Second Impact Syndrome

  • This is a condition where the brain swells rapidly after a second impact before the first brain injury/concussion heals.
  • 50% of athletes will die from SIS
  • 100% will become disabled from SIS
  • It is so important to hold the athlete out until their concussion is healed.

ESPN Video exploring Preston Plevretes’ life after tragedy w/ Second Impact Syndrome

What is Second Impact Syndrome (SIS)

What is Second Impact Syndrome (SIS)? Second impact syndrome (SIS) occurs when an athlete returns to sport too early after suff­ering from an initial concussion the athlete may receive only a minor blow to the head or a hit to the chest or back that snaps the head enough to have the brain rebound inside the skull.

An athlete who is recovering from a concussion, but who has not yet fully recovered, is at risk for second impact syndrome (SIS). Typically, the athlete suff­ers post-concussion signs and symptoms after the first head injury, such as headache, visual, motor or sensory changes or mental difficulty, especially with the thought and memory process. Before these symptoms have cleared, which may take minutes, hours, days or weeks, the athlete returns to competition and receives a second blow to the head.

Because the brain is more vulnerable and susceptible to injury after an initial brain injury, it only takes a minimal force to cause irreversible damage. The brain’s ability to self-regulate the amount of blood volume to the brain is damaged resulting in increased cerebral blood volume which can result in brainstem herniation and death.

The pressure to the brain increases rapidly causing brain death in as little as three to five minutes. Because brain death is so rapid, second impact syndrome has a high fatality rate in young athletes.

Most cases of SIS have occurred in young people, who are thought to be particularly vulnerable. In order to prevent SIS, NeuroSport® Concussion Management guidelines have been established to prohibit athletes from returning to a game prematurely. For example, professionals recommend that athletes not return to play before symptoms of an initial head injury have resolved. Due to the very small number of recorded cases of SIS, there is doubt about whether it is a valid diagnosis. However, the syndrome is recognized by physicians.

Once an athlete has suff­ered an initial concussion, his or her chances of a second one are 3 to 6 times greater than an athlete who has never sustained a concussion. A 2013 study by researchers at Boston Children’s Hospital found that concussion symptoms lasted twice as long for patients with a history of previous concussion as those without such a history (24 versus 12 days).

HPN Concussion Information Scans

Second-impact syndrome (SIS) is rare but can be fatal. The condition can result after a second concussion occurs during the period when the brain is still healing from a previous concussion.

SIS results in dangerous brain swelling and bleeding that can cause death or permanent brain damage. It can even occur weeks after a concussion diagnosis, according to an article by the University of Washington Medicine.

Second Impact Syndrome Symptoms

SIS Symptoms

SIS symptoms are similar to concussions, but may also include:

  • Failure of the lungs to contract and breath normally
  • Unequal size of the eye’s pupils
  • Coma
  • Personality changes

In terms of concussions in sports, SIS is preventable by removing concussed players from all practice and play until concussion symptoms are gone and the individual is checked by a physician. The dangers of football concussions, particularly high school concussions, have been specifically highlighted in the media recently because of the increased danger of SIS and permanent brain damage in adolescent athletes. A 2013 survey found that nearly all high school football players know the risks of returning to play with concussion symptoms, but more than half said they would “always or sometimes continue to play with a headache sustained from an injury.”

About than 26 percent of former National Football League (NFL) players had suffered three or more concussions during their careers, according to a 2000 survey. It is unknown just how many of the injured players involved in the NFL concussion lawsuits were put at risk by continuing to play with symptoms of a concussion, but the NFL litigation will further highlight the necessity of protecting players from the dangers of concussions and SIS.

If you or someone in your care has suffered from second impact syndrome due to the failure of others to follow proper guidelines for concussions, it’s important to act. Athletes of all ages are suffering potentially lifelong impairment from SIS, and it’s completely avoidable.

Send a message to those in charge that the health and well-being of athletes is their most important obligation of all.

Second Impact Syndrome Story

Zachary Lystedt suffered a head injury in an 8th grade football game, but returned to the field and continued playing. The star athlete played the entire game before collapsing on the field. He was diagnosed with second impact syndrome (SIS). He is now disabled, and his family has devoted their time to preventing other young athletes from suffering the same fate.

Because of the efforts of the Lystedt family, there is now legislation in the state of Washington to protect young athletes who have suffered a concussion from reentering a game without a medical release. Similar legislation is being written across the country following the model of the law named after Zachary Lystedt.

His story and others just like it have been the driving force behind the current push across this country to makes sports safer for young athletes. Change starts with education and awareness.

Zachary’s Story
QEEG HPN Neurologic 10 Step Program

How Is Second Impact Syndrome Diagnosed?

HPN Concussion Management’s Approach to Brain Recovery and the Treatment of Concussion, HPN Concussion Management Quantitative qEEG Measurements and the 10 Steps to HPN Treatment of Post-Concussion Syndrome.

Start 10 Step Treatment

For More Information on the HPN 10 Step Treatment of Post-Concussion Syndrome Contact Fred Willis of HPN Neurologic.

For that you will wear a cap with sensors and electrical readings from your scalp will be taken. It is the same as getting an EKG where electrical readings are taken from your heart. This will take about 20-30 minutes. QEEG (quantitative electroencephalogram) also known as a “brain mapping” uses digital technology, of electrical patterns at the surface of the scalp which primarily reflect cortical electrical activity or “brainwaves. QEEG (quantitative electroencephalogram) is also known as a “brain mapping”.

If a brain injury is suspected, an immediate computed tomography (CT) of the head should also be ordered. A CT scan is more sensitive than an MRI to detect acute intracranial bleeding. A thorough medical history specifically regarding mechanism of injury and history of head injury should be obtained from the patient if the patient is conscious or from an eyewitness if the athlete is rendered unconscious.

Signs of Second Impact Syndrome

Signs and Symptoms of Second Impact Syndrome

Initially, the athlete may not lose consciousness, but may look stunned. The athlete may also be able to make it to the sideline where the athlete may suddenly collapse within minutes.

The condition worsens rapidly will loss of consciousness, loss of eye movement, dilated pupils, coma, and then respiratory failure. This can all take place within minutes on the sideline.

Because this is a life-threatening emergency, life-saving measures must be taken within minutes for there to be any hope for the athlete. Treatment should be undertaken to maintain an airway, and to provide rescue breathing and CPR if necessary.

Who Gets Second Impact Syndrome?

Any athlete may be at risk for SIS if he/she returns to sports competition while still experiencing the symptoms from an initial injury. According to a study published in the Journal of Athletic Training (2007) and published on Neurotrauma Research Laboratory website, between 1.6 and 3.8 million sport-related concussions occur every year.

The collegiate sports with a higher incidence of concussion include in descending order using injury rate per 1000 athletes exposed (IR/AE):

Mens Football Concussions

Football (M) 2.34

Ice Hockey Concussion

Hockey (M) 1.47

Womens Soccer Concussion

Soccer (F) 1.42

Wrestling Concussion

Wrestling 1.27

Mens Soccer Concussion

Soccer (M) 1.08

Women's Lacrosse Concussion

Lacrosse (F) 0.70

Field Hockey Concussion

Field Hockey 0.57

Womens Basketball Concussions

Basketball (F) 0.50

Mens Basketball Concussions

Basketball (M) 0.32

Softball Concussion

Softball 0.25

Baseball Concussions

Baseball 0.19

Volleyball Concussion

Volleyball 0.15

It is logical to conclude that sports in which concussions are more prevalent will also be sports in which athletes will be more at risk for SIS.

Second Impact Syndrome Prevention

What Can I Do to Prevent Second Impact Syndrome?

Because SIS has a higher mortality rate in young athletes, the focus needs to be on the prevention of SIS. The key to preventing SIS is to ensure that athletes do not return to sport with any post-concussion symptoms. To this end, legislation is working its way through the country (at both the national and state levels) to mandate that athletes do not return to sport on the same day that they are concussed and that they do not return to sport unless they have been cleared by a sports medicine professional.

Education regarding the proper diagnosis and management of a concussion (especially in light of recent research) needs to occur throughout sports communities at all levels of involvement including the athletes, parents, coaches, athletic administrators, physicians, and sports medicine personnel. As awareness increases as to the dangers of SIS and the importance of proper management for an athlete with a concussion, the incidence of SIS should begin to decrease.

Schools, colleges, and universities that do not heed the warnings and do not properly treat concussions may end up paying the price along with the injured athlete.

Second Impact Syndrome Prognosis

What Is the Prognosis for an Athlete with Second Impact Syndrome?

As stated above, second impact syndrome has a high mortality rate in young athletes. Patients that survive may suffer from permanent neurological symptoms including impacting the following systems:

  • Speech
  • Cognitive ability
  • Sensory ability
  • Vision
  • Perception
  • Hearing
  • Smell
  • Taste
  • Social/emotional interactions


Concussion Management

Tel: (978) 594-8665