Traumatic Brain Injury

ED Critical Care Conference: Sept 2013

The Curious Case of AMS with an (initially) Normal CT Head

presented by Dr. Andy Grock

Case: 24 yo M, no pmhx presents AMS s/p assault. MRI shows Diffuse Axonal Injury.

TBI Discussion

Severity by GCS Mild >13 Moderate >9 and <12 Severe <8

TBI actually two injuries – the initial trauma followed by secondary harm from the following: ischemia (vasospasm/vascular injury), electrolyte imbalance, neurotransmitter excite-toxicity, ionic shifts, depolarization of brain cells, and mitochondria dysfunction.
These secondary injuries may be prevented or lessened by us in the ED.

Goals of Care in ED

Prevent Hypoxia – keep paO2 >60, Sat >90% (level 3 recommendation). If GCS < 8 or if deteriorating GCS, pt should be intubated to prevent hypoxia.

Prevent Hypotension – SBP <90, one value <90 associated with increased morbidity and double mortality. (level 2 recommendation). Give fluids even if ICP elevated if the patient is hypotensive.

Hyperventilation – Goal PCO2 30-35, can delay herniation in the short term (level 3 recommendation), prolonged hyperventilation leads to profound vasoconstriction and ischemia and is NOT recommended (level 2 recommendation)

Hyper-osmotic agents – Mannitol, 0.25 g/kg, works in minutes, peaks at 1 hr (level 2 rec.)

Hypothermia – No decrease in mortality (level 3 recommendation)

When is ICP Monitoring Indicated?

GCS <8, Any suspected increased ICP, CT scan showing mass effect such as hematoma, contusion, swelling, hydrocephalus. ( Level 2 recommendation)
Normal CT with 2 out of the following 3

Age >40, unilateral or bilateral motor posturing, a systolic BP<90 (level 3 rec.)

Why Measure ICP

Studies have shown decreased mortality with its use.

What types of ICP Monitoring Exist?

External Ventricular Drain

Catheter placed through brain parenchyma with tip in ventricle

Gold standard of measurement AND therapeutic as you can remove fluid to relieve pressure.

Subarachnoid Bold

Through skull/subdural. Does not penetrate brain

Less accurate measurements

Our Patient Also Had…

Symptoms of autonomic instability (high blood pressure, tachycardia, fever, posturing, pupillary dilation). What is this from?

Initially described as Autonomic dysfunction syndrome (ADS), is when TBI leads to altered autonomic activity. Now called PAID —paroxysmal autonomic instability with dystonia, it is characterized by temperature > 38.5º C, hypertension, a pulse rate of at least 130 beats per minute, a respiratory rate of at least 140 breaths per minute, intermittent agitation, and diaphoresis; these are accompanied by dystonia (rigidity or decerebrate posturing for a duration of at least 1 cycle per d for at least 3 d).

Some possible beneficial treatments include chlorpromazine, bromocriptine, propanolol, clonidine, and morphine.

Resources:

Traumatic brain injury: Epidemiology, classification, and pathophysiology uptodate.com. newproxy.downstate.edu/contents/traumatic-brain-injury-epidemiology-classification-and-? Detected Language=en&source=search_result&search=traumatic+brain+injury&selectedTitle=1% 7E133&provider=noProvider

Management of acute severe traumatic brain injury: http://www.uptodate.com.newproxy. downstate.edu/contents/management-of-acute-severe-traumatic-brain-injury?source=see_link

ACEP: Traumatic Brain Injury, Neuroimaging and Decisionmaking in Adult Mild Traumatic Brain Injury in the Acute Setting (December 2008), Complete Clinical Policy on Mild Traumatic Brain Injury

Intracranial pressure monitoring and outcomes after traumatic brain injury: Lane PL, Skoretz TG, Doig G, Girotti MJSOCan J Surg. 2000;43(6):442.

Guidelines for the management of severe traumatic brain injury. VI. Indications for intracranial pressure monitoring. AUBrain Trauma Foundation, American Association of Neurological Surgeons, Congress of Neurological Surgeons, Joint Section on Neurotrauma and Critical Care, AANS/CNS, Bratton SL, Chestnut RM, Ghajar J, McConnell Hammond FF, Harris OA, Hartl R, Manley GT, Nemecek A, Newell DW,Rosenthal

Neurotrauma. G, Schouten J, Shutter L, Timmons SD, Ullman JS, Videtta W, Wilberger JE, Wright DWSOJ 2007;24 Suppl 1:S37.

Monitoring intracranial pressure in traumatic brain injury. Smith M; Anesth Analg. 2008 Jan;106 (1):240-8. doi: 10.1213/01.ane.0000297296.52006.8e

Rosen’s Emergency Medicine &th Edition, Chapter 13 Head Injury

Pharmacological management of Dysautonomia following traumatic brain injury. Brain Inj. 2004; 18(5):409-17 (ISSN: 0269-9052) Baguley IJ; Cameron ID; Green AM; Slewa-Younan S; Marosszeky JE; Gurka JA Brain Injury Rehabilitation Service, Westmead Hospital, Wentworthville, NSW, Australia.