Spinal Anaesthesia

1. TECHNIQUE OF SPINAL ANAESTHESIA
Presenter : Dr Mohammed Iqbal
Moderator : Dr Amal S Prasad

2. INTRODUCTION

3. • Spinal Anaesthesia aka Subarachnoid Block /
Intrathecal Block
• Regional Anaesthesia
• Injection of LA into SAB
• Dural Puncture
• LA acts at NERVE ROOTS , NOT AT SUBSTANCE OF
SPINAL CORD

4. QUICK ANATOMY

5. • SAS– Foramen Magnum – S2
(Adults) , S3 (Child)
• Spinal cord ends
– L1 LB / L2 UB(Adults)
– L3 ( Child)
• LP done
– below L1 [L3-L4] ( adults)
– Below L3 [L4-L5 ( child)

6. • Spinous processes palpable
, define midline
• Tuffiers /Intercristal line –
L4 (Body) / L4-L5 Interspace

7. TECHNIQUE

8. 4 P’S
• PREPARATION
• POSITION
• PROJECTION
• PUNCTURE

9. PREPARATION

10. PATIENT PREPARATION EQUIPMENT PREPARATION
•PSYCHOLOGICAL PREPARATION
PAC
Informed written consent
Risk documentation
•PHARMACOLOGICAL PREMEDICATION
 BZD
H2 Blockers
•IV ACESS & PRE/CO LOADING
•VITALS MONITOR ( HR/NIBP/SpO₂/ECG)
• CLEAN & DRAPE
• SPINAL TRAY
(prepackaged / custom made )
•RESUCITATION EQUIPMENT
•AMBU BAG
• Laryngoscope
•ET Tube / SGA
•Oral/nasal airway
•O2 support
•Atropine /Adrenaline
•M6/E6 / Phenylephrine
•GA drugs

11. SPINAL TRAY
1) Skin Antiseptics ( Betadine/ Chlorhexidine / Alcohol )
2) 4 x 4 Gauze
3) Fenestrated Drape ( Hole Towel )
4) 2 cc Syringe
5) 26 G x 1.5 “ needle
6) 2 % Xylocard ( local infiltration )
7) Introducer
8) Spinal Needle
9) 5 cc luer lock syringe
10) Single use preservative free LA ampoule

13. SPINAL NEEDLE
• 3 parts : HUB – CANNULA – STYLET
• CANNULA TIP : Bevelled cutting / Pencil point
• STYLET : removable ,tight fitting ,
• 18 G – 27 G (Color coded )
o 22G –BLACK
o 23 G – BLUE
o 25 G - ORANGE
o 26G - BROWN
o 27G - GREY
• 3.5 – 4 “

14. DURA CUTTING NEEDLE DURA SPLITTING NEEDLE
• Bevelled sharp cutting cannula tip
• Egs :
1. Quincke Babcock
2. Pitkins
• Pencil pointed blunt tip
• ↑ Tactile sensation
• ↓ PDPH
•Egs :
1. Whitacre
2. Sprotte

15. • QUINCKE BABCOCK NEEDLE
– Standard Spinal Needle
• WHITACRE NEEDLE
– Pencil point , no cutting edges
– Orifice on one side 2.5 mm proximal to tip
– Exit port smaller than lumen , so greater resistance to injection
• SPROTTE NEEDLE
− Side injection needle with long opening
− Causes more vigorous flow of CSF
− Failed block when only distal part of opening is in subarachnoid space

17. INTRODUCER
• Prevents deflection of spinal needle
• Finer gauge needles can be used
• ↓ PDPH
• ↓ infections
• Avoids epithelial tracking into subarachnoid space

18. CLEAN & DRAPE
 Hands and forearms must be washed and all jewelry removed.
 Scrubbed for at least 3 minutes and Sterile gloves should be applied
 A large area of L-S spine from lower border of scapula to iliac crests should be
painted twice with Betadine and twice with Chlorhexidine using window technique
with sterile gauze
 Area draped – view of T12 – S1 & quadratus lumborum muscle

20. POSITION

21. • Lateral Decubitus
• Sitting
• Prone

22. Lat Decubitus

23. SITTING
• Identification of the midline may be easier
• Obesity & Scoliosis
• With Legs hanging over side of bed
• Put Feet up on a Stool (no wheels)
• Pillow on lap
• Assistant MUST keep the patient from Swaying
• Curve her back like a “C”, ( chin press to sternum )
• Hypotension more common

24. PRONE
• Aka JACKNIFE /BUIES POSITION
• Very rare
• Hypobaric solution
• Anorectal Sx
• No free Flow CSF ,CSF aspiration required

25. PROJECTION & PUNCTURE

26. APPROACH
• Midline
• Paramedian
• Taylor

27. MIDLINE APPROACH

28. MIDLINE IDENTIFICATION
• Post median fissure ≠ Midline
• Spinous process define midline
• Spinous processes palpable
• INTERSPINOUS SPACES : palpating fingers are “rolled” in a side-to-side and a
cephalad-to-caudad direction
• Required INTERSPINOUS SPACE got by counting upward from L4(Tuffiers line)

30. • A subcutaneous skin wheal of local anesthetic is developed over the selected space
• The introducer is inserted at a slight cephalad angle of 10 to 15 degrees through
skin, subcutaneous tissue, and supraspinous ligament to reach the substance of the
interspinous ligament

31. • The introducer is grasped with the palpating fingers and steadied
• Other hand is used to hold the spinal needle like a dart,
• Fifth finger is used as a tripod against the patient’s back
• Fifth prevent patient movement and unintentional deep insertion)

32. • The needle, with its bevel parallel to the midline, is advanced slowly
• With advancement of needle TWO “POPS” are felt. The first is penetration
of the L. flavum & second is the penetration of dura-arachnoid
membrane.
• The stylet is then removed, and CSF should appear at the needle hub
• No CSF flow – rotate needle in 90° increments till CSF appears
• Still No CSF flow , advance needle few mm & recheck in all quadrants

33. • After CSF is free flow, the dorsum of the anesthesiologist’s nondominant hand
steadies the spinal needle against the patient’s back
• Syringe containing the therapeutic dose is attached to the needle
• CSF is again freely aspirated into the syringe, and the anesthetic dose is injected at a
rate of approximately 0.2 mL/s.
• After completion of the injection, 0.2 mL of CSF can be aspirated into the syringe
and reinjected into the subarachnoid space to reconfirm location and clear the
needle of the remaining local anesthetic.

34. PARAMEDIAN

35. • The needle inserted 1 cm lateral and 1 cm inferior of the superior spinous process
of desired level.
• Angle should be 25° toward midline
• No Cephalad / caudad deviation
• LIGAMENTUM FLAVUM is usually the first resistance identified
• Bypasses SUPRASPINOUS & INTERSPINOUS ligaments
• Arthritis , Deformed spine, kyphoscoliosis ,ligament calcification

37. STRUCTURES PIERCED - LP

38. TAYLOR APPROACH

39. • A 12 cm spinal needle is inserted 1 cm medially and 1 cm above the lowest
prominence of posterior superior iliac spine
• Needle is directed upwards medially and forwards at an angle of 50 degrees
• USES :
– Spinal fusion
– Arthritic spine
– Opisthotonus
– Skin infection in lumbar region

40. THANK YOU