Near-Infrared Light for Peripheral Venous Catheterization in Adults With Difficult Venous Access

The goal of this clinical trial is to learn whether near-infrared (NIR) light can help healthcare professionals place a peripheral intravenous catheter in adults with difficult venous access. The main question it aims to answer is: \- Does using NIR light make successful catheter placement on the first needle puncture more likely than the usual method of looking for and feeling the vein? Researchers will compare NIR light with the usual method of looking for and feeling the vein to see which method works better for placing the catheter on the first needle puncture. Participants will: * Have their veins located using either NIR light or the usual method of looking for and feeling the vein. * Have a peripheral intravenous catheter placed by a healthcare professional. * Report their pain and satisfaction with the procedure. Researchers will also record how many needle punctures are needed, how long catheter placement takes, how long the catheter remains in place, why it is removed, and whether any complications occur.