Comparison of the Length and Shape of Various Preformed Nasotracheal Tubes
We aimed to investigate the differences in the lengths and shapes of several preformed nasotracheal tubes (NTTs) among different manufacturers and compare our findings with a previous report. Using reference points at the tube tip, the proximal edge of the cuff, and the flexion point, we measured tube lengths for NTTs with inner diameters of 6.5, 7.0, and 7.5 mm from 4 manufacturers: the Parker Preformed Cuffed Endotracheal Tube (Parker), the Medtronic Taper Guard RAE (RAE), the Rusch AGT Nasal Preformed Cuffed Endotracheal Tube, and the Portex Polar Preformed Tracheal Tube. Cuff lengths and shapes were also assessed. A historical comparison was then performed using a previous report from 2012. The effective lengths (distance between tube tip and flexion point) were largest for the Parker tubes (295-315 mm). The RAE and Rusch tubes had the shortest effective lengths (270-290 mm). Cuff lengths ranged from 30 to 39 mm, and cuff shapes were cylindrical, tapered, and oval. Comparison with the past data revealed substantial changes in tube lengths for Parker and RAE tubes, modest increases in cuff lengths, and a change in cuff shape from oval to tapered in RAE tubes. Several changes in tube lengths and cuff lengths/shapes were noted among manufacturers relative to the historical data. These findings demonstrate that manufacturer specifications can change over time. In dentistry and oral surgery, Parker tubes may be more ideal due to their longer effective lengths because extension and/or rotation of the neck can decrease NTT insertion depth.Objective
Methods
Results
Conclusion
Tube Length Measurements
Effective length (A + B) extended from the tube tip to the flexion point. A, Length between the tube tip and the proximal edge of the cuff; B, length between the proximal edge of the cuff and the flexion point.
Cuff Length Measurements
Cuffs were inflated to a pressure of 20 cm of H2O. Cuff length, length from the distal to the proximal cuff edges. Tube types: (a) Parker; (b) RAE; (c) Rusch; and (d) Polar.
Index Depth Markers
Parker and Polar have index depth markers to identify the cuff’s depth relative to the glottis. Parker tubes have 2 lines (double black arrows) and Polar tubes have 1 line (single black arrow). The other tubes have no index depth marker.
Contributor Notes
Drs Nakamura, Kobayashi, and Ouchi contributed equally to this work.