Skip to main content

What Is Stress?

Critical Incident Stress

"CIS occurs when an emergency worker becomes overwhelmed by what they experience at the scene. The ability to cope weakens and the worker suffers physical, cognitive and/or emotional problems."

The Trauma of a Critical Incident

The body reacts physically to a critical incident. Sweaty palms, nausea and increased pulse rate are the overt signs of the body's exposure to trauma. Yet the emotional reactions to the sight and sounds of broken bodies, blood and death are usually suppressed.

This conscious effort by the mind to block out the difficult reality of an incident is a natural, human response. Yet when the emotional stress is so internalized, each new incident has a cumulative effect and begins to take its toll. Until, like incredible fatigue, the emergency service worker can no longer respond.

Predetermined critical incidents include:


  • Serious injury of emergency personnel
  • Line of duty death
  • Mass casualty incidents
  • Death of a child or violence inflicted upon a child
  • Mass fatality incidents
  • Suicide of an emergency responder
  • Loss of a life of a patient following extraordinary and prolonged rescue
  • Terrorism
  • Incidents which attract unusual, prolonged or critical media coverage
  • Responder identifies person or event with own personal experience
  • Any other event that causes unusually strong reactions
Acute Stress

Acute stress reaction may happen while you are still involved with the situation.

Symptoms of Acute CIS may include:

  • Panic
  • Hyperventilation
  • Paresthesia (Numbness)
  • Chest Pain
  • Nausea
  • Vomiting
  • Elevated blood pressure and pulse
  • Inability to function
  • Headache
  • Anxiety
  • Palpitations
Delayed Stress

Delayed stress reaction – the stress responses occur hours, days, or weeks after the incident.

Symptoms of Delayed Stress may include:

  • Increased anxiety
  • Depression
  • Increased sensitivity to odors (i.e. blood, urine, burning flesh)
  • Inability to control emotions
  • Increased irritability
  • Decreased sexual desire
  • Frequent crying spells
  • Increased or decreased appetite
  • Weight loss or gain
  • Frequent headaches
  • Menstrual cycle changes
  • Flashbacks
  • Nightmares
  • Insomnia
  • Poor concentration
  • Severe fatigue
  • Feelings of vulnerability
  • Grief
  • Chronic diarrhea
  • Increased alcohol and drug consumption
  • Feelings of guilt
  • Obsessive thoughts of the incident
  • Marital conflict
  • Loss of sense of humor
  • Increased use of "dark" humor.

Remember that these are NORMAL reactions to abnormal stress. Remember that all debriefings are confidential and that they are NOT a time for criticism.