Bier Block Flashcards
How does the bier block work?
Exsanguinate extremity by compression and occlude with pneumatic tourniquet
What types of cases is the bier blocked used in?
Hand/forearm
Can use in lower extremity in leg/foot
What is the limiting factor of the bier block?
Duration: 90-120m
At what point might the tourniquet become very painful to the patient?
After 30-45 minutes
What type of tourniquet must be used for a bier block?
Double wide cuff, two ports that are capable of having two different pressures
What type of IV should be placed in a patient receiving a bier block and where should it be placed?
IV 22g or less with the cannula as distal as possible on operative extremity
How can the provider aid in promoting venous drainage from the extremity?
Elevate the extremity
What is the purpose of the esmarch elastic bandage?
To exsanguinate all of the vascular tree of the extremity
What can occur if the esmarch bandage it wrapped too tightly around a ganglion cyst?
Could rupture the cyst
When placing the tourniquet on the patient, why is it important to know the difference between the two port sites?
One is proximal and one is distal, need to know this for inflation
In what order should the tourniquet be inflated when performing a bier block?
Distal cuff first then the proximal and then deflate the distal
What is an appropriate pressure to inflate the tourniquet to?
50-100mmHg greater than the systolic
What is the maximum amount to inflate the tourniquet in the upper and lower extremity?
Max 300 in arm
Max 400 in leg
Why do we deflate the distal cuff once the proximal has been inflated?
So LA can get under the distal cuff to anesthetize the area
What is the importance of tourniquet bounce?
Bounce indicates that the cuff is inflated
What type of LA should be used when performing a bier block?
Lidocaine 0.5% preservative free, WITHOUT vasoconstrictor
How much volume should be injected for a bier block?
30-50mL
What is the onset of a bier block?
About five minutes, may complain of hot, burning, pins and needles sensation
What should be done to the catheter once LA is injected?
Should be taken out and firm pressure should be held on the site to prevent LA from bleeding out
What is the goal of a bier block?
To exsanguinate all of the vascular system in the extremity and fill it with LA
Why might the provider hold the wrist tightly while injecting the LA in a bier block?
Acts as a tourniquet to keep LA in area for longer period of time
If a patient begins to complain about tourniquet pain, what can the provider do to relieve this?
Inflate the distal tourniquet where LA has anesthetized the area and then deflate the proximal cuff after confirming the distal is inflated
Why must tourniquet time be greater than 20-30m?
Gives time for the LA to be metabolized, otherwise they will receive a large bolus IV and may experience LAST
How should the provider proceed if the tourniquet is 20-40m long?
Release briefly then immediately reinflate, observe 1m for LAST
Repeat the process if no signs of LAST, deflate and remove
How should the provider proceed if the tourniquet time is greater than 40m?
Deflate slowly and observe for signs of toxicity
What are complication associated with a bier block?
Premature release of LA often associated with tourniquet failure –> May result in LAST
Hematoma
Engorgement of extremity
Eccymoses and subcutaneous hemorrhage
How should the provider treat a patient that may be experiencing LAST?
Quickly isolate the extremity and support ventilation/circulation
