What to do for a swollen Arteriovenous Fistula (AVF) after a missed cannulation?

Management of Swollen AVF After Missed Cannulation

Immediately withdraw the needle, apply manual pressure to the infiltration site, and apply ice for at least 10-30 minutes depending on the size of the hematoma—do not attempt to re-cannulate the affected area until swelling has completely resolved and anatomical landmarks are clearly visible again. 1

Immediate Management Based on Infiltration Severity

Small Infiltration

• Apply ice for a minimum of 10 minutes to the affected area 1
• Refrain from maximizing the blood pump speed during the current dialysis session 1
• Continue dialysis if already initiated, monitoring closely for progression 1

Moderate Infiltration

• Withdraw the needle immediately and hold manual pressure over the infiltration site 1
• Apply ice to decrease pain and reduce the size of infiltration 1, 2
• Elevate the affected arm as much as possible to reduce swelling 2
• Rest the access arm completely 2

Large/Significant Infiltration

• Withdraw the needle and apply manual pressure plus ice for 30 minutes before any further intervention 1
• Decide whether dialysis is urgently needed that day 1
• If dialysis cannot be postponed, cannulate proximal to the infiltration injury only—never reattempt at the area of injury 1, 3
• If proximal cannulation is not possible, establish alternative temporary access rather than forcing cannulation near the hematoma 3

Comprehensive Assessment Requirements

Perform a close assessment of the site, the AV access, and the adjacent extremity including:

• Measurement of swelling extent 1
• Assessment of flow presence in the AV access both proximal and distal to the hematoma 1
• Evaluation of circulation to the associated extremity 1
• Check for presence of high-frequency bruit on auscultation and difference in intravascular pressure on palpation 1

Critical Warning Signs Requiring Urgent Intervention

• Bleeding requiring skin suture or resulting in very large hematoma strongly suggests venous outflow stenosis and mandates referral for diagnostic angiogram 1, 3
• Loss of thrill or bruit indicating possible thrombosis 2
• Severe pain, coldness, numbness, or weakness in the hand suggesting steal syndrome 4
• Compression of the vessel by hematoma that could result in thrombosis 1

Timing for Re-cannulation

Do not attempt re-cannulation until:

• All swelling, induration, and edema have completely resolved 3
• Anatomical landmarks are clearly visible through inspection and palpation 3
• The vessel has been assessed and confirmed to be normal and appropriate for cannulation 3
• This typically requires 3 weeks to 3 months depending on hematoma size 1

The decision must be based on clinical resolution, not arbitrary time intervals 3. Repetitive attempts to cannulate through or near an existing hematoma carry high risk of inaccurate placement and may lead to permanent vessel loss 3.

Imaging Evaluation

• If swelling persists beyond 2 weeks, obtain imaging to evaluate for underlying causes 2
• Duplex ultrasound is preferred for initial evaluation as it avoids diagnostic cannulation of the injured AVF 1
• If stenosis >50% is found with associated clinical abnormalities (reduced flow, increased static pressures, abnormal physical findings), proceed with percutaneous transluminal angioplasty 1, 2

Infection Exclusion

• Evaluate for signs of infection including erythema, warmth, tenderness, purulence, or systemic symptoms 2
• If infection is present, immediately initiate broad-spectrum antibiotic therapy with vancomycin plus an aminoglycoside for 6 weeks 2
• Cannulation at the inflamed site must cease immediately 2

Common Pitfalls to Avoid

• Never apply pressure to needle sites before the needle is completely removed—this prevents infiltration 4
• Do not occlude the AV access outflow distal to the bleeding site when applying pressure, as this increases intraluminal pressure to arterial levels 1
• Do not attempt cannulation at sites where margins of the fistula are not well demarcated 1
• Only staff with demonstrated technical mastery should attempt cannulation of vessels with prior hematoma formation 3

Alternative Access Strategy

If a significant hematoma develops requiring prolonged rest (potentially up to 3 months), placement of a central venous catheter may be necessary to maintain dialysis access during the healing period 1. This prevents the temptation to prematurely re-cannulate the injured site.