Spark Study: Does Low Dose Lasix Provide Kidney Protection in AKI? Interview with:
Sean Bagshaw MD MSc
Director for Research for the Division of Critical Care Medicine
School of Public Health
University of Alberta, Canada What is the background for this study? What are the main findings?

Response: The rationale for SPARK stemmed from two general observations.

First, experimental and pre-clinical data have suggested the timely utilization of loop diuretics in early AKI could provide “kidney protection” largely mediated through reduction in medullary oxygen demand. Yet, this is in apparent paradox with clinical data (largely derived from older observational studies at some risk of bias) suggesting use of loop diuretics in AKI may be associated with increased risk for death and/or non-recovery of kidney function.

Second, in AKI, loop diuretics are used exceedingly often. Surveys of healthcare practitioners and observational data suggest more than two-thirds to three-quarters of patients are exposed to diuretics at some point during their course. This represents a significant misalignment between evidence and clinical practice. This would suggest there is need to generate new evidence and knowledge that would ideally help inform best practice in the management of AKI.

SPARK was designed as a pilot trial largely aimed at evaluating the feasibility of the approach to use of loop diuretics in early AKI. While SPARK did not find significant differences in risk of worsening AKI, utilization of RRT or mortality, we recognize the trial was underpowered to meaningfully inform about these and other patient-centered outcomes. We did see differences in secondary endpoints (i.e., fluid balance); however, use of loop diuretics in this setting was also associated with greater incidence of electrolyte abnormalities. What should readers take away from your report?

Response: Our trial at best would suggest there was no evidence of improvement in clinical endpoints associated with low-dose furosemide in early AKI infusion (though there was no trend to suggest worse clinical outcome); however, the protocol was challenging and translated into greater adverse effects largely driven by minor electrolyte abnormalities. What recommendations do you have for future research as a result of this study?

Response: SPARK had a protocol that proved quite challenging to implement. As a consequence, we do not currently have plans to perform a larger definitive study with this approach.  However, we strongly believe, given the apparent misalignment in evidence and practice, that additional studies needs to focus on the optional population, settings and conditions for loop diuretic use in AKI. Is there anything else you would like to add?

Response: The trial was funded by a grant from Alberta Innovates – Health Solutions and a seed grant provided by the members of the Department of Critical Care Medicine, Faculty of Medicine and Dentistry at the University of Alberta. The authors do not have any relevant disclosures with respect to the SPARK study to declare. Thank you for your contribution to the community.


Spark Study – Low-Dose Furosemide in Critically Ill Patients with Early Acute Kidney Injury: A Pilot Randomized Controlled Trial

American Journal of Kidney Diseases , Volume 69 , Issue 5 , A2

Note: Content is Not intended as medical advice. Please consult your health care provider regarding your specific medical condition and questions.

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Last Updated on April 29, 2017 by Marie Benz MD FAAD