The PTL, Combitube, laryngeal mask, and oral airway: a randomized prehospital comparative study of ventilatory device effectiveness and cost-effectiveness in 470 cases of cardiorespiratory arrest

Abstract

Purpose: A prehospital study was conducted to assess and compare three alternative airway devices and the oral airway for use by non-Advanced Life Support emergency medical assistants (EMAs).

Method: A modified randomized crossover design was used. The Pharyngeal Tracheal Lumen Airway (PTL), the laryngeal mask (LM), and the esophageal tracheal Combitube (Combi) were compared objectively for success of insertion, ventilation, and arterial blood gas and spirometry measurements performed upon hospital arrival. Subjective assessment was carried out by EMAs and receiving physicians at the time of device use, and an eight-question comparative evaluation of all devices was completed by EMAs at study conclusion. A comparative cost analysis was performed. Operating room training was compared with mannequin training for the LM. Autopsy findings and survival to hospital discharge were analyzed. The study took place in four non-ALS communities over four and a half years, and involved 470 patients in cardiac and/or respiratory arrest. EMAs had automatic external defibrillator training but no endotracheal intubation skills.

Results: Successful insertion and ventilation: Combi, 86%; PTL, 82%; LM, 73% (p = 0.048). No significant difference was found for objective measurements of ventilatory effectiveness (ABGs and spirometry). Significant comparative differences in subjective evaluation were found.

Conclusions: The PTL, LM, and Combi appear to offer substantial advances over the OA/BVM system. Although the most costly, the Combitube was associated with the least problems with ventilation and was the most preferred by a majority of EMAs.