Gastroenterology Surgery A

AIR Score for Appendicitis

Appendicitis Inflammatory Response (AIR) score — validated tool for stratifying patients with suspected appendicitis. Score 0–12.

Score interpretation

Low Risk — Appendicitis Unlikely 0–4

Low risk. Appendicitis unlikely (<5% in low-risk group).

→ Discharge with advice. Return if symptoms worsen. No imaging or admission required.

Intermediate Risk — Further Evaluation 5–8

Intermediate risk. Appendicitis possible (~38% prevalence).

→ Active observation (6–12 hours), serial labs, and CT or ultrasound abdomen. Surgical review.

High Risk — Appendicitis Likely 9–12

High risk. Appendicitis highly probable (~85–90%).

→ Surgical review for appendicectomy. CT may be omitted in typical presentations. IV access and pre-op bloods.

Interpretation bands for the AIR Score. Apply clinical judgement and local guidance.

Scott AJ et al. Prospective validation of the appendicitis inflammatory response score: the AIR score is a useful triage tool in patients with suspected appendicitis. Dis Colon Rectum. 2015;58(11):1056-1063.
de Burlet KJ et al. Prospective validation of the Appendicitis Inflammatory Response score for diagnosis of appendicitis in a New Zealand emergency department. ANZ J Surg. 2015;85(7-8):540-544.

Curated clinical cross-links plus same-class fallbacks.

Calculators

Drugs

Pathways

Decision support only — verify against a current formulary, NICE, or your local guideline before clinical use.