Brain Brain and and

Spinal Cord Trauma Spinal Cord Trauma Mani K.C Vindhya M.DMani K.C Vindhya M.D

Asst Prof of AnesthesiologyAsst Prof of Anesthesiology

Nova Southeastern UniversityNova Southeastern University

ABC’s of Anesthesia for Traumatic Brain Injury (TBI) ABC’s of Anesthesia for Traumatic Brain Injury (TBI)

Airway management Airway management Blood pressure management Blood pressure management CO2 (Hyperventilate or not?) CO2 (Hyperventilate or not?) Diuretics or Dexamethasone? Diuretics or Dexamethasone? Early decompressive craniectomy Early decompressive craniectomy Fluid management Fluid management Glucose management Glucose management Hypothermia (Is it “cool” or not?) Hypothermia (Is it “cool” or not?) IV and Inhaled AnestheticsIV and Inhaled Anesthetics

Airway Management in TBI Airway Management in TBI

Head Intracranial pressure (ICP), altered mental status, uncooperative/combative patient

Neck Assume unstable C-spine

Airway Blood, injury, skull base fracture

Breathing Hypoxemia

Circulation Assume hypovolemia

Digestive Juices Assume full stomach

Issues in Intubating the Head-Injured Patient (JC Drummond, ASA Refresher Course Lecture 144: 1-7, 2000)

Principles for Resuscitating the Head-Injured PatientPrinciples for Resuscitating the Head-Injured Patient First ABC, then ICP.First ABC, then ICP. 1. The ABC’s initially take priority over ICP 1. The ABC’s initially take priority over ICP (JC Drummond, ASA Refresher Course Lecture 144: 1-7, 2000).(JC Drummond, ASA Refresher Course Lecture 144: 1-7, 2000). Secure the airway. Secure the airway. Breathing: Guarantee gas exchange, oxygenation and ventilation.Breathing: Guarantee gas exchange, oxygenation and ventilation. Stabilize the circulationStabilize the circulationThink associated injuries.Think associated injuries. 2. Unstable C-spine injury could lead to a cervical cord injury 2. Unstable C-spine injury could lead to a cervical cord injury (Doolan LA,O’Brien JF. Anaesth Int Care 13: 319-24, 1985).(Doolan LA,O’Brien JF. Anaesth Int Care 13: 319-24, 1985). If a rapid sequence induction and intubation, then... If a rapid sequence induction and intubation, then... Cricoid pressure (Sellick maneuver) & Manual in-line stabilization Cricoid pressure (Sellick maneuver) & Manual in-line stabilization

Which patients need immediate intubation? Which patients need immediate intubation?

Empirically, patients with a Glasgow Coma Empirically, patients with a Glasgow Coma Scale (GCS) Scale (GCS) << 8 require 8 require intubation and controlled intubation and controlled ventilation for airway and/or ICP control.ventilation for airway and/or ICP control.

Patients with a GCS of 9-12 require close observation. Patients with a GCS of 9-12 require close observation. Some of these will “talk and die” Some of these will “talk and die”

Delayed deterioration observed up to 48 hours after Delayed deterioration observed up to 48 hours after initial injury initial injury (Marshall LF (Marshall LF et al.et al. J Neurosurg 59: 285-8, 1983). J Neurosurg 59: 285-8, 1983).

Glasgow Coma Scale (GCS)Glasgow Coma Scale (GCS)

Eyes open Never 1 To pain 2 To speech 3 Spontaneously 4

Best verbal responses None 1 Garbled, incomprehensible sounds 2 Inappropriate words 3 Confused but converses 4 Oriented 5

Best motor responses None 1 Extension (decerebrate rigidity) 2 Abnormal flexion (decorticate rigidity) 3 Withdrawal 4 Localizes pain 5 Obeys commands 6

Total 3-15

C. Cervical Fractures are Common in Along with Traumatic Brain Injury

1. Cervical spine injury occurs in 2% of victims of blunt trauma (Crosby ET.Anesthesiology 104: 1293-1318, 2006.)

2. Higher incidence of cervical injury in patients who have experienced severe traumatic brain injury, as determined by:

A. low Glasgow Coma Scale (GCS) and B. Unconsciousness

Association between GCS and cervical spine injury (Demetriades D et al. J Trauma 48: 724-7, 2000).

Injury Severity (GCS Score) % of Patients with C-Spine Injury

13-15 1.4 % 9-12 6.8 % < 8 10 .2 %

4. Of those patients who need emergent intubation (GCS 4. Of those patients who need emergent intubation (GCS << 8), 8), roughly10% (1 in 10) have an associated C-spine injury!roughly10% (1 in 10) have an associated C-spine injury!

5. C-spine injuries may be missed by neck films or CT scans 5. C-spine injuries may be missed by neck films or CT scans (Crosby ET, Lui A. Can J Anaesth 37: 707-9, 1990; Drummond JC, ASA Refresher Course Lecture144: (Crosby ET, Lui A. Can J Anaesth 37: 707-9, 1990; Drummond JC, ASA Refresher Course Lecture144: 1-7, 2000).1-7, 2000).

Lateral X-ray misses 20% of C-spine fractures. Lateral X-ray misses 20% of C-spine fractures. Lateral and AP and odontoid views miss only 7%. Lateral and AP and odontoid views miss only 7%. 7 to 14% of C-spine fractures involve C7 and/or T1.7 to 14% of C-spine fractures involve C7 and/or T1.

Intubating the Head-Injured Patient Intubating the Head-Injured Patient 1. If pentothal (or etomidate)-sux-tube... 1. If pentothal (or etomidate)-sux-tube... (Drummond JC, ASA Refresher Course Lecture 144: 1-(Drummond JC, ASA Refresher Course Lecture 144: 1-

7, 2000)7, 2000)

a. Manual in-line stabilization (no pillow, head held rigid on backboard)a. Manual in-line stabilization (no pillow, head held rigid on backboard) Axial traction could lead to extension injury Axial traction could lead to extension injury Cricoid pressure Cricoid pressure Back of collar in place Back of collar in place Optimum exposure of vocal cords may be limited with in-line stabilizationOptimum exposure of vocal cords may be limited with in-line stabilization Not sniffing position Not sniffing position Case report: “Neurologic Deterioration with Airway Management in a C-spine-Case report: “Neurologic Deterioration with Airway Management in a C-spine-

injured Patient” injured Patient” (Hastings RH, Kelley SD. Anesthesiology 78: 580-3, 1993).(Hastings RH, Kelley SD. Anesthesiology 78: 580-3, 1993).

MVA; neck pain; 3 views “normal” MVA; neck pain; 3 views “normal” Delayed respiratory distress Succinylcholine, intubation Paraplegic Delayed respiratory distress Succinylcholine, intubation Paraplegic CT: C6-C7 prevertebral hematoma CT: C6-C7 prevertebral hematoma

Remember other intubation options Remember other intubation options (JC Drummond, ASA Refresher Course (JC Drummond, ASA Refresher Course Lecture 144: 1-7, 2000):Lecture 144: 1-7, 2000):

Fiberoptic oral / nasal Fiberoptic oral / nasal Blind nasal (not if basilar skull fracture) Blind nasal (not if basilar skull fracture) Light wand / stylettes Light wand / stylettes Augustine guide Augustine guide Glidescope, Bullard scope, etc. Glidescope, Bullard scope, etc. Retrograde cannulation Retrograde cannulation LMA (as backup for failed intubation) LMA (as backup for failed intubation) Cricothyrotomy Cricothyrotomy

Case reports: “Beware of the basilar skull fracture!” Case reports: “Beware of the basilar skull fracture!” a. “Complication from a naso-pharyngeal airway in a patient a. “Complication from a naso-pharyngeal airway in a patient

with a with a basilar skull fracture.” basilar skull fracture.” (Muzzi DA (Muzzi DA et al.et al. Anesthesiology 74: 366-8,1991) Anesthesiology 74: 366-8,1991)

b. “Intracranial placement of a nasotracheal tube after facial b. “Intracranial placement of a nasotracheal tube after facial fracture: a rare complication” fracture: a rare complication” (Marlow TJ, Goltra DD Jr, Schabel SI. J Emerg Med 15: (Marlow TJ, Goltra DD Jr, Schabel SI. J Emerg Med 15: 187-91, 1997)187-91, 1997)

Blood Pressure (BP) Management in TBI Blood Pressure (BP) Management in TBI Three historical strategies to manage MAP after TBI. Three historical strategies to manage MAP after TBI.

The strategy dependsThe strategy depends on the relationship of cerebral blood on the relationship of cerebral blood flow (CBF) to MAP after head injury flow (CBF) to MAP after head injury (Drummond JC, Patel PM. (Drummond JC, Patel PM. “Neurosurgical Anesthesia,” Chap. 53 in Miller RD ed., Miller’s Anesthesia, 6th ed., Churchill “Neurosurgical Anesthesia,” Chap. 53 in Miller RD ed., Miller’s Anesthesia, 6th ed., Churchill Livingstone, Philadelphia, 2005: pp. 2127-73.) Livingstone, Philadelphia, 2005: pp. 2127-73.)

Approach Assumption About Assumption About MAP Autoregulation

“Lund” Approach Abolished (steep rise) Avoid hyperemia, keep MAP down

“Edinburgh” Approach Abolished (gradual rise) Avoid decreased CBF, keep MAP up

“Birmingham” Approach Intact (but plateau lower) Avoid decreased CBF, keep MAP up

A new and evolving theme in neurosurgical management A new and evolving theme in neurosurgical management of TBI of TBI (JC(JC Drummond, ASA Refresher Course Lecture 144: 1-7, 2000)Drummond, ASA Refresher Course Lecture 144: 1-7, 2000)

1. We used to worry about cerebral 1. We used to worry about cerebral hyperemiahyperemia (too much (too much CBF), and tended to decrease BP.CBF), and tended to decrease BP.

2. Now we worry about cerebral ischemia (not enough CBF), 2. Now we worry about cerebral ischemia (not enough CBF), and tend to increase BP.and tend to increase BP.

Hypoperfusion is very common after TBI (on the first day) Hypoperfusion is very common after TBI (on the first day) Autoregulation is impaired. Autoregulation is impaired.

Brain is very vulnerable to secondary injury. Brain is very vulnerable to secondary injury.

Hypotension after TBI is associated with particularly “bad” outcomes. Impact of Hypoxia and/or Hypotension on Outcome after Closed Head Injury (GCS < 8) [at time of hospital arrival] (Chesnut RM et al. J Trauma 34: 216-22, 1993)

Number % Good or Moderate % Poor or Dead

Total 699 43% 57%

Normotension/normoxia 456 51% 49%

Hypotension (SBP<90) 113 24% 76%

Hypoxia (paO2 < 60) 78 45% 55%

Hypoxia and hypotension 52 6% 94%

““Deleterious effects of intraoperative hypotension on Deleterious effects of intraoperative hypotension on outcome in patients with severe head injuries” outcome in patients with severe head injuries” (Pietropaoli JA (Pietropaoli JA et alet al, J , J Trauma 33: 403-7, 1992)Trauma 33: 403-7, 1992)

53 blunt head injuries 53 blunt head injuries All required surgery. All required surgery.

ProblemsProblems surgeons reading anesthesia records surgeons reading anesthesia records retrospective methodology retrospective methodology

If SBP > 90 mm Hg intraoperatively, mortality = 25% If SBP > 90 mm Hg intraoperatively, mortality = 25% If SBP < 90 mm Hg intraoperatively, mortality = 82% (P < 0.001)If SBP < 90 mm Hg intraoperatively, mortality = 82% (P < 0.001)

Brain Trauma Foundation: Recommendations to Manage Severe TBI Brain Trauma Foundation: Recommendations to Manage Severe TBI (Joint(Joint Section on Neurotrauma and Critical Care, The Brain Trauma Section on Neurotrauma and Critical Care, The Brain Trauma Foundation, Surgeons Foundation, Surgeons

AAoN: Guidelines for the Management of Severe Head Injury. Park AAoN: Guidelines for the Management of Severe Head Injury. Park Ridge, IL, The American Association of Neurological Surgeons, 1995.) Ridge, IL, The American Association of Neurological Surgeons, 1995.)

Standards, Guidelines, and Options Standards, Guidelines, and Options Standards Standards – represent principles that reflect a– represent principles that reflect a highhigh degree of clinicaldegree of clinical

certaintycertainty Guidelines Guidelines – reflect a– reflect a moderatemoderate degree of clinical certaintydegree of clinical certainty Options Options – represent principles for which there is– represent principles for which there is unclearunclear clinicalclinical

certaintycertainty Resuscitation of BP and Oxygenation Resuscitation of BP and Oxygenation Standard Standard – none– none Guideline Guideline – Hypotension (SBP < 90 mm Hg) or hypoxia (apnea or– Hypotension (SBP < 90 mm Hg) or hypoxia (apnea or

cyanosis in the field or a paO2 < 60 mm Hg) must be scrupulously cyanosis in the field or a paO2 < 60 mm Hg) must be scrupulously avoided, if possible, orcorrected immediatelyavoided, if possible, orcorrected immediately

Option Option – MAP should be maintained above 90 mm Hg throughoutthe – MAP should be maintained above 90 mm Hg throughoutthe patient’s coursepatient’s course

BP Management in TBI: What’s the Bottom Line BP Management in TBI: What’s the Bottom Line for Us?for Us?

1. Avoid hypotension (SBP < 90 mm Hg) if possible, 1. Avoid hypotension (SBP < 90 mm Hg) if possible, or correct itimmediatelyor correct itimmediately

2. MAP > 70-80 mm Hg is reasonable2. MAP > 70-80 mm Hg is reasonable

CO2 Management in TBICO2 Management in TBI Should we hyperventilate? Should we hyperventilate?

Concepts in TBI have totally changed Concepts in TBI have totally changed Hyperventilation and hypocapnia (paCO2 of 25): Hyperventilation and hypocapnia (paCO2 of 25):

Decreases ICP Decreases ICP But also decreases CBF, predisposing to cerebral ischemia But also decreases CBF, predisposing to cerebral ischemia Some studies showing that hyperventilation may be deleterious Some studies showing that hyperventilation may be deleterious

in TBI: in TBI: ““Does acute hyperventilation provoke cerebral oligaemia in Does acute hyperventilation provoke cerebral oligaemia in

comatose comatose patients after acute head injury?” patients after acute head injury?” (Cold GE. Acta Neurochir 96: 100-6, 1989)(Cold GE. Acta Neurochir 96: 100-6, 1989)

27 comatose head injury patients Intra-carotid 133Xe to measure 27 comatose head injury patients Intra-carotid 133Xe to measure CBF paCO2: From 35 to 25 CBF paCO2: From 35 to 25

CBF < 20: Foci went from 9/27 to 15/27 CBF < 15: Foci went CBF < 20: Foci went from 9/27 to 15/27 CBF < 15: Foci went from 2/27 to 9/27 from 2/27 to 9/27

““Effect of hyperventilation on regional cerebral blood flow Effect of hyperventilation on regional cerebral blood flow in head- injured children” in head- injured children” (Shippen P (Shippen P et al.et al. Crit Care Med 25: 1402-9, 1997) Crit Care Med 25: 1402-9, 1997)

23 children; isolated TBI; GCS from 3 to 7 paCO2 > 35, 25-23 children; isolated TBI; GCS from 3 to 7 paCO2 > 35, 25-35, and < 25 mm Hg Baseline CBF (Xe CT) slightly 35, and < 25 mm Hg Baseline CBF (Xe CT) slightly decreased CMRO2 1/3rd of normal decreased CMRO2 1/3rd of normal

% ischemic: Normocapnia (28.9%) vs. hypocapnia (73.1%) % ischemic: Normocapnia (28.9%) vs. hypocapnia (73.1%) Moderate hyperventilation induced a harmful reduction in Moderate hyperventilation induced a harmful reduction in

brain tissue PO2 brain tissue PO2 (Imberti R et al. J Neurosurg 96: 97-102, 2002).(Imberti R et al. J Neurosurg 96: 97-102, 2002).

Brain Trauma Foundation: Recommendations Regarding Brain Trauma Foundation: Recommendations Regarding HyperventilationHyperventilation

StandardStandard: (One of the few) In the absence of increased ICP, chronic: (One of the few) In the absence of increased ICP, chronic prolonged hyperventilation therapy (paCO2 < 25 mm Hg) should be prolonged hyperventilation therapy (paCO2 < 25 mm Hg) should be avoided after severeTBIavoided after severeTBI

GuidelineGuideline: The use of prophylactic hyperventilation therapy (paCO2: The use of prophylactic hyperventilation therapy (paCO2 < 35< 35 Hg) during the 1st 24 hours after severe TBI should be avoided because it Hg) during the 1st 24 hours after severe TBI should be avoided because it can compromise cerebral perfusion during a time when CBF is decreased. can compromise cerebral perfusion during a time when CBF is decreased.

OptionOption: Hyperventilation therapy may be necessary for brief periods when: Hyperventilation therapy may be necessary for brief periods when there is acute neurologic deterioration, or for longer periods of time if there there is acute neurologic deterioration, or for longer periods of time if there is intracranial HTN refractory to sedation, paralysis, CSF drainage, and is intracranial HTN refractory to sedation, paralysis, CSF drainage, and osmotic diuretics.osmotic diuretics.

Hyperventilation in TBI: What’s the Bottom Line for Us? Hyperventilation in TBI: What’s the Bottom Line for Us? Don’t routinely hyperventilate the TBI patient intra-operatively. Don’t routinely hyperventilate the TBI patient intra-operatively. A paCO2 of 35 mm Hg is reasonable. A paCO2 of 35 mm Hg is reasonable. Hyperventilate to paCO2 of 25 only if neededHyperventilate to paCO2 of 25 only if needed (i.e., “swollen brain”). (i.e., “swollen brain”).

Diuretics or Dexamethasone in TBI? Diuretics or Dexamethasone in TBI? Diuretics in TBI? Diuretics in TBI?

The osmotic diuretic The osmotic diuretic mannitolmannitol is often employed in the setting is often employed in the setting of TBI. of TBI.

Mannitol requires an intact blood:brain barrier to work Mannitol requires an intact blood:brain barrier to work The blood:brain barrier is probably not intact in areas of severe The blood:brain barrier is probably not intact in areas of severe

TBI. TBI. But we use mannitol anyway, hoping it will “shrink” normal But we use mannitol anyway, hoping it will “shrink” normal

brain. brain. Dexamethsone in RBI? Dexamethsone in RBI? Corticosteroids are thought to be Corticosteroids are thought to be

beneficial tobeneficial to shrink edema around solid brain tumors. They are not shrink edema around solid brain tumors. They are not beneficial, and may even be harmful, in TBI beneficial, and may even be harmful, in TBI (Dearden NM et al. J Neurosurg 64: (Dearden NM et al. J Neurosurg 64:

81-8, 1986; Alderson P, Roberts I. BMJ 314: 1855-9, 1997; Yates RI et al, Lancet 364 (9442): 1321-8, 2004).81-8, 1986; Alderson P, Roberts I. BMJ 314: 1855-9, 1997; Yates RI et al, Lancet 364 (9442): 1321-8, 2004). Bottom Line? Bottom Line? Don’t use steroids in TBI! (But do use high-dose Don’t use steroids in TBI! (But do use high-dose

SolumedrolSolumedrol [methylprednisolone] for acute spinal cord injury!) [methylprednisolone] for acute spinal cord injury!)

Early Decompressive CraniectomyEarly Decompressive Craniectomy Early decompressive craniectomy for intractable Early decompressive craniectomy for intractable

intracranial hypertension is “what’s new” in TBI. intracranial hypertension is “what’s new” in TBI. 2006 Study: “better-than-expected functional 2006 Study: “better-than-expected functional

outcome in patients with medically uncontrollable outcome in patients with medically uncontrollable ICP and/or brain herniation, compared with outcomes ICP and/or brain herniation, compared with outcomes in other control cohorts...” in other control cohorts...” (Aarabi B et al. J Neurosurg 104: 469:79, 2006). (Aarabi B et al. J Neurosurg 104: 469:79, 2006).

““...insufficient data to support the routine use of DC ...insufficient data to support the routine use of DC [decompressive craniectomy] in TBI” [decompressive craniectomy] in TBI” (Schirmer CM et al. (Schirmer CM et al. Neurocritical Care 8: 456-70, 2008). Neurocritical Care 8: 456-70, 2008).

Bottom line for us? More “midnight specials” while Bottom line for us? More “midnight specials” while on call? on call?

Fluid Management in TBIFluid Management in TBI Basic principles of fluid management in TBI Basic principles of fluid management in TBI

The mantra in intracranial neuro used to be “Run ‘em dry.” The mantra in intracranial neuro used to be “Run ‘em dry.” Now the mantra is “Run ‘em even.” Now the mantra is “Run ‘em even.” Avoid hypovolemia with fluid replacement. Avoid hypovolemia with fluid replacement. For normal craniotomy, For normal craniotomy,

Deficit + Deficit + Hourly maintenance + Hourly maintenance + Cover urine cc for cc Cover urine cc for cc Cover blood loss 3:1 with crystalloid Cover blood loss 3:1 with crystalloid

A negative fluid balance is associated with a bad outcome. In humans, A negative fluid balance is associated with a bad outcome. In humans, exceeding certain thresholds was associated with an increased percentage of exceeding certain thresholds was associated with an increased percentage of

patients with poor outcome patients with poor outcome (Clifton GL et al. Fluid thresholds and outcome from severe brain injury. CritCare (Clifton GL et al. Fluid thresholds and outcome from severe brain injury. CritCare Med 30: 739-45, 2002):Med 30: 739-45, 2002):

Fluid balance < -594 mlFluid balance < -594 ml Mean arterial pressure < 70 mm Hg Intracranial pressure > 25 mm Hg Mean arterial pressure < 70 mm Hg Intracranial pressure > 25 mm Hg

Which fluid is best in TBI? Which fluid is best in TBI? Usually normal saline is recommended as the crystalloid Usually normal saline is recommended as the crystalloid

for resuscitation. for resuscitation. NSS is slightly hypertonic. NSS is slightly hypertonic. Lactated Ringer’s Lactated Ringer’s

Is slightly hypotonic + Is slightly hypotonic + Lactate converted to glucose in liver Lactate converted to glucose in liver

Give blood or colloid as needed. Give blood or colloid as needed. In an experimental model of TBI, brain water content In an experimental model of TBI, brain water content

was increased with was increased with both ½ NSS and NSS, relative to blood or both ½ NSS and NSS, relative to blood or colloid colloid (Drummond JC et al. Anesthesiology 88:993-1002, 1998).(Drummond JC et al. Anesthesiology 88:993-1002, 1998).

Glucose Management in TBIGlucose Management in TBI Hyperglycemia is detrimental. Hyperglycemia is detrimental.

Elevated glucose levels are deleterious in cerebral ischemia. Elevated glucose levels are deleterious in cerebral ischemia. In animal models, hyperglycemia at onset of ischemia worsens In animal models, hyperglycemia at onset of ischemia worsens

outcome outcome In humans, hyperglycemia is associated with a worsening of post-In humans, hyperglycemia is associated with a worsening of post-

ischemic brain injury ischemic brain injury Why? Intracellular acidosis probably injures neurons and glia Why? Intracellular acidosis probably injures neurons and glia (Wass (Wass

CT, Lanier WL. Mayo Clin Proc 71: 801-12, 1996)CT, Lanier WL. Mayo Clin Proc 71: 801-12, 1996)

Glucose Management in TBI: What’s the Bottom Line? Glucose Management in TBI: What’s the Bottom Line? Monitor glucose levels to maintain “normoglycemia” as rigidly as Monitor glucose levels to maintain “normoglycemia” as rigidly as

possible. possible. Avoid IV glucose infusions unless necessary (NB: drug infusions) Avoid IV glucose infusions unless necessary (NB: drug infusions) Use insulin to treat hyperglycemia. Use insulin to treat hyperglycemia. Don’t allow a sustained glucose > 250. Don’t allow a sustained glucose > 250. Avoid hypoglycemia and electrolyte abnormalities. Avoid hypoglycemia and electrolyte abnormalities.

Hypothermia in TBI was hot, but now it’s not!Hypothermia in TBI was hot, but now it’s not! National Acute Brain Injury Study: Hypothermia (NABIS:H) National Acute Brain Injury Study: Hypothermia (NABIS:H) = prospective,= prospective,

multicenter, randomized trial multicenter, randomized trial (Clifton GL et al. N Engl J Med 344: 556-63, 2001)(Clifton GL et al. N Engl J Med 344: 556-63, 2001)

“ “Treatment with hypothermia, with the body temperature reaching 33 oC within 8 hours Treatment with hypothermia, with the body temperature reaching 33 oC within 8 hours after injury, was not effective in improving outcomes in patients with severe brain after injury, was not effective in improving outcomes in patients with severe brain injury.”injury.”

Patients that were hypothermic on admission and warmed did poorly. Patients that were hypothermic on admission and warmed did poorly. Patients that were hypothermic on admission and stayed hypothermic seemed to do Patients that were hypothermic on admission and stayed hypothermic seemed to do

better.better. So don’t rewarm hypothermic patients too quickly.So don’t rewarm hypothermic patients too quickly. Bottom line? Bottom line?

Mild induced hypothermia Mild induced hypothermia Not beneficial: Not beneficial:

After traumatic brain injury After traumatic brain injury During clipping of intracranial aneurysms During clipping of intracranial aneurysms (Todd MM et al, New Engl J Med 352: 135-45, 2005.(Todd MM et al, New Engl J Med 352: 135-45, 2005.

Beneficial after successful resuscitation from cardiac arrest Beneficial after successful resuscitation from cardiac arrest (New ACLS Guidelines)(New ACLS Guidelines)

Avoid hyperthermia. Avoid hyperthermia.

Inhaled Anesthetics Inhaled Anesthetics Reasonable maintenance regimens for intracranial neuroanesthesia Reasonable maintenance regimens for intracranial neuroanesthesia

(going(going from routine to desperate) from routine to desperate) N2O + isoflurane (1/2%) + fentanyl? N2O + isoflurane (1/2%) + fentanyl?

N2O = the first agent to go if there’s brain swelling or venous air emboli or N2O = the first agent to go if there’s brain swelling or venous air emboli or danger of ischemia (i.e., danger of ischemia (i.e., head traumahead trauma))

MAC equivalents of sevoflurane or desflurane might also be substituted for MAC equivalents of sevoflurane or desflurane might also be substituted for isofluraneisoflurane

Sufentanil could be substituted for fentanyl. Sufentanil could be substituted for fentanyl. Isoflurane (1%) + fentanyl Isoflurane (1%) + fentanyl Isoflurane (1/2%) + propofol + fentanyl Isoflurane (1/2%) + propofol + fentanyl The volatile agents are next to go if the brain is compromised (i.e. markedly The volatile agents are next to go if the brain is compromised (i.e. markedly

increased ICP or brain swelling). increased ICP or brain swelling). Total IV anesthetic: propofol + fentanyl Total IV anesthetic: propofol + fentanyl Barbiturate coma – for intractable brain swelling (titrated to EEG burst Barbiturate coma – for intractable brain swelling (titrated to EEG burst

suppression)suppression) Thiopental Thiopental Pentobarbital? Pentobarbital?

ICP Monitoring in TBIICP Monitoring in TBI Brain Trauma Foundation Guideline. Brain Trauma Foundation Guideline. ICP monitoring is appropriate in ICP monitoring is appropriate in

severesevere head injury patients (GCS < 8) with an abnormal CT, or a normal CT head injury patients (GCS < 8) with an abnormal CT, or a normal CT scan if 2 or more are noted on admission: scan if 2 or more are noted on admission: Systolic BP < 90 mm Hg Systolic BP < 90 mm Hg Age > 40 years Age > 40 years Uni- or bilateral motor posturing Uni- or bilateral motor posturing

What patients need ICP monitoring during non-neurologic surgery? What patients need ICP monitoring during non-neurologic surgery? (JC(JC Drummond, ASA Refresher Course Lecture 144: 1-7, 2000) Drummond, ASA Refresher Course Lecture 144: 1-7, 2000)

Level of consciousness? If loss of consciousness at any time or GCS < 15, Level of consciousness? If loss of consciousness at any time or GCS < 15, have neurosurgery check CT scan. ICP monitoring is advisable if have neurosurgery check CT scan. ICP monitoring is advisable if compressed basal cisterns, midline shift, effaced ventricles, or any compressed basal cisterns, midline shift, effaced ventricles, or any intracranial lesionintracranial lesion (i.e. contusion, small subdural). (i.e. contusion, small subdural).

Time since injury. Delayed deterioration has been observed up to 48 Time since injury. Delayed deterioration has been observed up to 48 hourspost-injuryhourspost-injury

Intended aortic occlusion, i.e. repair of ruptured aorta Intended aortic occlusion, i.e. repair of ruptured aorta Nature and duration of intended procedure (i.e. short debridement vs. long Nature and duration of intended procedure (i.e. short debridement vs. long

orthopedic procedure)orthopedic procedure)

Summary: ABC’s of Anesthesia for Traumatic Brain InjurySummary: ABC’s of Anesthesia for Traumatic Brain Injury AirwayAirway.. Safely get control.Safely get control. Blood pressure Blood pressure Choose an anesthetic that maintains MAP. Choose an anesthetic that maintains MAP. Avoid hypotension (SBP < 90 mm Hg) if possible, correct it immediately. Avoid hypotension (SBP < 90 mm Hg) if possible, correct it immediately. MAP > 70-80 mm Hg is reasonable. MAP > 70-80 mm Hg is reasonable. Carbon dioxideCarbon dioxide.. Don’t routinely hyperventilate, only if necessary for a “swollenDon’t routinely hyperventilate, only if necessary for a “swollen brain.”brain.” Diuretics or DexamethasoneDiuretics or Dexamethasone?? We usually give diuretics (mannitol). We usually don’t give steroids. We usually give diuretics (mannitol). We usually don’t give steroids. Early decompressive craniectomy Early decompressive craniectomy may cause us many sleepless nights.may cause us many sleepless nights. FluidsFluids.. Avoid hypovolemia.Avoid hypovolemia. GlucoseGlucose.. Treat hyperglycemia.Treat hyperglycemia. Hypothermia Hypothermia was “hot”, but now it’s not. Avoid hyperthermia.was “hot”, but now it’s not. Avoid hyperthermia. IV and Inhaled AnestheticsIV and Inhaled Anesthetics.. N2O is first to go. N2O is first to go. Volatile inhaled anesthetics are next to go. Volatile inhaled anesthetics are next to go. TIVA (with fentanyl and propofol) is reasonable TIVA (with fentanyl and propofol) is reasonable Thiopental (for EEG burst suppression) if intractable brain swelling Thiopental (for EEG burst suppression) if intractable brain swelling

Acute and chronic spinal cord injury Acute and chronic spinal cord injury (SCI) (SCI)

Effects of spinal cord lesions ( Ezekiel MR. Handbook of

Anesthesiology,2002-2003 Edition. Current Clinical Strategies Publishing, pp. 165-66):

LESION SITE COMMON PROBLEM

C3-C5 (Phrenic nerve) Usually apnea requiring intubation and mechanical ventilation

Below C5-C6 Impaired oxygenation and ventilation (up to 70% decrease in VC and FEV1)

T1-T4 (origin of cardio-accelerator fibers) Bradycardia, bradydysrhythmias, AV block, cardiac arrest

Above T7 Significant alveolar ventilation impairment

Issues in spinal cord injury (SCI):Issues in spinal cord injury (SCI): 1. Intubation options: Airway management of acute 1. Intubation options: Airway management of acute

C-spine injury C-spine injury (JC Drummond, ASA Refresher Course Lecture 144: 1-7, 2000)(JC Drummond, ASA Refresher Course Lecture 144: 1-7, 2000)

Rapid sequence induction and intubation with in-line Rapid sequence induction and intubation with in-line cervical fixation cervical fixation

Fiberoptic oral / nasal intubation Fiberoptic oral / nasal intubation Blind nasal intubation (not if basilar skull fracture) Blind nasal intubation (not if basilar skull fracture) Light wand/stylettes Light wand/stylettes Glidescope, Bullard scope, etc. Glidescope, Bullard scope, etc. Retrograde cannulation Retrograde cannulation Laryngeal mask airway (backup for failed intubation) Laryngeal mask airway (backup for failed intubation) CricothyrotomyCricothyrotomy

Succinylcholine

Safe for use in first 24-48 hours

Contraindications to succinylcholine:

AFTER 24-48 HOURS AT ANY TIME

Quadri- or paraplegia Chronic renal failure (K+ > 5.5) Hemiplegia (i.e., stroke) History of malignant hyperthermia (MH) Extensive 3rd degree burns Muscular dystrophy (such as Duchenne’s) Multiple trauma Routine use in pediatrics

3. High-dose methylprednisolone 3. High-dose methylprednisolone (Bracken MB (Bracken MB et alet al, N Engl J Med , N Engl J Med 322:1405-11, 1990)322:1405-11, 1990)

May improve functional recovery if given within 8 hours May improve functional recovery if given within 8 hours after SCI after SCI

Loading dose = 30 mg/kg IV Loading dose = 30 mg/kg IV Maintenance dose = 5.4 mg/kg/hr IV for 23 hours Maintenance dose = 5.4 mg/kg/hr IV for 23 hours

Spinal shock Spinal shock

Spinal shock Spinal shock (Ezekiel MR. Handbook of Anesthesiology, 2002-2003 (Ezekiel MR. Handbook of Anesthesiology, 2002-2003 Edition. Current Clinical Strategies Publishing, pp. 165-66)Edition. Current Clinical Strategies Publishing, pp. 165-66)

Seen in high SCI’s Seen in high SCI’s Lasts a few hours to several weeks Lasts a few hours to several weeks Characterized by (below lesion): Characterized by (below lesion):

Loss of sympathetic tone Loss of sympathetic tone Flaccid paralysis Flaccid paralysis Total absence of visceral and somatic sensation Total absence of visceral and somatic sensation Paralytic ileus Paralytic ileus Loss of spinal cord reflexesLoss of spinal cord reflexes

Autonomic hyperreflexia Autonomic hyperreflexia

Autonomic hyperreflexia Autonomic hyperreflexia (Stoelting RK, Miller RD. Basics of Anesthesia, 4th ed. (Stoelting RK, Miller RD. Basics of Anesthesia, 4th ed. Churchill-Livingstone: 2000, pp. 328-9)Churchill-Livingstone: 2000, pp. 328-9)

A complication of chronic spinal cord transection A complication of chronic spinal cord transection (especially above T6) (especially above T6) Sudden hypertension + reflex bradycardia Sudden hypertension + reflex bradycardia Distension of hollow viscus (e.g. bladder) Distension of hollow viscus (e.g. bladder)

common precipitating event common precipitating event Prevented by spinal anesthesia (also by epidural or general Prevented by spinal anesthesia (also by epidural or general

anesthesia and anti-hypertensives such as nitroprusside anesthesia and anti-hypertensives such as nitroprusside Diagnosis may compel you to insert arterial line Diagnosis may compel you to insert arterial line

Basic Principles of SCI Basic Principles of SCI Difficult airway can be problematic. Difficult airway can be problematic.

Unstable cervical spine. Don’t break the patient’s neck! Unstable cervical spine. Don’t break the patient’s neck! Can’t use succinylcholine after 24-48 hours. Don’t cause Can’t use succinylcholine after 24-48 hours. Don’t cause

a hyperkalemic code! a hyperkalemic code! Hemodynamic instability is common with Hemodynamic instability is common with

anesthesia and surgery. anesthesia and surgery. Acute SCI: spinal shock and hypotension Acute SCI: spinal shock and hypotension Chronic SCI: autonomic hyperreflexia and hypertensionChronic SCI: autonomic hyperreflexia and hypertension

End of End of NeuroAnesthesiologyNeuroAnesthesiology