SPINAL AND EPIDURAL ANAESTHESIA Flashcards
Spinal anesthesia/_______________ :
the injection of small amounts of LAs into the (______) at the level ____________ ,where the ________________ , anaesthesia of the _____________ part below the __________ is achieved
Subarachnoid block
CSF; below (L1)
spinal cord ends
lower body; umbilicus
SAB produces (few or many?) adverse effects on the respiratory system as long as ________________ are avoided.
Few
unduly high blocks
The costs associated with SAB are (minimal or maximal?) .
Minimal
In SAB, As ________________ is not compromised, there is a reduced risk of airway obstruction or the aspiration of gastric contents.
control of the airway
SAB provides _______ muscle relaxation for __________ and __________ surgery.
excellent
lower abdominal and lower limb
With SAB, Blood loss during operation is (more or less ?)than when the same operation is done under general anaesthesia.
Less
Splanchnic blood flow.
Because of its effect on ____easing blood flow to the gut, spinal anaesthesia reduces the incidence of ________________.
incr
anastomotic dehiscence
Visceral tone. The bowel is ________ by SAB and sphincters ______ although ________ continues. Normal gut function rapidly returns following surgery.
contracted ; relaxed; peristalsis
Coagulation.
Post-operative deep vein thrombosis and pulmonary emboli are (more or less?) common following spinal anaesthesia.
Less
Indications for SAB
Operations below the ______________ : hernia repairs, gynaecological and urological operations
Any operation in the _________ or __________
umbilicus
perineum or genitalia
Indications for SAB
All operations on the _____ except for _____________ which is possible but an unpleasant experience for an awake px so here the px is anaesthetized with _______ and sedation with _____
leg
limb amputation
SAB
GA
Indications of SAB
Special indications
________
_______________ dx hepatic, renal and endocrine dx ( DM )
Most patients with ________ diseases except for ______________ dxs and _______________.
Elderly
Chronic systemic
mild cardiac
stenotic valvular
uncontrolled HTN.
Contra-indications
Patient _________
_____________ patients: like young children and psychiatric or mentally handicapped pxs
________ diseases : as bleeding from ________________ is common , pxs with low platelet count or those on anticoagulant drugs (heparin + warfarin ) are at high risk of __________ formation.
refusal
Uncooperative
Clotting; ruptured peridural vein
hematoma
Contra-indications for SAB
Hypovolaemia: As SAB has marked _____tensive effects, hypovolaemic patients must be adequately __________ and __________
Septicemia: leading to __________ and ________
hypo; rehydrated and resuscitated
CSF infection and meningitis
Contra-indications for SAB
_____________ (relative contraindication)
as it will probably only serve to make the dural puncture more difficult.
Anatomical deformities
Contra-indications for SAB
______________ disease. Any worsening of the dx postoperatively may be blamed erroneously on the SAB.
Inadequate ____________ and ______________
Neurological
resuscitative drugs and equipment for GA
No regional anaesthetic technique should be attempted if ___________________________________ are not immediately available
drugs and equipment for resuscitation and GA
Local anaesthetics for SAB
LA agents are either ______ ,_______, or __________
hyper- ,hypo- or isobaric.
Hyperbaric agents tend to spread (above or below?) the level of injection and they are _____________, that’s why they are preferred over iso- and hypobaric agents.
Below
easier to predict
Local anesthetics for SAB
Bupivacaine ( ___________ ): ____% _______________________ is the best
____% _____________________ is also popular
Marcaine; 0.5
hyperbaric bupivacaine
0.5; isobaric bupivacaine
Local anaesthetic for SAB (Lidocaine)
Lidocaine ([___________): ___% _____baric lidocaine lasts ____________
——% lidocaine can be used but as a much (shorter or longer ?)duration of action
0.2mls of ————- 1:1000 + lidocaine will _______ the duration of action
Xylocaine; 5; hyper
45-90 mins
2; shorter; adrenaline; prolong
Lidocaine from ( multi dose vials ) should not be used ___________ally as they contain ___________________________.
intrathecally
potentially harmful preservatives
Factors affecting the spread of local anaesthetic solutions in CSF
The ________ of the local anesthetic solution The _________ of the patient
The _________ of injection
The _________ of injection
baricity
position
level
speed
Factors affecting the spread of local anaesthetic solutions in CSF
Obesity: as increase in ____________ decreases the ________________ , so doses must be ________
Pregnancy: increase in ____________ leading to increase in ______________ leading to less _________________ and _____ doses.
intra-abdominal pressure
subarachnoid space; reduced
intra-abdominal pressure; peridural veins filling
subarachnoid space; less
How to perform the spinal injection
It is a ________ procedure!
_______ the patient’s back with ________
Locate a suitable _____________________
Raise an ____________________ at proposed puncture site
Insert the needle
When ——— appears then slowly inject the local anaesthetic
sterile; Clean; antiseptic
inter-spinous space
intradermal wheal of LA agent
CSF
Spinal anaesthesia
Insert the needle: the structures that
will be passed:
List them all!!
skin,
subcutaneous tissue, supraspinous ligament, interspinous ligament, ligamentum flavum, dura mater
Complications of spinal anaesthesia
______tension: due to vaso_______ and a functional _____ease in the effective circulating volume.
___________ (PDPH): within ______ and may last for __________
Hypo; dilatation; decrease
Headache
12-24hrs; 1 week
Fix for hypotension in spinal anesthesia
By giving ———- and oxygen mask
_______ the ______: simple and effective
Increase the _______ of IV infusion: until the blood pressure is restored
Vaso____________ – _________ , ________
With concomitant ______cardia, give ________
fluids ;Raising ; legs
speed; Vasoconstrictor
phenylephrine ; ephedrine
bradycardia ; atropine
Fix for Headache (PDPH) in Spinal Anaesthesia
Occurs following use of ___________ needles and ______ gauge spinal needles
It is __________ and it is often ________ associated with a _____________, nausea, vomiting, dizziness and photophobia
Ask to ___________ and give simple analgesics
Quincke spinal
wide; postural
occipital; stiff neck
lying flat in bed
Complications of SAB
Urinary ____________ : the ____________ fibers are among the last to recover.
__________ complications (rare): meningitis, arachnoiditis, peridural abscess
__________________ : from direct injury of the spinal cord
retention ; sacral autonomic
Neurological; Permanent paralysis
Epidural Anaesthesia
Local anaesthetic solutions are deposited in the _______ space between the __________ and the _____________ lining the vertebral canal. The injected local anaesthetic solution produces ___________ by ————— at the _____________ nerve roots
peridural
dura mater; periosteum
analgesia
blocking conduction
intradural spinal
Epidural Anaesthesia
Technique:
________________ technique to identify the epidural space.
Loss of resistance
Epidural Anaesthesia
______ % ______ ———— (mainly) or ———— (——-%) is usually used to produce epidural anaesthesia
0.5% plain Bupivacaine
lidocaine (2.0%)
Epidural Anaesthesia contd.
Indications and Contraindications:
Same as spinal anaesthesia.
Additional indication is the __________________ using the epidural catheter technique
post operative pain management
Epidural Anaesthesia
Complications: the same of spinal anaesthesia, except the ____________________.
post dural puncture headache
Differences between Spinal and Epidural Anesthesia
Lebel
Injection
Hypotension
below L1/L2, where the spinal cord ends
at any level of the vertebral column.
subarachnoid space i.e. puncture of the dura mater
epidural space (between ligamentum flavum and dura mater) i.e without puncture of the dura mater
Rapid ; slow
Differences between Spinal and Epidural Anesthesia
Identification of the subarachnoid space
Headache
Density of block
When CSF appears( Using the loss of resistance technique.
Probable complication; not probable
More dense; less dense
Differences between Spinal and Epidural Anesthesia
Doses
Onset of action
Doses: 2.5- 3.5 ml bupivacaine 0.5% heavy
Doses: 15- 20 ml bupivacaine 0.5% plain
Onset of action: rapid (2-5 min)
Onset of action: slow (15-20 min)
