The Influences Of Auxiliary Materials On The Performance Of Injection Pump

Injection is the most common clinical medical treatment, and drug injection with injection pump has gradually become an important means in many hospital. The trace injection pump can automatically and precisely pump drugs into the veins at a constant speed to control the effective drug concentrations in the blood, and reduce the workload of nurses. Therefore, injection pump was popularize gradually into many hospitals, especially in pediatric, geriatrics, and Intensive Care Unit(ICU)In domestic large general hospital, the allocation of injection pump to the beds is 1:4.Although injection pump greatly improved the clinical quality, there are safety risks and problems of quality control in the use of it.. According to the data provided by the Center for Drugs and Medical Devices Adverse Reactions Monitoring in China, the reported adverse reactions in the use of infusion pump ranks 5 in that of all medical instruments.. Therefore, research and analysis on the safety and quality control injection pump is not only an essential part of the hospital medical quality management, but an important basis to improve the level of the injection pump manufacturing.The theory and technology of injection pump represented the development of engineering design, therefore, most researches from clinical medical engineering expertsin many hospitals focused their studies on the engineering features of injection pump, and hope to improve the safety and quality control of it through the mandatory index form governments or industries, or the performance tests in laboratories. However, there are only one third adverse accidents in medical practices are induced by electrical faults or the accuracy of the device itself. Therefore, exploration and discovery the influence factor outside the injection pump itself is an important strategy to improve the quality assurance system and risk control.In the current study, we employed the popularly used injection pump in clinical practice and the world famous quality control equipment, by determining the deviation rates of the speed and total volume of injection, the reliability of block alarm, and the accuracy of emptying alarm, we investigated the effects of the syringes and pressure pipes on the performance of injection pump. Our data will provide important theory basis for increase the performance of injection pump in clinical practices, and for improving the engineering design of injection products.Objective: The aim of this study is to determine and analysis the changes of the speed and total volume of injection, the reliability of blocking alarm, and the accuracy of emptying alarm of injection pump when using different-sized syringes and pressure pipes, clarify the effects of these auxiliary materials on the performance of the injection pump, and explore the important factors that contribute to the errors from injection and clinical risk. The findings of this study will provide theory basis for control the risks in the using of injection pump, and improve the operational skill of it.Methods: Establish the injection pump infusion model with different-sized syringes and pressure pipes. 1. The speed deviation test 1) Create a closed circuit with an injection pump, a performance tester(Fluke IDA- 4 Plus), a pressure pipe, and a syringe. 2) The combination of syringes and pressure pipes are: 10 ml syringe + 80 cmpressure pipe, 20 ml syringe + 80 cm pressure pipe, 50 ml syringes + 80 cm pressure pipe, 10 ml syringe + 120 cm pressure pipe, 20 ml syringe + 120 cm pressure pipe, 50 ml syringe + 120 cm pressure pipe. The syringes were filled with physiological saline when connected to the injection pump. 3) The flow rate of the injection pump were set up as follows: 5, 10, 15, 20, 25, 30, 35, 40, 45, 50, 100, 200, and 300 ml/h. 4) Read the Fluke IDA- 4 Plus tester 10 times in each test, averaging and record the numbers. 5) Draw the speed deviation curves according to the data, 2. The total injection deviation test 1) Create a closed circuit with an injection pump, a Fluke IDA- 4 Plus tester, a pressure pipe, and a syringe. 2) The combination of syringes and pressure pipes are: 10 ml syringe + 80 cm pressure pipe, 20 ml syringe + 80 cm pressure pipe, 50 ml syringes + 80 cm pressure pipe, 10 ml syringe + 120 cm pressure pipe, 20 ml syringe + 120 cm pressure pipe, 50 ml syringe + 120 cm pressure pipe. The syringes were filled with physiological saline when connected to the injection pump. 3) The total volume of the injection were set up as follows: 10 ml syringe(1, 2, 3, 4, 5, 6, 7, 8, 9, and 10 ml), 20 ml syringe(2, 4, 6, 8, 10, 12, 14, 16, 18, and 20 ml), 50 ml syringe(5, 10, 15, 20, 25, 30, 35, 40, 45, and 50 ml). 4) Read the Fluke IDA- 4 Plus tester 10 times in each test, averaging and record the numbers. 5) Draw the speed deviation curves according to the data. 3. The blocking alarm reliability test 1) Create a closed circuit with an injection pump, a Fluke IDA- 4 Plus tester, a pressure pipe(with a triple valve), and a syringe. 2) The combination of syringes and pressure pipes are: 10 ml syringe with 80 cm pressure pipe; 20 ml syringe with 80 cm pressure pipe, 50 ml syringe with 80 cm pressure pipe, 10 ml syringe with 120 cm pressure pipe, 20 ml syringe with 120 cm pressure pipe,50 ml syringe with 120 cm pressure pipe. The syringes were filled with physiological saline when connected to the injection pump. 3) The flow rate of the injection pump were set up as follows: 5, 10, 20, 30, 50, 100, 150, 200, and 300 ml/h, respectively. 4) Close the triple valve, and at the same time start the timer. 5) Read the timer when hearing the alarm, Repeat 10 times in each test, averaging and record the numbers. 6) Draw the speed deviation curves according to the data. 4. Emptying alarm accuracy experiment 1) Create a closed circuit with an injection pump, a Fluke IDA- 4 Plus tester, a pressure pipe(with a triple valve), and a syringe. 2) The combination of syringes and pressure pipes are: 10 ml syringe with 80 cm pressure pipe; 20 ml syringe with 80 cm pressure pipe, 50 ml syringe with 80 cm pressure pipe, 10 ml syringe with 120 cm pressure pipe, 20 ml syringe with 120 cm pressure pipe, 50 ml syringe with 120 cm pressure pipe. The syringes were filled with physiological saline when connected to the injection pump. 3) The flow rate of the injection pump were set up as follows: 5, 10, 20, 30, 50, 100, 150, 200, and 300 ml/h, respectively. 4) Start the timer as hearing the emptying alarm(this equipment starts alarm 3 min before the emptying). 5) Inform work equipment, record a stopwatch readings. Each group of tests averaged 10 times, and record. Read the timer when the injection pump was empty. Repeat 10 times in each test, averaging and record the numbers. 6) Draw the speed deviation curves according to the data.Results: 1. The influence of auxiliary materials on the injection speed 1) The syringes: The impact of syringes on the injection pump speed is 50 ml <20 ml <10 ml. Namely, the influence of larger-sized syringes on the precision of injection rate is less than that of the smaller-sized ones.2) The pressure pipes: The impact of pressure pipes on the injection pump speed is that the 80 cm one slightly smaller than that of the 120 cm one, suggesting that the influence of the longer pressure pipe on the precision of injection rate is bigger than that of the shorter one. 2. The influence of auxiliary material on the total volume of injection 1) The syringes: The impact of syringes on the total injection volume is 50 ml <20 ml <10 ml, indicating that the influence of larger-sized syringes on the total volume of injection is less than that of the smaller-sized ones. 2) The pressure pipes: The 80 cm one has a slightly smaller influence on the total volume of injection than that of the 120 cm one, suggesting that the influence of the shorter pressure pipe on the total volume of injection is less than that of the longer one. 3. The influence of auxiliary materials on the blocking alarm 1) The syringes: Following the blocking of the injection, the 10 ml syringe group alarmed first, and the 50 ml syringe group is the latest system to alarm, indicating that the when using larger-sized syringe, the blocking alarm delayed longer time, and the reliability of the blocking alarm was worse. 2) The pressure pipes: Following the blocking of the injection, the 80 cm pressure pipe group alarmed earlier than the 120 cm pressure pipe group, suggesting that longer cm pressure pipe resulted in more delayed alarm and worse reliability of the system. 4. The influence of auxiliary materials on the emptying alarm 1) The syringes: When the flow rates are low, the size of the syringes has no significant influence on the precision of emptying alarm. While the flow rates are fast, the influence of different-sized syringes on the precision of emptying alarm is 50 ml <20 ml <10 ml. 2) The pressure pipes: The size of the pressure pipes has no significant influence on the precision of emptying alarm.Conclusion: 1. In this study, the data demonstrated that different-sized syringes and pressure pipes have certain impact on the precision of both the speed and total volume of the injection. Insome extreme conditions, the maximum deviation can be approximately 15%, which much higher than the quality control standard of injection pumps(±2.5%). This kind of deviation may have adverse impact on clinical quality. The current data suggested that we can choose larger-sized syringes and shorter pressure pipes in the injection with the pump; on the other hand, the flow rate can influent the precision of the injection pump as well, i.e. the precision of the injection pump will drop when the flow rate is high or very slow. Therefore, aside of the auxiliary materials, the appropriate injection schemes are needed. 2. The reliability of the blocking alarm has its limitations. When the injection pump was blocked, the delay of the alarm(min) could be about 60/ the initial flow rate(V), indicating that slower flow rate resulted in longer delay of the alarm. 3. When the flow rates were high, the size of the syringes could alter the precision of the emptying alarm, and smaller-sized syringes resulted in worse precision of the system. The size of the pressure pipes has no significant influence on the precision of emptying alarm.