Evaluation of a novel flow‐controlled syringe infusion pump for precise and continuous drug delivery at low flow rates: a laboratory study

AbstractThis work presents the improvements of an experimental setup for measuring ultra-low flow rates down to 5 nl/min. The system uses a telecentric CCD imaging system mounted on a high-precision, computer-controlled linear stage to track a moving liquid meniscus inside a glass capillary. Compared to the original setup, the lowest attainable expanded uncertainty at any flow rate has been reduced from 5.4% to 2%. In addition, the conformity with specification of three commercial micro-fluidic devices was evaluated using the new setup: one syringe pump, one implantable infusion pump and one thermal flow sensor. The flow sensor and the implantable infusion pump met the compliance criteria (coverage probability 95%). The syringe pump however, failed to meet the specifications at 5 nl/min and 10 nl/min. No assessment could be made at higher flow rates.

Download Full-text

Flow rate effect on partially modified potato starch microspheres formation process

Current Issues in Pharmacy and Medical Sciences ◽

10.2478/cipms-2020-0015 ◽

2020 ◽

Vol 33 (2) ◽

pp. 76-82

Author(s):

Roaa Mohammed Muneer ◽

Nizar Jawad Hadi ◽

Ali Al-Zubiedy

Keyword(s):

Drug Delivery ◽

Hydrogen Bonding ◽

Sodium Alginate ◽

Flow Rate ◽

Potato Starch ◽

Spherical Shape ◽

Tween 80 ◽

Continuous Phase ◽

Low Flow ◽

Flow Rates

AbstractNatural biopolymers are the most likely choice for biomedical applications, and starches can be considered the best materials for such applications. This comes from the fact of their natural origin and their high biodegradable behavior. Native starches have weak hydrogen bonding and a leaching behavior – making it a candidate for drug delivery application. Still, to make starch useful as a drug delivery carrier, this hydrogen bonding must be strengthened. In this work, native sweet potato starch was used, and the hydrogen bonding between starch molecules was enhanced by introducing glycerol as a hydrogen bonding source and sodium alginate (SA) as a thickener. This blend was tested by means of FTIR and DSC, and based on the test results, improved hydrogen bonding had taken place. Furthermore, potato starch microspheres were successfully produced at different flow rates. In the work, a microfluidic capillary device was harnessed to form microsphere generating total flow rates ranging between (0.00031 and 0.00054) cm3/sec. Herein, a starch/sodium alginate/glycerol mixture was used as a dispersed phase and PVA+tween 80 was used as continuous phase. At high flow rates (0.00062-0.00054) cm3/sec, the microspheres took an oval shape. At flow rates (0.00034-0.00048) cm3/sec, the microspheres took a spherical shape. At very low flow rate (0.00031) cm3/sec, the microspheres shell was weak and caused core oozing. In this work, starch microspheres were successfully formed with diameter ranging from (151-263) µm.

Download Full-text

Assessment of drug delivery devices

Biomedical Engineering / Biomedizinische Technik ◽

10.1515/bmt-2014-0138 ◽

2015 ◽

Vol 60 (4) ◽

Cited By ~ 8

Author(s):

Elsa Batista ◽

Nelson Almeida ◽

Andreia Furtado ◽

Eduarda Filipe ◽

Luis Sousa ◽

...

Keyword(s):

Drug Delivery ◽

Flow Rate ◽

Infusion Rate ◽

Low Flow ◽

Flow Rates ◽

Delay Response ◽

Start Up ◽

Set Up ◽

Drug Delivery Devices ◽

Funded Research Project

AbstractFor critical drug delivery, it is important to have a constant and well-known infusion rate delivered by the complete infusion set-up (pump, tubing, and accessories). Therefore, various drug delivery devices and accessories were tested in this article in terms of their infusion accuracy, start-up delay, response time, and dependency on the viscosity. These measurements were performed as part of the European funded research project MeDD. The obtained results show that the infusion accuracy of the devices is flow rate and accessory depended, especially for low flow rates. Viscosity does not have a significant impact on the flow rate accuracy.

Download Full-text

Metrology for drug delivery

Biomedical Engineering / Biomedizinische Technik ◽

10.1515/bmt-2014-0155 ◽

2015 ◽

Vol 60 (4) ◽

Cited By ~ 2

Author(s):

Peter Lucas ◽

Stephan Klein

Keyword(s):

Drug Delivery ◽

Drug Delivery System ◽

Delivery System ◽

Low Flow ◽

European Research ◽

Special Issue ◽

Research Project ◽

Flow Rates ◽

European Research Project ◽

Metrological Infrastructure

AbstractIn various recently published studies, it is argued that there are underestimated risks with infusion technology, i.e., adverse incidents believed to be caused by inadequate administration of the drugs. This is particularly the case for applications involving very low-flow rates, i.e., <1 ml/h and applications involving drug delivery by means of multiple pumps. The risks in infusing are caused by a lack of awareness, incompletely understood properties of the complete drug delivery system and a lack of a proper metrological infrastructure for low-flow rates. Technical challenges such as these were the reason a European research project “Metrology for Drug Delivery” was started in 2011. In this special issue of

Download Full-text

An innovative drug delivery system designed for very low flow rates: experimental and clinical evaluation

European Journal of Anaesthesiology ◽

10.1097/00003643-200406002-00105 ◽

2004 ◽

Vol 21 (Supplement 32) ◽

pp. 28

Author(s):

N. Lutter ◽

E. Kozma ◽

M. Richter ◽

J. Schuettler

Keyword(s):

Drug Delivery ◽

Drug Delivery System ◽

Delivery System ◽

Clinical Evaluation ◽

Low Flow ◽

Innovative Drug ◽

Flow Rates

Download Full-text

Assessment of the Use of Humidified Nasal Cannulas for Oxygen Therapy in Patients with Epistaxis

ORL ◽

10.1159/000514460 ◽

2021 ◽

pp. 1-5

Author(s):

Jingjing Liu ◽

Tengfang Chen ◽

Zhenggang Lv ◽

Dezhong Wu

Keyword(s):

Flow Rate ◽

Oxygen Therapy ◽

Preliminary Investigation ◽

Nasal Cannula ◽

Low Flow ◽

Antiplatelet Drugs ◽

Flow Rates ◽

The Past ◽

Oxygen Inhalation ◽

Significant Difference

Introduction: In China, nasal cannula oxygen therapy is typically humidified. However, it is difficult to decide whether to suspend nasal cannula oxygen inhalation after the nosebleed has temporarily stopped. Therefore, we conducted a preliminary investigation on whether the use of humidified nasal cannulas in our hospital increases the incidence of epistaxis. Methods: We conducted a survey of 176,058 inpatients in our hospital and other city branches of our hospital over the past 3 years and obtained information concerning their use of humidified nasal cannulas for oxygen inhalation, nonhumidified nasal cannulas, anticoagulant and antiplatelet drugs, and oxygen inhalation flow rates. This information was compared with the data collected at consultation for epistaxis during these 3 years. Results: No significant difference was found between inpatients with humidified nasal cannulas and those without nasal cannula oxygen therapy in the incidence of consultations due to epistaxis (χ2 = 1.007, p > 0.05). The same trend was observed among hospitalized patients using anticoagulant and antiplatelet drugs (χ2 = 2.082, p > 0.05). Among the patients with an inhaled oxygen flow rate ≥5 L/min, the incidence of ear-nose-throat (ENT) consultations due to epistaxis was 0. No statistically significant difference was found between inpatients with a humidified oxygen inhalation flow rate <5 L/min and those without nasal cannula oxygen therapy in the incidence of ENT consultations due to epistaxis (χ2 = 0.838, p > 0.05). A statistically significant difference was observed in the incidence of ENT consultations due to epistaxis between the low-flow nonhumidified nasal cannula and nonnasal cannula oxygen inhalation groups (χ2 = 18.428, p < 0.001). The same trend was observed between the 2 groups of low-flow humidified and low-flow nonhumidified nasal cannula oxygen inhalation (χ2 = 26.194, p < 0.001). Discussion/Conclusion: Neither high-flow humidified nasal cannula oxygen inhalation nor low-flow humidified nasal cannula oxygen inhalation will increase the incidence of recurrent or serious epistaxis complications; the same trend was observed for patients who use anticoagulant and antiplatelet drugs. Humidification during low-flow nasal cannula oxygen inhalation can prevent severe and repeated epistaxis to a certain extent.

Download Full-text

Effect of Tip Clearance on Suction Performance at Different Flow Rates in a Mixed Flow Pump

Volume 1B, Symposia: Fluid Machinery; Fluid-Structure Interaction and Flow-Induced Noise in Industrial Applications; Flow Applications in Aerospace; Flow Manipulation and Active Control: Theory, Experiments and Implementation; Multiscale Methods for Multiphase Flow; Noninvasive Measurements in Single and Multiphase Flows ◽

10.1115/fedsm2014-21207 ◽

2014 ◽

Author(s):

Yo Han Jung ◽

Young Uk Min ◽

Jin Young Kim

Keyword(s):

Performance Test ◽

Stokes Equations ◽

Flow Characteristics ◽

Tip Clearance ◽

Low Flow ◽

Tip Leakage Flow ◽

Mixed Flow ◽

Flow Rates ◽

Suction Performance ◽

Flow Pump

This paper presents a numerical investigation of the effect of tip clearance on the suction performance and flow characteristics at different flow rates in a vertical mixed-flow pump. Numerical analyses were carried out by solving three-dimensional Reynolds-averaged Navier-Stokes equations. Steady computations were performed for three different tip clearances under noncavitating and cavitating conditions at design and off-design conditions. The pump performance test was performed for the mixed-flow pump and numerical results were validated by comparing the experimental data for a system characterized by the original tip clearance. It was shown that for large tip clearance, the head breakdown occurred earlier at the design and high flow rates. However, the head breakdown was quite delayed at low flow rate. This resulted from the cavitation structure caused by the tip leakage flow at different flow rates.

Download Full-text

Experimental Investigation of Pressure Fluctuations on Inner Wall of a Centrifugal Pump

International Journal of Turbo and Jet Engines ◽

10.1515/tjj-2016-0078 ◽

2019 ◽

Vol 36 (4) ◽

pp. 401-410 ◽

Cited By ~ 2

Author(s):

Xiao-Qi Jia ◽

Bao-Ling Cui ◽

Zu-Chao Zhu ◽

Yu-Liang Zhang

Keyword(s):

Centrifugal Pump ◽

Flow Rate ◽

Pressure Fluctuation ◽

Pressure Fluctuations ◽

High Flow ◽

Low Flow ◽

Centrifugal Pumps ◽

Flow Rates ◽

Pressure Distributions ◽

Blade Passing Frequency

Abstract Affected by rotor–stator interaction and unstable inner flow, asymmetric pressure distributions and pressure fluctuations cannot be avoided in centrifugal pumps. To study the pressure distributions on volute and front casing walls, dynamic pressure tests are carried out on a centrifugal pump. Frequency spectrum analysis of pressure fluctuation is presented based on Fast Fourier transform and steady pressure distribution is obtained based on time-average method. The results show that amplitudes of pressure fluctuation and blade-passing frequency are sensitive to the flow rate. At low flow rates, high-pressure region and large pressure gradients near the volute tongue are observed, and the main factors contributing to the pressure fluctuation are fluctuations in blade-passing frequency and high-frequency fluctuations. By contrast, at high flow rates, fluctuations of rotating-frequency and low frequencies are the main contributors to pressure fluctuation. Moreover, at low flow rates, pressure near volute tongue increases rapidly at first and thereafter increases slowly, whereas at high flow rates, pressure decreases sharply. Asymmetries are observed in the pressure distributions on both volute and front casing walls. With increasing of flow rate, both asymmetries in the pressure distributions and magnitude of the pressure decrease.

Download Full-text