Dear Sir,
A 2 day old premature (36 week) female neonate presented to our hospital with intestinal obstruction for which she was to undergo laparatomy. Based on standard formulas, we assumed that a size 2.5 or a 3.0 mm internal diameter endotracheal tube would be suitable for her. But upon intubation, we could hear a significant leak with both tubes and were unable to ventilate. We then tried a 3.5 mm tube but the same amount of leak persisted. Finally, we put in a size 4.0 endotracheal tube and noticed very acceptable leak and normal ventilatory pressures with it. We want to highlight the fact that in premature neonates, the elasticity of laryngeal structures permits intubation with tube sizes greater than that predicted by anatomical measurements.1 Hence, endotracheal tube sizes greater than that predicted by measurements should be available in the theatre especially in premature babies.2
REFERENCES
- 1.Fayoux P, Devisme L, Merrot O, Marciniak B. Determination of endotracheal tube size in a perinatal population: an anatomical and experimental study. Anesthesiology. 2006 May;104(5):954–60. doi: 10.1097/00000542-200605000-00011. [DOI] [PubMed] [Google Scholar]
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