Functional design of RFID-based wireless nursing information system and its hardware system implementation

1 Introduction

Due to the limitation of technology and objective conditions, hospitals have long adopted various measures but have not been able to effectively reduce the occurrence of medical errors. In addition to having a bad impact on the reputation of medical institutions, medical errors also bring irreparable losses to patients and huge economic losses.

There are three steps from seeing a doctor to receiving treatment: the doctor examines the patient and makes a preliminary diagnosis before issuing a medical order; the nurse copies the order onto the infusion or treatment card and prepares to execute it; and the nurse implements the treatment plan. Each of these three steps is crucial. There must be no negligence, otherwise it will lead to medical errors. Errors in medical order information can be reflected in the hospital information system, and most of these errors can be discovered and corrected before the nurse executes the order. However, at present, the process from issuing to executing medical orders is an open-loop process. The medical orders issued by doctors are well documented in the information system, but there is no objective and real-time record of who executes the orders and when they are executed. The method of verifying the patient's identity is also too simple. The traditional "three checks and seven comparisons" method is not ideal for implementation, and there is a hidden danger of medical errors. Medical errors such as taking the wrong medicine, getting the wrong injection, and even performing the wrong operation often occur.

With the development of wireless network technology and radio frequency identification technology (RFID), combining the two can effectively prevent and avoid medical errors. With the support of wireless network technology and RFID technology, real-time inspection and confirmation of each step in the execution of medical orders can be achieved, and the unique identification of patient identities, drugs, blood bags, etc. can be completed. This will play a huge role in ensuring patient safety, effectively improving medical quality, and reducing medical errors.

This paper implements a wireless nursing information system based on RFID design. By deploying wireless networks in wards, patients wear RFID tags, and attach RFID tags to medicines and blood bags, nurses can directly collect and enter patient information through PDA handheld computers, such as: who executes the doctor's orders, when the doctor's orders are executed, the patient's physiological indicators, nursing conditions (medication, temperature measurement times, diaper changes, feeding times), etc. The IP-PHONE connection has a calling function, which can effectively ensure that hospital staff can quickly and accurately identify patients at any time. The patient tag can also prevent being replaced or removed at will, ensuring the uniqueness and correctness of the tag object. The system can effectively realize the closed-loop control of the information of the entire process of doctor's order execution, prevent and avoid the occurrence of medical errors, and thus ensure the safety of patients.

2 Introduction to RFlD Technology

RFID (Radio Frequencv Identification) is a radio frequency identification that uses spatial electromagnetic induction or electromagnetic propagation to communicate, and realizes energy transfer and data transmission according to the timing relationship within the communication link, thereby achieving non-contact target identification and tracking.

The basic working method of the RFID system is to install the RFID tag on the object to be identified (paste, insert, wear, implant, etc.). When the identified object enters the reading range of the RFID reader, a wireless communication link is established between the tag and the reader. The tag sends its own information to the reader, such as the tag number and the data stored in the tag. The reader receives and decodes this information, and then transmits it to the background computer for processing, thereby completing the entire information processing process.

RFID does not require a wired reader, and the RFID tag has another function, which is to allow the information on the tag to be updated. The RFID reader can scan multiple tags at the same time, and each barcode must be read one by one by the corresponding barcode scanner; a linear barcode can only hold 10 to 20 characters of data. In contrast, the RFID reader is not limited by storage capacity and can store thousands of characters of data: In addition, the RFID tag can be wiped with alcohol, which effectively avoids the barcode from being unable to be read and losing its function when used in a humid environment or when it is contaminated by blood, worn, etc., making it more suitable for use in the medical industry.

3 Overall design of wireless nursing information system based on RFID

3.1 Schematic diagram of working environment

The working environment of the hospital digital RFID-based wireless nursing information system is shown in Figure 1. A wireless LAN is deployed in the ward, and a wireless AP (Access Point) is deployed according to the working range of the PDA. The patient wears an RFID tag belt, and the nurse carries a PDA with an RFID reading function. Information is exchanged with the HLS through the wireless network. The nurse determines the patient's identity based on the patient's tag, and at the same time, confirms the medicine when executing the doctor's order, and enters the doctor's order by who, when the doctor's order is executed, and the patient's vital signs data into the HLS through the PDA. At the same time, an access control system is installed in the ward, and the patient's entry and exit of the ward can be automatically reflected on the nurse station for easy management.

Figure 1 Design of working environment of wireless nursing information system based on RFlD

3.2 System overall structure

The system operating environment is Windows Mobile Server 5.0. A CF card RFID reader is installed on the PDA. The data on the tag is transmitted to the nursing information system through the driver program to realize the uniqueness confirmation of patients and drugs. The nursing information system connects to the HLS database through the Oracle ODBC driver program to realize data interaction, which is realized through the wireless network at the link layer. The nursing information system software consists of patient management, drug management, doctor's order processing, data management, knowledge base query and call modules. The overall structure of the RFID-based wireless nursing information system is shown in Figure 2.

Figure 2 The overall structure of the wireless nursing information system based on RFlD

3.3 Functional Design

Wireless nursing information system has the following functions

(1) Ability to scan RFID tags to uniquely identify the patient and the corresponding drug information.

(2) Be able to complete the patient's admission, discharge, transfer, department transfer, bed change and corresponding cancellation operations, and be able to query the patient's flow status.

(3) Enter and query test results, enter patient vital signs information (such as blood pressure, temperature, pulse, etc.), enter nursing information and diagnosis information on the medical record homepage, etc.

(4) Ability to complete operations such as entering, proofreading, and cancelling medical orders, enter medical order pricing items, query and process medical orders according to patients, and enter medicine placement.

(5) Implement patient call module and WI-based IP-PHONE function to facilitate information exchange between nursing staff.

(6) Realize knowledge base query and provide nursing staff with the best channel to obtain nursing knowledge and technology accurately, quickly, conveniently and flexibly, which can meet the knowledge needs of the majority of nursing staff and thus better serve the health of patients.

(7) Data management provides data backup and synchronization functions to ensure data security.

4 Implementation of wireless nursing information system based on RFID

4.1 Hardware System Implementation

The hardware system of the RFID-based wireless nursing system mainly includes the following four parts:

(1) CF card RF1D tag reader, model number is Compact Flash Reader KD8, supports IS014443A(B), IS015693 standards;

(2) PDA, model: HP iPAQ hx249Oc, running Windows Mobile 5.0:

(3) Wireless access point AP, model GIGABYTE GN-A11G, protocol IEEE 802.11802.11b:

(4) RFID label printer, model: Intellitag PM4i, operating frequency: 1356 MHz, supporting IS0 15693 standard.

4.2 Software System Implementation

The software implementation of the wireless nursing system based on RFID includes database and application software implementation, in which the database directly uses the relevant tables in the "Junwei No. 1" HIS database, including the patient master index, doctor's order table, price table, etc. The tables that need to be added are the comparison table between RFID tags and patient ID numbers in the HIS database and the comparison table between drug RF1D tags and doctor's orders.

The application software uses Microsoft.Net Framework 3.5 SDK. The development language is C#. The development environment is Microsoft Visual Studio 2008. The Sman Device CAB Project template is used. The software flow is shown in Figure 3.

In the process, first log in and select the function. Then complete the monitoring of the whole process of executing the doctor's order according to the selected module, or select the IP-PHONE function based on WIFI. If you want to realize information query, enter the nursing knowledge expert system. After all operations are finally completed, log out of the system.

5 Conclusion

This paper implements a wireless nursing information system based on RFID, realizes the correct identification of patient identity and drugs, realizes the closed-loop execution of doctor's orders, and effectively prevents and avoids the occurrence of medical errors. The next step of research should focus on solving the wireless network security in the hospital, the information security of RFID itself, and the protection of patient privacy data.