1. Stepwise changes in positive end expiratory pressure (PEEP) were not associated with clinically significant changes in subclavian vein (SCV) and parietal pleura distance (DVP), or SCV cross-sectional area (CSA), factors that impact the optimization of SCV cannulation.
Evidence Rating Level: 2 (Good)
When considering cannulation of the subclavian vein (SCV), the utility of positive end expiratory pressure (PEEP) is unclear. For instance, PEEP could increase the risk of pneumothorax from this procedure, secondary to decreasing the parietal pleura and SCV distance (DVP). However, PEEP could also increase the SCV cross-sectional area (CSA), improving the success rate. Therefore, this single-centre prospective study evaluated the effects of varying PEEP levels on DVP and CSA. This study enrolled 27 adults who had underwent invasive mechanical ventilation, with a clinical indication for stepwise trials of PEEP. The DVP and CSA were measured bilaterally using ultrasound examination of the SCV at 0, 5, 10, and 15 cm H2O of PEEP. A clinically relevant change was considered to be >2 mm for DVP and >2mm2 for CSA. The results showed a statistically and clinically significant increase in the CSA on the right side at a PEEP of 10 compared to 0 (difference 2.5). There was also a statistically significant increase in DVP at PEEP of 15 compared to 0, with the in-plane ultrasound view on the left side (difference 0.7, p = 0.048). Otherwise, there were no statistically or clinically significant differences in DVP or CSA at varying PEEP levels in this study. Overall, this demonstrated that stepwise changes in PEEP do not generally affect factors impacting the optimization of SCV cannulation, such as DVP and CSA.
Click to read the study in PLOS
Image: PD
©2023 2 Minute Medicine, Inc. All rights reserved. No works may be reproduced without expressed written consent from 2 Minute Medicine, Inc. Inquire about licensing here. No article should be construed as medical advice and is not intended as such by the authors or by 2 Minute Medicine, Inc.
