What should the nurse do first after inserting an over-the-needle catheter into a vein?

After inserting an over-the-needle catheter into a vein, the primary action is to check for blood return in the flashback chamber. This is a critical step because it confirms that the catheter is correctly positioned within the vein. When blood enters the flashback chamber, it indicates that the catheter is patent and that the venous access has been successfully obtained. This confirmation is essential before proceeding further since it ensures the effectiveness of the venous access and minimizes the risk of complications related to incorrect placement.

Other actions, such as securing the catheter with tape, flushing the catheter with normal saline, or documenting the insertion site, are important steps in the overall process of IV therapy. However, these should be conducted only after verifying the proper placement of the catheter. If the catheter is not correctly positioned, subsequent actions like flushing or securing it could result in complications, such as infiltrations or extravasation. Therefore, checking for blood return in the flashback chamber is the most crucial first step following catheter insertion.