Hypertonic Saline for TBI

Hypertonic Saline

There has been a lot of focus on the appropriate evaluation of pediatric MINOR head injury (we’ve even covered the 3 month old caveat and concussions); however, let us not forget that MAJOR head injury is a serious public health problem in pediatrics.  Knowing what needs to be done when caring for these patients can actually not only save a live, but help improve the neurologic outcome.  So the question is not which kid with major head injury needs a CT (they all do); the question is, who needs Hypertonic Saline?

 

Pediatric TBI

  • CDC estimates that 7,440 deaths / year in kids <19yrs.
  • Likely equates to ~35,000 kids suffering from severe TBI each year! (based on ~20% mortality rate).
  • HUGE quality of life and monetary cost to the population.
  • While the potential for disaster is great, the possibility for a tremendous save is present… so be diligent and vigilant!

 

Don’t forget the Basics!!

We often become fixated on the next step or therapy, but let’s not let the basics go unappreciated as they can lead to significant consequences if not done correctly.

  • A primary goal throughout resuscitation needs to be to Prevent Hypotension and Hypoxemia.
    • Both will worsen secondary brain injury.
    • RSI with C-Spine stabilization should be done early.
    • Get access! Give fluids. Stop Bleeding.
  • Consider Head Positioning
    • Head of Bed at 30 degrees will aid in venous drainage.
    • Ensure head is Midline to ensure one side’s venous flow is not being constricted.
  • Make the patient sedated and paralyzed!
    • The patient fighting against bagged respirations will likely increased ICP.
    • Agitation, anxiety and stress will all exacerbate the problem.
    • Be mindful, though, of inducing hypotension.
      • Consider Etomidate if lower BPs
      • Thiopental is an alternative for patients who have higher BPs.
  • Many will choose to use Lidocaine as a pretreatment medication for RSI.
    • Good idea… but really needs to be given several minutes before intubation.
    • If you have time to use it, feel free to.  If you don’t, don’t waste time waiting for it. {that’s my 2 cents}

Signs of Badness / Herniation

  • Cushing’s Triad (Bradycardia, Hypertension, Irregular Respirations)
  • Unequal Pupils
  • Lateralizing extremity findings
  • Posturing

If you are seeing these issues… then it is not only time to call the Neurosurgeon but it is also time to give Hypertonic Saline!

Hypertonic Saline

  • Hypertonic saline has been used since 1919 for ICP reduction.
  • The Blood Brain Barrier is essentially impermeable to sodium (as well as mannitol).
    • Hypertonic saline will exert an osmotic effect on the brain and help shift fluid out of the confined cranial vault.
    • Other theoretical benefits include:
      • Restoration of normal cellular resting membrane potentials and cell volume,
      • Stimulation of arterial natriutetic peptide release,
      • Inhibition of inflammation,
      • Increased cardiac output.
  • Hypertonic Saline can be used in patients with hemodynamical instability as it can preserve intravascular volume.
  • In 2012, the updated guidelines for the acute medical management of severe traumatic brain injury in kids were published.

    • Unfortunately, even after digging through all of the available literature, no Level I Recommendations (“Must be done” therapies) could be made.
    • Several Level II Recs (“Should be considered”) were made though.
      • Hypertonic Saline should be considered for the treatment of severe pediatric traumatic brain injury (TBI) associated with intracranial hypertension.
  • Effective doses for acute use range between 6.5 and 10 ml/kg.

What about Mannitol?

  • Still a good drug… but the guidelines could not comment on it as there are no studies of Mannitol that met the inclusion criteria.
  • It has been used a long time and has a good clinical record.
  • Mannitol works by:
  1. Reducing blood viscosity
    1. Rapid effect, but transient (< 75 min)
    2. Leads to reflexive vasoconstriction which allows cerebral blood flow to be maintained despite a reduced level of cerebral blood flow.
    3. Both cerebral blood volume AND ICP decrease.
  2. Osmotic effect
    1. Develops more slowly (15-30 min).
    2. Effect lasts up to 6 hrs.
    3. May actually accumulate in injured regions and draw fluid into the brain parenchyma (actually increasing ICP).
  • Effective dose = 0.25 – 1 Gram /kg.

 

So when you tell someone to call your friendly neurosurgeon about the child head trauma who has become bradycardic and hypertensive, politely order someone else to draw up the 3% Saline … and say “STAT”… for once that term would actually apply.

 

References

Bell MJ, Kochanek PM. Pediatric traumatic brain injury in 2012: the year with new guidelines and common data elements. Crit Care Clin. 2013 Apr;29(2):223-38. PMID: 23537673. [PubMed] [Read by QxMD]

Kochanek PM, Carney N, Adelson PD, Ashwal S, Bell MJ, Bratton S, Carson S, Chesnut RM, Ghajar J, Goldstein B, Grant GA, Kissoon N, Peterson K, Selden NR, Tasker RC, Tong KA, Vavilala MS, Wainwright MS, Warden CR; American Academy of Pediatrics-Section on Neurological Surgery; American Association of Neurological Surgeons/Congress of Neurological Surgeons; Child Neurology Society; European Society of Pediatric and Neonatal Intensive Care; Neurocritical Care Society; Pediatric Neurocritical Care Research Group; Society of Critical Care Medicine; Paediatric Intensive Care Society UK; Society for Neuroscience in Anesthesiology and Critical Care; World Federation of Pediatric Intensive and Critical Care Societies. Guidelines for the acute medical management of severe traumatic brain injury in infants, children, and adolescents–second edition. Pediatr Crit Care Med. 2012 Jan;13 Suppl 1:S1-82. PMID: 22217782. [PubMed] [Read by QxMD]

Author

Sean M. Fox
Sean M. Fox
Articles: 586

One comment

  1. […] can lead to some confusion when it comes to its management.  We recently discussed the use of mannitol and hypertonic saline for pediatric traumatic brain injury, but when should we consider these medications for the patient presenting with […]

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