1. Regional anaesthesia Dr.Arkan Jaafar , M.D. Anesthesiologist
Medical college of Mosul

2. Regional anaesthesia is ideal for many operations, in particular those on the limbs and lower abdomen
For many other operations regional analgesia can complement general anaesthesia and provide lasting and effective postoperative pain relief.
preoperative assessment and preparation as for general anaesthesia .
- full explanation of the procedure, and consent.
- preparation of drugs and equipment for general anaesthesia and resuscitation, in addition to those required for the regional technique chosen.

3. Advantages of regional anaesthesia:
◗ conscious patient, able to assist in positioning, and warn of adverse effects (e.g. in carotid endarterectomy and TURP).
There is less interruption of oral intake, especially beneficial in diabetes
mellitus.
◗ good postoperative analgesia.
◗ reduction of certain postoperative complications, e.g. atelectasis and DVT, possibly myocardial ischaemia

4. Contraindications:
◗ absolute: patient refusal, localised infection.
◗ relative: abnormal anatomy or deformity, coagulation disorders, previous failure of the technique, and neurological disease or other medicolegal considerations

5. Local anesthetic drugs: -
Amide linked local anesthetic drugs;
lignocaine, prilocaine, bupivacaine.
2. Ester linked local anesthetic drugs;
cocaine , benzocaine , amethocaine

6. Commonly used local anaesthetics Drugs
Lidocaine
Medium-acting amide. Maximum safe dose 4mg/kg without adrenaline, 7mg/kg with adrenaline .
Prilocaine
Medium-acting amide. Used for intravenous regional anaesthesia due to its rapid metabolism. Maximum safe dose 6mg/kg without adrenalin, 8mg/kg with adrenaline
Bupivacaine
Long-acting amide. Maximum safe dose 2mg/kg with or without adrenaline.

7. Amethocaine
Long-acting ester. Rapid absorption from mucous membranes or transdermal route.
Benzocaine
Short-acting ester. Used as lozenges
Cocaine
Short-acting ester. Slow onset, profound vasoconstriction by preventing noradrenaline reuptake.

8. Adrenaline: - Added to local anaesthetic solution to: -
Decrease blood flow at the site of injection, leading to decrease vascular absorption & increase neuronal uptake of local anaesthetic, so the depth & duration of neuronal blockade are increased.
2. Decrease the likelihood of high blood level local anaesthetic (decrease toxic reaction to local anaesthetic).
3. In infiltration technique, local vasoconstriction leads to decrease bleeding.

9. Side effects:
If injected intravenously may cause cardiac effect ventricular tachycardia VT, ventricular fibrillation VF, hypertension, and myocardial ischemia.
Should not be used for ring block of digit, penis, tip of nose that may cause vasoconstriction of end arteries & lead to ischemia & gangrene.

10. The clinical manifestations of local anesthetic toxicity
CNS toxicity
Light-headedness, tinnitus, perioral numbness, confusion
Muscle twitching, auditory and visual hallucinations
Tonic-clonic seizure, unconsciousness, respiratory arrest
Cardiotoxicity
Hypertension, tachycardia
Decreased contractility and cardiac output, hypotension
Sinus bradycardia, ventricular dysrhythmias, circulatory arrest

12. Topical anaesthesia: -
Most local anaesthetics produce rapid anaesthesia when applied to mucous membranes.
Sites: eye (conjunctiva), nasal cavity, throat, larynx, ear, urethra.
Application: instillation, spray, ointment, pastes, gels.
EMLA cream: mixture of lignocaine & prilocaine for application to the skin before venipuncture, this is especially valuable for children but take one hour to act.
Lignocaine: 4% maximum 5ml in 70kg man.
Cocaine: 5% maximum 5ml in 70kg man.

13. Nerve blocks: neck
Superficial cervical plexus block
Deep cervical plexus block
Nerve blocks: upper limb
Interscalene brachial plexus block
Supraclavicular block
Vertical infraclavicular block
Coracoid block
Axillary block
Mid-humeral block
Elbow block
Wrist block
Digital block
Intravenous regional anaesthesia–Bier’s block

14. Nerve blocks: trunk
Thoracic paravertebral block
Intercostal nerve block
Inguinal field block
Penile block
Nerve blocks: lower limb
Lumbar plexus block
Femoral nerve block
Lateral cutaneous nerve of the thigh block
Sciatic nerve block
Popliteal sciatic nerve block
Saphenous nerve block
Ankle block

15. Nerve blocks: neuraxial
Spinal and epidural