I work at the same service as Adam. As he said we have had both the LMA and Combitube on board for about two years. In that time I have used the Combitube four times in the field. All four patients were trauma patients requiring RSI. I have never attempted to use the LMA. In all four of my combitubed patients, I was able to easily protect the airway as well as achieve good respiratory control.
Obviously we all agree that ET tubes are the standard for airway control in the trauma patient. In my experience, the Combitube has worked well as a backup. I think it is important to consider how fast a Combitube can be properly placed. As Mr. Copeland alluded to in his reply, many of our patients are suffering from multiple injuries thus scene time and ultimately transport time to the proper facility is significant. I have found that a Combitube can be placed and confirmed within a very short period of time. The Combitube is also nearly self securing. Once the cuff and balloon are inflated, there is very little chance of displacement.
In Adam's response, he mentioned the fact that gastric fluids can be evacuated through a Combitube that is placed in the esophagus (approx. 90%). I have had good results connecting the distal lumen directly to the suction hose via the provided swivel adapter and operating the suction unit as needed. On one of my flights, I was able to remove approximately 800 cc's of fluid (Bud Light) in about 3 minutes while continuing to ventilate the patient.
Another consideration with the Combitube is the additional "dead space" created in the patient's respiratory system. In the 90% patient group (including all four of mine) an additional "dead space" that becomes part of the airway is created between the distal cuff and the balloon. This may require additional tidal volume to adequately ventilate the patient. On my flights, I found that that the capronographer (as well as the other monitoring equipment) worked well to provide relevant feedback.
One final note relevant to this discussion: During a recent ACLS class, I had a conversation with an anesthesiologist that was very familiar and comfortable with using the LMA. She was very surprised to learn that flight programs would be using this device in an out-of-hospital setting. Her explanation was that she thought the movements associated with ventilating these patients in either an aircraft or ambulance would most likely result in a poor seal. I understand that she was referring to the non-intubating style, but just some additional information for you...
