Emergency Medicine

DIGITAL NERVE RING BLOCK

Practical Procedures 491

(ii) Inject 10 mL of local anaesthetic solution fan-wise, moving

outwards up to 3 cm lateral to the artery.

COMPLICATIONS

1 Femoral artery puncture – avoid by never redirecting the needle medially.

2 Injury to the femoral nerve.

3 Infection.

DIGITAL NERVE RING BLOCK

INDICATIONS

1 Laceration of digit (fingers, thumb or toes).

2 Dislocation or fracture relocation.

3 Management of nail injury/removal.

CONTRAINDICATIONS

1 Peripheral vascular disease.

2 Raynaud’s phenomenon.

3 Local sepsis at the base of the digit.

TECHNIQUE

1 Document a neurological examination prior to the procedure.

2 Use 2% plain lignocaine (lidocaine) without adrenaline (epinephrine).
(i) Do not use a tourniquet due to the risk of creating high pressures
locally and occluding the digital vessels.
(ii) Clean the base of the finger first with antiseptic.
(iii) Insert a 25-gauge orange needle into the side of the base of the
digit, and angle at 45° from the vertical injecting up to 1.5 mL of
2% plain lignocaine (lidocaine) without adrenaline (epinephrine)
into the lateral palmar (plantar) aspect of the digit (see Fig. 18.7).
(iv) Remove the needle until subcutaneous, and rotate until it is
pointing to the extensor surface of the digit. Inject 0.5 mL into
the lateral extensor (dorsal) aspect of the digit.
(v) Perform the same procedure on the other side of the digit.
(vi) Allow at least 5–10 min for the ring block to take effect.

COMPLICATIONS

1 Infection.

2 Digital nerve injury.

3 Haematoma or vascular insufficiency/gangrene of the digit.