Risk stratification tool for adults, children and young people aged 12 years and over with suspected sepsis

Overview

• risk evaluation for adults, children, and young people aged 12 years and over with suspected sepsis relies on clinical examination, physiological cut-offs, and risk factors (1)
• guidance in NICE NG253 updates community risk criteria, incorporates vulnerability factors, and provides pre-hospital antibiotic protocols (1)

Vulnerability Factors for Severe Sepsis when evaluating patients with suspected infection, consider a lower threshold for clinical concern and escalation if any of the following vulnerability parameters are present (1):

• age >= 75 years
• comorbidities and frailty: multimorbidity, moderate-to-severe frailty, or cognitive impairment
• immunosuppression: active chemotherapy, systemic corticosteroids, non-cancer immunosuppressive therapies, or organ transplant recipients
• invasive factors: indwelling urinary catheters, surgical/procedural interventions in the last 6 weeks, or breaches in skin integrity
• social and health inequalities: significant socio-economic deprivation, substance misuse, or communication difficulties (for example non-native language, neurodiversity, learning disability)

Risk Stratification Criteria

High Risk Criteria adults, children, and young people aged 12 years and over with suspected sepsis presenting with any of the following are at high risk of severe illness or death (1):

• objective evidence of new altered mental state
• respiratory rate >= 25 breaths/min, or new need for >= 40% oxygen to maintain oxygen saturation > 92% (or > 88% in chronic hypercapnic respiratory failure)
• heart rate > 130 beats/min
• systolic blood pressure <= 90 mmHg, or a drop > 40 mmHg below normal baseline
• anuria or no urine output in previous 18 hours (for catheterized patients, < 0.5 ml/kg/hour)
• mottled or ashen appearance
• cyanosis of skin, lips, or tongue
• non-blanching rash

Moderate Risk Criteria patients presenting with any of the following without high-risk criteria are at moderate risk:

• respiratory rate 21–24 breaths/min
• heart rate 91–130 beats/min or new onset arrhythmia
• systolic blood pressure 91–100 mmHg
• no urine output in the past 12–18 hours
• signs of spreading skin/wound infection or breakdown

Primary Care Management and Escalation Pathways

High Risk

• arrange immediate emergency transfer via 999 ambulance to an Emergency Department
• administer oxygen if hypoxaemic (target saturation 94–98%, or 88–92% in chronic hypercapnic respiratory failure)
• pre-hospital antibiotics: if transfer and handover times to hospital are anticipated to exceed 1 hour (for example rural settings), primary care clinicians should administer an initial dose of parenteral broad-spectrum antibiotics prior to transfer where local protocols allow (2)

Moderate Risk

• arrange urgent face-to-face medical evaluation
• determine whether care can be safely managed in the community or requires secondary assessment based on clinical trajectory, diagnostic facilities, and social support
• provide explicit safety netting instructions including deterioration red flags

Low or Very Low Risk

• provide symptom management and structured safety-netting advice on when and how to seek urgent secondary review if symptoms worsen

References

1. National Institute for Health and Care Excellence (NICE). Suspected sepsis in people aged 16 or over: recognition, assessment and early management (NG253). Published Nov 2025, updated Sep 2026 (supersedes NICE NG51).
2. UK Sepsis Trust. The Sepsis Manual. General Practice recognition & management of Sepsis in adults and children and young people over 12 years. 7th edition. 2024.