Chapter 22 Traumatic Brain Injury (Direct Text)

Question 1

INTRODUCTION AND EPIDEMIOLOGY:
TBI is a serious public health problem in the United States.
Each year, an estimated 1.7 million people sustain a TBI. Of them 52,000 die, 275,000 are hospitalized, and 1.365 million, nearly 80%, are treated and released from an emergency department.
TBI is responsible for a third (30.5%) of _________ injury-related deaths in the United States.
TBI is more common in children aged 0 to 4 years, adolescents aged 15 to 19 years, and adults aged 65 years and older. Adults aged _________ years and older have the highest rates of TBI-related hospitalization and death. TBI rates are higher for males than for females.

Answer 1

INTRODUCTION AND EPIDEMIOLOGY:
TBI is a serious public health problem in the United States.
Each year, an estimated 1.7 million people sustain a TBI. Of them 52,000 die, 275,000 are hospitalized, and 1.365 million, nearly 80%, are treated and released from an emergency department.
TBI is responsible for a third (30.5%) of all injury-related deaths in the United States.
TBI is more common in children aged 0 to 4 years, adolescents aged 15 to 19 years, and adults aged 65 years and older. Adults aged 75 years and older have the highest rates of TBI-related hospitalization and death. TBI rates are higher for males than for females.

Question 2

The leading causes of TBI are
\_\_\_\_\_\_\_\_\_ (35.2%);
\_\_\_\_\_\_\_\_\_ \_\_\_\_\_\_\_\_\_ – traffic (17.3%);
struck by/against events (16.5%); and
\_\_\_\_\_\_\_\_\_ (10%).
Blasts are a leading cause of TBI for military personnel in war zones.

Answer 2

The leading causes of TBI are
falls (35.2%);
motor vehicle – traffic (17.3%);
struck by/against events (16.5%); and
assaults (10%).
Blasts are a leading cause of TBI for military personnel in war zones.

Question 3

Direct medical costs and indirect costs such as lost productivity because of TBI totaled an estimated $_________ billion in the United States in 2000.

Answer 3

Direct medical costs and indirect costs such as lost productivity because of TBI totaled an estimated $60 billion in the United States in 2000.

Question 4

Primary injury occurs at the time of impact and results from the _________ forces of the impact (Fig. 22-1).
Secondary injury follows primary injury and is the effect of cerebral and extracerebral insults. It occurs at both a macroscopic level and a cellular level.

Answer 4

Primary injury occurs at the time of impact and results from the shear forces of the impact (Fig. 22-1).
Secondary injury follows primary injury and is the effect of cerebral and extracerebral insults. It occurs at both a macroscopic level and a cellular level.

Question 5

The mechanisms of secondary injury are classified under four categories (Table 22-1):
_________, _________, energy failure, and cell death.
_________ swelling.
_________ injury.
_________ and regeneration.

Answer 5

The mechanisms of secondary injury are classified under four categories (Table 22-1):
Ischemia, excitotoxicity, energy failure, and cell death.
Cerebral swelling.
Axonal injury.
Inflammation and regeneration.

Question 6

Theories of Recovery:
At least three different theories have been proposed to explain the recovery that follows a brain injury and include a reversal of _________, _________, and adaptive _________.

Answer 6

Theories of Recovery:
At least three different theories have been proposed to explain the recovery that follows a brain injury and include a reversal of diaschisis, compensation, and adaptive plasticity.

Question 7

Diaschisis is a temporary reduction in function of structures interconnected with an injured brain. Functional recovery is likely to be related to a gradual _________ in diaschisis.
Compensation is the use of _________ strategies as an individual attempts to supplement lost function.
A third theory is that functional recovery is largely dependent upon neuroplasticity of intact remaining brain structure. Underlying mechanisms include _________ of existing connections, long-term _________, long-term _________, _________ sprouting, dendritic sprouting, synaptogenesis, and angiogenesis (Table 22-2).

Answer 7

Diaschisis is a temporary reduction in function of structures interconnected with an injured brain. Functional recovery is likely to be related to a gradual reduction in diaschisis.
Compensation is the use of alternative strategies as an individual attempts to supplement lost function.
A third theory is that functional recovery is largely dependent upon neuroplasticity of intact remaining brain structure. Underlying mechanisms include unmasking of existing connections, long-term potentiation, long-term depression, axonal sprouting, dendritic sprouting, synaptogenesis, and angiogenesis (Table 22-2).

Question 8

Glasgow Outcome Scale: The Glasgow Outcome Scale (GOS) is a five-level score:

1. _________.
2. _________ state.
3. _________ disabled.
4. _________ disabled.
5. Good recovery.

Answer 8

Glasgow Outcome Scale: The Glasgow Outcome Scale (GOS) is a five-level score:

1. Dead.
2. Vegetative state.
3. Severely disabled.
4. Moderately disabled.
5. Good recovery.

Question 9

Posttraumatic Amnesia (PTA): the duration during which patients neither encode nor retain any new information and experience and can be assessed by _________ _________ _________ Test (_________). The end of PTA is marked by a score of > _________ on _________ on _________ _________ days (Table 22-3). In the future, a combination of clinical, laboratory (serum biomarkers and genetic markers), evoked potentials, and radiological techniques (functional MRI and MR spectroscopy) may need to be used for prognostication (Table 22-4).

Answer 9

Posttraumatic Amnesia (PTA): the duration during which patients neither encode nor retain any new information and experience and can be assessed by Galveston Orientation Amnesia Test (GOAT). The end of PTA is marked by a score of >75 on GOAT on two consecutive days (Table 22-3). In the future, a combination of clinical, laboratory (serum biomarkers and genetic markers), evoked potentials, and radiological techniques (functional MRI and MR spectroscopy) may need to be used for prognostication (Table 22-4).

Question 10

ACUTE TREATMENT
The “ABCs,” _________ maintenance, _________, and _________, are addressed first. The spine is immobilized due to a risk of associated cervical spine injury.

Answer 10

ACUTE TREATMENT
The “ABCs,” airway maintenance, breathing, and circulation, are addressed first. The spine is immobilized due to a risk of associated cervical spine injury.

Question 11

Intracranial Pressure (ICP) Monitoring in Severe TBI: ICP monitoring is appropriate in:

1. Patients with Glasgow Coma Scale scores postresuscitation ≤ _________.
2. Head CT showing _________, _________, _________, or compressed basilar cisterns.
3. ICP monitoring may also be appropriate in patients with postresuscitation scores ≤ _________ with a normal head CT and two of the following: age > _________ years, motor posturing, or a systolic pressure of

Answer 11

Intracranial Pressure (ICP) Monitoring in Severe TBI: ICP monitoring is appropriate in:

1. Patients with Glasgow Coma Scale scores postresuscitation ≤8.
2. Head CT showing contusions, hemorrhages, edema, or compressed basilar cisterns.
3. ICP monitoring may also be appropriate in patients with postresuscitation scores ≤8 with a normal head CT and two of the following: age >40 years, motor posturing, or a systolic pressure of

Question 12

ICP is monitored by external _________ drain that can both monitor and drain CSF if necessary. Increased ICPs can be managed by elevating the head end of the bed, preventing _________, and using diuretics like _________. Additional modalities may include use of hyperventilation, barbiturates, and decompressive hemicraniectomy. _________ have not been shown to reduce ICP and are not recommended for use in TBI.

Answer 12

ICP is monitored by external ventricular drain that can both monitor and drain CSF if necessary. Increased ICPs can be managed by elevating the head end of the bed, preventing hyperthermia, and using diuretics like mannitol. Additional modalities may include use of hyperventilation, barbiturates, and decompressive hemicraniectomy. Steroids have not been shown to reduce ICP and are not recommended for use in TBI.

Question 13

Use of hypothermia has _________ shown to reduce all-cause mortality. Brain Trauma Foundation recommendations (Guidelines for the management of severe TBI, 3rd edition, 2007) do not show any level 1 or level 2 evidence for use of hypothermia. However, patients treated with hypothermia were more likely to have a neurological favorable outcome of GOS 4 or 5.

Answer 13

Use of hypothermia has not shown to reduce all-cause mortality. Brain Trauma Foundation recommendations (Guidelines for the management of severe TBI, 3rd edition, 2007) do not show any level 1 or level 2 evidence for use of hypothermia. However, patients treated with hypothermia were more likely to have a neurological favorable outcome of GOS 4 or 5.

Question 14

Issues Unique to TBI
Sleep Disturbances – Sleep disturbances occur commonly in patients who have suffered a TBI and may occur during all stages of recovery. Establishing an adequate _________–_________ cycle plays a vital role. Nonpharmacological and pharmacological techniques may need to be utilized. Medications for sleep initiation and for sleep maintenance may need to be considered.

Answer 14

Issues Unique to TBI
Sleep Disturbances – Sleep disturbances occur commonly in patients who have suffered a TBI and may occur during all stages of recovery. Establishing an adequate sleep–wake cycle plays a vital role. Nonpharmacological and pharmacological techniques may need to be utilized. Medications for sleep initiation and for sleep maintenance may need to be considered.

Question 15

Pharmacotherapy of Arousal and Alertness
Dopaminergic agents (\_\_\_\_\_\_\_\_\_ and \_\_\_\_\_\_\_\_\_) and adrenergic agents like methylphenidate are considered in issues related to impaired arousal and alertness.

Answer 15

Pharmacotherapy of Arousal and Alertness
Dopaminergic agents (amantadine and bromocriptine) and adrenergic agents like methylphenidate are considered in issues related to impaired arousal and alertness.

Question 16

Agitation – Posttraumatic agitation is defined as a delirium present during the period of PTA, manifested by behavioral excesses such as _________, _________, _________, emotional lability, destructiveness, or combativeness.

Answer 16

Agitation – Posttraumatic agitation is defined as a delirium present during the period of PTA, manifested by behavioral excesses such as aggression, akathisia, disinhibition, emotional lability, destructiveness, or combativeness.

Question 17

The Agitated Behavior Scale is commonly used to quantify agitation in the rehabilitation setting. Medical reasons are always considered first (_________, _________, _________, and metabolic abnormalities). Treatment includes nonpharmacological interventions (quiet room, dim light, limited visitors, Vail bed, and ambulation). Atypical antipsychotics are considered an option in managing TBI-related agitation. Cochrane database review reported that the best evidence for medication management in the treatment of TBI-related agitation exists for _________ (_________) (2003).

Answer 17

The Agitated Behavior Scale is commonly used to quantify agitation in the rehabilitation setting. Medical reasons are always considered first (infections, pain, hypoxia, and metabolic abnormalities). Treatment includes nonpharmacological interventions (quiet room, dim light, limited visitors, Vail bed, and ambulation). Atypical antipsychotics are considered an option in managing TBI-related agitation. Cochrane database review reported that the best evidence for medication management in the treatment of TBI-related agitation exists for inderal (Propranolol) (2003).

Question 18

Endocrine Dysfunction after TBI – Approximately 30% to 50% of patients who survive a TBI demonstrate endocrine abnormalities. _________ _________ _________ _________ _________ is the common TBI endocrinopathy causing hyponatremia and is associated with euvolemia, low BUN, and urine osmolality greater than serum osmolality. The treatment in most cases is fluid restriction and in rare cases hypertonic saline.

Answer 18

Endocrine Dysfunction after TBI – Approximately 30% to 50% of patients who survive a TBI demonstrate endocrine abnormalities. Syndrome of Inappropriate Antidiuretic Hormone is the common TBI endocrinopathy causing hyponatremia and is associated with euvolemia, low BUN, and urine osmolality greater than serum osmolality. The treatment in most cases is fluid restriction and in rare cases hypertonic saline.

Question 19

A less common cause of hyponatremia is _________ _________ _________ where patients are dehydrated. Hence, treatment includes replacement of fluids and salt.

Answer 19

A less common cause of hyponatremia is cerebral salt wasting where patients are dehydrated. Hence, treatment includes replacement of fluids and salt.

Question 20

_________ _________ is rare and usual onset is 5 to 10 days after trauma. Features include polyuria, low urine osmolality, high serum osmolality, and normal to high sodium. Treatment includes hormonal replacement. Anterior hypopituitarism may present weeks to _________ after moderate to severe TBI and may have an insidious onset with _________, _________, bradycardia, hypotension, hyponatremia, or stagnation of rehabilitation progress. Workup includes serum hormonal assays and treatment includes hormonal replacement.

Answer 20

Diabetes insipidus is rare and usual onset is 5 to 10 days after trauma. Features include polyuria, low urine osmolality, high serum osmolality, and normal to high sodium. Treatment includes hormonal replacement. Anterior hypopituitarism may present weeks to months after moderate to severe TBI and may have an insidious onset with malaise, hypothermia, bradycardia, hypotension, hyponatremia, or stagnation of rehabilitation progress. Workup includes serum hormonal assays and treatment includes hormonal replacement.

Question 21

Dysautonomia – manifests as _________, increased _________, _________, fever, and sweating. Treatment options include NSAIDs, β-blockers, and symptomatic treatment.

Answer 21

Dysautonomia – manifests as tachycardia, increased BP, tachypnea, fever, and sweating. Treatment options include NSAIDs, β-blockers, and symptomatic treatment.

Question 22

Posttraumatic Epilepsy (PTE) – a disorder characterized by recurrent _________ seizure episodes in patients with TBI, not attributable to any other etiology. _________ and _________ acid are the preferred agents for treatment of PTE, and treatment duration is not clearly established.

Answer 22

Posttraumatic Epilepsy (PTE) – a disorder characterized by recurrent late seizure episodes in patients with TBI, not attributable to any other etiology. Carbamazepine and valproic acid are the preferred agents for treatment of PTE, and treatment duration is not clearly established.

Question 23

Posttraumatic seizures (PTS) refer to a single or recurrent seizure episode after TBI. PTS have further been classified as early (1 week after TBI).8 The incidence of early seizures is approximately 5% among nonpenetrating TBI patients and is higher in younger children and that of late seizures is 4% to 7% in nonpenetrating TBI. PTS are observed in 35% to 65% of patients with penetrating TBI. Studies do not recommend the use of prophylactic anticonvulsants for the prevention of late PTS. Routine seizure prophylaxis beyond 1 week after TBI is not recommended. Prophylactic _________ has been shown to reduce the risk of early seizures after severe TBI, but no benefit has been found between 8th day and 2 years post-TBI. Prophylactic use of _________ or _________ is not recommended to prevent late PTS, and treatment duration is not clearly established.

Answer 23

Posttraumatic seizures (PTS) refer to a single or recurrent seizure episode after TBI. PTS have further been classified as early (1 week after TBI).8 The incidence of early seizures is approximately 5% among nonpenetrating TBI patients and is higher in younger children and that of late seizures is 4% to 7% in nonpenetrating TBI. PTS are observed in 35% to 65% of patients with penetrating TBI. Studies do not recommend the use of prophylactic anticonvulsants for the prevention of late PTS. Routine seizure prophylaxis beyond 1 week after TBI is not recommended. Prophylactic phenytoin has been shown to reduce the risk of early seizures after severe TBI, but no benefit has been found between 8th day and 2 years post-TBI. Prophylactic use of phenytoin or valproate is not recommended to prevent late PTS, and treatment duration is not clearly established.

Question 24

Role of Technology in Rehabilitation of TBI Patients – Use of virtual reality (for driving simulation and to simulate real-life scenarios), as these sessions have been shown to facilitate _________ and promote motor recovery. Neuroprosthetics to improve ambulation and robotic trainers to maximize therapy intensity and make mass practice more convenient.
No evidence exists to recommend the use of hyperbaric oxygen therapy in the treatment of TBI.

Answer 24

Role of Technology in Rehabilitation of TBI Patients – Use of virtual reality (for driving simulation and to simulate real-life scenarios), as these sessions have been shown to facilitate neuroplasticity and promote motor recovery. Neuroprosthetics to improve ambulation and robotic trainers to maximize therapy intensity and make mass practice more convenient.
No evidence exists to recommend the use of hyperbaric oxygen therapy in the treatment of TBI.