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An interactive multimedia training system for advanced cardiac life support
Computer Methods and Programs in Biomedicine 60 (1999) 117 – 131 www.elsevier.com/locate/cmpb
An interactive multimedia training system for advanced cardiac life support ZhongZhong Rebecca Xie a,1, Jacob Jen-Gwo Chen b,2, Richard W. Scamell c,*, Miguel A. Gonzalez d,3 a
Department of Industrial Engineering, Cullen College of Engineering, Uni6ersity of Houston, 4800 Calhoun Boule6ard, Houston, TX 77204, USA b College of Science and Engineering, The Uni6ersity of Texas-Pan American, 1201 West Uni6ersity Dri6e, Edinburg, TX 78539, USA c Department of Decision and Information Sciences, College of Business Administration, Uni6ersity of Houston, 4800 Calhoun Boule6ard, 280J Melcher Hall, Houston, TX 77204 -6282, USA d Manufacturing Engineering Program, College of Science and Engineering, The Uni6ersity of Texas-Pan American, 1201 West Uni6ersity Dri6e, Edinburg, TX 78539, USA Received 20 July 1998; received in revised form 18 February 1999; accepted 25 March 1999
Abstract This paper describes an Advanced cardiac life support (ACLS) training system (ACLSYS) with multimedia and hypertext features for training medical personnel and evaluating their performance during ACLS events. ACLSYS runs in a Windows 95 environment and is written in Visual Basic 4.0 Enterprise Edition and Access 7.0. The system consists of two primary modules: a multimedia training module and a simulation/evaluation module. The training module provides the knowledge and skills required for the appropriate early treatment of cardiopulmonary arrest. The simulation/evaluation module generates randomly an unlimited number of ACLS cases. These cases become part of the training case database and are available for retraining. ACLS certified personnel were included in the validation of the system. © 1999 Elsevier Science Ireland Ltd. All rights reserved. Keywords: Advanced cardiac life support; Multimedia training system; Simulation
1. Introduction * Corresponding author. Tel.: +1-713-7434733; fax: +1713-7434940. E-mail addresses: [email protected] (Z. Rebecca Xie), [email protected] (J. Jen-Gwo Chen), [email protected] (R.W. Scamell), [email protected] (M.A. Gonzalez) 1 Tel.: + 1-713-7434186; fax: + 1-713-4190. 2 Tel.: + 1-956-3812404; fax: + 1-956-3812428. 3 Tel.: + 1-956-3812673; fax: + 1-956-3813527.
Cardiac arrhythmia is a life-threatening event and a common highest-risk medical problem [1]. Since more than half of the deaths due to heart disease occur outside the hospital and most within 2 h of the onset of symptoms [2], it is necessary to educate the public to: (a) recognize life-threaten-
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ing emergencies quickly; (b) provide CPR promptly and appropriately; and (c) rapidly access available emergency response systems (e.g. 911). In recent years, a number of training programs have been created to provide this type of education. These include ACLS courses that have proven helpful to critical care practitioners and emergency medical technicians (EMTs). EMTs usually perform life-saving procedures outside the hospital in an effort to help patients survive until in-hospital care can be applied. On the other hand, in space flights, which attract world-wide attention, it is necessary to train one or more of the crew members as crew medical officers (CMOs) since emergency medical care may not be available in a manned mission into space should an instance of cardiac arrhythmia occur [3,4]. There are many ACLS training programs available. Most use written tests to evaluate performance in ACLS situations, or require testing in what is called a ‘hands on’ test or simulation [5]. As has been true in many fields, recently information technology is being used more and more in the ACLS training program. Eliot [6] built a simulation-based intelligent system for teaching medical personnel cardiac resuscitation skills using artificial intelligence and pedagogical techniques. The distinguishing aspects of this system include its ability: (a) to evaluate student comprehension and performance on more than 20 topics; and (b) to dynamically adjust the simulation to support the learning needs of the student. Yoon [4] developed a hypermedia expert database system for emergency medical assistance to help crew medical officers diagnose and treat cardiac arrhythmia on Space Station Freedom. The system serves as a supplemental tool for training the CMO in the protocols of ACLS management. A distinctive contribution of the system is the development of a mechanism that establishes the standard times for the ACLS protocols based on a predetermined time set obtained from a simulated microgravity environment. In 1995, Gonzalez [3] developed an integrated logistics support system for ACLS training. The system’s two major features are its integrated learning and forgetting model used to establish
CMO performance level and an evaluation and training tool used to provide an unlimited number of randomly generated simulation cases to analyze the trainee’s performance and decision making skills. There are several commercial software packages for ACLS training available today (e.g. Challenger Corporation’s Med-Challenger FP, Anesoft’s ACLS Simulator and Critical Care Simulator, and Mad Scientist Software’s Cardiac Arrest!). Cardiac Arrest!, a popular product developed by Bruce Argyle and his co-workers, offers the use of full-motion video, text and still images. Argyle’s package has two main problems: the number of patients (arrhythmia simulation cases) is limited and the lack of hypertext. Collectively, the currently available traditional text-based along with the newer computer-based ACLS training programs lack the capability to provide both randomized and customized arrhythmia cases for training, the capability to make the ACLS course materials more informative and help the trainee retain more as a result of interactive multimedia training [7,8], the capability to guarantee that the content and quality of courses is consistent at any time, the capability to provide the trainee with real sights, real sounds, and live-action video about ACLS knowledge and skills, and the capability to provide hypertext-based ACLS protocols and guidelines [9]. The objective of this paper is to describe a multimedia training system for ACLS that serves as a tool for training and evaluating the performance of out-of-hospital emergency medical technicians (EMTs) or other medical personnel in the knowledge and skills necessary to provide early treatment for cardiopulmonary arrest. The system is based on the Textbook of Advanced Cardiac Life Support [9] and ACLS protocols (or algorithms), and consists of two primary modules: a multimedia training module and a simulation/evaluation module. The purpose of the training module is to serve as a reference and supplement to an ACLS training course. Medical personnel can use it before, during, or after the training class to practice or obtain the knowledge and skills required for
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ACLS. Multimedia, in the form of audio, fullmotion and still image, and hypertext technologies, are applied in this task to enhance the ACLS training provided. The objective of the simulation/evaluation module is to evaluate the performance of the trained medical technicians in ACLS. It provides an unlimited number of arrhythmia patient cases for evaluation. A trainee may either choose a simulated arrhythmia case randomly generated by the system or a specified arrhythmia case. The module also offers both time-limited and time-unlimited simulation options. Typically the patient’s survival time is obtained when the simulation begins. The time-limited simulator is always used for evaluation under the stressful, real time conditions that the possible end of a patient’s life can bring while the time-unlimited simulator is used for the beginning trainee to learn the life-saving procedures by following the protocols step by step.
2. Multimedia and hypertext applications in medicine During the 1990s, multimedia has been used in a variety of ways to enhance medical training and learning. For example, Batschkus [10] employed imaging techniques and multimedia technologies to develop interactive multimedia software for training and education in neurosurgery in an effort to improve teaching and training. While great progress has been made in endonasal sinus surgery, learning the required surgical techniques remains difficult. An interactive training system with multimedia technology has been developed to diminish the complication rate [11]. This system improves the training in endonasal surgery and affords the visualized reproduction of difficult surgical steps as a basis for mastering them. Klinisches Monatsblatt in Augenheilkd (KMA) designed a computer-assisted multimedia interactive learning program in 1996 in Germany to provide access to all modes of information storage and retrieval as well as documentation and training systems within a specific context. Since the winter semester 1995,
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the Department of Ophthalmology in Giessen has used the learning program Primary Open Angle Glaucoma for student instruction. One factor that contributed to the implementation of this project was that actual training using patients within the clinic is difficult to conduct. Media-supported training that can provide a simulation of actual practice offers a suitable substitute. This program was developed using Hypercard software that provides a user-friendly graphical work environment. The glaucoma learning program is structured along the lines of anatomy and includes an explanation of the circulation of the aqueous humor, pathology, clinical symptoms and findings, diagnosis and treatment. The program is designed in such a way that working with and through it is done in a manner conducive to learning. Student response to the program as an accompaniment to instruction has been positive [10]. Hypertext offers a powerful way of organizing and accessing information. An information technology, it is rapidly reshaping the society in which we live by changing the way in which we read, write and organize information. Medical practitioners and researchers usually deal with huge amounts of information. It is necessary for them to cross-examine many facts and interpretations in order to make a correct diagnosis or reach a correct conclusion. Hypertext is able to improve the speed and accuracy of medical information management. The Dynamic Medical Handbook project developed at the Washington University School of Medicine in St. Louis is a hypertext form of the medical therapeutics manual [12]. As a diagnostic tool, its indexing and searching mechanisms constitute its major focus. The typical way of finding information in a hypertext database is by jumping from node to node via links. In contrast, the traditional method for searching in information retrieval systems is text string pattern matching. Many medical texts are well suited to hypertext and hypermedia applications. For example, at Johns Hopkins Hospital, a Drug Information database was designed to replace a variety of drug reference books used [11].
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Fig. 1. ACLSYS architecture.
3. System description The interactive multimedia ACLS training system (ACLSYS) described in this paper is designed as a supplement to train and evaluate the abilities of those who are required to perform ACLS. It can be used by ACLS instructors as part of their courses or by trainees before or after class as a
way to practice by themselves. ACLSYS runs in a Windows 95 environment, is written in Visual Basic 4.0 Enterprise Edition and Microsoft Access 7.0, and requires a Pentium machine with 16 megabytes of RAM, a built-in sound card, and a pair of speakers. Fig. 1 contains the architecture of the multimedia training system and illustrates the relationship
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between its modules and tasks. The purpose of the system is to: (a) enhance the effect of ACLS training with multimedia tools; (b) make the protocol procedures easy to conduct; and (c) make it possible for ACLS trainees to train and evaluate their performance on their own. As shown in Fig. 1, there are five modules in the system: a multimedia training module, a simulation/evaluation module, an evaluation report analysis module, an edit/update databases module, and a help module. Based on the guidelines that appear in the Textbook of Advanced Cardiac Life Support and the protocols of ACLS, the multimedia training module provides CPR tasks for basic life support (BLS) training, EKG recognition, arrhythmia symptom recognition, heart sound recognition, and equipment management for the use of defibrillators. The system also includes several databases and files: (a) the drug usage database, which stores information on cardiovascular pharmacology; (b) the training information database, which stores information for training tasks; (c) the evaluation log file, which records actions taken by the trainee during the simulation/evaluation; (d) the training case database, which stores different arrhythmia cases used by the trainees in the time-limited and time-unlimited simulations; and (e) the arrhythmia probability and survival time distributions used to generate simulation cases.
3.1. The multimedia training module for ad6anced cardiac life support The ACLSYS multimedia training module constitutes a basic reference of the knowledge and skills required by medical personnel to provide the appropriate early treatment for cardiopulmonary arrest. The ACLS training tasks in this module are: (1) description of the procedure for administering CPR; (2) arrhythmia definition and identification; (3) arrhythmia heart sound recognition; (4) identification of arrhythmia EKG patterns; (5) electrocardiogram (EKG) and defibrillator use; (6) intravenous (IV) access establishment; (7) drug information including usage, dosage, and precautions; and (8) information about ACLS protocols
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or algorithms, including ECC, VF/VT, PEA, Asystole, Bradycardia, Tachycardia, Electrical Cardioversion, Hypotension/Shock/Acute Pulmonary Edema, and Acute Myocardial Infarction. The training module consists of four groups: (a) the arrhythmia training group, which includes arrhythmia definition and identification, arrhythmia symptom and heart sound recognition, EKG pattern recognition, and EKG/Defibrillator Use; (b) CPR procedures; (c) ACLS protocols; and (d) drug and equipment information.
3.1.1. The arrhythmia training group The purpose of the arrhythmia training group is to help the trainee recognize and diagnose arrhythmia quickly and accurately. Fig. 2 shows various procedures associated with this training group. The arrhythmia training process begins with the trainee selecting the type of arrhythmia from the rhythm list in the training module window as shown in Fig. 3. Clicking the Activate EKG Display button allows the trainee to see animated EKG strips flow across the display. On the other hand, the Freeze EKG Display button shows a static EKG strip with a grid that can be used to estimate the number of heart beats per minute for the specific rhythm. On the right-hand side of the EKG screen in the training module window is the Defibrillator. When defibrillation therapy is applied, the trainee must set the defibrillator Discharge Mode to either Normal Discharge or Synchronized. After setting the discharge mode, the trainee must set the charge amount by clicking the left or right arrow below the ‘Charge Setting’ label (Fig. 3) that automatically displays the number of Joules to be delivered. Once the charge amount is established, the defibrillator is charged by enabling the ‘Charge’ radio button. The Arrhythmia button at the far right of the training module window provides knowledge of arrhythmia definition and recognition that includes a description of the natural characteristics of several different types of arrhythmia and their EKG criteria. All of these sources come from Textbook of Advanced Cardiac Life Support [9]. Clicking the Arrhythmia button or menu item on
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Fig. 2. Procedures included in the arrhythmia training group.
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Fig. 3. The training module window with arrhythmia information displayed.
the command button panel shown in Fig. 3 displays a window that allows the trainee to read the descriptions of the various rhythms by choosing the related items. For example, Fig. 4 shows the information about the normal sinus rhythm (NSR) after opening the Normal Sinus Rhythm window. The real heart sound of normal sinus rhythm can be heard by clicking the heart sound button that appears in the low-left-hand corner of the window. To resuscitate a cardiopulmonary arrest successfully, the type of the arrhythmia must be recognized quickly. Arrhythmia symptom and heart sound identification training serves as a reference and supplement to the EKG strips shown in Fig. 3. It helps emergency medical personnel make an accurate diagnosis and shortens the decision-making time for a successful resuscitation. Clicking the Symptom Recog. button in
the training module window causes the symptom list box of the related rhythm to appear. The symptom list box shown just below the center in Fig. 3 contains the symptoms of Sinus Tachycardia Type – 1 (B 150 beats/min). For instance, Sinus Tachycardia Type – 1 exhibits the following signs [3,9]: Cardiac Awareness Palpitations Heart appears to be ‘Racing’.
3.1.2. CPR procedures CPR and early defibrillation are the best methods to deal with sudden non-traumatic cardiac arrest. CPR is the basic life-saving skill in the Basic Life Support (BLS). Using ACLSYS, the trainee can learn about CPR by clicking the CPR button in the main training window shown in Fig. 3. The CPR procedures come from MedAccess Corporation, the Handbook for Emergency Medical Personnel [13] and the American Heart Association [9].
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Fig. 4. Normal sinus rhythm window.
Pressing the CPR button brings the trainee to the CPR procedure window shown in Fig. 5. By clicking on Perform cardiac compression, additional details including visual images for performing cardiac compressions can be obtained.
3.1.3. ACLS protocols (or algorithms) Advanced Cardiac Life Support (ACLS) algorithms constitute a set of guidelines established by the American Heart Association [14]. These guidelines and algorithms summarize information for Emergency Cardiac Care (ECC) and are used as an educational tool for ACLS training. The algorithms included in ACLSYS are: ECC Universal Algorithm, Asystole, Bradycardia, Ventricular Fibrillation/Pulseless Ventricular Tachycarida (VF/VT), Unstable Ventricular
Tachycardia, Atrial Fibrillation and Flutter, Paroxysmal SuproVentricular Tachycardia (PSVT), Stable Ventricular tachycardia (VT), Sinus Tachycardia, Hypotension/Shock /Acute Pulmonary Edema, and Acute Myocardial Infarction (AMI) [3,14]. The trainee can learn and review these algorithms by clicking the Protocols button or menu item in Fig. 3.
3.1.4. Drug and equipment information Basic CPR, defibrillation and proper airway management are the primary focus to the rescuer when a cardiac arrest occurs. Once these interventions have been initiated, emergency personnel begin an IV infusion and give medication. Drugs like lidocaine and bretylium are used to control heart rhythm and rate. Other
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Fig. 5. CPR procedure window.
drugs such as epinephrine and dopamine can improve cardiac output and blood pressure. Drug information including recommended usage, dosage, and precautions is incorporated into ACLSYS based on the cardiovascular pharmacology material in Textbook of Advanced Cardiac Life Support [9]. The content window for the drug information is obtained by clicking the Drug Info. button in the training module window (Fig. 3). In the Drug Info Content window, clicking each drug item allows the trainee to read the related detailed information. Equipment information includes defibrillator monitoring, along with defibrillation and pacing usage. Clicking the Equipment button in the training module window (Fig. 3) provides access to information about equipment as clicking the Drug Info. button in the training module window provides information about drugs.
3.2. The simulation/e6aluation module The purpose of the simulation/evaluation module is to help the trainee learn both how and when to apply CPR, EKG, and IV and also how to diagnose and treat the arrhythmia. It provides a time-unlimited simulator that beginning trainees can use to learn how to perform ACLS skills and make use of the ACLS algorithms in an effort to save the patient’s life. It is also designed to evaluate the performance of the trainees within a limited time period under stressful real time conditions. The simulation/evaluation module consists of an initialization task, an action task, and a help task. The initialization task generates a patient suffering from an arrhythmia and allows the trainee to choose the specific type of arrhythmia for training. The action task is used to evaluate the trainee’s knowledge and skills in the perfor-
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mance of a simulated life-saving event. The help task provides on-line information for CPR, Arrhythmia, and Protocols.
3.2.1. Initialization task The mechanism used to randomly generate a patient with arrhythmia is the key of the initialization task. Since the distribution for the occurrence of arrhythmia is unknown, it is assumed that the probability of occurrence of a certain arrhythmia is a random variable that follows a uniform distribution. This assumption was made by Gonzalez [3] based on published medical documentation and consultation with certified ACLS instructors and practitioners. A survey of medical experts was made by Gonzalez to obtain the uniform distribution parameters for each arrhythmia included in the system. This information, including the arrhythmia name and both the lowest and highest expected probabilities of arrhythmia occurrence, is stored in the Arrhythmia Probability Database. Based on these probabilities, a set of random numbers that follows a uniform distribution is generated and then used to generate the probabilities of arrhythmia that follow a normal distribution. The process concludes with the generation of another random number following a normal distribution which is used to determine which arrhythmia will be selected for simulation [3]. After the generation of an arrhythmia, the survival time parameter must also be generated. Like the arrhythmia, the survival time also follows a uniform distribution. Fig. 6 describes the logic of the initialization task. This task begins with a message box that asks the trainee to select the random (‘New Test’) or previously used arrhythmia case for training. Once a patient with an arrhythmia is generated, the symptoms for this arrhythmia are loaded from the Arrhythmia Symptom Database. At this point, the trainee must try to save the patient’s life within the survival time. During the process, the patient’s life can be prolonged if the trainee takes the correct ACLS actions; otherwise, the patient expires. 3.2.2. Action task Time is the critical factor in life-saving actions. Therefore, the two time control parameters, a
continuous clock and the elapsed time, are the most important elements of the simulation/evaluation module. The continuous clock updates the patient clock every second. The time elapsed can be categorized into decision time and action time. The action standard times required to perform ACLS operations were derived by Yoon using a motion and time study [4]. These action times are fixed in this system. The time control mechanism itself is based on the work done by Gonzalez [3]. The logic of the action task is summarized in Fig. 7. Changes in the status of a patient after an action is taken are stochastic in nature [3]. The use of the simulation/evaluation module is contingent on the trainee’s knowledge of ACLS protocols. After a patient with a cardiac arrhythmia problem is generated, the trainee is expected to take actions that will change the patient’s status with respect to the arrhythmia problem. In the ACLS action form shown in Fig. 8, the various actions required to assist the patient can be taken by clicking the mouse on the appropriate button. To make an initial diagnosis, the trainee must be able to assess the breathing, pulse, conscious-
Fig. 6. Logic of the initialization task.
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Fig. 7. Logic of the action task.
ness, and symptoms of the patient. The system provides necessary information for making a diagnosis and designating a treatment. The assess symptoms form (Fig. 9) shows all of the patient’s symptoms and vital signs, an up-to-date inventory of the ACLS pack4, and an ACLS efforts report. To review this information, the trainee must activate the Access Symptoms button on the ACLS Action Form (Fig. 8). Once the Retrieve ACLS Pack button is activated, additional information about the inventory of medication appears at the bottom of the ACLS Action Form (Fig. 8). It should be mentioned that a number of actions (e.g. establish IV, EKG) can not be activated until the Retrieve ACLS Pack button is activated. Two of the most important actions during an ACLS event after assessing the patient’s symptoms are the IV establishment and 4 The ACLS Pack contains information about the drugs and equipment available for treating a patient.
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the EKG attachment. The EKG attachment that appears in the upper left hand corner of the ACLS Action Form allows the trainee to apply defibrillation therapy and EKG heart rate analysis. To use the EKG, the trainee must first retrieve the ACLS pack, and then attach the EKG by clicking the Adjust EKG Leads button in Fig. 8. After finishing the attachment of the EKG leads, the trainee can activate the EKG display. Fig. 8 illustrates the action form after retrieving the ACLS pack and activating the EKG/Defibrillator. IV access allows the trainee to administer drugs. When the Establish IV button (Fig. 8) is selected, an IV access form appears. At this point, the trainee selects a site on which to establish the IV access from a menu of IV establishment sites, which includes the right arm, left arm, right leg, left leg, and neck. Once the IV access has been established, the trainee can administer IV medications. The Cease Life Support button stops the simulator and brings the trainee back to the main window of the system. Prior to returning to the main window, the trainee is given the option of saving a record of the actions taken to treat the patient on the evaluation log file.
3.3. Other modules ACLSYS consists of three other modules: the Evaluation Report Analysis Module, the Edit/Update Databases Module, and the Help Function Module. The Evaluation Report Module is used to help the trainee evaluate his or her performance during simulated life-saving events. Using this information, the trainee is able to identify areas where improvement/retraining is required. The system also allows the trainee some limited editing and updating of databases. For example, through the Edit/Update Databases Module, the trainee is able to make changes to an existing training case (e.g. to the type of arrhythmia, survival time of the patient) and then re-enter the simulation/evaluation module for retraining. Online help is provided in ACLSYS through the application of hypertext. Help information includes help on system use as well as material from the Textbook of Advanced Cardiac Life Support and ACLS protocols.
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Fig. 8. ACLS action form after ACLS pack is retrieved and EKG/Defibrillator is activated.
4. Some concluding remarks Three questionnaires were completed by ACLS certified personnel and users in an effort to validate ACLSYS: one questionnaire for the training module, a second questionnaire for the simulation/evaluation module, and a third questionnaire aimed at the quality of the user interface for the entire system. The expert group included ACLScertified physicians from The University of Texas, Health Science Center and the Texas Heart Institute, while the user group contained students from the University of Houston, Department of Industrial Engineering (only for the evaluation of the user interface). Each question asked the evaluators to provide their degree of agreement or disagreement with a particular statement on a scale of 1 – 6:
Strongly Agree Sort of Sort of Disagree Strongly agree agree disagree disagree 6 5 4 3 2 1
The three questionnaires contain 13, 15, and 10 questions respectively about the topics given in the Appendix and generated overall average responses of 5.6538, 5.6667, and 5.833. Collectively, these questions attempt to measure what functions are met by the system and to what extent improvements might be made. Respondents were asked to provide comments when appropriate. Although ACLSYS serves as a reference and supplement for ACLS education, it can not replace the instructor of an ACLS course. In addition, while the system is designed to train and test
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Fig. 9. Access symptoms form.
individual performance in ACLS events, it does not test the trainee’s skill as a team leader. Possible extensions of the system include its application to training and simulation in related medical fields, such as trauma life support and respiratory system problems.
4
5
Questionnaire about the training module No. 1
2
3
Question For training purposes, the system provides useful and enough information regarding the procedures for CPR. For training purposes, the system provides useful information regarding ACLS protocols (or algorithms) including Emergency Cardiac Care. For training and reference purposes, the system provides useful information regarding the symptoms of various arrhythmia, which help the trainee learn to recognize different arrhythmia.
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8
9
For training and reference purposes, the arrhythmia EKG strips that are accessible in the system provide useful information to help the trainee learn to recognize various arrhythmia. For reference purposes, the system provides useful information regarding the use of medications. For reference purposes, the system provides useful information regarding the real heart sound. For training and reference purposes, the system provides useful information regarding the definition of arrhythmia. For reference purposes, the system provides useful information regarding the procedure and operation of an EKG/ defibrillator. For reference purposes, the system provides useful information regarding the procedure for defibrillator monitoring.
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9
10
11
12
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For reference purposes, the system provides useful information regarding the procedure for defibrillator monitoring. For reference purposes, the system provides useful information regarding the procedure for pacing. For system maintenance purposes, the system makes it easy to update the training information. In general, the information in the training module provides a useful reference for ACLS trainees. In general, the information provided in the training module should help develop the trainee’s ACLS knowledge.
Questionnaire about the simulation/evaluation module No. 1 2
3
4
5
6
7 8 9
10
Question In general, the system tests the trainee’s skill in arrhythmia recognition. In general, the system tests the trainee’s knowledge of how to treat various arrhythmia. The system tests the trainee’s skill in how to follow ACLS protocols in the life-saving procedure. The system tests the trainee in his/her ability to recognize arrhythmia from EKG strips. The system tests the trainee in his/her ability to treat a patient using defibrillation. The system tests the trainee in his/her ability to treat a patient using medicines (e.g., epinephrine, lidocaine). The system tests the trainee in his/her ability to treat a patient using oxygen. The system tests the trainee’s ability to determine when CPR is required. For training purposes, the simulation module provides a useful means to practice and develop ACLS protocol knowledge. The simulation option provides the trainee with useful practice to develop decision making skills.
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12
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Using the evaluation log file in general, it is possible to determine whether the trainee’s knowledge of ACLS protocols to treat different ACLS events is good, fair, or bad. Using the evaluation log file, it is possible to determine whether the trainee recognized arrhythmia correctly. Using the evaluation log file, it is possible to determine whether the trainee uses medications in the correct sequence. The evaluation log file can help the instructor or the trainee determine how and what to do with respect to retraining. The simulation module with the on-line help can help the beginner learn how to follow the ACLS protocols to save a patient’s life.
Questionnaire about the user interface No. 1 2
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5 6
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Question In general, the user interface of this system is user-friendly and easy to use. In the training module, the use of hypertext and multimedia enhances the training effect. The information provided in the simulation/evaluation module is sufficient to make decisions during the ACLS events. The information provided in the evaluation module is displayed in such a way as to make it possible to evaluate the trainee’s ability to make decisions and to follow protocols. The information recorded in the evaluation log files is presented properly. The information reported in the evaluation log files is sufficient to evaluate the trainee’s ability to follow protocols. The information reported in the evaluation log files is sufficient to evaluate the trainee’s ability to make pertinent decisions during ACLS events.
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8
9
10
In general, the interactive multimedia ACLS training system provides a useful tool for ACLS education. The arrhythmia cases presented in the simulation/evaluation module are realistic considering the simplifications that must be made for the use of computer simulation. The information provided in the training module is properly displayed and easy to use for the purpose of providing training and reference information.
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An interactive multimedia training system for advanced cardiac life support ZhongZhong Rebecca Xie a,1, Jacob Jen-Gwo Chen b,2, Richard W. Scamell c,*, Miguel A. Gonzalez d,3 a
Department of Industrial Engineering, Cullen College of Engineering, Uni6ersity of Houston, 4800 Calhoun Boule6ard, Houston, TX 77204, USA b College of Science and Engineering, The Uni6ersity of Texas-Pan American, 1201 West Uni6ersity Dri6e, Edinburg, TX 78539, USA c Department of Decision and Information Sciences, College of Business Administration, Uni6ersity of Houston, 4800 Calhoun Boule6ard, 280J Melcher Hall, Houston, TX 77204 -6282, USA d Manufacturing Engineering Program, College of Science and Engineering, The Uni6ersity of Texas-Pan American, 1201 West Uni6ersity Dri6e, Edinburg, TX 78539, USA Received 20 July 1998; received in revised form 18 February 1999; accepted 25 March 1999
Abstract This paper describes an Advanced cardiac life support (ACLS) training system (ACLSYS) with multimedia and hypertext features for training medical personnel and evaluating their performance during ACLS events. ACLSYS runs in a Windows 95 environment and is written in Visual Basic 4.0 Enterprise Edition and Access 7.0. The system consists of two primary modules: a multimedia training module and a simulation/evaluation module. The training module provides the knowledge and skills required for the appropriate early treatment of cardiopulmonary arrest. The simulation/evaluation module generates randomly an unlimited number of ACLS cases. These cases become part of the training case database and are available for retraining. ACLS certified personnel were included in the validation of the system. © 1999 Elsevier Science Ireland Ltd. All rights reserved. Keywords: Advanced cardiac life support; Multimedia training system; Simulation
1. Introduction * Corresponding author. Tel.: +1-713-7434733; fax: +1713-7434940. E-mail addresses: [email protected] (Z. Rebecca Xie), [email protected] (J. Jen-Gwo Chen), [email protected] (R.W. Scamell), [email protected] (M.A. Gonzalez) 1 Tel.: + 1-713-7434186; fax: + 1-713-4190. 2 Tel.: + 1-956-3812404; fax: + 1-956-3812428. 3 Tel.: + 1-956-3812673; fax: + 1-956-3813527.
Cardiac arrhythmia is a life-threatening event and a common highest-risk medical problem [1]. Since more than half of the deaths due to heart disease occur outside the hospital and most within 2 h of the onset of symptoms [2], it is necessary to educate the public to: (a) recognize life-threaten-
0169-2607/99/$ - see front matter © 1999 Elsevier Science Ireland Ltd. All rights reserved. PII: S 0 1 6 9 - 2 6 0 7 ( 9 9 ) 0 0 0 1 5 - 2
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ing emergencies quickly; (b) provide CPR promptly and appropriately; and (c) rapidly access available emergency response systems (e.g. 911). In recent years, a number of training programs have been created to provide this type of education. These include ACLS courses that have proven helpful to critical care practitioners and emergency medical technicians (EMTs). EMTs usually perform life-saving procedures outside the hospital in an effort to help patients survive until in-hospital care can be applied. On the other hand, in space flights, which attract world-wide attention, it is necessary to train one or more of the crew members as crew medical officers (CMOs) since emergency medical care may not be available in a manned mission into space should an instance of cardiac arrhythmia occur [3,4]. There are many ACLS training programs available. Most use written tests to evaluate performance in ACLS situations, or require testing in what is called a ‘hands on’ test or simulation [5]. As has been true in many fields, recently information technology is being used more and more in the ACLS training program. Eliot [6] built a simulation-based intelligent system for teaching medical personnel cardiac resuscitation skills using artificial intelligence and pedagogical techniques. The distinguishing aspects of this system include its ability: (a) to evaluate student comprehension and performance on more than 20 topics; and (b) to dynamically adjust the simulation to support the learning needs of the student. Yoon [4] developed a hypermedia expert database system for emergency medical assistance to help crew medical officers diagnose and treat cardiac arrhythmia on Space Station Freedom. The system serves as a supplemental tool for training the CMO in the protocols of ACLS management. A distinctive contribution of the system is the development of a mechanism that establishes the standard times for the ACLS protocols based on a predetermined time set obtained from a simulated microgravity environment. In 1995, Gonzalez [3] developed an integrated logistics support system for ACLS training. The system’s two major features are its integrated learning and forgetting model used to establish
CMO performance level and an evaluation and training tool used to provide an unlimited number of randomly generated simulation cases to analyze the trainee’s performance and decision making skills. There are several commercial software packages for ACLS training available today (e.g. Challenger Corporation’s Med-Challenger FP, Anesoft’s ACLS Simulator and Critical Care Simulator, and Mad Scientist Software’s Cardiac Arrest!). Cardiac Arrest!, a popular product developed by Bruce Argyle and his co-workers, offers the use of full-motion video, text and still images. Argyle’s package has two main problems: the number of patients (arrhythmia simulation cases) is limited and the lack of hypertext. Collectively, the currently available traditional text-based along with the newer computer-based ACLS training programs lack the capability to provide both randomized and customized arrhythmia cases for training, the capability to make the ACLS course materials more informative and help the trainee retain more as a result of interactive multimedia training [7,8], the capability to guarantee that the content and quality of courses is consistent at any time, the capability to provide the trainee with real sights, real sounds, and live-action video about ACLS knowledge and skills, and the capability to provide hypertext-based ACLS protocols and guidelines [9]. The objective of this paper is to describe a multimedia training system for ACLS that serves as a tool for training and evaluating the performance of out-of-hospital emergency medical technicians (EMTs) or other medical personnel in the knowledge and skills necessary to provide early treatment for cardiopulmonary arrest. The system is based on the Textbook of Advanced Cardiac Life Support [9] and ACLS protocols (or algorithms), and consists of two primary modules: a multimedia training module and a simulation/evaluation module. The purpose of the training module is to serve as a reference and supplement to an ACLS training course. Medical personnel can use it before, during, or after the training class to practice or obtain the knowledge and skills required for
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ACLS. Multimedia, in the form of audio, fullmotion and still image, and hypertext technologies, are applied in this task to enhance the ACLS training provided. The objective of the simulation/evaluation module is to evaluate the performance of the trained medical technicians in ACLS. It provides an unlimited number of arrhythmia patient cases for evaluation. A trainee may either choose a simulated arrhythmia case randomly generated by the system or a specified arrhythmia case. The module also offers both time-limited and time-unlimited simulation options. Typically the patient’s survival time is obtained when the simulation begins. The time-limited simulator is always used for evaluation under the stressful, real time conditions that the possible end of a patient’s life can bring while the time-unlimited simulator is used for the beginning trainee to learn the life-saving procedures by following the protocols step by step.
2. Multimedia and hypertext applications in medicine During the 1990s, multimedia has been used in a variety of ways to enhance medical training and learning. For example, Batschkus [10] employed imaging techniques and multimedia technologies to develop interactive multimedia software for training and education in neurosurgery in an effort to improve teaching and training. While great progress has been made in endonasal sinus surgery, learning the required surgical techniques remains difficult. An interactive training system with multimedia technology has been developed to diminish the complication rate [11]. This system improves the training in endonasal surgery and affords the visualized reproduction of difficult surgical steps as a basis for mastering them. Klinisches Monatsblatt in Augenheilkd (KMA) designed a computer-assisted multimedia interactive learning program in 1996 in Germany to provide access to all modes of information storage and retrieval as well as documentation and training systems within a specific context. Since the winter semester 1995,
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the Department of Ophthalmology in Giessen has used the learning program Primary Open Angle Glaucoma for student instruction. One factor that contributed to the implementation of this project was that actual training using patients within the clinic is difficult to conduct. Media-supported training that can provide a simulation of actual practice offers a suitable substitute. This program was developed using Hypercard software that provides a user-friendly graphical work environment. The glaucoma learning program is structured along the lines of anatomy and includes an explanation of the circulation of the aqueous humor, pathology, clinical symptoms and findings, diagnosis and treatment. The program is designed in such a way that working with and through it is done in a manner conducive to learning. Student response to the program as an accompaniment to instruction has been positive [10]. Hypertext offers a powerful way of organizing and accessing information. An information technology, it is rapidly reshaping the society in which we live by changing the way in which we read, write and organize information. Medical practitioners and researchers usually deal with huge amounts of information. It is necessary for them to cross-examine many facts and interpretations in order to make a correct diagnosis or reach a correct conclusion. Hypertext is able to improve the speed and accuracy of medical information management. The Dynamic Medical Handbook project developed at the Washington University School of Medicine in St. Louis is a hypertext form of the medical therapeutics manual [12]. As a diagnostic tool, its indexing and searching mechanisms constitute its major focus. The typical way of finding information in a hypertext database is by jumping from node to node via links. In contrast, the traditional method for searching in information retrieval systems is text string pattern matching. Many medical texts are well suited to hypertext and hypermedia applications. For example, at Johns Hopkins Hospital, a Drug Information database was designed to replace a variety of drug reference books used [11].
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Fig. 1. ACLSYS architecture.
3. System description The interactive multimedia ACLS training system (ACLSYS) described in this paper is designed as a supplement to train and evaluate the abilities of those who are required to perform ACLS. It can be used by ACLS instructors as part of their courses or by trainees before or after class as a
way to practice by themselves. ACLSYS runs in a Windows 95 environment, is written in Visual Basic 4.0 Enterprise Edition and Microsoft Access 7.0, and requires a Pentium machine with 16 megabytes of RAM, a built-in sound card, and a pair of speakers. Fig. 1 contains the architecture of the multimedia training system and illustrates the relationship
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between its modules and tasks. The purpose of the system is to: (a) enhance the effect of ACLS training with multimedia tools; (b) make the protocol procedures easy to conduct; and (c) make it possible for ACLS trainees to train and evaluate their performance on their own. As shown in Fig. 1, there are five modules in the system: a multimedia training module, a simulation/evaluation module, an evaluation report analysis module, an edit/update databases module, and a help module. Based on the guidelines that appear in the Textbook of Advanced Cardiac Life Support and the protocols of ACLS, the multimedia training module provides CPR tasks for basic life support (BLS) training, EKG recognition, arrhythmia symptom recognition, heart sound recognition, and equipment management for the use of defibrillators. The system also includes several databases and files: (a) the drug usage database, which stores information on cardiovascular pharmacology; (b) the training information database, which stores information for training tasks; (c) the evaluation log file, which records actions taken by the trainee during the simulation/evaluation; (d) the training case database, which stores different arrhythmia cases used by the trainees in the time-limited and time-unlimited simulations; and (e) the arrhythmia probability and survival time distributions used to generate simulation cases.
3.1. The multimedia training module for ad6anced cardiac life support The ACLSYS multimedia training module constitutes a basic reference of the knowledge and skills required by medical personnel to provide the appropriate early treatment for cardiopulmonary arrest. The ACLS training tasks in this module are: (1) description of the procedure for administering CPR; (2) arrhythmia definition and identification; (3) arrhythmia heart sound recognition; (4) identification of arrhythmia EKG patterns; (5) electrocardiogram (EKG) and defibrillator use; (6) intravenous (IV) access establishment; (7) drug information including usage, dosage, and precautions; and (8) information about ACLS protocols
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or algorithms, including ECC, VF/VT, PEA, Asystole, Bradycardia, Tachycardia, Electrical Cardioversion, Hypotension/Shock/Acute Pulmonary Edema, and Acute Myocardial Infarction. The training module consists of four groups: (a) the arrhythmia training group, which includes arrhythmia definition and identification, arrhythmia symptom and heart sound recognition, EKG pattern recognition, and EKG/Defibrillator Use; (b) CPR procedures; (c) ACLS protocols; and (d) drug and equipment information.
3.1.1. The arrhythmia training group The purpose of the arrhythmia training group is to help the trainee recognize and diagnose arrhythmia quickly and accurately. Fig. 2 shows various procedures associated with this training group. The arrhythmia training process begins with the trainee selecting the type of arrhythmia from the rhythm list in the training module window as shown in Fig. 3. Clicking the Activate EKG Display button allows the trainee to see animated EKG strips flow across the display. On the other hand, the Freeze EKG Display button shows a static EKG strip with a grid that can be used to estimate the number of heart beats per minute for the specific rhythm. On the right-hand side of the EKG screen in the training module window is the Defibrillator. When defibrillation therapy is applied, the trainee must set the defibrillator Discharge Mode to either Normal Discharge or Synchronized. After setting the discharge mode, the trainee must set the charge amount by clicking the left or right arrow below the ‘Charge Setting’ label (Fig. 3) that automatically displays the number of Joules to be delivered. Once the charge amount is established, the defibrillator is charged by enabling the ‘Charge’ radio button. The Arrhythmia button at the far right of the training module window provides knowledge of arrhythmia definition and recognition that includes a description of the natural characteristics of several different types of arrhythmia and their EKG criteria. All of these sources come from Textbook of Advanced Cardiac Life Support [9]. Clicking the Arrhythmia button or menu item on
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Fig. 2. Procedures included in the arrhythmia training group.
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Fig. 3. The training module window with arrhythmia information displayed.
the command button panel shown in Fig. 3 displays a window that allows the trainee to read the descriptions of the various rhythms by choosing the related items. For example, Fig. 4 shows the information about the normal sinus rhythm (NSR) after opening the Normal Sinus Rhythm window. The real heart sound of normal sinus rhythm can be heard by clicking the heart sound button that appears in the low-left-hand corner of the window. To resuscitate a cardiopulmonary arrest successfully, the type of the arrhythmia must be recognized quickly. Arrhythmia symptom and heart sound identification training serves as a reference and supplement to the EKG strips shown in Fig. 3. It helps emergency medical personnel make an accurate diagnosis and shortens the decision-making time for a successful resuscitation. Clicking the Symptom Recog. button in
the training module window causes the symptom list box of the related rhythm to appear. The symptom list box shown just below the center in Fig. 3 contains the symptoms of Sinus Tachycardia Type – 1 (B 150 beats/min). For instance, Sinus Tachycardia Type – 1 exhibits the following signs [3,9]: Cardiac Awareness Palpitations Heart appears to be ‘Racing’.
3.1.2. CPR procedures CPR and early defibrillation are the best methods to deal with sudden non-traumatic cardiac arrest. CPR is the basic life-saving skill in the Basic Life Support (BLS). Using ACLSYS, the trainee can learn about CPR by clicking the CPR button in the main training window shown in Fig. 3. The CPR procedures come from MedAccess Corporation, the Handbook for Emergency Medical Personnel [13] and the American Heart Association [9].
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Fig. 4. Normal sinus rhythm window.
Pressing the CPR button brings the trainee to the CPR procedure window shown in Fig. 5. By clicking on Perform cardiac compression, additional details including visual images for performing cardiac compressions can be obtained.
3.1.3. ACLS protocols (or algorithms) Advanced Cardiac Life Support (ACLS) algorithms constitute a set of guidelines established by the American Heart Association [14]. These guidelines and algorithms summarize information for Emergency Cardiac Care (ECC) and are used as an educational tool for ACLS training. The algorithms included in ACLSYS are: ECC Universal Algorithm, Asystole, Bradycardia, Ventricular Fibrillation/Pulseless Ventricular Tachycarida (VF/VT), Unstable Ventricular
Tachycardia, Atrial Fibrillation and Flutter, Paroxysmal SuproVentricular Tachycardia (PSVT), Stable Ventricular tachycardia (VT), Sinus Tachycardia, Hypotension/Shock /Acute Pulmonary Edema, and Acute Myocardial Infarction (AMI) [3,14]. The trainee can learn and review these algorithms by clicking the Protocols button or menu item in Fig. 3.
3.1.4. Drug and equipment information Basic CPR, defibrillation and proper airway management are the primary focus to the rescuer when a cardiac arrest occurs. Once these interventions have been initiated, emergency personnel begin an IV infusion and give medication. Drugs like lidocaine and bretylium are used to control heart rhythm and rate. Other
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Fig. 5. CPR procedure window.
drugs such as epinephrine and dopamine can improve cardiac output and blood pressure. Drug information including recommended usage, dosage, and precautions is incorporated into ACLSYS based on the cardiovascular pharmacology material in Textbook of Advanced Cardiac Life Support [9]. The content window for the drug information is obtained by clicking the Drug Info. button in the training module window (Fig. 3). In the Drug Info Content window, clicking each drug item allows the trainee to read the related detailed information. Equipment information includes defibrillator monitoring, along with defibrillation and pacing usage. Clicking the Equipment button in the training module window (Fig. 3) provides access to information about equipment as clicking the Drug Info. button in the training module window provides information about drugs.
3.2. The simulation/e6aluation module The purpose of the simulation/evaluation module is to help the trainee learn both how and when to apply CPR, EKG, and IV and also how to diagnose and treat the arrhythmia. It provides a time-unlimited simulator that beginning trainees can use to learn how to perform ACLS skills and make use of the ACLS algorithms in an effort to save the patient’s life. It is also designed to evaluate the performance of the trainees within a limited time period under stressful real time conditions. The simulation/evaluation module consists of an initialization task, an action task, and a help task. The initialization task generates a patient suffering from an arrhythmia and allows the trainee to choose the specific type of arrhythmia for training. The action task is used to evaluate the trainee’s knowledge and skills in the perfor-
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mance of a simulated life-saving event. The help task provides on-line information for CPR, Arrhythmia, and Protocols.
3.2.1. Initialization task The mechanism used to randomly generate a patient with arrhythmia is the key of the initialization task. Since the distribution for the occurrence of arrhythmia is unknown, it is assumed that the probability of occurrence of a certain arrhythmia is a random variable that follows a uniform distribution. This assumption was made by Gonzalez [3] based on published medical documentation and consultation with certified ACLS instructors and practitioners. A survey of medical experts was made by Gonzalez to obtain the uniform distribution parameters for each arrhythmia included in the system. This information, including the arrhythmia name and both the lowest and highest expected probabilities of arrhythmia occurrence, is stored in the Arrhythmia Probability Database. Based on these probabilities, a set of random numbers that follows a uniform distribution is generated and then used to generate the probabilities of arrhythmia that follow a normal distribution. The process concludes with the generation of another random number following a normal distribution which is used to determine which arrhythmia will be selected for simulation [3]. After the generation of an arrhythmia, the survival time parameter must also be generated. Like the arrhythmia, the survival time also follows a uniform distribution. Fig. 6 describes the logic of the initialization task. This task begins with a message box that asks the trainee to select the random (‘New Test’) or previously used arrhythmia case for training. Once a patient with an arrhythmia is generated, the symptoms for this arrhythmia are loaded from the Arrhythmia Symptom Database. At this point, the trainee must try to save the patient’s life within the survival time. During the process, the patient’s life can be prolonged if the trainee takes the correct ACLS actions; otherwise, the patient expires. 3.2.2. Action task Time is the critical factor in life-saving actions. Therefore, the two time control parameters, a
continuous clock and the elapsed time, are the most important elements of the simulation/evaluation module. The continuous clock updates the patient clock every second. The time elapsed can be categorized into decision time and action time. The action standard times required to perform ACLS operations were derived by Yoon using a motion and time study [4]. These action times are fixed in this system. The time control mechanism itself is based on the work done by Gonzalez [3]. The logic of the action task is summarized in Fig. 7. Changes in the status of a patient after an action is taken are stochastic in nature [3]. The use of the simulation/evaluation module is contingent on the trainee’s knowledge of ACLS protocols. After a patient with a cardiac arrhythmia problem is generated, the trainee is expected to take actions that will change the patient’s status with respect to the arrhythmia problem. In the ACLS action form shown in Fig. 8, the various actions required to assist the patient can be taken by clicking the mouse on the appropriate button. To make an initial diagnosis, the trainee must be able to assess the breathing, pulse, conscious-
Fig. 6. Logic of the initialization task.
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Fig. 7. Logic of the action task.
ness, and symptoms of the patient. The system provides necessary information for making a diagnosis and designating a treatment. The assess symptoms form (Fig. 9) shows all of the patient’s symptoms and vital signs, an up-to-date inventory of the ACLS pack4, and an ACLS efforts report. To review this information, the trainee must activate the Access Symptoms button on the ACLS Action Form (Fig. 8). Once the Retrieve ACLS Pack button is activated, additional information about the inventory of medication appears at the bottom of the ACLS Action Form (Fig. 8). It should be mentioned that a number of actions (e.g. establish IV, EKG) can not be activated until the Retrieve ACLS Pack button is activated. Two of the most important actions during an ACLS event after assessing the patient’s symptoms are the IV establishment and 4 The ACLS Pack contains information about the drugs and equipment available for treating a patient.
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the EKG attachment. The EKG attachment that appears in the upper left hand corner of the ACLS Action Form allows the trainee to apply defibrillation therapy and EKG heart rate analysis. To use the EKG, the trainee must first retrieve the ACLS pack, and then attach the EKG by clicking the Adjust EKG Leads button in Fig. 8. After finishing the attachment of the EKG leads, the trainee can activate the EKG display. Fig. 8 illustrates the action form after retrieving the ACLS pack and activating the EKG/Defibrillator. IV access allows the trainee to administer drugs. When the Establish IV button (Fig. 8) is selected, an IV access form appears. At this point, the trainee selects a site on which to establish the IV access from a menu of IV establishment sites, which includes the right arm, left arm, right leg, left leg, and neck. Once the IV access has been established, the trainee can administer IV medications. The Cease Life Support button stops the simulator and brings the trainee back to the main window of the system. Prior to returning to the main window, the trainee is given the option of saving a record of the actions taken to treat the patient on the evaluation log file.
3.3. Other modules ACLSYS consists of three other modules: the Evaluation Report Analysis Module, the Edit/Update Databases Module, and the Help Function Module. The Evaluation Report Module is used to help the trainee evaluate his or her performance during simulated life-saving events. Using this information, the trainee is able to identify areas where improvement/retraining is required. The system also allows the trainee some limited editing and updating of databases. For example, through the Edit/Update Databases Module, the trainee is able to make changes to an existing training case (e.g. to the type of arrhythmia, survival time of the patient) and then re-enter the simulation/evaluation module for retraining. Online help is provided in ACLSYS through the application of hypertext. Help information includes help on system use as well as material from the Textbook of Advanced Cardiac Life Support and ACLS protocols.
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Fig. 8. ACLS action form after ACLS pack is retrieved and EKG/Defibrillator is activated.
4. Some concluding remarks Three questionnaires were completed by ACLS certified personnel and users in an effort to validate ACLSYS: one questionnaire for the training module, a second questionnaire for the simulation/evaluation module, and a third questionnaire aimed at the quality of the user interface for the entire system. The expert group included ACLScertified physicians from The University of Texas, Health Science Center and the Texas Heart Institute, while the user group contained students from the University of Houston, Department of Industrial Engineering (only for the evaluation of the user interface). Each question asked the evaluators to provide their degree of agreement or disagreement with a particular statement on a scale of 1 – 6:
Strongly Agree Sort of Sort of Disagree Strongly agree agree disagree disagree 6 5 4 3 2 1
The three questionnaires contain 13, 15, and 10 questions respectively about the topics given in the Appendix and generated overall average responses of 5.6538, 5.6667, and 5.833. Collectively, these questions attempt to measure what functions are met by the system and to what extent improvements might be made. Respondents were asked to provide comments when appropriate. Although ACLSYS serves as a reference and supplement for ACLS education, it can not replace the instructor of an ACLS course. In addition, while the system is designed to train and test
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Fig. 9. Access symptoms form.
individual performance in ACLS events, it does not test the trainee’s skill as a team leader. Possible extensions of the system include its application to training and simulation in related medical fields, such as trauma life support and respiratory system problems.
4
5
Questionnaire about the training module No. 1
2
3
Question For training purposes, the system provides useful and enough information regarding the procedures for CPR. For training purposes, the system provides useful information regarding ACLS protocols (or algorithms) including Emergency Cardiac Care. For training and reference purposes, the system provides useful information regarding the symptoms of various arrhythmia, which help the trainee learn to recognize different arrhythmia.
6
7
8
9
For training and reference purposes, the arrhythmia EKG strips that are accessible in the system provide useful information to help the trainee learn to recognize various arrhythmia. For reference purposes, the system provides useful information regarding the use of medications. For reference purposes, the system provides useful information regarding the real heart sound. For training and reference purposes, the system provides useful information regarding the definition of arrhythmia. For reference purposes, the system provides useful information regarding the procedure and operation of an EKG/ defibrillator. For reference purposes, the system provides useful information regarding the procedure for defibrillator monitoring.
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9
10
11
12
13
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For reference purposes, the system provides useful information regarding the procedure for defibrillator monitoring. For reference purposes, the system provides useful information regarding the procedure for pacing. For system maintenance purposes, the system makes it easy to update the training information. In general, the information in the training module provides a useful reference for ACLS trainees. In general, the information provided in the training module should help develop the trainee’s ACLS knowledge.
Questionnaire about the simulation/evaluation module No. 1 2
3
4
5
6
7 8 9
10
Question In general, the system tests the trainee’s skill in arrhythmia recognition. In general, the system tests the trainee’s knowledge of how to treat various arrhythmia. The system tests the trainee’s skill in how to follow ACLS protocols in the life-saving procedure. The system tests the trainee in his/her ability to recognize arrhythmia from EKG strips. The system tests the trainee in his/her ability to treat a patient using defibrillation. The system tests the trainee in his/her ability to treat a patient using medicines (e.g., epinephrine, lidocaine). The system tests the trainee in his/her ability to treat a patient using oxygen. The system tests the trainee’s ability to determine when CPR is required. For training purposes, the simulation module provides a useful means to practice and develop ACLS protocol knowledge. The simulation option provides the trainee with useful practice to develop decision making skills.
11
12
13
14
15
Using the evaluation log file in general, it is possible to determine whether the trainee’s knowledge of ACLS protocols to treat different ACLS events is good, fair, or bad. Using the evaluation log file, it is possible to determine whether the trainee recognized arrhythmia correctly. Using the evaluation log file, it is possible to determine whether the trainee uses medications in the correct sequence. The evaluation log file can help the instructor or the trainee determine how and what to do with respect to retraining. The simulation module with the on-line help can help the beginner learn how to follow the ACLS protocols to save a patient’s life.
Questionnaire about the user interface No. 1 2
3
4
5 6
7
Question In general, the user interface of this system is user-friendly and easy to use. In the training module, the use of hypertext and multimedia enhances the training effect. The information provided in the simulation/evaluation module is sufficient to make decisions during the ACLS events. The information provided in the evaluation module is displayed in such a way as to make it possible to evaluate the trainee’s ability to make decisions and to follow protocols. The information recorded in the evaluation log files is presented properly. The information reported in the evaluation log files is sufficient to evaluate the trainee’s ability to follow protocols. The information reported in the evaluation log files is sufficient to evaluate the trainee’s ability to make pertinent decisions during ACLS events.
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8
9
10
In general, the interactive multimedia ACLS training system provides a useful tool for ACLS education. The arrhythmia cases presented in the simulation/evaluation module are realistic considering the simplifications that must be made for the use of computer simulation. The information provided in the training module is properly displayed and easy to use for the purpose of providing training and reference information.
References [1] B.R. Nelson, R. Gardner, D. Ostler, J. Logan, Medical Impact Analysis for the Space Station, NASA JSC 31013, Revision B, Life Sciences Division, July 24, 1984. [2] M. Newman, The chain of survival concept takes hold, Emerg. Med. Serv. 14 (1989) 11–13. [3] M. Gonzalez, An Integrated Logistics Support System for Training Crew Medical Officers on Advanced Cardiac Life Support, Doctoral Dissertation, University of Houston, Department of Industrial Engineering, Houston, TX, 1995. [4] H.S. Yoon, A Hypermedia Expert Database System For Emergency Medical Assistance, Doctoral Dissertation,
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