1. Xavier Paqueron MD, PhD
Clinical Centre, Angoulême, France
Ultrasound-guided regional anesthesia. :
What do ultrasound bring to regional anesthesia ?
xavier.paqueron@orange.fr
4. Private 300 beds Hospital
My Institution : The Clinical Centre
Ambulatory Care Unit
Surgery
• Orthopedic
• Hand
• Urologic
• Vascular
• Abdominal
• Gynecologic
• Breast
• OPH
• ENT
Obstetrics
Pain Clinic
Medicine
• Oncology
• Internal medicine
• Cardiology
• Pneumology
www.centre-clinical.fr/
Regional anesthesia room
PACU
5. Current place of regional anesthesia
① Postoperative pain control
② Improved postoperative recovery
③ Alternative to GA
④ Ambulatory surgery
⑤ PONV
1
6. RA superior to morphine during the 2 first postoperative days
0
2
4
6
8
10
24 Hrs 48 Hrs
catheter
opiates
0
1
2
3
4
24 Hrs 48 Hrs 72 Hrs
catheter
opiates Mean VASMax VAS
Continuous blocks = the reference
15. Casati 2007, Orebaugh 2007
Reduction of number of needle trajectories with USGRA
Perceived pain is less frequent
20 % with USGRA vs 48 % nerve stimulation
16. How USGRA does improve safety ?
① Control of needle tip
② Diagnose early
• intravascular
③ Reduce toxicity
• Reduce volumes
④ Diagnose early
• Intraneural
3
17. Always believe that what you think is the needle tip may not be it
Control of needle tip - Whatever the approach
Always consider you may not see the needle tip
25. UltraSound-Guided Regional Anesthesia
doesn’t avoid nerve damage
Two recent case reports of persistent nerve damage with
• No pain
• No paresthesia
• at least one followed an intraneural injection
27. Ultrasound
Contribution
The anesthetist is no longer blind
• Accuracy ~ 1 mm with high frequency probes
Visualisation of one third of all fascicles
Silvestri et al. Radiology 1995
• Fascicles size ~ 0.25 - 0.5 mm
28. Ultrasound
Contribution
Contact between nerve and needle
• motor response ≤ 0.5 mA: 74.5%
• paresthesia: 38.2%
Perlas RAPM 2006
Stimulating needle can
touch a nerve with no
motor response !
29. Bigeleisen 2006
Frequent intraneural /
subepineural injection of
local anesthetics
… under US guidance
Nerve swelling = 70%
Ultrasound
Contribution
30. Bigeleisen 2009
Ultrasound-guided supraclavicular block
and nerve stimulation
1. Needle-nerve contact
Ä minimal stimulating current
2. Needle advanced intraneurally
Ä minimal stimulating current
Ultrasound
Contribution
32. Better understanding of the limits of nerve stimulation
• Intraneural injection is (very) frequent
• MIS ≥ 0.5 mA : No guarantee of being extraneural
• Contact needle-nerve without motor response = frequent
• Subepineural needle placement without motor response = frequent
• Intraneural injection without pain or paresthesia
… and without nerve damage
Ultrasound
Contribution
33. Sala-Blanch 2009
Needles through human
sciatic nerve
Intraneural injection & nerve damage
More likely: transverse the nerve between
the fascicles rather than through them
34. A- EXTRA NEURAL
Extraneural connective tissue
B- EPINEURAL
Connective tissue between fascicles
C- INTRA-FASCICULAR
Into (between) nerve fibres
I choose where I inject…
Ultrasound contribution
35. • probability of subepinerium location of needle tip
• If motor response at an intensity < 0.2 mA
• Use a test dose (1 ml) = hydrolocation
• If you see
• Swelling = STOP all further injection (subepineural)
• Nothing when you inject = iv injection or needle tip not in US beam
• If you stop the injection
• In case of swelling … unknown risk!
• When nothing appears = risk well known (intravascular)
Nerve swelling after 1 ml
Motor response < 0.2 mA
Ultrasound contribution
needle tip is
Subepineural
41. Improve efficiency with Ultrasound
Cheaper
Compared with
Nerve stimulation
Improved success rate
• Less time to perform blocks
• Reduction of volumes
• Improve patient comfort
Easy learning
• Rapid learning curve
ü See needle tip
ü Unintentional probe
movements
42. Improve safety with Ultrasound
Decrease LAST
• Monitor needle tip
• Reduce volumes
• Detect intravascular
injection early
Decrease Nerve damage
• Don’t inject intraneurally = No nerve swelling
• Association with nerve stimulation
• Monitor injection pressures
• Use blunt tip needle
• Monitor needle tip