Impact of Double-Machine Replacement Protocol at Start of Continuous Renal Replacement Therapy in Vasopressor-Dependent Patients: A Retrospective Cohort Study

When starting continuous renal replacement therapy (CRRT), vasopressor-dependent patients are at risk of hemodynamic instability. Thus far, only a few studies have analyzed the impact of CRRT circuit replacement for vasopressor-dependent patients. Hence, we compared the effect of double-machine replacement protocol (DMRP) with single-machine replacement protocol (SMRP) for CRRT circuit replacement in vasopressor-dependent patients.The medical records of 96 vasopressor-dependent patients treated with CRRT in the general intensive care unit of the Shunde Hospital, Southern Medical University, between January 2017 and April 2018 were retrospectively analyzed. The major measures of the SMRP included returning the blood to the patient and sealing access catheter with heparin and starting a new CRRT machine with a slow blood pump, while DMRP involved simultaneous drawing and return of blood with two machines using a slow blood pump for circuit replacement. The primary outcome measures were changes in vasopressor dose and hemodynamic parameters, and the secondary outcome measure was the pause time difference between the two groups during the period.A total of 53 patients were treated with SMRP and 43 patients with DMRP. Heart rate was higher in the SMRP group as compared to the DMRP group (p < 0.05). There were no significant changes in central venous pressure, mean arterial pressure, and vasopressor dose in either group (p > 0.05). The patients in the DMRP group had a significant reduction in CRRT pause time (5.62 ± 0.69 min in DMRP group vs. 37.01 ± 8.72 min in SMRP group, p < 0.01). The DMRP group needed a lower volume of circuit purging and priming fluid related to CRRT circuit replacement (0 mL in DMRP group vs. 463 mL in SMRP group).Implementation of the DMRP for CRRT circuit replacement had a slight hemodynamic effect on vasopressor-dependent patients. It also reduced the pause time and volume of circuit purging and priming fluid related to CRRT circuit replacement compared with SMRP.