US Guided essential nerve blocks for Any Anaesthesiologist

Dr Surjya Prasad Upadhyay

Specialist AnaesthesiologistNMC hospital; DIP

Dubai

USG: Turning art into science

Regional anaesthesia is an art- difficult to master

USG- third eye- making it very easy

With experience/ practice- it will be as easy as putting iv canula.

Higher resolution USG help nerve localisation/ identification

Secret to successful block is the ability to see nerve, needle and LA spread.

History of US guidance

1989: Ting et al; US exam to see LA spread after Axillary block

1994: Reed & Leighton: Doppler to identify Axillary artery before block

1994: Kapral et al: supraclavicular block

1998: Femoral block

2015: cochrane review Ultrasound guidance for upper and lower limb blocks

● 32 RCT/ 2844 pt; 26 UL; 6 LL

● Compared US with other techniques

Use of US alone or with PNS-

● superior sensory and motor block

● Less failure rate.

● Shorter performance time

Ultrasound is superior to other techniques for peripheral nerve blocks

What advantage does U/S bring RA?

● Direct visualisation of nerves/ surrounding

● Appreciation of anatomical abnormality

● Visualisation of needle and its trajectory

● Direct visualisation of LA spread

● Improve Block success

● Faster onset, long lasting Quality of block

● Avoiding complications; (neurologic, LAST, pneumothorax)

How can one learn using US in RA?

● Colleague / friends

● You tube

● NYSORA/ sonosite/ neuraxiom/USRA

● University / teaching hospital

● Conference CME

● Certificate courses

Equipment ● USG machine, probe

● Block kit- Intralipid

● Syringe Needles for block, skin wheal

● Sterile sheath; gel

● LA.

● Resuscitation facility

● Monitor

Basic of USG

● Transducer: US probe – Emit and received US waves.

● Receiving waves- process and image obtained

● Image quality/ Echogenicity: hyper/hpoechoic

● Echogenicity depends on difference in sound emitted and received.

Echogenicity

Basic control of US machine

● Depth

● Gain: improving the returning waves; too much- white out; too low black out.

● TGC: adjusting gain at different depth

● Frequency: higher frequency- better resolution but less pentration,

● Colour mode

● Doppler, M mode

Which probe?

Movement of probes

Basic steps for US guided blocks

1. Preparation: safety guideline

2. Visualisation : scanning

3. Interrogation: identification of target nerve/ area

4. Approximation: needling

5. Deposition: LA deposition

6. Evaluation : post block scanning, block evaluation

The art of needle and transducer manipulation

● Shallow needle trajectory/ appropriate needle size

● Hand eye coordination/ aligning needle with US beam

● Proper agronomics

● Always concentrate on tip rather than the shaft.

● Lost needle? Move the probe

Indirect way of needle tip localisation

● Tissue movement

● Tactile feedback

● Hydrodisection

Out of plane Vs in plane

General guideline

● Aspirate first then Inject 1 ml to confirm needle tip.

● Should be no aspirate, resistance, pain, paresthesia on injection

● Aspirate every 5 ml

● Watch for spread of LA

● Never inject while needle is in motion

● Lost needle? Never try to move needle blindly

● Move the probe to find the needle

Upper extremity blocks

Brachial plexus block

Distal branches block

Brachial plexus block

Axillary Block

● Area cover: below elbow

● Position – supine; arm abducted

● Transducer position: short axis to arm

● Depth:2-3 cm

● Landmark; Axillary/brachial artery

● 22G; 50 mm needle

● In plane/ out of plane

Cross section / sono-anatomy

Axillary block:

● Easy and simple and safe block: basic block for learner

● Nerves around the artery can be seen.

● Doughnut around Axillary artery with LA is sufficient for success

● Mostly done in plane: cephalic to caudad

● Duration with 30 ml of 0.5% Bupivacaine=12-15 hrs

● Safe for obese, COPD, need for B/l block: phrenic spare

Infraclavicular Block

● Technically most difficult brachial block;

● Best for catheter placement and fixation

● Patient position: head up and turn away;

● Houdini Arm: displaced clavicle posteriorly

● Transducer: parasaggital,medial to choracoid

● Depth: 3-5 cm

● Landmark : Axillary artery;

● LA: 20-30 ml

Infraclavicular block

Infraclavicular block:

3 key point for excellent needle view

● Houdini arm

● Insert needle further away from transducer

● Rock the transducer towards the needle for better view

Infraclavicular block

Supraclavicular block

● Fast onset; dense block, high success;

● Head up and turn to opposite

● Arm adducted/neutral

● Posterior Room for needle

● Linear transducer:

● transversely just above mid clavicle

● Needle: 22 G, 50 mm

● LA-15-25 ml

Supraclavicular brachial block

Technique of block

● In plane: lat to meadial, anterior approach in difficult cases

● Out plane- possible, but risky

● Identify; sabclavian A, rib, pleura,

● Go deep first and inject the corner pocket

Interscalene brachial block

● Bread & butter for shoulder surgery; cover all shoulder surgery

● Block target at root level C5-7

● US highly recommended; high complications with landmark.

● With US; Block can be performed with as little 8-12 ml.

● In plane – anterior and posterior approach

● Out of plane: preferred for catheter placement

Interscalene brachial block

ISC: sono-anatomy

● Scanning technique

● Head up, rotate to other side

● Scan supraclavicular area-

● Depth 2-3 cm

● Trace transducer Up

● Look for ASM/ MSM

● Three roots of BP: traffic signal

ISC / Inplane/ Out of plane

Truncal blockade

Rectus sheath

Transversus Abdominis plane (TAP)

Rectus Sheath block

● Recus sheath- continuation of IO, EO; linea alba @ mid-line

● Ant sheath- interrupted by tendinous brands

● Probe- linear,

● paramedian- between umbilicus and costal margin

● Out of plane or in plane

● Target- posterior rectus sheath @ lateral end

Rectus Sheath Block

TRANSVERSUS ABDOMINIS PLANE (TAP)

● Most versatile block; field or plane block

● Safest block; technically easy

● Potential alternative to epidural analgesia.

● Different name as per anatomic

● Anterior lower TAP- Ilioinguinal- iliohypogastric

● Anterior - Mid axillary- classic TAP

● Lateral to Rectus in subcostal TAP

● Extreme Posterior TAP- QLB

TAP Anatomy

TAP nomenclature

1. Upper subcostal TAP - (T7 and T8),

2. Lower subcostal TAP (T9, T10 and T11)

3. Lateral TAP (T10 and L1)

4. Ilio-inguinal TAP (T12 and L1)

5. Posterior TAP- QLB 1&2

Classic TAP

● Transducer transversely- ant-mid axillary line

● Anywhere between costal margin to iliac crest

● Identify 3 muscle layer- EO, IO, Tr Abdominis

● Aim is to deposit LA (15-30 ml) between IO fascia and TA

● May need curvilinear probe in obese

● Area covered unilateral T10-L1 area

● Skin, muscle and perietal peritoneum

Ilioinguinal- iliohypogastric

● High frequency linear transducer

● Depth- 3-5 cm; 5-8 cm needle

● Transducer – oblique,

● line joining umbilicus to iliac crest

● 2.5 cm up and medial to ASIS

● Inplane/ out of plane

● LA-10-20 ml; between IO & TA

IIN/IHN TAP plane

Subcostal TAP: T7-T10

Subcostal TAP

Bilateral Dual TAP (BD-TAP)● B/L Subcostal TAP + B/L- Classic TAP; 4 point block

● Anaesthetised Entire abdominal wall

BD-TAP or B/L Rectus + TAP

BD-TAP

Block for Laparoscopic Surgeries

TAP block (Tricks)

Anatomy:IO fascia

Improper: LA above IO fascia Proper LA deposition

Lower limb Block

Fascia Iliaca Compartment Block

Femoral Nerve Block

Popliteal sciatic block

Fascia Iliaca Compartment Block (FICB)

● Volume dependent; filed or compartment

● Technically easy

● Area : Hip, anterior-lateral thigh, knee

● Different techniques

● Probe: transverse,

● close to the femoral crease, lateral to FA

● Target area: just below Fascia iliaca

● Volume -30-50 ml

Anatomy: FICB

Sonoanatomy

● Transducer at Femoral crease, Lateral to medial

FICB: technique

● Linear probe

● Either in plane or out of plane

● Landmark- Lateral to FA; lateral 3rd of ASIS to FA

● LA between- Iliacus muscle and its covering fascia

Femoral Nerve Block

● Area covered: Anterior thigh, femur, knee

● Similar to FICB; but more medially

● Landmark- inguinal crease, lateral to FA

● Depth 2-4 cm

● Deposit LA just lat to FA around FN

● LA-10-20 ml

Popliteal Sciatic

● Area cover:

postero-lateral

aspect below knee

foot; tibia, fibula

Scanning technique

Popliteal Block

● Either lateral or prone

● Linear Transducer;

● Depth-3-5 cm

● 8-10 cm needle

● Target area; at the bifurcation of sciatic

● LA-15-25 ml

● Selective tibial: Knee surgeries

Documentation

● Indication

● Pt status at the time of block

● Preparation

● Scanning: Anatomy; image quality

● Approach: in plane out of plane

● Needle:

● LA used.

● Pain, paresthesia, resistance

● Problem encountered / complications

● Block success

Conclusion

● Ultrasound provides significant other benefits compared

to pre-existing techniques

● US guided: Simplified and provide Superior quality of block

● US increases the practice of RA---> improved periop outcome

● So use of US leads to improve peri-operative outcome

● Ultrasound is a standard of care in RA.