The flow Rate Accuracy of Elastomeric Infusion Pumps After Repeated Filling

Abstract

Background:One of the frequent applications of elastomeric infusion pumps is postoperative pain management. In daily practice, the disposable pumps get refilled with modified medication combinations in the successive days; although, the accuracy of infusion rates is unknown to clinicians.Objectives:Our aim was to evaluate the effect of repeated filling on the delivery rate accuracy of an elastomeric pump available in our market.Materials and Methods:We examined 10 elastomeric infusion pumps (BOT-802, Nanchang Biotek Medical Device Company, China) with 100 mL capacity and nominal flow of 5 mL/h. Each pump was filled for three times, accounting for 30 series of experiments. A microset scaled in mL was used to measure the pump deliveries. Flow profile and reliability of infusion rate were analyzed after repeated use.Results:The mean flow rate in the three series of measurements showed a gradual increase; however, the difference was not statistically significant (5.01 ± 0.07 vs. 5.03 ± 0.06 vs. 5.06 ± 0.08 mL/h; P = 0.81). The percentage of the flow rate error (deviation from 5 mL/h ± 15%) was 100% in the first and second hours of infusion, 96% in the third hour, 60% in the 20th hour and zero percent in the rest of the infusion time.Conclusions:This study indicated that the delivery rate accuracy of elastomeric infusion pumps is preserved after repeated usage. These laboratory findings suggested that elastomeric pumps could be safely refilled in the successive days to provide postoperative analgesia.

Stability of vincristine sulfate, doxorubicin hydrochloride and etoposide phosphate admixtures in polyisoprene elastomeric pump supporting transition of the EPOCH regimen to outpatient care

“…The temperature of the solution in the elastomeric infusor on a patient has not been previously reported although some studies showed that most manufacturers calibrated the pumps at 31-32 C to simulate the expected normal skin temperature, 20,21 mainly for the concern of temperature-dependent infusion rate. Here we carefully designed and measured the change of temperature of solutions inside the infusor during 24 h period worn by different volunteers and report the range measured including the highest temperature of 33.5 C which was lower than this evaluated temperature for stability studies of 35 C, demonstrating its validity.…”

Newer drug delivery systems in anesthesia

“…The driving pressures in these pumps are from 260 to 520 mmHg, and the infusion rates can vary from 0.5 to 500 ml/h. [ 66 ] The delivery rates are limited to the set values due to the presence of flow restrictors. The variable rate infusor can be adjusted to deliver 5, 7, or 12 ml/h drug, whereas the fixed infusors are designed to deliver 1.5, 2, 5, 7, and 12 ml/h of the drug volume.…”

Elastomeric pump malfunction resulting in over-infusion of local anesthetic

“…Elastomeric pumps are particularly popular due to their ability to be refilled, low cost, portability, independence from a power supply, disposability, as well as high patient satisfaction. 3–5 However, it has been suggested that these pumps may deliver inconsistent volume which could lead to inadequate analgesia or unintended side effects. 6,7 Such disadvantages can be caused by a multitude of factors such as temperature changes, viscosity of infused fluid, and even the height of the elastomeric pump relative to the catheter site.…”