Cricothyrotomy technique: standard versus the rapid four-step technique

Abstract

Standard cricothyrotomy technique uses a tracheal hook cephalad to the opening to stabilize the trachea during endotracheal (ET) tube passage. A newly described Rapid Four-Step Technique (RFST) uses the tracheal hook caudal to the opening to stabilize the trachea during ET tube passage. This experimental crossover trial compared standard cephalad tracheal hook traction to caudad traction as recommended by RFST in a cadaver model of cricothyrotomy. Outcome measures included the incidence of complications and the size of ET tube able to be passed with each technique. The anterior necks of 30 formalin-fixed cadavers were dissected to completely reveal the cricothyroid membranes and surrounding structures. Two emergency medicine residents performed all cricothyrotomies. Each cadaver was randomly assigned to undergo either standard open technique followed by RFST, or RFST followed by standard open technique. Standard open technique was performed using a #11 scalpel blade, a Trousseau dilator for widening the opening, and a tracheal hook held cephalad through the thyroid cartilage. RFST was performed using a #11 scalpel blade and a tracheal hook held caudad through the cricoid cartilage. Cuffed ET tubes without stylettes were passed in progressively larger sizes until significant resistance was met as determined independently by two physicians. The size of the largest ET tube passed for each technique was recorded. After each attempt the trachea was inspected for evidence of structural damage and the balloon cuff was checked to assess for cuff rupture. There were no complications with standard technique; five cadavers (16.7%) had complications with RFST including one (3.3%) with balloon cuff rupture and four (13.3%) with cricoid cartilage fractures. Tracheal damage prevented standard technique performance on three of the cadavers. There was no significant difference between maximal ET tube sizes for standard technique (median size 7.0, mean 6.95 mm internal diameter) versus RFST (median size 7.0, mean 6.82 mm internal diameter). We conclude that RFST may be associated with a higher incidence of complications than standard technique as demonstrated by our cadaver model of cricothyrotomy. We were unable to demonstrate a difference between the two techniques with regards to size of ET tube able to be passed.