OLIVIER BARRÉ
Service de Réanimation Médicale and Service de
Radiologie, Hôpital Ambroise-Paré, Boulogne (Paris),
and Service de Réanimation Polyvalente, Centre
Hospitalier Général, Saint-Cloud (Paris), France
AM J RESPIR CRIT CARE MED 1997;156:1640–1646.

5. International evidence-based
recommendations for point-of-care lung
ultrasound
Intensive Care Med
DOI 10.1007/s00134-012-2513-4
Giovanni Volpicelli Mahmoud Elbarbary Michael Blaivas
Daniel 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 Neri
Enrico Storti
Tomislav Petrovic
International Liaison Committee on Lung Ultrasound (ILC-LUS) for the
International
Consensus 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

6. “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

7. Approaches to Lung
scanning
1. 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.

8. 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

9. 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)

10. Diagnostic accuracy
85%
Doctor + CXR > diagnostic accuracy 72%

12. 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)

13. 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.

14. Acquisition

15. Focused exam – 8 views
Sagittal or coronal views RIB SHADOWS confirm
position and guide you to
pleura.

16. THE BAT VIEW
Chest wall
Pleural line

17. 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.

18. SIZE MATTERS (and focus)
SAME SPACE, SAME TIME, SAME PATIENT……….
F>
F>
F>
F>

19. The Regions
1 2
3
4
Volpicelli et al, Am J Emerg Med 2006; 24: 689-696
Region 2 is usually above the nipple

20. Interpretation

21. NORMAL LUNG

23. 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

25. 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

26. B Lines = Crackles

27. 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

29. C = Pleural line
abnormalities
 Acute inflammation
 Old fibrosis.
Indicates abnormal
interstitium
 Resistant to APO
 APO not excluded
RIB C

30. C can be grossly abnormal
If CCF is
clinically
likely, need to
cross check
with heart or
IVC view.RIB

31. PLEURAL LINE
ABNORMALITIES
OBVIOUS SUBTLE

32. B x 3 x 2 x 2 = CCF
Makes assumption that ‘globally’ wet
lungs are most likely to be CCF
12

33. CASE A. RIGHT LUNG

34. CASE A. LEFT LUNG

35. XRAY A

36. Case B RIGHT LUNG

37. Case B LEFT LUNG

38. XRAY B

39. False Positive False
negative
 Global fibrosis
 Bilateral
pneumonitis
 ARDS
 Resolving CCF
(pleural
effusions)
 Low focus
 Dual diagnosis

40. Tweaks

41. ‘DRY’ BY PROTOCOL
POSSIBLE PE, LOOK FOR
SUBPLEURAL
ABNORMALITIES
?RESOLVING APO, LOOK
FOR PLEURAL EFFUSIONS

42. ‘WET’ BY PROTOCOL
RIGHT HEART LARGER
THAN LEFT > ?FIBROSIS
LOOK FOR COLLAPSING
IVC > ? pneumonia

43. View IVC for fluid tolerance

44. EXTRA SIGNS….

45. SUB-PLEURAL
ABNORMALITIES
CONSOLIDATION OR
COLLAPSE
SUB PLEURAL FLUID

46. Pneumonia with air
bronchograms

47. ..pneumonias, PE, mets….

48. HEPATISATION VS
COLLAPSE
SOLID, NO CHANGE WITH
RESPIRATION
COLLAPSE – CONCAVE
EDGES, CHANGE WITH
RESPIRATION

49. PLEURAL EFFUSIONS
VERY BIG MEDIUM

50. Pneumothorax
Normal Lung Pneumothorax

51. M-mode for sliding - normal
straight
speckled

52. No sliding – PNTX or Adhesion
straight
straight

53. No sliding- PNTX or
adhesion
VERY SENSITIVE, LESS SPECIFIC
WALL
MOTION
ARTIFACT
PLEURA
straight
speckled

54. Additional PNTX signs
LUNG PULSE
NO PNTX
LUNG POINT
PNTX OR ADHESION

55. Sliding traps
BREATH HOLD NO BREATH HOLD

56. 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.

57. Summary
 Lung scanning is easy
 Cheap/quick/safe/portable
 International acceptance
 8 views/12 B lines
 Not infallible : 85% DA
 Better than auscultation + CXR