Discuss the use of hypertonic saline in the treatment of intra-cranial hypertension following head injury.
• The effect is rapid, peaking at 10 minutes and waning after 1 hour.
• End point for therapy is serum Na between 145-155 and easily achieved in ICU through blood gas machines.
• Less potential for hypovolemia than with mannitol.
• May have a better effect on CBF for a given reduction in ICP.
• Theoretical benefit in modulating the inflammatory response
• HS is inexpensive
• Need for a central venous access .
• "Hypokalaemia and hyperchloraemic acidosis
• Lack of outcome data,
• Increase in circulating volume and risk of CCF.
• Coagulopathy-HS may affect APTT and INR as well as platelet aggregation.
• Rapid changes in serum sodium concentrations may result in seizures and encephalopathy
• Some suggest that HS affects normal brain more that injured brain which theoretically may worsen herniation
The use of hypertonic saline in the treatment of raised intracranial pressure falls within the realm of osmotherapy, which enjoys a thorough discussion elsewhere:
- Intracranial pressure as a therapeutic target
- Management of raised intracranial pressure
- Osmotherapy for management of raised intracranial pressure
From those summary, a table of comparison can be compiled, which is presented below.
Chapter 43 (pp. 563) Cerebral protection by Victoria Heaviside and Michelle Hayes, and
Chapter 67 (pp. 765) Severe head injury by John A Myburgh.
Francony, Gilles, et al. "Equimolar doses of mannitol and hypertonic saline in the treatment of increased intracranial pressure*." Critical care medicine 36.3 (2008): 795-800.
Kamel, Hooman, et al. "Hypertonic saline versus mannitol for the treatment of elevated intracranial pressure: A meta-analysis of randomized clinical trials*."Critical care medicine 39.3 (2011): 554-559.
Nau, Roland. "Osmotherapy for elevated intracranial pressure." Clinical pharmacokinetics 38.1 (2000): 23-40.
Rickard, A. C., et al. "Salt or sugar for your injured brain? A meta-analysis of randomised controlled trials of mannitol versus hypertonic sodium solutions to manage raised intracranial pressure in traumatic brain injury." Emergency Medicine Journal (2013).
Lazaridis, Christos, et al. "High-Osmolarity Saline in Neurocritical Care: Systematic Review and Meta-Analysis*." Critical care medicine 41.5 (2013): 1353-1360.
Bhardwaj, Anish, and John A. Ulatowski. "Hypertonic saline solutions in brain injury." Current opinion in critical care 10.2 (2004): 126-131.
Arbabi, Saman, et al. "Hypertonic saline induces prostacyclin production via extracellular signal-regulated kinase (ERK) activation." Journal of Surgical Research 83.2 (1999): 141-146.
R LAWRENCE REED, I. I., et al. "Hypertonic saline alters plasma clotting times and platelet aggregation." Journal of Trauma-Injury, Infection, and Critical Care 31.1 (1991): 8-14.