Increasing Complexity of Medical Technology and Consequences for Training and Outcome of Care

WH0/HSS/EHT/DIM/10.4

MedicAl devices: MAnAging the Mismatch An outcome of the Priority Medical Devices project

Increasing complexity of medical technology and consequences for training and outcome of care

Background Paper 4 August 2010

Contents

Preface 2 Introduction 3 The use of complex medical devices 4 Problems with medical equipment: evaluation among nurses 5 Learning curves 7 Examples of clinical treatments 8 Colonoscopy 8 Learning curve for colonoscopy 8 Improved instrumentation 8 Minimally invasive surgery 8 Learning curve of minimally invasive surgery 9 Robotic surgery 9 Disadvantages of robotic systems 9 Learning curve of robotic surgery 10 Endovascular interventions 10 Need for training 11 Complications 11 Medical devices used by patients 11 Preferred process of designing medical equipment 13 Different stages of device design, protocols and training 13 Problems related to evaluation of medical devices 13 Standardization 14 Evaluation of the surgical process 15 Peroperative task analysis 15 Achieving the goals 15 Conclusions 16 References 17 2 Medical devices: managing the mismatch—An outcome of the Priority Medical Devices project

Preface

In 2007, at the request of the Government • projections of future burdens of These problems, challenges, and failures of the Netherlands, the World Health disease and disability in the context of amount to a mismatch, rather than a Organization launched the Priority Medical demographic trends; gap, that prevents medical devices from Devices (PMD) project to determine • cross-cutting issues, such as the training achieving their full public health potential. whether medical devices currently on of medical device users, medical device the global market are meeting the needs design, contextual appropriateness The PMD project also produced a report of health-care providers and patients of medical devices, and regulatory Medical Devices: Managing the Mismatch throughout the world and, if not, to propose oversight; aimed at achieving two objectives: the ﬁ rst, remedial action based on sound research. • catalysts of, and barriers to medical to inform national health policy-makers, device innovation and research. international organizations, manufacturers The project gathered the information and other stakeholders of the factors required by conducting literature reviews The original objective of the PMD project preventing the current medical device and surveys, and by convening meetings was to identify gaps in the availability community from achieving its full public of specialist consultants. of medical devices. The findings of health potential; the second, to provide a the project showed that gaps in the basis on which all players in the medical The project addressed various availability of medical devices is not the device scene can together use the ﬁ ndings complementary issues: primary issue, but rather a number of and recommendations of the PMD project • the global burdens of disease and shortcomings spanning several facets of to make public health the central focus of disability; the medical device sphere. This result their activities. • guidelines on clinical procedures for prompted a change of direction in which the management of diseases and the project shifted its focus onto the many disabilities; shortcomings related to medical devices.

This paper is part of a series of documents produced as background material for the PMD project report. The following papers are available as part of this series: 1 A stepwise approach to identifying gaps in medical devices (Availability Matrix and survey methodology) 2 Building bridges between diseases, disabilities and assistive devices: linking the GBD, ICF and ISO 9999 3 Clinical evidence for medical devices: regulatory processes focussing on Europe and the United States of America 4 Increasing complexity of medical devices and consequences for training and outcome of care 5 Context dependency of medical devices 6 Barriers to innovation in the ﬁ eld of medical devices 7 Trends in medical technology and expected impact on public health 8 Future public health needs: commonalities and differences between high- and low-resource settings

This document was developed under the primary authorship of Jenny Dankelman. Her work is gratefully acknowledged. Frank Painter provided valuable input. Thanks are also due to Benjamin Schanker and Dima Samaha for providing valuable contributions in editing, writing, and research.

This publication was produced under the direction of Josée Hansen.

The named authors alone are responsible for the views expressed in this publication. Increasing complexity of medical technology and consequences for training and for outcome of care—Background paper 4 3

Introduction

Technology innovates constantly. This knowledge and expertise. The surgical introduction of minimally invasive surgery simplifies certain aspects of life, and robot is probably one of the most important resulted in higher risks of complications makes others more complex, A fact easily examples of this trend. for patients. observed in the ﬁ eld of medicine. One of the tendencies is to treat patients with While these new technologies are often This paper investigates the consequences procedures that are less invasive, and thanks advantageous for the patient, health of the complexity of medical technology. to new medical techniques and devices, professionals often encounter difﬁ culties It begins with a study of the literature and this trend is increasing. For example, the in using devices associated with these explores the role of nurses, because they use of laparoscopic instruments has meant technologies, which can increase the are often common users of these medical that surgical procedures in the abdominal risk of accidents and complications devices. Four treatment examples are then area are now possible via tiny incisions during surgery. For example, hand–eye discussed. The problems related to the in the skin. Treatments with the use of coordination problems can occur when equipment used and the consequences colonoscopes (for bowels) and catheters using long instruments inserted via small on the ‘learning curve’ of four treatment (for blood vessels) are other examples. incisions or natural openings. Both the methods described in the literature are Many of these procedures are not only degree of freedom and haptic feedback provided. Finally, an outline is discussed very much dependent on technology, but are reduced, and a scope is needed to that could lead to an improved design are also technically complex to perform. present an image on a screen, from which methodology of devices, protocols and Such is the trend: new technologies require the health professional works. Recently, a training. competent health professionals who are report published by the Netherlands Health continuously expanding their breadth of Care Inspectorate (IGZ) (1) showed that the 4 Medical devices: managing the mismatch—An outcome of the Priority Medical Devices project

The use of complex medical devices

Stephenson and Freiherr (2) indicate operating procedures, displays and strategies, in decreasing order of frequency, that according to the Food and Drug alarms (3). were retraining the user, redesigning the Administration (FDA) of the United States of device and telling the user to be careful. America, 9% of the medical device failures With the advent of fast-acting drugs, the Johnson et al. (5) indicate that these results are directly related to use error. They infusion pump is one of the most pervasive suggest that health-care employees put mention that the actual rate of use-related electronic medical device in acute care emphasis on the traditional view of blaming errors is probably much higher. Use errors (hospitals). Nunally et al. demonstrated and retraining the user. That being said, in anaesthesiology, for example, account that the infusion pump is an example of many adverse events in medicine are the for as much as 90% of the deaths and a device around which many errors occur result of poor interface design rather than injuries to patients (2). Indicated mistakes (4), despite the importance of its correct human error. result from poor equipment design, operation. Incident reports in the FDA confusing, poorly-written, or disregarded database implicate interface programming High-quality, functional design of emerging warning labels, and equipment manuals. as a signifi cant aspect of adverse outcomes. medical devices in an increasingly complex Stephenson and Freiherr mention further Nunally et al. performed a study of infusion clinical and technological environment that health-care professionals often have pump-programming performance by requires an understanding of a device’s little time to read the multitude of device experienced health-care professionals context of use, workload, and the manuals or instructions carefully due to in a major urban teaching hospital (4). environment in which it will be used; that constraints of time and capacity. The design Their fi ndings indicated that practitioner is, the device’s ease of use, its placement of medical devices must consider everyday experience with device programming in the clinical workfl ow, and the integration use by health-care professionals or patients does not necessarily increase profi ciency. of user feedback in the design process (6), to make them easier to use. Many experts This suggested that a complex menu all of which provide maximum benefi ts believe this approach has the most potential structure makes programming diffi cult and to health-care quality. This is all part of for reducing use errors (2). ineffi cient – it impedes the development of what is called ‘human factors engineering’, mental models suffi cient for reliable device which involves the application of principles While an adverse event involving a medical operation. In effect, this causes operators about human behaviours, abilities and device is often attributed to either use error to become disoriented in the interface limitations, to the design of tools, devices, or device failure, the causes are typically structure (4). environments, and training in order to multifactorial (3). In an investigation of optimize human performance and safety. several incidents involving medical devices, The design of a device’s user interface often Amoore and Ingram (3) explore the various contributes to the chance of a user making It is important that medical device causes of the incidents and the protections an error in using the device. However, there manufacturers involve such engineering that minimized or prevented adverse is evidence that the majority of such errors in the design process from the outset and consequences. They mention the following are attributable solely to the user and that perform usability testing. Furthermore, it relevant user factors: mistakes, omissions the primary method of error prevention is important for a multidisciplinary team and lack of training, with background is to retrain the user (5). Johnson et al. to be involved in product evaluation factors – device design, storage conditions, conducted a qualitative study to assess and purchasing decisions. Health-care or hidden damage; misleading indicators; health-care employees’ attitudes towards organizations should expect an optimized confusing software features; and physical device use errors and the prevention of and tested (standardized) user interface layout of equipment when in use – causing adverse events (5). The top three reported in the medical devices they purchase (7), the adverse events in many of the incidents factors leading to the adverse event were because such qualities are critical to patient (3). Protections that prevented or minimized the user, design problems and lack of safety. the consequences included staff vigilance, training. The top three reported prevention Increasing complexity of medical technology and consequences for training and for outcome of care—Background paper 4 5

Problems with medical equipment: evaluation among nurses

During the past decade, health-care least 90% of respondents indicated that In 2008, the Technical University Delft, in delivery has seen the introduction of their fi rst encounter with a device was the Netherlands (MISIT group, Department ever more sophisticated and complex when they simply learned its purpose, of Biomedical Engineering) received equipment. This means that the medical function, and operating concepts (8). remarkable conerns from two hospitals devices fi rst used in critical and intensive The most frequently identified method (one academic and one peripheral). “Our care units are now integral requirements in of initial learning was reading the user [operating room (OR)] nurses are not the delivery of patient care in acute wards. instruction manual. Furthermore, 87.1% of educated well enough anymore to handle Although physicians are responsible for the respondents indicated they had received the equipment in the OR; can you help us?” treatment, it is often the nurses who are the instruction about a device from another To investigate this problem, two pilot studies primary users of such medical devices (8). staff member, typically another registered were started. The Technical University nurse (8). Another fi nding was that medical Delft, in the Netherlands performed an The influence of the operator on the device use causes more than 75% of staff inquiry of 27 OR nurses in a peripheral effective and safe application of medical nurses to feel stressed. In addition, this hospital to get insight into the problems technology is generally underestimated. study showed that around 10% had used with equipment use during laparoscopic In an investigation on incidents involving a medical device improperly, which had cholecystectomies. The nurses indicated a defi brillators in the US (2), it was concluded later harmed a patient (8). In response to number of diffi culties using the equipment. that the majority of the incidents were due these fi ndings, McConnell and Murphy (12) These included the: to incorrect operation and maintenance. have concluded that the introduction of • camera (white balance is sometimes A study of 2000 adverse incidents in sophisticated health-care technology does forgotten, focusing is diffi cult because operating theatres in Australia showed that not guarantee high-quality patient care. of the plastic sheet, connection to the only 9% were due to pure equipment failure monitor can be too diffi cult due to the (9). In two reports on the use of critical care A study by Kiekkas et al. (13) aimed to numerous wires to connect); equipment by nursing staff, 19% (10) and determine the perceptions of nurses who • light source (image is sometimes 12.3% (11) of nurses, respectively, indicated work in critical-care units about positive too dark, and solution to problem is that they had used equipment improperly, and negative effects related to the use of not clear; if light source needs to be which had consequently harmed a patient. technological equipment and to identify replaced, nurses do not know how to do It is inevitable that there are numerous relationships between these perceptions it or where to fi nd a new bulb); adverse or ‘near-miss’ incidents that go and demographic characteristics of study • laparoscope (scope can cause burns); unreported (11). Fouladinejad and Roberts participants. Kiekkas et al. surveyed 122 • diathermy devices (a number of different (11) also showed that training in the use critical-care nurses to elicit their perceptions devices are used, with different settings of equipment is a very minor activity, with regarding the use of technological and not always enough time to check less than 1% of departmental time spent equipment. The outcome of this study was the settings, or differences between the on providing or receiving training (staff that the majority of nurses recognized the settings are not always explained); with higher levels of expertise required less positive effects of equipment regarding • insufflator (not enough experience assistance from technical personnel). They patient care and clinical practice. However, with connecting CO2 gas, no warning concluded that critical-care equipment at the same time, they agreed that use of when the bottle is almost empty, faulty can be utilized more fully, cost-effectively equipment possibly leads to increased risk connection of cables and wires, use of and safely if a formal and regular training due to human errors or mechanical faults, foot pedals, numerous cables); and programme is implemented (11). increased stress and restricted autonomy of • monitor (when the image is poor or nursing personnel (13). The use of machines missing, it is too diffi cult to fi nd the In another study, 323 registered nurses does not add to nursing prestige and this problem, it is diffi cult to achieve the working in a 500-bed tertiary care hospital may be related to decreased autonomy. right colour settings; when someone were surveyed to determine what and how Human errors, mechanical faults and incorrectly adjusts the knobs, it requires they initially learned about the medical increased stress do not seem to come as a lot of time to readjust the settings/ devices they use, and the consequences a result of time constriction but rather of connections). of their use (8). McConnell and Fletcher inadequate education (13). Therefore, it is found that the most frequently identifi ed desirable for undergraduate and continuing Some general problems with equipment methods of initial learning were trial education to respond efficiently to the were also mentioned: equipment is not well and error (self-taught) and reading the needs of contemporary critical care. introduced to the nurses; and if something is user instruction manual. Furthemore, at not working the nurses do not have enough 6 Medical devices: managing the mismatch—An outcome of the Priority Medical Devices project background to solve the problem. Instruction trends are needed if practitioners are to more diffi cult. The Joint Commission on manuals are too complex, are not available maintain competence (14). These studies Accreditation of Healthcare Organizations in native languages and can often not be indicate that appropriate and certified (JCAHO) requires that all equipment users found. Therefore, equipment that is not used educational and training strategies can (clinicians and nurses) be trained annually daily is particularly prone to use error. be used (or designed) to address the in the proper procedures for the equipment aforementioned clinical governance and they use, and that the training should be The OR nursing environment is infl uenced risk management issues. documented (15). Training for clinicians to by requirements for increased acuity and use an instrument is called ‘skills training’; patient throughput, and by constantly Training equipment users to operate for nurses, the term ‘education’ is used. changing technology (14). The specialty medical equipment effectively and All learning related to new instruments is practice of the OR nurse is complex. safely is one of the most important and referred to as the ‘learning curve’; this will Although the specialty practice is based diffi cult tasks of clinicians/engineers (15). be discussed in turn. on the core body of nursing knowledge, Hooper et al. (15) indicate that as medical continuous expansions of knowledge and equipment proliferates and becomes more skills in medical device training and current complex, the task of training also becomes Increasing complexity of medical technology and consequences for training and for outcome of care—Background paper 4 7

Learning curves

A learning curve in the context of skills of surgical anatomy. The type of training new technologies? Currently, individual training refers to the time taken and/ the surgeon has received is also important: practitioners are responsible for the or number of procedures an average for example, the use of box trainers and ethical use of new (to them) technologies. practitioner needs to be able to perform practising on animal tissue for learning It is physicians’ ethics that govern their a procedure independently with an laparoscopic surgery techniques have use of new technologies; physicians are acceptable outcome (16). A complex been shown to facilitate the process responsible for the requisite training and hierarchy of factors is involved in the of learning (19). The slope of the curve experience to know the intervention is safe learning curve (17), factors like guidelines, depends on the nature of the procedure for their patients. Institutional practitioner protocols and standards for clinical and frequency of procedures performed credentialing at the local level, despite its governance agreed upon by the medical in a speciﬁ c time period (Figure 1). Many faults, is often the primary control of the use fraternity are vital. Institutional policies, the studies suggest that complication rates of a (new) technology. surgical team and the case mix (the types are inversely proportional to the volume of of patients treated in an institution) are also the surgical workload (20). The rapidity of Leaving the responsibility of setting relevant. Another factor is the individual, learning is not signiﬁ cantly related to the standards regarding learning curves in e.g. the characteristics of the surgeon, surgeon’s age, size of practice or hospital the hands of individual physicians or local such as attitude, capacity for acquiring setting (21). institutions is ultimately subjective; it is new skills and previous experience (18). possible that this subjects patients to a The learning curve, therefore, may depend Who decides when a learning curve higher risk of complications (e.g. during on the manual dexterity of the individual has been met? Who is responsible for the early phase of learning of laparoscopic surgeon and his background knowledge setting and monitoring standards for procedures). The importance of proper training prior to the use of medical devices increases as medical technology advances Figure 1: Learning curve related to design – increasingly complex surgical procedures Quick learning curve: well-designed device Slow learning curve: poorly-designed are being carried out e.g. laparoscopic (i.e. effective human factors engineering) device (i.e. not easy to use) that results surgery. Leaving the responsibility of that requires little training. in poor performance even after extensive creating credentialing programs to training. individual physicians could be a risk. Unfortunately, depending on the country, there may be few current checks on the expertise of surgeons aspiring to be Training Training laparoscopic surgeons. Human performance Human performance

Time Time 8 Medical devices: managing the mismatch—An outcome of the Priority Medical Devices project

Examples of clinical treatments

Four examples of clinical treatments where endoscopists at each level of experience donut functions like a circular caterpillar; medical instruments play a critical role will (numbers of performed procedures) in the it is constructed from three fl exible stents be discussed, as will one example of a ability to perform a complete colonoscopy. that have high friction with the intestinal ‘simple’ device used by patients. Hence some endoscopists need more wall. The resulting Rolling-Stent Endoscope training than others to achieve competence. contains a steerable mechanism by which Dafnis et al. (25) suggested monitoring the tip can be bent in all directions over a Colonoscopy endoscopists to maintain and improve very large angle. Colonoscopy is a standard medical performance. Another method to reduce procedure in which a long and flexible the learning curve is the use of simulators endoscope is inserted into the rectum for (22). Minimally invasive surgery inspection of the large intestine or simple Minimally invasive surgery started in 1987 interventions. Patients have indicated The impact of endoscopic training on with the fi rst laparoscopic cholecystectomy. dissatisfaction with procedures performed procedural time and cost was investigated This operation technique is based on by trainees, particularly those early in the using a large database (26). It was shown that access to the body of a patient via a limited learning curve (22). Pushing the endoscope involvement of a surgical resident prolonged number of round cannulas (trocars inserted tip from its distal end via a long and fl exible procedure time by 10 to 37%, with an via small incisions in the skin) (30). The tube leads easily to buckling when the estimated academic institutional fi nancial method of access allows the introduction tip meets sharp curves in the intestinal loss of US$ 500 000–1 000 000 per year. of thin rigid instruments to treat the internal wall. Buckling is accompanied by painful The implementation of training simulators in tissue of a patient. In order to be able to cramps and makes it diffi cult to complete the training process could partially reduce observe the actions, a small camera is the procedure. Additionally, an increased the adverse fi nancial impact associated with introduced through one of the trocars. frequency of minor adverse events training and could also decrease adverse Minimally invasive surgery can be applied associated with such procedures has been events and discomfort for patients (22). to the abdomen (laparoscopy), chest described (23). (thorascopy), and joints (artheroscopy). Improved instrumentation As this discussion is mainly concerned Learning curve for colonoscopy One way to solve the steering problems with the abdominal applications of the Steering errors are one of the reasons for the associated with colonoscopies would be technique, most of the material presented high learning curve of colonoscopy. Current to develop a joystick mechanism. In an herein will pertain to laparoscopy. The steering wheels do not work intuitively; the experimental setting, the joystick-controlled laparoscope equipped with a video camera wheel is not ergonomic and controlling colonoscope allowed for better control, system is used to observe the interior of the tip of the colonoscope is diffi cult. As a shorter intervention times and a shorter the abdomen. It consists of a rigid tube, result, it is diffi cult to control the endoscopy learning curve (27). Despite such fi ndings, containing a lens system and an optical by combinations of horizontal and vertical the company that is the market leader in the fi bre channel. This channel is connected movements offered by the steering wheels. fi eld of colonoscopes has not improved the to a xenon light source that illuminates the ergonomics of the older design. operation scene. The lens is connected to A study by Tassios et al. (24) evaluated over the video camera and a monitor. In this way, 1400 colonoscopies with trainees, and Other possibilities to improve steering are a two-dimensional (2-D) image is presented showed that more than 180 procedures still in experimental stages, e.g. inchworm to the surgeon, enabling him to observe are required before a trainee can be devices specialized for locomotion in the the internal anatomy of the patient and to considered competent. An expert (someone colon developed at the Scuola Superiore control instrument handling. with more than 430 colonoscopies) had Sant’Anna, in Pisa, Italy (28). These have a success rate of 91% whereas trainees two types of actuators: a clamper and an There are several limitations when achieved a success rate of not more than extensor. The clamper is used to adhere or using the minimally invasive technique 77% after practising in 180 procedures. A clamp the device onto the substrate while (30). Most of these limitations involve the study by Dafnis et al. (25) also showed that the extensor generates a displacement in technical and mechanical nature of the completion rate increased with experience. the colon. equipment. For laparoscopic surgery, They concluded that the major reason the surgeon manipulates the tissue via for differences in completion rate is the A new way of locomotion developed in laparoscopic instruments, inserted through difference in competence of endoscopists. Delft (29) is based on a rolling donut that is small incisions with limited freedom of They also found large variations between positioned around the endoscope tip. The movement; the surgeon has no direct Increasing complexity of medical technology and consequences for training and for outcome of care—Background paper 4 9 contact with the tissue (no manipulation by Complex procedures, such as prostatectomy Signifi cant improvements were seen with hand). Due to friction and, in general, the and nephrectomy, require more time trocar insertion, crural closure, division of poor ergonomic design of the instruments, to learn. Vallancien et al. (37) reported short gastric arteries, and fundoplications. the feedback of perceptive information is that more than 50 difficult operations An interesting fi nding reported is that in reduced (31). Working remotely means no are necessary to acquire adequate skills training every task should be repeated three-dimensional (3-D) visual information skills, provided that such operations are at least 30 to 35 times for maximum is available, which further compounds the performed suffi ciently frequently. They also benefi t (43). The distribution of training over diffi culties of this technique. Consequently, reported that the learning curve shows that several days has been shown to be superior the surgeon receives only indirect eight of 10 of the major complications of the to training in one day (44). information, which is the most important procedure essentially occurred during the distinction between the laparoscopic fi rst 100 cases. Soulie et al. (38) observed procedure and open surgery. a decreased complication rate (from 9% to Robotic surgery 4%) after the fi rst 100 procedures. A recent technology in the fi eld of surgery The risk of complications during laparoscopy is robotic surgery. A surgical robot is a ranges between 2% and 4% – higher than As far as training is concerned, the master-slave system with multiple arms in open abdominal surgery (1). One of the introduction of laparoscopic techniques operated remotely by the surgeon from a reasons for such a high risk is intra-operative in surgery caused many unnecessary master console. The surgeon controls a injury: the traumatization of soft tissues complications (1). This resulted in the robotic arm that operates on the patient, while trying to securely grasp, stretch, and development of laboratories to hone skills, and an endoscopic camera provides a 3-D manipulate them. In a national survey of involving the use of box trainers with image to the surgeon. The instruments are US hospitals, Deziel et al. (32) found that either innate or animal tissues but without cable driven, and provide seven degrees laparoscopic cholecystectomy had a objective assessment of skill acquisition of freedom. The system gives the surgeon signifi cant rate of bile duct injuries that, (19). Simulation systems, and especially the illusion that the tips of the instruments in half of the cases, were recognized post- virtual reality (VR) simulators, may are in his/her hands, giving the impression operatively and mostly required anastomotic provide a solution to the lack of objective of being at the surgical site. The motivation repair. Fletcher et al. (33) reported that, in assessment. The term `virtual reality´ refers to develop surgical robotics is rooted in Western Australia, after the introduction of to a computer generated representation the desire to overcome the limitations of the laparoscopic cholecystectomy, the cases of an environment that allows sensory current laparoscopic technologies (limited with intra-operative injury increased from interaction, thus giving the impression of degrees of freedom, mirroring and scaling 0.67% in 1988–1990 to 1.33% in 1993– actually being there. The advantages of VR of movement, and the ‘fulcrum effect’),1 as 1994. Laparoscopic cholecystectomies have simulators are the automatic measurement well as to extend the benefi ts of minimally a nearly twofold higher risk of damage to the of, and feedback on performance; and invasive surgery. Currently, there is only one bile duct, bowel, and vascular structures unlimited repetitions of exercises in a trademark of surgical robot commercially than does open surgery (33). To prevent challenging and safe training environment available. Lafranco et al. (45) gave an these errors root cause analyses can be to strengthen psychomotor skills. In the extensive overview of the advantages and performed. past decade, several VR simulators have disadvantages of these robotic systems been developed and studied (39). However, (Table 1). Learning curve of minimally invasive the training effects of VR simulators are still surgery not fully understood, and educators are The health-care market is becoming more The enthusiasm for laparoscopic surgery reluctant to structurally adopt VR simulators and more competitive. Many institutions has increased rapidly over the past decade. into the surgical curricula on a large scale are interested in presenting themselves as There is a large amount of literature until tests prove its effi cacy. Validation of having the most advanced technological showing advantages of minimally invasive a new VR simulator is essential in order equipment and the latest treatment and surgery and its acceptance by the public. to determine how the simulator should be testing modalities (45). Use of a surgical Laparoscopic surgery is more diffi cult to used in surgical curricula (40). A recent robot fulfi ls this purpose. Indeed, robotic master and is associated with a longer prospective randomized controlled trial devices seem to have more of a marketing learning curve than conventional open showed that the use of a VR simulator role than a practical one (45). Whether or surgery. The skills required for laparoscopic combined with box training leads to better not robotic devices will grow into a more surgery are not intuitive. The surgeon needs laparoscopic skill acquisition (41). practical tool remains to be seen. specifi c psychomotor skills to control the long instruments through a pivoting point, Scheerer et al. (42) determined the benefi t Disadvantages of robotic systems to compensate for the problems with of training in a laboratory for senior There are several disadvantages to these reduced depth perception and viewing residents. Training included laparoscopic systems (45). First of all, robotic surgery is the 3-D anatomical environment on a 2-D suturing, as well as didactic and laboratory a new technology and its uses and effi cacy monitor image and to compensate for the components. They showed that the have not yet been well established. To date, reduced haptic feedback. These aspects performance scores of surgical residents most studies conducted have looked at lead to a long learning curve, which has increased signifi cantly and persistently as been documented (34–36). a result of focused laboratory skills training. 1 The fulcrum effect refers to the interference caused by the body wall while using instruments during surgical procedures. 10 Medical devices: managing the mismatch—An outcome of the Priority Medical Devices project

overall operating time, which includes setting Table 1. Advantages and disadvantages of conventional laparoscopic up the robotic system, the standard open surgery and robot-assisted surgery procedure provides a major advantage. Although many papers (>70) were included Conventional laparoscopic surgery Robot-assisted surgery in the review by Ficarra et al. (50), most of ADVANTAGES Small and (relatively) simple instruments to use More depth-perception cues the studies were considered as level 4 of Affordable Improved dexterity through: evidence and only three nonrandomized • seven degrees of freedom Ubiquitous • elimination of the fulcrum effect comparative studies were considered as level Proven effi cacy • ability to scale motions 3b of evidence.2 While RALP appears to be a (Limited) haptic feedback Improved ergonomic design for surgeons feasible procedure, a hypothetical superiority DISADVANTAGES Less depth-perception cues Very expensive complex equipment over the conventional procedure remains to Compromised dexterity due to: High start-up and maintenance costs be proven. More high-quality randomized • limited degrees of motion clinical trials with long-term follow up, using Requires a highly-trained staff with extra • the fulcrum effect validated methods of assessment, need to • scaling of instrument tip movements relative skills in manipulating the robot to hand movements Benefi t not proven in randomized trials be performed. Poor ergonomic design No haptic feedback Robotic surgery techniques are still (45) Source: Adapted from Lafranco et al. . developing. The applications for robotic surgery are expanding rapidly in many different surgical disciplines. Only time will feasibility, with few long-term follow-up problems associated with their current size. tell if the use of these systems justifi es their studies. If robotic surgery is implemented, Others believe that larger operating suites cost. If the cost of these systems remains many procedures will have to be redesigned with multiple pedals and wall mountings high and they do not reduce the cost of to optimize the use of robotic arms and may be needed to accommodate the extra routine procedures, it is unlikely that there increase effi ciency, though these will likely space requirements of robotic surgical will be a robot in every OR and thus unlikely improve over time. systems. Regardless, the lack of compatible that they will be used for routine surgeries. instruments and equipment with robotic Questions about malpractice liability, Another disadvantage of these systems is systems is also a potential disadvantage credentialing, training requirements, their cost. With a price tag of US$ 1.4 million, as it could increase reliance on tableside licensing, and safety are all valid. It their cost is often prohibitive. Whether the assistants to perform part of the surgery (46). remains to be seen if robotic systems will price of these systems will fall or rise is a Without doubt, new technologies will be replace conventional instruments in less- matter of conjecture. Some believe that with developed to address shortcomings such demanding procedures. improvements in technology and as more as this. Indeed, most of the disadvantages experience is gained with robotic systems, identifi ed will be remedied with time and Learning curve of robotic surgery the price will fall (46). Others believe that improvements in technology. Chang et al. (51) showed that incorporation improvements in technology, such as of the surgical robot into surgical practice haptics, increased processor speeds, and Many studies concluded that a large number requires dedicated training to achieve more complex software will increase the of robotic laparoscopic procedures are safe mastery. They studied the learning curve for cost of these systems (47). Also at issue is and feasible, for example, robotic-assisted intracorporeal knot tying in robotic surgery. the problem of upgrading and maintenance laparoscopic radical prostatectomy (RALP) Baseline laparoscopic knot completion took of these systems; how much will hospitals (48,49). At the moment this treatment is 140 seconds (range 47–432), whereas and health-care organizations have to the most important application for robotic robotic knot tying took 390 seconds. After spend on maintenance and upgrades and surgery. A review by Ficarra et al. (50) initial robotic training, time decreased by how often? In any case, many believe that contributes greatly to the evaluation of the 65% to 139 seconds. With more training, to justify the purchase of these systems they results of RALP. The authors observed that completion times and composite scores must gain widespread multidisciplinary use RALP has been widely used in the past fi ve were improved and errors were reduced. (45, 47). Due to the complex technology used, years. They state that the learning curve failures can easily occur and therefore the is shortened compared to conventional Recently a new training device came on the safety of these systems remains an issue laparoscopic radical prostatectomy. The market that can be used to train surgeons in that requires further investigation. oncologic data are only preliminary, but it using the robotic operating system. seems reasonable to assume that RALP will Additionally, the size of these robotic allow for better continence recovery than systems is a disadvantage. Operating rooms conventional procedures. According to the Endovascular interventions are already crowded with personnel and most recent comparative analyses, blood loss During endovascular interventions in equipment; it may be diffi cult for both the may be diminished in RALP compared to the surgical team and the robot to fi t into the OR. standard radical prostatectomy procedure, 2 The Oxford Centre for Evidence-based Medicine ranks evidence obtained from Some suggest that miniaturizing the robotic but no signifi cant advantage is found in terms non-consecutive study or without consistently applied reference standards as level 3b evidence. Evidence obtained from case-control study, poor or non- arms and instruments will address the of postoperative pain, however. Concerning independent reference standard is classifi ed as level 4 evidence (http://www. cebm.net/index.aspx?o=1025,accessed 20 February 2010). Increasing complexity of medical technology and consequences for training and for outcome of care—Background paper 4 11 interventional radiology a guide wire/ be applied as a full-scale training tool. radiologists, cardiologists, neurologists, catheter is introduced into the vascular Problems exist with bench models as and neurosurgeons. Neequaye et al. (61) system. Access to the internal body is well, because objective assessment of indicated that there are potentially achieved by creating an access to the performance is diffi cult to obtain. Training catastrophic results of technical errors in bloodstream by introducing a sheath. This on VR simulators does not have these carotid artery stenting as evidenced by method allows the introduction of catheters, problems and seems therefore to be a good the recently published EVA3S trial, which guide wires, balloons, stents and other alternative. However, the effectiveness and was terminated prematurely as a result of devices and instruments. An X-ray machine effi ciency of VR trainers in interventional an excess stroke and death risk (9.6% in with real-time fluoroscopy provides the radiology have not yet been studied. It is carotid artery stenting compared with 3.9% interventional radiologist with a 2-D image only recently that VR training for vascular after endarterectomy) (64). The trial was of the operating region and the instruments interventional radiology procedures criticized because relatively inexperienced being used. Although interventional has become available. Most studies interventional radiologists performed the radiology has great benefi ts for the patient on VR training in medicine come from carotid artery stenting. To ensure that only (being minimally invasive which facilitates publications discussing endoscopic appropriately trained individuals carry out accelerated recovery), it poses a series of surgery, or minimally invasive surgery such high-risk procedures, structured challenges to the interventional radiologist, (52,58–60), and further studies are needed to training programmes underpinned by including (52): determine the effectiveness of VR training objective measures of profi ciency, must be • difficulty in manoeuvring the long in radiology. developed. Neequaye et al. (61) concluded fl exible catheter; that tools for such programmes are • friction with the vessel wall, which While similarities exist between already available, but that organization hinders movement of the catheter; interventional radiology and endoscopic of such programmes needs to make full • poor force feedback from the catheter surgery (in both fi elds special long tools use of modern simulation techniques tip, resulting in unknown pressures at are used, inserted through small incisions), for technical and non-technical skills the tip; certain interventional radiology techniques, training. Unfortunately, the effectiveness • no direct sight line; visual feedback is such as stenting and embolization, of VR endovascular training is not yet only obtained via an X-ray image; and have their own intrinsic demands, end- established (61). Furthermore, Neequaye • loss of depth perception, since only 2-D points and complications. Furthermore, et al. (61) indicated that reliability, feasibility visual information is available. interventional radiology techniques are and validity are still issues with these not necessarily related to any ‘classical’ training programmes. These challenges suggest that performing vascular surgical techniques, either. All of an intervention using a catheter is very this makes the demands for VR training in diffi cult. Such diffi culties emphasize the this fi eld unpredictable. Medical devices used by patients need for effective training methods for Devices are increasingly being moved from interventional radiologists, with the primary Neequaye et al. (61) performed a literature exclusive use in specialized health-care goal of improving the efficiency of the study on the methods available for settings to community- and home-based procedure and reducing errors. endovascular skills training and assessment care. In these new environments, devices of skills. This fi eld also requires a different may be used by untrained and unskilled Need for training set of skills than does open surgery. It users (e.g. patients) (65). An example is To be able to meet the growing demands of was shown that simulation based training the hand-held, battery-operated meter interventional radiology and endovascular shortens the learning curve. Lin et al. (62) that patients with diabetes use to check therapy, many more interventional analysed outcomes of patients undergoing blood glucose levels. In an article by radiologists need to be trained in procedures carotid artery stenting; the outcomes Rogers et al. (66), the authors showed that that are becoming increasingly complex. demonstrated fewer procedure-related a device that is classifi ed as `simple´ by Until recently, fellows obtained their fi rst complications, reduced fl uoroscopy time, the manufacturer, may not be simple in basic skills training during diagnostic and lower contrast volume with increased practice. A task analysis was conducted angiography procedures. This traditional physician experience. A number of studies showing that three steps were involved method of training is disappearing, indicated that simulation-based training in using the blood glucose meter, but however, because other diagnostic methods allows the early part of the learning curve implementation of those steps required the are becoming available. This gap in training to take place without exposing patients to user to perform 52 sub-steps (66). Special can be fi lled in several ways. unnecessary risks (62,63). Iliac and renal instruction/training was given to the user, angioplasty showed similar improvements but these instructions were too complex to Training on animals, bench models (skill with simulator training (61). understand, or were poorly worded (66). A boxes) and VR training have all been global measure of readability showed an 8th suggested as solutions to this problem Complications grade education was required to read the (53–57). The fi rst solution, however, has Neequaye et al. (61) and Mas et manual (readable by approximately 58% been met with considerable resistance by al. (64) reported that a range of clinical of the US population). Diggory et al. (67) the public in many countries; furthermore, specialists are interested in performing evaluated the use of an inhaler by elderly animal experimentation is too costly to carotid artery stenting, e.g. interventional patients (aged between 71 and 91 years 12 Medical devices: managing the mismatch—An outcome of the Priority Medical Devices project old, with a mean age 83) and found that allowing defi nition of the relevance of the the Bundesinstitut für Arzneimittel und 24 hours after being trained in its operation, error itself. The authors give an example: Medizinprodukte, BfArM; Germany’s 65% of them could not use the device at in a critical situation, a haemolyzed sample Federal Institute for Drugs and Medical all. Comparable fi ndings were discovered is probably less problematic than sample Devices) and found a large number of when evaluating the use of hearing aids (67). mismatching or a turn around time that is product defects, but also a large number too long. However, abnormal haemolysis of laboratory use errors. They suggested The in vitro diagnostic device is another that prevents sample analysis can lead to a number of measures, such as suffi cient example of a device that can be potentially a request for a new sample, which prolongs information and training of patients using in misused. Laboratory errors can negatively the turn around time and could potentially vitro diagnostics (IVDs), include information impact patient safety (68). Bonina et be very harmful for critical patients (68). on the limitations of the methods and the al. argue that it is important to classify Siekmeier and Lutz (69) analysed all in risks related to erroneous results, as well laboratory errors by relating them to their vitro device notifications between 1999 as relevant causes of user errors that could potential effects on patient outcomes, and 2006 in Germany (registered by infl uence safety (69). Increasing complexity of medical technology and consequences for training and for outcome of care—Background paper 4 13

Preferred process of designing medical equipment

High-quality, functional design of emerging et al. (70) can be used for this process. Training has two aspects: a learning aspect medical devices in an increasingly complex They describe three stages of evaluation: for the resident to acquire new tasks, and clinical and technological environment 1) technical experiments, 2) simulated a controlling aspect for the supervisor to requires an understanding of the device’s experiments and 3) clinical settings. evaluate the correctness of performance context of use, workload, and the and the effi cacy of learning (75). Training environment in which it will be used. That New medical devices must first have a can also be initiated at three stages (70). is, the device’s ease of use, its placement technical evaluation to assess reliability and Stage 1 includes training in basic tasks and in the clinical workfl ow, and the integration safety, as well as to test specifi c functions. coordination (e.g. hand-eye coordination of user feedback in the design process (6), According to den Boer et al. (70), the tasks, suturing tasks, or VR simulators) all of which provide maximum benefits functionality, safety and ergonomics form (76–78). Stage 2 includes simulated to health-care quality. This is all part of part of the technical evaluation and could protocol tasks, tissue handling, operation ‘human factors engineering’, which involves be analysed in a laboratory setting. The planning, and risk prevention; animals or the application of principles about human technical evaluation should be followed by VR simulations can be used to improve behaviours, abilities and limitations to the an experimental evaluation simulating the surgical skills at this stage (59, 79–82). design of tools, devices, environments, clinical setting, without risk to the patient Stage 3 includes ensuring analysis of and training in order to optimize human (71–73). After the quality and safety of the both the correctness and effi cacy of task performance and safety. prototype have proven suffi cient, evaluation performance (70, 83). in clinical practice is needed (70).

Different stages of device It is valuable for protocols, in addition to Problems related to evaluation of design, protocols and training new technology, to be tested in a simulated medical devices The development of improved instruments, clinical setting (74). Furthermore, determining There are a number of problems inherent protocols and training tasks can reduce whether or not the quality and effectiveness in the way new medical devices are errors and enhance the quality of of the new protocols are signiﬁ cantly better is evaluated (70). Issues include the lack medical interventions. Therefore, it is needed prior to implementation in a clinical of clinical trials and thorough analyses valuable for continuous evaluation of setting. It is valuable if training in these new of new devices/surgical instruments. In these improvements to be considered. protocols is present at each of the three addition, FDA approval of a new medical The methodology described by den Boer stages of development (70). device does not automatically indicate that the performance is better (84). The limited surveillance that products receive after entering the market can result in less effective treatments and delays in Table 2. Stepwise analysis of quality and efﬁ ciency in medical device design identifying risks (84).

Evaluation parameters Generally, case studies are used to determine the ‘feasibility’ of medical Stage Device development More depth-perception cues Training programme devices. This evaluation includes a 0 – Instrument tests Reliability —— number of problems (70), which often are Instrument characteristics Safety not mentioned. The studies tend to be 1 – Technical experiment Functionality — Basic tasks or drills performed by top experts, and results Ergonomics Coordination may not refl ect average outcomes. There Safety Correctness is generally not a standard on which to 2 – Simulated experiment/ Functionality Safety Simulated surgical actions evaluate instruments, and objectivity is Animal experiment Ergonomics Quality Simulated protocol tasks Safety Tissue handling jeopardized when the company pays for the Planning operation evaluations. Surgeons are unlikely to blame Risk prevention the instruments, focussing instead on other 3 – Clinical setting Functionality Safety Planning operation factors that may have led to complications. Ergonomics Quality Risk prevention Effi ciency Effi ciency Correctness A study by Verdaasdonk et al. (85) showed Safety Effi ciency that most incidents with equipment are

Source: den Boer et al. (70). not reported, meaning the problems with 14 Medical devices: managing the mismatch—An outcome of the Priority Medical Devices project a complex medical device will not easily Ergonomic improvements and standard- Ergonomic design of instruments and the become visible; and as a consequence no ization of equipment in conjunction with OR can improve treatment by decreasing action will be taken to improve the device. checklists prior to surgery have been fatigue and discomfort of the surgeon suggested (85). Variation in medical (91–93). Additionally, methods to assess Standardization devices between hospitals (and even mental and physical workloads on surgeons A number of studies have shown that within the same hospital) is one of the could be developed and applied, in order between 39% and 46% of adverse events causes of these accidents. Suppose, for to detect and to reduce pressures (91–93). resulting from misuse of medical devices example, that all cockpits in a particular Additionally, methods to assess mental and take place in the OR (86–89). In most of airplane were designed according to the physical workloads on surgeons could be these studies, the cause is only indicated specifi cations of the captain. This would developed and applied, in order to detect as operation related. A recent observational result in an unlimited number of design and to reduce pressures (94,95). An article by study (85) investigated the incidence of variations. For safety reasons this does Rogers et al. (66) demonstrated how human problems with technical equipment during not happen. Standardization is a key factors engineering could be applied to laparoscopic procedures. In 87% (26/30) issue in the fi eld of medical devices, and glucose meters and medical devices in of the procedures, one or more incidents would reduce the number of accidents. general. Blood glucose meters, specifi cally with technical equipment (49 incidents) Except for the maximal size, there are no designed for patient use, were reviewed via or instruments (9 incidents) occurred. In clear guidelines in building or outfi tting a task analysis. Users reported a number of 22 of those incidents (45%), the technical a new hospital or OR. Even with the new problems, contrary to manufacturer’s claims equipment was not correctly positioned or integrated ORs, hospital staff are asked how about ease of use (for more discussion on not present at all; in the other 27 (55%), they want the OR designed or structured. this see section on medical devices used by the equipment malfunctioned as a result of Verdaasdonk (90) showed that a checklist patients). The possibility for design-induced a faulty connection (9), a defect (5), or the can reduce the number of incidents in human error was demonstrated, which is wrong setting of the equipment (3). In 10 the OR by more than 50%. Hence, when a strong argument for the importance of cases (20%) the exact cause of equipment medical devices are not intuitive to use (or human factors engineering. malfunctioning was unclear. standardized), other measures could be taken to ensure that no errors are made. Increasing complexity of medical technology and consequences for training and for outcome of care—Background paper 4 15

Evaluation of the surgical process

When laparoscopic or similar equipment requires extensive training and testing in parameters to describe the process, 3) is investigated, the current quality analysis simulators, before and after completion of defi ne quantitative measures to analyse is mostly restricted to the analysis of education. In the fi eld of surgery, similar correctness and effi cacy of the procedure the post-operative outcomes of patients analysis and training methods could be used (101-103), 4) record the peroperative process, in terms of morbidity, mortality, survival, to improve surgical outcomes. 5) analyse the peroperative process and more recently the analysis of learning in accordance with the aim (104-108), 6) curves (70). Standards exist for the design evaluate outcome and discuss detected phase of medical devices (Medical Device Peroperative task analysis problems in a multidisciplinary team, and Directives 93/42/EEC, prEN 1331, ISO Objective analysis of the surgical process 7) fi nd the solutions to the problems that 9000/IEC guide 51), but not for objectively and the devices used therein are even most negatively infl uenced the outcome evaluating the functionality of instruments more important now that the technological for the patient. during peroperative use (70,91,96). complexity of medical interventions is increasing. The Minimally Invasive Surgery Achieving the goals Aviation and production industries employ and Interventional Techniques group at A medical devices unit or organization detailed process analyses to determine the Delft University of Technology has could track the introduction of new devices the quality and effi cacy of the process. In developed a methodology to describe and and implement measures on training of industry, for example, human–machine analyse the surgical process (70,100). This complex medical device use. This unit or interactions are modelled; human errors or methodology consists of seven steps that organization could also take any necessary technological failures in complex production can be used to measure the correctness action to promptly protect the public if a processes are also analysed (10, 97–99). A and efficacy of task performance, problem is detected, and encourage health- similar methodology was developed by protocols and the instruments used care professionals and industry to discuss Sjoerdsma et al. to describe and analyse the (70): 1) defi ne the aim of the study (e.g. problems related to medical devices. surgical process (100). Aviation, for example, compare different procedures), 2) defi ne 16 Medical devices: managing the mismatch—An outcome of the Priority Medical Devices project

Conclusions

New technologies are entering medical 2) the user is often not trained properly to facilitated by a biomedical engineer or practice at an astounding pace. This is use these devices; and similar health-care professional. If the motivated in part by patients who request 3) the (new) procedures often result in long beneﬁ t of an instrument or device cannot (and increasingly expect) minimally learning curves for health professionals. be proven through these assessments, it invasive procedures that result in minimal should not be introduced. Standardization damage to healthy tissue. The ‘side- These three facts inﬂ uence outcome of of equipment can solve many user effects’ resulting from the introduction of care. It has been shown that it is valuable problems; indeed this measure has been new, often-complex technology in health to develop a standardized methodology used effectively by aviation and industry. care, however, can be considerable—both for the evaluation of the quality of medical Training and (continuing) education are for patients and health professionals. devices and the analysis of complications important components of standardization, resulting from their (mis)use. This can be to ensure safety. Any programmes This paper has shown the consequences done by introducing various methods, such standardizing medical practices and the of the increased complexity of technology as a video monitoring system. It is better use of medical devices could include used for the treatment of patients. Three that new equipment and instrumentation training curricula, including credentialing facts emerged: not be introduced without a thorough methods for the post-training period (e.g. 1) the devices are often not well designed evaluation of its functionality (Technical every half year). Implementing such for the medical environment in which Evaluation), followed by monitoring its measures as part of an overall programme they are used; use in clinical practice (Health Technology of standardization will help to reduce errors Assessment). These evaluations can be and improve care. Increasing complexity of medical technology and consequences for training and for outcome of care—Background paper 4 17

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