Youmans Neurological Surgery

1. Critical care management of
traumatic brain injury
Youmans Chapter 334
Claudia Robertson
Leonardo Rangel-Castilla

2. Outline
• Traumatic brain injury
• Neurological intensive care monitoring
• Neurological intensive care management

3. Traumatic brain injury

4. Traumatic brain injury
• The primary injury : occurs before arrival at the hospital
• The secondary injury : prevent secondary ischemic insult
• Factor
– Age
– Preinjury health
– Genetic factors : ε4 allele of the apolipoprotein E gene 
worst outcome

5. Primary brain injury
• Concussion : loss of consciousness < 6 hr with amnesia
• DAI : traumatic coma than 6 hr
– Mild DAI : coma 6 – 24 hr
– Moderate DAI : longer than 24 hr with decerebrate posturing
– Severe DAI : : longer than 24 hr with decerebrate posturing or
flaccidity

6. Neurological intensive care monitoring
• Monitor neurological status
• Monitor for secondary injury processes
– Intracranial hypertension
– Cerebral ischemia
• Monitoring for secondary ischemic insult
– Cerebral cause
– Systemic cause

7. Monitoring of Neurological status
• Mental status
• Cranial nerve
• Pupillary
• Motor function
• 24 hr for one sheet

8. Monitor for secondary injury processes
• Intracranial hypertension
• Cerebral ischemia

9. Intracranial hypertension
• Ventriculostomy catheter is standard
– Tip at frontal horn of lateral ventricle
– Can be reset to zero
– Intermittent drainage CSF
• Microsensor transducer, fibreoptic transducer
– Subdural space or into brain tissue
– No lumen to become obstruct
– Cannot reset to zero
• Insert at end of the surgical procedure or after CT scan
• Continue as long as treatment of intracranial
hypertension required (3-10 days)

10. Intracranial hypertension

11. Intracranial hypertension
• Complication
– Ventriculitis
• Risk factor : IVH,SAH,cranial fracture with CSF
leakage,craniotomy, systemic infection
• Increasing risk for first 10 day
• Systemic prophylactic antibiotics and routine catheter
exchange are not recommended in the current TBI
guidelines
• Reducing infection : ATB-impreanated, minimize duration
– Hemorrhage
• 1-2%
• Coagulopathy(INR > 1.6)

12. Intracranial hypertension
• Normal intracranial pressure values
– Resting < 10 mmHg
– Sustain > 20 mmHg  abnormal, management in TBI
– Moderate Intracranial hypertension : 20-40 mmHg
– Severe : > 40 mmHg
• Indications for intracranial pressure monitoring
– severe TBI : defined as a GCS score of 3 to 8 after resuscitation
and abnormal findings on CT (level II recommendation)
– severe TBI and normal CT findings if two or more of the following
features are present at admission: age older than 40 years,
unilateral or bilateral motor posturing, or systolic BP lower than
90 mm Hg (level III recommendation)

13. Cerebral ischemia
• Monitor cerebral perfusion
– Cerebral perfusion pressure
• CPP = MAP – ICP
• Normal lower regulation : 50 mmHg
• Limit to ischemia from decrease BP or increase ICP
– Transcranial Doppler flow Velocity
• Flow volume = cross sectional area x Flow velocity
– Cerebral blood flow
• Classic Kety-Schmidt technique with nitrous oxide
• Stable xenon-CT or perfusion CT
• Thermal diffusion method
• Laser Doppler method

14. Cerebral ischemia
• Monitor cerebral perfusion
– Cerebral blood flow Adequacy
• Jugular venous Oxygenation Saturation(SjVO2)
• Brain tissue Po2
• Adequacy of CBF relative to cerebral metabolic requirement
• When CBF is low (25 to 30 mL/100 g per minute)
– appropriate cerebral metabolic requirements : SjVo2
normal
– brain is hypoperfused  oxygen extraction increase 
Sjvo2 decrease

15. Cerebral ischemia
• Monitor cerebral perfusion
– Cerebral blood flow Adequacy
• Jugular venous Oxygenation Saturation(SjVO2)
• Mortality was higher in pt with one episode(37%) or
multiple episode of desaturation(69 %) than in those no
episode(21%)
• Normal 55%-77%
• High SjVO2(> 75%) : hyperemia or after infarction
• Sjvo2 < 50 % TBI guidline recommend treat
• Complication : carotid artery rupture, injury to nerves in
the neck, pneumothorax, infection, increase ICP, venous
thrombosis

16. Cerebral ischemia
• Monitor cerebral perfusion
– Cerebral blood flow Adequacy
• Brain tissue Po2
– Sjvo2 can’t identified regional ischemia
– Normal 20-40 mmHg
– < 15 mmHg : TBI guidline recommend treat

17. Monitoring for secondary ischemic insult
• Monitor for cerebral causes of secondary ischemic insult
– Intracranial hypertension
• Most common cause of jugular venous desaturation
– Seizures
• CMRO2 increase 150%-250%
• CBF is marginal or uncoupled  cerebral ischemia
• Pt are often sedated, seizure may be subclinical  monitor
EEG

18. Monitoring for secondary ischemic insult
• Monitor for systemic causes of secondary insult
– Hypotension
• Ability to main normal CBF (wide range mean BP 50 – 150
mmHg)  TBI lose of autoregulation
• Increase mortality rate by 150%
• Arterial catheter : goal MAP greater than 80-90 mmHg 
CPP remain at least 60 mmHg
• Most common cause of Sjvo2 desaturation

19. Monitoring for secondary ischemic insult
• Monitor for systemic causes of secondary insult
– Hypoxia
• Decrease in arterial Po2  increase in CBF  vasodilatation
 increase ICP
• Pulmonary complicatiom  hypoxia
• Pulse oximetry : >95% arterial oxygen saturation

20. Monitoring for secondary ischemic insult
• Monitor for systemic causes of secondary insult
– Hypocapnia
• Hyperventilation  vasoconstrict  reduce global CBF and
cerebral volume
• Hyperventilation  rapidly lower ICP
• End-tidal Co2 in pt without pulmonary disease
• ABG in pulmonary pt
• Secondary cause of Sjvo2 desaturation

21. Monitoring for secondary ischemic insult
• Monitor for systemic causes of secondary insult
– Anemia
• Decrease CaO2  increase in CBF
• TBI, cerebral vasculature can’t dilate  drop in CaO2 
ischemia
• Hemoglobin should be measure at least daily
– Fever
• Increase metabolic rate 10-13 % per 1 C
• Tempearatue at lateral ventricle, epidural space, tympanic
membrane, rectum

23. Neurological intensive care
management
• General measure to minimize intracranial
hypertension/Improve cerebral perfusion
• Other general measures
• Timing of surgery for other injuries
• Treatment of secondary injury processes : intracranial
hypertension
• Treatment of secondary ischemic insult

24. General measure to minimize intracranial
hypertension/Improve cerebral perfusion
• Minimize venous outflow resistance
– head elevation 30 , head neutral position
• Sedation/Analgesia
– Avoid drug hypotensive side effect
– Propofal : short half-life, decrease BP > decrease ICP  reduce
CPP
– Propofal infusion syndrome : hyperkalemia, hepatomegaly,
lipemia, metabolic acidosis, myocardial failure, rhabdomyolysis,
and renal failure (5 mg/kg per hour)

25. General measure to minimize intracranial
hypertension/Improve cerebral perfusion
• Treatment of systemic hypertension
– SBP > 160 mmHg, autoregulation is impaired after TBI
– Increase ICP  cerebral edema
– Nicardipine : short acting,reverse and prevent vasospasm in pt with
moderate to sever TBI
• Airway protection/controlled ventilation
– Coma pt can’t protect airway  intubated
– Hypoxia,hypercapnia

26. General measure to minimize intracranial
hypertension/Improve cerebral perfusion
• Treatment of fever
– Potent cerebral vasodilator and increase ICP
– Increase cerebral metabolic requirement
• Prevention of seizure
– Risk factor : subdural hematoma, skull fracture, loss of
consciousness or amnesia > 1 day, > 65 years old
– Phenyltoin : reduce incidence during in the first week then
tapered and discontinue
– Levetiracetam :not require serum monitoring

27. Other general measures
• Prevention of ventilator-associated pneumonia 40%
– Association with aspiration
– Prophylaxis : cefuroxime 1500 mg IV for 2 dose or
Unasyn(ampicillin - sulbactam) 3 gm iv q 6 hr x 3 days
– Oral intubation, continue aspiration of subglottic secretion, ET
cuff at least 20 cmH2O, semirecumbent position
• Prophylaxis for thromboembolism 58%
– Risk factor : spinal cord injury, pelvic, femoral or tibial fracture ,
surgery , blood transfusion and old age
– Venous compression device preferred low dose heparin

28. Other general measures
• Prophylaxis for gastric ulcers
– Early erosion can progress to clinical significant hemorrhage
– Risk factor : severity of brain lesion, burn > 25 of BSA,
respiratory failure, hypotension, sepsis, jaundice, peritonitis,
coagulopathy, and hepatic failure
– H2blocker : increase risk for nosocomial pneumonia
– Proton pump inhibitor or sucralfate for prophylaxis
• Prophylaxis ATB to prevent meningitis
– Associate with otorrhea and rhinorrhea
– ATB recommend only when symptom or sign of meningitis
develop

29. Other general measures
• Nutritional support
– Sever head injury : hypermetabolic and catabolic stage
– TBI : 140% normal resting energy expenditure(REE)
– Enteral feeding as soon as possible
– Gradually increase feeding to full caloric in 1 wk

30. Management of Fluid/Electrolyte
• Hyponatremia syndrome
• Hypernatremia : Diabetes insipidus
• Hyperglycemia
• Hypopituitarism

31. Hyponatremia syndrome
• SIADH and cerebral salt wasting
• SIADH : secretion of ADH
– hyponatremia (serum sodium <135 mEq/L)
– hypo-osmolarity (serum osmolarity <280 mOsm/L)
– urine osmolarity greater than serum osmolarity
– inappropriately high urine sodium concentration (>40 mEq/L)
– Rx : limitation fluid intake 800-1000 ml/day
– Severe hyponatremia with symptoms  hypertonic NSS
• CSW : circulating natriuretic factor
– Hypovolemic,high urine serum sodium(>40 mEq/L)
– Rx : replacement with NSS
– Sodium loss in urine : salt tablet

32. Hyponatremia syndrome

33. Hypernatremia : Diabetes insipidus
• inadequate circulating quantities of ADH, which results in
an inability to concentrate urine
• hypovolemic hypernatremia
• disruption of the hypothalamic-hypophysial axis : severe
brain injury is usually a grave prognostic sig
• Mild to moderate DI : water replacement, may
exacerbate intracranial hypertension
• intravenous administration of aqueous desmopressin
acetate (DDAVP), 2 to 4 µg, will decrease free water
clearance for 8 to 12 hours
• Correct slowly over a period of 48 hours

34. Hypoglycemia
• 80-110 mg/dL
• Reduction in infection, acute renal failure

35. Hypopituitarism
• Pathologic : hemorrhage of hypothalamus, hemorrhage of posterior
lobe, infarction of the anterior pituitary
• Adrenal insufficiency : hypotension, hypoglecemia, hyponatremia
• Risk factor
• common in younger patients
• severely injured patients
• patients with preceding ischemic events (hypoxia, hypotension,
severe anemia)
• patients who received etomidate
• use of barbiturate coma
• Rx : indication hypotension, hyponatemia
• Hydrocortisone 50-100 mg q 8 hr or continuous infusion 0.18
mg/kg/hr

36. Timing of surgery for other injuries
• Systemic injury life-threatening : go to surgery
• Non-emergency : postpone until intracranial
hypertension resolve

37. Treatment of secondary injury processes :
intracranial hypertension
• Pharmacologic paralysis
– analgesia/sedation : morphine or lorazepam
– muscle relaxant : cisatracurium or vecuronium
• Hyperventilation : Paco2 of 20 to 25 mm Hg
– not recommended in the current TBI guidelines
– Hyperventilation should be withdrawn over a period of several
days to avoid this increase in ICP
• Drainage of cerebrospinal fluid
– removal of 1 mL of CSF : not changeICP < 1 - 2 mm Hg
– brain becomes more swollen, the ventricles collapse

38. Treatment of secondary injury
processes : intracranial hypertension
• Osmotherapy
– Mannitol, peak effect 20-60 min, duiration 1.5 – 6 hrs
– 0.25 to 1 g/kg BW
– side effects : hypovolemia, hyperosmolarity(keep less than 320
mOsm), and renal failure
• Barbiturate coma
– loading dose is 10 mg/kg given over a 30-minute period,
followed by 5 mg/kg each hour for three doses, maintenance
dose is 1 to 2 mg/kg per hour

39. Treatment of secondary injury
processes : intracranial hypertension
• Hypothermia
– Reduce : cerebral metabolic rate, increased ICP, cerebral
edema formation, frequency of epileptic discharges, and opening
of the BBB
– 32°C and 33°C , rewarming period lasting less than 24 hours,
continue at least 24 hr
– Complication : thrombocytopenia, cardiovascular and pulmonary
complications, infections
• Decompresive craniectomy

40. Treatment of secondary ischemic insult
• cerebral ischemia
– goal of therapy is to optimize oxygen delivery to the brain
– Hb : 10 g/dl
• Treatment of Hypotension
– CVP monitor
– Cystalloid solution for hypovolemia
– Other condition : cardiac contusion or tamponade, and tension
pneumothorax
• Treatment of Hypoxia
– PEEP ; increase ICP by increasing intrathoracic pressure,
central venous pressure, and cerebral venous pressure,
decreasing venous return to the heart, BP can be reduced. 
reduction in CPP

41. Treatment of Secondary Ischemic
Insults
• Treatment of Anemia
– hematocrit of greater than 25% to 30% may be required for
maximal oxygen delivery to the brain.
• Treatment of Seizures
– Diazepam, 5 to 10 mg intravenously, or lorazepam, 2 to 3 mg
intravenously
– Phenyltoin loading dose of 15 to 20 mg/kg
Maintenance doses of phenytoin, 300 to 400 mg/day
• Treatment of Cerebral Vasospasm
– treated similar to vasospasm after SAH
– Nimodipine
– Hypervolemic hemodilution, hypertension