Sepsis: why the first hours decide the outcome

Sepsis is not an infection. It is what happens when the body's response to an infection begins to damage its own organs. That distinction matters, because it explains why a person can have an infection that seemed unremarkable on Monday and be in intensive care by Wednesday.

What is actually going wrong

When the immune system responds to an infection, it releases chemical signals that cause inflammation. In sepsis that response becomes generalised and dysregulated. Blood vessels dilate and leak, blood pressure falls, small clots form throughout the circulation, and tissues stop receiving enough oxygen. Organs begin to fail, often several at once.

Septic shock is the most severe form, where blood pressure cannot be maintained despite fluid resuscitation. Mortality rises sharply at that point.

Any infection can trigger it. The commonest sources are the lungs, the urinary tract, the abdomen, the skin and soft tissue, and infected intravenous lines. In Nigeria, severe malaria, typhoid with perforation, obstetric infection after delivery or unsafe abortion, and infected wounds are all frequent causes.

The signs that should not wait

Go to a hospital immediately if someone with a known or suspected infection develops any of the following.

• Confusion, disorientation or unusual drowsiness
• Breathing that is fast or laboured
• A fast heart rate with low blood pressure, or dizziness on standing
• Passing very little urine, or none for eight hours or more
• Skin that is mottled, unusually pale or cold and clammy at the hands and feet
• A rash that does not fade when pressed with a glass
• Shivering with severe muscle pain, or a temperature that is very high or unusually low
• A general sense from the patient or family that something is very badly wrong

That last point is not sentimentality. In studies of deterioration, family concern is a reasonably good predictor, and it is frequently the earliest signal available.

Note also that a low temperature is as concerning as a high one. The absence of fever does not exclude sepsis, particularly in the elderly, the very young, and people with weakened immunity.

What a hospital should do in the first hour

There is an internationally established bundle of actions for the first hour after sepsis is recognised, and delivering it reliably saves more lives than any single drug.

• Measure lactate. It indicates how badly the tissues are being deprived of oxygen and it tracks the response to treatment.
• Take blood cultures before antibiotics. Once antibiotics are given, the organism often cannot be grown, and identifying it is what allows treatment to be narrowed correctly later.
• Give broad spectrum antibiotics immediately. Not after the cultures come back. Every hour of delay in septic shock measurably increases mortality.
• Give intravenous fluid for low blood pressure or a raised lactate.
• Start vasopressors where blood pressure does not respond to fluid.
• Find and control the source.

Source control is not optional

Antibiotics cannot sterilise a collection of pus. If there is an abscess, an obstructed and infected urinary system, a perforated bowel, dead tissue or an infected line, that source has to be physically dealt with by drainage, removal or surgery.

Sepsis that fails to improve on appropriate antibiotics is very often sepsis with a source that has not been controlled. If a patient is not improving, that is the question to ask.

Why intensive care

Severe sepsis needs continuous monitoring and often organ support: ventilation where the lungs are failing, vasopressors to maintain blood pressure, dialysis where the kidneys have shut down, and correction of clotting abnormalities. None of that can be delivered on a general ward.

Recovery is slower than families expect

Survivors of severe sepsis frequently take months rather than weeks to feel themselves. Profound weakness from muscle loss, fatigue, poor concentration, disturbed sleep and low mood are all common, and none of them means something further has gone wrong.

Families are often told the patient is out of danger and are then alarmed by how unwell they remain at home. Knowing in advance that this is the normal shape of recovery makes it considerably easier to bear, and makes it clearer when something genuinely is wrong.

What reduces the risk

• Treat infections properly and complete prescribed antibiotic courses
• Do not self prescribe antibiotics, which drives the resistance that makes sepsis harder to treat
• Keep immunisations current, particularly pneumococcal and influenza in older adults and those with chronic disease
• Control diabetes, which markedly increases susceptibility
• Clean and monitor wounds, and seek review for any wound that becomes red, hot, swollen or increasingly painful
• Seek care early in pregnancy related infection, which progresses unusually fast