Shoulder and head elevation improves laryngoscopic view for tracheal intubation in nonobese as well as obese individuals

J Clin Anesth. 2012 Mar;24(2):104-8. doi: 10.1016/j.jclinane.2011.06.015. Epub 2012 Feb 1.


Study objective: To determine whether shoulder and head elevation, such that the patient's ear lies at or higher than the sternum ("ramp"), improves laryngoscopic grade in adult patients of various body mass index (BMI) values.

Design: Prospective, unblinded study, with patients and laryngoscopists acting as their own controls.

Setting: Operating room of a university-affiliated hospital.

Patients: 189 adult ASA physical status 1, 2, and 3 patients.

Interventions: After performing a standard preoperative airway evaluation and inducing general anesthesia, the anesthetist performed and graded two laryngoscopies: one in the "ramp" position and one in the "sniff" position.

Measurements: Patient BMI, Mallampati airway class, thyromental distance, neck circumference, cervical extension ability, Cormack and Lehane laryngoscopic grade for each laryngoscopy, subjective lifting force required, and need for external laryngeal pressure were recorded.

Main results: Use of the "ramp" provided significantly better or equal laryngoscopic views, relative to those with the "sniff" position, in the entire study population.

Conclusions: Shoulder and head elevation by any means that brings the patient's sternum onto the horizontal plane of the external auditory meatus maintains or improves laryngoscopic view significantly.

Publication types

  • Comparative Study
  • Controlled Clinical Trial
  • Research Support, Non-U.S. Gov't

MeSH terms

  • Adult
  • Anesthesia, General / methods
  • Body Mass Index
  • Head
  • Hospitals, University
  • Humans
  • Intubation, Intratracheal / methods*
  • Laryngoscopy / methods*
  • Obesity / complications*
  • Obesity, Morbid / complications
  • Posture*
  • Shoulder
  • Sternum