Traumatic Brain Injury Flashcards
What is the definition of Traumatic Brain Injury
A disruption in the normal function of the brain that can be caused by a bump. blow, or jolt to the head or a penetrating head injury
T/F: A concussion is a type of TBI
True
What are the three features for the Glasgow Coma Score/ what is the lowest and highest score
Eye opening, verbal response, best motor response/ 3 and 15 (CANNOT RECEIVE A ZERO)
What is considered a mild GSC score, moderate, severe
13-15: normal to lethargic with mild disorientation
9-12: Lethargic to obtunded, follows commands if aroused, confused
Less than or equal to 8: Doesn’t follow commands/ localizes pain and posturing
What are the two types of injury pertaining to TBI
Primary injury: Direct insult to the brain
Secondary: delayed- metabolic and biochemical changes
How is Cerebral perfusion pressure calculated (CPP), goal CPP, goal Intracranial pressure
MAP - ICP, 60-70 mmHg, less than 22 mmHg
What is the autoregulation to maintain constant cerebral blood flow (CBF), what occurs if there is low CBF AND a loss of autoregulation, what occurs if there’s high CBF and low autoregulation
Cerebral blood vessels can dilate or constrict to maintain constant CBF, cerebral ischemia, Increased ICP
What states would be treated pharmacologically for acute management of Severe TBI
Systemic hypotension, intracranial hypertension, coagulopathy management
What is the long term goal of therapy
REcovery or salvage of neurological function
What are the short term goals
Control intracranial hypertension: ICP less than 22 mmHg
Optimizing CPP: Goal of 60-70 mmHg
What is the goal blood pressure in a TBI patient, MAP
SBP greater than 100 mmHG (Age 50-69) or 110 mmHg (Age 15-49 OR greater than 70), 80-100
What fluid can be given for systemic hypotension, what if there is no response to the fluids, acute blood loss (greater than 30%)
Isotonic saline (0.9% NaCl): 1-2 liters, vasopressors: Norepinephrine, Packed red blood cells
In order to treat Intracranial hypertension (ICP greater than 22) what therapy is the best to use and what are the options of the therapy
Hyperosmolar therapy: Mannitol and Hypertonic saline
What is the MOA of hyperosmolar agents, additional effects
Mobilization of water from brain to vasculature through an osmotic gradient, reduces blood viscosity and decreases cerebral blood volume
How early can manitol be given and how fast does it work, what is the dose
Soon as the patient presents, within minutes, BOLUS of 0.25-1 g/Kg (continous infusion not recommended)
What are the adverse effects of mannitol
Diuresis leading volume contraction and hypotension, AKI due to increase in serum osmolality (mOSM greater than 320 gets NO MANNITOL), rebound increase in ICP since BBB is opened and there is mannitol accumulation
What are 5 common hypertonic saline solutions indicated for prolonged intracranial hypertension, which is the ONLY one to be given PERIPHERAL
1.5%, 2%, 3%, 7.5%, 23.4%/ 1.5%
What is the onset of hypertonic saline and duration REGARDLESS of concenctration
Rapid, 2-6 hours
What are the adverse effects of hypertonic saline
Worsening hypernatremia (Threshold is Sodium greater than 160mEq/L), Central pontine myelinolysis/CPM (Serum Sodium should not raise greater than 0.5 mEq/L/hr, Worsening pulmonary edema
What is another route of therapy for elevated ICP, how
Sedation and Analgesia: reduction in cerebral metabolic rate of oxygen (CMRO2) leading to a decrease in cerebral blood flow, cerebral blood volume, and intracranial volume
What medications are inidicated for use in sedation of patients with TBI
Propofol (rapid onset and short duration), Midazolam or other BZDs (does not lower ICP), fentanyl or other opioids
What is the last resort for reducting ICP if hyperosmolar therapy and sedation does not work, MOA
Barbituates: Pentobarbital, Reduction cerebral metabolic rate of oxygen causes a decrease in cerebral blood and cerebral blood volume lower ICP
What is the loading dose, maintenance dose
10 mg/kg over 30 minutes THEN 5 mg/kg/hr for 3 hours/ 1 mg/kg/hr
What is the goal serum concetration, adverse effects
30-40 mg/dL, hypotension (Keep CPP between 60 to 70)
What should be done if ICP is stable by pentobarbital for 24 - 48 hours
Taper over 24 to 72 hours
What norpharmacologic ways to lower the ICP
increase the head of the bed by 30 degrees (avoid hypotension), prophylatic hyperventilation after 24 hours(MUST BE SHORT TERM)
T/F: Decompressive craniectomy is the number one way to reduce ICP
False: Bifrontal DC is not recommended to reduce ICP
T/F: If a patient is taking anticoagulation medications they must be reversed if TBI is present
True
What are seizure prophylatics for patients with TBI
Phenytoin or fosphenytoin within 7 days of injury, valproic acid (increased mortality), levetiracetam
What is the loading dose for phentyoin given for seizure prophylaxis, usual maintenance dose, duration, therapeutic range
12-20 mg/kg (max infusion of 50mg/minute), 5-7 mg/kg/day, 7 days, Total: 10-12 mcg/ml with free at 1-2 mcg/ml
What is the dosing for levetiracetam for seizure prophylaxis in patients with TBI
1000 mg IV every 12 hours
What are the options for VTE prophylaxis
LMWH or low dose unfractionated heparin
T/F: Feeding patients to attain basal caloric replacement by at least the 5th day and at most the 7th day post injury is recommended to decrease mortality
True
How does methylphenidate used in TBI patients, beta-blockers
Improve memory and information processing, improve agitation and aggression
