Human Factors Engineering in Healthcare systems:the problem of human error and accident management

Pietro Carlo Cacciabue

EC, Joint Research CentreInstitute for the Protection and Security of the Citizen

Ispra, (VA), Italy

HUMAN FACTORS & MEDICAL INFORMATICS Lille, France, 22 - 24 May 2006

Estimated error risk: USA

• Between 44,000-98,000 patients die as the result of medical errors.

• In 1993, fatalities due to medication errors (7,000) exceeded workplace accidents (6,000).

• Errors by healthcare workers affect approx. 3-4% of patients.

• The cost associated with medical errors is around $29 billion annually.

Comparative rates*

• In US, patient experiences 2 errors a day on average.

• This equates to:– 2 bad landings a day at O’Hare– 32,000 cheques hourly from wrong account

• In US, more people die in horse-drawn vehicles than commercial aircraft.

* British Medical Journal

Annual error risk: UK

• 400 deaths involving medical devices.• 10,000 experiencing adverse drug effects.• 1,150 psychiatric patients commit suicide.• 28,000 written complaints.• £400 million paid out for negligence claims.• Harm occurs in around 10% of admissions.• These cost NHS £2 billion a year in additional

hospital stays.

Is health care unusually fallible? NO

• Patients are more at risk than non-patients.• Medical interventions are, by their nature,

high-risk procedures—small error margins.• Medicine remains an inexact, hands-on

endeavour. Errors are inevitable.• Doctors and patients collude in disguising

the incompleteness of medical knowledge.

But even if . . .

• Healthcare professionals knew all there was to know, they would still make errors.

• Like the rest of human kind, they are fallible.

• But the fact that they are not trained to understand, accept and manage their fallibility lies at the heart of the medical error problem.

Learning to live with error

• Recognise that fallibility is the norm• Errors do not inevitably lead to mishaps• Errors are consequences as well as causes• Naming, blaming and shaming have no

remedial value• Design healthcare systems for real human

beings—warts and all.

Three error types*

• Errors happen when . . .– You know what you’re doing, but the actions

don’t go as planned (slips, lapses, fumbles)– You think you know what you’re doing, but

fail to notice contra-indications, apply a bad ‘rule’ or fail to apply a good ‘rule’ (mistakes and/or violations)

– You’re not really sure what you’re doing (mistakes in novel situations)

* Reason, J. (1997). Managing the risks of organisational accidents. Ashgate, Aldershot, UK.

Two ways of looking at the human contribution

• The PERSON approach: Focuses on the errors and violations of individuals. Remedial efforts directed at people at the ‘sharp end’.

• The SYSTEM approach: Traces the causal factors back into the system as a whole. Remedial efforts directed at situations and organizations.

The ‘Swiss cheese’ modelof accident causation*

Some holes dueto active failures

Other holes due tolatent conditions

(resident ‘pathogens’)Successive layers of defences, barriers, & safeguards

Hazards

Losses

*Ref. J. Reason

Error rates in aviationDerived from observing error rates in 44 flight

hours.

100,000,000+ errors per year

1000 official incident files

100 major incidents

25 accidents

Event rates in surgeryEvents largely due to errors

• Based on direct observation of 165 arterial switch operations: 21 surgeons, 16 centres.

• Average rate: 7 events per procedure– 1 major event (life-threatening)– 6 minor events (disrupts flow, irritates)

• Over half of the major events were successfully compensated: 20% for minors.

• Best compensators get the best outcomes.

A typical major event scenario

Cardiologistmisdiagnoses

coronary arterypattern

Surgeon has not metthis pattern before

Other membersof team are

equallyinexperienced

Surgeon performs aninappropriate procedure

But that is not the end of the story

The surgeon and the team canstill recover the situation

COPINGRESOURCES

Limited coping resourcescan get nibbled away

Accumulation of minor events. Not so much

holes as steadyattrition

Summarising findings• The frequency of events during a procedure

has a profound effect upon outcome.• Compensating major events eliminates any

increased risk of death.• Good compensators have good outcomes• Compensation for minor events is far less

important than their total number.• Minor events erode the coping abilities of

the surgical team.

Managing the manageable

• Fallibility is part of the human condition.

• We are not going to change the human condition.

• But we can change the conditions under which people work.

Engineering Approach to deal with Human Errors

• What is done in other domain• Compare working contexts and techniques• Apply same safety concepts• Need to adapt generic approach to specific

contexts• Data collection, Recurrent Safety Audits• Management with high safety culture

Is it possible that a community of persons• Highly qualified• Motivated• KnowledgeableMake errors that are banal or not explicable

Is it possible• Prevent errors• Recuperate from errors • Mitigate consequences

AviationMedicineNuclearProcess IndustryRail and Road Transport …….

Event

Context and working environment

Human Factors Pathway System Factors Pathway

Defenses, Barriers, Safeguards

Contextual Factors(external)

Casual factors(random)

Active Errors System Failures

Organisational Processes

Latent Errors

Training, Procedures, …… Protection, Emergency, Safety Systems ……

Personal Factors(internal)

Failure of Defenses,Barriers, Safeguards

Generic Framework for

Accident Studies

MEDICINE e AVIATION:Very distant domains, but Many commonalities with respect to human and

organisational issues

Fundamental commonality: Different realties that collaborate to a common objective

Aviation: Cockpit, Maintenance, ATC, Cabin crew, …

Medicine: Operating Theatre (OT), Wards, Laboratories,..

Cabin vs. Operating TheatreOT and Cockpit Similar models of processes and functions Strong safety culture of pilots and surgeons (± safety) Plenty of organisational factorsBuild of different realities

Cockpit Integrated instruments/systemsTransport of persons/goods Small Teams with clear rules

and procedures

OTDifferent instrumentsOne single patient Very complex teams with

discipline/diverse culture

But

Is it possible to prevent human Errors, recover and protect/mitigate consequences

Performance Indicators

Analysis of rules, procedures, needs Ethnographic studies Data collection and analysis

Data

Models

Taxonomies

Collection and Analysis of data about incidents

Incident

Events – HE in Aviation

ASRS :Aviation Safety Reporting System

100,000,000+ errors per year

1000 official incident files

100 major incidents

25 accidents

Events – HE in Medicine

* Workshop on Assembling the Scientific basis for Progress on Patient Safety ( AMA, Chicago, 1998)

Incidents* Errors Discipline Consequences

Florida (amputation) Wrong leg amputation Licence Removed

Betsy Lehman Overdose of Chemotherapy Management removed

Gargano Overdose of Chemotherapy Management removed

Ben Kolb Aesthetic Exchange Police investigation

Libby Zion Exchange of medication Revision of shifts

Einaugler Erroneous injection Doctor arrested

Colorado Exchange of medication Police investigation

* R. L. Helmreich & A. Merri. Culture at work in aviation and medicine. Ashgate, Aldershot, UK (1998).

Errors in OT* Consequences on patient

Lack of communication between surgeon-anaesthesiologist loss of patient

Missing checklist on anaesthesia machine serious problems

Misuse of Oxygen machine serious problems

Surgeon distracted by other operation serious problems

Missed come round of patient ………..

Lack of leadership

Lack of exchange of information on patient characteristics

Conflict of personalities during operation

Inadequate briefing between doctors

………………..

Comparison Medicine - Aviation

In medicine error events seem more frequent than in aviation.

Great variety of involved experts Great number of barriers Errors more frequently identified and

mitigated by system

Six Crucial Requisites for data collection and analysis

Learning

Independence

Interdisciplinary

No blame culture

Minor incidents

Specific analysis

ASRS

Conclusions

Taxonomies

Models

Data

Methods

Active and latent errors

Is it possible that a community of highly qualified, motivated, knowledgeable persons make errors that are banal or not explicable

Is it possible to prevent errors, recuperate from errors and mitigate consequences