Warner KJ, Carlbom D, Cooke CR, et al. Paramedic training for proficient prehospital endotracheal intubation. Preh Emerg Care 14(1): 103-8, Jan-Mar 2010.
Background--Emergency airway management is an important component of resuscitation of critically ill patients. Multiple studies demonstrate variable endotracheal intubation (ETI) success by prehospital providers. Data describing how many ETI training experiences are required to achieve high success rates are sparse. Objectives--To describe the relationship between the number of prehospital ETI experiences and the likelihood of success on subsequent ETI, and to specifically look at uncomplicated first-pass ETI in a university-based training program with substantial resources.
Methods--We conducted a secondary analysis of a prospectively collected cohort of paramedic student prehospital intubation attempts. Data collected on prehospital ETIs included indication, induction agents, number of direct laryngoscopy attempts, and advanced airway procedures performed. We used multivariable generalized estimating equations analysis to determine the effect of cumulative ETI experience on first-pass and overall ETI success rates.
Results--Over a period of three years, 56 paramedic students attempted 576 prehospital ETIs. The odds of overall ETI success were associated with cumulative ETI experience (odds ratio 1.097 per encounter; 95% CI=1.026-1.173; p=0.006). The odds of first-pass ETI success were associated with cumulative ETI experience (OR 1.061 per encounter; 95% CI=1.014-1.109; p=0.009).
Conclusion--In a training program with substantial clinical opportunities and resources, increased ETI success rates were associated with increasing clinical exposure. However, first-pass placement of the ETT with a high success rate requires high numbers of ETI training experiences that may exceed the number available in many training programs.
Few would argue that expertly performed ETI effectively provides an effective and secure airway. However, there is also little doubt that significant patient harm can result from numerous unsuccessful ETI attempts complicated by airway trauma, hypoxia, hypercarbia and aspiration, and in those situations an alternative airway would be a better option. The open question is, what level of proficiency on the part of the intubator, given the unique training and deployment challenges of EMS, is the best for our patients?
There are many questions that affect that decision. One is whether the alternatives are acceptable. The King Airway and laryngeal mask airway are relatively easy to insert and are effective for ventilation and oxygenation. They do not provide the same degree of aspiration protection as an endotracheal tube, but it is not known how important that is. Another is whether there are significant negative consequences to a delayed or unsuccessful ETI. Cardiac arrest studies have indicated that continuous high-quality chest compressions improve outcomes, and that ETI causes prolonged interruptions. Also, long ventilation pauses during rapid sequence intubation increase mortality in brain-injured patents.
So if it's important to be able to do it well, how feasible is it to adequately train paramedics in ETI? The authors here have shown it can be done, but that it took an average of 29 ETIs (20 of them in prehospital patients) to achieve an 80% first-pass success and 95% overall success rate. This is consistent with a previous study that found it took 20-25 ETIs to achieve a 90% success rate (Wang, Preh Emerg Care 9:156, 2005). It is also in line with training standards for physicians, who are required to perform 35-60 ETIs in emergency medicine and anesthesia. In fact, with optimal training and high frequency of skills use, paramedics and physicians in the same air ambulance service have been shown to have identical 97% success rates (Fullerton, Resusc 80:1,342, Dec 2009).
We should be looking at this from the perspective of how to provide the safest and best medical care for our patients. It may be that what we now accept as adequate training and ongoing experience is not sufficient. EMS systems should consider this in their training, scopes of practice, treatment protocols and QI programs.
Angelo Salvucci, Jr., MD, FACEP, is an emergency physician and medical director for the Santa Barbara County and Ventura County (CA) EMS agencies.