Balanced IV Fluids Can Reduce Kidney Damage and Death in Critically Ill Patients Interview with:

Todd W. Rice, MD, MSc Associate Professor of Medicine Director, Vanderbilt University Hospital Medical Intensive Care Unit Division of Allergy, Pulmonary, and Critical Care Medicine Nashville, TN  

Dr. Rice

Todd W. Rice, MD, MSc
Associate Professor of Medicine
Director, Vanderbilt University Hospital Medical Intensive Care Unit
Division of Allergy, Pulmonary, and Critical Care Medicine
Nashville, TN What is the background for this study?

Response: Our study (called the SMART study) evaluates the effects of different types of intravenous fluids used in practice in critically ill patients.  It is very similar to the companion study (called the SALT-ED study and published in the same issue) which compares the effects of different types of intravenous fluids on non-critically ill patients admitted to the hospital.  Saline is the most commonly used intravenous fluid in critically ill patients.  It contains higher levels of sodium and chloride than are present in the human blood.  Balanced fluids contain levels of sodium and chloride closer to those seen in human blood.

Large observational studies and studies in animals have suggested that the higher sodium and chloride content in saline may cause or worsen damage to the kidney or cause death.  Only a few large studies have been done in humans and the results are a bit inconclusive. What are the main findings? 

Response: Our study (the SMART study), just like the companion study done in hospitalized patients (the SALT-ED study), found that using balanced intravenous fluids led to fewer cases of renal failure and/or death compared to using saline intravenous fluids.  This was true for both patients being cared for in ICUs and in patients being cared for on the regular hospital ward receiving intravenous fluids. What should readers take away from your report? 

Response: Both saline and balanced intravenous fluids are available for use today, at similar cost.  Healthcare providers can decrease the risk of kidney damage or death simply by switching the type of intravenous fluid that they administer to patients in the hospital and ICUs.  Routine use of balanced intravenous fluids is a simple intervention that is readily available and can be incorporated into practice today.  And although the difference of just over 1% in death or kidney damage seems relatively small, millions of patients in the United States receive these intravenous fluids each year.  This means that something as simple as changing the intravenous fluid given to patients to balanced fluids may save tens of thousands of patients from suffering kidney damage or death. What recommendations do you have for future research as a result of this work? 

Response: Future research needs to be done in a number of areas.  First, are there small groups of specific patients where saline happens to be better than balanced fluids, or are balanced fluids better for all hospitalized and critically ill patients?  Second, saline is often the fluid used to administer many medications.  Is it possible to change the way the medicines are prepared so that balanced fluids can be used in giving these medicines instead of saline?  Third, the mechanism (or way through which saline might cause kidney damage or death) is not entirely understood and work needs to be done to understand why or how saline causes kidney damage and/or death. Is there anything else you would like to add?

Response: These studies were conducted as part of the Vanderbilt Learning Healthcare system, which is focused on understanding the effects of different aspects of what is already standard medical care.  This means that the conduct of these studies was truly a collaborative effort between the patients, nurses, nurse practitioners, pharmacists and doctors at Vanderbilt University Medical Center.

Thank you again for the opportunity to discuss our studies.

No disclosures


Balanced Crystalloids versus Saline in Critically Ill Adults
Matthew W. Semler, M.D., Wesley H. Self, M.D., M.P.H., Jonathan P. Wanderer, M.D., Jesse M. Ehrenfeld, M.D., M.P.H., Li Wang, M.S., Daniel W. Byrne, M.S., Joanna L. Stollings, Pharm.D., Avinash B. Kumar, M.D., Christopher G. Hughes, M.D., Antonio Hernandez, M.D., Oscar D. Guillamondegui, M.D., M.P.H., Addison K. May, M.D.,
for the SMART Investigators and the Pragmatic Critical Care Research Group*
March 1, 2018
N Engl J Med 2018; 378:829-839
DOI: 10.1056/NEJMoa1711584

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Last Updated on March 1, 2018 by Marie Benz MD FAAD