Exam 1 Spinal & Epidural Neuraxial Anesthesia [5/28/24] Flashcards
What cannot be given through the spinal?
Reglan and Zofran `
3
What are the clinical Indications for neuraxial anesthesia?
- Surgical procedures involving the lower abdomen, perineum, and lower extremities
- Orthopaedic surgery [alot of spinals]
- Vascular surgery on the legs
- Thoracic surgery (adjunct to GETA) [usually epidurals]
VOTS
S5
What are the 6 benefits for neuraxial anesthesia?
Reduces the following:
1. Postoperative ileus
2. thromboembolic events
3. Respiratory Complications
4. PONV
5. Narcotic Usage
6. Bleeding
I Take Rare Ponies, Not Babies
S6
List the other benefits of neuraxial anesthesia.
- Great mental alertness
- Less urinary retention*
- Quicker to eat, void, and ambulate
- Avoid unexpected overnight admission from complications of general anesthesia
- Quicker PACU discharge times*
- Preemptive anesthesia
- Blunts stress response from surgery
BM QUAP
S7
If using neuraxial anesthesia, and the pt needs to be put to sleep but needs to maintain respiratory drive what can be administered?
- Propofol
- 100-300 mcg/kg
S7
What are the relative contraindication for neuroaxial anesthesia
- Deformities of spinal column [issues w/positioning]
- Preexisting disease of the spinal cord [residual weakness]
- Multiple Sclerosis, post polio syndrome
- Chronic headache/backache
- Inability to perform SAB/Epidural after 3 attempts
S8
Why are chronic headaches/backaches a relative CI for neuroaxial anesthesia?
- A complication of neuroaxial anesthesia is post-dural puncture heacache.
- if pt has backpain, and we are sticking needes in the back it might worsen the pain
S8
What are the absolute CI for neuroaxial anesthesia?
- Coagulopathy
- Patient refusal
- Evidence of dermal site infection
- known coag disoder or on anticoagulants
- Severe or critical valcular heart disease
- HSS [idiopathic hypertrophic subaortic stenosis]
- Operation >duration of LA
- Increased ICP
- Severe CHF
Contraindicated Patients Don’t Seem Happy Or Invincible Systematically
S9-10
What are the coagulation problems that are absolute contraindications for neuroaxial anesthesia
- INR > 1.5
- PLT < 100,000*
- PT, PTT, BT x 2
List the factors involved in the coagulation cascade
* Intrinsic
* Extrinsic
* Common
- Intrinsic: 12, 11, 9, 8
- Extrinsic: 3, 7
- Common: 10, 5, 1, 2,13
S9
PT/INR measures?
PTT measures?
- PT/INR = extrinsic
- PTT = intrinsic
S9
PT = PLAY TENNIS OUTSIDE = EXTRINSIC
PTT = PLAY TABLE TENNIS INSIDE = INTRINSIC
What does the bleeding time look at?
- Examines PLT activation and adhesion.
- longer BT = problem with PLTs.
S9
What severe valvular heart diseases are absolute CI for neuroaxia anesthesia?
- Aortic stenosis <1cm2
- Mitral stenosis <1cm2
S10
List the valve area for AS for the following:
* Mild
* Moderate
* Severe
* Critical
- Mild: >1.5 [greater than or equal to]
- Moderate: 1.0 - 1.5
- Severe: 0.7 - 1.0
- Critical: < 0.7
cm2
What is the average course of valvular aortic stenosis in adults
- Age 35-40: increasing obstuction, myocardial overload
- Age 60: onset of severe symptoms **
- Age 63: average age of death.
S10
What are the s/sx of severe or critical AS? What are its survival rates?
- Angina - 5yrs
- Syncope - 3yrs
- Heart failure - 2 yrs, the worst [NYHF 3 or 4]
S10
What is the death spiral that occurs due to AS?
- hypotension causes myocardial ischemia
- ischemia contractile dysfunction
- decreases CO
- worsening hypotension
- increased ischemia
S10
Compare & Contrast the following characteristics of spinals and epidural:
* Onset
* Spread
* Nature of block
* Motor block
* Hypotension
S11
Compare & Contrast the following characteristics of spinals and epidural:
* Onset
* Duration
* Placement level
* Difficulty of placement
* Dosing
* Concentration
* LA toxicity
* Gravity influence
* Manipulation of dermatome spread after dosing
S10
What is the placement and needle size for spinals?
- Placement:L4-L5
- Smaller needle: 25-27g
S12
What is the placement and needle size for epidurals?
- Placement: anywhere there is epidural space
- bigger needle: 18-19 g
- can do epidurals by thoracic but draw back is accidentally hitting the spinal cord.
S12
Positioning affects epidurals or spinals?
How would you postion a pt with right hip pain?
- Affects epidurals
- pain in right buttock - turn to right side to have LA stay on that side.
S12
How many total vertebras do we have?
* Total:
* Cervicle:
* Thoracic:
* Lumbar:
* Sacrum:
* Coccyxs:
- Total: 33
- Cervicle: 7
- Thoracic: 12
- Lumbar: 5
- Sacrum: 5
- Coccyx: 4
S14
What are the 4 curvatures of the spine?
- Normal
- Scoliosis
- Kyphosis
- Lordosis
S14
Each vertebra, except for ____, is divided into two main parts:
* The____ segment, known as the body.
* The ____ segment, called the vertebral arch.
- C1
- anterior
- posterior
slide 15
what 2 structures link the anterior and posterior segments?
the lamina and pedicle
slide 15
The vertebral foramen is a crucicial space within the verbra why?
houses the spinal cord, nerve roots, and the epidural space, which is a protective cushioning area around the spinal cord.
slide 15
The ____ processes stick out to the sides (lateral), while the ____ processes stick out towards the back (posterior).
- transverse
- spinous
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what attach to the spinous and transverse processes to help stabilize and support the spine?
muscles
slide 16
Cervical and thoracic spinous processes tilt ____, requiring a needle approach from ____.
- downward (caudal direction)
- above (cephalad approach)
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Lumbar spinous processes stick out directly ____, which makes it easier to reach the spaces around the spinal cord, such as the ____ & ____ spaces.
- backwards (posterior)
- epidural and intrathecal spaces.
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These are the soft pads between each vertebra that act as shock absorbers.
intervertebral disc
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These are the openings between the vertebrae where spinal nerves exit the spine.
intervertebral foramina
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whati s the function of the facet joints?
They help guide and limit the spine’s movement, keeping the back’s motions controlled.
slide 19
surface landmarks
where is the superior aspect of the iliac crest?
L4
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where is the posterior superior iliac spine?
S2
slide 20
what is tuffier’s line [intercristal line]?
This horizontal line runs across the top edges of the hip bones (iliac crests) and matches the L4 vertebra
slide 20
Tuffier’s Line helps identify the correct spaces between vertebrae for inserting spinal anesthesia needels.
* The space above this line aligns with the ____ vertebrae.
* The space below this line aligns with the ____ vertebrae.
- L3 - L4
- L4-L5
slide 20
in infants up to one year the intercristal line corresponds with the ____ intervertebral space
L5-S1
slide 20
The sacrum is a triangular-shape section of fused vertebra (5). The lamina of ____ is incomplete and bridged only by ligaments.
S5
slide 22
Sacral Hiatus
* location?
* covered by?
* purpose?
- Located at the base of the sacrum and aligns with the S5 vertebra.
- Covered by the sacrococcygeal ligament.
- Acts as an access point to caudal anesthesia
slide 22
Sacral Cornua
* The projections of the articular processes are known as cornu
* The sacral cornu are the “horns” or bony protuberances that guard the area of the ____
* Landmark for ____ anesthesia
- sacral hiatus
- caudal
slide 22
Components of the spinal cord?
- starts at the medulla oblongata
- conus medullaris
- caurda equina
- dural sac
- filum terminale
slide 23/24
the spinal cord has a ____ origin, starting in the ____.
- rostral origin
- medulla oblongata
slide 24
- What is the conus medullaris?
- where does it end in adults?
- where does it end in infants?
- where the spinal cord tapers off at the end
- In adults, it ends between the L1 and L2 vertebrae. (L1 in most textbooks)
- In infants, it ends at L3.
slide 23
- what is the cauda equina?
- what does it consist of?
- A bundle of spinal nerves extending from conus medullaris to the dural sac.
- Consists of nerve roots from L2 to S5 vertebrae and the coccygeal nerve.
slide 23
- Dural sac:
- where does it end in adults?
- where does it end in infants?
- Ends at S2 in adults.
- Ends at S3 in infants.
slide 24
- The filum terminale is a continuation of the ___?
- It extends from the ___ to the ___.
- what is its main function?
- It is a continuation of the pia mater.
- It extends from the conus medullaris to the tailbone (coccyx).
- Its main function is to anchor the spinal cord to the coccyx.
slide 24
Describe the internal filum terminale:
- Begins at the conus medullaris, extending to the dural sac.
- L1-S2
slide 24
Describe the External Filum terminale:
- Starts from the dural sac and extends into the sacrum.
- S2-S5
how does the spinal cord receive blood supply?
- one anterior spinal artery
- two posterior spinal arteries
slide 25
Anterior spinal artery
* origination?
* supplies what part of the cord?
* how much does it supply?
- Originates from the vertebral artery.
- Supplies the front (motor) portion of the spinal cord.
- Supplies the anterior 2/3 of the spinal cord
slide 25
Two posterior spinal arteries
* Emerge from the ____.
* Originates from the ____ artery.
* Supply the ____ portion of the spinal cord.
- cranial vault
- vertebral
- posterior (sensory
slide 25
what part of the cord has better protection from ischemia the posterior or anterior?
- The posterior spinal arteries are paired and have many connections from the subclavian and intercostal arteries.
- These connections help protect the sensory part of the spinal cord from ischemia.
slide 25
what are symptoms of anterior spinal artery syndrome?
- Motor paralysis.
- Loss of pain and temperature sensation below the affected area.
slide 26
what are causes of ischemia that can lead to anterior spinal artery syndrome?
- Low blood pressure (profound hypotension).
- Mechanical blockage.
- Blood vessel disease (vasculopathy).
- Bleeding (hemorrhage).
slide 26
the anterior spinal artery receives additional blood slupply through what branches?
the intercostal and iliac arteries, though these are variable.
slide 26
Artery of Adamkiewicz:
* what is it?
* where does it arise?
* damage to this can cause what?
- A crucial connection that supplies blood to the lower two-thirds of the spinal cord.
- It usually arises from the aorta between the T9and L2 regions
- Damage to this artery can also lead to anterior spinal artery syndrome.
slide 26
what are the spinous ligaments posterior to anterior?
- Supraspinous Ligament
- Interspinous Ligament
- Ligamentum Flavum
- Posterior Longitudinal Ligament
- Anterior Longitudinal Ligament
slide 27
Runs along the back, connecting the tips of the spinous processes from the upper back down to the lower back.
Supraspinous Ligament
slide 27
Located between the spinous processes, providing stability by joining adjacent vertebrae.
interspinous ligament
slide 27
- They are particularly thick in the lower back and form the sidewalls of the space outside the spinal cord (epidural space).
- Piercing this ligament indicates entry into the epidural space during procedures.
ligamentum flavum
slide 27
Runs along the back side of the vertebral bodies inside the spinal column.
posterior longitudinal ligament
slide 27
- Attached to the front of the vertebral bodies, running the length of the spinal column.
- Also connects to the outer fibers of the intervertebral discs, helping to bind the vertebrae together.
anterior longitudinal ligament
slide 27
what layers are traversed during a midline spinal?
- Skin
- Subcutaneous fat
- Supraspinous ligament
- Interspinous ligament
- Ligamentum flavum
- Dura Mater (POP)
- Subdural space
- Arachnoid Mater
- Subarachnoid space
slide 28
Silly Stupid SRNA, I Like Doing Spinal Anesthesia Swiftly
what layers are transvered during a paramedian approach?
- Skin
- Subcutaneous fat
- Ligamentum flavum
- Dura Mater
- Subdural space
- Arachnoid Mater
- Subarachnoid space
slide 28
Stupid SRNA’s Like Doing Spinal Anesthesia Supine
Why might we decide to use a paramedian approach?
What about patient Positioning?
- Use: When the interspinous ligament is calcified or the patient cannot flex their spine.
- Positioning: Can be performed while the patient is sitting, lying on their side, or face down.
slide 28
Paramedian Approach Procedure:
- Insert the needle 15 degrees off the spine’s midline.
- Position the needle 1 cm to the side (lateral) and 1 cm below (inferior) the space between the vertebrae (interspace).
slide 28