OR20-1 Impact of Intra-Procedural Sedation on Outcomes of Adrenal Vein Sampling

BACKGROUND: The subtyping of primary aldosteronism (PA) requires interpretation of aldosterone and cortisol concentrations measured during adrenal vein sampling (AVS). The use of intravenous sedation during AVS is not standardized but may affect AVS outcomes. PURPOSE: To characterize the impact of sedation on the outcomes of AVS, including cortisol and aldosterone concentrations, cannulation success and rates of lateralisation. MATERIALS AND METHODS: This is a retrospective cohort study based at a tertiary health centre. Consecutive patients who underwent AVS both before and after ACTH stimulation between June 2018 and July 2020 were included. AVS was performed without IV sedation in patient cohort 1 (n = 70), with sedation (midazolam and fentanyl) in cohort 2 (n = 34) and both before and after sedation in cohort 3 (n = 14). Comparisons were performed using the nonparametric (Mann Whitney U) test for continuous variables and the Chi square test for categorical variables. RESULTS: Overall, 118 patients (median age, 53 years; 67 men) were evaluated with no significant demographic differences between the three cohorts. Compared to cohort 1, patients in cohort 2 displayed significantly lower cortisol concentrations in the peripheral vein (median of 141 nmol/L vs 218 nmol/L), left adrenal vein (522 nmol/L vs 1284 nmol/L) and right adrenal vein (577 nmol/L vs 1578 nmol/L) in unstimulated AVS. Fewer patients were assessed to have successful right sided cannulation in cohort 2 (79% vs 93% in cohort 1, p = 0.047). In cohort 3, cortisol concentrations were markedly lower after sedation, with the decrease being more marked in the adrenal veins compared to peripheral veins, hence leading to lower selectivity indices. There were no clinically significant changes in aldosterone concentration or rates of lateralisation after sedation. CONCLUSIONS: IV sedation reduces cortisol concentrations during unstimulated-AVS, leading to lower selectivity indices and fewer cannulations judged as successful. Importantly, radiologists are turning to point-of-care rapid cortisol tests to determine if the catheter is 'in' the adrenal vein in real-time. Adrenal vein samples collected after sedation are more likely to be considered "unsuccessful" using these semi-quantitative assays. The need for IV sedation during AVS should be carefully assessed. Presentation: Monday, June 13, 2022 11:00 a.m. - 11:15 a.m.