The Mastectomy Arm and the Running IV

Rule out both arms first, then escalate.

• Right arm - never. Axillary lymph node dissection on that side creates lifelong lymphedema and infection risk; venipuncture, BP cuffs, and IVs are avoided on that side. Cellulitis in the same arm makes it doubly unsuitable.
• Left arm - usable only with conditions. The IV is running in the forearm. Drawing above a running IV is unacceptable: the specimen is diluted by infusate and hemolyzed, and the stick can infiltrate the line.

Before uncapping anything:

1. Notify the nurse or charge nurse that a STAT coag study is ordered and both arms have constraints. This is a provider-level decision, not an MA decision.
2. Ask the provider to clarify the order - either authorize a distal draw below the IV site, or authorize a different route (a second line started by the RN in the opposite hand, or a lab draw with a phlebotomy team).
3. Do not simply proceed because the patient points at an arm. Patient preference does not override standard of care; explain why, and offer to have the nurse or provider speak with her.

Document the notification time, who was notified, and the site ultimately used with its relation to the IV.

Response (acknowledge, explain, offer choice within limits):

'You are right that it is your body, and I am not going to stick you anywhere without telling you why. The problem is that this arm had lymph nodes removed, so a needle there can cause permanent swelling and infection - that is why your surgeon's team flagged it. And drawing above the IV would give us results we cannot trust, which means sticking you twice. I have asked the nurse to get the doctor to approve a plan, and I will be back in a few minutes with the option. If you want to talk to the doctor or the nurse directly, I will bring the phone to you.'

• Do not bargain toward the contraindicated arm or imply it is a paperwork formality.
• Offer legitimate control: which acceptable site, who performs it, whether a topical anesthetic or smaller gauge is used.

Document: patient's stated preference and refusal of the right arm rationale; education given in plain language; the escalation and time; who authorized the final site; the patient's response. If she refuses all acceptable sites, the refusal is documented and reported to the nurse/provider - it is not overridden, and it is not recorded as noncompliance in a judgmental way.

Technique

• Tourniquet and stick distal to (below) the IV site only; never above, never on the same vessel segment.
• Do not draw from the IV catheter itself unless the MA is trained and specifically ordered to; if the line is used, the RN must flush and discard per policy.
• Let alcohol dry; prolonged tourniquet time and small-gauge vacuum tubes increase hemolysis.
• Mrs. Alvarez is on warfarin: hold pressure 5+ minutes, check for hematoma, apply bandage.

Results that may still be wrong

• PT/INR: most vulnerable. Heparin or heparin-locked lines and any dilution distort coag results; if there is any doubt about infusate, the specimen is not reportable for coag.
• Potassium: falsely high from hemolysis.
• Glucose: falsely low from fluid dilution.
• CBC: dilution lowers counts; hemolysis inflates or deflates indices depending on the analyzer.

Flag the specimen with the draw site and IV location on the requisition/label so the lab knows. If the result is critical or unexpected, the provider should be told the specimen came from distal to a running IV - retesting proximally, or from the other side after medical clearance, may be required.