Abstract
This study aimed to compare a high (HBF) and low (LBF) bicarbonate (HCO
) replacement fluid over 96 h after continuous veno-venous hemofiltration (CVVH) initiation using regional citrate anticoagulation to determine which fluid achieved better acid-base balance.
In this prospective, randomized, controlled, open-label, cross-over, single-center trial, patients were randomized to initially receive either LBF (22 mmol/l HCO
) or HBF (30 mmol/l HCO
) for 48 h (first phase), followed by changing to the other fluid for a further 48 h (second phase). Intracorporeal pH and HCO
changes were analyzed by calculating the rates of levels outside the standard values (excursion rates). Generalized estimating equations were performed to estimate the odds ratios for at least one pH/HCO
excursion. Time to normalization within the first phase for pH and HCO
was assessed using Kaplan-Meier curves and log-rank tests.
A total of 88 patients were included. The rates for at least one pH and HCO
excursion were higher in patients treated with HBF compared to LBF (pH: first phase 52% vs. 41%; second phase 48% vs. 34%; HCO
: first phase 68% vs. 43%; second phase 73% vs. 43%). Adjusted odds ratios were 1.78 (95% CI 1.12-2.82; p = 0.015) for pH and 3.60 (95% CI 2.16-5.99; p < 0.001) for HCO
. The time to normalization of pH in acidotic patients and of HCO
in patients with low HCO
did not differ significantly between HBF and LBF (p = 0.102, p = 0.468).
LBF showed significantly lower rates of pH and HCO
excursions compared to HBF and no significant differences to the pH normalization in acidotic patients were observed.
NCT04071171.