SPINAL EPIDURALjshshdjdkdhdbdkdjhdsnd1.pptx

Medical

1. SPINAL,EPIDURAL,CAUDAL ANAESTHESIA MODERATOR:- DR.Vivek Mittal (Prof) DR.Akhil Bhalla (AP) PRESENTER:- DR.Vijayanti

2. CONTENTS Introduction Advantages Anatomy Spinal anaesthesia Indications/contraindications Physiological effects Techniques Grading Complications of sa Epidural anaesthesia – parts,complications,methods for cse Sa vs ea Factors Caudal anaesthesia – indications, contents ,technique, complications, pharmacology

3. 1 st Spinal Anaesthesia in 1898 by August Bier. 1 st Epidural Anaesthesia in1921 by Fiedal pages. In 1945 Tuohy introduced the curved tip needle which is still most commonly used. Central Neuraxial blocks :- It is regional blocks involving subarachnoid-spinal, epidural, caudal spaces. Advantages: Decreases in postoperative morbidity& Sometimes even in mortality. → Reduction in incidence of venous Thrombosis & pulmonary embolism. → Decreases in blood transfusion r equirement. → Decreases incidence of respiratory compromise following thoracic and upper abdominal surgery. → Decreases stress response with the cardiac benefits that is reduce preop and postop ischemia. Introduction

4. ANATOMY OF VERTEBRAL COLUMN:- The spine is composed of the vertebrae and intervertebral disks. There are 7 cervical, 12 thoracic and 5 lumbar vertebrae. The sacrum is a fusion of 5 sacral vertebrae. small rudimentary coccygeal vertebrae.

5. ANATOMY OF SPINAL CORD:- Spinal canal contains the spinal cord with the meninges- pia,arachnoid and dura mater. Subdural and epidural spaces are potential spaces

6. Extends from foramen magnum  At birth, spinal cord ends at lower border of L3  At 1 year- at L2  >12 years- at lower border of L1 (50%) upper border of L2 (40%) body of T12 (5-6%) upper border of L3 (3%)  length- 45 cm (males) 42 cm (females) ANATOMY OF SPINAL CORD:-

7. Dural sac –circular sac surrounding spinal cord Cranially attached to the circumference of foramen magnum Ends at S2 level( 35%) ANATOMY OF SPINAL CORD:-

8. SAGITTAL SECTION THROUGH LUMBER VERTEBRAE

9. DERMATOMES A dermatome is an area of skin innervated by sensory fibers from a single spinal nerve

10. DERMATOMAL LEVELS T4 – nipples T6 – xiphoid T10 – umbilicus T12, L1 – inguinal ligament , crest of ileum S2-S4 – perineum

11. DERMATOMAL LEVELS OF SPINAL ANESTHESIA FOR COMMON SURGICAL PROCEDURES:- Procedure Dermatomal Level Upper abdominal surgery T4 Intestinal, gynecologic, and urologic surgery Transurethral resection of the prostate T6 Vaginal delivery of a fetus, and hip surgery T10 Thigh surgery and lower leg amputations L1 Foot and ankle surgery L2 Perineal and anal surgery S2 to S5 (saddle block)

12. Spinal Anaesthesia:- Standard spinal needle:- 3 parts 1.Hub 2 .Canula ending in a tip 3.Stylet- is removable and occluded the distal lumen and tip of cannula. Tip is made up of stainless steel – stiffness, flexibility, and resistance to breakage.

13. Different size of needles are there. Size-16G to 30G. Luminal size of canula decrease ,the size of needle increase. Bigger gauze needle causes less chance of PDPH.

14. TYPES OF NEEDLE:- 1.Quincke’s 2.Whitacre 3.Sprotte

15. SPINAL NEEDLES QUINCKE-BABCOCK NEEDLE: Standard spinal needle. Small hub , medium bevel length with sharp edges , a sharp tip and end injection. Hub has a luer -lock connector. WHITACRE NEEDLE: Pencil pointed needle Having a rounded tip No cutting edges Orifice is on one side of the cannula about 2.5mm proximal to the tip of cannula with a fitted stylet. Advantage- separate the dural fibers instead of cutting them, thereby reducing size of dural puncture Which causes less CSF leak. Reduces incidence of PDPH.

16. SPINAL INTRODUCERS Types: Sise introducer Corning introducer Lundy introducer Advantage: Avoid bending and breaking of the fine spinal needles. Less chances of infection from skin and subcutaneous tissue entering via tip of fine needles.

17.  INDICATIONS   Lower abdominal, Inguinal, Urogenital, Rectal   G ynaecological & C-section. Lower extremity surgeries . CONTRAINDICATIONS Absolute: Patients refusal Significant coagulopathy Raised ICP Inf ection of the site of puncture INDICATIONS & CONTRAINDICATIONS

18. Severe untreated hypovolemia Valvular heart Ds Relative: Surgical scars Spine deformities (scoliosis) Sepsis Neurological deficits or demyelinating Ds. Uncooperative patients. INDICATIONS & CONTRAINDICATIONS

19. PHYSIOLOGICAL EFFECTS CVS  Hypotension  Bradycardia – Bezold Jarisch reflex  With high sympatheatic block, sympathetic cardiac accelerator fibers arising at T1-T4 are blocked, leading to bradycardia CNS  Sequence of blockage of nerve fibres Autonomic-> Sensory -> Motor (B-A-C)  Recovery in reverse order  Autonomic level is 2 segment higher than sensory which is 2 segment higher than motor - differential blockade

20. Respiratory system  Affected in high spinal/ total spinal  Medullary ischemia d/t untreated hypovolaemia  Systemic toxicity of LA Gastrointestinal  Contracted gut with sphincter relaxation d/t sympatholysis  Nausea/vomiting. Genitourinary system Impaired renal function if MAP < critical pressure for renal autoregulation  Penile engorgement

21. TECHNIQUES OF SA MIDLINE PARAMEDIAN Preparation : explain the procedures in short to the patient. Explain to him the risk and benefits of SA/GA , sensory and motor block and its reversibility. Layers traversed by needle: posterior to anterior Skin Subcutaneous tissue Supraspinous ligament Interspinous ligament Ligamentum flavum Duramater Subdural space Arachnoidmater Subarachnoid space

22. PARAMEDIAN

23.   M onitoring IV access (18G/20G) : 1 TO 1.5 Lit of crystalloid IV solutions   Position: Lateral Decubitus:- Thighs jare flexed up & neck is flexed forward ( Fetal positionn ). Pt should be flexed positioned (Head Low / Head high) to take advantage of the baricity of the spinel LA. Sitting: sit up straight not swaying a Slumping to the side, his head flexed and upper arms hugging & pillow over the Chest. S hould not simply lean forward, he should arch his back to resemble the “ C” . Maximize the opening of the vertebral interspaces. Prone : when surgery pr ocedure (Rectal, perineal, Lumbar procedures).  

24. Monitoring – Block progression & its complications. 1) Ha emodynamics - BP, Pulse rate. 2) Problems with breathing and Sensorium. Hypotension is more pronounced in Who is taking Anti hypertensive Drugs!

25. Complication of SA:- Nausea& vomiting PDPH Caude equine syndrome Anterior spinal artery syn. Meningitis Retention of urine Paralysis of 6th CN Subdural block.

26. Epidural Anaesthesia:- Corning –1st described the Epidural space Epidural space Contents Ant & Post nerve roots, E pidural veins(Batson venous plexus) Spinal artery Lymphatics Fat Fidel pages- 1 st used EA in Humans.

27. Tuohy needle :- 10 can in length. Parts :- -3/½ inch marked with 1cm gradation. HUB which may be w ithout wings or with wings for better control during insertion. Shaft with 1 m markings to measure the depth of epidural space. Blunt bevel having curve at 15-30 degree through which passes the epidural Catheter at an angle and not straight hitting dura or spinal canal. plastic stylet

28. Epidural catheter:- Made up of nylon or PVC. Radioopaque Tip atraumatic, Rounded having Lateral holes & closed end, connector with Luer -Lock cap. C atheter Length - 90-100 cm with markings 5cm, 6, 7cm 8,9, 10, 15, 20 from the tip. Catheter Diameter → 0.9 mm (18G) 1.1 mm (16G) . Colour coded --- Dark Blue (18G), Light Blue (16G). Filter → 0.22 hydrophilic made of mi cr on mesh.

29. LOR syringe - glass or Plastic. LR plunger to identify the epidural space by the LOR Technique. LOR us ing saline for catheter Placement. Complications of Epidural Needle Epidural Hematoma PDPH Backache Epidur a l absces s Epidural catheter:-

30. Complications of Epidural catheters:- 1.kinking, shearing, breaking, knotting. 2.Block, blood dot debris. 3.Accidental dural puncture & c sf leak. 4,Accidental Epidural vein insertion 5.Difficulty in insertion due to nerve root Obstruction. 6.Infection.

31. Spinal Epidural Spinal Epidural 1. simple to perform 1. Difficult to perform 2.rapid onset of Action 2. slower onset of action. 3. small dose of LA 3. Large dose of Large LA 4. DOA shorter 4. Prolong dur ation of Action 5. Reliable Analgesia &muscle relaxation 5. Does not provide reliable analgesia & muscle Relaxation 6. Inability to extend o nce fixed 6. Extension of block 7. Sudden BP drop 7. G radual BP drop. 8. inability to provide PO analgesia 8. Ability to provide.

32. Combined spinal and Epidural:- 3 Methods:- 1.single segment needle through needle. 2. single segment /double barrel method. 3.Double segment method(High epidural and low spinal). FACTORS AFFECTING HEIGHT AND DENSITY OF BLOCK:- 1-Volume of LA-example. if epidural catheter placed at L4-L5 for surgery purpose T4 sensory block then dose of pt will be 12-24 ml of LA. (T4-T12=8)/(L1-L4=4) so 8+4=12, 1-2 ml per dermatomes so we have 12 dermatomes.

33. 2.Age - As the Less pts. Age, less LA required to achieve the same level of block as the younger size & compliance of the epidural space. 3.height of the patient- shorter the Patient Lesser the LA solution required to achieve the same level of Anaesthesia.  4.Gravity: Positioning the patient after the Inj. of LA into epidural space. Ex : positioning the pt Patient after Decubitus position will concentrate LA& extend the block of heigh in the dependent area as compare to non Dependent area

34. PHARMACOLOGY- * Drugs:-- 1)Bupivacaine : 0.0625-0.5% Le vo bupivacaine is Isolated (s) entantiomer of bupivacaine (0.5%), Less CNS & cardiac toxicity as compared to bupivacaine. 2)Ropivacaine :- (0.2-0.75%) L ess potent than bupivacaine 3) Lidocaine -lidocaine 2%.

35. LOCAL ANESTHETIC MECHANISMS Impulse blockade by local anesthetics may be summarized by the following chronology: Solutions of local anesthetic are deposited near the nerve. Removal of free drug molecules away from this locus is a function of tissue binding, removal by the circulation, and local hydrolysis of aminoester anesthetics. The net result is penetration of the nerve sheath by the remaining free drug molecules. Local anesthetic molecules then permeate the nerve's axon membranes and reside there and in the axoplasm. The speed and extent of these processes depend on a particular drug's pKa and on the lipophilicity of its base and cation species. Binding of local anesthetic to sites on voltage-gated Na+ channels prevents opening of the channels by inhibiting the conformational changes that underlie channel activation. During onset of and recovery from local anesthesia, impulse blockade is incomplete and partially blocked fibers are further inhibited by repetitive stimulation, which produces an additional, use-dependent binding to Na+ channels. One local anesthetic binding site on the Na+ channel may be sufficient to account for the drug's resting (tonic) and use-dependent (phasic) actions. The clinically observed rates of onset and recovery from blockade are governed by the relatively slow diffusion of local anesthetic molecules into and out of the whole nerve, not by their much faster binding and dissociation from ion channels. A clinically effective block that may last for hours can be accomplished with local anesthetic drugs that dissociate from Na+ channels in a few seconds.

36.   epidural block by sacral Route   Indications - All Anorectal procedure Haemorrhoidectomy, Transurethral operation. Contents of sacral canal :- Dura l & arachnoid sacs S acral Nerves Blood vessels l ymphatics Alveolar tissue.   Caudal block

37. Technique- I.v canula inserted Lateral position with flexion at hip joint is commonly used to give caudal block as identification of landmark more difficult to palpate. COMPLICATIONS:- 1.Veins may collapse on aspiration it will leads to false negative response. 2.Local anesthetic toxicity. 3.Haematoma formation. 4.Intrathecal injection 5.Sepsis 6.Urinary Retention. 7.Motor blockade 8Rectal perforation