Evaluation of pressure changes in a new design tracheal tube cuff, the Porter Soft Seal, during nitrous oxide anaesthesia

We have measured pressure changes in a newly designed tracheal tube cuff, the Porter Soft Seal, during nitrous oxide anaesthesia compared with a Mallinckrodt Lo-Contour tube and a Porter Profile tube. The pressure increases in both control groups were significantly greater than those with the new design (P<0.0001 in each case). The mean increase in pressure in the Mallinckrodt Lo-Contour tube cuff was 9.9 (SD 3.4) mm Hg compared with 10.3 (1.8) mm Hg in the Porter Profile tube cuff and 2.1 (1.5) mm Hg in the Porter Soft Seal tube cuff. We conclude that the Porter Soft Seal cuff prevented a significant increase in intracuff pressure during nitrous oxide anaesthesia.