Figure 2

Cuff pressure according to method of assessment. Values are shown as median (25/75 percentiles) in cmH₂O (n = number of cases). Cuff pressure not checked: 70 (47.3/102.8) cmH₂O (n = 46); palpatory method: 43 (20.0/86.5) cmH₂O (n = 10); specific volume of air: 35 (17.5/85.0) cmH₂O (n = 14); cuff pressure manometer: 27 (20.0/30.0) cmH₂O (n = 22); acoustic method: 18 cmH₂O (n = 1). Dashed line indicates the upper safe cuff pressure limit. p < 0.001 for comparison of checked by manometer vs. not checked.