The integrated system for difficult veins facilitates cannulation of cancer patients with difficult veins thanks to the unique butterfly introduction technique. It also has the ability to minimize injuries caused by needle puncture through an automatic protection mechanism that involves the entire needle. In addition, it minimizes exposure to blood during the introduction. The combination of Vialon material, large and smooth wings and an integrated extension help to improve the stabilization of the catheter in the vessel, minimizing the complications associated with the catheter and improving the catheter's stay times.