Sepsis

Risk: People most at risk for sepsis are those whose immune systems are weakened. They include people with diseases such as HIV/AIDS, multiple sclerosis, diabetes, and lymphoma, as well as transplant patients taking immunosuppressant drugs and people receiving chemotherapy. Other people at risk are those who have had recent surgery, who have invasive devices such as bladder catheters or intravenous lines, or who have been burned over a large part of their body. Those over age 85 who have other serious medical conditions are at particularly high-risk of dying from septic shock. Risk is independent of sex or race.

Incidence and Prevalence: The incidence of sepsis has been increasing for the past 30 years because of the increased use of intravascular catheters and other invasive devices; widespread use of immunosuppressive medications; the AIDS epidemic; the fact that individuals with cancer and diabetes are living longer (increasing the possibility of infection); and the emergence of antibiotic-resistant organisms.

Septic shock is the most common cause of death in intensive care units, and the thirteenth most common cause of death in the US. Incidence increases with age. One large study estimated that in the US, there are more than 750,000 cases of sepsis annually (Cohen 614).

History: The individual will usually complain of fever (febrile) and chills. The individual may complain of shortness of breath and have a feeling of apprehension or confusion. There may be specific symptoms suggesting the site of infection (such as abdominal pain if there is gangrene of the intestine), but such localized symptoms are frequently absent. There may be a history of recent surgery; lung infections such as pneumonia or other severe known infections; or recent puncture wounds, deep cuts, or burns. The individual might have an invasive tube such as an indwelling bladder catheter or an intravenous line, increasing the risk of sepsis.

Physical exam: On physical exam, the individual will usually have a fever, though some individuals may be hypothermic. Examination might suggest the source of the infection. If septic shock develops, blood pressure drops and heart rate rises (tachycardia). There will be abnormal breathing sounds, indicating fluid accumulation in the lungs. Several other common symptoms include rapid, shallow breathing; flushed skin and sweating; weak pulse; dehydration and decreased urine output; sudden high fever with chills; cold hands and feet with a bluish tinge to the skin (cyanosis); rapid heartbeat; prostration (extreme exhaustion); and changes in mental state, especially among the elderly, reflected as confusion, agitation, disorientation, or coma. Some individuals develop a red, pinpoint rash (petechiae) caused by capillary hemorrhages beneath the skin.

Tests: Normally tests begin with a complete blood count (CBC). A blood count may show nonspecific signs of infection. Blood samples or samples of sputum (mucus), spinal fluid, and urine may be taken for culture to identify the infecting organism. Other blood tests will monitor electrolytes as an indication of renal functioning. A blood gas analysis may show a low oxygen content in the blood (hypoxemia). A chest x-ray may be done to look for evidence of pneumonia, and a CT scan may be done if infection in the abdomen is suspected. Monitoring is an ongoing process as sepsis is treated, and these tests will be repeated as the individual's condition changes.