Test 1 Travis Flashcards
(182 cards)
Adding this to LA for retrobulbar block may enhance spread.
This substance is a hydrolyser of connective tissue
Hyaluronidase
successful block of retrobulbar block will be marked by these three effects
anesthesia
akinesia
blockade of oculocephalic reflex
(this is the dolls eye reflex - when blocked your eyes will not continue staying midline/focused on one object when blocked so ur eyes will move with ur head turn in sync)
blockade of retroperitoneal block should not be performed in what 3 diseases
- bleeding disorder
- extreme myopia (produces elongate globe of eye - high risk for globe perforation
- open eye injuries (inc pressure behind eye - risk for extrusion of eye contact with LA inj)
blocking this nerve prevents squinting of eye
facial
three techniques of facial nerve block
van Lint
atkinson
O’brien
major complication of facial nerve block
SQ hemorrhage
name 3 peribulbar block sites
inferotemporal
superonasal
medial
in this ocular block you have profound analgesia but movement may still be present
sub-tenon block
tenon tissue fuses anteriorly with what structure
conjunctiva
tenon tissue encapsulates this structure posteriorly
globe
oculocariac reflex involves afferent ___ ____ nerve and efferent ____ ____ nerve.
afferent sensory trigeminal
efferent motor vagus nerve
these fibers have a short chronaxy bc of relatively low capacitance of their myelinated membrane
motor fibers
these fibers have a long chronaxy because of their higher capacitance of their non myelinated membranes
C Pain fibers
Short/Long duration is the best discriminator of distance btw needle and nerve
shorter
____ MHz best for shallow structures
____ MHz best for deeper
10-13 shallow
2-5 deep
US structures appearing
Black - high water content (vessels, local csf) are__
White - transmission blocked, bone, air are ___
Gray - intermediate density - organs
anechoic - ie big black vein on US
hyperechoic - ie whitest muscle nerve, bone
hypoechoic - organ
exhibiting this.. implies that the received echo varies up angle of insonation
anisotropy
transducer angle changes in image of US
best visualization of needle tip is when the bevel is oriented which way
directly toward or away from the transducer
why deep 90 degree insertions do not show up well i suppose?
this segment of the spinal cord provides for ventral rami of brachial plexus
C4 - T1
cervical enlargment
this segment of the spinal cord provides for lumbar and sacral plexus
L2 - L3
lumbar enlargment
CSF is produced by ___ ____ of cerebral ventricles
choroid plexus
CSF is reabsorbed by ____ _____ along the sagital sinus
arachnoid granulation
SAS space contains this much CSF
25 - 35 ml
some texts up to 80
total body CSF
100 - 150 ml