The Surgeon and Safety

1. The Surgeon and Safety An Introduction to Safety Theory and Modeling Applications to the OR

2. Overview • Why focus on safety in surgery? • Acknowledge the surgeon as a part of a complex human-machine system, the OR • Why model the OR and the fundamental processes of surgery • Our IDEF model to define surgery and OR activities • Applications • Building the infrastructure for a safer and more efficient OR

3. NY Statistics Preventable Medical Injury • Study population where all hospitalize patients in the NY state during the 1984. • 30,195 randomly selected patients records from all types of acute care hospitals were reviewed by nurse-abstractors using 18 screening criteria for possible “injury” • 7,743 records were reviewed by 2 physicians that were certify either on internal medicine or general surgery. • 1,133 patients were identify as having suffer an adverse event.

4. NY-Patient Injury Findings • 3.7 % of all the discharges were marred by an adverse event • 28% of adverse events were judged as negligence • Over 50% resolved in disability lasting less than a month. • 7% of the disabilities were prolonged of permanent • 14% of the patients died as a result of their injuries • Adverse events were as twice as common in patients over 65 year of age • Vascular, cardiac and neurosurgical patients have a significant higher risk of injury than other type of specialty care

5. NY-Patient Injury Findings • 70% of adverse events were found to be preventable • 24% were judged unpreventable • 6% were classified as potentially preventable

6. Today’s Pre-industrial Medicine • Most other industries have employed systems engineering, safety enhancement programs, and quality control methods. • High risk industries such as aviation are remarkably safe. Airlines typically have four billion flights per major accident (hull-loss) • Would you fly on an airline which crashes four times every one hundred take-offs.

7. Today’s Industrial Age Medicine

8. What is a System • Complex body: a combination of related elements organized into a complex whole • Set of principles: a scheme of ideas or principles, for example, for classification or for forms of government or religion • Way of proceeding: a method or set of procedures for achieving something • Set of interdependent elements interacting to achieve a common aim. These systems may be both human and nonhuman (equipment, technologies, etc).

9. [KF] What is System Modeling? • The process of creating a system model.

10. What is an Engineering Model? • A system model is a formal, symbolic representation of a system in which important system elements, relationships, and behaviors are explicitly represented by structured text, graphical elements and relationships, mathematical equations, or computer software.

11. [KF] What is a System Model? • A formal, symbolic representation of a system in which important system elements, relationships, and behaviors are explicitly represented by structured text, graphical elements and relationships, mathematical equations, or computer software. • A structure that accurately depicts or mimics the real system.

12. [KF] Kinds of System Models • Structural models represent • Systems & subsystems (humans, machines) • Relationships, e.g., • System/subsystem • “Is part of” • Information flow • Communication • Functional models represent • Processes • Functions (goal-directed processes) • Tasks (functions performed by humans) • Procedures (steps to perform functions)

13. Why do we Model? • To understand • To predict • To control • To design • To communicate to our colleagues in the engineering sciences • To realistically train

14. [KF] Why Model? • To understand the system, e.g., • Help engineers understand the basics. • Help medical personnel integrate & get the “big picture”. • To predict, e.g., • What will happen if we change …? • To control, e.g., • How can we speed up turnaround? • To design • Analysis, e.g., • Identify human performance issues & opportunities. • Synthesis, e.g., • Functional specifications for OR automation.

15. What is Surgery? • Medical procedures involving operations: medical treatment that involves operations or manipulations on the patient’s body and, usually, cutting the body open to perform these • Branch of medicine: the branch of medicine that deals with diseases and conditions treated by operation or manipulation, or the range of diseases treated in this way • Surgeon’s art or activity: the art or activity of performing surgery • Operating room: a hospital or clinic room where surgery is performed

16. Surgery Defined as Process • Surgery is a process that physically alters the patient’s anatomy through incision, excision, reconstruction, implantation, etc. in order to diagnosis and treat. • The surgical process transforms the patient’s physiological state to a more advantageous situation (state) for healing, function, cosmesis and the relief of suffering.

17. Surgical Goal Patient Factors Surgical Sys Factors 4 Ps (Philosophy, Policies, Procedures, Practices) Recovering Patient Ready Patient PERFORM SURGERY OR to be Cleaned & Restock OR Ready Surgical Specimens & Waste Documentation Finished Documentation Ready OR Team Surgeon Anesthetist Nursing

18. [KF] IDEF0 • Integrated DEFinition language 0 • Ideal for representing processes & functions • Graphical modeling language • Boxes: functions • Arrows: relationships • Represents any level of abstraction • “Big picture” • Fine details • Depicts concurrency, functional dependencies (not sequences)

19. [KF] IDEF0 Functional Modeling (1) • Function • What is the function or process? • e.g., “perform laparoscopic hysterectomy” • What systems are transformed (changed) by the function? • e.g., patient, the OR, documents • Inputs • What is the state of the systems before the function begins? • Outputs • What is the state of each system after the function is done?

20. [KF] IDEF0 Functional Modeling (2) • Controls • What factors and other things control the function? • Guide it? • Facilitate it? • Impair it? • Mechanisms • What actors (humans, machines) perform it? • Subfunctions • Should this function be described in more detail so as to meet the needs of the analysis? • If so, what are the subfunctions (simpler processes) that must be performed to complete it? • Repeat this process for each of them.

21. IDEF0 Conventions Controls: things that define the goal or/and guide, facilitate, or constrain the function Surgical Goal Patient Factors Surgical Sys Factors Function: a goal directed process 4 Ps (Philosophy, Policies, Procedures, Practices) Recovering Patient Patient Ready PERFORM SURGERY OR to be Cleaned & Restock OR Ready Surgical Specimens & Waste Documentation Finished Documentation Inputs: systems and other things that are changed by the function Outputs: the results of performing the function Ready OR Team Mechanisms: actors (humans or machines) that perform the function

23. [KF] Human performance Issues Analysis • For each primitive function (i.e., those without subfunctions) • Define the systems and subsystems and their interactions. • Identify human performance issues • Physical issues, e.g., • Personnel accommodation • Accessibility of tools, equipment, controls • Sensory issues, e.g., • Visibility • Display design • Cognitive issues, e.g., • Display/control compatibility • Effects of decision biases • Team issues, e.g., • Team situational awareness • Surgeon/-A communication • Identify opportunities for improving human performance. • Changes to equipment • Changes to procedures • Training

24. Our Modeling Team

25. Criticality of failure mode • A procedure in which each potential failure mode is ranked according to the combined influence of severity, detectability, and probability of occurrence.

26. Detectability • The likelihood that detection methods or current process controls will discover and correct a potential failure mode before a patient is harmed.

27. Failure mode and effects analysis A procedure to identify and analyze each potential failure mode in a system to determine • the possible effects on the process • the severity of each potential failure-mode • causes of the failure, and • the actions to be taken to repair the failure

28. Likelihood of error reaching the patient The potential for discovery and correction of an error before it reaches a patient.

29. Failure effect The consequences(s) a failure mode has on the ensuing steps and the ultimate outcome of the process. The effect is described in terms of what the people involved in the process and/or the patient might experience.

30. Failure mode The manner in which a failure is observed; it generally describes the way the failure occurs.

31. Hazard analysis The process of collecting and evaluating information on hazards associated with a process to identify significant risks that require implementation of effective control mechanisms.

32. Probability The assessment of the likelihood that a particular failure mode will happen.

33. Root cause Aspects of the process or environment that are the basic reason for failure or that initiate the problem that eventually leads to the failure, such as • Inadequate procedures • Equipment design defects • Misapplication of information • Lack of knowledge or skills • Wrong methods • Short staffing, or • Ergonomic issues

34. Severity The consequences of a failure as a result of a particular filure mode. Severity considers the worst potential consequence of a failure determined by the degree of patient injury that could ultimately occur.

35. Strategies Actions intended to lower the reisk of failure mode occurrence. If no action is recommended, the decision not to act is noted.

36. FAILURE MODE AND EFFECTS ANALYSIS Prospective risk analysis - involves close examination of high-risk processes to identify needed improvements that will reduce the chance of unintended adverse events.

37. RISK ASSESSMENT PROCESS Used in other industries (ie, aviation and manufacturing) to evaluate system safety. Health care organizations now are using it to evaluate and improve the safety of patient care activities.

38. THE FMEA PROCESS Promotes systematic thinking about the safety of patient care processes ( ie, what could go wrong, what needs to be done to prevent failures.)

41. ACCIDENTS Accidents in the health care setting may be inevitable, but their frequency can be decreased with a dedicated focus on patient safety.

42. RISK REDUCTION Risk reduction naturally flows from a positive approach to risk containment and control.

43. HUMAN ERROR Although it may be human nature to make mistakes, it also is human nature to create solutions, identify alternatives, and meet future challenges.

44. PATIENT SAFETY It is easier for people to do the right thing when a process is made more consistent by standardizing the steps.