1 / 54

Clinical Engineering Why do hospitals need engineers?

Clinical Engineering Engineers in the Modern Academic Medical Center Design Disasters Consequences of Blunders, Bad Luck, and Bias. Patrick Norris, Ph.D. Assistant Professor of Surgery, Biomedical Engineering patrick.norris@vanderbilt.edu. Clinical Engineering Why do hospitals need engineers?.

luyu
Download Presentation

Clinical Engineering Why do hospitals need engineers?

An Image/Link below is provided (as is) to download presentation Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author. Content is provided to you AS IS for your information and personal use only. Download presentation by click this link. While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server. During download, if you can't get a presentation, the file might be deleted by the publisher.

E N D

Presentation Transcript

  1. Clinical EngineeringEngineers in the Modern Academic Medical CenterDesign DisastersConsequences of Blunders, Bad Luck, and Bias Patrick Norris, Ph.D.Assistant Professor of Surgery,Biomedical Engineeringpatrick.norris@vanderbilt.edu

  2. Clinical EngineeringWhy do hospitals need engineers? • Definition • Past, Present, Future • Examples • Facility Design • Biomedical Devices • Information and Technology Management • Clinical Research, Quality Improvement

  3. Biomedical Electronics Definition Clinical Technology Service Biomedical Engineering

  4. DefinitionThe American College of Clinical Engineering: A professional who supports and advances patient care by applying engineering and management skills to healthcare technology.

  5. Definition:Hospitals need engineers when technology requires: • Special (non-trade/craft skills) customization or maintenance • Complex selection criteria • Modification of existing facilities or systems, or special design of new ones • Design and analytic skills, professional credentials, etc. differentiate engineers from technicians, craftspeople, clerical, administrators, etc…

  6. Examples: Past • Einthoven: EKG, early 1900’s • Other examples: • Day to day heat, AC, water, electricity, etc.

  7. Examples: Present • Infrastructure Design • Typical: Water, Electrical, HVAC, Telecom • Special: Medical Gas, Sample Handling • Structural: Imaging Systems • Biomedical Devices • Selection, integration, tracking • Maintenance is becoming a sophisticated trade/craft skill • Information

  8. Future • Information • Medical Informatics • 6 VUSE PhDs • Integration • People • IT Systems • Medical Devices • Regulation • Privacy, Safety, Efficacy • Across Multiple Healthcare Systems Grimes SL, IEEE Engineering in Medicine and Biology Magazine, March/April 2003 p.91-99

  9. Clinical Research • SIMON Project • (Signal Interpretation and Monitoring) • Ongoing since 1994 • Seeks to Advance: • Medical Monitoring Technology • Critical Care • Scientific Knowledge • Clinical Engineering Component

  10. Trauma • 5th Leading Cause of Death (1st Under 45) • 8% of Medical Expenditures (rank: 3rd) • All Age and Socioeconomic Groups • VUMC • Only Level 1 Facility, 65,000 Square Miles • 3500 Annual Admissions • 800 to Trauma ICU, ~10% Mortality

  11. Cushing, early 1900’s: Importance of Monitoring and Recording Vital Signs Technology Has Advanced Fundamentally, Clinical Strategies Remain Unchanged Intermittent Recording Manual Interpretation Patient Monitoring

  12. Tools for Dense Physiologic Data Management

  13. Four Engineering Challenges • Data Collection • Interfaces to a Variety of Devices • Remote Locations • Storage • Clinical Applications - Short-Term • Research Applications - “Forever” • Processing • Time-Critical Tasks (Clinical Decision Support) • Research Analysis • Architecture • Integration, Reliability, Scalability, Flexibility…

  14. SIMON Data Capture • Philips CareVue • Routine, Automatic Vital Signs Capture • HR, ABP, PAP, CVP, ICP, CPP, PAP, SaO2 • Episodic Waveform Capture • Edwards Vigilance • CI, EDVI, temp, SvO2, etc. • Alaris IV Pump (near future?)

  15. SIMON Data Storage • Relational Database • Time Constraints w/ Limited Resources • Adaptive Sampling, ~0.25-1Hz Storage • 5500+ TICU Patients • Reliably Identified, Linked to Outcomes • 450,000+ Continuous Hours • Grows by: • 2 Million+ Data Points/Day • ~70 Patients/Month

  16. Daily Reports

  17. Data Display

  18. Effective Alerting Right Information Right Person Right Time Process Event Alert Notification Response Alerts

  19. SIMON Architecture • Modular, Simple Components • Scalable • Reliable • Flexible • Time-Constrained

  20. Data Collector ODBC Data Collection Modules (1 per device) SQL 2k System Mgr. Bed 1 Database Mgr. Bed 2 Event Engine SIMONW1 (Secure WWW Server)trauma.mc.vanderbilt.edu Bed 3 Alert Engine Notify Engine Simon Packet Format • Census Agent Census Monitor sFTP • VUMC Census • Bed 14 Report Engine sFTP VUMC StarPanel SIMONT1 SIMONS1 Devices Digi Driver

  21. Research Hypotheses New measurements, available through techniques of dense data capture and analysis, will: • Identify failure of communication pathways (uncoupling) • Linking systems, organs, cells, proteins, and genes • Illuminate underlying control mechanisms • …especially in the critically ill

  22. 1.5 N = 825 1.0 Percent Time, entire stay 0.5 0 0 0.5 1.0 1.5 2.0 2.5 3.0 3.5 5-minute HR Standard Deviation Short-Term HRV - Survival

  23. 1.5 N = 98 1.0 Percent Time, entire stay 0.5 0 0 0.5 1.0 1.5 2.0 2.5 3.0 3.5 5-minute HR Standard Deviation Short-Term HRV - Death

  24. 1.5 N = 923 1.0 Percent Time, entire stay 0.5 0 0 0.5 1.0 1.5 2.0 2.5 3.0 3.5 5-minute HR Standard Deviation Short-Term HRV - Combined Time normalizedwithin outcome group

  25. Design DisastersConsequences of Blunders, Bad Luck & Bias • What is a Design Failure? • Why Do They Happen? • Examples • “Recipes for Design Disasters” • Space Program • Transportation • Medical

  26. What is a Design Failure? • Elements of Establishing Defect: • Identify the design defect • Establish a causal link to harm or cost • Identify alternate designs (correctable) • Compare to similar products • “A product does not have a design defect when it is safe for any reasonably foreseeable use and meets all applicable functional specifications.” Geddes, Medical Device Accidents With Illustrative Cases

  27. Example Design Defect(probably from urban legend) Nurses in Pelonomi Hospital, South African hospital were baffled that every Friday morning the patient in one particular bed would be found dead! Investigation revealed that the cleaning person would unplug that bed’s life support equipment, in order to plug in her floor polisher when she did the floors each Friday. When finished, she would plug the equipment back in unaware that the patient was now dead.

  28. Example Design Defect Definition Pelonomi Hospital Legend Life support equipment could be unknowingly unplugged Staff were not alerted when machine unplugged, patient died Alarms and batteries All life-critical equipment offered by vendors X,Y,Z have alarm & battery backup • Identify defect • Causal link • Alternate designs • Comparison

  29. What is a Design Failure? • There are plenty of definitions • Numerous example cases • In the end, failures are debatable • Ultimately, court may have to decide • With testimony from experts • Sometimes difficult to separate liability from design flaw • Negligence is a legal, not technical, term

  30. Why Do Designs Fail?At least three types of factors • Blunders (Human Error) • “Everyone makes mistakes” • Bad Luck (Random Effects) • “S*** happens” • Bias • People sometimes believe what they want to, irrespective of facts • Especially when money, power, relationships are involved

  31. Example: $125M Blunder • 1999 Mars Orbiter • JPL, Lockheed • Metric vs. English units • Erroneous orbital entry calculation – engine burn time

  32. Example: Bad Luck (?) • Weather: A random effect • Dense fog on I-75 • 99 vehicle pile-up in TN • Killing 12, injuring 56 • Initially weather blamed • Then local paper mill • $13.5M settlement • Once = bad luck • Many times = negligence?

  33. Example: Bad Luck • Tacoma-Narrows bridge • Unforeseeable consequence of lightweight design, wind profile • No human deaths • $5.2M in 1940, ~$70M today • (Insurance paid)

  34. Types of Bias • “Statistical” • Sampling • Multiple comparisons • Repeated measurements • Psycho-Social • Groupthink • “Corpthink”

  35. Examples: Statistical Bias • More people die in hospitals than anywhere else, therefore don’t go to the hospital! (unfair sampling) • Similar situation: A medical device designed only for the critically ill • Randomized, controlled trials are part of the answer

  36. Examples: Statistical Bias • Suppose you design a device that will roll a six every time – how many times do you need to test it? • Which results do you report? • Increasingly an issue in medical drug and device trials • 95% significance (p<.05) means that 1 in 20 studies is a false-positive

  37. Psycho-Social Biases • Individual • Primacy: The first option mentioned seems best • Recency: The last option seems best • Group • Groupthink: Consensus rules • “Corpthink”: Desire to please those higher in the chain of command

  38. NASA: Ripe for Disaster? • Huge shift in corporate culture • Space race: Do it at any cost • Increasing cost concerns, cuts, downsizing, resource pressure, etc. • Feynman, Challenger Disaster Report • Engineer estimate of catastrophic failure: 1 in 100 • Management: 1 in 100,000 • “What is the cause of management’s fantastic faith in the machinery?”

  39. More Design Failures • “Recipes for Disaster” • Ignition Source + Flammable Material • … • More Examples • Transportation • Space Program • Software

  40. Hindenburg • German airship • Caught fire while landing in 1937 • Design defect: • Hydrogen? • Skin? http://www.youtube.com/watch?v=F54rqDh2mWA

  41. Apollo 1 • Pad fire during test • Killed 3 astronauts • Design defects: • 31 miles of electrical wire • Pressurized pure oxygenenvironment • Flammable materials • Substandard wiring

  42. Medical Devices & Fire Ignition Source Flammable Materials Anesthetic gas not so much today, ex. O2 Gases in the body, especially GI system Geddes reports ~10 cases of GI explosions during procedures, some lethal! Bedding, clothing Bandages Cleaning solutions, solvents, etc. • Electrocautery • Nerve stimulators • Short-circuit • Electrostatic discharge • Cigarettes • …

  43. Medical Software Design • What type of [medical] technology is least regulated? • Software • There is no professional-level (i.e. PE) certification for software engineering • Less regulation than devices/drugs

  44. Medical Software Design • Design failures are being publicized • Computerized Physician Order Entry • Cedars-Sinai software rollout • Multi-million dollar project scrapped • Software “endangered patient safety” • This story is not unique • Privacy issues • Will software design failures increase?

  45. Summary – Clinical Engineering • Definition of clinical engineering • Engineers’ role in the hospital? • Technology design, management • Increasingly, information management • Clinical research, i.e. VUMC Trauma • Differences between engineering and trade/craft skills (design & analysis)

More Related