Background and Goal of Study:
The majority of UK Critical Care Units use the distal lumen for central venous pressure monitoring (CVPM) (1). As previously discussed, this poses an increased risk in the event of central venous catheter (CVC) displacement (1). Although there may be differences in measurement, there is limited evidence to suggest any particular lumen is superior to others for CVPM (2). There has been a suggestion that the proximal lumen offers an added measure of safety and should be the lumen of choice for CVPM (1,3). The aim of
this audit was to measure compliance of CVPM using the proximal lumen in critical care units of NHSAyrshire & Arran.

Materials and Methods:
We prospectively performed daily checks on each CVC within the ICU at University Hospital Crosshouse (UHCH) and the ICU and HDU at University Hospital Ayr (UHA), encompassing all critical care units of NHS Ayrshire & Arran. The lumen being used for CVPM were documented. Data was collected between November 2016 – February 2017 at UHCH, and between August 2017 – November 2017 at UHA.

Results and Discussion:
A total of 181 daily CVC checks were performed; 131 at UHCH and 50 at UHA. Proximal lumen were used only 60% of the time (66.4% at UHCH, 44% at UHA respectively). We identified this as a significant safety risk and changes are currently being implemented.

Conclusion(s):
CVC displacement can lead to complications and death (1). The use of proximal lumen for CVPM can reduce unnecessary risk to the patient. Despite concern, many units throughout the UK, including our own, continue to use the distal or medial lumen for CVPM. We expect the implemented changes will lead to greater compliance with using the proximal lumen for CVPM.

References (optional):
1. K. Lake, C. Barker, P. Jefferson, DR Ball. Correspondence/response to: Monitoring central venous pressure: proximal or distal lumen: a safety issue. Anaesthesia 2011; 66: 318 - 319
2. Scott SS, Giuliano KK, Pysznik E, et al. Influence of port site on central venous pressure measurements from triple-lumen catheters in critically ill adults. Am J Crit Care. 1995;7:60-63
3. Alsafi A, Pahamin T, Selvaraj I, Woollard C. Monitoring of central venous pressure via the proximal lumen: a safety issue. Anaesthesia 2010; 65: 1241.

05 / Measuring Central Venous Pressure Using the Proximal Lumen: An Audit