POCUS - Abdominal Aortic Pathologies
Practical ED/resuscitation guidance for bedside aortic ultrasound. Covers indications, scanning technique, measurement and reporting conventions, integration with acute care (including suspected rupture and intra‑arrest use), and local governance/training considerations. Aligned with NICE NG156, NHS AAA Screening Programme and RCEM POCUS guidance.
Why do this scan?
Point‑of‑care aortic ultrasound is the fastest reliable bedside test to detect an abdominal aortic aneurysm (AAA) and to trigger urgent vascular escalation in unstable patients. It is operator‑dependent and cannot reliably exclude rupture or replace CT angiography for operative planning in stable patients.
Definitions and size thresholds
- Normal abdominal aorta: approximately 2.0 cm (varies with habitus).
- AAA (NICE/NHS screening convention): maximum anterior-posterior (AP) diameter ≥ 3.0 cm measured inner‑to‑inner.
- Common iliac aneurysm: often considered at ≥ 1.5 cm.
Escalation (NICE‑aligned):
- 3.0-5.4 cm: surveillance / expedited outpatient vascular assessment (local timing pathways apply).
- ≥ 5.5 cm or growth >1.0 cm in 12 months: urgent vascular referral for consideration of repair (NICE target: specialist review within 2 weeks).
- Measurement convention: use inner‑to‑inner AP measurement by default for reporting and referral. If your department uses a different convention (outer‑to‑outer), state it clearly and harmonise with regional vascular services.