Introduction

 

 

Immediate provision of a patent airway and adequate ventilation and oxygenation are the major aims of successful cardiopulmonary resuscitation (CPR) in nonbreathing and unconscious patients. Bag-valve-mask ventilation may be effective, but not easy to perform and not safe in an unprotected airway. Although tracheal intubation was for many years the gold standard for airway management in emergency situations, it may be difficult or impossible even when performed by experienced operators.

 

The method of esophageal obturation (as an alternative to tracheal intubation) with the esophageal obturator airway (EOA) for securing the airway and rescue ventilation in emergency situations was first communicated by Don Michael (1) in 1968. The commercially available EOA was a single-lumen tube with a balloon at the distal closed rounded end (in order to block the esophagus and minimizing the risk of pulmonary aspiration of gastric contents), an anatomically moulded face mask at the proximal end (for providing an air-tight seal) with a conventional tracheal tube connector, and with multiple openings at the hypopharyngeal level (for ventilation of the lungs). When the EOA was correctly placed deep into the esophagus, the patient could be ventilated through the openings in the tube provided free laryngeal access.

 

In November 1981, Michael Frass, at this time just starting with his residency training in internal medicine at the Medical University of Vienna (Vienna, Austria), together with Jonas Zahler, staff internal medicine physician at the same institution, had the idea to redesign the single-lumen EOA for rescue ventilation; two years later, Reinhard Frenzer added significantly to the design and prototype of the new airway device. Their activities culminated in the invention of the double-lumen esophageal-tracheal combitube (ETC) for easy and safe control of the airway and ventilation in emergency situations (2). In June 1987, Frass and co-workers published their early clinical experiences with ETC prototypes for ventilation and oxygenation during CPR in the journal Critical Care Medicine (5).

 

 

Publications of the Experiences with Prototypes