Comparing traditional Placement With placement using electrocArdiography for central Vascular access dEvices trial (P Wave Trial)

This was a pragmatic, open-label randomised controlled trial comparing accuracy, timing and cost between anthropometric and intracavitary electrocardiography (IC ECG) guided CVAD insertion. Recruitment commenced 13th of December 2016 and completed 4th July 2018 with all patient follow completed by 10th September 2018. Ethical approval to commence this study was given by the South Western Sydney Local Health District Human Research Ethics Committee (HREC/15/LPOOL/552). CVAD insertion was performed by accredited nurses in both groups as a once off procedure (approximately 12 minutes). Maximal sterile technique with the use of ultrasound was used to gain venous access and to scan vessels during the procedure for suspected malposition. In the intervention group a portable, wireless IC-ECG navigation system (Nautilus Delta Tip Confirmation System– BARD Access Systems, Salt Lake City USA) was used to monitor changing R wave progression as well as increasing amplitude of the P wave to confirm position. When maximum P wave amplitude was achieved, the catheter tip was deemed to be located at the cavo-atrial junction (CAJ) or upper RA and the CVAD was then secured and dressed. This particular IC-ECG read out device was already established and has been used across hospitals in Europe. Training for users was provided by a local distributor and incorporated a blended learning approach with web based material and practical demonstration. Safety monitoring for this study was undertaken using local organisational governance procedures (documenting, escalating and reviewing any procedural or latent complications). Due to the low risk nature of the trial, no stopping rules were implemented as part of the study protocol. In both groups, a chest x ray (CXR) was administered post catheter insertion to confirm final catheter tip position. A single radiologist, (blinded to study group) with extensive experience in CXR film interpretation, reviewed all CXRs to confirm catheter tip position using digital calipers and the tracheal carina as a measuring landmark on the computerised film. Care and maintenance of devices in both groups was based on current hospital guidelines and was not distinguished. An independent observer documented the procedural time start time (first needle puncture of skin) and conclusion time (the sterile dressing was applied). Procedure room set up and clean up time was not included in timings. Although post procedure CXRs were performed in both groups, total procedure time was measured in the IC ECG group when sterile dressing was applied to skin, since this is when the catheter would normally be released for use after ECG confirmation. If catheters required repositioning after CXR in either group, time was measured for this additional procedure and added to the total procedure time.