critical care medicine
Tracheal Intubation
Tube Selection and Preparation for Intubation
Most adults can accept a tube with an internal diameter of≥8 mm; these tubes are preferable to smaller ones because they Have lower airflow resistance (reducing the work of breathing) Facilitate suctioning of secretions Allow passage of a bronchoscope May aid in liberation from mechanical ventilation For infants and children≥1 year, uncuffed tube size is calculated by (patient’s age+16)/4; thus, a 4-year-old should have a (4+16)/4=5 mm endotracheal tube. The tube size suggested by this formula should be reduced by 0.5 (1 tube size) if a cuffed tube is to be used. Reference charts (see table) or devices such as the Broselow pediatric emergency tape or Pedi-Wheel can rapidly identify appropriate-sized laryngoscope blades and endotracheal tubes for infants and children. For adults (and sometimes for children), a rigid stylet should be placed in the tube, taking care to stop the stylet 1 to 2 cm before the distal end of the endotracheal tube, so that the tube tip remains soft. The stylet should then be used to make the tube straight to the beginning of the distal cuff; from that point, the tube is bent upward about 35°to form a hockey stick shape. This straight-to-cuff shape improves tube delivery and avoids blocking the operator’s view of the vocal cords during tube passage. Routinely filling the distal endotracheal tube cuff with air to check the balloon is not required; if this technique is used, care must be taken to remove all the air before tube insertion. 