Discussion
pneumothorax
COMPLICATIONS, BLIND, COMPLICATIONS, PNEUMOTHORAX
The results of this randomized controlled clinical trial indicate that IPUS-AVP is superior to CVC in terms of success rate, time to venous access, procedure duration, and radiation exposure. Moreover, the rate of complications was not significantly different between the groups (Structured Graphical Abstract).Intra-pocket ultrasound-guided axillary vein puncture is little described in the literatureThe CVC technique was chosen for the control arm because it is the most widely used technique in Europe (first intention for 60% of operators).The success rate of IPUS-AVP alone was 99.0% and the only failure was not related to the vascular access but to the anatomy (persistent left SVC). For comparison, the two randomized trials that investigated US-AVP with a percutaneous technique, by Liccardo In the CVC group, the success rate of CVC route alone was higher than expected, with 86.9% of cases. The level of experience of the operators and the almost systematic use of hydrophilic guidewire account for part of these numbers. The high success rate for CVC observed in this study may also be explained by our definition of success. To reproduce the conditions observed in real-life clinical practice, it was deliberately decided not to set a limit on duration of procedure or the number of attempts to define a failure. It should be pointed out that, although impossibility to blind the operator to treatment allocation could have biased endpoints, especially in the CVC group, success rates and time to obtain venous access are better than those reported in previous randomized trials. In particular for CVC, Chan The cephalic vein is sometimes too small, very tortuous, or even absent, whereas the axillary vein has few anatomical variations and is large enough to accommodate multiple leads.Reduction of time to venous access with IPUS-AVP was expected, as CVC requires time-consuming surgical dissectionOur study also showed a significant reduction in fluoroscopy time and X-ray exposure with IPUS-AVP, again confirmed by the sensitivity analyses performed in those patients successfully managed by a single route. One of the causes of this decrease is the easier insertion of the guidewire in the SVC with IPUS-AVP, without need for fluoroscopy in most cases. Indeed, the path of the cephalic vein is often tortuous, so that fluoroscopy guidance is frequently needed in the CVC technique to navigate the guidewire to the SVC. The reduction in the use of fluoroscopy with IPUS-AVP is also explained by easier lead manipulation and improved stability. Even with relatively low radiation doses, this reduction is an important element of protection against radiation for daily exposed operators. Fluoroscopy usage was not evaluated in the previously mentioned trials.Complications rates were comparable between the two groups. No pneumothorax occurred in our study, which is consistent with previous reports of a low risk of pneumothorax with fluoroscopy- or US-guided AVP.