Regional Anesthesia - Valley Anesthesia: Questions And
Correct Answers
How may vertebrae are there? Right Ans - 33
What are the high points of the spinal canal? Right Ans - C3 & L3
What are the low points of the spinal canal? Right Ans - T6 & S2
Where does the SC extend from? Right Ans - The foramen magnum to
lumbar level 1 in adults & 3 in the newborn
The SC terminates at the _____ _____ & the _____ ____ extends down & anchors in
the lower sacral region. Right Ans - conus medullaris
filum terminale
There are ____ pairs of spinal nerves. Right Ans - 31
What is the nerve group in the lower dural sac? Right Ans - The cauda
equina (horses tail)
What ligament runs from the sacrum to C7? Right Ans - The supraspinous
ligament
What ligament runs the full length of the spinal column? Right Ans - The
interspinous ligament
Which ligament occurs in short segment between spinous processes? Right
Ans - The ligamentum flavum
The _____ _____ is the space that surrounds the spinal meninges. Right Ans -
epidural space
The epidural space extends from the ____ ____ to the _____ _____. Right Ans -
foramen magnum to the sacral hiatus
Which ligament binds the epidural space posteriorly? Right Ans - The
ligamentum flavum
,At what level is the epidural space the widest? Right Ans - L2
At what level is the epidural space the narrowest? Right Ans - C5
Where does the dura mater extend from? Right Ans - The foramen magnum
to S2-3 vertebrae
Where does the arachnoid end? Right Ans - S2
What space lies between the arachnoid & pia mater? Right Ans - The
subarachnoid space
The epidural space is a potential space that is bound by the ____ & _____ ____.
Right Ans - dura
ligamentum flavum
Where is the blood supply to the SC & nerve roots derived from? Right Ans
- A single anterior spinal artery & paired posterior spinal arteries
Where is the principle site of action for neuraxial blockade? Right Ans - The
nerve root
Most important factors in determining distribution of LAs for spinal
anesthesia Right Ans - Density
Dosage & volume injected
Position of the patient during & immediately after injection..other factors are
height, spine, needle angle, site of injection, dose, vol, baracity density, sg
Uptake of LA is greatest where the concentration of the LA is the ______.
Right Ans - greatest
What determines the level of a block? Right Ans - Position
How do all subarachnoid blocks work? Right Ans - By diffusion down a
concentration gradient
What does the rate of elimination determine? Right Ans - The duration of
spinal anesthesia
,How are LAs eliminated? Right Ans - By vascular absorption via
subarachnoid & epidural blood vessels
The more the LA is bound to lipids, the less chance there is for ____ ____.
Right Ans - vascular absorption
What will decrease the rate of elimination of LAs? Right Ans - Decreases in
SC blood flow
Vasoconstriction
What is the predominant action of sympathetic blockade due to? Right Ans
- Venodilation
What does venodilation result in? Right Ans - Reduced venous return, SV,
CO, & BP
What can occur is sympathetic outflow from T1-T4 is blocked by a LA?
Right Ans - Unopposed vagal stimulation will produce bradycardia
(Bainbridge reflex)
What is bradycardia associated w/? Right Ans - Blockade of the
cardioaccelerator fibers & decreased venous return
What occurs w/ the decrease in venous return & corresponding reduction in
right atrial filling? Right Ans - The frequency of action potentials from
stretch receptors to the RA & great veins is diminished -> a reflex decrease in
HR
What is the best means for treating hypotension during spinal analgesia?
Right Ans - Give IV fluids if not normovolemic
Give ephedrine if normovolemic
Why should glucose solutions be avoided in the treatment of hypovolemia?
Right Ans - Glucose acts as a diuretic & can worsen the situation
(hypotension)
What is the best drug of choice for symptomatic bradycardia & why? Right
Ans - A mixed alpha & beta agonist (ephedrine)
, It increases the HR & peripheral vascular resistance
What occurs w/ a high block (C2-C3)? Right Ans - Phrenic nerve paralysis
& loss of accessory muscle of ventilation -> hypoxia
What ventilatory changes occur w/ a high spinal? Right Ans - Decreased
FRC d/t paralysis of abdominal muscles
Apnea (d/t hypoperfusion of the respiratory centers in the medulla 2˚ to
severe hypotension)
At what level of blockade do patients start to feel dyspneic? Right Ans - T2-
T4
What is the advantage of spinal over epidural anesthesia? Right Ans - The
ability to control the spread of the anesthetic by controlling the specific
gravity of the solution & the position of the patient.
How can trauma to the dura be minimized in the sitting position? Right Ans
- Using a pencil point needle (separates the dura)
If using a cut-bevel, needle will need to face either left/right to separate
(rather than tear) the dura
How can trauma to the dura be minimized in the lateral position? Right Ans
- Using a pencil point needle (separates the dura)
If using a cut-bevel needle, the needle must face up or down
How long should ticlodipine (ticlid) be stopped prior to neuraxial anesthesia?
Right Ans - 14 days
How long should clopidogrel (Plavix) be stopped prior to neuraxial
anesthesia? Right Ans - 7 days
How long should LMWH (enoxaparin [lovenox]) be delayed postop to
decrease the risk of a spinal hematoma? Right Ans - 24 hrs
If postop LMWH will be used, epidural catheters should be removed _____ ____
prior to the 1st dose. Right Ans - 2 hrs.
T7 dermatome Right Ans - Inferior border of scapula (lower tip)
Correct Answers
How may vertebrae are there? Right Ans - 33
What are the high points of the spinal canal? Right Ans - C3 & L3
What are the low points of the spinal canal? Right Ans - T6 & S2
Where does the SC extend from? Right Ans - The foramen magnum to
lumbar level 1 in adults & 3 in the newborn
The SC terminates at the _____ _____ & the _____ ____ extends down & anchors in
the lower sacral region. Right Ans - conus medullaris
filum terminale
There are ____ pairs of spinal nerves. Right Ans - 31
What is the nerve group in the lower dural sac? Right Ans - The cauda
equina (horses tail)
What ligament runs from the sacrum to C7? Right Ans - The supraspinous
ligament
What ligament runs the full length of the spinal column? Right Ans - The
interspinous ligament
Which ligament occurs in short segment between spinous processes? Right
Ans - The ligamentum flavum
The _____ _____ is the space that surrounds the spinal meninges. Right Ans -
epidural space
The epidural space extends from the ____ ____ to the _____ _____. Right Ans -
foramen magnum to the sacral hiatus
Which ligament binds the epidural space posteriorly? Right Ans - The
ligamentum flavum
,At what level is the epidural space the widest? Right Ans - L2
At what level is the epidural space the narrowest? Right Ans - C5
Where does the dura mater extend from? Right Ans - The foramen magnum
to S2-3 vertebrae
Where does the arachnoid end? Right Ans - S2
What space lies between the arachnoid & pia mater? Right Ans - The
subarachnoid space
The epidural space is a potential space that is bound by the ____ & _____ ____.
Right Ans - dura
ligamentum flavum
Where is the blood supply to the SC & nerve roots derived from? Right Ans
- A single anterior spinal artery & paired posterior spinal arteries
Where is the principle site of action for neuraxial blockade? Right Ans - The
nerve root
Most important factors in determining distribution of LAs for spinal
anesthesia Right Ans - Density
Dosage & volume injected
Position of the patient during & immediately after injection..other factors are
height, spine, needle angle, site of injection, dose, vol, baracity density, sg
Uptake of LA is greatest where the concentration of the LA is the ______.
Right Ans - greatest
What determines the level of a block? Right Ans - Position
How do all subarachnoid blocks work? Right Ans - By diffusion down a
concentration gradient
What does the rate of elimination determine? Right Ans - The duration of
spinal anesthesia
,How are LAs eliminated? Right Ans - By vascular absorption via
subarachnoid & epidural blood vessels
The more the LA is bound to lipids, the less chance there is for ____ ____.
Right Ans - vascular absorption
What will decrease the rate of elimination of LAs? Right Ans - Decreases in
SC blood flow
Vasoconstriction
What is the predominant action of sympathetic blockade due to? Right Ans
- Venodilation
What does venodilation result in? Right Ans - Reduced venous return, SV,
CO, & BP
What can occur is sympathetic outflow from T1-T4 is blocked by a LA?
Right Ans - Unopposed vagal stimulation will produce bradycardia
(Bainbridge reflex)
What is bradycardia associated w/? Right Ans - Blockade of the
cardioaccelerator fibers & decreased venous return
What occurs w/ the decrease in venous return & corresponding reduction in
right atrial filling? Right Ans - The frequency of action potentials from
stretch receptors to the RA & great veins is diminished -> a reflex decrease in
HR
What is the best means for treating hypotension during spinal analgesia?
Right Ans - Give IV fluids if not normovolemic
Give ephedrine if normovolemic
Why should glucose solutions be avoided in the treatment of hypovolemia?
Right Ans - Glucose acts as a diuretic & can worsen the situation
(hypotension)
What is the best drug of choice for symptomatic bradycardia & why? Right
Ans - A mixed alpha & beta agonist (ephedrine)
, It increases the HR & peripheral vascular resistance
What occurs w/ a high block (C2-C3)? Right Ans - Phrenic nerve paralysis
& loss of accessory muscle of ventilation -> hypoxia
What ventilatory changes occur w/ a high spinal? Right Ans - Decreased
FRC d/t paralysis of abdominal muscles
Apnea (d/t hypoperfusion of the respiratory centers in the medulla 2˚ to
severe hypotension)
At what level of blockade do patients start to feel dyspneic? Right Ans - T2-
T4
What is the advantage of spinal over epidural anesthesia? Right Ans - The
ability to control the spread of the anesthetic by controlling the specific
gravity of the solution & the position of the patient.
How can trauma to the dura be minimized in the sitting position? Right Ans
- Using a pencil point needle (separates the dura)
If using a cut-bevel, needle will need to face either left/right to separate
(rather than tear) the dura
How can trauma to the dura be minimized in the lateral position? Right Ans
- Using a pencil point needle (separates the dura)
If using a cut-bevel needle, the needle must face up or down
How long should ticlodipine (ticlid) be stopped prior to neuraxial anesthesia?
Right Ans - 14 days
How long should clopidogrel (Plavix) be stopped prior to neuraxial
anesthesia? Right Ans - 7 days
How long should LMWH (enoxaparin [lovenox]) be delayed postop to
decrease the risk of a spinal hematoma? Right Ans - 24 hrs
If postop LMWH will be used, epidural catheters should be removed _____ ____
prior to the 1st dose. Right Ans - 2 hrs.
T7 dermatome Right Ans - Inferior border of scapula (lower tip)
