Ms Shalini Elangovan1, Professor Brett Mitchell2, Professor Nicholas Graves1
1Duke-NUS Medical School, Singapore, Singapore, 2Avondale University, Cooranbong, Singapore
Biography:
Ms Shalini is a 4th year PhD student at the Duke-NUS Medical School in Singapore. Her thesis focuses on the use of economic evidence in infection prevention and control decision-making.
Abstract:
Catheter-related bloodstream infections (CRBSI) are associated with longer hospital stays and increased mortality risks. The RSVP trial was a multi-centre randomized controlled study that found central venous access devices and peripheral arterial catheters infusion set replacement intervals can be safely extended from 4 to 7 days without increasing CRBSI risk. Equivalence of CRBSI for both replacement intervals was defined as a risk difference within 2%. The study concluded that large costs would be saved, with health benefits unchanged. Cost-effectiveness of adoption was assumed but not demonstrated.
This study evaluates the cost-effectiveness of adopting the 7-day replacement protocol compared to the standard 4-day interval via decision-analytic modelling.
A decision tree model was developed from a healthcare perspective, incorporating data from the RSVP trial and evidence from a prior systematic review. Relevant costs were included. Effectiveness outcomes considered the life years gained from avoiding mortality specific to gram-negative and gram-positive CRBSI, which were discounted at a rate of 3%. A probabilistic sensitivity analysis was conducted to generate a joint distribution of cost and effectiveness outcomes.
The probability of a 7-day compared to 4-day replacement protocol being cost-effective at a willingness-to-pay threshold of AUD$28,300 is 53%. Additionally, there is a 79% probability of cost-savings. Health benefits were likely to be reduced with an additional 401 cases of CRBSI, 104 deaths, and 1749 life years lost across the same population. We conclude that there is weak evidence supporting cost-effectiveness of adopting a 7-day infusion set replacement interval for CVADs and PACs.