Bacterial Infection

Bacterial infection in the ICU, commonly called sepsis, can cause many complications. It's a leading cause of death in ICU patients.

Besides bacteria, viruses and even  fungus can lead to severe infection.

In general, these organisms all affect the body in the same ways and lead to organ damage.

Initially sepsis starts as an inflammation. A biochemical reaction begins.

The body responds with fever, discomfort and an elevated white blood cell count.

If unchecked, the infection continues, and other organs begin to be involved.

Organs Affected or Damaged by Bacterial Infection

Any organ in the body can be affected. 

Pneumonia is very common bacterial infection, especially in older patients and those bedridden.

Urinary tract infections can easily develop, especially if a patient has a catheter in place to drain urine.

After surgery, the wound can develop a bacterial infection, even if antibiotics were given.

Catheters or tubes in place to give blood or fluids can lead to a blood stream infection.

Meningitis is a bacterial infection of the brain.

An abdominal infection can happen if the intestines become blocked.  Pressure can build up and cause a rupture of the contents into the abdomen.

Occasionally, after elective abdominal or chest surgery a serious infection can develop.

What Happens when When Bacterial Infection Occurs?

Many different biochemical reactions to take place. Some can be very harmful to the patient.

Many times a bacterial infection causes patients to become confused, disoriented and sleepy.

Most will have a fever; some may have a lower than normal temperature.

The heart rate will often be elevated.

The white blood count becomes very high. In a few cases it might be too low.

X rays and scans can show a pneumonia or a collection of pus causing the infection.

Surgical wounds may have draining puss.

The appetite will be poor.

Sepsis can worsen and become septic shock. This is a serious, life threatening condition.

The diagram below shows the various stages of sepsis. They begin to overlap, and if untreated, severe sepsis and septic shock develop.

Septic Shock

When bacteria invade the body, they cause a very complicated chemical reaction. This reaction is designed to combat the infection.

At times, the body can over respond and the reaction doesn't shut down. This leads to the septic shock state.

Patients in septic shock will have low blood pressures and usually a very high heart rate.

Medications and a large amount of intravenous fluids will be necessary to improve blood pressure.

The fluids may cause considerable swelling, which is usually temporary.

Most times, patients in septic shock are not very responsive and can become very agitated.

Besides a fever, they may have chills and something called rigors. The body becomes very rigid with continuous trembling.

The lungs may become congested, making breathing difficult and not providing enough oxygen.

The stomach or abdomen may swell if the infection is located there.

Treatment for Septic Shock

If septic shock develops, a patient not already in the ICU will be rapidly moved there.

The doctors and nurses will immediately work to get the blood pressure back up.

Large catheters are inserted so that fluids and blood can be rapidly given.

Several different kinds of medications can be used to improve the blood pressure. These are given continuously and adjusted by the bedside nurse.

Cultures will be taken from blood, urine, lungs and any other suspicious places.

Antibiotics are immediately started. Until the actual cause is known, the antibiotics used will be those that can treat any possible infection.

X rays and scans are done to locate the infection. Some  can be done  at the bedside. Others require a trip to the radiology department.

Fluid collections found and thought to be a possible source of infection will be drained. Some may require an actual operation.

Besides cultures, many blood tests are done and used to plan therapy. These will be repeatedly done to judge the patient's progress.


Many of the  organs can be damaged by sepsis and septic shock.

The heart may not pump the required amount of blood. This causes low blood pressure. Organs fail due  to not having enough blood flow.

The lack of blood flow can cause the heart to have irregular heart beats. This also reduces blood flow and can be fatal if not corrected.

Sepsis causes congested lungs. This usually means a ventilator will be needed to help with breathing and provide enough oxygen.

The lung congestion often leads to pneumonia and more time on the ventilator.

The kidneys can fail in septic shock; particularly in the elderly. Dialysis or the artificial kidney may be necessary for several weeks.

A catheter is temporarily placed in a vein. This permits removal of impurities in the blood and returning the blood to the patient.

Brain function deteriorates in septic shock. Patients can become confused, non responsive and agitated, They rarely remember their ICU stay.

Failure of the liver sometimes happens. However as the infection is controlled, the liver usually improves on its own.

The intestinal tract usually functions poorly during septic shock.

Nutrition,using specialized formulae are given through a tube threaded into the intestinal tract. 

Recovery from Septic Shock

About 70% of patients now survive septic shock

Death usually results from organs going into failure.

Patients younger than 60 years will usually have higher survival rates.

The elderly and those with chronic medical issues such as diabetes or poor kidney function will tend to have lower survival rates.

An uncomplicated case will most time be able to leave the ICU in 7-10 days.

A longer ICU stay more complications increases the need for a rehabilitation unit following hospital discharge.

Questions to Ask

  • Which organs have been affected by the infection?
  • Will they require any special treatment?
  • Will these organs have any permanent damage?
  • How do we know our loved one is responding to the treatment?
  • What happens if he or she does not respond to the treatments?
  • Our loved one is not responsive, is that a bad sign?
  • Our loved one has become very swollen. What does that mean?
  • If dialysis(artificial kidney) is needed, will it be permanent?
  • How do we know the right antibiotics are being given.
  • We don't think are loved one would want all this done. what should we do?
  • Why can't we stay in the room all the time?