Page 1 of 1

Chapter 41. Human Factors and Medical Devices (continued)


Subchapter 41.3. Equipment Checklists in Anesthesia

Events related to medical equipment can be divided into two categories, user-error and equipment failure.43 Health device inspection and preventive maintenance by biomedical or clinical engineering departments have high face validity as an important patient safety practice in reducing equipment failure.

There are many calls in the engineering literature to standardize equipment maintenance.44-46,46 Standardization of protocols is believed to help make the processes more efficient and reduce errors.47 However, it has been difficult to standardize equipment maintenance practices due to a lack of the appropriate units on which to base measurement.46 Some authorities have suggested outcomes based on engineering endpoints such as reliability and accuracy.48 Others have tried to validate a set of maintenance outcome units based on cost or quality metrics.44,45,49 Some engineers have suggested the incorporation of clinical endpoints into medical equipment assessment.48,50 Notwithstanding differing views as to measurement of endpoints, experts uniformly believe that standardization of engineering endpoints is vital to ensure adequately inspected and maintained equipment.46 No studies to date have developed a widely used standardized protocol for equipment maintenance for clinical engineering departments, largely because the lack of standardization of endpoints renders assessing the relative value of any particular maintenance protocol impossible.44-46,48,50 Nonetheless, equipment failure does result in a small fraction of clinical events and thus is an important safety intervention. Hopefully, future studies will help delineate the most effective practices for equipment maintenance processes.

Use of checklists is another practice that helps ensure equipment readiness, particularly for equipment that is needed in critical situations and/or where equipment failure may have dire consequences. For example, a nurse at the beginning of each shift may use a checklist to ensure the readiness of a hospital ward's resuscitation cart ("crash cart") should it be needed (e.g., the defibrillator is plugged-in and charged, the back-up suction pump works, medication is not past its expiration date). Similarly, a perfusion technologist can use a checklist to ensure cardiac bypass circuit and back-up equipment are ready before surgery. Published studies on the effectiveness of equipment checklists largely relate to the use of preoperative checklists to prevent anesthesia equipment failures since, to date, studies on the effectiveness of equipment checklists in medicine have been limited to this area.51-53,54 These studies are reviewed in Chapter 23.

Final Comment to Chapter 41

Human factors testing is yielding important data regarding safe and effective medical device and alarm designs that take into account the users' cognitive limitations. Machines can be designed and redesigned that enhance patient safety, rather than compromise it.

Currently, there are no widely accepted standards for equipment maintenance intervals and protocols. Maintenance endpoints that incorporate clinical events as one component of the endpoint have been suggested. Until a reliable and validated engineering endpoint metric is widely recognized it will remain difficult to investigate the most effective maintenance practices.

Other than the pioneering work in anesthesiology, HFE has been underutilized in medicine. Hopefully, in the near future, more attention will be focused on integrating human factors engineering within all aspects of medical training and practice, which will help create a culture of safety.


1. Handbook of Human Factors and Ergonomics. 2 ed. New York: John Wiley and Sons, INC, 1997.

2. Sawyer D. Do It By Design: An Introduction to Human Factors in Medical Devices. 1997. FDA.

3. Gosbee J, Lin L. The Role of Human Factors Engineering in Medical Device and Medical Systems Errors. In: Vincent C, editor. Clinical Risk Management: Enhancing Patient Safety. 2000.

4. Wiklund M, Gardner-Bonneau D, Carstensen P, Weinger M. Global standardization of human factors for medical devices and systems. In: Proceedings of the Human Factors and Ergonomics Society 44th Annual Meeting. Santa Barbara, CA: Human Factors and Ergonomics Society, 2000: 533-536.

5. Cook RI, Woods DD, Howie MB, Horrow JC, Gaba DM. Case 2-1992. Unintentional delivery of vasoactive drugs with an electromechanical infusion device. J Cardiothorac Vasc Anesth 1992;6:238-244.

6. Cooper JB, Newbower RS, Kitz RJ. An analysis of major errors and equipment failures in anesthesia management: considerations for prevention and detection. Anesthesiology 1984;60:34-42.

7. Ludbrook GL, Webb RK, Fox MA, Singleton RJ. The Australian Incident Monitoring Study. Problems before induction of anaesthesia: an analysis of 2000 incident reports. Anaesth Intensive Care 1993;21:593-595.

8. Bogner MS. Designing medical devices to reduce the likelihood of error. Biomed Instrum Technol 1999;33:108-113.

9. Human Factors Implications of the New GMP Rule. 4-22-1998.

10. Medical Devices; Current Good Manufacturing Practice (CGMP) Final Rule; Quality System Regulation. 61[195], 52601-52662. 10-7-1996. Food and Drug Administration.

11. American National Standards Institute AftAoMI. Human factors engineering guidelines and preferred practices for the design of medical devices (ANSI/AAMI HE-48). Arlington, VA: Association for the Advancement of Medical Instrumentation, 1993.

12. Brown SL, Bogner MS, Parmentier CM, Taylor JB. Human Error and Patient-Controlled Analgesia Pumps. Journal of Intravenous Nursing 1997;20:311-316.

13. Lin L. Human Error in Patient-Controlled Analgesia: Incident Reports and Experimental Evaluation. In: Proceedings of the Human Factors and Ergonomics Society 42nd Annual Meeting. Santa Barbara, CA: Human Factors and Ergonomics Society, 1998:1043-1047.

14. Lin L, Isla R, Doniz K, Harkness H, Vicente KJ, Doyle DJ. Applying human factors to the design of medical equipment: patient-controlled analgesia. J Clin Monit Comput 1998;14(4):253-263.

15. Aucella A, Kirkham T, Barnhart S, Murphy L, LaConte K. Improving ultrasound systems by user-centered design. In: Proceedings of the Human Factors and Ergonomics Society. Santa Barbara, CA: Human Factors and Ergonomics Society, 1994.

16. Sawyer D. Medical device requirements, human factors, and the food and drug administration. In: Proceedings of the Human Factors and Ergonomics Society 44th Annual Meeting. Santa Barbara: Human Factors and Ergonomics Society, 2000: 526-527.

17. Claus P, Gibbons P, Kaihoi, BH, Mathiowetz M. Usability lab: A new tool for process analysis at the Mayo Clinic. In: HIMSS Proceedings. Chicago: Healthcare Information Management Systems Society, 1997:149-159.

18. Gosbee J. Human Factors Engineering is the Basis for a Practical Error-in-Medicine Curriculum. First Workshop on Human Error in Clinical Systems. 1999.

19. Casarett D, Helms C. Systems error versus physicians' errors: Finding the balance in medical education. Acad Med 1999;74:19-22.

20. Frey B, Kehrer B, Losa M, Braun H, Berweger L, Micallef J et al. Comprehensive critical incident monitoring in a neonatal-pediatric intensive care unit: experience with the system approach. Intensive Care Med 2000;26(1):69-74.

21. Woods D. The Alarm Problem and Direct Attention in Dynamic Fault Management. Ergonomics 1995; 38(11):2371-2393.

22. Samuels SI. An alarming problem. Anesthesiology 1986;64(1):128.

23. Finley GA, Cohen AJ. Perceived urgency and the anaesthetist: responses to common operating room monitor alarms. Can J Anaesth 1991;38(8):958-964.

24. Loeb RG, Jones BR, Leonard RA, Behrman K. Recognition accuracy of current operating room alarms. Anesth Analg 1992;75(4):499-505.

25. Momtahan K, Hetu R, Tansley B. Audibility and identification of auditory alarms in the operating room and intensive care unit. Ergonomics 1993;36:1159-1176.

26. Patterson R, Milroy R. Auditory warnings on civil aircraft: the learning and retention of warnings. Final Contract Report 7D/S/0142. 1980. Cambridge, MRC Applied Psychology Unit.

27. Simons D, Frederiks T, Tappel J. The evaluation of an auditory alarm for a new medical device. In: Proceedings of the Human Factors and Ergonomics Society 41st Annual Meeting. Santa Barbara: Human Factors and Ergonomics Society, 1997: 777-781.

28. Edworthy J, Stanton N. A user-centered approach to the design and evaluation of auditory warning signals: 1. Methodology. Ergonomics 1995;38:2262-2280.

29. Leung YK, Smith S, Parker S, Martin R. Learning and Retentiono of Auditory Warnings. siteV2.0/conferences/icad97/leung.pdf. 2001.

30. Edworthy J, Loxley S, Dennis I. Improving auditory warning design: relationship between warning sound parameters and perceived urgency. Hum Factors 1991;33:205-231.

31. Stanford L, McIntyre J, Hogan J. Audible alarm signals for anaesthesia monitoring equipment. Int J Clin Monit Comput 1985; 1:251-256.

32. Burt JL, Bartolome DS, Burdette DW, Comstock JR. A psychophysiological evaluation of the perceived urgency of auditory warning signals. Ergonomics 1995;38:2327-2340.

33. Loeb RG. A measure of intraoperative attention to monitor displays. Anesth Analg 1993;76:337-341.

34. Gurushanthaiah K, Weinger MB, Englund CE. Visual display format affects the ability of anesthesiologists to detect acute physiologic changes. A laboratory study employing a clinical display simulator. Anesthesiology 1995;83:1184-1193.

35. Jungk A, Thull B, Hoeft A, Rau G. Ergonomic Evaluation of an Ecological Interface and a Profilogram Display for Hemodynamic Monitoring. J Clin Monit 1999;15:469-479.

36. Kestin IG, Miller BR, Lockhart CH. Auditory alarms during anesthesia monitoring. Anesthesiology 1988;69:106-109.

37. Sanderson P, Seagull FJ. Cognitive Ergonomics of Information Technology in Critical Care: Contexts and Modalities for Alarm Interpretation. Available at: Accessed June 20, 2001.

38. Xiao Y, Mackenzie F, Seagull J, Jaberi M. Managing the monitors: an analysis of alarm silencing activities during an anesthetic procedure. In: Proceeding of the Human Factors and Ergonomics Society 44th Annual Meeting. Santa Barbara: Human Factors and Ergonomics Society, 2000: 250-253.

39. Bliss JP, Gilson RD, Deaton JE. Human probability matching behavior in response to alarms of varying reliability. Ergonomics 1995; 38(11):2300-2312.

40. Rheineck-Leyssius AT, Kalkman CJ. Influence of pulse oximeter lower alarm limit on the incidence of hypoxaemia in the recovery room. Br J Anaesth 1997;79(4):460-464.

41. Makivirta A, Koski EM. Alarms-inducing variability in cardiac postoperative data and the effects of prealarm delay. J Clin Monit 1994;10:153-162.

42. Rheineck-Leyssius AT, Kalkman CJ. Advanced pulse oximeter signal processing technology compared to simple averaging. II. Effect on frequency of alarms in the postanesthesia care unit. J Clin Anesth 1999;11:196-200.

43. Hyman WA. Errors in the Use of Medical Equipment. In: Bogner MS, editor. Human Error in Medicine. Hillsdale, New Jersey: Lawrence Erlbaum Associates, 1994:327-347.

44. Cohen T, Bakuzonis C, Friedman SB, Roa RL. Benchmark indicators for medical equipment repair and maintenance. Biomed Instrum Technol 1995;29:308-321.

45. Cohen T. Validating medical equipment repair and maintenance metrics: a progress report. Biomed Instrum Technol 1997;31:23-32.

46. Shaffer MJ. Biomedical equipment: maintenance factors, units of measurement, and standards. Med Instrum 1985;19:268-272.

47. Leape LL. Error in medicine. JAMA 1994;272:1851-1857.

48. James PJ. Equipment management risk rating system based on engineering endpoints. Biomed Instrum Technol 1999;33:115-120.

49. Cohen T. Validating medical equipment repair and maintenance metrics, Part II: Results of the 1997 survey. Biomed Instrum Technol 1998;32:136-144.

50. Keil O, Widmann DE. Assessment of the impact of medical devices on the quality of care. QRB Qual Rev Bull 1984;10:278-280.

51. Caplan RA, Vistica MF, Posner KL, Cheney FW. Adverse anesthetic outcomes arising from gas delivery equipment: a closed claims analysis. Anesthesiology 1997;87:741-748.

52. Cooper JB, Newbower RS, Long CD, McPeek B. Preventable anesthesia mishaps: a study of human factors. Anesthesiology 1978;49:399-406.

53. Cooper JB. Toward prevention of anesthetic mishaps. Int Anesthesiol Clin 1984;22:167-183.

54. March MG, Crowley JJ. An evaluation of anesthesiologists' present checkout methods and the validity of the FDA checklist. Anesthesiology 1991;75:724-729.

Return to Contents
Proceed to Next Chapter

Current as of July 2001
Internet Citation: Chapter 41. Human Factors and Medical Devices (continued). July 2001. Agency for Healthcare Research and Quality, Rockville, MD.