Abukawa Y, Hiroki K, Iwakiri H, Fukuda T, Ozaki M. J Anesth. 2016;30(2):199-204
130 patients aged 7 months to 13 years monitored under general anaesthesia, with size selection based on patient's body weight. Average insertion length grew longer with increasing height and weight. Authors conclude a line could be drawn on sizes 1.5 and 2 only.
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