Ortho Flashcards
What is the max time a tourniquet can be on and why?
2 hrs – leads to tissue hypoxia, acidosis. Capillary leak.
What is the UE max for tourniquet pressure?
250 mmHg (70-90 over SBP)
What is the LE max for tourniquet pressure?
300 mmHg (2x SBP)
What happens when you deflate tourniquet?
acidosis, hyperK, myoglobinemia, myoglobinuria, renal failure, hemodynamic changes, pulse ox changes, increased ETCO2, lower temp, lower pressures
When does tourniquet pain occur?
about 1 hr after applied. hard to tx, convert to general
What kind of pain does C fiber unmyelinated result in?
burning, ache
What kind of pain does A, C fiber myelinated result in?
prickle pain
When do you take down the tourniquet?
after dressing applied
What is tourniquet paresthesia due to?
stretching of the myelin
What kind of anesthesia do you use for arthroscopy usually?
LMA with general – it is usually outpt, so RA would last too long
What are some issues with UE arthroscopy?
PTX, SQ emphysema, pneumomediastinum. Beach chair positioning issues. Fluid irrigation – can add up, if using water it can lead to hyponatremia. PE d/t released thrombin in sinus.
What are some signs of PTX?
decreased O2, increased CVP, tachy, sweaty, tracheal deviation, JVD, increased airway pressures
Who are likely to get hemi/arthroplasty redo?
young males
Who are likely to get hemi/arthroplasty?
> 65 women
Who is at risk of increased morbidity with arthroplasty?
older males
Who is at risk of worse fx from arthroplasty?
older women
What is a good anesthetic plan for arthroplasty if HD stable?
spinal
Can you use N20 for arthroplasty?
NO d/t open bone
Is LMA good for arthroplasty?
NO because of positioning, usually need a lot of narcotic
What is a risk with joint disarticulation?
infection
What is the EBL of arthroplasty?
500-1000 mL
How do you prep for bone cement placement?
fluid load, FiO2 100%
Bone cement syndrome risk factors
CV dz, pHTN, ASA III+, NYHA III+, pathologic fx, intertrochanter fx, long bone (occurs in 2-17% of pt)
What is the 1st sign of bone cement syndrome, and then subsequent signs?
decreased ETCO2. then, decreased O2, decreased BP, arrhythmia, increased PVR, LOC if RA used, arrest even
What is bone cement syndrome d/t?
maybe emboli, complement activation?
How is bone cement syndrome treated?
as if R heart failure. Fluids, alpha agonists
What is normal VQ?
0.8 (4/5L)
What do you do if venous air embolism occurs and is known?
CV support, leave PEEP alone, NS/bone wax on field, aspirate via CVP line (doppler R 2nd ICS)
What are signs of VAE?
millwheel murmur, low CO2/O2/BP
What is the max level of spinal levels that can have kyphoplasty at one time?
2 bc of the cement
What do you need to have available if your pt is in prone?
bed in the hallway incase pt arrests, need to flip them
What do you do if they do anterior approach to spinal surgery?
it involves thoracotomy so have to use double lumen ETT
What is POVL due to?
retinal occlusion/ischemia, optic neuropathy
Who is at greatest POVL risk?
<18, >65, obese, male, Wilson bed, colloid use, EBL > 1 L, surgery > 5 hours, intraop hypotension, IOP > 40
When does POVL set in?
1-2 days postop. painless.
