Safety and Traceability in Patient Healthcare Through the Integration

sensors

Article Safety and Traceability in Patient Healthcare through the Integration of RFID Technology for Intravenous Mixtures in the Prescription-Validation- Elaboration-Dispensation-Administration Circuit to Day Hospital Patients

María Martínez Pérez 1,*, Guillermo Vázquez González 2 and Carlos Dafonte 1

1 Department of Information and Communications Technologies, Faculty of Computer Science, Campus Elviña S/N, University of A Coruña, E-15071 A Coruña, Spain; [email protected] 2 A Coruña Universitary Hospital, Xubias de Arriba 84, E-15006 A Coruña, Spain; [email protected] * Correspondence: [email protected]; Tel.: +34-981-167-000

Academic Editors: Vladimir Villarreal and Carmelo R. García Received: 25 May 2016; Accepted: 23 July 2016; Published: 28 July 2016

Abstract: This work presents the integration of the RFID technology with the aim of ensuring the traceability of patients and minimization of adverse events during the process of prescription-validation-elaboration-dispensation-administration of medication by means of the implementation of various passive and active WIFI RFID systems in the Pharmacy and Day Hospital services of the Complejo Hospitalario Universitario A Coruña. Obtaining patient traceability and using the patient/drug binomial during this process allows us to minimize the occurrence of adverse events. The key points in this work are the unmistakably unique identiﬁcation and accurate real time location of the controlled items (patients and medication). RFID technology has proved to be invaluable in assisting with the everyday clinical practice of a hospital, and has been successfully implemented in this environment and others. In services such as the day hospital, the implementation of said technology is further justiﬁed by the high costs of the service and the high risk to the patient.

Keywords: RFID; traceability; safety; adverse effects

1. Introduction The concern of medical professionals regarding patient safety in the assistance process is nothing new: a robust public healthcare service has many positive effects on the population including wealth generation, social cohesion, increased productivity, consumption growth, and increased research. The public healthcare system is a source of social and economic wealth that creates jobs and plays an important role in preventing premature mortality by increasing and improving the quality of life of citizens. Patient safety [1,2] is one factor that indicates the quality status of health services and is considered a priority in healthcare. Maintaining patient safety is an increasingly complex task, as it involves potential risk and there is no method that can guarantee the absence of errors. It should be noted that, in healthcare tasks, there is a combination between factors inherent to the environment and human actions [3–6], and this is a possible cause of what are called adverse events (all situations that occur during the patient care process which do not originate in the underlying health condition but can cause signiﬁcant damage or even death), which are possibly caused by a combination of environmental factors and human actions [3–6].

Sensors 2016, 16, 1188; doi:10.3390/s16081188 www.mdpi.com/journal/sensors Sensors 2016, 16, 1188 2 of 23

Traceability of patients and medications may be even more important for those drugs that are considered high risk and cost since, in addition to the perfect dosage, it greatly facilitates the sustainability of the public health system. This paper mainly focuses on three types of intravenous mixtures: tocilizumab, abatacept, Remicade® (infliximab) and Inflectra™ (biosimilar infliximab), dosified in the Pharmacy Service and administrated at the Day Hospital of A Coruña University Hospital (CHUAC), prescribed for rheumatological, neurological, or digestive diseases. The development of treatments is made according to the pharmacotherapeutic profile of the patient. Currently, a significant portion of the drugs that are administered to patients in the Day Hospital are prepared and dosed by the Pharmacy Service. These processes are protocolized and, prior to implementation, a record of the medication that is prepared for each patient (indication, dose, pattern) is made. Additionally, for each medication prepared, the lot and expiry date of each of the components, production date, and expiry of the final product are registered. All these records are made manually on paper and it is difficult to ensure the global traceability of the medication, especially if it has been some time since its preparation. Nevertheless the time of the prescription receipt, the departure from the Pharmacy Service, or its reception at the Day Hospital are not registered. Moreover, the Day Hospital is characterized by a high rotation of patients whose prescribed medication has long term established patterns (21 days, monthly, etc.). It is important to note that all the medication that is to be included in this work has special characteristics in the process of prescription, preparation, and/or administration to the patient. Usually, when a patient arrives at the Day Hospital he or she has to meet several requirements before the prescribed medication is administrated, i.e.,

1. Having a scheduled administration for that day. 2. Having medical tests with favorable results. 3. Prior medication that has already been given (necessary for the patient to be ready to receive the prescribed treatment, e.g., paracetamol).

When the patient meets the requirements described above, the practitioner requests that the Pharmacy Service prepares the medication, but in daily clinical practice there are certain situations that hinder the patient care process. The main problems detected are:

‚ Medication is received at the Day Hospital but the patient is no longer in the hospital. ‚ Medication is lost during transport from the Pharmacy Service at Day Hospital. ‚ When the drug reaches the Day Hospital neither the patient nor the nurse are notiﬁed.

The communication of incidents was realized by means of telephonic real time calls between both services (Pharmacy and Day Hospital) to know the reasons of the problem and to try to solve it. Prior to this study, when the Pharmacy Service had sent the medication, the key parameters of the intravenous mixture elaboration and administration (as shown in Table1) could not be seen visually or electronically on a single tag, in a quick and safe way. Therefore, traceability of patient and medication control is needed. Another key point in the care process is when the nursing staff has to administer a medication to the patient. It would be ideal to have labelled information containing a practical guide to the conditions of use of said drugs (see Table1) and the most important data concerning the treatment of the patient and other relevant information. It is also essential to automatically and correctly validate that the right medication is going to be administered to the patient. It is important to note that in both cases the Day Hospital and the Pharmacy Service are working on the basis of current quality standards such as the FDA Good Manufacturing Practice [7], the Requirements of Good Manufacture and Quality Control of the magisterial prescriptions and ofﬁcial preparations, and are of course on the same level of standards as hospitals with a similar level of environment and complexity. In addition, the CHUAC Pharmacy Service has been certiﬁed by ISO 9001:2000 since 2005. Sensors 2016, 16, 1188 3 of 23

Table 1. Key parameters in intravenous mixture.

Key Parameters Patient’s data Composition Elaboration time Pharmacist in charge Expedition time Health professional who prepared the medication Stability Special conditions of use Previous medication Infusion Rate Lot and expiry of the components Lot and expiry of the ﬁnal product Medication prepared

The team of the project decided that the best strategy to diminish the possible resistance to the change on the part of the sanitary personnel, is to involve them during all the phases of the life cycle of the project (analysis, design, implementation and tests). From the beginning of the project, the supervisors of area of the units (Pharmacy, Informatics, Rheumatology, Day Hospital) were present at the meetings. In addition, some managers of this sanitary personnel are researchers of a project PI10/02442 that has ﬁnanced part of this work. In the case that the medical personnel have to do more activities, we always remind them that the security of the patient comes ﬁrst. Furthermore, the sanitary personnel learned each of the new steps progressively, which was helpful for their learning process. They could always consult a person concerning their doubts about the project’s working method.

2. Objectives and Benefits The objective of this project is to improve patient safety in the process of prescription-validation- preparation-dosification-dispensation-administration of drugs at the CHUAC Day Hospital. This aim will be achieved by implanting a series of RFID systems in the Pharmacy Service and Day Hospital. These systems identify without mistake the patients, medicines, and the patient-prescribed medicine binomial. In addition, these systems ensure the traceability of the patients. The Real Time Location System calculates the location of the patients in real time. This work also facilitates the traceability of the intravenous mixtures, since they are prepared in the Pharmacy Service until finally they are administered to the patients in the Day Hospital. The main benefits of this work are: (1) minimizing the occurrence of adverse events, as developed RFID systems facilitate the accurate identification of the patient and the correctly prescribed medication; and (2) ensuring that nursing staff will administer the correct medication in the proper administrative conditions. Various health professionals will be able to check the location of the patients and medication in real time, detecting potential bottlenecks and thereby significantly improving the efficiency of the hospital. It is important to note that the CHUAC consumption of medication selected for this work and considered high risk, represents an annual cost estimated at approximately four to five million Euros (2014 data obtained through Cost Management and Consumption of Drugs, applications available in the Pharmacy Service of the A Coruña University Hospital). This means 3190 doses for an average of 511 patients per year in Day Hospital; the necessary investment in technology integration to take action in this process seems therefore fully justified. The start-up of this work has not changed the essential functioning of prescription-validation- elaboration-administration process for patients in the Day Hospital. The plan is described in Figure1. Sensors 2016, 16, 1188 4 of 23 Sensors 2016, 16, 1188 4 of 23

Figure 1. Plan of administration of medication in the Day Hospital. Figure 1. Plan of administration of medication in the Day Hospital.  If the physician prescribes the medication to the patient for the first time, the authorization from ‚ Ifthe the Hospital physician committee prescribes is needed. the medication When au tothorized, the patient patient for the treatment first time, can the proceed. authorization from  thePeriodically, Hospital committeethe physician is needed. schedules When the authorized,future administrations patient treatment to the patient. can proceed. ‚ Periodically,Before the patient the physician arrives schedulesat the hospital, the future theadministrations pharmacist has to validated the patient. and elaborated the ‚ Beforepreparation the patient orders of arrives the medication at the hospital, prescribed the pharmacistto the patient. has validated and elaborated the  preparationIn each scheduled orders administration, of the medication the prescribed patient goes to theto the patient. doctor to check if he or she is in good ‚ Inhealth each for scheduled treatment; administration, if so, the doctor the notifies patient goesthe Pharmacy to the doctor Service to check to start if he the or preparation she is in good of healththe medication. for treatment; if so, the doctor notifies the Pharmacy Service to start the preparation of  thePharmacy medication. staff develop and identify accurately the intravenous mixture to be administered to ‚ Pharmacythe patient. staff develop and identify accurately the intravenous mixture to be administered to  theFinally, patient. the nursing staff administer the medication to the patient: identify the patient and ‚ Finally,medication the and nursing check staff if everything administer has the been medication carried out to thein compliance patient: identify with all the administration patient and medicationstandards (dose, and check route, if pattern, everything infusion has beenrate, carriedexpiration out date, in compliance etc.). with all administration  standardsTherefore, (dose,the development route, pattern, of infusionsystems rate,responsi expirationble for date, obtaining etc.). traceability of patients and ‚ Therefore,medication thethrough development the use of emerging systems responsible and breakthrough for obtaining technologies traceability [8–10] of such patients as RFID and medication(the selection through of RFID the is usejustified of emerging in detail and in fo breakthroughllowing sections) technologies and its integration [8–10] such into as RFID hospital (the selectionstaff daily of practice, RFID is is justified essential. in detail in following sections) and its integration into hospital staff daily practice, is essential. 3. RFID Technology (Radio Frequency Identification) and Other Identifying Technologies 3. RFIDWe select Technology the RFID (Radio technology Frequency [11–13] Identification) for several reasons: and Other Identifying Technologies  WeTo provide select the an RFID additional technology value [to11 –the13] WIFI for several network reasons: available in the hospital. To avoid the deployment of a new network of antennae (more expensive, implies interrupting ‚ To provide an additional value to the WIFI network available in the hospital. the functioning of the hospital). ‚ To avoid the deployment of a new network of antennae (more expensive, implies interrupting the functioningIn addition, ofRFID the fulfills hospital). the requirements for the identification and location of the patients and medicines. RFID technology in recent years has been used in very different areas and has provided significantIn addition, benefits. RFID It is fulfills therefore the requirementsinteresting to for study the identificationthe viability of and its locationintegration of the into patients healthcare and medicines.environments RFID in order technology to improve in recent patient years safety has beenand the used quality in very of differentservice received areas and during has provided the care significantprocess. The benefits. diverse It characteristics is therefore interesting of RFID te tochnology study the components viability of itsallow integration the establishment into healthcare of a environmentslarge number inof orderdifferent to improve systems. patient However, safety th ande essential the quality operation of service of receivedRFID is duringfundamentally the care process.identicalThe in all; diverse a tag characteristics is attached to of the RFID object technology or person components to be identified allow thewhich establishment then sends of a a radio large numberfrequency of signal different with systems. the identify However,ing information the essential needed. operation A reader of RFID receives is fundamentally and transmits identicalthis data into a all; software a tag is application attached to which the object then orprocesses person it, to as be seen identified in Figure which 2. then sends a radio frequency signal with the identifying information needed. A reader receives and transmits this data to a software application which then processes it, as seen in Figure2.

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Figure 2. Operation of RFID technology. Figure 2. Operation of RFID technology. Readers can be fixed (antennae, ARCHS, access points, etc.) or mobile (tablet, PDAs, phones, Readersetc.). can Tags be can ﬁxed be active (antennae, if they are ARCHS, equipped accesswith their points, own energy etc.) orsource, mobile or passive (tablet, if they PDAs, use the phones, etc.). same energy source as the reader, and semi-active if their own energy is not used for transmitting Tags can be active if they are equipped with their own energy source, or passive if they use the same but to power the internal circuitry of the microchip. There are other important differences between energy sourceactive asand the passive reader, tags, andsuch as semi-active cost, available if sizes, their and own variations energy in iscoverage not used (higher for in transmitting active and but to power thelower internal in passive) circuitry (See Table of the 2). microchip. There are other important differences between active and passive tags, such as cost, available sizes, and variations in coverage (higher in active and lower in Table 2. Comparison of RFID readers and tags. passive) (See Table2). Fixed Reader Mobile Reader Active Tags Passive Tags Antennae Tablet Battery No Battery Table 2. Comparison of RFID readers and tags. Arches PDA Higher cost Lower cost and coverage Access points Mobile phone Larger size Longer lifetime Fixed Reader Mobile Reader Active Tags Passive Tags RFID componentAntennae coverage is Tablet the maximum di Batterystance in which a No communication Battery can be established (toArches read or write data in PDA its memory, change Higher its cost settings,Lower etc.). costApart and from coverage the operating frequency Accessof the system, points quality Mobile of coverage phone depend Largers on factors size such as Longer the power lifetime provided by the reader antenna and available on the tag itself, the surrounding conditions, the orientation of the tag at the time of reading, etc. Therefore, the values previously assumed for each tag are merely RFIDindicative. component There coverage are four possible is themaximum operating frequency distance of inan whichRFID system, a communication as shown in Table can 3: be established (to read or write data in its memory, change its settings, etc.). Apart from the operating frequency of the system, quality of coverage dependsTable 3. RFID on technology factors suchfrequency as theof operation. power provided by the reader antenna and available on the tag itself,Frequency the of surrounding Operation conditions, the Band orientation of the tag at the time of Low Frequency Below 135 kHz reading, etc. Therefore, the valuesHigh frequency previously assumed for 13.56 each MHz tag are merely indicative. There are four possible operating frequencyUltra High of frequency an RFID system, 433 MHz, as shown 860 MHz in and Table 928 MHz3. Microwaves 2.45 GHz and 5.8 GHz Table 3. RFID technology frequency of operation. The superiority and success of RFID technology over other identifying technologies lies mainly in the ability of its tags to store high quantities of information on subjects and/or other items. In Frequency of Operation Band addition, this data can be saved according to standards set by EPCglobal [14]. The tags are not damaged by use thanksLow to the Frequency variety of resistant materials used Below in their 135 kHzconstruction such as epoxy, which can withstand extremeHigh frequencytemperatures (as low as −21 °C) and 13.56 hundreds MHz can be read, written and updated simultaneously,Ultra without High frequency the need for direct433 contact MHz, with 860 the MHz reader. and 928These MHz properties make RFID the ideal technologyMicrowaves for traceability systems in a healthcare 2.45 GHz environment and 5.8 GHz (for cool/frozen or room temperature products, to identify patients, to use single doses of medication or infusion pumps, The superioritydefibrillators,and etc.). successTags are the of RFIDmost important technology components over other in RFID: identifying their design technologies is fully determined lies mainly in by the objects or subjects being tracked. There is a great variability of tags (shape and dimensions) the ability of its tags to store high quantities of information on subjects and/or other items. In addition, this data can be saved according to standards set by EPCglobal [14]. The tags are not damaged by use thanks to the variety of resistant materials used in their construction such as epoxy, which can withstand extreme temperatures (as low as ´21 ˝C) and hundreds can be read, written and updated simultaneously, without the need for direct contact with the reader. These properties make RFID the ideal technology for traceability systems in a healthcare environment (for cool/frozen or room temperature products, to identify patients, to use single doses of medication or infusion pumps, deﬁbrillators, etc.). Tags are the most important components in RFID: their design is fully determined by the objects or subjects being tracked. There is a great variability of tags (shape and dimensions) and if the correct isolation is selected they can be read regardless of the material on which they are attached. Sensors 2016, 16, 1188 6 of 23

At present, several identifying technologies on the market could solve partially or completely the requirements outlined in this paper. Given the characteristics of this project, the selected technology must have the following functions:

‚ Unmistakably identify patients and medication. ‚ Estimate the location of a patient and/or an asset with good accuracy (1 to 4 m). ‚ Consist in physically comfortable devices during the patient’s stay at the hospital. ‚ Be suitable for a sterilization process.

This error range is acceptable and suitable considering the size of each of the areas to be controlled. It is essential to know if a patient is waiting or if he/she is being seen by a physician. Often different rooms are adjoining rooms and therefore location accuracy is key in determining that the system functions correctly and that the information provided is accurate. The Day Hospital is located on the ground floor of the CHUAC. We need this precision because on the same floor and adjacent to it are the patient waiting rooms, the medical area, and rooms dedicated to the administration of the medication to the patient. Having fulfilled the above requirements, the need to minimize disruptive construction work in the hospital and the reuse of existing infrastructure in the same (providing a new network value through already installed antennae) and therefore minimizing costs, are decisive in the selection of the technology that will address the development of this work. The following options were evaluated: ultrasound (Sonitor), infrared, ZigBee, and RFID. Table4 shows the values of essential parameters for the proper functioning of the system to be developed in this work.

Table 4. Comparison of different identifying technologies.

Ultrasounds Infrared (NPS RFID (UHF, HF, NFC, Zigbee Feature (Sonitor) ActiveTrack) Ekahau, Aeroscout) (Awarepoint) Unmistakably identiﬁcation of Yes Yes Yes Yes the patient Unmistakably identiﬁcation of No No Yes No the medication Accurate location between No No Yes No 1 and 4 m Location at area level Yes Yes Yes Yes No Autoclave sterilization process (Disposable No No Yes case tags) Readings interference, attached to certain materials (metals, No No Yes No liquids in plastics and glass) Comfortable device for Yes Yes Yes Yes the patient Possible reuse of hospital No No Yes No WIFI infrastructure

The conclusions that appear in the table are the result of our real experimentation with the indicated technologies [14]. We have tested different labels, frequencies, size of labels, distances of reading and/or writing for each of the technologies. This experimentation is key for the success in the design of the technical architecture of the system. After analyzing the above table, it can be said that RFID is the most suitable technology for the identiﬁcation of drugs. This is due to the wide variety of shapes, sizes, and material of the tags, which can be adapted to almost any item/subject. Other technologies do not have adequately sized/shaped tags to identify unit doses of medication. One of the main disadvantages of RFID is the interference that can arise in the readings if the labels are attached to certain materials. In this work that obstacle has been overcome by attaching the tags in a “Flag Mode”, as detailed in the design section. Sensors 2016, 16, 1188 7 of 23

Regarding real time location, the accuracy of calculating the position of the patients has been essential due to the proximity of the different controlled areas and the use of a WIFI network in the hospital. The major disadvantage has been the high cost, along with the lack of automation in some of the necessary processes, which can be overcome with proper design. Recently RFID technology has been experimented with in healthcare environments. Many functions have been developed, such as the implementation of algorithms to improve communication between tags and RFIDSensors readers, 2016, 16, 1188 RFID identification of patients to dispense electronically prescribed7 of 23 medication, mobile applicationshospital. The that major facilitate disadvantage monitoring has been the of high patients cost, along at with their the home lack of addresses,automation in locationsome of assets and patientsof using the necessary active processes, tags, passive which can tags, be overcome WIFI active with proper tags, design. RFID automatic medication dispensers, etc. All these functionsRecently RFID are intended technology tohas increase been experime the patientnted with care in healthcare process safely,environments. facilitating Many traceability functions have been developed, such as the implementation of algorithms to improve communication of patients andbetween prescribed/elaborated/dispensed/administered tags and RFID readers, RFID identification of patients to dispense medication. electronically prescribed medication, mobile applications that facilitate monitoring of patients at their home addresses, 4. Developmentlocation of assets and patients using active tags, passive tags, WIFI active tags, RFID automatic medication dispensers, etc. All these functions are intended to increase the patient care process safely, 4.1. Analysisfacilitating traceability of patients and prescribed/elaborated/dispensed/administered medication. The first4. phaseDevelopment of project development is the analysis of the process of prescription-validation- elaboration-dispensing-administration4.1. Analysis of drugs in the Pharmacy Service and Day Hospital of the A Coruña UniversityThe first Hospital. phase of Theproject main development objective is the was analysis to studyof the process the performance of prescription-validation- of these services and discover theelaboration-dispensing-administration pathway medicines and patients of drugs follow in the Pharmacy from arriving Service and at Day the Hospital hospital of the until A they leave. This will enableCoruña detection University of thoseHospital. critical The main points objective where was theto study implementation the performance of of RFID these services technology and is necessary discover the pathway medicines and patients follow from arriving at the hospital until they leave. to minimizeThis the will occurrence enable detection of adverse of those events critical poin andts thereforewhere the implementation increase safety of RFID in thetechnology patient is care process. The methodologynecessary to minimize used in the this occurrence phase of (as adverse seen even ints Figure and therefore3) is based increase on safety successive in the patient meetings with healthcare professionalscare process. as experts in each field. The aim of this phase is to acquire existing knowledge. The methodology used in this phase (as seen in Figure 3) is based on successive meetings with This processhealthcare is iterative professionals and progressive, as experts andin each with field. each The iterationaim of this diagrams phase is to are acquire obtained existing and presented for expert review.knowledge. This This way, process medical is iterative staff and can progressive, confirm and that with knowledge each iteration acquired diagrams are is correctobtained or can make suggestionsand for presented possible for improvements. expert review. This The way, softwaremedical staff engineer can confirm builds that knowledge more refined acquired models is in each correct or can make suggestions for possible improvements. The software engineer builds more iteration andrefined facilitates models the in each transmission iteration and facilitates of the specialist the transmission knowledge. of the specialist knowledge.

Figure 3. Analysis phase methodology. Figure 3. Analysis phase methodology. In order to present graphically all knowledge after the application of the methodology described, a tool called Architecture of Integrated Information System (AIRIS) was used. Its main target is to In orderfacilitate to present the development, graphically implementation, all knowledge and cont afterrol theof the application business processes. of the Although methodology it has described, a tool calleddifferent Architecture types of diagrams of Integrated available, Informationin this case the work System protocol (AIRIS) Chain of was Processes used. guided Its by main target is to facilitate theEvents development, (CPE) is represented implementation, and allows to articu andlate control any process of thein terms business of events, processes. functions, Although it documents, jobs, control flows, and rules connection. has different typesEvents of trigger diagrams functions available, and are a result in this of these. case Functions the work indicate protocol the activities Chain carried of Processesout in guided by Events (CPE)the process is represented at any time and and the allows time spent to articulateon the same. any Documents process are in objects terms representing of events, functions, documents,jobs, control ﬂows, and rules connection. Events trigger functions and are a result of these. Functions indicate the activities carried out in the process at any time and the time spent on the same. Documents are objects representing documents that are used in the process, while position indicates which professional category is performing a function. Sensors 2016, 16, 1188 8 of 23

4.2. Design This section is about describing and justifying the design of the RFID technical architecture necessary to achieve the objectives of this work, which were integrated in the Pharmacy Service and Day Hospital.

4.2.1. RFID System for Traceability of Patients and RFID Transportation Cart There are multiple solutions for tracking people and the transportation cart of intravenous mixtures prepared by RFID. This technology has several frequencies and each of them requires different components and can calculate the position with a certain precision. Table5 shows a comparison of the major frequencies used for obtaining RFID traceability. The key parameters for the selection of RFID components in this work are: ‚ Calculating position with an accuracy of 1 to 4 m. ‚ Minimizing costs. ‚ Minimizing remodeling/construction works and thereby avoiding disruption of the normal operation of the hospital, and of course by making full use of the already available WIFI network in the hospital.

Table 5. Different methods for obtaining traceability with RFID.

Feature Active Tags WIFI Active Tags UHF Passive Tags Accurate location between 1 and 4 m No Yes No Location at area level Yes Yes Yes Possible reuse of hospital WIFI infrastructure No Yes No

Analyzing the values of the parameters that can be seen in Table2, active WIFI tags have been selected to locate patients and the medication cart, meeting the requirements deﬁned. Currently there are two major competitors on the market for locating systems using active WIFI Real Time Location System (RTLS): Aeroscout and Ehakau. Aeroscout (Lincoln, NE, Nebraska) has been selected for this work for the following reasons: ‚ Higher localization accuracy. ‚ Active WIFI tags from both manufacturers have similar sizes, but Aeroscout is considered more comfortable for the patient in shape. ‚ Both systems support Cisco (the manufacturer of the WIFI network available in the hospital therefore minimizing the required infrastructure costs), but Ekahau requires an IP address for each tag and this could cause problems with the network management. Table6 shows a summary of the users, hardware components, and software of the RFID technical architecture.

Table 6. Technical architecture of the RFID system in tracking patients and the medication cart.

Users Hardware Owned Software Cisco access points, Aironet Medical staff Mobile View 1130 AG model Pharmaceutical Staff Hospital Location engine Cisco MSE Exciters EX-2000B Pharmacy Specialist Locator 3350 Nursing staff from the AeroscoutExciter Detector Tag Management Suite Day Hospital BWH-3000-SV Aeroscout Network Exciter TagActivator Manager NEM-1000 WIFI active tag Aeroscout T2 Sensors 2016, 16, 1188 9 of 23 Sensors 2016, 16, 1188 9 of 23

TheseSensorsThese 2016 are are, 16 the ,the 1188 hardware hardware components components ofof thethe RFIDRFID system as as seen seen in in Figures Figures 44 and and 5:5: 9 of 23

‚  CiscoCiscoThese Access Access are Point,the Point, hardware Aironet Aironet components 11301130 AGAG of model:model: the RFID as as systema a reference reference as seen for for in calculating calculatingFigures 4 and the the 5: position position of ofthe the patient,patient, at at least least three three access access points points must must simultaneouslysimultaneously detect the the patient patient to to calculate calculate his/her his/her  Cisco Access Point, Aironet 1130 AG model: as a reference for calculating the position of the position.position. This This manufacturer manufacturer has has been been selected selected because because thesame the same WIFI networkWIFI network is already is already available availablepatient, in at the least hospital. three access points must simultaneously detect the patient to calculate his/her in theposition. hospital. This manufacturer has been selected because the same WIFI network is already  EX2000B Exciter: to improve the calculation of the location accuracy. The main function of these ‚ EX2000Bavailable Exciter: in the to hospital. improve the calculation of the location accuracy. The main function of these devices is to communicate to the location engine which active WIFI tags are detected within their devices EX2000B is to communicate Exciter: to improve to the the location calculation engine of th whiche location active accuracy. WIFI The tags main are detected function of within these their range. The engineer in the design phase is responsible for entering the physical location of range.devices The engineer is to communicate in the design to the phase location is responsibleengine which for active entering WIFI tags the physicalare detected location within of their exciters exciters into the engine map location manually, so when an exciter indicates that it has detected into therange. engine The engineer map location in the manually, design phase so whenis resp anonsible exciter for indicates entering the that physical it has detected location aof label, a label, accuracy in the location calculation is high. Information obtained through the exciters accuracyexciters in theinto location the engine calculation map location is high. manually, Information so when obtainedan exciter throughindicates thethat exciters it has detected can correct cana correctlabel, accuracy discrepancies in the locationin locations calculation registered is high. through Information the WIFI obtained access points. through the exciters discrepancies in locations registered through the WIFI access points.  Aeroscoutcan correct Exciter discrepancies Detector in BWH-3000-SV: locations registered A devi throughce for the applying WIFI access Aeroscout points. Network Exciter ‚ Aeroscout ManagerAeroscout Exciterwhich Exciter monitors Detector Detector data BWH-3000-SV: BWH-3000-SV: concerning the AA devicedevi coveragece for for applyingrange applying and Aeroscout Aeroscoutsignal strength Network Network of Exciter exciters Exciter ManagerdetectedManager which at allwhich times. monitors monitors data data concerning concerning thethe coverage range range and and signal signal strength strength of exciters of exciters  detectedTagdetected Activator: at all at times. all times.A device that facilitates communication between Tag Management Suite ‚ Tag application Activator:Tag Activator: and A device AeroScout A device that facilitatesWIFI that activefacilitates communication tags (simultaneouslycommunication between betweendetects Tag Management one Tag or Managementmore tags Suite that application Suite are in andthe AeroScoutapplication coverage WIFI range). and activeAeroScout tags (simultaneouslyWIFI active tags (simultaneously detects one or more detects tags one that or are more in thetags coverage that are in range). ‚  WIFIWIFIthe active activecoverage tag tag Aeroscout range). Aeroscout T2: T2: to to knowknow thethe locationlocation of the the patient patient and and the the cart. cart.   RFIDWIFI cart: active to transport tag Aeroscout and obtainT2: to know the traceability the location of of intravenous the patient and mixtures. the cart. ‚ RFID cart: to transport and obtain the traceability of intravenous mixtures.  RFID cart: to transport and obtain the traceability of intravenous mixtures.

Figure 4. RFID System for Traceability of RFID Transportation Cart. FigureFigure 4. 4. RFID RFID System System for for Traceability Traceability of RFID TransportationTransportation Cart. Cart.

Figure 5. RFID System for Traceability of Patients. Figure 5. Figure 5. RFIDRFID System for Traceability Traceability of of Patients. Patients.

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The RFID software components consist of the following:

‚ Mobile View: This application is proprietary to the Aeroscout manufacturer. It is the location engine interface and displays the traceability of any controlled asset. That is, the user can consult a graphic representing an individual patient for a period of time and his/her course during the stay in the hospital. It analyzes waiting time, processing, administration of drugs etc. and therefore facilitates the detection of bottlenecks and improves the operation of the service. It manages prohibited areas access alerts and abandonment by the patient of the hospital before drug administration (an action that should paralyze the elaboration of intravenous mixture in the Pharmacy). In addition, the user defines the buildings, floors and areas where the patients would be controlled [15]. ‚ Cisco Mobility Service Engine MSE Locator 3350: calculates the position of patients using different algorithms and considering the access points that detect the tagged patient at all times; in this case the algorithm used is the RSSI which is intended for indoor location. This location engine has been selected because it is the one that requires the Aeroscout manufacturer for WiFi networks integrated by Cisco access points. ‚ Tag Management Suite: application property of Aeroscout manufacturer that enables, disables, and configures WIFI active tags parameters (frequency and broadcast channels, etc.). ‚ Aeroscout Network Exciter Manager NEM-1000: application property of Aeroscout manufacturer to manage and configure exciters in a Cisco LWAPP environment.

4.2.2. RFID System for Medication Preparation in the Pharmacy Service This system is responsible for the unmistakable identiﬁcation of intravenous mixtures created in the Pharmacy Service and subsequently administered to patients in the Day Hospital. Table7 shows the users, and the hardware and software components of the system.

Table 7. Technical architecture of the RFID system in the preparation of medication in the Pharmacy Service.

Users Hardware Software Developed in the IT Service Nursing staff from the Pharmacy Toshiba B-EV4D-GS14-QM-R Printer RFID protocol for Day Hospital Service Dual Passive Tag Reader RD 200-U1-G (UHF) Reader RD 200-M1-G (NFC)

These are the hardware components of the RFID system as seen in Figure6:

‚ Toshiba B-EV4D-GS14-QM-R Printer: Prints the tags that will identify the prepared intravenous mixtures. ‚ Dual passive tag with NFC (NXP NTAG203, ISO 14 443 A) + UHF (Monza 4, Operating Frequency 860–960 MHz, International Standards EPC Class 1 Gen 2, ISO 18000-6C): Passive tags made and designed at size 100 mm ˆ 70 mm. The tag is attached to the intravenous mixture in the “Flag Mode” to prevent possible RFID interference with liquids, and contains in a single label two passive RFID tags in two different UHF and NFC frequencies. The UHF tag (this frequency has been chosen so it can be read within the RFID cart) will be detected in the RFID system for medication traceability instead; the NFC tag (this frequency was selected since the readings will be made between short distances) is designed to operate in the RFID system for medication administration to the patient. Both systems are described in detail below. ‚ RD 200-U1-G (UHF) y RD 200-M1-G (NFC) Reader: Once the medication is prepared and labeled, it is necessary to associate the tag that identifies the prepared mixture. To do this, two specific USB readers for each frequency automatically read the unique identification item (UID) of the NFC and UHF tags, by simply moving them closer to the readers. Both devices have the same design. Sensors 2016, 16, 1188 11 of 23

Sensors 2016, 16, 1188 11 of 23 It is important to note that these devices are difﬁcult to acquire as they are the only models that do notEPC need tag data additional in keyboard software emulator development mode. This and has greatly they are expedited able to writethe implementation UIDs and EPC of this tag data in keyboardwork. emulator mode. This has greatly expedited the implementation of this work.

FigureFigure 6. RFID 6. RFID System System for for Medication Medication Prep Preparationaration in in the the Pharmacy Pharmacy Service. Service.

There is an application that electronically records the process of prescription-validation- Theredispensation-administration is an application thatof medication electronically in the Pharmacy records theService process and Day of Hospital prescription-validation- that follows dispensation-administrationthe Day Hospital RFID protocol. of medication in the Pharmacy Service and Day Hospital that follows the Day Hospital RFID protocol. 4.2.3. RFID System for Intravenous Mixtures Traceability 4.2.3. RFIDThis System system for manages Intravenous traceability Mixtures of intravenous Traceability mixtures during transport, from elaboration at Thisthe Pharmacy system managesService until traceability final delivery of intravenous in the Day Hospital. mixtures When during the nursing transport, staff fromfinish elaborationlabelling, at they enter the medication on the intravenous mixtures RFID cart for its administration to the patient the Pharmacy Service until final delivery in the Day Hospital. When the nursing staff finish labelling, in the Day Hospital. This cart is an innovating and differentiating factor, because with the antennae they enter the medication on the intravenous mixtures RFID cart for its administration to the patient in it contains inside it is able to provide a list of the medication it contains in real time and with a the Dayfrequency Hospital. of retransmission This cart is anpreviously innovating defined and by differentiating the user. Its operating factor, mode because is based with on the the antennae mass it containsreading inside of UHF it is abletags tofrom provide medicines a list contained of the medication within. Atit the contains same time in real it provides time and information with a frequency on of retransmissionthe mixture (drug, previously dose, route, defined pattern, by etc.) the user.and pa Itstient operating (medicalmode history is number, based on name, the service, mass reading etc.) of UHFto tags which from each medicines belongs. contained within. At the same time it provides information on the mixture (drug, dose,The route,first time pattern, the cart etc.) detects and the patient UHF tag (medical that iden historytifies a mixture, number, it name,automatically service, sets etc.) the date to which eachand belongs. time sent. Also this cart is characterized by having a WIFI active tag (the same as the patient) that Thefacilitates first timethe control the cart of detectstraceability the UHFin real tag time; that therefore identifies its aposition mixture, or route it automatically for a periodsets of time the date can be checked at any time set in the Mobile View application, i.e., the RFID system allows the route and time sent. Also this cart is characterized by having a WIFI active tag (the same as the patient) that used by the medication during transport from the Pharmacy Service to the Day Hospital to be facilitates the control of traceability in real time; therefore its position or route for a period of time can monitored. be checkedThe at complex any time construction set in the Mobile of this Viewcart is application, noteworthy, i.e.,since the it RFIDoffers systemalmost 100% allows reliability the route in used by thereadings medication and is during able to transportread content from only, the without Pharmacy detection Service errors to thewith Day external Hospital tags, toregardless be monitored. of Thehow complexclose they constructionare. Without RFID of this technology cart is noteworthy,this would be quite since difficult it offers to almostachieve. 100% reliability in readingsWhen and is the able cart to has read reached content the only,Day Hospital without it detectionis essential errors to record with the external delivery tags,of drugs regardless to the of how closenursing they staff. are. To Withoutdo this, the RFID orderly technology must deposit this wouldmixtures be above quite an difficult RFID tray, to achieve. also an innovating Whenelement, the which cart displays has reached data theof the Day mixture Hospital and itthe is patient essential for towhom record it has the been delivery prepared. of drugs At the to the nursingsame staff. time To the do RFID this, system the orderly reads mustthe UHF deposit chip fr mixturesom that drug, above including an RFID the tray, time also and an date innovating of delivery. It is important to note that together with the information provided by the RFID system element, which displays data of the mixture and the patient for whom it has been prepared. At the described above, it can also provide real time location of any intravenous mixture since the content same time the RFID system reads the UHF chip from that drug, including the time and date of delivery. and location of the cart is known at all times. Table 8 shows the users, hardware components, and It is importantsystem software: to note that together with the information provided by the RFID system described above, it can also provide real time location of any intravenous mixture since the content and location of the cart is known at all times. Table8 shows the users, hardware components, and system software.

Sensors 2016, 16, 1188 12 of 23

Table 8. Technical architecture of the RFID system for intravenous mixtures traceability.

Software Components Users Hardware Components Sensors 2016, 16, 1188 Developed in the IT12 Serviceof 23 Medical staff Dual passive tag RFID protocol for Day Hospital Table 8. Technical architecture of the RFID system for intravenous mixtures traceability. Pharmaceutical Staff Hospital RFID transportation cartSoftware Cart Components RFID Real Time Pharmacy SpecialistUsers Hardware Components Developed in the IT Service Nursing staff fromMedical the Day staff Hospital Aeroscout Dual passive T2 WIFI tag active tag RFID protocolTray for RFID Day Hospital Real Time Pharmaceutical Staff Hospital RFID transportationRFID tag cart Cart RFID Real Time Pharmacy Specialist Nursing staff from the Day Hospital Aeroscout T2 WIFI active tag Tray RFID Real Time The hardware components of RFID systemRFID as shown tag in Figure7 are the following:

‚ PassiveThe dual hardware tag with components NFC+UHF: of RFID tag system for identifying as shown in intravenous Figure 7 are the mixtures. following: ‚ RFID cart:Passive For dual transporting tag with NFC+UHF: intravenous tag for mixtures identifying and intravenous obtaining mixtures. traceability.

‚ Active RFID WIFI cart: tag For Aeroscout transporting T2: intravenou for the locations mixtures of theand cart.obtaining traceability.  Active WIFI tag Aeroscout T2: for the location of the cart. ‚ RFID tray:RFID for tray: controlling for controlling the the delivery delivery of of medication medication in in the the Day Day Hospital. Hospital.

FigureFigure 7. RFID 7. RFID System Systemfor for Intravenous Mixtures Mixtures Traceability. Traceability.

The software components of the RFID system are: The software components of the RFID system are:  RFID Protocol for Day Hospital: application that electronically records the process of prescription-validation-dispensation-administration of medication in the Pharmacy Service and ‚ RFID Protocol for Day Hospital: application that electronically records the process of the Day Hospital. prescription-validation-dispensation-administration Cart RFID Real Time: application developed in the IT of Service medication to display in real the Pharmacytime information Service and the Dayon Hospital. intravenous mixtures that are placed inside the cart (patient name, medication, dosage, etc.). ‚ Cart RFIDThe first Real time Time: the applicationcart reads a developedtag it sets th ine time the ITof Serviceshipment toof displaythe intravenous real time mixture information on intravenousidentified. mixtures that are placed inside the cart (patient name, medication, dosage, etc.).  Tray RFID Real Time: an application developed in the IT Service to display real time information The first time the cart reads a tag it sets the time of shipment of the intravenous mixture identified. on intravenous mixtures that are above the tray (patient name, medication, dosage, etc.). The ‚ Tray RFIDfirst time Real the Time: tray anreads application a tag, it sets developed the time for indelivery the IT of Service the identified to display intravenous real time mixture. information on intravenous mixtures that are above the tray (patient name, medication, dosage, etc.). The first time4.2.4. the RFID tray System reads for a tag, Medication it sets the Administration time for delivery to the Patient of the identified intravenous mixture. This system is responsible for the traceability and safety of medication administration to the 4.2.4. RFIDpatients System in the forDay Medication Hospital. When Administration the nursing staff to administer the Patient the intravenous mixture to a patient, it is essential that they can check that the prescribed medication is administered in suitable conditions. This system is responsible for the traceability and safety of medication administration to the To do this, the nursing staff (using a mobile device, an Android phone that has an integrated NFC patients in the Day Hospital. When the nursing staff administer the intravenous mixture to a patient, it is essential that they can check that the prescribed medication is administered in suitable conditions. Sensors 2016, 16, 1188 13 of 23

To do this, the nursing staff (using a mobile device, an Android phone that has an integrated NFC reader) read the NFC chip from the intravenous mixture and subsequently they read the NHC from the patient. From that moment onwards the application issues alerts relating to the administration of the drug to the patient, such as: route, pattern, conditions of administration, intravenous mixture expiry date,Sensors and2016, 16 whether, 1188 the drug has been prescribed or had been given to the patient previously,13 of 23 etc.

It isreader) important read the to NFC note chip that from this the processintravenous signiﬁcantly mixture and increasessubsequently patient they read safety the NHC by minimizing from the the occurrencepatient. of adverseFrom that events moment and onwards thus improvesthe application the qualityissues alerts of therelating patient to the care administration process during of the the stay in the hospital.drug to the Table patient,9 shows such as: the route, users pattern, and the conditions hardware of administration, and software intravenous components mixture of this expiry system. date, and whether the drug has been prescribed or had been given to the patient previously, etc. Table 9.It Technicalis important architecture to note that of this the process RFID system significantly in the administrationincreases patient of safety medication by minimizing to the patient. the occurrence of adverse events and thus improves the quality of the patient care process during the stay in the hospital. Table 9 shows the users and the hardware and Softwaresoftware Componentscomponents of this Users Hardware Components system: Developed in the IT Service Nursing staff from the Dual passive tag with NFC + UHF AndRFID TableDay 9. Hospital Technical architecture of the RFID system in the administration of medication to the patient. Users HardwareAeroscout Components T2 WIFI active Software tag Comp RFIDonents protocol Developed for Dayin the Hospital IT Service Nursing staff from the Dual passive tag with NFC + UHF AndRFID Day Hospital Mobile phone with integrated NFC Aeroscout T2 WIFI active tag RFID protocol for Day Hospital Mobile phone with integrated NFC The hardware components of the RFID system, as shown in Figure8, are: ‚ Dual passiveThe hardware tag with components NFC + UHF:of the RFID A tag system, to identify as shown intravenous in Figure 8, mixtures. are: ‚ Android Dual mobile passive with tag with NFC: NFC in + orerUHF: to A checktag to identify that the intravenous correct medication mixtures. is administered to the patient. Android This device mobile haswith beenNFC: selectedin orer to forcheck its that low the cost correct within medication the range is administered of mobile phonesto the with integratedpatient. NFC This readers. device has In addition,been selected the for screen its lo sizew cost and within interface the range usability of mobile minimize phones with the training integrated NFC readers. In addition, the screen size and interface usability minimize the training periodperiod with healthwith health professionals. professionals. ‚ Active Active WIFI tagWIFI Aeroscout tag Aeroscout T2: T2: used used to to identify identify the patient. patient.

FigureFigure 8. RFID 8. RFID System System for for Medication Medication Ad Administrationministration to the to Patient. the Patient. The software components for this RFID system are the following: The software components for this RFID system are the following:  RFID Protocol for Day Hospital: an application that electronically records the process of ‚ RFID Protocolprescription-validation-dispensation-administratio for Day Hospital: an applicationn of that medication electronically in the Pharmacy records Service the and process of prescription-validation-dispensation-administrationDay Hospital. of medication in the Pharmacy Service and

Day Hospital.AndRFID: an application developed by the CHUAC IT Service for the nursing staff to check accurately and without error that the prescribed medication is administered to the patients, and ‚ AndRFID:in suitable an application conditions (route, developed dose, pattern, by the infusion CHUAC rate, IT stability, Service expiration for the date, nursing etc.). staff to check accurately and without error that the prescribed medication is administered to the patients, and

in suitable conditions (route, dose, pattern, infusion rate, stability, expiration date, etc.).

Sensors 2016, 16, 1188 14 of 23

4.3. ImplementationSensors 2016, 16, 1188 14 of 23

This4.3. Implementation section will describe how the implementation of RFID hardware and software (detailed in the above design section) was carried out. This phase is divided into different stages and each is This section will describe how the implementation of RFID hardware and software (detailed in characterized by the grouping together of tasks of different natures. Moreover, the stages are designed the above design section) was carried out. This phase is divided into different stages and each is so their development is performed simultaneously and that the global time-scale of implementation characterized by the grouping together of tasks of different natures. Moreover, the stages are can bedesigned expedited. so their development is performed simultaneously and that the global time-scale of Softwareimplementation development can be expedited. has followed the standards defined by the Galician Health Service (Servizo Galego deSoftware Saúde, SERGAS)development based has onfollowed Metric the V3.4, standard in orders defined to ensure by thatthe theGalician results Health have Service the highest level(Servizo of quality Galego possible de Saúde, and SERGAS) at the same based time on Metric meet V3.4, the in standards order to ensure set by that SERGAS the results for have corporative the systemshighest that level will beof putquality into possible daily clinical and at practice the same production. time meet the standards set by SERGAS for Itcorporative is important systems to emphasize that will be that put there into daily is a software clinical practice interface production. for the system in which all the events of traceabilityIt is important (generated to emphasize by the different that there devices is a so RFIDftware and interface available for the as backend)system in canwhich be all registered, the events of traceability (generated by the different devices RFID and available as backend) can be consulted, and analyzed by the users. The following section describes in detail each of these stages. registered, consulted, and analyzed by the users. The following section describes in detail each of 4.3.1.these Aeroscout stages: RTLS The4.3.1. mainAeroscout objective RTLS of this stage is to install and configure the Aeroscout manufacturer infrastructureThe main for the objective traceability of this of patients,stage is to medications, install and orconfigure other items the Aeroscout to be controlled manufacturer by an RTLS system.infrastructure More specifically, for the traceability the RFID of system patients, for medications, traceability or of other patients items and to be the controlled RFID transportation by an RTLS cart is describedsystem. More in the specifically, design phase. the RFID The system first step for consiststraceability in enteringof patients floor and plansthe RFID to controltransportation the engine location.cart is In described this case in the the floors design are phase. the following: The first step consists in entering floor plans to control the engine location. In this case the floors are the following: ‚ Floor 1: Pharmacy Service.  Floor 1: Pharmacy Service. ‚ Level 0: Day Hospital, Cafeteria, hospital gateway and exit.  Level 0: Day Hospital, Cafeteria, hospital gateway and exit. LaterLater in the in the Mobile Mobile View, View, the the following following parameters parameters must must be be set set as as seen seen in inFigure Figure 9: 9.

Figure 9. Mobile View tasks. Figure 9. Mobile View tasks.

 Define the structure of the buildings, floors, and controlled areas ‚ Define the structure of the buildings, floors, and controlled areas  Enter the plans of each of the floors. Set additional possible alerts for: access zones, and access ‚ Enteror the exit plans alertsof for each certain of thegroup floors. of tags. Set additional possible alerts for: access zones, and access or exit alertsDecide for what certain actions group to take of tags.if alerts occur. These messages are sent as mobile texts messages ‚ Decideand/or what emails actions depending to take on if user alerts needs. occur. In the These following messages cases, arealerts sent are asalways mobile transmitted texts messages by and/oremails emails to different depending health on profes usersionals: needs. patient In the arriving/leaving following cases, the alerts hospital, are alwaysRFID cart transmitted reaching by emailsthe to Day different Hospital health or leaving professionals: the Pharmacy patient Service, arriving/leaving etc. the hospital, RFID cart reaching the DayOnce Hospital the physical or leaving space is the defined, Pharmacy we must Service, carry etc.out a coverage study in order to obtain the following data: Once the physical space is defined, we must carry out a coverage study in order to obtain the following data: Sensors 2016, 16, 1188 15 of 23

Sensors 2016, 16, 1188 15 of 23 - The localization accuracy that can be obtained with the available WIFI infrastructure. -- HowThe localization the WIFI network accuracy should that can be modiﬁedbe obtained regarding with the theavailable number WIFI of accessinfrastructure. points and their - positionHow the in WIFI order network to enable should an RTLS be accuracy modified of regarding between 1 the and number 4 m. of access points and their Theposition localization in order accuracy to enable that an can RTLS be obtainedaccuracy of with between the WIFI 1 and infrastructure 4 m. available. How the WIFI networkThe localization should be accuracy modiﬁed that regarding can be obtained the number with of the access WIFI points infrastructure and their positionavailable. to How enable the anWIFI RTLS network accuracy should of between be modified 1 and 4regarding m. the number of access points and their position to enable an RTLSThe parameters accuracy of that between have determined 1 and 4 m. this report are the following: The parameters that have determined this report are the following: ‚ Physical location of each of the access points. ‚  PhysicalPhysical location location of of the each antennae. of the access points. ‚  TypesPhysical of antennae. location of the antennae. ‚  FrequenciesTypes of antennae. and channels used for each access point. Frequencies and channels used for each access point. ‚  Transmission power of each point.  Transmission power of each point. ‚ Signal range for each access point (signal strength in the environment) SNR (Signal-to-Noise Ratio).  Signal range for each access point (signal strength in the environment) SNR (Signal-to-Noise ‚ Possible sources of interference (elevators, wall material, types of rooms: open space, semi open Ratio). space, etc.).  Possible sources of interference (elevators, wall material, types of rooms: open space, semi open Materialspace, etc.). needed is described below:

‚ WIFIMaterial access needed point (Airlapis described 1131ag-e-k9 below: from Cisco). ‚  EkahauWIFI access Site Survey point 2.1(Airlap tool for1131ag-e-k9 taking sizes. from Cisco). ‚  LaptopEkahau that Site includes Survey a2.1 WIFI tool card. for taking sizes. ‚  PlansLaptop for areasthat includes to be controlled. a WIFI card.  Plans for areas to be controlled. The procedure has been integrated from the tasks described below: The procedure has been integrated from the tasks described below: ‚ Theoretical study of coverage or simulated by software  Theoretical study of coverage or simulated by software ‚ Study of actual coverage  Study of actual coverage ‚ Analysis of the study of actual coverage and design of WIFI network.  Analysis of the study of actual coverage and design of WIFI network. ‚ Measurements taken in the study of coverage of the new WIFI network.  Measurements taken in the study of coverage of the new WIFI network. ‚  ConclusionsConclusions and and writing writing the the document document FigureFigure 10 10 shows shows the the data data obtainedobtained inin the study of of system system coverage coverage prior prior to to the the installation installation of ofthe thesystem. system.

FigureFigure 10. 10.Power Power of of the the WIFI WIFI in in each each of of the the zones. zones.

The study of coverage is composed by the following phases: 1. Analysis of the study of coverage theoretical or simulated for software

Sensors 2016, 16, 1188 16 of 23

The study of coverage is composed by the following phases: 1. Analysis of the study of coverage theoretical or simulated for software 2. Analysis of the study of coverage a real study. The study of real coverage detected that the power of the WiFi signal was not as strong as the software was indicating. This problem was solved by approaching the points of access. The power of the tags must be ´75 dB as the Aeroscout manufacturer recommends. Figure 10 shows the power of the WiFi and the legend indicates the power of WIFI in each of the zones. From the study of the coverage system it is concluded that nine WIFI access points are needed, as shown in Table 10.

Table 10. Installed WIFI access points.

Number of Access Points Location Areas Controlled Hospital gateway/exit door Day Hospital gateway/exit door Cafeteria 7 Ground Floor Patients waiting room Medication administration room Medical consultation room 2 Floor 1 Pharmacy Service

In general, a RTLS system is not 100% accurate. In order to improve accuracy in localization, the manufacturer Aeroscout facilitates the possibility of installing exciters. The operation of these devices is simple: when an exciter detects a tag within their range of coverage it relays it to the location engine (associated with the location of the tag to the exciter) and thereby greatly improves the accuracy of the system in calculating location based solely on network WIFI access points. To enable this, the engineer should manually indicate in the available plans of the location engine the placement and location of the exciters. In order to conﬁgure the exciters, an initial survey must be carried out by the Aeroscout Exciter Detector BWH-3000-SV hardware and AeroScout Network Exciter Manager NEM-1000 software. This process aims to determine which is the most appropriate range for each of the covered exciters (for this model, between 0.5 and 12 m in diameter is possible). Table 11 shows the number and the location of the exciters installed to signiﬁcantly improve the accuracy of RTLS system.

Table 11. Installed exciters.

Number of Exciters Location Areas Controlled Hospital gateway/exit door Day Hospital gateway/exit door 4 Ground Floor Cafeteria Medication administration room 1 Floor 1 Pharmacy Service gateway/exit door

With the infrastructure detailed above, the RTLS system can calculate a position with an accuracy of 1 to 4 m. When the device detects a tag in an area controlled by exciters, it locates the tag in that area unmistakably until another exciter relocates it again in a new area. This corrects any errors in the network access points and allows the RTLS system to have, in most cases, an almost exact precision.

4.3.2. RFID Protocol in Day Hospital This work is focused in the prescription-validation-elaboration-dispensing-administration process of medication in the Day Hospital. A hub of information concerning traceability of the medication is Sensors 2016, 16, 1188 17 of 23 required from the point of prescription of medication by the physician until the nursing staff administer the medication to the patient. To achieve this we have used an application already in use in daily clinical practice within several hospital services [16] called SiMON (Intelligent Monitoring System), which is implemented in Java utilising the Informix database. This software allows users with an administrator profile to define a protocol primarily composed of a main registry and monitoring actions. Both are characterized by parameters (only in the case of the main registry the parameter structure will not change over the lifetime of the protocol) defined by the administrator that meet the needs of future users. One of the main advantages of SiMON is that it is integrated with the corporate applications SERGAS such as IANUS (responsible for EHR) or Laboratory (which manages different tests on patients). This means that the parameters of the main registry or monitoring actions can be data-managed on a daily basis in the clinical practice of the hospital and a duplication is not required, which improves the quality, efficiency, and safety of the patient care process. In this case the RFID protocol in the Day Hospital has been created with the following characteristics:

‚ Each patient has a unique principle record with invariable parameters: name and surname, NHR (Number of History Record), date of birth and age. ‚ Each main registry has monitoring actions and each one corresponds with a schedule for the administration of the medication made by the physician. ‚ Each monitoring action consists of six tabs with group information on each of the following threads: Date of administration, Prescription, Validation, Treatment Conﬁrmation, Medication Elaboration, and Conﬁrmation of the Administration.

Below are detailed the various tasks that can be carried out by different users under the professional proﬁle in the RFID protocol of the Day Hospital: Doctor:

‚ Prescribes medication electronically. ‚ Electronically schedules future administrations of the treatment. ‚ Records if the patient’s health is in proper condition for the administration of the drug.

Pharmacy staff:

‚ Validate the prescribed medication. ‚ Prepare elaboration orders for the nursing staff. ‚ Generate reports about monthly/yearly, etc. consumption for each medication, service, or both. ‚ Check the pending planning for a certain period of time.

Nursing staff in the Pharmacy Service:

‚ Have a consultant guide for the elaboration of the intravenous mixture. ‚ Visually print RFID tags. ‚ Identify unmistakably the intravenous mixture using RFID tag (records lot, date of expiry of its components, and the prepared medication). ‚ Bind the unique identiﬁer (UID) from the UHF tag and the NFC tag that make the dual RFID tag which identiﬁes intravenous mixtures. ‚ Record time of elaboration and shipping from the Pharmacy Service to the Day Hospital.

4.3.3. Tray RFID Real Time This application is developed and owned by the manufacturer responsible for the design of the RFID tray. It identifies the UID of the UHF tags of dual RFID labels deposited above it by sending an XML file with that information to a specific URL. It has been integrated with the RFID Day Hospital Sensors 2016, 16, 1188 18 of 23 protocol by web services so that the first time the RFID tray reads an intravenous mixture its delivery time has to be set in the Elaboration of Medication corresponding tracking tab, taking into consideration the administration date that was already scheduled.

4.3.4. Cart RFID Real Time This application is developed and owned by the manufacturer responsible for the design of the RFID transportation cart. It identifies the UID of the UHF tags of the dual RFID labels that are inside the cart, by sending an XML file with that information to a specific URL. It has been integrated with the RFID Day Hospital protocol by web services in such a manner that the first time RFID cart reads an intravenous mixture, its time of departure from the Pharmacy Service is set in the Elaboration of Medication corresponding tracking tab, taking into consideration the administration date that was already scheduled.

4.3.5. Configuration of USB Mode RFID Readers USB mode readers must be configured so that there is consistency in reading dual information from RFID labels in all devices available in different RFID systems. Two models were found (UHF and NFC) that are operated by a keyboard emulator so that further development is not necessary to implement their functionality. Both should read 16 characters from UID tags and in hexadecimal format. The configuration of both readers cannot easily be confused and is performed by a desktop application created by the manufacturer of the devices.

4.3.6. AndRFID The AndRFID application has been developed in the CHUAC IT Service. Its main objective is that nursing staff can accurately check that the correct medication prescribed to the patient will be administered in suitable conditions (route, pattern, infusion rate, lot number and expiration date of the medication, etc.). It has been implemented in Java with Android and the interface design is easy and intuitive so as to minimize the training time of future users and to ensure service efﬁciency.

4.3.7. Project Costs The costs of the infrastructure WIFI have been minimal because the network (net) WIFI was available in the hospitable center. In the following table the most significant costs are described. It is important to emphasize that one part of this work was financed through project PI10/02442 of the Institute of Health Carlos III (around 40%) and that another part was financed by the hospital.

4.4. Evaluation of the System The preparation phase lasted approximately four months and was necessary to engage the procedures of the Pharmacy Service, the Day Hospital, Rheumatology, and IT support. The meetings were organized every two weeks and in attendance were the heads of service and at least one representative of the professional profiles involved: a pharmacist specializing in hospital pharmacy, nursing staff from the Pharmacy, nursing staff from the Day Hospital, practitioners from Rheumatology, and software engineers from the R&D Systems Branch Information Systems from CHUAC. On 4 December 2014 the first active WIFI RFID tag was delivered to a patient. On 19 January 2016 a total of 2515 intravenous prepared mixtures and 285 patients are managed through this project. To evaluate the system, seven questionnaires were designed with one for each professional profile (patient, doctor, pharmacist specialising in hospital pharmacy, nursing staff in the day hospital, computer personnel, subdirector of hospital systems) involved in the development and practical use of the system under evaluation. Only simple questions were presented, only related to tasks with which the professionals are directly involved so that, with their experience, they are likely to respond more accurately. The thematic content of the questionnaires evaluates some indicators of the systems: Sensors 2016, 16, 1188 19 of 23 Sensors 2016, 16, 1188 19 of 23 At present, we are working on the evaluation of additional indicators such as Usability, Efficiency, and Suitability for Routine clinical practice. During the pilot test no important incidents Safety,happened. Traceability The of principal patients, incidents Traceability consisted of medication, in that the nursing Cost. We staff analyzed sent the in medication detail the prepared values of the answersfor the of 19 Day questionnaires Hospital before (0: the minimum doctor had level confirmed of satisfaction the perfect and state 5: maximum of health of level the patient. of satisfaction). It is The resultsnecessary of the to emphasize first phase that of evaluationduring the first indicates days an that average the values of six patients of all the forgot indicators the active are WIFI between tag 3.5 and 5RFID (see Figureat their 11home.).

5 4.5 4 3.5 3 2.5 Indicators 2 1.5 1 0.5 0 Safety Trace. Pat. Trace. Med. Cost

FigureFigure 11. 11.Global Global Values Valuesof of thethe analysed Indicators. Indicators.

At present,One of wethe first are workingagreements on was the to evaluation acquire the of mate additionalrial described indicators in Table such 12, astaking Usability, into account Efficiency, and Suitabilitythe volume for of Routinepatients expected clinical practice.to meet the During criteria the for pilot inclusion. test no Later, important the successive incidents meetings happened. mainly dealt with the following points: The principal incidents consisted in that the nursing staff sent the medication prepared for the Day Hospital beforeDetermine the the doctor new hadpatient confirmed course: Arrivals the perfect and Departures state of health from the of thehospital, patient. waiting It is area, necessary and to emphasizeCafeteria. that during the first days an average of six patients forgot the active WIFI tag RFID at their home. Elaboration of informed consent for patients.  Circuit of delivering, activating, configuring, and collecting active tags. One of the first agreements was to acquire the material described in Table 12, taking into account  Determine training sessions for each healthcare professional (two hours a day during a week at the volumethe of most). patients expected to meet the criteria for inclusion. Later, the successive meetings mainly dealt with the following points: Table 12. Cost of the Materials for the System and System Test. ‚ Determine the new patient course: Arrivals and Departures from the hospital, waiting area, Material Cost/Unit and Cafeteria. Android mobile phones with NFC (3 units) 150 euros ‚ Elaboration of informed consentUSB mode for UHF patients. reader (2 units) 200 euros ‚ Circuit of delivering, activating,USB mode configuring, NFC reader (2 and units) collecting active tags. 200 euros Printer (2 units) 3,000 euros ‚ Determine training sessions for each healthcare professional (two hours a day during a week at RFID Tray (1 unit) 3,000 euros the most). Software Aeroscout of RTLS Systems (1 unit) 18,327.11euros Laptop (1 unit) 700 euros Table 12.RFIDCost Transportation of the Materials Cart for(1 unit) the System and System 7,913.47 Test. euros RFID passive tags (500 units) 1 euro RFID AeroscoutMaterial WIFI active tags (200 units) Cost/Unit 70 euros Lanyards for the patient to carry the tags (200 units) 0.3 euros BagsAndroid with eurotaladro mobile phones for each with WIFI NFC active (3 tag units) (500 units) 150 0.01 euros euros USB mode UHF reader (2 units) 200 euros USB mode NFC reader (2 units) 200 euros Finally, there were a number of periodic tasks relating to active WIFI tags maintenance (for the Printer (2 units) 3,000 euros RFID cart and patients) that were assigned to IT support: RFID Tray (1 unit) 3,000 euros  ManagementSoftware of low battery Aeroscout alert ofin RTLSactive Systems WIFI tags (1 unit)(collection and 18,327.11 change). euros Laptop (1 unit) 700 euros RFID Transportation Cart (1 unit) 7,913.47 euros

RFID passive tags (500 units) 1 euro RFID Aeroscout WIFI active tags (200 units) 70 euros Lanyards for the patient to carry the tags (200 units) 0.3 euros Bags with eurotaladro for each WIFI active tag (500 units) 0.01 euros Sensors 2016, 16, 1188 20 of 23

Finally, there were a number of periodic tasks relating to active WIFI tags maintenance (for the RFID cart and patients) that were assigned to IT support: Sensors 2016, 16, 1188 20 of 23 ‚ ManagementSensors 2016, 16, 1188 of low battery alert in active WIFI tags (collection and change). 20 of 23 ‚ ConﬁgurationConfiguration of active WIFI tags in ﬁrstfirst time use (battery test, number of channels, frequency  Configuration of active WIFI tags in first time use (battery test, number of channels, frequency of transmission). of transmission). The start-up of this effort hashas notnot changedchanged thethe essentialessential functioningfunctioning ofof prescription-validation-prescription-validation- The start-up of this effort has not changed the essential functioning of prescription-validation- elaboration-administration process of medication to patients in the Day Hospital. The following elaboration-administrationelaboration-administration process process ofof medicationmedication to to patients patients in in the the Day Day Hospital. Hospital. TheThe following following describesdescribes the steps the steps and and summarizes summarizes the the main main cases casescases ofof us useee byby by health health health professionals, professionals, professionals, as seenas as seen seen in Figure in in Figure Figure 12: 12:12.

Figure 12. Cases of use by health professionals. Figure 12. Cases of use by health professionals. Figure 12. Cases of use by health professionals. If the physician prescribes a medication for the first time to a patient following the RFID protocol Iffor the Day physician physician Hospital, prescribes authorization a medication is needed from for the hospitalfi ﬁrstrst time commission. to a a patient patient If followingauthorized, following the the RFID RFIDtreatment protocol protocol for Day starts Hospital, and the authorizationphysician explains is needed how the from system the wo hospital rks through commission. informed consent,If authorized, authorized, and if the the patient treatment startsaccepts, and the the physician physician explains gives the how active the WI system FI tag from wo worksrks Aeroscout through to informed the patient. consent, and if the patient The physician binds the NHR to the tag MAC which localizes it in Mobile View, to later track accepts, the physician gives the active WIFIWIFI tag from Aeroscout toto thethe patient.patient. the patient in the system (see Figure 13). This means that in each of the administrations scheduled by The physician binds the NHR to the tag MAC which localizes localizes it it in in Mobile Mobile View, View, to later track the doctor, there is real time knowledge on the arrival and departure of the patient to and from the the patient in the system (see Figure 13). This means that in each of the administrations scheduled by the patienthospital in asthe well system as on(see his Figure or her 13). location This means in real that time in eachon each of the of administrations the controlled areas, scheduled i.e., by the doctor, administration there is room real timetimein the knowledgeknowledge Day Hospital, on cafeteria, the arrivalarrival waiting and room, departure etc. of the patient to and from the hospital asas well well as as on hison orhis her or location her location in real timein real on eachtime of on the each controlled of the areas, controlled i.e., administration areas, i.e., administrationroom in the Day room Hospital, in the cafeteria, Day Hospital, waiting cafeteria, room, etc. waiting room, etc.

Figure 13. Location in real time of the patient.

Sensors 2016, 16, 1188 21 of 23

Periodically, the physician programs future administrations of medication in the Date of Administration tab in the RFID protocol for the Day Hospital. Before the patient arrives at the hospital, the pharmacist has validated and elaborated the preparation orders of the medication prescribed to theSensors patient. 2016, In16, each1188 administration scheduled, the patient goes to the doctor to check if he or21 of she 23 is in good health for treatment; if so, the doctor notiﬁes the Pharmacy Service through the Treatment he or she is in good health for treatment; if so, the doctor notifies the Pharmacy Service through the Conﬁrmation tab, following the RFID protocol for Day Hospital. Treatment Confirmation tab, following the RFID protocol for Day Hospital. Pharmacy staff develop and unmistakably identify the intravenous mixture to be administered Pharmacy staff develop and unmistakably identify the intravenous mixture to be administered to the patient through the Medication Elaboration tab following RFID protocol for the Day Hospital to the patient through the Medication Elaboration tab following RFID protocol for the Day Hospital (see(see Figure Figure 14 14)) and and the the RFID RFID system system for for preparingpreparing thethe medication in in the the Pharmacy Pharmacy Service. Service. Later, Later, the the medicationmedication is is placed placed in in the the RFID RFID cart; cart; byby usingusing the RFID system system of of medication medication traceability traceability it can it can be be trackedtracked during during its its transport transport from from the the Pharmacy Pharmacy ServiceService to the Day Day Hospital. Hospital.

Figure 14. Traceability of the elaboration of the intravenous mixture. Figure 14. Traceability of the elaboration of the intravenous mixture. Finally, when the cart arrives to the Day Hospital, the orderly places the medication in the RFID trayFinally, to control when its thedelivery cart arrives and the to nursing the Day staff Hospital, administer the orderlythe medication places thethrough medication the RFID in system the RFID trayfor to administrating control its delivery medication and the to the nursing patient. staff This administer identifies the the medication patient by reading through his the or RFID her NHR system forand administrating reads the tag medication from the medication to the patient. and the This mobile identiﬁes application the patient by different by reading alerts. his It or also her confirms NHR and readsthat the the tag prescribed from the medication medication is and going the to mobile be ad applicationministered byto the different correct alerts. patient It alsoand conﬁrmsin suitable that theconditions prescribed (dose, medication route, pattern, is going infusion to be administered rate, expiration to thedate, correct etc.). patient and in suitable conditions (dose, route,The number pattern, of infusionpatients included rate, expiration increases date, monthl etc.).y as the objective is to cover the total number of Thepatients number who of have patients prescription included increasesmedications monthly that are as theconsidered objective high is to coverrisk and the totalcost numberand are of patientsadministered who have in the prescription CHUAC Day medications Hospital. that The are most considered important high incidents risk and detected cost and so arefar administeredhave been: inproblems the CHUAC in reading Day Hospital. the bar code The of mostthe MAC important tag (misdirection incidents in detected the reader), so farand haveerror been:in the location problems inof reading the attachment the bar code of the of RFID the MAC tags tagon intravenou (misdirections mixtures in the reader),prepared and by me errordical in personnel. the location All of of the attachmentthese have of been the RFIDprogressively tags on intravenous minimized as mixtures the lear preparedning curve by of medical the medica personnel.l staff has All improved. of these have It beenis important progressively to note minimized that the system as the learningis prepared curve to be of easily the medical extended staff to hasany improved.other service/treatment It is important prescribed in CHUAC. to note that the system is prepared to be easily extended to any other service/treatment prescribed in CHUAC. 5. Conclusions In conclusion, RFID technology has been successfully integrated in the process of prescription- validation-elaboration-dispensation-administration of drugs in the Pharmacy and Hospital CHUAC, significantly increasing patient safety by minimizing the possible occurrence of adverse events. As

Sensors 2016, 16, 1188 22 of 23

5. Conclusions In conclusion, RFID technology has been successfully integrated in the process of prescription-validation-elaboration-dispensation-administration of drugs in the Pharmacy and Hospital CHUAC, significantly increasing patient safety by minimizing the possible occurrence of adverse events. As seen above, RFID systems that work simultaneously in clinical practice have been developed and utilized successfully. These have varying and very different technical features: such as obtaining medication and patient tracking by designing a RFID cart and a RFID tray that unmistakably identifies patients and medication; but these features have been integrated with each other to a high standard of success. It should be underlined that this system and study has overcome one of the main difficulties inherent in this work: the fact that the design of its technical architecture features a combination of several operating frequencies (UHF control drugs in the car and RFID tray, NFC for administration by mobile phone) and several different energy sources for the tags (WIFI active, passive), all of which must function collectively. Importantly, in this work, we have solved some problems that are intrinsic to the nature of the technology such as readings on liquids in glass or plastic containers. It is possible to read 100% of the drugs labelled due to the strategic location in “Flag Mode” of passive tags and RFID that prevents interference with certain materials. To ensure the security of data stored on tags, the UID (unique identifier factory) has been used and is associated in the database to the prescription and clinical data of each patient. Another important element is that the location precision components manufactured by Aeroscout is accurate between 1 and 4 m in all controlled areas of the Pharmacy Service and Day Hospital. This study has concluded that the integration of RFID technology in the healthcare environment is economically viable, in particular for the selected scenario, considering the high risk characteristics of the medication and diseases for which these treatments are prescribed. It can be seen that RFID can significantly increase the quality of care received by patients during their care process in this scenario. Regarding immediate future work, the evaluation of the system by health professionals involved in their use in clinical practice is proposed, so as to enable improvements in the potential weak points detected.

Acknowledgments: Part of this work has been financed by project PI10/02442 of the Institute of Health Carlos III. The authors wish to thank the Hospital of A Coruña Rheumatology, Day Hospital, Pharmacy and Informatics departments for their cooperation. Author Contributions: All the authors contributed equally to the development of this work. Conflicts of Interest: The authors declare no conflict of interest.

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