Download MBBS (Bachelor of Medicine, Bachelor of Surgery) Neuroanaesthesia PPT 5 Perioperative Management Of Traumatic Brain Injury Lecture Notes
Perioperative Management of
Traumatic Brain Injury
Introduction
? "a blow to head or a penetrating head injury
that disrupts the function of brain"
? One lakh lives are lost every year due to TBI in
India
? Nearly 95% trauma victims do not receive
optimal care during `Golden Hour' period
? Among them 30% of lives could be saved if
quality care were available to them sooner
Global data on TBI
? 50 million injured every year
? Estimated deaths ? 1.2 million
? Global mortality: 97/1,000,000
? 70 % fatalities (8,500,000) under 45 years of age
? WHO Research Predicts by 2020:
? 80 % increase in developing countries
? 147 % increase in road traffic accidents (RTA)
deaths in India/Rajasthan
Indian data on TBI
? 60% of all TBI caused by RTA
? Fatality rate: 70 per 10,000 vehicles
? 25X higher than in developed countries
? One person dies in India every 6 - 10 mins; will
be every 3 mins by 2020
? "vulnerable road users":
- Pedestrians (25 %),
- Motorcyclists (17 %),
- Four-wheel vehicle operators (15%),
- Pedal cyclists (10 %).
? By 2050, India will have the greatest number
of automobiles on the planet, overtaking the
United States.
? A study conducted by CRRI-
? Increase traffic congestion in Delhi might
actually have resulted in fewer accidents over
last year.
Pathophysiology of Traumatic Brain Injury
TBI
10 Injury to brain
ICP
Inlammation/edema/excitotoxicity
ICP CPP
Secondary injuries to brain
Secondary insults contributing to
hypoxic/ ischemic brain damage
Systemic
intracranial
Hypoxemia
Hematoma
Hypotension
Raised ICP
Anemia
Seizures
Hypo/hyper carbia
Infection
Pyrexia
Vasospasm
Hyponatremia
Hypo/hyper glycemia
Importance of perioperative period
? Most of the poor outcomes after severe head injury
are related to presence of pre-hospital secondary
insults
? Perioperative period provides an opportunity to
continue and refine ongoing resuscitation and to
correct pre-existing secondary insults
? Perioperative period may be a window to initiate
interventions, that may improve the outcome of TBI
Does the "Golden Hour" After Injury
Really Matter?
Golden hour
? A traditional dogma- trauma patients should
reach the hospital and to be treated with in one
hour of injury
? First described by R Adams Cowley in 1975
? Several studies have suggested a decrease in
mortality when trauma patients reach definitive
care during the Golden Hour, but recent research
demonstrates no link between time and survival.
? Although prehospital time should be minimized, the
use of lights and sirens and air transport entail costs
and risks that must be weighed against possible
benefit for each patient.
? Also, for really seriously injured patients, arrival at
the right place (a Level I trauma center) is probably
much more important than the out-of-hospital time.
- Newgard CD et al. Ann Emerg Med 2015 Jan 14.
Goals of perioperative management of
TBI
? The key elements of TBI management-
?Early resuscitation
?Hemodynamic optimization
?Emergent surgical evacuation of mass lesion
?Control of ICP
?Support of CPP
?Optimization of physiological milieu
Prehospital Management
? Emergency therapy should begin at the site of
accident and in the ambulance
? EMS providers- should be trained to follow an
established algorithm for assessment and
treatment of TBI
? The first priority is initiation of basic
resuscitation protocol, prioritizing the ABCs
? Severely head injured patient to be directly
taken to level I trauma centre- BTF
Emergency Department Management
? The initial assessment and stabilization-
achieved as soon as the pt arrives in the ED
? Evaluation of ABCs
?Rapid assessment of neurological status,
pupillary response
?Associated extra cranial injuries
?Evaluation of anemia/ coagulopathy/ glycemia
?Adequate vascular access
? Non contrast CT scan is radiological procedure
of choice
Airway management
? Airway management in TBI is complicated-
? urgency of situation
?Uncertainty of cervical spine status
?Uncertainty of airway
?Full stomach
?Intracranial hypertension
?Uncertain volume status
Technique - Best Practices
? Choice of technique depends upon-
?Urgency /Individual expertise/ Available
resources
? Generally incorporates RSI with cricoid pressure
and MILS
? Newer airway devises, particularly
videolaryngoscopes, may be useful in difficult
airway scenarios
? Nasal intubation- avoided in patients with base of
skull fracture, severe facial fractures or bleeding
diathesis.
? Appropriate pharmacological selection is
important
? Sodium thiopental, etomidate and propofol
decrease cerebral metabolic rate for oxygen
(CMRO2) and attenuate increases in ICP with
intubation
? Propofol & Thiopental may cause CVS depression
leading to hypotension
? Etomidate- hemodynamic stability during
induction? Adrenal insufficiency
? The choice of muscle relaxant for RSI is
succinylcholine or rocuronium
? Succinylcholine may contribute to increased ICP
the clinical significance?
Anesthetic Management
? The major goals of anesthetic management of
TBI are-
?To facilitate early decompression
?Provide adequate analgesia and amnesia
?Treat intracranial hypertension and maintain
adequate cerebral perfusion
?Provide optimal surgical conditions
?Avoid secondary insults
Anesthetic technique
? IV or volatile anaesthetic agents??
? There is little evidence to support the use of
one over the other
? All volatile agents reduce CMRO2, produce
cerebral vasodilatation- resulting in increased
CBF and ICP.
? However, at concentrations up to 1 MAC these
effects are minimal
? Sevoflurane appears to have the best profile.
? N2O is best avoided
? I.V. agents reduce CMRO2, CBF, and ICP.
? Neuromuscular drugs are recommended to
prevent coughing or straining
Ventilation
? Ventilation should be adjusted to ensure adequate
oxygenation (PaO2 > 60 mmHg) and normocarbia
(PaCO2 35-45 mmHg).
? Monitoring arterial PaCO2 is recommended
? Hypercarbia (PaCO2 > 45 mmHg) to be avoided
? Hyperventilation should be used judiciously for
short-term control of ICP
? Excessive and prolonged hyperventilation may
cause cerebral vasoconstriction leading to
ischemia
Monitoring
? Multimodal monitoring
? American Society of Anesthesiology (ASA)
monitors
? Arterial catheterization is recommended for
continuous BP monitoring, ABG and glucose
monitoring in patients who require surgical
intervention
? ICP monitoring is recommended in all
salvageable patients with a severe TBI (GCS <
9) and an abnormal CT scan
? Jugular venous oximetry is often useful for
assessment of adequacy of global cerebral
oxygenation
? Brain tissue oxygen monitors have the
advantage of identifying focal areas of
ischemia which may not be picked up by
jugular venous oximetry.
? Near Infrared Spectroscopy (NIRS) offers the
capacity to conveniently and non-invasively
monitor cerebral oxygen in the intensive care
unit.
? Transcranial Doppler (TCD) ultrasonography
is a non-invasive, nonradioactive, bedside
monitor, which can provide useful
instantaneous cerebrovascular information
including changes in cerebral blood flow
velocity, cerebral vasospasm and
autoregulation
Intravenous Fluids, Blood Pressure
Management and Vasopressor Use
? BP management, including choice of fluids and
vasopressors, is of paramount importance
? BTF guidelines for the management of TBI recommend
avoiding hypotension (SBP < 90 mmHg) and
maintaining CPP between 50 and 70mmHg.
? Perioperative hypotension should be treated promptly
? Hypertonic saline may be beneficial resuscitation fluid
for TBI patients
? Current evidence does not support preference of one
vasopressor over the other to support cerebral perfusion
and the choice may have to be individualized to patient
characteristics
Coagulopathy
? Coagulation disorders may be present in
approximately one-third TBI patients and is
associated with an increased mortality and
poor outcome
? Brain injury leads to the release of tissue factor.
? Patients with GCS 8, associated cerebral
edema, SAH and midline shift are likely to
have coagulopathy
Hyperosmolar therapy
? Mannitol is commonly used for hyperosmolar
therapy
? The recommended dose of mannitol is 0.25-1
g/kg body weight
? In patients with severe TBI and elevated ICP
refractory to mannitol treatment, 7.5%
hypertonic saline administered as second tier
therapy
Glycemic Control
? Hyperglycemia after TBI is associated with
increased morbidity and mortality
? Hyperglycemia can cause secondary brain
injury
? Hypoglycemeia is equally deleterious to brain
? Given the current evidence for glucose control
for TBI in perioperative period, a target
glucose range of 80-180 mg/dl is reasonable
Therapeutic Hypothermia and Steroids
? Hypothermia reduces cerebral metabolism during
stress, reduces excitatory neurotransmitters
release, attenuates BBB permeability
? Yet, clinical evidence in terms of mortality and
functional outcomes is still inconclusive.
? Accordingly, the BTF/AANS guidelines task
force has issued a Level III recommendation for
optional and cautious use of hypothermia for
adults with TBI
This post was last modified on 07 April 2022