{
  "id": "ariscat-postoperative-pulmonary-complication-risk",
  "title": "ARISCAT Postoperative Pulmonary Complication Risk Index",
  "version": "Original seven-variable model · evidence package reviewed 2026-09-22",
  "lastReviewed": "2026-09-22",
  "intendedPopulation": "Adults undergoing noncardiac surgery; use only as clinician-facing decision support.",
  "formula": {
    "type": "additive-points",
    "maximumScore": 123,
    "variables": [
      { "id": "age_years", "label": "Age", "rules": [{ "condition": "<= 50", "points": 0 }, { "condition": "51-80", "points": 3 }, { "condition": "> 80", "points": 16 }] },
      { "id": "preop_spo2_percent", "label": "Resting preoperative SpO2", "rules": [{ "condition": ">= 96%", "points": 0 }, { "condition": "91-95%", "points": 8 }, { "condition": "<= 90%", "points": 24 }] },
      { "id": "respiratory_infection_last_month", "label": "Respiratory infection during the preceding month", "rules": [{ "condition": "no", "points": 0 }, { "condition": "yes", "points": 17 }] },
      { "id": "hemoglobin_g_dl", "label": "Preoperative anemia", "rules": [{ "condition": "> 10 g/dL", "points": 0 }, { "condition": "<= 10 g/dL", "points": 11 }] },
      { "id": "incision", "label": "Planned incision", "rules": [{ "condition": "neither upper abdominal nor intrathoracic", "points": 0 }, { "condition": "upper abdominal", "points": 15 }, { "condition": "intrathoracic", "points": 24 }] },
      { "id": "expected_duration", "label": "Expected procedure duration", "rules": [{ "condition": "< 2 hours", "points": 0 }, { "condition": "2-3 hours", "points": 16 }, { "condition": "> 3 hours", "points": 23 }] },
      { "id": "emergency_procedure", "label": "Emergency procedure", "rules": [{ "condition": "no", "points": 0 }, { "condition": "yes", "points": 8 }] }
    ],
    "riskBands": [
      { "label": "Low", "score": "< 26", "originalValidationCohortPpcIncidence": "1.6%" },
      { "label": "Intermediate", "score": "26-44", "originalValidationCohortPpcIncidence": "13.3%" },
      { "label": "High", "score": ">= 45", "originalValidationCohortPpcIncidence": "42.1%" }
    ]
  },
  "assumptions": [
    "Use actual preoperative measurements and the planned procedure.",
    "Do not add clinically important factors such as COPD, smoking, BMI, OSA, frailty, or spirometry to the original ARISCAT total.",
    "Interpret the output with the patient’s full cardiopulmonary context and local perioperative pathway."
  ],
  "limitations": [
    "ARISCAT is not a diagnosis, surgical-clearance tool, cancellation rule, or individualized probability calculator.",
    "Original-cohort risk-band incidences may not calibrate to every hospital, procedure, or patient population.",
    "The model does not replace anesthesiology, surgical, or perioperative evaluation."
  ],
  "sources": [
    { "id": "canet-2010-ariscat", "title": "ARISCAT derivation and validation", "citation": "Canet J, Gallart L, Gomar C, et al. Prediction of postoperative pulmonary complications in a population-based surgical cohort. Anesthesiology. 2010;113(6):1338-1350. doi:10.1097/ALN.0b013e3181fc6e0a. PMID: 21045639.", "url": "https://pubmed.ncbi.nlm.nih.gov/21045639/", "supports": ["seven-variable model", "score variables"] },
    { "id": "huang-2025-ppc-prediction-models", "title": "Postoperative pulmonary complication prediction-model review", "citation": "Huang Z, Han Y, Zhuang H, et al. Prediction models for postoperative pulmonary complications: a systematic review and meta-analysis. Br J Anaesth. 2025;135(5):1415-1427. doi:10.1016/j.bja.2025.04.025. PMID: 40473567; PMCID: PMC12597335.", "url": "https://pmc.ncbi.nlm.nih.gov/articles/PMC12597335/", "supports": ["external-performance caveat", "moderate discrimination"] },
    { "title": "Preoperative pulmonary evaluation review", "citation": "Comprehensive Strategies for Preoperative Pulmonary Risk Evaluation and Management. 2025. PMCID: PMC11704732.", "url": "https://pmc.ncbi.nlm.nih.gov/articles/PMC11704732/", "supports": ["risk-score context", "preoperative assessment"] },
    { "id": "odor-2020-ppc-prevention", "title": "Perioperative PPC-prevention review", "citation": "Odor PM, Bampoe S, Gilhooly D, et al. Perioperative interventions for prevention of postoperative pulmonary complications: systematic review and meta-analysis. BMJ. 2020;368:m540. doi:10.1136/bmj.m540. PMID: 32161042; PMCID: PMC7190038.", "url": "https://www.bmj.com/content/bmj/368/bmj.m540.full.pdf", "supports": ["optimization-content context"] }
  ],
  "webResource": "https://pulmtools.com/resources/preoperative-pulmonary-risk"
}