Instructors and graduates of certain Life Support courses will be familiar with the ‘four stage’ approach to teaching procedural skills (demonstration, deconstruction, formulation, performance):
Silent run through in which teacher performs without commentary;
teacher then performs while commentating;
teacher then performs with commentary from student(s);
finally student performs and commentates.
Two randomised studies published this month showed no improvement in skills performance with this teaching method compared with simpler approaches. One involved needle cricothyroidotomy1 and another laryngeal mask insertion2.
An accompanying editorial3 acknowledges that this might put an end to this educational dogma, but one should consider that the procedures taught in these studies were simple to perform, and the results might not be extendable to more complex procedures. The editorial points out there are some interesting data describing the neurophysiological basis of learning. Observing actions made by others activates the cortical circuits responsible for the planning and execution of those same actions; this visual-motor coupling happens through a neuronal matching network called the Mirror Neuron System (MNS). Listening to a verbal description of a skill can activate the same visual-motor circuit as those activated by the hand or the leg when completing the skill. Even during new motor pattern formation there is significant NMS activation, supporting the concept that the building of motor memories is based on the combination of observation and execution.
The ingredients of the complex mechanism of motor learning are observation, listening and immediate execution. The priority that should be given to each of the individual components of motor skills teaching is difficult to quantify and should be the subject of future research.
The editorialists conclude: The four-stage approach has been used for years with no evidence of better skill acquisition and retention compared with traditional methods. Medical educators need high-quality data to address the knowledge gaps for this topic and the two studies in this issue have set a precedent for future research. In our opinion, we should continue to use the four-stage approach to skill teaching while waiting for more evidence of a superior approach.
I differ slightly in my conclusion: if I have a limited time to teach a skill station (like airway management in the APLS course), I know I’m a little more justified in ditching this time consuming ritual in favour of more hands-on time for the paying delegates.
1. Emergency skill training—A randomized controlled study on the effectiveness of the 4-stage approach compared to traditional clinical teaching Resuscitation. 2010 Dec;81(12):1692-7
2. A randomised trial comparing a 4-stage to 2-stage teaching technique for laryngeal mask insertion Resuscitation. 2010 Dec;81(12):1687-91
3. The four-stage approach to teaching skills: The end of a dogma? Resuscitation. 2010 Dec;81(12):1607-8
Neurologist Vilayanur Ramachandran explains the mirror neuron system in this video from TED.com:
This aim of the study was to evaluate the tracheal intubation success rate of doctors drawn from different clinical specialities performing rapid sequence intubation (RSI) in the pre-hospital environment operating on the Warwickshire and Northamptonshire Air Ambulance. Over a 5-year period, RSI was performed in 200 cases (3.1/month).
Failure to intubate was declared if >2 successive attempts were required to achieve intubation or an ETT could not be placed correctly necessitating the use of an alternate airway. Successful intubation occurred in 194 cases, giving a failure rate of 3% (6 cases, 95% CI 0.6 to 5.3%). While no difference in failure rate was observed between emergency department (ED) staff and anaesthetists (2.73% (3/110, 95% CI 0 to 5.7%) vs 0% (0/55, 95% CI 0 to 0%); p=0.55), a significant difference was found when non-ED, non- anaesthetic staff (GP and surgical) were compared to anaesthetists (10.34% (3/29, 95% CI 0 to 21.4%) vs 0%; p=0.04). There was no significant difference associated with seniority of practitioner (p=0.65). The authors conclude that non-anaesthetic practitioners have a higher tracheal intubation failure rate during pre-hospital RSI, which may reflect a lack of training opportunities.
The small numbers of ‘failure’ rates, combined with the definition of failure in this study, make it hard to draw generalisations. Of note is that the paper lists the outcomes of the six patients who met the failed intubation definition, all of whom appear to have had their airway satisfactorily maintained by the RSI practitioner, three by eventual tracheal intubation, one by LMA, and two by surgical airway. More data are needed before whole specialties are judged on the performance of a small group of doctors. Should non-anaesthetists perform pre-hospital rapid sequence induction? an observational study Emerg Med J. 2010 Jul 26. [Epub ahead of print]
A single centre observational study of rapid sequence intubation (RSI) was performed in a Scottish Emergency Department (ED) over four and a quarter years, followed by a postal survey of ED RSI operators.
There were 329 RSIs during the study period. RSI was performed by emergency physicians (both trained specialists and training grade, or ‘registrar’ doctors) in 288 (88%) patients. Complication rates were low and there were only two failed intubations requiring surgical airways (0.6%). ED registrars were the predominant RSI operator, with 206 patients (63%). ED consultants performed RSIs on 82 (25%) patients, anaesthetic registrars on 31 (9.4%) patients, and anaesthetic consultants on 8 (2.4%) patients. An ED consultant was present during every RSI performed and an anaesthetist was present during 72 (22%). The average number of ED registrars during this period of training was 8. This equates to each ED trainee performing approximately 26 ED RSIs (6.5 RSIs/year). On average, ED consultants performed 14 RSIs during this period (approx 3.5 RSIs/year). Of the 17 questionnaires, 12 were completed, in all of which cases the trainees were confident to perform RSI independently at the end of registrar training. Interestingly, 45 (14%) of the RSIs in the study were done in the pre-hospital environment by ED staff, two thirds of which were done by ED consultants. Training and competency in rapid sequence intubation: the perspective from a Scottish teaching hospital emergency department Emerg Med J. 2010 Sep 15. [Epub ahead of print]
More junior pre-hospital doctors took longer on scene than their senior colleagues according to a German study, although patient clinical factors were the main determinant of scene time. The majority of cases were non-trauma presentations Duration of mission time in prehospital emergency medicine: effects of emergency severity and physicians level of education Emerg Med J 2010;27:398-403
Hospitals and medical personnel performing high volumes of procedures demonstrate better patient outcomes and fewer adverse events. The relationship between rescuer experience and patient survival for out-of-hospital endotracheal intubation is unknown.
An American study analysing 3 statewide databases with 26,000 records aimed to determine the association between endotracheal intubation experience and patient survival.
In-the-field intubators were EMS paramedics, nurses, and physicians, although paramedics performed more than 94% of out-of-hospital tracheal intubations. Although all air medical rescuers may use neuromuscular- blockade-assisted (rapid sequence) tracheal intubation, select ground EMS units are allowed to use tracheal intubation facilitated by sedatives only; the rest are done ‘cold’.
Patients in cardiac arrest and medical nonarrest experienced increased odds of survival when intubated by rescuers with high procedural experience. In trauma patients, survival was not associated with rescuer experience.
The odds of survival for air medical trauma patients were almost twice that of other patients, which may be related to the use of neuromuscular- blocking agents by air medical crews, or due to more specialised critical care training. The authors suggest that rescuers should perform at least 4 to 12 annual tracheal intubations. Out-of-Hospital Endotracheal Intubation Experience and Patient Outcomes Ann Emerg Med. 2010 Jun;55(6):527-537
Medical students and junior doctors were successfully taught correct airway management positioning for intubation on a manikin when told to position the manikin in the best position to win a running race, where the chin wins the race. (The so-called ‘win with the chin’ position). This was superior to the traditional ‘sniff the morning air’ position. "Intubate Meee!!" Teaching airway management to novices: a simulator manikin study comparing the ‘sniffing position’ and ‘win with the chin’ analogies Br J Anaesth. 2010 Apr;104(4):496-500
During simulated cardiac arrest resuscitations, a comparision was made between those run by teams that had had time to form before the arrest, and those that had to be assembled ad hoc after the arrest occurred. 99 teams of three doctors, including GPs and hospital physicians were studied. ACLS algorithms were less closely followed in the ad hoc formed teams, with more delays to therapies such as defibrillation. Analysis of voice recordings revealed the ad hoc teams to make fewer leadership utterances (eg. ‘we should defibrillate’ or ‘the next countershock will be 360J’) and more reflective utterances (eg. ‘what should we do next?’). The authors suggest that team building is therefore to be regarded as an additional task imposed on teams formed ad hoc during CPR that may substantially impact on outcome. No surprise to those of us who banned ‘cardiac arrest teams’ from our emergency department resuscitation rooms many years ago!
The editorial points out there are some interesting data describing the neurophysiological basis of learning. Observing actions made by others activates the cortical circuits responsible for the planning and execution of those same actions; this visual-motor coupling happens through a neuronal matching network called the Mirror Neuron System (MNS). Listening to a verbal description of a skill can activate the same visual-motor circuit as those activated by the hand or the leg when completing the skill. Even during new motor pattern formation there is significant NMS activation, supporting the concept that the building of motor memories is based on the combination of observation and execution.
