What is Closed Head Trauma?
Traumatic brain injury, often referred to as TBI, is when the brain is harmed by an external physical force. Typically, TBI comes in two forms, either closed or penetrating. The latter involves a break in the skull and the outer layer of the brain, but closed head injuries are a lot more common. There’s a variety of closed head injuries, including concussion, contusion, widespread nerve damage, and different types of bleeding inside the skull. This discussion will concentrate on closed head injuries, interchanging the terms TBI and closed head injury.
TBI gets categorized into mild, moderate, or severe using the Glasgow Coma Scale (GCS). Mild TBI, often known as a “concussion,” is marked by a GCS of 14 to 15 and represents over 80% of TBIs. Moderate TBI, indicated by a GCS of 9 to 13, makes up about 10% of TBIs. Severe TBI, marked by a GCS of 3 to 8, is the most serious form.
What Causes Closed Head Trauma?
The main reason why people get cranial head injuries (CHI) is because of falls, which make up over 35% of these cases. Other common causes include car accidents and traffic-related injuries. Violence, workplace accidents, and sports injuries can also cause cranial head injuries.
Evaluating a person with CHI should involve the consideration of non-accidental harm like elder abuse and domestic violence as these could also be potential reasons behind the injury.
Risk Factors and Frequency for Closed Head Trauma
CHI, or Closed Head Injury, happens more frequently in men compared to women in all ages. For children aged 0 to 14 years old and adults who are 65 years or older, over half of the Traumatic Brain Injuries (TBIs) are caused by falls. However, for children 0 to 14 years old, the second most frequent reason for a TBI is getting hit by or striking against something. In other age groups, the second leading cause is accidents involving motor vehicles or traffic incidents. Globally, more than 30% of all trauma deaths are due to TBI.
- CHI happens more frequently in men than women across all ages.
- Falls are the biggest cause of TBIs in children 0 to 14 years old and adults who are 65 years and older.
- For children aged 0 to 14, getting hit by or striking against something is the second main cause of TBIs.
- In other age groups, the second chief cause of TBIs are accidents related to motor vehicles or traffic.
- Around the world, TBIs account for more than 30% of all trauma related deaths.
Signs and Symptoms of Closed Head Trauma
When dealing with patients who have experienced severe trauma, medical professionals follow the Advanced Trauma Life Support (ATLS) protocol. They gather any available information about the incident, such as how it happened, whether there were any immediate changes like seizures or vomiting, and whether any drugs or existing health conditions might complicate the situation. These details could come from emergency medical services, the patient (if they can communicate effectively), family members, or witnesses.
A core part of assessing these patients is measuring their Glasgow Coma Scale (GCS), which determines their level of consciousness. It rates their eye-opening, verbal, and physical responses, resulting in a score between 1 and 15. This score will be tracked throughout their hospital stay to observe any changes in the patient’s state. During a physical examination, medical professionals will watch for signs that suggest brain injury. For example, having one pupil larger and unresponsive could point to particular types of brain herniation, and not being able to move the upper or lower limbs on command or in response to pain might show severe brain injury.
In patients that are unconscious, professionals can test their brainstem reflexes, checking their respiratory pattern and their pupillary, corneal, cough, and gag reflexes. All these help diagnose the injury and predict the outcome.
- Continual monitoring is essential because any changes might indicate increasing intracranial pressure (ICP) or brain herniation, which are critical complications.
- Indicators of increased ICP include high blood pressure, a slow heart rate, abnormal respirations, severe headache, changes in vision, nausea, vomiting, lethargy, localized weakness or numbness, or unconsciousness.
- Signs of possible brain shift or herniation include worsening neurological condition, pupils dilating (either in one eye or both), muscle paralysis on one side or abnormal positioning of the body.
Testing for Closed Head Trauma
If there’s a possibility that a patient has severe brain trauma, doctors typically use CT (Computed Tomography) scans because they are extremely effective in detecting any acute internal brain bleeding. The goal is to get these scans done as quickly and safely as possible. However, to avoid unnecessary CT scans, doctors have decision-making rules that help them determine which patients with traumatic brain injuries need a head CT scan. These rules are mainly designed to spot patients who might need neurosurgery. It’s important to note that these rules don’t identify patients who may experience short or long-term neurological effects from their brain injury.
Two popular decision-making rules used for adults are the Canadian Head CT Rule and the New Orleans Criteria. Both are 100% effective in identifying significant trauma-related internal brain injuries, but the Canadian Head CT Rule is more precise. Patients who are on blood thinners were not included in the studies for these rules.
For patients under 18 years old, doctors often use the PECARN Pediatric Head Injury/Trauma Algorithm. This tool is also nearly 100% effective in identifying significant internal brain injuries.
Doctors also often consider doing C-spine imaging, particularly for patients in a coma. Meanwhile, MRI (Magnetic Resonance Imaging) can be used to detect less obvious injuries that a CT scan might not pick up, or to give a better definition of those injuries identified in a CT scan. However, as MRI can be hard to obtain and hasn’t shown much value in the initial assessment of acute cranial injuries, it’s not a regular part of the initial evaluation. Still, it can provide more information about long-term bleeding.
Treatment Options for Closed Head Trauma
The initial focus when treating a severe brain injury (TBI) is to make sure the patient’s airways are open, they’re breathing properly, and their circulation is functioning well – the ABCs. These are important to ensure both oxygen and blood continue to flow to the brain.
If the patient has a Glasgow Coma Scale (GCS) score of 8 or less, they’ll likely need a tube inserted into their airway to ensure they can breathe properly. A rapid sequence intubation is generally conducted, using medication that won’t affect the patient’s blood pressure or the pressure inside their skull too much. There’s ongoing debate about whether a drug called ketamine can be safely used for this. For muscle paralysis during intubation, succinylcholine and rocuronium have been deemed safe and effective. It’s also important to avoid nasal intubation if a patient has suspected facial or skull injuries.
As for the patient’s breathing, the aim is to maintain normal oxygen levels. Evidence suggests that a low oxygen level is linked to higher mortality rates. For circulation, the focus is on maintaining enough blood and oxygen supply to the brain. Keeping the blood pressure high and the pressure within the skull low helps to achieve this. Fluid resuscitation might be initiated to maintain adequate blood pressure.
The patient’s bed might also be elevated to 30 degrees if there’s a suspected increase in the pressure within their skull, although it’s still unclear if this is really beneficial. Keeping the patient’s blood sugar levels within an acceptable range is also recommended, which might require an insulin drip in serious TBI cases.
In terms of temperature, a fever can increase the brain’s metabolic demands and possibly enhance the pressure within the skull, so it should be treated quickly to try and maintain normal body temperature. Treating any seizures that occur post brain injury is crucial, since seizures could exacerbate secondary injuries. The use of seizure prophylaxis (drugs that prevent seizures) is more controversial but may be suggested for certain patients at high risk.
If signs of raised pressure in the skull or herniation (shift of brain tissue), early consultation with neurosurgery is advised. They’ll guide towards possible surgical interventions and monitoring methods to keep a check on pressure inside the skull. If the pressure inside the skull increases alarmingly, medications like mannitol or hypertonic saline can be administered. Though mannitol isn’t recommended if the patient is bleeding or has low blood pressure, it can help temporarily lower life-threatening elevations in skull pressure. Hypertonic saline is an alternative treatment that can be particularly useful in patients who don’t have adequate fluid levels or have systemic low blood pressure.
What else can Closed Head Trauma be?
It’s essential to understand the circumstances or event that potentially caused the injury. Heart rhythm problems, reduced blood supply to the heart, strokes, seizures, imbalances of minerals in the blood (especially low blood sugar), and swallowing harmful substances can lead to falls resulting in a head injury. These conditions could also create symptoms similar to a head injury, like changes in consciousness or alertness. It’s also crucial to be aware that facial injuries, including around the eyes, jaw, and skull, could occur at the same time as the head injury.
What to expect with Closed Head Trauma
In a 2008 study on traumatic brain injury (TBI) with 10,000 patients, 1 in 5 patients passed away within 2 weeks, 1 in 4 within 6 months, and 1 in 3 were either deceased or severely disabled at 6 months. Factors like old age, low post-resuscitation GCS score, low blood pressure, shortage of oxygen, abnormally dilated pupils, an increase in intracranial pressure, and existing diseases are indicators of likely poor outcomes.
In addition, certain brain imaging results can suggest a poor outcome. These results include changes in the 3rd ventricle or basal parts of the brain, shifting of the median structures of the brain, tiny hemorrhages, bleeding beneath the arachnoid membrane, and injuries to the brainstem.
There are two main tools doctors use to predict TBI outcomes: the CRASH and IMPACT Head Injury Prognosis Calculators. The IMPACT calculator predicts a 6-month outcome for adults with moderate to severe TBI, and the CRASH calculator predicts the rate of death at 14 days, and death or severe disability at 6 months in adults with a GCS of 14 or less. Please note, these predictions are general and might not apply to all individual cases, as they are based on broad population studies.
When it comes to mild TBI, often known as “concussion,” both adults and children under the age of 8 usually recover quickly, with 85% to 90% getting better within 14 days. Teenage boys generally recover in about 4 weeks, whereas teenage girls can take slightly longer. Interestingly, newer findings have shown that introducing light exercise early in the recovery process can speed up recovery.
Possible Complications When Diagnosed with Closed Head Trauma
Traumatic brain injuries, or TBIs, can have a range of effects. Some people may experience a good recovery and are able to return to their normal lives with only minor problems. Others may have a moderate disability, meaning they can still work, but perhaps not as much or in the same way as before. There are also cases of severe disability, where the person needs help from others with daily activities and can’t work. In the worst cases, a person may end up in a persistent vegetative state or even die.
If the TBI is mild, possible outcomes include:
- Post-concussive syndrome, which occurs in about 80% of patients
- Second impact syndrome, a rare but serious condition that causes rapid swelling in the brain and has a high death rate
- Post-traumatic epilepsy
- Chronic traumatic encephalopathy, a condition whose risk goes up with the number and frequency of concussions
Preventing Closed Head Trauma
The most effective way to decrease illness and death related to head injuries is through prevention. Ways to prevent these injuries include wearing seatbelts, using child safety seats or boosters, absolutely avoiding driving while under the influence of drugs or alcohol, wearing helmets when using vehicles without any safety features, wearing helmets for sports, taking measures to prevent falls in older people and others who are at risk, and securing windows to keep children from falling out.
For patients who experience mild traumatic brain injuries, educational resources that discuss how to return to normal activities and work or school have been proven to help reduce symptoms. You can find numerous materials available on the internet that can provide such information.
