The clinician then 'scissors' the patient's mouth open, crossing the thumb and middle finger. The scissoring technique involves placing the right thumb on the right middle finger and inserting the right hand into the patient's mouth. Īfter allowing the paralytic agents to take effect after 60 seconds, the patient's mouth should be opened with the scissoring technique. The clinician performing the rapid sequence intubation should ensure a tight seal of the bag valve mask to the patient's face. Once the patient, supplies, and team have been properly prepared, induction agents can be administered to the patient first, followed by paralytic agents. The bag valve mask should be utilized to pre-oxygenate the patient as much as possible. However, below are two charts of the frequently used induction and paralytic agents and their differing characteristics. A Miller blade is flat and designed to go over the epiglottis to reveal the vocal cords.Īn in-depth discussion on the agents used to induce and paralyze patients undergoing RSI is outside the scope of this article. The Macintosh blade should be placed inside the vallecula at the base of the tongue. A Macintosh 4 blade is 15.5-cm and allows the practitioner a longer blade to utilize if necessary. A Macintosh 3 has a 13-cm blade and fits most average-sized adults. The Macintosh blade has a curved spatula used to approximate the curvature of the tongue and move the epiglottis, mandible, hyoid bone, and other soft tissues out of the view of the glottis. The most commonly used laryngoscope blades are the Macintosh and Miller blades. Smaller tube sizes are not adequately large enough to perform a bronchoscopy if it becomes necessary. Generally, a 7.0 to 7.5 mm internal diameter size tube should be placed in a female patient, and a 7.5 to 8.0 mm tube should be placed in a male. An easily viewed pulse oximeter should be available. The clinician should test the lighting source on the laryngoscope and test the inflation of the endotracheal tube. Successive grades reveal less of the cords and have a decreased rate of successful intubation.īefore initiating the procedure, the clinician should make sure that the lighting in the room is adequate.

In this grade, the provider can see nearly the entirety of the vocal cord anatomy. A Grade 1 view of the cords using this system indicates a high likelihood of successful intubation. The Cormack and Lehane Grading system allow the provider to evaluate their view of the vocal cord and estimates the chance of successful intubation. When intubating with a Macintosh blade (discussed later), the tip of the blade should ideally be placed at the base of the tongue in the vallecula, and a ventral and inferior movement of the blade reveals the vocal cords. The valley between the tongue and the epiglottis is called the vallecula.

The origin of the epiglottis can be found at the base of the tongue. The epiglottis serves as the primary landmark that will direct successful endotracheal intubation. This position is called the 'sniffing position.' This allows for the best visualization of the anatomy, including the epiglottis and vocal cords. Ideally, the neck should be flexed at the lower cervical spine (C6-C7) and extended at the upper cervical spine (C1-C2). Proper positioning of the patient is vital to the success of the procedure. Obstruction of the airway, including head and neck cancer, epiglottitis, can indicate a difficult airway.Ī neck that cannot be maneuvered into an ideal position due to trauma, c-collar, or rigidity can lead to a more difficult airway. Obesity (body mass index > 30) can be a predictor of a difficult airway. Mallampati 4 score indicates that the uvula cannot be visualized.Ī higher Mallampati score is an indication of a more difficult airway.

Rapid sequence intubation process