1. Types of local anasthetic
Name: nur A’isyah binti idris
Serial no.: 61
2. INTRODUCTION
• The local anaesthesia is designated according
to the technique or anatomical site where it is
injected or applied
• It allows patients to undergo surgical and
dental procedures with reduced pain and
distress.
3. Types of local anasthetic
Surface
anaesthesia
Infitration
anaesthesia
Conduction
block
anaesthesia
Central nerve
block
anaesthesia
Intravenous
regional
anaesthesia
4. Surface anaesthesia
• Topical application to
mucous membrane &
abraded skin.
• Do not work well on
intact skin.
• The sensory nerve
endings are the chief
nerve affected.
• Only superficial layer is
anaesthetised.
• Form: solution, oitments,
cream , sprayed
• Drug Used:
• Tetracaine (2%)
• Lidocaine(2-5%)
• Eutectic mixture (5%)
• Benzocaine(5%)
• Dyclonine(0.5-1%)
• Promaxine(1%)
5. Uses:
• to facilitate endoscopic
procedures
• to reduce pain of
hemorroids/ anal
sphincter.
• On eyes:
For tonometry, surgery
To remove foreign
bodies from corneal &
conjunctiva
For preoperative
preparation.
• Others:
• Nasal lesion
• Tonsilectomy
• Burns
• Protoscopy
• Stomatitis
• Sore throat
Surface anaesthesia
6.
7. Infitration anaesthesia
• Dilute solution of LA
produced by injection of
the anesthetic solution in
the area of sensory nerve
endings
• Aims: to block sensory
nerve terminals.
• Onset of action: immediate
• Duration of action: shorter
than nerve block
• Adrenaline / felypressin
added to retard absorption
• Uses:
minor surgical
procedures ( incision &
excision)
Hydrocele
Herniation
8. Advantages
• Possible to provide
anesthesia without
disruption of normal
body function
Disadvantage
• In major surgeries-
systemic toxicity
Drugs used:
• Lidocaine (1%)
• Bupivacaine(0.25%)
• Etidocaine(0.5-1%)
• Ropivacaine(0.5-1%)
• Mepivacaine(1-3%)
• Prilocaine(1-4%)
Infitration anaesthesia
9. Conduction block anaesthesia
• Injected around the nerve
trunk, so the area distal to site
of injection is anaesthetised &
paralysed.
Field block
• Injected sc
• All other nerve coming to a
particular field are blocked
Uses:
• Applied to scalp & ant.
abdominal walls where nerve
travel superficially to supply
the area.
• Advantage: small dose of
drug provided for larger area
• Drugs used: Lidocaine
Bupivacaine, Ropivacaine
Mepivacaine, prilocaine
Nerve block
• Injected around appropriate
nerve trunks or plexuses.
• Provide large area of
anaesthesia .
• Muscle supplied by injected
nerve/ plexus are paralysed.
10. • Duration depends on lipid
solubility & protein
binding
• Frequently performed
nerve block:
Lingual
Intercostal
Ulnar
Sciatic
Femoral
Brachial plexus
Trigeminal
Facial
Inferior alveolar
• Uses:
Tooth extraction
Operation on eye, limb ,
abd. Wall
Fracture setting
Trauma to ribs
neuralgias
• For block of 2 to 4 hr,
intermediate acting like
LAs like lidocaine or
mepivacaine can be used.
• Longer duration -
bupivacaine
Conduction block anaesthesia
11. Central nerve block anaesthesia
• Includes: epidural & spinal
block
A)Epidural block anaesthesia
• LA is injected in the dural
space which is filled with
semiliquid fat through
which nerve is travel.
• Acts on nerve roots & small
amount of permeates
• Aims: to produce multiple
paravertebral blocks.
• Drug used: Lidocaine,
Bupivacaine , Ropivacaine
• 3 categories depends on site
of injection:
Thoracic
• Injection in midthoracic
region
• Epidural space narrow : small
volume of drugs is needed
• Wide segmented band of
analgesia is produced
• uses: pain reliever – upper
abd. surgery
12. Central nerve block anaesthesia
Lumbar
• Epidural space wide :
large volume of drug
needed
• Produce anaesthesia of
L. abdomen, pelvis &
hinds limbs
• Uses: similar to spinal
anaesthesia
Caudal
• Injection in sacral canal
through sacral hiatus
• Produce anaesthesia of
pelvic & perineal
region
• Uses: vaginal delivery,
anorectal, genitourinary
operations.
13.
14. Central nerve block anaesthesia
• B) Spinal block anaesthesia
• Injected LA in the spinal
subarachnoid space
between L2 and L3, or L3
and L4
• Primary site of action is the
nerve roots in cauda
equina rather than spinal
cord.
• Drug used: lidocaine,
tetracaine, Bupivacaine
• Advantages
• Safe, affords good analgesia
, muscle relaxation & no
loss of consciousness
• Preferred to be used in
cardiac, pulmonary & renal
disease
• Uses:
• Surgical procedure on L.
limb, pelvis, L. Abdomen,
obstetrics & C-section
procedures.
16. Intravenous regional anaesthesia
• Also reffered to Bier’s
block
• Useful for rapid
anaesthetization of an
extremety.
• Uses: For the upper limb
and for orthopaedic
procedures
Drug used:
• Lidocaine
• Prilocaine also preffered
because of its higher
safety index.
• Bupivacaine is avoided
because of its higher
cardiac toxicity.
17. Procedure :
1. The limb first is elevated
to ensure venous drainage
and then tightly wrapped
by an elastic bandage for
maximal exsanguination.
2. Tourniquet then applied
proximally and inflated
just above systolic BP.
3. Then elastic bandage
removed, lidocaine is
injected IV.
• Normally the cuff is
inflated for at least 20min
to minimise systemic
toxicity.
18. Adverse effects
• CNS :
• low dose: tongue numbness, sleepiness, mild
headache, visual & auditory disturbances
• High dose: nystagmus, muscular twitching
• CVS : depress abnormal cardiac pacemaker activity
• Blood : large dose of prilocaine accumulation of
metabolite orthotoluidine oxidised HB to methHB
cyanosis
• Allergic reaction: ester LA metabolised to PABA
derivative.
19. Conclusion
• There are 5 types of LA.
Surface
anaesthesia
Infitration
anaesthesia
Conduction
block
anaesthesia
Central nerve
block
anaesthesia
Intravenous
regional
anaesthesia