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What is sepsis?

Sepsis is a serious medical condition that can result in organ damage or death. It happens when the body’s immune system has a severe response to an infection. Sepsis is a medical emergency. It needs to be treated right away.

Bacteria, viruses, and fungi can invade your body and cause disease. When your body senses one of these, the immune system responds. Your body releases certain chemicals into the blood that can help fight infection.

In some cases, the body has an abnormal and severe response to infection. This can cause inflammation around the body and damage your body’s cells. Blood clots may start to form all over the body. Some blood vessels may start to leak. Blood flow and blood pressure may start to drop. This harms the body’s organs by stopping oxygen and nutrients from reaching them. If this process isn’t stopped, organs in the body can stop working. This can lead to death.

Sepsis can be called different things according to how severe it is. Systemic inflammatory response syndrome (SIRS) is the mildest form. Sepsis, severe sepsis, and septic shock are more severe forms.

Sepsis is a common cause of death in hospital intensive care units. It can affect people of all ages, but children and older adults are at highest risk.

What causes sepsis?

Sepsis never happens on its own. It always starts with an infection somewhere in your body, such as:

  • Lung infection
  • Urinary tract infection
  • Skin infection
  • Abdominal infection (like from appendicitis)

Bacteria often cause these infections. Viruses, parasites, and fungi can also cause them and lead to sepsis. In some cases, the bacteria enter the body through a medical device such as a blood vessel catheter. An infection that spreads around the body through the bloodstream is more likely to cause sepsis. An infection in just one part of the body is less likely to lead to sepsis.

Sepsis is sometimes called blood poisoning, but this is misleading. Sepsis isn’t caused by poison.

Who is at risk for sepsis?

Some health problems that impair your ability to fight infection can raise your risk for sepsis, such as:

  • AIDS
  • Diabetes
  • Cancer
  • Liver disease
  • Severe burns
  • Conditions that affect the immune system
Careful treatment of these health conditions may help reduce the risk of sepsis.

What are the symptoms of sepsis?

Symptoms and signs of sepsis can include:

  • Fever or abnormally low temperature
  • Chills
  • Rash
  • Confusion
  • Trouble breathing
  • Swelling
  • Rapid heart rate and breathing rate
  • Low blood pressure
  • Signs of reduced blood flow to one or more organs
  • Less urine

The symptoms may vary depending on the severity of the sepsis. These symptoms may be mild at first and then quickly get worse.

How is sepsis diagnosed?

To diagnose sepsis, a doctor will ask about your medical history and your symptoms. He or she will do a physical exam. Some of the symptoms of early sepsis are the same as other medical conditions. This can make sepsis hard to diagnose in its early stages. An exam of the heart, lungs, and abdomen are needed to help diagnose sepsis.

You may also have tests, such as:

  • Urine tests to look for signs of infection in your urine, and check kidney function
  • Blood tests to looks for signs of infection in your blood
  • Imaging tests such as a chest X-ray, computed tomography (CT) scan, or other tests to look for the site of infection

A doctor will often diagnose SIRS in a person with certain signs. These include an abnormal body temperature, rapid heart and breathing rate, and abnormal white count but no known source of infection. A doctor can make an official diagnosis of sepsis when these symptoms are present and there is a clear source of infection. These problems plus low blood pressure or low blood flow to one or more organs is severe sepsis. And septic shock is when severe sepsis continues even with very active treatment.

How is sepsis treated?

Treatment is often done in a hospital’s intensive care unit (ICU). This is because sepsis needs very active care. Vital signs such as heart rate will be constantly watched. Blood and urine tests will be done often. Your condition will be watched and your treatment adjusted as often as needed.

The source of the sepsis must be treated. To do this, your doctor will likely use medications. The first treatment may be an antibiotic that works on many types of bacteria. When the exact type of bacteria is known, a different medication may be given. Pockets of infection may need to be drained. These are called abscesses. In some cases, an infected part of the body may need to be removed with surgery.

A person with sepsis will also need other types of treatments to help support the body, such as:

  • Extra oxygen, to keep up normal oxygen levels
  • Intravenous fluids, to help bring blood pressure and blood flow to organs back to normal
  • A breathing tube and a ventilator, if the person has trouble breathing
  • Dialysis, in case of kidney failure
  • Medications to raise the blood pressure
  • Other treatments to prevent problems such as deep vein thrombosis and pressure ulcers

Most people with mild sepsis do recover. But even with intense treatment, some people die from sepsis. Up to half of all people with severe sepsis will die from it.

What are the possible complications of sepsis?

Many people survive sepsis without any lasting problems. Other people may have serious problems from sepsis, such as organ damage. Some of possible complications of sepsis include:

  • Kidney failure
  • Tissue death (gangrene) of fingers or toes that may require amputation
  • Permanent lung damage from acute respiratory distress syndrome
  • Permanent brain damage, which can cause memory problems or more severe symptoms
  • Later impairment of your immune system, which can increase the risk of future infections
  • Damage to the heart valves (endocarditis) which can lead to heart failure

When should I call the doctor?

Call or see a doctor right away if you or someone else has symptoms of sepsis. Early diagnosis and treatment can help improve the chances of a good recovery.

Key points

Sepsis is a serious medical condition that can result in organ damage or death. It happens when the body’s immune system has a severe response to an infection.

  • Sepsis is a medical emergency. It needs to be treated right away.
  • Possible signs and symptoms of sepsis include fever, confusion, trouble breathing, rapid heart rate, and very low blood pressure.
  • The infection that caused sepsis will be treated first. Health care providers will also treat the symptoms of sepsis with medications, fluids, and breathing support.
  • Sepsis can cause serious complications. These include kidney failure, gangrene, and death.

Next steps

Tips to help you get the most from a visit to your health care provider:

  • Before your visit, write down questions you want answered.
  • Bring someone with you to help you ask questions and remember what your provider tells you.
  • At the visit, write down the names of new medicines, treatments, or tests, and any new instructions your provider gives you.
  • If you have a follow-up appointment, write down the date, time, and purpose for that visit.
  • Know how you can contact your provider if you have questions.

Medical Reviewers:

  • Larson, Kim, APRN, FNP
  • Motive Medical Intelligence subject matter expert