spinal and epidural part 1 Flashcards
what is regional anesthesia divided into
spinal
epidural
caudal
combined spinal and epidural
what 2 meds discussed in lecture CANNOT be given via spinal
zofran
reglan
what are clinical indications of regional
sx involving lower abdomen, perineum, lower extremities
orthopedic surgery
vascular surgery on legs
thoracic surgery -epidural
c-section
neuraxial anesthesia reduces
narcotic usage
post op ileus
thromboembolic events
bleeding
PONV
respiratory complications
urinary retention
benefits of neuraxial anesthesia
great mental alertness
quicker to eat, void, and ambulate
avoid unexpected overnight admission from complications of general anesthesia
quicker PACU discharge
blunts stress response from surgery
relative contraindications of neuraxial anesthesia
deformities of spinal column
preexisting disease of spinal cord (MS, post polio)
chronic headache/backache
inability to perform SAB/ epidural after 3 attempts
absolute contraindications of neuraxial anesthesia
INR>1.5
plts <100,000 (trends)
nagelhout 2x normal
coagulation disorders or anticoagulants
pt refusal
evidence of dermal site infection
severe or critical valvular heart disease
HSS
operation>duration of LA
increased ICP
severe CHF
normal PT and what pathway
12-14 seconds
extrinsic
normal INR and pathway
0.8-1.1
extrinsic
aPTT normal and pathway
25-32 seconds
intrinsic
bleeding time normal
3-7 minuets
plt function
when would valvular heart disease be considered severe? critical?
severe- valve area 0.7-1.0 cm2
critical- valve area <0.7cm2
why is aortic stenosis a absolute contraindication for regional
decrease in SVR
in valvular aortic stenosis what is the life expectancy for a patient with angina? syncope? failure?
5 years
3 years
2 years
what is the death spiral
hypotension causes myocardial ischemia
ischemic contractile dysfunction
decreased CO
worsening hypotension
increased ischemia
severe CHF contraindication for regional would be when EF is
<30-40%
normal is 60
what is the onset for spinal? epidural?
spinal-rapid (5 min)
epidural-slow(10-15min)
what is the spread for spinal? epidural?
spinal- higher than expected may extend extracranially
epidural- as expected can be controlled with volume of LA
what is the nature of block for spinal? epidural?
spinal-dense
epidural-segmental
what is the motor block for spinal? epidural?
spinal-dense
epidural- minimal
hypotension is more likely in which regional anesthetic
spinal
what is the difference in duration for spinal and epidural
spinal is limited and fixed
epidural is unlimited
dosing of LA in spinal and epidural is based on
spinal- dosage
epidural- volume
in what type of regional is LA toxicity more common in
epidural
what is the anterior segment of the vertebra known as? posterior?
anterior-body
posterior - vertebral arch
what 2 structures link the anterior and posterior segments
lamina and pedicle
what is used as the landmark to find the middle line of the back
spinous process
cervical and thoracic spinous process require needle approach from
cephalic (above)
what are the symptoms of a facet joint injury
pain and muscle spasm in the area of skin severed by that nerve (dermatome)
inferior angle of scapula is located at
T7
superior aspect of iliac crest is located at
L4
posterior superior iliac spine is located at
S2
what is tuffiers line
intercristal line
horizontal line runs across the top edge of the hip bones and matches the L4 vertebra
in infants the intercristal line corresponds to
L5-S1
what is located at the base of the sacrum and aligns with S5 vertebra
sacral hiatus
what does the sacral hiatus act as an access point for
caudal anesthesia
what is the sacral cornua
landmark for caudal anesthesia
what is the conus medullaris and where does it end
spinal cord tapers off at the end
ends between L1 and L2
infants L3
what is the cauda equina
bundle of spinal nerves extending from conus medullaris to dural sac
where does the subarachnoid space end
dural sac
S2 in adults S3 in infants
filum terminale is
structure that continues downward from the end of spinal cord
continuation of pie mater
functions to anchor the spinal cord to the coccyx
where is the internal filum terminale
begins at the conus medullaris extending to dural sac
L1-S2
where is the external filum terminale
starts from the dural sac and extends into the sacrum
S2-S5
blood supply to the spinal cord includes
one anterior spinal artery originating from vertebral artery
two posterior spinal arteries originating from vertebral artery
anterior spinal artery syndrome can lead to
motor paralysis
loss of pain and temperature sensation below affected area
what are the 4 causes of ischemia discussed in lecture
low BP
mechanical blockage
blood vessel disease
bleeding
what supplies the lower 2/3 of spinal cord
artery of adamkewicz
arises from T7-9 and L2 regions
name the ligaments in ordered from posterior to anterior
supraspinous ligament
intraspinous ligament
ligamentum flavum
posterior longitudinal ligament
anterior longitudinal ligament
what ligaments are not included in a paramedic approach that would be in a midline
suprospinous ligament
intraspinous ligament
what is the order of layers in a midline approach for a spinal
skin
subq fat
supraspinous ligament
interspinous ligament
ligamentum flavum
dura mater
subdural space
arachnoid mater
subarachnoid space
when is a paramedian approach favorable
interspinous ligament calcified or patient cannot flex their spine
