2. HISTORY
īĸ August Bier introduced this block in 1908.
īĸ In 1963, Holmes popularized the Bier Block.
īĸ Completed within 40-60 minutes.
īĸ Onset of anesthesia is rapid and reasonable
muscle relaxation.
3. CONDITIONS
1.Surgical procedures involving the arm below the
elbow.
2.Surgical procedures involving the leg below the knee.
īĸ Ensure that the patient has been fasting for an
appropriate period of time.
5. There appears to be multiple and complementary
mechanisms for producing analgesia and anesthesia.
FACTORS RESPONSIBLE:
īĸ A large volume of dilute anesthetic
īĸ Ischemia
īĸ Asphyxia
īĸ Hypothermia
īĸ Acidosis
6. HYPOTHERMIA&ACIDOSIS
Hypothermia and acidosis results in enhanced local anesthetic activity.
ASPHYXIA
Asphyxia occurs at 20-30 mins complementing local anesthetic action.
Local anesthetic molecules transverse venous walls into surrounding
tissue.
INJECTION OF LOCAL ANESTHETIC
Initial analgesia produced by local anesthetic action on major nerve
trunks, small nerves, and nerve endings.
SEQUENCE EVENTS RESULTING IN ANESTHESIA &
ANALGESIA:
7. EQUIPMENTS
A standard regional anesthesia tray is prepared with the
following equipment:
īĸ 22-gauge intravenous catheter
īĸ Flexible extension tubing
īĸ 5" Esmarch bandage
īĸ Double cuff tourniquet
īĸ 20 mL syringes with local anesthetic
īĸ Pressure source
īĸ A double-cuff tourniquet
8. PROCEDURE:
1. A small IV intravenous catheter (e.g, 22-gauge) is
introduced in the dorsum of the patient's hand of the
arm to be anesthetized. The patient is in the supine
position.
9. 2. A tourniquet is
placed on the proximal
arm of the extremity to
be blocked. We use a
"double cuff" to increase
the reliability of the
technique and help reduce
the tourniquet pressure pain.
11. 4. Apply wide Esmarch rubber
bandage to complete the
exsanguination of the
extremity.
12. 5.Elevate arm to promote
venous drainage. The
Esmarch is then unwrapped
and the extremity is checked
for color (pale skin) and
arterial occlusion
(absence of the radial pulse).
13. 6.The extremity is then lowered
and the local anesthetic is
slowly injected through the
previously inserted IV
catheter.
14. POST PROCEDURE
īĸ Analgesia will occur within 3-4 minutes.
īĸ Even if the surgery is completed within a few minutes,
on no account should the tourniquet be deflated until at
least 15 minutes has passed.
īĸ The pressure in the tourniquet must be constantly
observed and maintained at least 50mm Hg above the
patient's systolic blood pressure.
15. īĸ If the operation is prolonged, the patient may
complain of pain due to pressure from the
tourniquet. This may be reduced either by the
subcutaneous infiltration of a few mls of local
anesthetic above the tourniquet or by the use of a
"double tourniquet techniqueâ.
īĸ At the end of the procedure, the tourniquet is
deflated and normal sensation quickly returns.
īĸ The tourniquet is reinflated again 20-30 seconds.
16. ADVANTAGES OF THE BIER BLOCK
īĸEasy to administer
īĸLow incidence of block failure
īĸSafe technique when used appropriately
īĸRapid onset and recovery
īĸPatient is awake during procedure.
īĸControllable extent of anesthesia.
17. DISADVANTAGES OF THE BIER BLOCK
īĸShould be used for only short procedures
īĸPatient may experience tourniquet pain after
20-30 minutes
īĸSudden cardiovascular collapse or seizures
may occur if local anesthetic is released into
the circulation too early.
īĸ Lose pulse
īĸRapid recovery may lead to postoperative
pain
īĸDifficulty in providing a bloodless field
18. CONTRAINDICATIONS
īĸReynaudâs disease
īĸHomozygous sickle cell disease
īĸYoung children
īĸUnreliable or inadequate tourniquets.
īĸShock
īĸMultiple trauma (crush injuries of relevant
limb)
īĸHypersensitivity to Prilocaine or lidocaine
īĸSeizure disorder
19. DRUGS
1.PRILOCAINE
īļ The drug of choice as it is least toxic
īļ largest therapeutic index.
īļ One complication is methemoglobinemia . Prilocaine is
metabolized to o-toluidine derivatives, which converts
hemoglobin to methemoglobin.
īļ onset 2 - 15minute and duration 1 â 4hours.
2.BUPIVACAINE
īļ not suitable
īļ it is too toxic, particularly to the myocardium.
īļ Slower onset .
20. 3.LIGNOCAINE
īļ acceptable alternative.
īļ onset 1.5 - 5minute and duration 1 â 4hours
DOSAGE
īĸ the arm dosage can be: 30-40 ml of 0.5%
prilocaine or 0.5 % lidocaine.
īĸ In leg, larger volumes 50-60 ml.
22. 4. Toxicity of local anesthetics
īĸ Signs and symptoms may include nausea,
vomiting, dizziness, tinnitus, funny sensation
around the mouth, loss of consciousness.
Local Anesthetic Toxicity Management
īĸ Use the A, B, Câs for the management of local
anesthetic toxicity.
īĸ A= airway. administer 100% oxygen.
īĸ B= breathing. May need to assist the patient with
positive pressure ventilation or intubation.
īĸ C= circulation. Check for a pulse..
23. CONCLUSION
IVRA is a simple and valuable technique that is
easy to learn and perform. It is very safe
provided excessive doses of local anesthetic are
avoided, if the tourniquet pressure is carefully
monitored and if resuscitation equipment is
always immediately available.