When the head undergoes a blunt force trauma, the brain requires a certain amount of time to heal fully. Head and brain injuries can be complex and have physical, mental, and emotional health repercussions. Depending on the severity of a head injury, a patient will need to wait a length of time before resuming normal activities. If a patient suffers a concussion and then receives another blow to the head before the first injury heals, it can lead to a rare but potentially fatal condition known as second impact syndrome (SIS).
A Concussion’s Effects on the Brain
Post-concussion syndrome symptoms can vary greatly, but they may cause headache, dizziness, confusion, and disorientation, loss of balance, memory loss, and cognitive difficulties. If an athlete receives a blow to the head, he or she may not regain normal physical and mental function for hours, days, or weeks after the incident. However, many athletes jump straight back into the game without allowing a concussion to heal properly.
When someone undergoes two events involving head trauma close together, it can lead to second impact syndrome. SIS typically affects athletes in contact sports who return to the game too soon after a head injury. SIS is rare enough that many question its existence, believing SIS to be diffuse cerebral swelling resulting from a traumatic brain injury instead. Although this syndrome is rare, it can lead to healthy young patients dying within a few minutes of receiving the second blow to the head.
A second blunt force trauma to the head can cause massive brain swelling. When the brain swells, there is no place for it to go inside the skull. It therefore presses against the walls of the skull and begins to compress. Compression of the brain can cause a wide range of symptoms, from difficulty breathing to paralysis and coma. In severe cases, the brain can squeeze through small holes in the skull in an injury known as herniation. Herniation can decrease the brain’s blood flow and result in death.
The second blow to the head doesn’t have to be severe to cause SIS. Even a blow to the chest that jerks the person’s head can send forces to the brain. Athletes may stay alert for 15 seconds to one minute after the second impact but appear dazed or stunned. Within a short time, however, the athlete may collapse, be semi-conscious, and experience these symptoms:
- Dilated pupils
- Loss of eye movement
- Difficulty breathing
- Halted breathing
If a patient survives SIS, he or she will likely suffer severe neurological damage. SIS can put a patient in a coma for weeks or months. SIS survivors may need breathing tubes to survive and may need to receive their nourishment through feeding tubes intravenously.
How to Avoid Second Impact Syndrome
The populations most at risk of developing SIS are athletes who play sports that run the risk of blunt force traumas to the head. This can include football, boxing, baseball, hockey, and skiing. Once an athlete suffers a concussion, he or she should refrain from continuing the sport until the symptoms of the injury are completely gone. If in doubt about an athlete’s full recovery from a concussion, the athlete should avoid situations that could result in another blow to the head.
Athletes in particular, but anyone who has suffered a concussion or blow to the head, should speak up about their symptoms. Athletes should not fear retaliation for complaining about a head injury to coaches, as their lives could be at stake if they return to the game sooner than is healthy. SIS is a condition physicians are still studying, and until they know more about it, athletes who suffer concussions should be on guard.