ABSTRACT
In recent years, various medical accidents have been reported. However, the number of accidents, incidents and near mistakes with medical equipment is much larger than the number reported officially (Gaba et al., 1995). Reports of critical mishaps show that misuse and human error are more frequently involved than equipment failures (Hyman and Schlain, 1986; Craig and Wilson, 1981; Cooper et al., 1978). Concerning human errors in hospitals, Russell (1992) indicated that avoidable mistakes killed 100,000 patients a year. Human error in medicine, and the adverse events that might follow, are related to problems of psychology and engineering, rather than those of medicine (Senders, 1994). Medical ergonomics has become an important topic in the field of ergonomics. Medical devices play important and life-sustaining roles in the health care sector,
especially in critical-care medical settings, such as Intensive Care Units (ICUs), Anesthesia Workstations, and Operating Rooms (ORs). Deficiencies in medical device design were increasingly identified and addressed in recent years. As is widely accepted, design of medical devices concerns not only the quality of the medical care delivery, but also the patients’ safety and health. Nowadays, usability and risk management in the medical field become an important topic of human factors research. Manufacturers have realized that safe and effective use of a medical device depend on the interaction between the operating environment, user
capabilities, stress levels, and device design, therefore usability issues have to be considered in the design process (Sawyer, 1996). Due to the academic research in usability engineering, the focus of risk analysis
and risk management has already been shifted from technical aspects and human performance to human-machine interaction (HMI). How to improve safety and achieve user-friendly goals by detecting design deficiencies and reducing errors in the design process has increasingly drawn attention of designers andmanufacturers. If design deficiencies or human errors could be detected during evaluations in the design process, numerous medical accidents or injuries could be avoided and more lives, money and labor could be saved. Ventilator machines are used as essential and critical medical devices in Anes-
thesia Workstations, ICUs, and ORs. How to improve the usability of ventilator machines attracts designers’ and ventilator manufacturers’ attention today, and thus how usability tests should be performed. SERVO-i has been an advanced ventilator machine used normally for adult patients. However, the manufacturer of SERVO-i chose it as a target machine for further development due to their future marketing strategy for neonate patients in neonatal ICUs at hospitals. The purpose of the present study was: (1) to detect potential usability problems of a modern complex ventilator machine (SERVO-i) for use in a neonatal ICU, and (2) to investigate the strengths and weaknesses of the target machine (SERVO-i) compared to two reference ventilator machines (Babylog & Stephanie). The aim of the study was to provide an example of using usability testing as a benchmarking tool of ventilator machines in a real hospital setting to propose future redesign ideas.
