question

there are no absolute indications for spinal or epidural anesthesia. There are clinical situations where patient preference, physiology, or the surgical procedure makes a block the technique of choice. things epdiural anesthesia have been shown to do are?

answer

1. blunt the "stress response" to surgery 2. decrease intraoperative blood loss. 3. lower the incidence of postoperative thromboemolic events. 4. possibly decrease morbidity in high-risk patients. avoid airway manipulation. 5. serve as a useful method to extend analgesia into the postoperative period.

question

Pedicles, where is it

answer

there are 2 pedicles project posteriorly

question

Lamina, what does it bridge

answer

2 lamina that connect the pedicles together forming the vertebral canal

question

Spinal canal, what (3) things does it contain?

answer

vertebral canal contains the spinal cord, spinal nerves, and epidural space to the sides

question

Transverse Processes

answer

The laminae give rise to the TRANSVERSE PROCESSES, which project LATERALLY, and the SPINOUS PROCESS, which projects POSTERIORLY.

question

The spine consits of? #verabrae, cervical, thoracic, lumbar, sacrac, coccygeal?

answer

33 vertabrae 7 cervicle 12 thoracic 5 lumbar 5 fused sacral 5 fused coccygeal

question

cervical & lumbar convex?

answer

anteriorly (<

question

thoracic & sacral convex?

answer

Posteriorly >)

question

Supine: High points/ Low points?

answer

high points= C5 and L5 Low points = T5 and S2

question

the _____th sacral verebra is not fused giving rise to the sacral hiatus. what is this ?

answer

this opening into the sacral canal is the caudal termination of the epidural space

question

sacral cornu

answer

bony prominneces on either side of the hiatus, is a caudal landmark.

question

landmark, spinous process of C7

answer

most prominent, back of the neck

question

landmark, spinous process of T7

answer

inferior angle of the scapula

question

landmark, spinous process of T12

answer

12 rib attachement

question

landmark, spinous process of L5

answer

line between the iliac creasts crosses the L5 or L4-L5 interspace

question

how many pairs of spinal nerves?

answer

31 pairs of spinal nerves, each with a ventral and dorsal root

question

how many cervical, thoracic, lumbar, sacral, coccygeal nerves?

answer

8 cervical-----------------------PNS 12 throacic-----------Sympathetic 5 lumbar--------------Sympathetic 5 sacral---------------Sympathetic 1 coccygeal nerve------------PNS

question

cervical nerves transverse ___________ to corresponding vertebra

answer

cephalad (up)

question

Throacic and lumbar nerves traverse _________ to the vertabra

answer

caudad (down)

question

efferent motor fibers are located

answer

anteriror nerve roots of the anteriror and lateral horns of the spinal cord gray matter

question

afferent sensory fibers are located?

answer

dorsal nerve roots from the cell bodies inthe dorsal root ganglia

question

the cauda equina "horses tail" starts in the ______ for adults and ________ in neonates. what significance is this?

answer

L1= adults L3=neonates beyond these points is the termination of the spinal cord. would want to go in the L4-L5 spinal to avoid permanent damage.

question

dermatome is?

answer

a semental area of skin innervated by one spinal nerve root.

question

Dermatones significance: clavicle-c4 little finger-c6 nipple line-t4 umnbilicus-t10 popliteal fossa-s2

answer

-Clavicle= difficulty breathing -"little finger"= WARNING SIGN! all cardioaccelerator fibers are blocked T1-T4, may need to give ephidrine. -nipple line= some cardioaccelerator blockade -umbilicus= some sympathetics to LE -Popliteal fossa= pop fossa blocks

question

C3 dermatone

answer

difficutly breathing, they can still inervate the diaphram but they do not sensate breathing, putting hand on chest can help this.

question

dermatomes for surgery -upper addominal -intestinal, gyn, pelvice, and renal surgery -turp, vaginal delivery -knee, lower leg -foot surgery -hemorrhoidectomy

answer

- upper abd = T4-T5 Nipple -intestn....=T6-T8 (xiphoid) -turp.....= T10 (umbilicus) -knee = L1 (inquinal ligament) - foot = L2-L3 (knee and below) -hemorrhoi....... = S2-S5 (perineal)

question

most difficult nerve root to block?

answer

S1 outer side of foot, there is no lumbar sympathetic block

question

how many dorsal roots need to be interrupted to produce complete denervation of a dermatome?

answer

three (3)

question

Ligaments

answer

vertebral bodies are stabilized by several ligaments -supraspinous -interspinous -ligament flavum -longitudinal ligaments

question

supraspinous ligament, extends from _______ to ________. where is it thickest?

answer

strong fibrous cord, connects the spinous processes from the sacrum to C7. we know this is the lateral portion. it is thickest and broadest int he lumbar region

question

interspinous ligament. characteristics?

answer

is a think membrane, connecting the spinous processes as well. it is also thickest in the lumbar region

question

ligamentum flavum. characteristics, location

answer

"yellow ligament", connects adjacent laminae (the middle of the vertabrea, but not the spinous process it begins in the roots of the articular processes extending posteriorly/medially to where the laminae join to form the spinous process.

question

spinal ligaments (picture)

answer

supra,inter,flavum, then longtidunal is anterior

question

what insertion technique is least likely to result in accidnetal menigeal puncture? at what level is the ligamentum flavum the thickest?

answer

midliine insertion of an epidural needle. at L2-3 the ligamentum flavum is thickest in the midline (3-5mm) and farthest from the spinal memninges in the midline, which is what we want to aviod.

question

epidural space

answer

surrounds the spinal meninges, extends from the foramen magnum to the base of the skull to the sacral hiatus (S5) the epi space is composed of a series of dicontinous compartments, which become cointous when fluid or air is injected into them it is bound anteriorly by the posterior longitudinal ligament laterally by the pedicles and the intervertebral foramina posteriorly by the ligamentum flavum and the anteriror surgace of the lamina

question

where is the epidural space widest

answer

posteriorly and varies witht he verebral level. C5= 1-1.5mm T6= 2.5-3mm L2= 5-6mm (widest)

question

average distance to epidura space -adult -obese adult -thin adult

answer

adult= 4-6cm obese adult= up to 8cm thin adult= 3cm

question

contents of the epidural space

answer

nerve roots fat areolar tissue lymphatics arteries extensive venous plexus of batson, "valveless veins" this can be easily threaded into

question

Meninges

answer

the spinal cord is protected by both the bony vertebral column and the three connective tissue of the meninges. dura mater arachnoid mater pia mater

question

dura mater? / what space lies below this?

answer

the outermost membrane, and is a tough fibroelstic tube of fibers which run longtiudinally. below this is the "subdural" space drug intended for either the epidural space or subarachnoid space may be accidentally injected into this space, and this would be a failed block.

question

arachnoid mater? / what space lies below this?

answer

avascular membrane that serves as the principal physiologic barrier for drugs moving between the "epidural space and the subarachnoid space." puncturing this one runs into the subarachnoid space (spinal drug area). this space between the arachnoid mater and pia mater contains CSF. spinal nerve roots and rootlets run in the subarachnoid space, and it is continous to the brain ventricles.

question

pia mater

answer

delicate, highly vascular membrane that clings to the spinal cord and brain. BLOOD VESSELS supplying the spinal cord are in this space. aids in lateral support of spinal cord by laterally projecting denticulat lagaments to the dura

question

Spinal cord picture, ends at _______neonates and ________ in adults

answer

neonate= L3 Adults= L1 but extends to L3 in 10% of the population

question

CSF brain/spinal cord volumes? total volume made per day? where does most of it lie?

answer

is an ultrafiltrate of blood plasma Brain volume: 100-150ml Spinal volume: 25-35ml total of 350-500cc mader per day most lies in the cauda equina, below L1 in adults, L3 in children.

question

where is CSF formed

answer

choroid plexus of the lateral ventricles third vetricle (via foramen and monroe) fourth ventricle, aqueduct of sylvias brain and spinal cord via luska and foramen of magendie

question

where is CSF reabsorbed

answer

arachnoid villi

question

what big differences are there in the concentration of CSF and serum

answer

Protien: 28csf/7000serum both osmos are 289

question

spinal cord blood supply

answer

arterial blood -1 anterior spinal artery provides 75% of blood -2 posterior spinal arter provide ofther 25% of blood there are also 3 small segmental spinal arteries that are barely contributing

question

artery of adamkeiwicz

answer

is largest feeder artery to spinal cord, and supplies the anteriror spinal artery in the lumbar area, this would primaryly effect motor function if blocked.

question

spinal anesthesia

answer

the major cause of loss of sensation and muscle relaxation during spinal anestheis is the action of local anestheics on the spinal nerve root, dorsal root ganglia and spinal cord. SAB sub arachnoid block

question

zones of differential blockade related to spinal anesthesia

answer

SNS--->SENSORY----->MOTOR are blocked in that order. preganglionic sympathetic nervous system fibers (B-fibers) are located more proximally within the spinal nerve roots and the anesthetize first, then sensory (C-fibers) and finally motor fibers (A-delta and the A-gamma, A-beta, A-alpa)

question

why does the duration of action of ester local anesthetics as well as of amides placed in the subarachnoid space depen on vascular absorption of the drug?

answer

because csf does not contain significant amounts of cholinesterase enzymes.

question

the level of sympathetic nervous system block extends ________ spinal segments __________ to the level of sensory anestheisa and the levl of motor blcok averages ___________ segments _____ sensory anesthesia

answer

two cephalad (up) two segements belows

question

Baricity

answer

specific gravity of loval anesthetic relative to CSF, will influence spread.

question

hyperbaric solution

answer

heavier than csf, add glucose will increase specific gravity

question

isobaric solution

answer

same specific gravity as csf, dilut the LA solution with equal parts of csf

question

hypobaric solution

answer

add distilled water, lowers the specific gravity of the LA solution below that of csf

question

what should always be available during spinal anesthesia

answer

airway resuscitation equipment monitor: ekg, bp,sao2,oxygen via FM applied sterile glove>spinal tray>spinal drugs

question

epidural needles are typically __________gauge? spinal needles are typically ________ gauge?

answer

epi= 16-19 gauge spinal- 22-29 gauge

question

what is traversed from outside to inside while inserting a spinal needle using the midline technique

answer

skin> subQ tissue> supraspinous ligament> interspinous ligament> ligamentum flavum> epidural space> dura mater "pop"> subarachnoid space is entered until CSF is obtained.

question

spinal vs epidural dosing

answer

spinal probably 1-1.5cc of LA epidural: could be up to 10cc sometimes

question

epdiural anesthesia test does

answer

adminstered through the catheter to rule out catheter tip entry in the intravenous epidral veirn or intrathecal space (subdural,subarachnoid) before incrementally giving the entrie drug dose. -3ml of LA solution (1.5% lidocaine with 5mcg/ml of epinephrine. (1:200,000) -LA will produce evidence of spinal anesthesia with accidnetal intrathecal injection -Epi dose will increase heart rate 30bts/min, in <30 seconds lasting 30 seconds.

question

positive epidural test would be?

answer

increase heart rate 30bts/min, in <30 seconds lasting 30 seconds.

question

baricity and patient positioning with -Hyperbaric -hypobaric -isobaric

answer

-hyperbaric solution flow to dependent regioins of the spinal column -hypobaric solutions tend to float in the CSF -gravity has no effec on the distribution of isobaric solutions.

question

adrenergic agonists typically prolong duration of LA for lidocain and mepivacaine but have no effect on?

answer

bupivacaine and etidocaine

question

potency of local anesthetics is related to ?

answer

their lipid solubility

question

the duration of local anesthetic is affected by?

answer

the amount of protient binding

question

the onset of action of local anesthics is related to?

answer

the amount of local anesthic available in the base form

question

3 important factors in setting of sab/block height

answer

-braicity of LA -Postion of the patient during and just after adminstration of LA -Dose of anesthitic injected

question

order of blockade for spinal anesthesia

answer

autonmic> temperature>pain>touch>pressure>motor>vibration>proprioception>

question

what levels of the spinal cord constitute the diaphram drive

answer

C3,C4,C5 make and keeps the brain alive

question

sympathetic cardioaccelterator fibers are located?

answer

T1,T2,T3,T4 this also decreases sensativity to stretch receptors

question

Possible indication for spinal/epi

answer

-full stomach -anatomic distortions of upper airway -certain types of operations, pregnancy, turps sometimes (dilutional hyponatremia)

question

absolut contraindications to spinals/epi

answer

1.infections at the site of injection 2. dermatologic condition (psoriasis) 3. speticemia or baceremia 4. shock or severe hypovolmeia 5.preexisting disease involving the spinal cord 6. increased ICP 7. major abnormality of blood clotting mechanicsms 8.patient refusal, phychiatric unsuited 9.lack of skill in or experience with placing regional blocks 10. the surgeo cannot predicatably perform operation in time. 11. uncertainty about the duration of the operation, "ex-lap or whipple"

question

would you perform spinal on someone with aortic stenosis

answer

probably not, this is a relative contraindication based on cardiac diseass, that if sensory levels of T6 or above were affected there could be issues.

question

complications of spinal/epi?

answer

1. backache 11% spinal 30% epidurals 2.post dural punctur headache (up to 50% of patient after menigeal puncure by epidural) 3.systemic toxicity 4.epdiral hematoma, (late complication) 5.infection/abcess 6. total spinal (coughing can raise level of spinal)

question

coughing can do what when adminstering a spinal?

answer

it can actually raise the level of LA and block

question

total spinal

answer

Hypotension - treat as detailed above, volume, pressors. Remember that nausea may be the first sign of hypotension. Repeated doses of vasopressors and large volumes of fluid may be necessary. Bradycardia - give atropine. If this is not effective give ephedrine or epinephrine. Increasing anxiety - reassure. Numbness or weakness of the arms and hands, indicating that the block has reached the cervico-thoracic junction. Difficulty breathing - as the intercostal nerves are blocked the patient may state that they can't take a deep breath. As the phrenic nerves (C3,4,5) which supply the diaphragm become blocked, the patient will initially be unable to talk louder than a whisper and will then stop breathing.

question

treatment of post subdural headache

answer

Treatment Supine Fluids Analgesic/caffeine Epidural blood patch

question

spinal advantages

answer

Less time/skill/equipment to perform More rapid onset Better quality/denser sensory and motor block Less pain during surgery

question

epidural advantages

answer

Less risk of PDPH Less hypotension if no epi added Can prolong/ extend block via an indwelling catheter Epidural catheters aid with post-op pain Epidural often used to supplement general anesthesia for large abdominal surgeries

question

indication for caudal block

answer

Surgery below the umbilicus Hernia repair Lower limb surgery Skin grafting GU procedures Procedures on the anus and rectum Orthopedic surgery on the pelvic girdle Pediatric GU/hernia surgery

spinal and epidural anesthesia – Flashcards

Unlock all answers in this set

Haven't found what you were looking for?

Search for samples, answers to your questions and flashcards