Author + information
- Deep Sharma, MD⁎ ()
- ↵⁎Department of Nephrology, Albert Einstein College of Medicine/Montefiore Medical Center, Ullmann Building Room 615, 1300 Morris Park Avenue, Bronx, New York 10461
Marenzi et al. (1) recently reported the results on a single-center, prospective, randomized, nonblinded trial to investigate the role of combined furosemide-induced high-volume diuresis and automated matched hydration (intervention group), combined with standard saline hydration (control group), for the prevention of contrast-induced nephropathy (CIN) in chronic kidney disease patients undergoing coronary procedures.
However, it is worth noting that the 2 study groups were different with respect to the fluids infused. In the intervention group during the 6 ± 1 h of treatment, the volume of saline hydration was 3,995 ± 1,401 ml. Urine output was matched to the infusion rate (minus the 250-ml fluid bolus received as specified in the protocol). The intervention group thus had a net positive fluid balance. In the control group, during the 25 ± 2-h treatment period, the cumulative saline hydration was 1,742 ± 290 ml. Importantly, however, urine output during hydration in the control group was 3,117 ± 876 ml. Thus, the control group had a net negative fluid balance. The reason for this finding is not entirely clear. It is possible that continuing the diuretics that both groups of patients were on as outpatients caused this finding. Forty-eight of 83 (58%) of patients in the control group were on diuretics, and there was no protocol to stop these medications before the intervention. Thus, the differences in the fluid administered and the fluid balance achieved likely influenced the results of the study in the 2 groups.
Majumdar et al. (2) in their meta-analysis comparing furosemide-based intervention with saline hydration for the prevention of CIN concluded furosemide-based interventions to be detrimental to saline hydration for the prevention of CIN. However, the studies that were analyzed did not have as rigorous a method of hydration in the intervention arms as did the study by Marenzi et al. (1).
In light of prior randomized controlled trials, to demonstrate benefit of furosemide-based intervention with hydration over saline hydration alone for the prevention of CIN, it is critical to keep both study arms equally hydrated. Failure to do so may influence the results of the study. Thus, studies maintaining equal hydration in both groups are needed to demonstrate a difference in outcome due to the intervention.
- American College of Cardiology Foundation
- Marenzi G.,
- Ferrari C.,
- Marana I.,
- et al.
- Majumdar S.R.,
- Kjellstrand C.M.,
- Tymchak W.J.,
- Hervas-Malo M.,
- Taylor D.A.,
- Teo K.K.