1. Formulate the questiona. 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) 4
Should I give more fluids?• Lungs: wet or dry?• IVC: collapsing or distended? 7
Should I give more fluids? Wet lungs Dry lungs Distended IVC Small IVC … probably not …yes (NB look for ‘APO (but re-scan with everymimics’ eg fibrosis, and bag of IV fluid: if still‘fluid overload mimics’ shocked & B profile eg cor pulmonale) appears, cease fluids) 8
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. 9
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. 10
Recall: A lines versus B linesA lines B linesHorizontal artefacts Vertical artefactsOnly air is present Air/fluid mix in lungPresent in dry lungs Not seen in PTXPresent in PTX Even 1 B line rules out PTX at that site
B & B’ profile At least 3 B lines in all 4 anterior windows = wet lungsPleural sliding present = B profile = APOPleural sliding reduced /absent, irregular pleural line = B’ profile = disseminated pneumonia / ARDS
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
Recall: A/B profileThe windows show a mix of A & B =Patchy wet lung(s) (usu pneumonia)
Recall: C profileThe windows show anterior consolidation = Pneumonia ARDS (rarely: PE)Small amounts of consolidation = ‘irregular pleural line’
Step 1 findings One lung not Both lungs sliding slidingA’ profile B’ profile A profile B profile A/B or C profile
Step 1 findings One lung not Both lungs sliding slidingA’ profile: B’ profile: A profile: B profile: A/B or C PTX? Pneumonia Continue Pulmonary profile: Look for Treat. IVT Oedema Pneumonialung point, Treat. Continue consider IVT DDX. Step 2 Treat cause. Treat
Step 2 (after PTX ruled out) Single view of heart
Wait a minute!Do I need to scan the heart if I already have a diagnosis from the lung scan (PTX, pneumonia, APO)?
ControversialMost 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.
Step 2 (if lung sliding & B profile)This is usually acute cardiogenic pulmonaryoedema (APO). Occasionally severe bilateral pneumonia / ARDS can look like this. Fibrosis can look like this, but is usually limited to upper or lower lobes.
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 its 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, starttreating for APO, then proceed to focused TTE & reassess patient.
Back to the heart.What am I looking for? Tamponade? Massive PE? Hypovolaemia?
Step 2: single view heart• Using the curved probe, subcostal view is easiest• Probe transverse, marker to patients right• ID heart (probe angled cephalad)• Options if you cant obtain an adequate view: • Try different window (apical, parasternal) • Try different probe (phased array) • Get help 40
Step 2: single view heart (& dry lungs) Big RV Pericardial fluid Small volume Heart grossly InadequateSquashing LV heart NAD view ?
Step 2: single view heart (& dry lungs) Big RV Pericardial Small chambers or Inadequate heart grossly Squashing LV fluid normal viewPE (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
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)
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)
So proceed to step 3... ...if lungs are dry & no obvious PE or tamponadeBut be a doctor & synthesize the findings. 47
Step 3: dry lungs, small vol heart, IVCLarge IVC Anything else Inadequate<50% collapse Small IVC view Large IVC & collapsing ?
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 52
Anything else Small IVC <1.5cmCollapsing IVC >50% = fluid responsive Actions: Give IVT Proceed to step 4 53
Inadequate viewReconsider whether you really need the IVC information Actions: Either get help Or proceed to step 4 54
So: dry lungs, small vol heart, IVC… Large IVC Anything else Inadequate <50% collapse Small IVC, not collapsing view Large IVC, collapsingCaution with fluids Give fluids Get help or cut your Proceed to step 4 Proceed to step 4 losses Proceed to step 4
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) 56
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? 57
Step 4 Options: either/ both of:3-point compression DVT scan (is it a PE?) Abdomen (is it AAA? Free fluid?) 58
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
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. 60
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 61