spinal Flashcards
How many cervical spine
7
How many thoracic spine
12
where are cardioaccelerators
T1-4 or 5 per PP
s/s cardio accelerators
s/s of a high spinal
hypotension
bradycardia
How many lumbar spine
5
connus medullaris
the tapered end of the spinal cord, which is usually located near the first or second lumbar vertebrae in the back of an adult???
L1 adults
L3 in children
5-6mm deep
Tuffiers Line
Body of L4/L5 or the 4-5 interspace.
where does spinal cord begin?
foramen magnum base of skull
large, oval-shaped opening in the occipital bone at the base of the skull that allows the central nervous system to pass through and connect the brain to the spinal cord.
Where does spinal cord end in adults
L1
Where does spinal cord end in cihldren
L3
How many sacral spine
5 fused
How deep is epidural space in Lumbar spine?
5-6mm deep
The sacral hiatus
provides an opening into the sacral canal which is the caudal termination of the epidural space
Anterior spinal artery
supplies 2/3 of anterior cord
Artery of Adamkiewicz (arteria radicularis magna)
originates from vertebral artery
terminates along the anterior surface of the cord
why does aortic clamping cause ischemia?
stops blood flow to artery of adamkiewics?Paresthesia, paralysis, incontinence.
Two paired posterior spinal artery
supply posterior 1/3
originates from vertebral artery
terminates along the anterior surface of the cord
Name Skin to CSF layers
skin
subcutaneous tissue
supraspinous ligament
interspinous ligament
ligamentum flavum “pop” then stop for epidural
epidural space
dura mater (subtle pop or click)
arachnoid mater
subarachnoid space CSF
whats layers are deep to the epidural space
Dura Mater
Arachnoid
Subarachnoid space (CSF= Spinal)
Pia Mater: On the cord
these are continuous with cranial meninges
neuraxial blocks decrease incidence of
- Cardiac complications
- Bleeding
- DVT/Pulmonary embolism
- Pneumonia
- Respiratory depression
- Decreased vascular graft occlusion
- Increased peristalsis
- Blunt stress response in CAD patients
- Decreases opioid use
Absolute contraindications to neuraxial
Patient refusal
Relative Contraindications
Sepsis
Uncooperative
Preexisting neurological deficits
Coagulopathy / Bleeding diathesis
Severe hypovolemia
Increased ICP
Severe aortic or mitral stenosis
Prior back surgery
Inability to communicate with patient
Complicated surgery
Prolonged operation
Major blood loss
Maneuvers that compromise respiration
Demyelinating lesions seen on cord with MS, Guillain Barre, CIDP Chronic inflammatory demyelinating polyradiculoneuropathy.
what is isobaric
1.004-1.009
hyperbaric solution
Glucose
>1.009
drops to dependent area
hypobaric solution
<1.004
sterile water
rises
spinal epi wash mg
0.1-0.2mg of 1:1000 solution
draw up and squirt out
increases duration of spinal
Paramedical approach.. what is the first ligament
ligamentum flavum
What needle is more likely to cause PDPH?
quincke
but improve tactile sensation
Cause more trauma than pencil point.
Cut through dura instead of spread fibers
Increased risk of headaches
what decreased PDPH
Pencil point (whitachre and sprottle)
small needles
Spread neural fibers versus cutting them
most common site for spinal block
L3-L4
where is the largest interspace
L5-S1
Bupivacaine 7.5 mg per ml
15 mg = 2 cc spinal
12 mg = 1.75 cc spinal
+ epi = prolong = vasoconstrict
prep for SAB
Sterile procedure
GIve IV fluid bolus of 500 cc prior to SAB and epidural dose
If it’s not labor epidural or c/s, give versed, fentanyl, and oxygen prior to neuraxial anesthesia
LA to the skin, deep tissues
IV, O2, ECG, BP, emergency airway, drugs, hat, mask, gloves, glown, spinal kit with local top be used.
midline approach
Localize the skin
Needle should be directed slightly cephalad 30°
Needle will pass through three ligaments
Supraspinous
Interspinous
Ligamentum flavum
Dura mater (thecal sac)
Feel for “small pop”
CSF flows thru once stylet is removed
conduction block
B: slow
C: pain/temp/sympathetic
A small: pain/temp
A large: motor, proprioception
Sympathetic block
2-6 dermatomes higher than the sensory block
depress secretion
decrease the tone and contractility of smooth muscle
increase heart rate
Motor block
2 dermatomes below
large diameter
myelinated sensory and motor
Progression of Spinal Blockade
S- sympathetic
T-temperature
P- pain
T- touch
P-pressure
M-motor
V-vibratory
P-proprioception
Some times penny tries pressing me very politely
If bone (os) encountered superficially
redirect needle cephalad
hallmark sign of PDPH
NO HEADACHE WHEN LYING SUPINE
If bone (os) encountered deep
redirect needle caudally
Complications of neuraxial blocks
Immediate complaint of nausea
Hypotension
PHENYLEPHRINE
Get bp up
Epidural blood patch
10-15 ml autologous blood is injected att he site of the meningeal tear
Seals dural rent by forming a thrombus
1st patch 60-90% effective
Second 98% effective
Introducer needle fluid leaking back
Might be lidocaine leaking back → you probably won’t reach the CSF with the introducer
Cauda Equina syndrome characterized by
1 perineal sensory deficits
2 urinary and fecal incontinence
3 varying degrees of lower extremity motor deficits
on your way to total/high spinal
Bradycardia
Hypotension
Weak cough
Drop in O2
treat a high spinal
anticholinergics
Phenylephrine
Fluids
ephedrine
respiratory support
reverse trendelenburg
factors influencing high spinal
1 Local dose
2 Patient position especially if a hyperbaric solution is used.
3 Height
4 Age ???? old or young
5 Gender
6 Intra Abdominal pressure: compression: 7 Obese/ Obstetric
8 Anatomic configuration of SC
when to check level of spinal after block
4 min
spinal block progression
1 temp
2 pinprick
3 light touch
why does total/high spinal cause hypotension?
Due to venous/arteriolar vasodilation
decreased CO
decreased SVR
why does total/high spinal cause bradycardia?
Widespread sympathetic blockade leading to unopposed vagal (parasympathetic) tone and blockade of T1-T4- the cardioaccelerator fibers.
Also may be due to decreased right atrial filling
Treatment involves anticholinergic Rx (atropine) or B1 agonists, i.e. ephedrine
respiratory failure with high spinal
Paralysis of intercostals leading to decreased chest wall sensation
If blockade reaches C3-C5, diaphragmatic innervation lost with rapid, progressive respiratory failure
Early warning signs:
1 poor resp effort, whispering and inability to cough
Acute respiratory arrest is due to hypoperfusion of the brainstem
Treatment depends on severity:
O2, BVM vent, and most likely intubation
an early sign of high spinal
progressive dyspnea
weak hand grip
can’t touch nose
ineffective cough
hypotension
bradycardia
RR 12-15
SpO2 <95%
function diminished
