What Is Second Impact Syndrome? | Traumatic Brain Injuries

woman with a bandage over her head with
Madeleine Jones
March 2, 2022

A traumatic brain injury – like a concussion – can have devastating consequences on the victim, and is often life-changing. According to the CDC, there were around 61,000 traumatic brain injury-related deaths in the US in 2019. Second Impact Syndrome happens when a traumatic brain injury victim suffers a second injury before fully healing from the first one. 

A second impact can cause damaged brain tissue to swell up inside the skull – also known as cerebral edema – and can cause severe brain damage or death.

Causes of Second Impact Syndrome

A concussion injury that leads to SIS brain injury can happen as a result of a work accident, sports injury, car accident, and many other unfortunate situations. Cogburn Law protects the rights of victims of second impact syndrome in Nevada – We will fight for you to secure a fair settlement that compensates you for your financial losses, pain, and suffering.

Second Impact Syndrome Symptoms

A concussion often causes minor injuries, and most victims recover in a matter of hours. However, there are more severe symptoms of SIS, including:

  • Blindness
  • Respiratory failure
  • Brain herniation
  • Loss of consciousness
  • Pupils severely dilated
  • Seizures
  • Death

If you receive a second hit to the head before recovering from an existing concussion, you can suffer considerable damage. Some victims never get to recover from their injuries and sometimes experience long-term difficulties with movement, learning, or speech. Neurosurgery is often required, and the most severe cases often result in death.

SIS in Sports

SIS is very common among athletes that play baseball, skiing, boxing, hockey, or football. This is because they are prone to hitting their head in these sports, and therefore an athlete may not really pay much attention to the chances of getting a concussion.

This is especially true if a sports league or coach doesn’t emphasize safety policies that need medical evaluations every time a player hits their head.

Additionally, a sports league or coach should never push a player to return to the field until their health has been cleared by a doctor. Going back to sports too early may put the victim at severe risk of SIS, and therefore more severe effects of their TBI. If someone acts negligently and causes SIS in an athlete or someone else, they should be held liable for their negligence.

Second Impact Chain Reaction

A second impact causes a chain reaction in the brain. As a rule, the brain and other organs keep a steady blood flow by narrowing and widening blood vessels with pressure changes. A second blow to the head, even a minor one, can shut down this blood flow, leading to brain swelling.

The swelling in the brain can cause pressure to increase inside the skull and force tissues to move from their original position in the brain. A second impact can quickly kill someone – as soon as in two minutes. Brain pressure and swelling can push on the brain stem, which is where the regulatory systems of the body are. Whenever a brain stem fails, breathing fully stops and the body dies.

Minutes or even seconds after a second impact, a victim may appear stunned. They may fall or collapsed to the ground and have a seizure. The pupils may rapidly change in size, eye movement can be lost, and respiratory failure can all be signs of SIS. Given that victims tend to die within minutes, there is really no way of treating second impact syndrome. The only way to avoid SIS is through prevention.


SIS can be prevented by keeping brain injury victims from returning to strenuous activities. This syndrome can be rare in the overall population, and more common in male athletes. For this reason, whenever a person suffers an initial blow to the head, even if it’s a mild one, a victim should be watched closely for signs of injury.

SIS and Personal Injury

As in any other personal injury claim, at Cogburn Law, we will review the situation that caused your injury. Did you have the proper or necessary helmet to protect you from head injury? Was your child’s chosen sport emphasized on their safety? Did their coach return them to the field without having been clinically cleared?

Related Post: Paragard IUD Linked To Dangerous Brain Injury

Traumatic Brain Injury Attorney In Las Vegas

Was your traumatic brain injury caused by a car accident, or by someone else’s negligence? Cogburn Law is ready to help you. We will work with you and build a strong case to get you the compensation you deserve. Give us a call at (702) 747-6000 today and we will schedule an initial free consultation.