After breast cancer treatment,
Measuring blood pressure involves a simple cuff on the arm which is inflated above the pressure in the arteries, and then rapidly deflated to record the blood pressure. There is no evidence that this makes any difference to the risk of developing lymphoedema or worsen an established lymphedema. However, if you have established lymphedema, the changes in the volume of the arm may affect the accuracy of the recording and for this reason, using the other arm would be more sensible.