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.

Inclusion Criteria: * Adults aged 18 years or older who require intravenous treatment expected to last less than one week and that can be administered through a short peripheral intravenous catheter (PIVC) to be inserted in a participating hospital unit. * A score of 4 or higher on the A-DIVA scale. * Written informed consent to participate in the study Exclusion Criteria: * Patients with an existing peripherally inserted central catheter (PICC), centrally inserted central catheter (CICC), femorally inserted central catheter (FICC), implanted vascular access device (PICC-Port or intravenous port), or tunneled vascular access device. * Patients requiring intravenous treatment that is not appropriate for administration through a short PIVC according to the RNAO vascular access guideline, including solutions with pH \9, osmolarity \>500 mOsm/L, vesicant medications, vasoactive drugs, or parenteral nutrition.