Table 4.

Observed failure modes for all methods of fixation

Mode	SolidAIRity®	Thomas™	Anchor Fast	Tape & Mallinckrodt tube	Twill & Mallinckrodt tube	Tape & Securisyn tube	Twill & Securisyn tube
1	Tube slipped through stabilizer: Ribs on the tube would deform and flatten out enough to slide through the stabilization device. Loading from any angles except center would sometimes cause the stabilizer parts to separate (splay) enough for the tube to slip through (Test points 1, 2, 3, 4, 6, 9, 11, 12).	Tube slipped through clamp: This mode of failure did not result in any damage to the device rather it just failed to prevent tube motion by allowing the tube to slide through the clamp mechanism.	Clip broke at attachment point of sliding member: A feature for lateral adjustment of tube placement is included with this device. It consists of a clip that slides along a bar. This clip would fail catastrophically, with pieces breaking off (test points 1, 2, 3, 4, 6, 7, 8, 9, 11).	Tape tore between tube and cheek: All angles demonstrated same failure mechanism of tape tearing.	Knot lost Tension: All failures were the same.	Tape tore between tube and cheek or at tape-tube interface: All angles demonstrated same failure mechanism of the tape tearing where it came in contact with the ribs of the ET tube.	Knot lost Tension: All tests that failed exhibited a gradual loss in knot tension and progressive slipping of the tube through the knot. Certain angles allowed the knot to maintain tension generating very large force values (test points 2, 7, 9, 11).
2	Depending upon angle of force application, at very large loads (>200 N) sometimes the entire stabilization device would fail by cracking of the plastic stabilization pieces (Test points 5, 7, 8, 10, 13).		Clip slid off bar: Alternatively, the clip mechanism would fail by sliding off the end of the bar on which it travels (test point 13) or both slide off and break (test point 10).

Description of failure modes for all methods of ET tube fixation.