Sepsis

Overview

•Sepsis = dysregulated host response to infection causing organ dysfunction - not simply 'severe infection'

•qSOFA (bedside screening, score ≥2 triggers urgent assessment): altered mentation + RR ≥22 + SBP ≤100 mmHg

•Septic shock = sepsis + vasopressor-dependent hypotension + lactate >2 mmol/L despite resuscitation

💡

A temperature persistently elevated despite antipyretics suggests bacterial rather than viral infection - do not be falsely reassured by a 'minor' source.

Presentation

•Tachycardia (HR >90/min in adults) - early and sensitive

•Hypotension (SBP <100 mmHg) - late and serious

•Tachypnoea (RR >22/min) - driven by lactic acidosis and/or pulmonary pathology

•Pyrexia (>38°C) or hypothermia (<36°C)

•Altered consciousness - cerebral hypoperfusion; oliguria - early marker of renal hypoperfusion

🚨

A non-blanching petechial or purpuric rash in a septic patient = assume meningococcal disease until proven otherwise. Give benzylpenicillin IV/IM immediately - do not wait for investigations.

Investigations

•Blood cultures (x2 sets) - before antibiotics if possible; never delay antibiotics >1 hour waiting for cultures

•Lactate (blood gas) - >2 mmol/L = hypoperfusion ('cryptic shock'); >4 mmol/L = high mortality, mandates ICU review

•FBC - leucocytosis (>12 x10⁹/L) or leucopenia (<4 x10⁹/L); thrombocytopenia suggests DIC

•U&Es/creatinine - AKI common; guides fluid management

•Urine dipstick and MC&S - UTI is one of the commonest sources

•Chest X-ray - assess for pneumonia; may reveal ARDS in severe cases

•Clotting screen - prolonged PT/APTT and low fibrinogen suggest DIC

Management - Sepsis Six

Complete all six actions within one hour of recognition. Divided into three 'gives' and three 'takes'.

🎯

Time to antibiotics is the single most important modifiable determinant of mortality - every hour of delay increases mortality. Draw cultures first, then give antibiotics; if there is any conflict, treat immediately.

•Escalate to ICU if septic shock criteria met (vasopressor-dependent hypotension or lactate >4 mmol/L despite resuscitation)

⚠️

Aspirin must NOT be given to children - risk of Reye's syndrome. Use paracetamol or ibuprofen only.

Paediatric Considerations

•In children >12 years, HR >100 bpm is abnormal - use age-adjusted thresholds when assessing for sepsis

•A child with raised temperature, tachycardia, SBP <100 mmHg, and raised RR meets both SIRS and qSOFA criteria - initiate Sepsis Six immediately

•If bacterial throat infection is the suspected source, phenoxymethylpenicillin is the targeted antibiotic - but in the context of sepsis, use IV broad-spectrum antibiotics first