The document describes a protocol for using ultrasound to assess shock in patients. The protocol, called the "shock screen", is a 3-step process that involves scanning the lungs, heart, and inferior vena cava. An optional fourth step involves scanning other areas if the cause of shock remains unclear. The shock screen provides guidance on fluid resuscitation and helps exclude common causes of shock like pulmonary embolism or tamponade.

1. The shocked patient
Adapted from Lichtenstein's BLUE
points & FALLS protocol
(with permission)
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2. Summary
1 (Ongoing resus) Clinical assessment:
formulate the question
2 Rapid shock screen
3 Form a working diagnosis
4 Continue resuscitation
5 Re-scan / monitor progress / further
investigations
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3. 1. Formulate the question

4. 1. Formulate the question
a. Should I give more fluids? (Or inotropes,
or vasopressors?)
b. Why is the patient shocked?
The shock screen won’t tell you the diagnosis
every time, but it will tell you when not to
give IV fluids… or when to stop (B profile
appears)
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5. Why is the patient shocked?
• Obstructive (TPTX, massive PE,
tamponade)
• Cardiogenic
• Hypovolaemic (fluid loss, 3rd spacing…)
• Distributive (septic, anaphylactic,
neurogenic)
• Dissociative (CO, cyanide)
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6. Why is the patient shocked?
• Obstructive (TPTX, massive PE,
tamponade)
• Cardiogenic (lung rockets)
• Hypovolaemic (fluid loss, 3rd spacing…)
• Distributive (septic, anaphylactic,
neurogenic)
• Dissociative (CO, cyanide)
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7. Should I give more fluids?
• Lungs: wet or dry?
• IVC: collapsing or distended?
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8. Should I give more fluids?
Wet lungs Dry lungs
Distended IVC Small IVC
… probably not …yes
(NB look for ‘APO (but re-scan with every
mimics’ eg fibrosis, and bag of IV fluid: if still
‘fluid overload mimics’ shocked & B profile
eg cor pulmonale) appears, cease fluids)
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9. What if lungs dry & large IVC?
(or lungs wet & small IVC?)
A. Each sign has false positives & negatives.
Go back & reassess the patient, then
synthesize your findings.
=Be a doctor.
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10. What about large LA/LV?
Surely that suggests I should avoid IVT?
A. Not in isolation.
Even patients with dilated cardiomyopathy
can suffer hypovolaemic shock.
But be sensible & consider smaller boluses,
and correlate with other findings.
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11. 2. The shock screen

12. Curved probe, abdominal preset
• Machine settings: as for arrest screen
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13. A 3-step scan (plus 1)
1. Anterior lung fields (this time 2 points)
2. Single view heart
3. IVC (hypovolaemia / obstructive shock)
4. Take a step back & consider:
• Leg veins (obstructive: PE)
• Abdo (hypovol: AAA / free fluid)
• Other tests
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14. The shock scan
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15. The shock scan
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16. Step 1: anterior chest: upper & lower
BLUE points
• Probe sagittal, midclavicular line
• 2 spots on each side
• i.e. upper chest & lower chest
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17. Recall: upper & lower BLUE points
1 1
2 2
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18. Step 1 findings
One lung not Both lungs slidng
sliding
A’ profile B’ profile A profile B profile A/B or C
profile

19. Recall: A lines versus B lines
A lines B lines

20. Recall: A lines versus B lines
A lines B lines
Horizontal artefacts Vertical artefacts
Only air is present Air/fluid mix in lung
Present in dry lungs Not seen in PTX
Present in PTX Even 1 B line rules
out PTX at that site

21. A vs A’ profile: is sliding present?

22. A vs A’ profile: is sliding present?

23. A vs A’ profile: is sliding present?

24. A or A’ profile?

25. A or A’ profile?

26. A & A’ profile
A lines (or no lines) in all 4 lung windows
+
Pleural sliding present = A profile = dry lungs
Pleural sliding absent = A’ profile = PTX /
1 lung ventilation / other

27. B & B’ profile:
Multiple B lines = wet lungs
Multiple B lines = pulmonary oedema
APO = cardiogenic oedema
ARDS = non cardiogenic oedema
Pneumonia = local oedema

28. Note the difference w.r.t. pleural sliding
ARDS/ disseminated APO:
pneumonia: Transudate
Exudate Lung sliding is
Proteinaceous preserved, smooth
‘sticky’ pleural line
Reduced / absent lung B profile
sliding, irregular
pleural line
B’ profile

29. B or B’ profile?

30. B or B’ profile?

31. B or B’ profile?

32. B & B’ profile
At least 3 B lines in all 4 anterior windows
= wet lungs
Pleural sliding present = B profile = APO
Pleural sliding reduced /absent, irregular
pleural line = B’ profile = disseminated
pneumonia / ARDS

33. Is that 100% true?
No, but it’s close.
B profile + preserved lung sliding = almost
always APO.
B profile + absent sliding = almost always
pneumonia.
NB remember the 90% rule

34. Recall: A/B profile
The windows show a mix of A & B
=
Patchy wet lung(s) (usu pneumonia)

35. Recall: C profile

36. Recall: C profile
The windows show anterior consolidation
=
Pneumonia
ARDS
(rarely: PE)
Small amounts of consolidation = ‘irregular pleural line’

37. Step 1 findings
One lung not Both lungs sliding
sliding
A’ profile B’ profile A profile B profile A/B or C
profile

38. Step 1 findings
One lung not Both lungs sliding
sliding
A’ profile: B’ profile: A profile: B profile: A/B or C
PTX? Pneumonia Continue Pulmonary profile:
Look for Treat. IVT Oedema Pneumonia
lung point, Treat. Continue
consider IVT
DDX. Step 2 Treat cause.
Treat

39. Step 2 (after PTX ruled out)
Single view of heart

40. Wait a minute!
Do I need to scan the heart if I already have a
diagnosis from the lung scan (PTX,
pneumonia, APO)?

41. Controversial
Most of us would still scan heart to be sure.
Some wouldn’t.
(See APO note next slide)
This step only yields useful information if it demonstrates
obvious pathology: ie ‘rule in, not rule out’.
If negative, you will need to proceed to step 3.

42. Step 2 (if lung sliding & B profile)
This is usually acute cardiogenic pulmonary
oedema (APO). Occasionally severe bilateral
pneumonia / ARDS can look like this.
Fibrosis can look like this, but is usually
limited to upper or lower lobes.

43. If you saw B profile on step 1…
… and step 2 shows poor And step 2 shows ‘normal’ LV
LV function Still probably APO- start
= acute cardiogenic treating
pulmonary oedema (but re-check clinical picture
(APO) to be sure it's not severe
bilateral pneumonia /
ARDS)
LV failure commonly appears as spuriously 'normal' LV on
basic 2D echo. So if B profile but heart looks OK, start
treating for APO, then proceed to focused TTE & reassess
patient.

44. Back to the heart.
What am I looking for?
Tamponade?
Massive PE?
Hypovolaemia?

45. Step 2: single view heart
• Using the curved probe, subcostal view is easiest
• Probe transverse, marker to patient's right
• ID heart (probe angled cephalad)
• Options if you can't obtain an adequate view:
• Try different window (apical, parasternal)
• Try different probe (phased array)
• Get help
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46. Subcostal scan heart

47. Step 2: single view heart (& dry lungs)
Big RV Pericardial fluid Small volume Heart grossly Inadequate
Squashing LV heart NAD view
?

48. Step 2: single view heart (& dry lungs)
Big RV Pericardial Small chambers or Inadequate
heart grossly
Squashing LV fluid normal view
PE (probably) Tamponade Hypovolaemia/ sepsis?
(probably) Could still be PE!
Try another window
Consider Drainage IV fluid Try cardiac probe
thrombolysis
Proceed to step 3 Get help

49. Step 3
IVC

50. Hang on!
Do I need to scan the IVC if I already have a
diagnosis from steps 1 & 2?
(PTX, massive PE, tamponade, pneumonia,
APO)

51. Controversial
Not if Dx already obvious (eg tamponade).
Yes if Dx still unclear: dry lungs, small volume
heart (e.g. you haven’t ruled out PE yet)
But remember that IVC can be ‘falsely’ large
(eg cor pulmonale) and ‘falsely’ small (eg
XS probe pressure)

52. So proceed to step 3...
...if lungs are dry & no obvious PE or
tamponade
But be a doctor & synthesize the findings.
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53. Step 3: dry lungs, small vol heart, IVC
Large IVC Anything else Inadequate
<50% collapse Small IVC view
Large IVC & collapsing
?

54. IVC 1
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55. IVC 1
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56. IVC 2
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57. IVC 3 (transverse)
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58. IVC 3 (transverse)
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59. Large IVC (>2.3cm), <50% collapse
= elevated CVP
Multiple causes
…but probably not fluid responsive
Actions:
Reassess clinical picture
Consider other tests
Avoid indiscriminate IVT
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60. Anything else
Small IVC <1.5cm
Collapsing IVC >50%
= fluid responsive
Actions:
Give IVT
Proceed to step 4
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61. Inadequate view
Reconsider whether you really need the IVC
information
Actions:
Either get help
Or proceed to step 4
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62. So: dry lungs, small vol heart, IVC…
Large IVC Anything else Inadequate
<50% collapse Small IVC, not collapsing view
Large IVC, collapsing
Caution with fluids Give fluids Get help or cut your
Proceed to step 4 Proceed to step 4 losses
Proceed to step 4

63. Step 4
• Take a step back
• Have a think (& another look at the patient &
other information)
• What causes have I excluded?
• What else is left?
• Can bedside US help any further?
• Abdomen (hypovol: AAA / free fluid)
• Leg veins (obstructive: PE)
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64. Who needs step 4?
Anyone with:
Dry lungs, lung sliding present, diagnosis still
unclear, and…
***shock unresponsive to fluids***
Is it sepsis?
Is it a ruptured AAA?
Is it PE?
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65. Step 4
Options: either/ both of:
3-point compression DVT scan (is it a PE?)
Abdomen (is it AAA? Free fluid?)
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66. Step 4: dry lungs, diagnosis unclear,
shock unresponsive to IV fluids
3-point compression DVT seen
leg veins = PE
DVT not seen: AAA seen =
Scan the abdomen Ruptured AAA
Normal aorta
AAA ruled out
Now what?
PTO

67. Now what?
You’ve reached the end of the scan
Patient still shocked
Fluids didn’t work
You’ve ruled out cardiogenic, PTX,
tamponade
…but not PE.
If it’s still on your list, you need a different
test.
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68. But while arranging other tests…
Keep scanning the lungs
If lungs still dry, you can give more IV fluid
Once B profile appears or patient improves,
cease fluids
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69. Recap: the shock scan

70. A 3-step scan (plus 1)
1. Anterior lung fields (this time 2 points)
2. Single view heart
3. IVC (hypovolaemia / obstructive shock)
4. Take a step back & consider:
• Leg veins (obstructive: PE)
• Abdo (hypovol: AAA / free fluid)
• Other tests
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71. The shock scan
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72. The shock scan
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73. Further tests?
After resuscitation phase
If shock screen didn't suffice
If clinical picture demands it
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74. Summary
The shock screen won’t tell you the diagnosis
every time, but it will tell you when it’s
safe to give IV fluids (dry lungs & small
IVC)… or when to stop (wet lungs, large
IVC).
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