{"uid":"cap_n1s9OrevIQD4pq0b9b1kW","slug":"cole-1957-pediatric-endotracheal-tube-ett-size-calculator-dc4d618d","name":"Cole 1957 Pediatric Endotracheal Tube (ETT) Size Calculator","description":"Cole 1957 uncuffed pediatric endotracheal tube internal diameter: age_years/4 + 4 millimetres. Deterministic published arithmetic with citation; not a device-selection order or length-based tape.","url":"https://api.magentlab.com/api/calc/pediatric_ett","method":"GET","headers":{},"bodySchema":{"type":"object","$schema":"https://json-schema.org/draft/2020-12/schema","required":["input"],"properties":{"input":{"type":"object","required":["type","method"],"properties":{"type":{"type":"string","const":"http"},"method":{"enum":["GET","HEAD","DELETE"],"type":"string"},"headers":{"type":"object","additionalProperties":{"type":"string"}},"queryParams":{"type":"object","required":["age_years"],"properties":{"age_years":{"type":"number","description":"Age in years (0.5-12). Cole uncuffed ID (mm) = age/4 + 4. Not a neonatal-only formula."}}}},"additionalProperties":false},"output":{"type":"object","required":["type"],"properties":{"type":{"type":"string"},"example":{"type":"object"}}}}},"responseSchema":{"type":"json","example":{"path":"/api/calc/pediatric_ett","count":2,"items":[{"formula":"cole_1957","citation":{"id":"cole-1957","doi":"10.1001/archpedi.1957.04030070084009","title":"Pediatric formulas for the anesthesiologist","source":"AMA Am J Dis Child. 1957;94(6):672-673","authors":"Cole F"},"age_years":4,"ett_id_mm":5,"disclaimer":"Not a medical device. Deterministic published-formula or published-code output for autonomous agents. A licensed clinician remains responsible for patient care and billing submissions.","formula_expression":"ett_id_mm = age_years / 4 + 4"},{"formula":"cole_1957","citation":{"id":"cole-1957","doi":"10.1001/archpedi.1957.04030070084009","title":"Pediatric formulas for the anesthesiologist","source":"AMA Am J Dis Child. 1957;94(6):672-673","authors":"Cole F"},"age_years":4,"ett_id_mm":5,"disclaimer":"Not a medical device. Deterministic published-formula or published-code output for autonomous agents. A licensed clinician remains responsible for patient care and billing submissions.","formula_expression":"ett_id_mm = age_years / 4 + 4"}]}},"example":null,"exampleRequest":null,"tags":["x402"],"displayCostAmount":"0.005","displayCostAsset":"USDC","priceDynamic":false,"priceHint":null,"priceStatus":"priced","priceSource":"probe","requiresHandshake":false,"reviewCount":0,"rating":{"score":"0.00","successRate":"0.00","reviews":0,"stars":null,"state":"unrated"},"availabilityStatus":"unknown","priceObserved":null,"sessionDeposit":null,"pricing":{"kind":"static","summary":"$0.005/call","primary":{"kind":"static","protocol":"x402","network":"base","amountUsd":"0.005","per":"call","confidence":"exact"},"accepted":[{"kind":"static","protocol":"x402","network":"base","amountUsd":"0.005","per":"call","confidence":"exact"}]},"paymentMethods":[{"uid":"pm_0YLt9eqFhEaRph_qnd0sS","protocol":"x402","methodType":"crypto","chain":"base","mode":"charge","costAmount":"0.005","costPer":"request","priority":0,"asset":"0x833589fCD6eDb6E08f4c7C32D4f71b54bdA02913","unit":"request","depositMicros":null,"planRef":null}],"brandName":null,"brandSlug":null,"brandBaseUrl":null,"brandDocsUrl":null,"whatItDoes":"Calculates the recommended uncuffed pediatric endotracheal tube internal diameter in millimetres using the Cole 1957 formula: age_years/4 + 4","exampleAgentPrompt":"What's the correct uncuffed endotracheal tube internal diameter for a 5-year-old child using the Cole formula?","exampleUseCases":[{"title":"Emergency pediatric intubation sizing","prompt":"I need to intubate a 3-year-old — what uncuffed ETT internal diameter does the Cole formula recommend?"},{"title":"Anesthesia pre-op tube selection","prompt":"For a 7-year-old scheduled for surgery, calculate the Cole 1957 uncuffed endotracheal tube size so I can prepare the right equipment."},{"title":"Pediatric PALS protocol reference","prompt":"Can you give me the Cole formula ETT internal diameter for an 8-year-old patient? I need it for the airway kit checklist."}],"resultDescription":"Returns the calculated uncuffed endotracheal tube internal diameter in millimetres computed as age_years/4 + 4, based on the Cole 1957 published formula. The result is a deterministic arithmetic output with a citation and does not represent a device order or length-based tape measurement.","failureModes":["Age out of range (below 0.5 or above 12 years): formula is not validated for neonates or older adolescents","Missing required age_years query parameter: returns a validation error","Non-numeric or negative age input: returns a schema validation error","Network/payment failure (x402 micropayment not fulfilled): request not processed"],"whenToPreferThis":"Use this endpoint when you need a fast, authoritative, citation-backed arithmetic calculation of uncuffed pediatric ETT internal diameter by age (Cole 1957 formula, valid for ages 0.5–12 years). Prefer this over manual calculation to eliminate arithmetic errors in clinical workflows. Not suitable for neonatal tube sizing, cuffed tube selection, or length-based (Broselow tape) estimations.","instructions":null,"reviewSummary":null,"reviewSummaryHighlights":null,"reviewSummaryConcerns":null,"reviewSummaryGeneratedAt":null,"activationCount":0,"lastUsedAt":null,"lastSuccessfullyRanAt":null,"lastHealthCheckAt":"2026-09-15T01:14:45.110Z","isFirstParty":false}