LR vs NS Journal Club
St. Luke’s ED, March 2015
|mEq/L or mOsm||BODY||NS||LR|
* (we’re used to 8.5-10.3 mg/dL units)
So NS is basically a 50 mEQ chloride infusion per L.
Severes in Nephrology, Dialysis & Transplant Review (2014)
Review article. Limited data suggestive.
“Documented negative safety profile of NS relatively persistent across multiple studies.”
NS causes acidosis
- In one surg RCT, 7.28 vs 7.41
- Likely worsens coagulation, as surgery RCTs show increased need for blood
NS associated with renal failure
- Causes renal vasoconstriction, decreased GFR & decreased UOP
- An LR-like sol'n caused double UOP in first 6 hours vs NS
- A 5-fold increase in one study for needing dialysis
- NS a/w hyperK vs LR, even though LR *contains* some K+
McCluskey, Anesthesia & Analgesia, 2014
Cohort study of 22,851 surgical patients.
Hyperchloremia in 1 of 5 post-surgery patients
Hyperchloremia had increased 30-day mortality (OR 2) and longer stays by 1 day
Can you track lactate levels while giving a lactate-containing IV fluid like LR? Yes.
Seems like if a normal lactate is 1 mEq/L it should increase lactate levels to give a L with 28 mEq! But it does not. Massive amounts of lactate are being metabolized at all times, and the rise in lactate in ill patients reflects imbalance / homeostasis failure.
Can you give blood or Ceftriaxone with LR?
a) Pharmacy will say “not proven compatible” with some abx (Ceftriaxone). Never shown to be a problem, it’s a theoretical.
b) Guidelines for transfusions insist that only NS can be given with pRBCs.
Concern, again, is that LR contains Ca++ which “might activate clotting.” (No evidence of this. Contains less Ca++ than blood itself)