Correlation between net ultrafiltration intensity of continuous renal replacement therapy and survival prognosis in critically ill patients with acute kidney injury
10.3760/cma.j.cn441217-20240527-00536
- VernacularTitle:连续性肾脏替代治疗净超滤强度与危重症急性肾损伤患者生存预后的相关性
- Author:
Youli TANG
1
;
Lu JIN
1
;
Peiyun LI
1
;
Fang WANG
1
;
Yingying YANG
1
;
Ling ZHANG
1
Author Information
1. 四川大学华西医院肾脏内科 四川大学华西医院肾脏病研究所，成都 610041
- Publication Type:Journal Article
- Keywords:
Continuous renal replacement therapy;
Acute kidney injury;
Mortality;
Net ultrafiltration;
Critical illness
- From:
Chinese Journal of Nephrology
2025;41(9):651-659
- CountryChina
- Language:Chinese
-
Abstract:
Objective:To explore the correlation between the intensity of net ultrafiltration in continuous renal replacement therapy (CRRT) and the survival prognosis in critically ill patients with acute kidney injury (AKI), and provide evidence-based references for establishing optimal net ultrafiltration target during CRRT.Methods:This was a retrospective observational study. Demographic and clinical data of critically ill AKI patients who received CRRT in the Intensive Care Unit of West China Hospital, Sichuan University from May 2021 to September 2023 were collected. Net ultrafiltration was defined as the hourly fluid clearance volume in the 72 hours prior of CRRT. This variable was converted into a categorical variable, including low net ultrafiltration <1.01 ml·kg -1·h -1, moderate net ultrafiltration 1.01-1.38 ml·kg -1·h -1 and high net ultrafiltration >1.38 ml·kg -1·h -1, and the differences of baseline characteristics and clinical treatment conditions among the three groups were compared. Kaplan-Meier survival curve and log-rank test were used to compare the survival conditions among the three groups in patients at 28 days and 60 days after CRRT. Logistic regression analysis method was used to analyze the related factors of mortality in patients 28 days and 60 days after CRRT. Results:This study included a total of 661 critically ill AKI patients who underwent CRRT for more than 72 hours. The age was 56.00 (43.00, 68.00) years, and 488 patients (73.83%) were males. The net ultrafiltration rate was 1.36 (0.94, 1.89) ml·kg -1·h -1. Among them, 188 patients (28.44%) were in the low net ultrafiltration group, 152 patients (23.00%) were in the medium net ultrafiltration group, and 321 patients (48.56%) were in the high net ultrafiltration group. There were statistically significant differences among the three groups in terms of gender distribution ( χ2=17.81, P<0.001), body mass index ( H=32.37, P<0.001), urine volume 24 hours before admission ( H=9.41, P=0.009), fluid overload ( H=6.02, P=0.049), platelets ( H=13.49, P=0.001), pro-B type natriuretic peptide ( H=14.18, P<0.001), serum creatinine ( H=9.66, P=0.008), lactate ( H=9.83, P=0.007), AKI stage distribution ( χ2=15.51, P=0.004), admission indication ( P<0.001), total CRRT duration ( H=8.45, P=0.015), ultrafiltration ( H=456.10, P<0.001), net ultrafiltration ( H=561.20, P<0.001), and vasoactive-inotropic score at 72 hours of CRRT treatment ( H=10.42, P=0.005). Kaplan-Meier survival analysis showed that there were statistically significant differences in the 28-day (Log-rank test, χ2=10.89, P=0.004) and 60-day (Log-rank test, χ2=8.55, P=0.014) survival rates among the three groups in patients after CRRT. Multivariate logistic regression analysis showed age ( OR=1.03, 95% CI 1.02-1.04, P<0.001), mean arterial pressure ( OR=0.98, 95% CI 0.97-1.00, P=0.011), bilirubin ( OR=3.02,95% CI 1.39-5.59, P=0.006), 72-hour vasoactive-inotropic score ( OR=1.01, 95% CI 1.00-1.02, P=0.004), low net ultrafiltration group (medium net ultrafiltration group as a reference, OR=1.66, 95% CI 1.02-2.72, P=0.042), and high net ultrafiltration group (medium net ultrafiltration group as a reference, OR=1.78, 95% CI 1.14-2.78, P=0.011) were independent correlated factors of 28-day mortality after CRRT. Age ( OR=1.02，95% CI 1.01-1.04， P<0.001), mean arterial pressure ( OR=0.98，95% CI 0.97-1.00， P=0.016), fluid overload ( OR=1.10, 95% CI 1.02-1.19, P=0.012), bilirubin ( OR=4.96，95% CI 1.00-17.80， P=0.013), 72-hour vasoactive-inotropic score ( OR=1.02，95% CI 1.01-1.03， P=0.003), and high net ultrafiltration group (medium net ultrafiltration group as a reference, OR=1.91，95% CI 1.22-3.00， P=0.005) were independent correlated factors of 60-day mortality after CRRT. Conclusions:During the first 72 hours of CRRT, net ultrafiltration > 1.38 ml·kg -1·h -1 and net ultrafiltration < 1.01 ml·kg -1·h -1 are associated with a higher mortality rate at 28 days or 60 days after CRRT. Net ultrafiltration of 1.01-1.38 ml·kg -1·h -1 may be a relatively safe range.
