Condition · Blood, infection & other

Sepsis

Also known as: septicaemia, blood poisoning, septic shock

Life-threatening organ dysfunction caused by a dysregulated body response to infection.

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Overview

Any infection can trigger sepsis, most often pneumonia, urinary infection, abdominal infection or skin infection. The immune response spills over into the whole body: blood vessels leak and dilate, clotting is disturbed, and organs fail. Sepsis kills millions a year; each hour of delay in antibiotics raises mortality, so recognition is everything.

Causes

  • Bacterial infection most often (pneumococcus, E. coli, staphylococci, streptococci, meningococcus)
  • Viral, fungal or parasitic infections

Risk factors

  • Age under 1 or over 75
  • Weak immune system: chemotherapy, steroids, diabetes, no spleen
  • Recent surgery, wounds or catheters
  • Pregnancy and the weeks after birth
  • Chronic lung, liver, kidney disease

Symptoms

What a clinician may find

  • Fast breathing (over 22/min), fast pulse, low blood pressure
  • New confusion or drowsiness
  • Mottled, cold or clammy skin; non-blanching rash
  • Passing little urine
  • Very high or abnormally low temperature

Complications

  • Septic shock and death
  • Acute kidney injury, lung failure, liver failure
  • Disseminated clotting and limb loss
  • Long-term physical and cognitive effects

Diagnosis

Clinical recognition (NEWS or qSOFA scores), blood cultures and cultures from the likely source before antibiotics, lactate, blood counts, kidney and liver function, clotting; imaging to find the source.

Treatment

The 'sepsis six' within an hour: oxygen, blood cultures, intravenous antibiotics, intravenous fluids, lactate measurement and urine output monitoring; then source control (drain an abscess, remove an infected line), vasopressors and organ support in intensive care.

Prevention

Vaccination, hand hygiene, prompt treatment of infections, careful care of wounds and catheters, and knowing the warning signs.

When to seek care

Call emergency services for an infection with slurred speech or confusion, extreme shivering or muscle pain, passing no urine in a day, severe breathlessness, mottled or discoloured skin, or a feeling of impending doom; for children also fast breathing, a fit, blue or pale skin, a non-fading rash, or unusual drowsiness.

Educational content. Educational overview of a condition, not personal medical advice. Diagnosis and treatment decisions belong to the person's own clinical team.