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Entonox contraindication in pneumothorax — DIPIMC MCQ

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HardPharmacology (Pre-Hospital)Entonox contraindication in pneumothoraxDIPIMCDipIMC

A patient with blunt chest trauma and a suspected pneumothorax is in pain, and the crew are considering analgesia. Entonox is available.

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Correct answer: E — Avoid Entonox, which can expand a pneumothorax, and titrate an intravenous opioid or ketamine instead

Entonox contains nitrous oxide, which diffuses into and expands air-filled spaces, so it is contraindicated where there is a pneumothorax and an intravenous opioid or ketamine should be titrated instead. Giving Entonox at any concentration (A and D) risks enlarging the pneumothorax, potentially into a tension. Other contraindications to nitrous oxide include bowel obstruction and decompression illness.

Reference: JRCALC Clinical Guidelines