What should be done if a patient has an IV in their right arm while needing blood collected?

In scenarios where a patient has an intravenous (IV) line in one arm and requires a blood collection, the most suitable approach involves collecting from the opposite arm or requesting that the IV be temporarily turned off.

Collecting blood from the same arm with an IV can introduce complications because the IV fluid may alter the composition of the sample, leading to inaccurate test results. Additionally, using the arm with the IV could potentially cause discomfort to the patient as well as complications related to the IV itself.

Choosing to collect from the left arm avoids these issues entirely, allowing for a clean sample that accurately reflects the patient's blood composition. If it is not feasible to use the left arm—perhaps due to another medical concern—asking to temporarily turn off the IV can also be a reasonable solution, provided that this is done under the guidance of healthcare professionals and for a short duration to minimize disruptions.

This method of addressing the IV issue ensures that laboratory results will be reliable and that the patient’s comfort and safety are maintained. It also aligns with best practices in clinical settings, where accurate diagnostic information is critically important.