1. Patient Safety & Medical Error
Dr. Nick Sevdalis
Clinical Safety Research Unit, Imperial College
National Patient Safety Agency

2. 1. Some terminology
Adverse event: injury suffered as a result of treatment or hospitalisation
Other terms: iatrogenic injury, critical incident, sentinel event, patient safety incident etc

3. Incidence: the early years
“…the actual mortality in hospitals…is very much higher than the mortality of the same class of diseases treated outside hospitals”
Florence Nightingale

4. Incidence: the last 15 years
Epidemiology of error
Retrospective record reviews
USA (1991): 3.7% of hospital admissions suffered an adverse event
Australia (1999): 16.6%
Denmark (2001): 9%
New Zealand (2002): 12.9%
Canada (2004): 7.5%

5. Incidence: UK Retrospective record review Voluntary reporting system
Vincent et al 2001: 10.8%-11.7%
Voluntary reporting system
National Reporting & Learning System (2005): 4.9%

6. Consequences: the patient Vincent et al. 1994
“While under anaesthetic they apparently cut a blood vessel in my womb, which led to severe haemorrhage … could only be stopped by giving me a hysterectomy so they say”
“A swelling on my cheek was diagnosed as a malignant tumour and part of my jaw and extensive tissue was removed without my consent. The lab. test showed that it was not a tumour, malignant or benign”

7. Consequences: the doctor Christensen 1992
“I was really shaken. My whole feeling of self worth and ability was basically profoundly shaken”
“I was appalled and devastated that I had done this to somebody”

8. Consequences: the NHS Vincent et al 2001
119 adverse events
999 extra bed days
£290,268 extra costs for the Trusts
An Organisation with a Memory 2001
10,000 reported serious adverse drug reactions
NHS pays £400 million in litigation
Hospital acquired infections cost nearly £1billion and 15% are regarded as preventable

9. “The medical establishment has become a major threat to health”
Conclusion
“The medical establishment has become a major threat to health”
Ivan Illich

10. 2. Definition of error Reason 1992
Failure of achieving the intended outcome in a planned sequence of mental or physical activities not attributable to chance
Error
Slip
correct plan, incorrect execution
Mistake
incorrect plan, correct execution
Violation: deliberate deviation from safe rule

11. The person or the system?
The person model
The system model

12. Error in the system (i) James Reason
© J. Reason

13. Error in the system (ii) James Reason
© J. Reason

14. Error in the system (iii) Zhang et al. 2004
Individual
Team
Organisation
National regulations

15. Example: error OF a surgeon…
Patient Risk Factors
Technical skills
Outcome

16. …vs error IN surgery Vincent et al. 2005
Individual skills (motor, cognitive etc.)
Patient Risk Factors
Teamwork & communication
Outcome
Operative environment & procedures
National regulations

17. 3. Surgery Multi-disciplinary team Emergency or elective Process
Surgeon, Anaesthetist, Nurse
ODA, Scrub Nurse, Circulating Nurse
Emergency or elective
Process
Called from ward Put to sleep  operation  recovery  return to ward (discharge)

18. Individual skills: decision-making
Aims:
What does the decision-making process look like?
Can we assess it reliably?
Methods:
Management of patients with symptomatic gallstone disease
Interviews with 10 experienced surgeons
Content-analysed by two reviewers

19. Average = 15.5 decisions/interview
Decision map
Average = 15.5 decisions/interview

20. Cue utilisation
Risk of conversion of a closed (i.e., key-hole) cholecystectomy to an open one
Methods: judgement analysis
Actual risk of conversion
Surgeon
observer
Cues

21. Results (ii) Participant R2 Cues 1 0.758
Previous surgery, Biliary history, Age/co-morbidity 2
0.733
Biliary history, Previous surgery, Obesity 3
0.364 4
0.650
Previous surgery, Biliary history, Obesity 5
0.603
Previous surgery, Biliary history, Race 6
0.388
Biliary history 7
0.613 8
0.501 9
0.434
Previous surgery, Biliary history 10
0.673 11
0.397
Previous surgery, Age/co-morbidity, Obesity 12
0.649

22. Results (iii)

23. Teamwork
Aims: Can we apply a model of surgical teamwork to the surgical team?
Tasks: Equipment, Patient, Communication
Behaviours: Communication, Co-operation, Co-ordination, Leadership, Monitoring/Awareness
Methods
50 general surgery and 50 urology procedures
3 operative stages (pre, intra-, and post-operative)
Task completion rates
Behaviour ratings

24. Results (i) Task Pre-op Op Post-op Surg Urol Equip 56% 61% 82% 91% 89%
95%
Comm
71%
55%
57%
90%
84%
Patient
94%
93%
97%
92%
Overall
69%
77%
80%

25. Results (ii)

26. Operative environment
Physical features
Human element: distractions, interruptions
Aims: Can we observe the distractions/interruptions that occur during a typical procedure?
Methods
50 general surgery procedures
Distraction types
Door openings, auditory, visual, operational

27. Results (i)
Absolute frequency of interference = 663 (13.26/operation)

28. Results (ii)

29. National regulations
27 different crash call numbers in UK hospitals (!)

31. Conclusion: Error in the surgical system
Individual
Team
Organisation
National regulations

32. 4. Conclusions Medical errors occur Medical errors are costly
We are starting to understand their milieu
Physical
Human

33. Future Basic research Interventions
Put some more flesh on the systems view of error
Interdisciplinarity
Funding: medium- to long-term projects
Interventions
Common sense

34. Thank you for your attention!
Questions, comments?