Diastolic Learning: Making the Tacit, Explicit

Background

Surgery is a motor skill that has to be learnt through practice. The acquisition of motor skills and the principles are well documented especially in sport. The theory and practice of coaching all athletes at every level involves an understanding of the fundamentals of movement and ergonomics. In the current era, surgical training has evolved in order to conform with certain conditions: The European Working Time Directive (shorter workweek for residents), increasing complexity of cases and emphasis on operating room efficiency as well as mitigating medical error constitute limitations in the preparation of trainees for the operating room experience. Simulation techniques are based on established theories on motor skill acquisition and development of expertise [1]. Fitts and Posner’s three-stage theory is widely accepted [2]. Many consultants of today learnt their skills by volume, by ‘practicing’ on patients. Basic Surgical Skills were acquired and rarely taught. Many a trainer, when asked how they executed a specific task will not be able to deconstruct the actions into set up, posture, instrument handling, angles etc. They will when it is explained i.e. the tacit is made explicit. The handling of instruments and the passage of the needle through the tissue can be explained in a similar way – this theory has been published and the success of this teaching is realised over sixteen years delivering critically acclaimed courses – PAR Excellence and PAR Aorta courses. The feedback from trainees includes “I wish I was taught this earlier!” and “why hasn’t anyone explained this to me before!” Most models suggest that the earlier stages should take place outside the operating room. Fidelity may be less important at relatively junior levels of training. Initial acquisition of skills require block practice i.e. repetition. This can be done at home on low fidelity models that offer visible and tactile feedback [3]. Deliberate practice is the engagement in structured activities created specifically to improve performance in a domain and requires feedback. Are experts ‘born’ or ‘made’? This is a highly controversial issue. The 10 000 hours needed to become an expert can be helped in the early stages of training with deliberate practice and observation by a skilled trainer. The aim of this project is to establish whether a combination of low fidelity simulation models and deliberate practice can reliably predict achievement of basic surgical skills competency. The tasks were recorded and videos were reviewed and scored by the assessors.

Results

Twenty eight out of thirty participants demonstrated improvement in all four variables. On average the time needed to complete the task on first attempt was 4:46 mins (range 3:41 – 5:30mins) and on second attempt 3:24 mins (range 2:00 – 4:00mins). The improvement in task completion time was 28.6%. The flow / rhythm parameter was improved 40% and this is obvious on watching attempts 1 and 2 of each participant. There is a clear difference in the needle handling, pick-up and delivery. This improvement can be described as more deliberate and planned movements with significant reduction of hesitation, deviation, interruption and repetition.

Discussion

The practice of surgery like all sports requires the application of the same principles. It is important to deconstruct the movements and explain ergonomics required to achieve the action. It is this understanding and rehearsal of these movements that will cultivate and reinforce a motor memory resulting in a reduction in the diastolic time of an operation and a smooth transition between actions. These simple principles have been employed in the instruction of the martial arts for thousands of years. The power and flow is achieved with an attention to the practice of the deconstructed movements; the first skill is to master correctness. Most skills workshops have trainees seated (picture here) on fixed chairs operating at tables – this is not optimising the functional anatomy of the upper limb and cannot be further from the movements and understanding of the ergonomics required to effect a smooth action at the operating table where we are standing. Those disciplines that do sit to operate undoubtedly have a stool that is on wheels and goes up and down. The stool can move through three dimensions. It is not fixed. We are training our surgeons incorrectly. Moreover, we do not offer a framework of understanding or provide models for deliberate practice. There is a very attractive meritocratic and egalitarian attribute to Ericsson’s view that everyone can attain expert level of performance with enough hard work, coaching and feedback. Antagonists have commented that the deliberate practice theory requires ‘a blindness to ordinary experience’ and to the fact that most people who want to become experts – in music, sports or other domains- do not make it [4]. Furthermore, literature provides support for Ericson’s contention that many professionals probably never attain true expertise [1]. A recent meta-analysis concluded that the volume of deliberate practice – although unquestionably important as a predictor of individual differences in performance - is not as important as Ericsson and colleagues have argued. In fact it could only explain up to thirty percent of the variance [5]. Currently, two types of operative skills assessment are in use: Rating scales and motion analysis. In this work we used rating scales as despite our research we were not able to identify the software required for reliable video interpretation and scoring. However, there are no defined relevant, robust measures of outcome that can be directly attributed to the effects of training. Therefore correlating assessment with future performance is difficult. Furthermore, as reliability and validity of assessment tools is increasing it is likely that competence-based advancement, rather than time served, will become standard in surgical training [1]. William Halsted, when he introduced the residency training system which remains the cornerstone of surgical training more than a century later, also supported competence-based advancement.

Limitations

In our opinion this project (supported by our experience with the PAR courses over last ten years) provides compelling evidence that basic surgical skills can reliably be taught and learned using low fidelity models and deliberate practice.

Three of the parameters measured (flow/rhythm, precision and rotation) are qualitative and subjective by definition. However, time/pace, which was the only objectively quantifiable parameter, showed an impressive 30% improvement. Furthermore participants reported their average practice times but they were not directly observed. In our experience character traits such as persistence and motivation play a role on how much time a trainee spends practicing and this has direct implications on their ability to perform the task.

Conclusion

This project has enhanced our knowledge and practice in surgical education and training both from trainee and trainer perspectives. Our work provides evidence on how low-fidelity simulation models can reliably be used to achieve significant progress through early stages of the learning curve. Furthermore it demonstrates the principles that need to be observed in order for deliberate practice to be effective and efficient in acquisition of surgical skills. Accurate assessment of an individual’s abilities at an early stage may be critical in their choice of career and whether they have a realistic chance of becoming an expert through deliberate practice. The usefulness of any particular assessment method is determined by its reliability, validity, impact on future learning and practice, acceptability to learners-faculty, and costs [6].

The next step in this project is to use video based motion analysis in order to objectively quantify the measured parameters. Our aim is to provide insight into how assessment methods can be optimized in terms of validity, reproducibility and cost-efficiency.