Wednesday 21 May 2014

It's all human error

Over the past 12 months, human error has been responsible for:


The term "human error" has become a catch-all for a smorgasbord of occurrences such as unintelligible hand-writing, fatigue, double-counting, pressure to under-report, etc. However, the commonality of these news reports is that there was a human at the sharp end and a suggestion that "human error" is the counterpart of "technical error" or "equipment failure".

One of the problems with using the term "human error" is that "equipment failure" is often also "human error" separated by space and time. For example, if an engine fails on an aircraft (a technical error) then one could trace this failure back to poor engine design or manufacture or installation or maintenance, all of which are "human error". Seen in this light the only true non-human causes of accidents are "acts of God" such as earthquakes or tsunamis. (Even with the latter, the (human) decision to lower the Fukushima nuclear plant from 35m to 10m above sea level contributed to this post-tsunami disaster.) Technical or equipment errors are also strongly implicated in many human errors.

Thiopentone and Co-amoxiclav (or perhaps the other way 'round?)
For example, drug manufacturers are at liberty to package their drugs in whatever vial colour and design they choose. This leads to an increase in the number of people getting the wrong drug. New medical devices (pumps, anaesthetic machines, defibrillators, monitors) are not stress-tested in conditions where error is likely. These design errors lead to human error.

Death knell for "human error"?

Does the term "human error" serve a purpose? At a very coarse level it may tell us if there was a human at the sharp end, but other than that it suggests an unwillingness to delve deeper into the accident. It also implies that if we could get rid of the "human", by increased automation for example, systems would be safer. The term "human error" should therefore be replaced, not by one new term but by the correct (as far as is known at the time) term(s) which best explain the accident causation. This may be performance variability and/or organisational variability and/or equipment design...

Further reading

A very well-written post on human error by Steven Shorrock at safetydifferently.com:  "The use and abuse of ‘human error’"

Monday 12 May 2014

Book of the Month: Practical Health Care Simulations (Loyd, Lake, Greenberg (eds))

About the editors


At the time of publication (2004), Gary Loyd was Clinical Director of the Simulations Centre, Carol Lake was Professor of Anaesthesia and Ruth Greenberg was Director for Health Sciences Centre Academic Programmes, all at the University of Louisville School of Medicine.

About the contributors

There are 50 contributors listed (including the three editors), 13 of whom were based at the University of Louisville. There are 7 non-US contributors (the 3 European contributors are easy to spot as they aren't given first names):
  • Canada: Brigitte Bonin & Glenn Posner (Ottawa), Susan DeSousa & Pamela Morgan (Toronto)
  • The Netherlands: J. J. M. C. H. de la Rosette & M. P. Laguna (Amsterdam)
  • Greece: D. N. Mitropoulos (Athens)

Who should read this book?

The editors' intended readership is the "new or soon-to-be simulation educator". Unfortunately, at 613 pages, this is probably wishful thinking. No-one should read the entire book but some parts are worth dipping into (see below). 

In summary

The book is split into 3 sections:
  1. The Basics: 5 chapters looking at the history of medical simulation, the current status of simulation in education and research, planning a simulation centre (space, personnel, business)
  2. Practical Applications: 23 chapters ranging from "simulation in pharmacology" to "use of simulation in legal services"
  3. The Future: 1 chapter on "What's next in simulation"
Some parts are better than others (see below).

What's good about this book?

Although Chapter 2, "Current Status of Simulation in Education and Research", ran the risk of being out-of-date by the time the book was published the conclusion still holds true: 
"The theoretical benefits of (simulation) over live-patient training… warrants serious, well-designed, objective investigation…"
Chapter 3 "Space considerations in health care simulation" is useful for those who are designing a new simulation centre. Over 25 pages it discusses not just the space requirements but also provides practical advice about group size, financial support, flow pattern and layout.

Chapter 4 "Human considerations in health care simulation" provides the job descriptions, expected time commitment and qualifications of simulation centre personnel which should consist of:

  • Simulation Center Coordinator/Manager
  • Secretary/Receptionist
  • Educational Consultant
  • Research Director
  • Research Associate
  • Faculty Facilitators
  • Actors, Role Players
Of course most simulation centres can only dream about having this many personnel (and simulation technicians seem to have been missed out).

Chapter 5 "Strategic and Business Planning for a Human Patient Simulator Center" gives an insight into the difficulties of financing a sim centre. The "Year One Budget" (p.112) example shows a revenue of $1,362,250. $312,250 (23%) of this is from course income, the remainder is from endowments, dean's office support, a $500,000 gift and a $350,000 loan. This may be useful ammunition when discussing the profitability of your simulation centre.

The book provides ideas to increase the number and type of courses including teaching physiology and pharmacology, as well as increasing the number of participants by bringing some into the control room and streaming the scenario to a lecture theatre. There are also suggestions of different types of simulation activities such as "faculty available" where the participants carry out assignments without faculty (who can be called if needed) and "open laboratory" where participants work unsupervised. 

What's bad about this book?

The book starts off badly with "The History of Medical Simulation" which is really a history of resuscitation, poorly written and sprinkled with spelling mistakes. It also includes dates such as "1946 - Mendelson syndrome report" "1947 - Guriech and Yuniev… showed that DC charge was more effective than AC for resuscitation…" The "noise" generated by the trivial drowns out the "signal" of important simulation milestones. The author of this chapter also states: "The optimal duration for a simulation training session is 75-90 minutes" and it is unclear whether this means total duration or duration of, for example, a scenario.

Many chapters start off with with the same "basics" of simulation which would have been best covered in a single chapter. In addition, somewhat bizarrely "Simulation in Life Support Protocols" (chapter 17) sits between "Simulation in Urologic Surgery" and "Simulation in Obstetrics and Gynecology".

Chapter 8, "Simulation in Physical Diagnosis", can be skipped as it consists almost entirely of useless tables such as Table 7: Internet Links to Miscellaneous Simulators.

Lastly, the editors must bear some responsibility for the lack of cohesion and poor organisation. They attempt to excuse this (and perhaps forewarn the reader) in the preface:
"The format is diverse, reflecting the diverse paradigms from which different health care workers approach their work with simulation."
However the fact that, for example, the chapter on simulation in paediatrics is only 5 pages long suggests that some of the authors may have been selected for their proximity (physical or social) to the editors rather than expertise.


Final thoughts

This 613-page tome will certainly look good on the shelf. It may also be useful to have a quick read-through of one of the chapters relating to a given specialty if you're thinking about starting a new course. Some of the chapters are worth reading including "Simulation in Crisis Management" and "Simulation in Emergency Medicine" which provides a 3-year EM simulation curriculum. However, this book is now 10 years old and the effort required to find the gems amongst the mundane is considerable.