Ortho Surgeries Flashcards
induction plan for any patient presenting for acute fracture repair
RSI - always consider full stomach
why might arthritic pts be difficult intubations?
may have limited ROM of neck
what is rheumatoid arthritis
immune-related, progressive inflammation of synovial joints
(not just normal wear & tear)
airway concerns for a pt with rheumatoid arthritis
cervical mobility (atlantoaxial joint instability/subluxation), TMJ issues may make intubation difficult
why do pts with rheumatoid arthritis need to have pre-op c-spine films?
to evaluate atlantoaxial subluxation and determine if awake fiberoptic intubation is indicated
when is awake fiberoptic intubation indicated for pt with rheumatoid arthritis?
c spine film reveals > 5 mm instability
s/s cricoarytenoid arthritis in pt with RA
hoarseness
considerations for an RA pt on chronic NSAIDs
potential for GI bleeding, renal toxicity, platelet dysfunction
CV effects of rheumatoid arthritis
- pericardial thickening, effusions
- myocarditis
- coronary arteritis
- conduction defects
- cardiac valve fibrosis
heme effects of RA
- anemia
- platelet dysfunction
- thrombocytopenia
endocrine effects of RA
- adrenal insufficiency r/t steroid use
- impaired immune system
derm effects of RA
thin, atrophic skin from steroids
position most associated with air embolus
sitting (beach chair)
use of regional anesthesia in ortho surgeries
- more for upper extremity surgeries
- can be used with GA for postop pain control
- may result in less blood loss
possible patient positions for shoulder surgeries
lateral or beach chair
positioning challenge of shoulder surgery, regardless of position
padding and protection of ears, eyes, bony areas
~DuH~
can LMA be used for shoulder surgeries?
DFort says yes
regional anesthetic used in shoulder surgery for post op pain control
interscalene block
risks assoc. with controlled hypotension in shoulder surgeries
- beach chair position - cerebral ischemia
- vision loss
where does the art line need to be leveled to estimate CPP?
what is this area called?
level of external auditory meatus and tragus
circle of willis
why is the pressure in the circle of willis lower than the pressure at the level of the heart?
d/t vertebral column and hydrostatic pressure difference
1.25 cm = ____ mmHg drop in BP
1
benefits of arthroscopic surgeries
- less invasive, less blood loss
- less post-op discomfort
- reduced length of rehab
why is controlled hypotension used in arthroscopic surgeries?
to maintain bloodless field and reduce BP on non-tourniquet joints to optimize surgical field
why are irrigant fluids used in arthroscopic surgeries?
at what pressure are they instilled?
used to distend operative joint
60-80 mmHg
100-120 mmHg in beach chair
complications of high irrigation pressures with long duration
(in arthroscopy)
sub-q emphysema
tension pneumothorax
complications of irrigant absorption in arthroscopic surgeries
(book)
- fluid volume overload
- CHF
- pulmonary edema
- hyponatremia if sterile water used
most spinal surgeries involve what segments of the spine?
cervical & lumbar
anesthetic technique for spinal surgery
GA with or without paralysis
may do without paralysis to use SSEP
what aspects of spinal surgery can create airway challenges?
prone position
cervical immobility
why might the surgeon ask you to give VCM in the middle of a spinal surgery?
after CSF leak is repaired - increased transthoracic pressure allows the surgeon to test the seal of the dura
possible pt positions for cervical spine surgery
prone, sitting, or supine
(Fort says most are supine now)
potential airway management challenge for c spine surgery pts
TMJ dysfunction, atlantoaxial instability (limited neck ROM)k
surgical approach for C1-C2 vs. C3-C6
C1-2: probably posterior
C3-6: anterior
why use an ear pulse ox in c spine surgery
major arteries and veins are nearby - retractors could occlude carotid
pulse ox waveform/reading can give clues about carotid occlusion
why is dexamethasone given prophylactically to c spine surgery pts
prevent post op airway swelling
possible nerve injury in c spine surgery
recurrent laryngeal nerve
why is an LTA kit indicated for c spine surgery pts?
to prevent coughing or bucking and prevent potential for airway hematoma
typical position for lumbar spine surgery
prone
potential nerve injury with positioning for lumbar surgery
how to avoid?
brachial plexus
arms/shoulders < 90 degrees
why might you see decreased CO in a pt undergoing lumbar spine surgery?
abdominal compression (prone) can occlude IVC and impede venous return/stroke volume
why are FRC and Vt decreased in lumbar spine surgeries
prone position - diaphragm is cephalad
spinal surgeries assoc. with large blood loss
- lumbar spine
- spinal fusion
- hip replacement
respiratory concerns for a spinal fusion patient
scoliois pts may have restrictive lung disease
what is the artery of Adamkiewicz? (google)
why do we care
dominant thoracolumbar segmental medullary artery that supplies the lower spinal cord
need neuromuscular montioring in spinal fusion bc its v close to the spine
why use a toe pulse ox in a supine spinal surgery
to monitor vessel occlusion by retractors
typical patient population seen for hip fracture
elderly, frail, debilitated, dehydrated pts with existing comorbid conditions
positioning for hip fracture repair
- supine
- moved to fracture table after induction
- ipsilateral arm placed on chest
respiratory concerns related to positioning for a hip fracture repair
arm positioning creates restrictive lung conditions
ALIF vs. PLIF
- anterior or posterior lumbar interbody fusion
- can be done for cervical, thoracic, and lumbar spinal issues
if you give a hypobaric LA solution via spinal to a hip fracture pt, where will its effects be seen?
sorry prob a shitty way to word that
non-dependent (surgical) hip
is this supposed to say hypobaric- yup oopsie
fat embolisms are common for what procedures
hip fractures
long bone fractures (femur, tibia)
typical hip replacement patient
elderly, likely arthritic/degenerative joint disease
per the book, 50% are obese
positioning for hip replacement
lateral decubitus
why is a subarachnoid block particularly helpful in a hip replacement surgery?
(book)
several large muscle groups have to be cut/dissected to get to joint - muscle relaxation from block helps
why would a bilateral hip surgery be contraindicated?
if declining pulmonary function occurs after the first hip surgery
which is more painful - knee or hip replacement
knee, apparently
surgeries with high incidence of DVT
THA and TKA
(total hip/knee arthroscopy)
regional anesthetic options for a knee replacement
- femoral 3 in 1 block combined with spinal
- femoral catheter for post-op pain control
which is probably better for a closed reduction - succs or roc?
succs - usually very short procedures but muscle relaxation needed bc muscle contraction can prevent reduction
but i guess if you have sugammadex it don’t matta
anesthetic technique for closed reduction
can be done with propofol bolus
short-acting NMB
often done via mask ventilation w/o airway instrumentation
what is methylmethacrylate cement?
used to bind prosthetic to bone
what causes bone cement to harden against prosthetic components?
an exothermic reaction
what does intramedullary mean?
~google :)~
in the bone marrow
what can cause embolization of fat, bone marrow, cement, and air into venous channels?
intramedullary HTN
(>500 mmHg per M&M)
AEs of systemic bone cement absorption
- vasodilation
- decreased SVR
- release of tissue thromboplastin
- platelet aggregation
- microemboli formation
- embolic shock
what ortho surgeries should pregnant CRNAs not be involved in
ones that use bone cement
but prob all of em bc of the radiation
s/s of bone cement implantation syndrome
- hypotension
- hypoxia
- decreased CO
- dysrhythmias
- shunt
- pHTN
what might be the first sign of bone cement implantation syndrome under GA?
(book)
abrupt decrease in ETCO2
risk factors for bone cement implantation syndrome
(book)
- preexisting CV disease
- preexisting pHTN
- ASA 3+
- NY Heart Assoc. class 3 & 4
- intertrochanteric fracture
- long-stem arthroplasty
management of suspected bone cement implantation syndrome
100% FiO2
hydration
what is a pneumatic tourniquet
applied to an extremity proximal to surgical site to create a bloodless field
what is an Esmarch bandage?
~*google again~*
a soft rubber band used to expel venous blood from a limb (exsanguinate) that has had its arterial supply cut off by a tourniquet
AE of exsanguination of a lower extremity & tourniquet inflation
(M&M)
rapid shift of blood volume into central circulation
cuff overlap for pneumatic tourniquet
should be 180 degrees from nerve bundle
what determines inflation pressure of a pneumatic tourniquet?
what pressures are typically used
blood pressure
typically: lower ext. 100 mmHg & upper extremity 50 mmHg greater than SBP
what is a venous tourniquet?
I think it is when BP gets higher and allows arterial blood to get back into the extremity that is supposed to be bloodless but then the venous pressure isnt high enough for it to get back out so it builds up in there
Very scientific words i know
risk factors for neurological damage from pneumatic tourniquet
- > 2 hours tourniquet time
- overlap is over nerve bundle
physiologic effects of pneumatic tourniquet inflation
- autotransfusion = rise in SVR, CVP, PVR
- 300-500 mL displaced blood volume from exsanguination
- prolonged inflation = increased HR and BP
physiologic effects of pneumatic tourniquet deflation
- metabolic acidosis
- inc HR
- dec temp
- hypotension
why might you give neosynephrine prior to pneumatic tourniquet release
to prevent BP drop assoc. with anaerobic metabolites returning to tissues and into central circulation
why is tourniquet release assoc. with hypotension
sudden reduction of SVR (and PVR)
neuro effect of > 60 min of tourniquet
box 38-1
tourniquet pain
HTN
neuro effect of > 2 hours of tourniquet time
box 38-1
postop neuropraxia
how long does it take for cellular hypoxia to develop with a limb tourniquet?
box 38-1
within 2 min
what happens to cellular creatinine level with extremity tourniquet
box 38-1
decreases
when does endothelial capillary leak occur with limb tourniquet use?
box 38-1
> 2 hours
systemic effects of tourniquet release
box 38-1
- transient fall in core temp
- transient metabolic acidosis
- acid metabolites released into central circulation
- transient fall in pulmonary and systemic arterial pressures
- transient increase in ETCO2
when does tourniquet pain usually begin?
an hour after inflation
do IV analgesics help with tourniquet pain?
what route do they work?
nope, sucks
work when added to LA
deflating the tourniquet for how long can help with pain
10-15 min
unmyelinated, slow-conducting fibers
C fibers
fibers responsible for pinprick, tingling after tourniquet deflation
A delta
describe the pain assoc. wtih pneumatic tourniquets
burning, dull, aching, throbbing
*~so all the possible words to describe pain?~*
fat embolism triad
petechiae - axillary, subconjunctival
dyspnea
confusion, AMS
what causes impaired pulmonary perfusion r/t a fat embolus?
fat globules released into the blood cause pulmonary congestion
when does the fat embolus triad occur?
12-24 hours later
CV changes that may be seen with fat embolus
tachycardia, ST segment changes
pts at greatest risk for fat embolus
coexisting lung disease
treatment of fat embolus
O2, aggressive ventilation, fluids, steroids
anesthetic technique that reduces the risk of DVT
why?
epidural or spinal
higher levels of plasminogen and plasminogen activators, hyperkinetic blood flow, earlier ambulation
why is dead space ventilation seen with fat embolus
embolic material can qedge in pulmonary artery and block perfusion to lungs
why might you see acidosis assoc. with fat embolus
decreased BP results in inadequate perfusion + decreasd PO2 and tissue hypoxia
all those things result in anaerobic cellular respiration and lactic acid buildup
electrolyte abnormality assoc. with fat embolus
hyperkalemia
