he emergency medical service (EMS) as we know it today evolved from the fertile minds of two great anesthesiologists, Eugene Nagel, M.D., and Peter Safar, M.D. (1924-2003).^1,2 Their inspirations arose separately and independently, but almost simultaneously, in the mid-1960s. Dr. Nagel worked at the University of Maryland, Baltimore, and Dr. Safar at the University of Pittsburgh. Both men were scholars and teachers of the newly discovered art and science of cardiopulmonary resuscitation, or CPR. They realized that in order to maximally benefit the public, the skills involved in artificial respiration and closed chest cardiac compression must be made available outside of the hospital. The brief interval between hypoxia and cerebral damage did not permit a passive transport through traffic to the hospital. Both began to train paramedics to do mouth-to-mouth and bag-and-mask ventilation and closed-chest cardiac massage. Both appealed to ASA for help to establish their paramedic system nationwide.

Their timing was excellent. The nation’s ambulance system, which was operated by private funeral homes, was riddled in scandal. Some were very good, with conscientious drivers trained in first-aid who had good assistants. Others were disasters arriving at the scene of an accident, preferring to pick up the dead rather than the wounded because they were more likely to be paid. With the backing of ASA and the addition of the 9-1-1 system, the EMS spread rapidly across the nation. Paramedics are now trained in more than 250 community colleges in programs that are accredited, and graduates must pass a state or national registry examination. Operating room training in airway management under supervision of an anesthesiologist or nurse anesthetist is required and should include jaw lift, head tilt, airway clearing maneuvers, oral and nasal airways, bag-and-mask ventilation and endotracheal intubation. Endotracheal intubation is taught as the “gold standard” of airway care in the unconscious patient. The famous trauma surgeon, F.W. Blaisdell, M.D., said in 1985, “Airway maintenance and ventilation by an endotracheal tube constitute magic.”³ The magic would not last. A crisis emerged in 1999.

Progressively, anesthesiologists in community hospitals across the country withdrew from teaching airway management to paramedics in the operating room. The reasons given were fear of liability, advice of an insurance carrier, problems of informed consent and the growing frequency of the use of laryngeal mask airway (LMA) in routine practice. The crisis occurred as paramedic training programs could not find enough supervised experience in operating rooms to meet the standards for accreditation. The ASA Committee on Critical Care Medicine and Trauma Medicine came to the rescue.

Under the leadership of Gerald A. Maccioli, M.D., the following resolution passed the 2004 House of Delegates and became ASA policy:

“Resolved, that ASA encourage its members and other qualified providers to offer supervised operating room experience or simulation in airway management, including endotracheal intubation, and be it further resolved that the ASA develop suggestions for patient’s informed consent in connection with such training and work with insurers to lessen the liability concerns for its members who engage in supervised training of paramedics, and be it further resolved that ASA encourage the Foundation for Anesthesia Education and Research and the Anesthesia Patient Safety Foundation to foster research on the use of LMA and other methods of airway management as effective alternatives to endotracheal intubation in emergency services.”

Having received the support of their national Society, many anesthesiologists in small community hospitals have resumed training paramedics. The crisis of training has eased a bit, but now the efficacy of endotracheal intubation in prehospital care is being questioned. Is it indeed the “gold standard?”

Anesthesiologists have assumed that endotracheal intubation would improve oxygenation and improve outcome. Recent studies have cast doubt on that assumption. A prospective series of 830 pediatric patients (< 12 years of age) who required airway management as part of prehospital care were randomized into two groups, one of which received bag-and-mask ventilation and the second endotracheal intubation.⁴ No difference was found in the survival or neurological outcome between the two groups. In other words, prehospital endotracheal intubation did not produce the expected improvement in outcome.

The study generated extensive debate and additional studies in adults. Brochiccio et al. reported a prospective study of 191 patients. Seventy-eight were intubated in the field, and 113 were intubated immediately after admission to the emergency room.⁵ The authors found that prehospital intubation is associated with a significant increase in morbidity and mortality in traumatized patients with traumatic brain injury. The problem may not be the intubation itself but rather the tendency of paramedics to hyperventilate after the intubation is successful.⁶

We believe that anesthesiologists should continue to be involved in the training of airway management, recognizing that certain problems exist when that training is offered. This training should include chin lift, jaw thrust, airway clearing maneuvers, oral and nasal airways, bag-and-mask ventilation and endotracheal intubation. We believe that the time has come to study the validity of the “gold standard” assumption and to evaluate the efficacy of alternative techniques of prehospital airway management such as ProSeal™ LMA or Combitube™. Anesthesiologists should be the leaders in this research.


References:
1. Safar PJ. On the history of emergency medical services. Bull Anesth History. 2001; 19:1,2-8.
2. Nagel E. History of emergency medicine: A memoir. Bull Anesth History. 2001; 19:1,9-10.
3. Blaisdell FW. 1984 Fitts lecture, trauma myths and magic. J Trauma. 1985; 25: 856-863.
4. Gausche M, Lewis RJ, Stratton SJ, et al. Effect of out of hospital pediatric endotracheal intubation on survival and neurological outcome, a controlled clinical trial. JAMA. 2000; 283:783-790.
5. Bochicchio GV, Ilahi, O, Manjari J, Bochicchio K, Scalea TM. Endotracheal intubation in the field does not improve outcome in trauma patients who present without an acutely lethal traumatic brain injury. J Trauma. 2003; 54:307-311.
6. Shafi S, Gentilello LM. Prehospital endotracheal intubation and positive pressure ventilation are associated with hypotension and decreased survival in hypovolemic trauma patients, an analysis of the National Trauma Data Bank. J Trauma. 2004; 57:488.

Adolph H. Giesecke, M.D., is Emeritus Professor, University of Texas Southwestern Medical Center, Dallas, Texas. He is Past President of International TraumaCare.

William H. Montgomery, M.D., is Associate Professor of Anesthesiology, Straub Clinic and Hospital, Honolulu, Hawaii.