[Goal-directed renal replacement therapy for acute kidney injury after cardiac surgery]

To compare the efficacy and safety of goal-directed renal replacement therapy(GDRRT) and daily high volume hemofiltration (dHVHF) in the treatment of acute kidney injury (AKI) after cardiac surgery.

Clinical data from 128 patients received either GDRRT (n = 64) or dHVHF (n = 64) for AKI after cardiac surgery were analyzed retrospectively. parameters examined included: urea nitrogen, serum creatinine (SCr, before and after treatment), heart rate, mean artery pressure (MAp, recorded within 72 hours after the initiation of renal replacement therapy). The hospital mortality, day-28 mortality, renal function recovery rate, and the incidence of adverse events in the two groups were also compared.

The hospital mortality was 43.75% for both GDRRT and dHVHF treated patients (group). The day-28 mortality in GDRRT group were slightly lower, but the difference was not significant (43.75% vs. 57.81%, P = 0.055). Also no significant difference was found between the two groups in hospital stay. The patients received dHVHF had longer intensive care unit (ICU) stay (hours) and duration of mechanical ventilation (days) as compared to the patients received GDRRT [356.5 (176.3, 554.6) vs. 238.3 (119.6, 440.9), P = 0.023; 8.0 (5.0, 16.0) vs. 6.0 (3.0, 13.5), P = 0.042]. The logistic regression analyses showed that complete renal function recovery rate in GDRRT group was significantly higher (39.1% vs. 18.8%, P < 0.01). The partial renal function recovery rate in GDRRT group was slightly lower but not statistically different from dHVHF group (3.1% vs. 9.4%, P > 0.05). In dHVHF group, the maximum SCr during the treatment, and the SCr before discharge were both significantly higher than GDRRT group (μmol/L: SCr maximum 559.0 ± 236.0 vs. 440.4 ± 192.0, SCr before discharge 381.4 ± 267.0 vs. 271.2 ± 164.4, both P < 0.01). No significant difference was found between the two groups in incidence of hypotension (35.9% vs. 37.5%) and MAP (mm Hg, 1 mm Hg=0.133 kPa, 82 ± 13 vs. 81 ± 15) 72 hours into the therapy (both P > 0.05). The incidence of tachycardia, and incidence of blood coagulation were both higher in dHVHF group (78.1% vs. 59.4%, 35.9% vs. 20.3%, both P < 0.05). However, the hospitalization expense (thousand yuan) was significantly higher for dHVHF group (15.00 ± 2.80 vs. 9.85 ± 3.00, P < 0.01).

For patients with post-cardiac surgery AKI, GDRRT and dHVHF are very similar in terms of short-term survival rate and safety. But GDRRT is superior for renal function recovery and cost saving.