Sepsis hour-1 bundle: updated Surviving Sepsis Campaign 2021 practice

Also known as Hour-1 bundle · Sepsis bundle · Surviving Sepsis Campaign · SSC 2021 · Sepsis six · Sepsis resuscitation

SSC 2021 (Evans): measure lactate and guide resuscitation to decrease it; cultures before antimicrobials if no substantial delay (under 45 min); antimicrobials immediately, ideally within 1 hour of recognition for possible septic shock; at least 30 mL/kg IV crystalloid within the first 3 hours for hypoperfusion or shock (weak); noradrenaline first-line, initial MAP 65 mmHg. Kumar 2006: 7.6% average survival decrease per hour of antimicrobial delay after hypotension over the ensuing 6 hours. Seymour 2017 (n=49,331): 3-hour bundle completion and antibiotic time each OR 1.04 per hour for in-hospital death. PRISM: EGDT 90-day mortality 24.9 vs 25.4%, not better than usual care.

high18 referencesUpdated 3 Sept 202613 min readSource-verified · Sept 2026

Checked against its sources on 3 Sept 2026

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8 MCQs

The one-line answer

SSC 2021 still cites the Hour-1 sepsis bundle, but the timed recommendations are not all a 60-minute checkbox: measure lactate and guide resuscitation to decrease an elevated value; obtain blood cultures before antimicrobials if that causes no substantial delay (the 2016 statement kept in 2021: under 45 minutes); give antimicrobials immediately, ideally within 1 hour of recognition in possible septic shock; give at least 30 mL/kg IV crystalloid within the first 3 hours for sepsis-induced hypoperfusion or septic shock (weak); start noradrenaline first-line to an initial MAP of 65 mmHg, peripherally if central access would delay therapy. Seymour 2017 (New York, n=49,331) found each additional hour to a 3-hour bundle (cultures, antibiotics, lactate) and each hour to antibiotics associated with in-hospital death at OR 1.04 per hour — not a 4-percentage-point absolute mortality rise, and not a faster fluid bolus.^[7]^[11]

Meet the patient

A 65-year-old man presents to ED with confusion, fever 38.8 degrees, RR 28, BP 82/50, lactate 4.5 mmol/L, with clinical signs of a urinary source. The clock starts the moment you recognise sepsis — in possible septic shock, SSC 2021 asks for antimicrobials immediately, ideally within 1 hour of recognition, with the other elements — lactate, cultures, fluids, vasopressors — started alongside.^[7]

Sepsis is common, and its burden outlasts the acute episode — survivors are left with new cognitive impairment and functional disability. The intensivist's job distils to five questions asked in the first hour and re-asked every hour thereafter: is this sepsis? What is the bug and where is the source? Is the circulation perfusing the organs? Is the resuscitation adequate? What can I physically remove or drain to stop the infection? The hour-1 bundle operationalises these.^[13]

References18Show

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