Ultrathin-wall, two-stage, twin endotracheal tube: a tracheal tube with minimal resistance and minimal dead space for use in newborn and infant patients

Pediatr Crit Care Med. 2004 Jul;5(4):379-83. doi: 10.1097/01.pcc.0000128602.22489.2d.


Objective: To design and fabricate crush-proof polyurethane tracheal tubes for the newborn with the lowest resistance, least dead space, and thinnest wall.

Design: Test and evaluation of a novel, low-resistance, and low-dead-space tracheal tube for newborns.

Setting: National Institutes of Health Research Laboratory.

Interventions: The short orotracheal portion of the tracheal tube was fabricated of polyurethane, reinforced with flat nickel-titanium shape-memory alloy (Nitinol) to render the tube crush-proof, of a wall thickness about one half of a standard tracheal tube. To the oral part of the tracheal tube, which is the sole dead-space, we attached a Y piece. We connected to one arm of the Y a nonreinforced (inspiratory) tube of larger internal diameter, and a similar tube (expiratory) to the other.

Measurements and results: The computed air flow resistance, as derived from the pressure/flow curves, is about one half to one third the resistance of a comparable standard tracheal tube at flow rates up to 8 L/min, with a tubing, connector, and adapter dead space three to seven times smaller, depending on the tracheal tube connector piece, the ventilator tube connector piece, and size of the tracheal tube.

Conclusions: The novel tracheal tube design has a resistance to gas flow one half to one third that of a standard tracheal tube and a dead-space volume three to seven times lower, including tubing and connector dead space. In addition, it offers a means for potential accurate, continuous online monitoring of expiratory oxygen and Co(2) concentration and gas flow, in both the inspiratory and the expiratory lines, without contributing to dead-space ventilation or gas flow resistance.

Publication types

  • Research Support, U.S. Gov't, P.H.S.

MeSH terms

  • Alloys
  • Equipment Design
  • Humans
  • Infant
  • Infant, Newborn
  • Intubation, Intratracheal / instrumentation*
  • Materials Testing
  • Polyurethanes


  • Alloys
  • Polyurethanes
  • nitinol