5 scanning for dvt
DESCRIPTION
Scanning for DVTTRANSCRIPT
![Page 1: 5 scanning for dvt](https://reader033.vdocument.in/reader033/viewer/2022042507/554b5d1eb4c905793d8b500a/html5/thumbnails/1.jpg)
1
DVT ultrasoundSAH & RNSH 2011
Critical Care Ultrasound CourseThanks to Cindy Lucas… and yet again to
Daniel Lichtenstein
![Page 2: 5 scanning for dvt](https://reader033.vdocument.in/reader033/viewer/2022042507/554b5d1eb4c905793d8b500a/html5/thumbnails/2.jpg)
DVT! Anatomy ! Below knee DVT?! Compression US:
! Technique! Sites
! What the scan can tell you! Pitfalls
![Page 3: 5 scanning for dvt](https://reader033.vdocument.in/reader033/viewer/2022042507/554b5d1eb4c905793d8b500a/html5/thumbnails/3.jpg)
Anatomy of the deep veins
![Page 4: 5 scanning for dvt](https://reader033.vdocument.in/reader033/viewer/2022042507/554b5d1eb4c905793d8b500a/html5/thumbnails/4.jpg)
Anatomy of the deep veins
Below the knee!Anterior tibial!Posterior tibial!Peroneal!Gastrocnemial!Soleal
!Variable !Paired !Tricky!!Relevance of DVT?
Above the knee! Popliteal Vein in popliteal
fossa! From confluence of 3 calf
veins! To adductor canal! (Superficial) Femoral! Profunda Femoris joins
4cm below inguinal ligament
! Common Femoral! Long/ great saphenous
![Page 5: 5 scanning for dvt](https://reader033.vdocument.in/reader033/viewer/2022042507/554b5d1eb4c905793d8b500a/html5/thumbnails/5.jpg)
Here’s the problem
It would be nice to scan the below knee veins
!Incr sensitivity!Incr accuracy
!Variable !Paired !Tricky!!Relevance of DVT?
But it’s hard!! Variable! Paired! Tiny! Tricky! And most of them don’t
ermbolize! (But some do…)
![Page 6: 5 scanning for dvt](https://reader033.vdocument.in/reader033/viewer/2022042507/554b5d1eb4c905793d8b500a/html5/thumbnails/6.jpg)
6
Previous top tip: just look for above knee
Leave the calves to the sonographers!
![Page 7: 5 scanning for dvt](https://reader033.vdocument.in/reader033/viewer/2022042507/554b5d1eb4c905793d8b500a/html5/thumbnails/7.jpg)
But Lichtenstein came up with a solution
! Except for the anterior tibials, the below knee veins travel all in a line, a couple cm below the interosseous membrane
! together with their arteries: 2 veins for each artery = 6 vessels, all lined up
! We can see them from the front of the leg!! Probe between the tibia & fibula
![Page 8: 5 scanning for dvt](https://reader033.vdocument.in/reader033/viewer/2022042507/554b5d1eb4c905793d8b500a/html5/thumbnails/8.jpg)
8
Now we have 2 options
1. Just above knee: leave the calves to the sonographers!
2. Below knee (anterior approach)
![Page 9: 5 scanning for dvt](https://reader033.vdocument.in/reader033/viewer/2022042507/554b5d1eb4c905793d8b500a/html5/thumbnails/9.jpg)
9
DVT scan:Technique
![Page 10: 5 scanning for dvt](https://reader033.vdocument.in/reader033/viewer/2022042507/554b5d1eb4c905793d8b500a/html5/thumbnails/10.jpg)
Probe & preset?
! Ideally linear probe / vein preset! But curved probe / FAST preset works
too! Don’t need Doppler
![Page 11: 5 scanning for dvt](https://reader033.vdocument.in/reader033/viewer/2022042507/554b5d1eb4c905793d8b500a/html5/thumbnails/11.jpg)
Compression US
! Probe in transverse position! Just squash the vein!! If it squashes easily & completely, there
is no DVT! If it doesn’t, there’s a DVT
![Page 12: 5 scanning for dvt](https://reader033.vdocument.in/reader033/viewer/2022042507/554b5d1eb4c905793d8b500a/html5/thumbnails/12.jpg)
![Page 13: 5 scanning for dvt](https://reader033.vdocument.in/reader033/viewer/2022042507/554b5d1eb4c905793d8b500a/html5/thumbnails/13.jpg)
![Page 14: 5 scanning for dvt](https://reader033.vdocument.in/reader033/viewer/2022042507/554b5d1eb4c905793d8b500a/html5/thumbnails/14.jpg)
Normal veins ! Completely compressible! Press hard enough to just indent the
artery
![Page 15: 5 scanning for dvt](https://reader033.vdocument.in/reader033/viewer/2022042507/554b5d1eb4c905793d8b500a/html5/thumbnails/15.jpg)
Features of DVT! Gold standard sign: vein not completely
compressible! You might see thrombus! Vein might fail to augment on Doppler
![Page 16: 5 scanning for dvt](https://reader033.vdocument.in/reader033/viewer/2022042507/554b5d1eb4c905793d8b500a/html5/thumbnails/16.jpg)
16
Test
![Page 17: 5 scanning for dvt](https://reader033.vdocument.in/reader033/viewer/2022042507/554b5d1eb4c905793d8b500a/html5/thumbnails/17.jpg)
DVT?
![Page 18: 5 scanning for dvt](https://reader033.vdocument.in/reader033/viewer/2022042507/554b5d1eb4c905793d8b500a/html5/thumbnails/18.jpg)
DVT?
![Page 19: 5 scanning for dvt](https://reader033.vdocument.in/reader033/viewer/2022042507/554b5d1eb4c905793d8b500a/html5/thumbnails/19.jpg)
DVT?
![Page 20: 5 scanning for dvt](https://reader033.vdocument.in/reader033/viewer/2022042507/554b5d1eb4c905793d8b500a/html5/thumbnails/20.jpg)
DVT?
![Page 21: 5 scanning for dvt](https://reader033.vdocument.in/reader033/viewer/2022042507/554b5d1eb4c905793d8b500a/html5/thumbnails/21.jpg)
DVT?
![Page 22: 5 scanning for dvt](https://reader033.vdocument.in/reader033/viewer/2022042507/554b5d1eb4c905793d8b500a/html5/thumbnails/22.jpg)
DVT?
![Page 23: 5 scanning for dvt](https://reader033.vdocument.in/reader033/viewer/2022042507/554b5d1eb4c905793d8b500a/html5/thumbnails/23.jpg)
DVT?
![Page 24: 5 scanning for dvt](https://reader033.vdocument.in/reader033/viewer/2022042507/554b5d1eb4c905793d8b500a/html5/thumbnails/24.jpg)
Compression US! Pros ! Easy! Rapid ! B mode only! 98% sensitive
Cons! Misses external iliac
DVT! Misses small non-
occlusive DVT
![Page 25: 5 scanning for dvt](https://reader033.vdocument.in/reader033/viewer/2022042507/554b5d1eb4c905793d8b500a/html5/thumbnails/25.jpg)
23
Which sites can I compress?
![Page 26: 5 scanning for dvt](https://reader033.vdocument.in/reader033/viewer/2022042507/554b5d1eb4c905793d8b500a/html5/thumbnails/26.jpg)
Which sites can I compress?
! Internal Jugular V! Subclavian V! IVC! Saphenofemoral confluence (up fem)! Lower (superf) femoral near adductor hiatus! Long saphenous V! Short saphenous V! Popliteal vein & trifurcation! Beloe knee veins
![Page 27: 5 scanning for dvt](https://reader033.vdocument.in/reader033/viewer/2022042507/554b5d1eb4c905793d8b500a/html5/thumbnails/27.jpg)
Which sites should I compress?
! Up to you! The more veins you scan, the more sensitive
you are… eg UL veins add 4% in PE! The fewer you scan, the less irritating it is! 3-point scan is reasonable
1. Upper femoral (confluence)2. Lower femoral (near adductor hiatus)3. Popliteal (irritating if supine) …or …below knee
(weird at first)
![Page 28: 5 scanning for dvt](https://reader033.vdocument.in/reader033/viewer/2022042507/554b5d1eb4c905793d8b500a/html5/thumbnails/28.jpg)
1: Groin
! Probe in transverse position! Start just below inguinal ligament! ‘Mickey Mouse’ sign
! Femoral A! Saphenofemoral confluence! Then compress
![Page 29: 5 scanning for dvt](https://reader033.vdocument.in/reader033/viewer/2022042507/554b5d1eb4c905793d8b500a/html5/thumbnails/29.jpg)
![Page 30: 5 scanning for dvt](https://reader033.vdocument.in/reader033/viewer/2022042507/554b5d1eb4c905793d8b500a/html5/thumbnails/30.jpg)
![Page 31: 5 scanning for dvt](https://reader033.vdocument.in/reader033/viewer/2022042507/554b5d1eb4c905793d8b500a/html5/thumbnails/31.jpg)
![Page 32: 5 scanning for dvt](https://reader033.vdocument.in/reader033/viewer/2022042507/554b5d1eb4c905793d8b500a/html5/thumbnails/32.jpg)
![Page 33: 5 scanning for dvt](https://reader033.vdocument.in/reader033/viewer/2022042507/554b5d1eb4c905793d8b500a/html5/thumbnails/33.jpg)
![Page 34: 5 scanning for dvt](https://reader033.vdocument.in/reader033/viewer/2022042507/554b5d1eb4c905793d8b500a/html5/thumbnails/34.jpg)
2: insertion of LSV / GSV
![Page 35: 5 scanning for dvt](https://reader033.vdocument.in/reader033/viewer/2022042507/554b5d1eb4c905793d8b500a/html5/thumbnails/35.jpg)
2: insertion of LSV / GSV
![Page 36: 5 scanning for dvt](https://reader033.vdocument.in/reader033/viewer/2022042507/554b5d1eb4c905793d8b500a/html5/thumbnails/36.jpg)
3: fem V just above knee
! Adductor hiatus! Medial to the bone ! Hand behind, presses forward
![Page 37: 5 scanning for dvt](https://reader033.vdocument.in/reader033/viewer/2022042507/554b5d1eb4c905793d8b500a/html5/thumbnails/37.jpg)
![Page 38: 5 scanning for dvt](https://reader033.vdocument.in/reader033/viewer/2022042507/554b5d1eb4c905793d8b500a/html5/thumbnails/38.jpg)
![Page 39: 5 scanning for dvt](https://reader033.vdocument.in/reader033/viewer/2022042507/554b5d1eb4c905793d8b500a/html5/thumbnails/39.jpg)
![Page 40: 5 scanning for dvt](https://reader033.vdocument.in/reader033/viewer/2022042507/554b5d1eb4c905793d8b500a/html5/thumbnails/40.jpg)
![Page 41: 5 scanning for dvt](https://reader033.vdocument.in/reader033/viewer/2022042507/554b5d1eb4c905793d8b500a/html5/thumbnails/41.jpg)
![Page 42: 5 scanning for dvt](https://reader033.vdocument.in/reader033/viewer/2022042507/554b5d1eb4c905793d8b500a/html5/thumbnails/42.jpg)
![Page 43: 5 scanning for dvt](https://reader033.vdocument.in/reader033/viewer/2022042507/554b5d1eb4c905793d8b500a/html5/thumbnails/43.jpg)
4: popliteal fossa
! Lie patient on side, or lift leg! Popliteal vein
! Superficial to popliteal artery! visualise bone beneath! follow it to the trifurcation
![Page 44: 5 scanning for dvt](https://reader033.vdocument.in/reader033/viewer/2022042507/554b5d1eb4c905793d8b500a/html5/thumbnails/44.jpg)
![Page 45: 5 scanning for dvt](https://reader033.vdocument.in/reader033/viewer/2022042507/554b5d1eb4c905793d8b500a/html5/thumbnails/45.jpg)
![Page 46: 5 scanning for dvt](https://reader033.vdocument.in/reader033/viewer/2022042507/554b5d1eb4c905793d8b500a/html5/thumbnails/46.jpg)
![Page 47: 5 scanning for dvt](https://reader033.vdocument.in/reader033/viewer/2022042507/554b5d1eb4c905793d8b500a/html5/thumbnails/47.jpg)
![Page 48: 5 scanning for dvt](https://reader033.vdocument.in/reader033/viewer/2022042507/554b5d1eb4c905793d8b500a/html5/thumbnails/48.jpg)
![Page 49: 5 scanning for dvt](https://reader033.vdocument.in/reader033/viewer/2022042507/554b5d1eb4c905793d8b500a/html5/thumbnails/49.jpg)
5: below the knee
! Supine patient! Probe transverse! Between tibia & fibula
![Page 50: 5 scanning for dvt](https://reader033.vdocument.in/reader033/viewer/2022042507/554b5d1eb4c905793d8b500a/html5/thumbnails/50.jpg)
![Page 51: 5 scanning for dvt](https://reader033.vdocument.in/reader033/viewer/2022042507/554b5d1eb4c905793d8b500a/html5/thumbnails/51.jpg)
![Page 52: 5 scanning for dvt](https://reader033.vdocument.in/reader033/viewer/2022042507/554b5d1eb4c905793d8b500a/html5/thumbnails/52.jpg)
![Page 53: 5 scanning for dvt](https://reader033.vdocument.in/reader033/viewer/2022042507/554b5d1eb4c905793d8b500a/html5/thumbnails/53.jpg)
Handy Hints as you go down the leg
1. Decrease greyscale (dynamic range)2. Decrease frequency3. Increase depth as you go4. Obese: change to curved probe5. Sit with legs over bed / stand up6. Valsalva (humming works)7. Doppler …
![Page 54: 5 scanning for dvt](https://reader033.vdocument.in/reader033/viewer/2022042507/554b5d1eb4c905793d8b500a/html5/thumbnails/54.jpg)
Pitfalls
! Duplicate venous systems (duplex popliteal up to 35%)
! Non occlusive thrombus! LSV, SSV! Ant tibial veins! However … ‘90% = 100%’
![Page 55: 5 scanning for dvt](https://reader033.vdocument.in/reader033/viewer/2022042507/554b5d1eb4c905793d8b500a/html5/thumbnails/55.jpg)
One more time: Handy Hints ! You don’t need Doppler! You don’t need linear probe! But you won’t be 100%! Below-knee isn’t that hard! Sitting up / standing! Valsalva (humming works)
![Page 56: 5 scanning for dvt](https://reader033.vdocument.in/reader033/viewer/2022042507/554b5d1eb4c905793d8b500a/html5/thumbnails/56.jpg)
DVT US: Summary
! Compression US! Groin ! Just above knee! Below knee