Need an acoustic step-off. Make by using 10x strength jello.
abscess or cellulitis (or vascular aneurysm)
cellulitis looks like cobblestones, muscle with slight fluid
Epidermis/dermis®hypodermis®subcutaneous fascia®muscle®bone(shadows)
Hypoechoic to anechoic, compressible, posteriro enhancement, no doppler flow
looks just like other side but with more swelling
you will see cobblestoning
abnormal thickening of fascia
irregularity
abnormal fluid collection along fascial plane (>4mm)
Look for the V which is where bone meets bone
Shoulder
go anterior
probe indicator horizontal
should see the biceps tendon in the bicipital groove
If there is fluid surrounding the tendon, then there is fluid in the joint
Knee
Go suprapatellar in longitudinal
will see the bursa which commicates with joint space, if more than a thin line then effusion
Hip
anterior oblique longitudinal on internally rotated leg
effusion if >5mm
Ankle
anterior tibiotalar recess
if capsule is displaced >3mm=effusion
Foreign Bodies
need stepoff pad
put dots on either side of the probe, can do it in 4 spots
Or put in transverse, use isosceles triangle rule. Measure distance down then go that far back and insert to 45 angle on either side of the probe while watching in real time. Then incise between the two needles.
Peritonsillar Abscess
use vaginal probe to get depth
then cut the needle cap to that length
Sinusitis
On maxillary sinus if you can see the apex of the sinus then there is sinusitis
Can also use waterbath to image extremities (The American Journal of
Emergency Medicine
Volume 22, Issue 7 , November 2004, Pages 589-593)
Standoffs:
Just heat some water and make a 10% solution of gelatin.
You don’t want to heat the water too much or you will burn the gelatin when you
add it.
Regular gelatin you make at home is less than 1% gelatin, you just need to
concentrate it more.
10% means 100 mg per cc of liquid.
For example, if you boil 1 liter of water, you need 100 gm of gelatin.
Just do the math for whatever amount you need.
You will need an electric mixer because this stuff is hard to dissolve, remember
you are making a super-saturated solution (I bet you haven’t heard that word
since the biochemistry days).
Don’t freeze it after you are done or it will crack, just put it in the
refrigerator.
It will last forever in the fridge, unless it contaminates.
Just make sure the container is airtight so no evaporation occurs.
I’ve left the gelatin blocks out of the fridge (I actually put them in the
closet), for about 5 days and they didn’t melt and nothing grew on them.
Gelatin is also used to make glue, so whatever container you use, make sure you
clean it off right away or you will be scrubbing for a long time.
The good news is that once you make the gelatin blocks, if they break you can
just re-melt them and use them again, no need to mix or anything.
Musculoskeletal Infections
(Clin Rad 2005;60:149)
Can use it for anterior stab wounds as well
Abscess
tensosynovitis
nec fasc
thrombosed vessel
Ultrasound-guided hip arthrocentesis in the ED (The American Journal of
Emergency Medicine Volume 25, Issue 1 , January 2007, Pages 80-86)
Before
you can finish saving the last image onto the machine for Q&A, your resident
has already called back the hand surgeon to inform him that he hasn't gotten
off the hook quite so easily this time. As you wheel your handy ultrasound
machine out of room 10, you can't help but marvel at how "quick and minor"
most problems can become with the help of bedside ultrasonography.
