During emergency anesthesia (rapid sequence induction) , a firm pressure is applied to the cricoid cartilage of the patient in order to prevent passive regurgitation of gastric content into the pharynx. This maneuver is called cricoid pressure.

Cricoid pressure is often performed incorrectly, due to difficulties to locate the cricoid cartilage in many patients. Despite this, the effectiveness of an incorrectly applied cricoid pressure has not been investigated. In this study we have used high-resolution manometry (HRM) to evaluate pressures in the upper esophagus during correctly applied cricoid pressure (against the cricoid cartilage) compared to incorrectly applied cricoid pressure (against the thyroid cartilage and against the trachea) during a rapid sequence induction.

Inclusion Criteria:

• Elective surgery and Anesthesia with intubation,
• ASA physical status I-II (American Society of Anesthesiologist classification system = system for assessing the fitness of cases before surgery)
• Body Mass Index > 18,5 and < 30
• Informed, signed and dated consent

Exclusion Criteria:

• Suspected difficult airway,
• Pharyngoesophageal dysfunction,
• Body Mass Index < 18,5 or > 30,