Skip to content
medschool

Educational content. Not a substitute for clinical judgement. Read full disclaimer.

Emergency Medicine
Emergency Medicine

Sepsis-Six in the First Hour

A walk-through of the UK Sepsis-Six bundle as it actually plays out in a busy resuscitation room, plus what tends to slip.

Published
12 May 2026
Read time
3 min read
Procedure GuideFoundation / Junior Doctor

The Sepsis-Six is a UK pragmatic translation of the early bundle from Surviving Sepsis — three "give" items and three "take" items. The goal is to start them all within the first hour of recognition.

Recognition first

Before the bundle: does this patient actually have sepsis? Use NEWS2 ≥5, or look for the combination of:

  • Suspected or proven infection
  • Two or more of: HR >90, RR >20, T <36 or >38, WCC <4 or >12, altered mentation
  • Any sign of organ dysfunction: mottling, lactate >2, AKI, hypotension

Clinical pearl

The patient who looks "subtly off" with a normal blood pressure is the patient you miss. Mottling, agitation, and reduced urine output are early. Hypotension is late.

The bundle

Give 1 — High-flow oxygen

15 L/min via non-rebreathe mask in the unwell septic patient, then titrate down to SpO2 94-98% (88-92% if known CO2 retention).

Give 2 — IV broad-spectrum antibiotics

Within the first hour. The empirical choice depends on suspected source and local microbiology guidance — examples below; always check local guidelines.

Suspected sourceCommon UK empirical regimen
Community-acquired sepsis, source unclearPiperacillin-tazobactam 4.5 g IV
CAP, severeCo-amoxiclav + clarithromycin
Suspected meningitisCeftriaxone 2 g IV + dexamethasone
Neutropenic sepsisPiperacillin-tazobactam 4.5 g IV (within 1 hour, no delay for cultures)
Piperacillin-tazobactam4.5 gIV

Give 3 — IV fluids

Crystalloid (Hartmann's or Plasma-Lyte preferred over 0.9% saline). 500 mL bolus over 15 minutes, reassess. Up to 30 mL/kg in the first 3 hours in septic shock. Reassess perfusion after each bolus — JVP, lung bases, mottling, cap refill, mentation. Stop if no clear response or signs of pulmonary congestion.

Take 1 — Blood cultures

Two sets, ideally before antibiotics — but never delay antibiotics beyond a few minutes to get them. If a central line or port is in situ, take one set from there and one peripherally.

Take 2 — Lactate (and venous gas)

A VBG is fine for lactate, pH, base excess, and a quick Hb/electrolytes. Repeat at 2-4 hours.

Take 3 — Urine output

Catheterise if not already; aim for ≥0.5 mL/kg/h. This is your bedside renal-perfusion monitor.

Red flag

SBP <90 mmHg after 30 mL/kg of crystalloid, or lactate >4 mmol/L not improving — this is septic shock. The patient needs vasopressors (usually noradrenaline) and a level-2/3 bed. Escalate immediately.

What tends to slip

  • Antibiotic delay waiting for blood cultures that take 25 minutes to come back to. Two sets, ten minutes, then antibiotics.
  • No source control plan. A septic patient with a perforated viscus needs a surgeon, not a fourth fluid bolus.
  • Forgetting to reassess. A 30 mL/kg bolus is not the whole job. Lactate, mottling, mentation, urine output — recheck at 2 hours.

Key points

  • Recognise sepsis early; mottling and altered mentation beat blood pressure as warning signs.
  • The Sepsis-Six is a clock, not a checklist — antibiotics within an hour matter most.
  • Source control is part of the bundle in spirit, even if it isn't one of the six.
  • Reassess at 2 hours. If not improving, escalate.

References

  1. [1]UK Sepsis Trust. Toolkit: General Practice Management of Sepsis. Latest version, 2025. Link
  2. [2]Evans L, Rhodes A, Alhazzani W, et al. Surviving Sepsis Campaign 2021 Guidelines. Intensive Care Med. 2021;47(11):1181-1247. Link

About the author

Dr. Theo LindqvistVerifiedVerified medical practitioner

MBChB, FRCEM

Emergency Medicine· Royal London Hospital

Emergency medicine consultant with a teaching role for foundation and core trainees. Interests in resuscitation, sepsis, and time-critical decisions.

More in Emergency Medicine