Endotracheal tubes (ET) tubes with high-volume, low-pressure cuffs are the best design for adults. When properly inflated, thin-walled cuffs prevent aspiration better than medium-walled cuffs. The operator should test the light on the laryngoscope and then pick an appropriate sized blade. The straight Magill blade physically lifts the epiglottis. The curved Macintosh blade rests in the vallecula above the epiglottis and indirectly lifts the epiglottis off the larynx owing to the traction on the frenulum.
The development of expertise with both blades is desirable, since they offer differing advantages, depending on the clinical setting and the patient's body habitus. The curved blade may cause less trauma and be less likely to stimulate an airway reflex since it does not directly touch the larynx. It also allows more room for adequate visualization during tube placement and is helpful in the obese patient. The straight blade is mechanically easier to insert in many patients who do not have large central incisors. Simply point the tip of the blade directly at the epiglottis and aim for it. Selecting the proper-size blade greatly facilitates intubation. In adults, the curved Macintosh no. 3 is the most popular, or no. 4 for large patients. The straight Miller no. 2 or 3 is similarly most often ideal.
When all equipment is in order, the patient should be placed in the sniffing position. Flexion of the lower neck with extension at the atlantooccipital joint (sniffing position) aligns the oropharyngeolaryngeal axis, allowing a direct view of the larynx. Placing a folded towel or small pillow under the occiput is often helpful ( Fig 15-1). The inexperienced laryngoscopist's most common reasons for failure—inadequate equipment preparation and poor patient positioning—arise prior to the use of the laryngoscope.
Was this article helpful?
Studies show obesity may soon overtake tobacco as the leading cause of death in world. Who Else Could Use 101 'Everyday' Ways to Lose 10 Pounds or more and Keep it Off! You've been putting it off too long. Hey, everyone needs to lose weight from time to time. You're no different!