Krishaber Tracheotomy Fig mm 0 4 Y17.150.04 1 5 Y17.150.05 2 6 Y17.150.06 3 7 Y17.150.07 4 8 Y17.150.08 5 9 Y17.150.09 6 10 Y17.150.10 7 11 Y17.150.11 8 12 Y17.150.12