1. Failed spinal anesthesia
Dr. S. Parthasarathy
MD., DA., DNB, MD (Acu), Dip. Diab. DCA, Dip. Software statistics-
PhD ( physiology),
( IDRA )

2. Golden words of 1922 Gaston Labat 1922
Two conditions are absolutely necessary to produce spinal anesthesia:
puncture of the dura mater and subarachnoid injection of an anesthetic agent.
Gaston Labat
1922

3. Define it ?
Spinal Anesthesia is considered to have failed if anesthesia and analgesia have not effected within 10 minutes of successful intrathecal deposition of heavy bupivacaine and 25 minutes for plain bupivacaine

4. Only three options ?? Or more !!

5. Clinical definitions !! 1. Not acted at all 2. Acted but deficient in
a) quantity,
b) Quality or
c) duration ??
Incidence < 1 % some studies 17 %
But acceptable is 3 -4 % in many reviews

6. Incidence

7. Incidence

8. Cant go near !! Failed lumbar puncture Dry tap ??
Needle without the stylet – blood tissue clogs
But not common

9. Faulty position Tip of table Flexion Shoulder straight ?
Kyphosis , scoliosis ? Fracture hip
Previous lamina surgery
The sitting is usually an easier option in ‘difficult’ patients, but sometimes the reverse is true.
The role of the assistant !!

11. Position and adjuncts
A calm, relaxed patient is more likely to assume and maintain the correct position,
so explanation (before and during the procedure)
Gentle slow handling
light anxiolytic premedication
local anaesthetic infiltration without obscuring the landmarks, but must include both intradermal and s.c. injection.

12. Needle insertion Which space ? Midline , hitting bone Cephalad
Rarely inferior and lateral
Get the mental picture
Midline calcification think paramedian

13. Spinal USG

14. Pseudo-successful lumbar puncture
Getting the fluid but not CSF
Epidural top ups
Arachnoid cyst

15. Solution injection errors
Aspiration
Correct dose
Correct drug
Get the feel !! Or
CSF alone is dripping

16. Dose selection Correct dose – specific local anaesthetic used
the baricity of that solution
the patient’s subsequent posture,
the type of block intended,
anticipated duration of surgery
Mass matters

17. Loss of injectate In the needle remains Luer lock Movement
Labour pain ?
Back of the other hand
Aspirate but don’t displace

18. Pencil point needles problems
Pictures from the internet for closed academic purpose only

19. Inadequate intrathecal spread
Anatomical changes,
position,
space injected ,
CSF volume

20. Identification errors Which drug is local Which is test dose
Which is spinal drug
Confusion ?

22. Chemical incompatibility
Clonidine + opioid + LA
LA + 2 opioids
LA with ketamine and midazolam
LA with adrenaline
Not well defined

23. The older, ester-type local anesthetics are chemically labile
heat sterilization and prolonged storage ?? , make them ineffective because of hydrolysis??
Newer Amides are stable

24. “Resistance”
Very rarely a failed spinal anaesthetic has been attributed to physiological ‘resistance’ to the actions of local anaesthetic drugs,
Sodium channel mutation
Scorpion stings !!
Anecdotal

25. This batch is not good !!
The neuroscience division of AstraZeneca received 562 ‘Product Defect Notification’ reports in the 6 year to December 31, 2007, all ascribing failed spinal anaesthetics to ineffective bupivacaine solution
But chemical analyses proved everything Ok in all cases

26. Failure of subsequent management
Level – covert pinch – glance of the eyes between surgeons and anaes – yes OK – start
Abdomen cleaning , mopping – sedatives
Can we stay in an abnormal position for hours ? – table and position are for surgeons

27. Injected proper but ??

28. Tarlov Cyst
Fluid-filled nerve root valved or nonvalved cysts found most commonly at the sacral level of the spine
Asymptomatic TC are present in 5-9 %. Female are more frequently affected
Treatment is drainage of CSF or surgery

29. High CSF volume

30. Volume ??

31. Ballooned dural sac

32. Can happen !!
Some pain fibres pass via sympathetic nerve and then via sympathetic chain to reach the spinal cord at higher level than the site of injection and may be the cause of failure.
Lateral approach -- dural investment of nerve root resulting in false feeling of placement of needle tip in the subarachnoid space

33. Rapid sequence spinal anesthesia – more likely to fail
IV access , monitors with staff 1
Chlorhexidine preparation with staff 2
No local
Non touch spinal
No additives
A larger dose
Start as the block starts
Be Ready for GA
5-7 minutes

34. Non touch spinal by me in 40 seconds

35. Prevention is better than cure
Management of failure
Prevention is better than cure

36. Clinical and medicolegal!!
How and when it is found out
Tincture of time 15 minutes
Then alternative arrangement

37. No block: the wrong solution, the wrong place, or it is ineffective.
Repeating the procedure or conversion to general anesthesia
the patient has significant pruritus, - only opioid injected

38. Good block but less height
Flex knees and hips and trendelenberg
Obstetrics – left and right lateral and head down

39. Patchy blocks
This term is used to describe a block that appears adequate in extent, but the sensory and motor effects are incomplete.
Some sensory and some motor segments spared and quality is not that good.
Repeat – GA – sedation or local infiltration

40. When we repeat Excessive repeat dose – need to reduce !
Higher level of injection
Is it not neurotoxic
Anesthetised nerves prone for nerve injuries
Recourse to an epidural in technical difficulties

41. Rescue measures and GA – beware of already existing sympathetic block and hypotension
Document and explain to patients but avoid medico legal problems
Look for local hospital problems

42. Three muskateers
Right place
Right drug
Right dose

43. Anatomical changes, position, space injected ,CSF volume
abnormalities of the spine, thickened ligamentum flavum, flexible small spinal needle, and improper positioning of the patient or the inexperience of the person giving the block.
Decide
Lumbar puncture
Local injection
Spread
Action on nerves
Failure
Failure
Leaks , partly outside , wrong drugs ,gauge of needle , subdural ,aspirate
Failure
Anatomical changes, position, space injected ,CSF volume
Failure
Bloody taps, high CSF pH, repeated autoclave. resistance, age, drug volume, which drug

44. Alfred E. Barker wrote that for successful spinal analgesia
it is necessary ‘to enter the lumbar dural sac effectually with the point of the needle, and to discharge through this, all the contemplated dose of the drug, directly and freely into the cerebrospinal fluid, below the termination of the cord’

45. Feel and give

46. Failure -Prevention of failure is the most important step
Preoperative noted –
Assess and assure
Sedate
Drugs which increase
Position, valsalva , cough , EVE
Repeat – dose drug !! GA
Intraoperative noted
Assess
Assure
Local
Sedate GA

47. Thank you all