Answer: Yes.
This week, the two heavyweight medical journals, JAMA and
the New England Journal of Medicine, featured papers describing the effect of certain
intravenous fluids on the incidence of renal failure in critically ill ICU patients.
The JAMA paper
compared normal saline (relative to human plasma, a high chloride-containing
solution) administration to more physiologic, low chloride-containing IV fluids
such as Hartmann’s solution (very similar to Ringer’s lactate) or Plasma-Lyte
148. It showed that using the low chloride intravenous infusions led to a
statistically significant decrease in the incidence of acute kidney injury and
the need for renal replacement therapy.
The NEJM paper compared
the use of intravenous hydroxyethyl starch (HES) fluid resuscitation to normal saline and found that patients given HES had significantly more
acute kidney injury and needed more renal replacement therapy. Bear in mind that HES is actually a solution of 6% HES in normal saline.
Neither study found a significant difference in mortality
rates related to the various solutions used.
Both studies were performed in Australia during different
time periods. The JAMA paper was based on research from a single hospital in
Melbourne in 2008-2009 and was a before-and-after trial while the NEJM study
was multi-institutional, randomized and prospective and took place from December
2009 to January 2012.
Is normal saline bad for the kidneys? Yes. If you compare high chloride normal saline to lower chloride
solutions, normal saline causes more renal dysfunction and need for renal replacement therapy. Normal saline vs.
HES really compared normal saline alone to 6%
starch in normal saline, and showed that the starch is probably the factor causing
renal injury.
So what is a clinician to do? Normal saline is not really “normal.” Solutions
containing amounts of chloride closer to that of human plasma are the correct
ones to use. As we surgeons have maintained all along, Ringer’s lactate should
be the resuscitation fluid of choice in the U.S.
See the table below for the amounts of sodium, chloride and buffer in standard IV solutions.
