ASSOCIATION OF VASOPRESSOR USE DURING RENAL REPLACEMENT THERAPY AND MORTALITY IN ACUTE KIDNEY INJURY

Introduction:

Among critically ill patients with severe acute kidney injury (AKI), renal replacement therapy (RRT) may contribute to hemodynamic instability and vasopressor use. However, the association of vasopressor use on clinical outcomes after RRT initiation is unknown.

Methods:

We conducted an analysis of adult critically ill patients who had AKI and required RRT in U.S. hospitals. We extracted data from the Premier PINC AI Healthcare Database on vasopressor use 3 days before and after initiating RRT from January 1, 2018, to June 30, 2021. Cox regression was utilized to analyze how using vasopressors affected hospital mortality by day 90 while adjusting for demographics, comorbidities, acuity of illness, IV fluid use and ICU care processes. The analysis found a significant interaction between RRT modality and vasopressor use on mortality. Consequently, the final analysis was stratified by initial RRT modality.

Results:

A total of 20,882 patients with AKI treated with RRT were analyzed. The average age was 63 years, with 38% women and 37% receiving initial treatment with CRRT. A total of 72% received vasopressors, 16% before the initiation of RRT, 21% after the initiation of RRT, and 35% both before and after RRT. Additionally, 77% of CRRT patients and 44% of IHD patients received vasopressors after the initiation of RRT (Fig. 1). A lower 90-day survival rate was observed in patients who received vasopressors after starting RRT (21%, 95% CI: 19%-24%) compared with those who did not receive vasopressors (39%, 95% CI: 34%-45%; p<0.001; Fig. 2). After stratifying by RRT modality and adjusting for age, sex, race, surgical admission, COVID-19, septic shock, ECMO, mechanical ventilation, and days in the ICU before RRT initiation, the number of vasopressors used after RRT was found to be independently associated with hospital mortality for both RRT modalities (CRRT, 1 vasopressor: aHR 1.50, 95%CI: 1.36-1.65; 2 vasopressors: aHR 1.94, 95%CI: 1.76-2.14; 3+ vasopressors: aHR 2.06, 95%CI: 1.72-2.46; IHD, 1 vasopressor: aHR 1.58, 95%CI: 1.47-1.69; 2 vasopressors: aHR 2.21, 95%CI: 2.02-2.42; 3+ vasopressors: aHR 2.30, 95%CI: 1.81-2.94). Average daily IV fluid use also was independently associated with hospital mortality for both RRT modalities (CRRT, middle tertile: HR 1.10, 95%CI: 1.01-1.21; top tertile: HR 1.17, 95%CI:1.07-1.27; IHD, middle tertile: HR 1.15, 95%CI: 1.07-1.23; top tertile: HR 1.12, 95%CI: 1.04-1.21). There was no interaction between the use of vasopressors and IV fluids on mortality.

Conclusions:

Vasopressor and IV fluid use after starting RRT were independently associated with higher risk-adjusted hospital mortality in CRRT and IHD patients. The risk was incrementally higher in patients receiving multiple vasopressors post-RRT initiation.

I have potential conflict of interest to disclose.
This study was funded by Baxter Healthcare Corporation. However, the Authors retain full responsibility for its content. RM and JAN received consultant fees from Baxter for this study. JE, KH, CP, and DBL are full-time employees of Baxter International with ownership interests.

I did not use generative AI and AI-assisted technologies in the writing process.