Local / regional anaesthesia MUDr. P. Nohel, MUDr. L.Dadák FN u sv. Anny v Brně ARK Anesthesia = znecitlivění anaesthesist • general (narcosis) • local / regional • combined Local anaesthetic • reversible block • Sodium ion canal (Na+ to cell) Nerve fibre • A: myelin – a (alfa): locomotion, reflex activity a proprioception – b (beta): touch press – g (gama): muscular tonus – d (delta): PAIN and sense of heat • B: thin, myelin preganglion-nerve fibre, vegetative function, smooth muscle of vessels • C: non-myelin, PAIN Nerve block - signs • (B fibre) block of sympaticus = heating • (C + Ad fibre) block of pain and heat • (Ab) ztráta pocitu doteku • (Aa) motorická blokáda Local anaesthetics potentially toxic! • CNS – convulsion, coma, depression of breath! • lost of sensitivity around mouth, iron taste on tongue, somnolence, vertigo, tinitus (ringing), nystagmus, changes in seeing • cardiovascular system – hypotension, bradycardia, colaps of circulation, asystoly or ventricular fibrilation! Lokal anaesthetics • aminoester • aminoamid • examples: lidokain, trimecain (Mesocain), bupivakain (Marcaine), prokain, artikain (Ultracain, Supracain), ropivakain (Naropin) Types of anaesthesia • Local – skin, mucosa – infiltration • Periphery block – nerves – nervous cluster • Central block – subarachnoidal (spinal) – epidural Local anaesthesia • Local anaesthesia – superficial (topic, mucosa) – infiltration Central block • epidural • subarachnoideal (spinal) Anatomy of back bone canal • 7 C, 12 Th, 5 L, 5 S a 4-5 Co • spinal cord L1/2 • spinal cord cover (pia mater, arachnoidea, dura mater) • ligamneta (ligg. supra- , interspinalia, lig. flavum) • epidural a subarachnoideal space Míšní dermatomy Central blocks • Indication: – lower extremity, lower abdomen , perineum – part of combine anaesthesia – continual technic for treating of postoperative pain – childbirth analgesia and anaesthesia • Contraindication – disagreement of patient – infection in place of prick – hypotension, hypovolemia, shock – valve stenosis - fixed cardiac output – blood abnormalities (warfarin, heparin) Systemic effect • Cardiovaskular system – block of sympaticus • hypotension • stagnation of blood in veins, small vein return • relative hypovolemia • Ventilation: small influence • Urination: retenction (block of urine bladder) Subarachnoideal anaesthesia Subarachnoideal space - wall: arachnoidea + dura mater - content: spinal cord, nerves, cerebrospinal fluid liquid in cerebrospinal fluid: isobaric, hyperbaric, (hypobaric) Dose: 2 – 4 ml (saddle block 1 ml) Motoric block Epidural anaesthesia • Epidural space – posterior border: lig. flavum + vertebral arches – content: fat connective tissue, lymphatic vessels, vessels for vertebra and spinal cord, radices of spinal nerves, spinal cord, spinal covers – thickness of epidural space> • lumbar: 5 - 6 mm • thoracic: 3 - 5 mm • cervical: about 3 mm Epidural anaesthesia • Spread of anaesthetics: – both direction from the end of needle or catheter – part is disappear through intervertebral apertures, part diffuse to CSF and pith • Doses: ower 150 cm 1 ml/segment + 0,1 ml/segment for each 5 cm Equipment Loss of resistance Hanging drop Stimulator Peripheral blocks • single nerves • nervous cluster Plexus brachialis