Ultrasound guided central venous access; a review of literature

Central venous access is still the standard of care in critically ill patients despite several controversies. Ultrasound guided central venous access is now considered to be the standard of care practice due to its better safety and accuracy profile. Ultrasound guidance not only reduces the number of attempts but also the associated complications reported for landmark technique. Adequate training is mandatory to achieve desired results, but the learning curve is highly variable from person to person. It is recommended that at least 10 supervised ultrasound-guided vascular access procedures must be done by a physician to show competency. Two techniques are suggested for central venous cannulation, static or prescan technique and real time or dynamic technique. The vessel can be targeted in short axis or in long axis plane. Linear transducers with higher frequencies between 7.5 and 12 MHz are preferred for vascular access procedures. To remember the procedure steps, a mnemonic abbreviated as 4P's is suggested which indicate prescanning, preparation of patient and probe, poke in and path identification. Sterility must be observed during the ultrasound guided central venous access. Appropriate documentation is an essential part of the procedure. Real-time ultrasound guidance for cannulation of the IJV is supported by current literature. It has managed to reduce the complications associated with central line insertion and clearly improves the success rate.