While Lactated Ringers (LR) contains sodium lactate, this lactate is metabolized by the body and does not contribute to or worsen lactic acidosis. In fact, the acidosis associated with normal saline (NS) may have more clinically harmful effects. Isotonic fluids like LR, NS, and plasmalyte maintain an osmolality near that of plasma (280-290 mOsm/L) and are preferred for fluid therapy in neurosurgery patients to prevent decreases in plasma osmolality and cerebral edema.

1. Myth – “Lactated Ringers causes lactic acidosis, and therefore should be
avoided.”
Lactic acidosis is a result of failed oxidative metabolism, leading to an anion-gap
metabolic acidosis. This can be secondary to decreased metabolism of naturally
generated lactate in the body (such as in liver disease) or increased production of
lactate when there is decreased oxygen available for aerobic metabolism. The most
common etiologies of lactic acidosis in the ED are from sepsis, trauma, and
dehydration. While less common, there can also be iatrogenic causes of type B lactic
acidosis secondary to beta agonist administration, such as epinephrine or albuterol.
There is speculation that the lactate concentration in LR (28 mEq/L) compared to
NS (0 mEq/L) and human plasma (1-2 mEq/L) may worsen lactic acidosis. In reality,
this lactate is in the form of sodium lactate which our bodies metabolize to products
that prevent cellular death. It is not the same lactate that is generated during
anaerobic metabolism, which causes metabolic acidosis.
It is theorized that the lactate infused in the LR group may be metabolized under
ischemic conditions and decrease overall cell death and is less likely to worsen an
acidosis when compared to the hyperchloremic acidosis that results from NS.
Pearl: Though LR contains sodium lactate, this is generally metabolized by the
body and does not contribute to worsening lactic acidosis. In fact, the acidosis
associated with NS likely has more clinically harmful effects.
For most patients with acute stroke and volume depletion, isotonic saline
without dextrose is the agent of choice for intravascular fluid repletion and
maintenance fluid therapy. It is best to avoid excess free water (e.g. 1/2 isotonic
saline). • Hypotonic fluids may exacerbate cerebral edema in acute stroke.
Administration of 0.9% NaCl 100 ml/h for 72 h in patients with acute ischemic
stroke is safe and may be associated with a reduced risk of neurological
deterioration. These study findings support the use of intravenous fluid in acute
ischemic stroke patients with NIHSS less than 18 who have no
contraindications.
Cairan isotonis adalah carian yang mengandung osmolalitas yang mendekati
osmolalitas plasma yaitu 280-290 mOsm/Ldimana meliputi ringer laktat, NaCl
0.9%, dan asering.
The general principle of fluid therapy for neurosurgery is to maintain normal
blood volume and prevent a decrease in plasma osmolarity. In a normal blood-
brain barrier (BBB), the movement of water between the plasma and brain is
mainly influenced by the osmotic gradient. Therefore, in neurosurgery, the
osmolarity of the fluid is the most important factor to prevent cerebral edema.
A crystalloid fluid contains small molecular substances without high molecular
substances, and it is classified as hypotonic, isotonic, or hypertonic according
to its osmolarity. Lactated Ringer's solution (LR), a commonly used crystalloid,
is hypotonic at 273 mOsm/L. Low plasma osmolarity can cause cerebral edema.
Therefore, hypotonic solutions, such as LR, are avoided, while normal saline
(NS) has traditionally been used as the main fluid in patients with neurosurgery