Arteriovenous (AV) Fistula

Anesthesia Implications

Position: Supine, one arm extended, Bed turned 30 degrees
Time: 30-60 min (short)
Blood Loss: Low (10-50 ml)
Post-op Pain: Minimal (1-3)
Maintenance Paralytic: No

Blocks: Axillary

Anesthetic Approaches

  • MAC, Propofol Drip
The Anesthesia

IV – Preoperative IV should NOT be in the operative arm. These patients are usually difficult sticks.

Block – An Axillary block with a T2/intercostobrachial (ICB) is great for almost all AV fistula creations. Multiple pros also suggest a supraclavicular and ICB combination. Some of the benefits of blocks in cases like these include arterial and venous dilation, which allows the surgeon to avoid use of PTFE gortex grafts in some patients.

Intraoperative Drugs – The surgeon may ask for heparin and protamine.

High Fistula Block – For high fistula creation, a supraclavicular block is what most providers choose. However, the downside to using this block is possible phrenic nerve blockade which will add more respiratory risk to patients that are potentially already volume-overloaded. Infraclavicular is as good as Axillary and no risk of shortness of breath. But needs to combined with T2/ICB of high up in arm.

Ischemic Monomelic Neuropathy (IMN) – After placement of an AV fistula, there can be shunting of arterial blood away from the distal extremity. This results in acute neurological symptoms/pain. This is called Ischemic Monomelic Neuropathy. A short acting local (lidocaine) should be used in case of IMN ischemic monomelic neuropathy. This is a condition that can happen with AV fistula creation at any level, but at the antecubital space and higher there is risk of nerve injury and pain that will not get better until fistula is ligated.

Hyperkalemia – Watch for the signs of Hyperkalemia – Check the most recent potassium. Hypoventilation with sedation will worsen hyperkalemia.

Last dialysis date – this is important. The patient could be dry or fluid overloaded.

Sick patients – these patients are usually pretty sick with minimal kidney function and multiple comorbidities, so reducing drug dosages is a very good consideration. For patients with severe OSA, some have found success using a precedex drip (instead of propofol) and supplementing with a ketamine push diluted down to 5mg/ml to maintain respirations during the case.

The Surgery

This surgery is performed to bridge an artery to a vein. The high pressures of the arterial system causes the vein to expand over time. This expanded vein (fistula) is ideal for access when dialysis is prescribed.