The 3 Stations of the Needle: A systematic approach for ultrasound guided venous and arterial puncture

Point-of-care ultrasound-guided (POCUS) venous and arterial access involves accurately guiding a needle from the skin surface through subcutaneous tissue to the target vessel. The success of this procedure relies heavily on the operator's ability to locate and direct the needle tip, which can lead to multiple puncture attempts and iatrogenic complications. A literature review revealed a lack of comprehensive protocols addressing the sonographic details necessary for effective needle identification and vessel cannulation. This paper presents a systematic approach, the "3 Stations of the Needle" protocol, which includes: (1) identifying the needle after initial skin puncture within the subcutaneous tissue; (2) navigating the needle to the vessel's outer wall; and (3) advancing the needle tip into the vessel lumen. This protocol offers a practical educational method for an ultrasound mastery learning program, enhancing needle identification, guidance, safety, and procedural success in venous and arterial cannulation.