Head Injuries

In Module 13, we will discuss the assessment and treatment of casualties with suspected head injuries.

Tactical Combat Casualty Care (TCCC) is broken up into 4 roles of care. As a combat medic/corpsman, the first medical provider to care for the casualty and initiate more advanced treatments in the continuum of prehospital care, it is important that you understand the roles and responsibilities of the nonmedical personnel (All Service Members (ASM) and Combat Lifesaver (CLS)) who may be assessing and providing care/assisting in the treatment of casualties with suspected head injuries in the prehospital environment.

There are 5 cognitive learning objectives for this module.

The cognitive learning objectives are: identify external forces that can cause a head injury, identify signs and symptoms of a head injury, identify the indications for performing a Military Acute Concussive Evaluation 2 (MACE 2) for a casualty with a suspected head injury, identify the progressive strategies and constraints for management of a suspected head injury, and identify the signs and symptoms of impending cerebral herniation in the Tactical Field Care (TFC) phase of TCCC.

It is critical for a combat medic/corpsman to recognize casualties with suspected head injuries and to be able to assess and initiate timely treatment and evacuation.

Remember, you are now in TFC which affords the relative safety and time to expand the focus of assessment and management beyond immediate life-threatening hemorrhage control to treatment of other injuries and prevention of potentially life-threatening complications including the prevention and treatment of head injuries.

Keep in mind that the tactical situation is fluid and that the duration of the TFC phase of care could vary from minutes to hours depending on the tactical situation and the availability of evacuation assets.

Assessment and treatment of head injuries is the “H” in the MARCH PAWS sequence (which also includes hypothermia prevention and management).

Head injury is trauma to the SCALP, SKULL, and/or BRAIN.

Scalp injuries may be superficial or associated with an underlying skull and/or brain injury.

Traumatic brain injury (or TBI) may result from either closed or open head injuries.

Closed head injuries, where the skull is not broken, result in TBI; this type of head injury may not be obvious and findings may be very subtle.

In open head injuries, the scalp and skull are broken resulting in a penetrating TBI; these head injuries are typically more obvious.

The mechanism of injury is often your first clue that a casualty may have sustained a head injury. A head injury can be caused by:

- Involvement in a vehicle blast event, collision, or rollover
- Presence within 50 METERS of any blast (inside or outside)
- A direct blow to the head or a fall
- Exposure to more than one blast event
- Gunshot or shrapnel wound to the head, open skull fracture, etc.

Visible wounds of the scalp or obvious deformity or penetrations of the skull noted during the trauma assessment can indicate a conventional or penetrating TBI, which are more obvious and easier to diagnose.

Raccoon eyes or Battle’s sign, which are bruising around the eyes and behind the ears respectively, are signs of a basilar skull fracture.

The leakage of cerebrospinal fluid from the nose (rhinorrhea) or the ears (otorrhea) are other signs that might indicate a skull fracture.

Exposure to blasts and significant impacts from a fall or vehicle crash can lead to head injuries that are not always accompanied by obvious external signs.

Altered mental status may be your first indication of a possible head injury. The initial rapid assessment of a casualty’s mental status comes from communicating with the casualty by asking them to follow commands and to answer questions during the trauma assessment. If the casualty is not responding appropriately (noted by observing their verbal and nonverbal responses), this may be a sign of altered mental status.

Mental status can be further assessed using the AVPU technique. This technique involves assessing for the level of responsiveness by validating whether the casualty is alert (the “A”), responds to your verbal commands appropriately (the “V”), responds to painful stimulation (the “P”), or is unresponsive (the “U”).

Keep in mind that in the combat or trauma setting, altered mental status may be secondary to hypovolemia and/or hypoxia in the presence of other injuries resulting in massive hemorrhage or altered respiratory status.

The IED checklist is an important tool for gathering information and identifying signs and symptoms of a head injury.

I stands for Injury and refers to physical damage to the body or body part of a Service member.

E stands for Evaluation and includes the acronym HEADS, which asks if the casualty has any of the following:

- H – Headaches and/or vomiting?
- E – Ear ringing?
- A – Amnesia, altered consciousness, and/or loss of consciousness?
- D – Double vision and/or dizziness?
- S – Something feels wrong or is not right?

D stands for Distance and asks whether the Service member was within 50 meters of the blast. It is also important to record the approximate distance from the blast.

The severity of TBIs can be identified by the duration of effects.

In Mild TBI (or concussion) symptoms include:

- No or only briefly (a few seconds or minutes up to 30 minutes) loss of consciousness
- Headache, ringing in ears, blurred vision, nausea/vomiting
- Dizziness/lightheadedness, impaired balance/coordination
- Confusion/disorientation and/or memory loss (<24 hours)

In Moderate TBI symptoms are similar to mild TBI but include:

- Confusion or disorientation (>24 hours)
- Loss of consciousness (> 30 minutes but < 24 hours)
- Memory loss (>24 hours but < 7 days)

In Severe TBI symptoms are similar to mild TBI but include:

- Confusion or disorientation (>24 hours)
- Loss of consciousness (> 24 hours)
- Memory loss (>7 days)

Trauma casualties with suspected head injury/TBI due to mechanism, obvious wounds, or proximity to blast event (within 50 meters) should be referred to medical personnel as soon as possible for Military Acute Concussive Evaluation 2 (MACE 2). This evaluation is most effective when done as soon as possible after the injury.

If ANY of the following RED FLAG signs and symptoms are present, MACE 2 should be deferred and urgent evacuation to a higher level of medical care considered:

- Deteriorating level of consciousness
- Double vision
- Increased restlessness; combative or agitated behavior
- Repeat vomiting
- Results from a structural brain injury detection device (if available)
- Seizures
- Weakness or tingling in the arms or legs
- Severe or worsening headache

Casualties with an altered mental status due to head injury often act (and react) inappropriately and can be a potential danger to themselves, first responders, and their unit and mission.

First responders and medical personnel must recognize when a casualty has an altered mental status and take steps to disarm the casualty and secure any communication equipment they may be carrying.

Casualties are likely to resist this but will usually respond to reassurance that you are securing their equipment while you evaluate and care for them and that their unit will take responsibility for it.

Treatment for the casualty with a suspected head injury/TBI should be initiated as soon as possible following acute injury with the goal of preventing secondary brain injury caused by hypoxia and hypotension.

Treatment should include the following:

- Control hemorrhage from head and other injuries
- Administer tranexamic acid as indicated per TCCC guidelines
- Secure airway as indicated
- Provide supplemental oxygen if available (monitor with pulse oximetry and maintain oxygen saturation >90%)
- Resuscitate as indicated (monitor and maintain normal radial pulse or, if blood pressure monitoring is available, systolic blood pressure 100-110 mm Hg)
- Treat other immediately life-threatening injuries to prevent hypoxia and hypotension (secondary brain injury)
- Prevent/treat hypothermia
- Administer antibiotics for all open wounds per TCCC guidelines
- Manage pain per TCCC guidelines; TBI does NOT preclude use of ketamine or fentanyl, but caution should be used when administering in casualties suspected of TBI as it may make it difficult to assess mental status, perform a neurologic exam, or determine if casualty is decompensating

More advanced treatments and interventions for head injury/TBI are addressed in the Tactical Evacuation (TACEVAC) phase of TCCC.

Brain herniation is a potentially deadly side effect of moderate/severe TBI that occurs when a part of the brain is squeezed across the fixed structures within the skull, through a defect in the skull (from an open skull fracture or penetrating wound), or through the hole in the base of the skull where the spinal cord connects with the brain.

In the combat or trauma setting, herniation can result due to mass effect from intracranial bleeding or increased intracranial pressure caused by swelling associated with TBI.

Brain herniation typically presents with one or more of the following signs and symptoms:

-Abnormal body posturing, a characteristic positioning of the limbs indicative of severe brain damage

-Decreased level of consciousness

-One or both pupils may be dilated (i.e., blown) and fixed (i.e., fail to constrict in response to light)

-Vomiting

-Severe headaches

-Seizures

-Cardiovascular and respiratory symptoms including respiratory depression, hypertension, and bradycardia (Cushing’s sign)

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Signs of impending brain herniation must be addressed as soon as possible and are an indication for urgent evacuation to a higher level of medical care.

More advanced treatments and interventions are addressed in the TACEVAC phase of TCCC.

Unilateral pupillary dilation accompanied by a decreased level of consciousness may signify impending cerebral herniation; if these signs occur, take the following actions to decrease intracranial pressure:

- Administer 250 ml of 3 or 5% hypertonic saline IV/IO bolus.

OR

- Give 30 mL 23.4% hypertonic saline SLOW IV/IO push over 10 minutes followed by a saline flush. Repeat in 20 minutes if no response (max 2 doses). Monitor IV site and discontinue if signs of extravasation.
- Elevate the casualty’s head 30 degrees if patient is not in shock and tactically feasible.
- Hyperventilate the casualty.
- Hyperventilate at 20 breaths per minute.
- Capnography should be used to maintain the end-tidal CO2 between 32-38 mmHg.
- The highest oxygen concentration (FIO2) possible should be used for hyperventilation.
- Do not hyperventilate the casualty unless signs of impending herniation are present. Casualties may be hyperventilated with oxygen using the bag-valve-mask technique.

Casualties with moderate/severe TBI should be monitored for:

- Decreases in level of consciousness
- Pupillary dilation
- SBP should be >90 mmHg
- O2 sat > 90
- Hypothermia
- End-tidal CO2 (If capnography is available, maintain between 32-38 mmHg)
- Penetrating head trauma (if present, administer antibiotics)
- Assume a spinal (neck) injury until cleared.

Head injury is defined as trauma to the scalp, skull, or brain.

Mechanisms of injury include motor vehicle accidents, blast events, falls, or a blow or gunshot/shrapnel wound to the head.

Signs and symptoms typically include obvious wounds to the scalp or skull, raccoon eyes/Battle’s sign, CSF otorrhea/ rhinorrhea, altered or loss of consciousness, headache, visual changes, ringing in ears, nausea/vomiting, dizziness, impaired balance/coordination, amnesia, etc.

Casualties with suspected head injury/TBI should be referred to medical personnel for MACE 2 evaluation.

Management of suspected head injury/TBI in TFC is focused on preventing secondary brain injury due to hypoxia and hypotension.

Although not treated in TFC, it is important to be able to identify signs and symptoms of impending cerebral herniation requiring urgent evacuation to a higher level of medical care.

# Answers

### What external forces can cause a head injury?

- Involvement in a vehicle blast event, collision, or rollover
- The presence within 50 METERS of a blast (inside or outside)
- A direct blow to the head or a fall
- Gunshot or shrapnel wound to the head, open skull fracture, or witnessed loss of consciousness
- Exposure to more than one blast event (the Service member’s commander will direct a medical evaluation)

### What are the critical observations or red flags that may prompt urgent evacuation to a higher level of medical care for trauma casualties with a suspected head injury, in accordance with the Military Acute Concussive Evaluation 2 (MACE 2)?

- Deteriorating level of consciousness
- Double vision
- Increased restlessness; combative or agitated behavior
- Repeat vomiting
- Results from a structural brain injury detection device (if available)
- Seizures
- Weakness or tingling in arms or legs
- Severe or worsening headache

### What is the goal of management for casualties with suspected head injuries/TBI in TFC?

Prevention of secondary brain injury from hypotension and hypoxia.