Malfunctions of Non-Electrical Infusion Pumps

An Evaluation of Cases Reported to the German Federal Institute for Drugs and Medical Devices

Non-electrical infusion pumps (neIPs) are used to infuse smaller volumes over a defined period of time. There are two types of neIPs: elastomeric pumps and mechanical pumps with a spring mechanism. NeIPs are used to infuse antibiotics, analgesics or cytostatics in both outpatient and inpatient settings. Serious incidents (SIs) occurring with the use of medical devices, such as neIPs, must be reported to the German Federal Institute for Drugs and Medical Devices (BfArM) where they are recorded and evaluated on a centralized basis. The legal basis is the European Medical Device Regulation (EU) 2017/745 (MDR) (1) and Medical Devices User Reporting and Notification Ordinance (MPAMIV) (2). By reporting such cases, rare risks and any necessary measures can be identified.

The aim of this study is to provide a summary of the reported incidents which occurred with the use of neIPs and to highlight potential risks relevant to clinical practice.

Methods

All neIP-related notifications recorded in the period from 1 January 2017 to 31 December 2022 and the malfunctions described therein (consequences of device defects, user errors) were evaluated retrospectively in order to determine whether there is an unacceptable risk associated with the future use of the device under investigation; the evaluation was based on reports from manufacturers or authorized representatives, users, operators and patients, reports from other European authorities, external expert opinions, as well as insights published in the scientific medical literature. The data was analyzed using the BfArM’s vigilance database. As the data is from a spontaneous reporting system, a descriptive statistical analysis was carried out due to the diversity of the individual reports. We do not include the names of manufacturers and products in this article.

The malfunctions described in the reports were identified and summarized (Table 1). Actual and potential harm to patients was assessed; an injury was classified as serious if the patient required treatment due to the incident.

Table 1

Non-electrical infusion pump malfunctions and frequencies

Results

During the observation period, 301 reports were recorded. The majority of the reports were submitted by manufacturers or their distributors (62%).

A total of eight different device-related malfunctions were reported (Table 1). The effects on patients were predominantly of a minor nature (n = 279) or no harm was reported (n = 4). In five cases, the harm to the patients led to hospitalization or an extended hospital stay. Of these, three cases were presented as examples (Table 2).

Table 2

Case studies of serious harm to patients

The misdosing incidents were examined thoroughly. In the majority of cases, the neIP was emptied too fast. In two cases, the infusion rates were up to more than 250% of the nominal flow rate specified by the respective manufacturer, resulting in overdosing of the drug and drug-specific side effects (Table 2). In 24 reported cases, neIP emptying was delayed or did not occur at all. In one of these cases, the patient, who had not received adequate treatment, had to be admitted to hospital.

Discussion

The use of neIPs can be regarded as an established and safe method of infusion therapy. In this article, we highlight (potential) malfunctions common to all comparable pumps. It is impossible to comment on the number of unreported serious incidents and the frequency of malfunctions.

The frequencies of the malfunctions (Table 1) correspond to previously published rates (3). Manufacturers specify various possible risks for patients and users associated with leaks: infections, bleeding, air embolism, injury to the skin. None of these possible risks were reported during the study period. Since it is usually not difficult to identify a leak, it is very likely that countermeasures can be taken in good time.

The flow-time diagram of elastomeric infusion pumps is not linear (3). The instructions for use do not make this sufficiently clear at times; misdosing can occur if the prescribing doctor, assuming a linear flow-time pattern, orders only partial filling of the reservoir.

In the event of misdosing, significant over-infusion can occur in individual cases, even if the neIP was—according to the manufacturer—free of defects and used correctly. Since neIPs lack alarm functionality, misdosing can remain undetected. Incidents of this type have already been published (4). In some cases, the instructions for use are not exhaustive with regard to the “misdosing” malfunction. The German Federal Institute for Drugs and Medical Devices then recommended that the respective manufacturer improve the instructions for use to adequately describe the risks associated with neIPs. Under-dosing can be due to crystallization of the drug, as such crystals can damage the flow regulators of the pumps (5). Especially in the outpatient setting, prescribing doctors should advise their patients to regularly check whether the administration is running without signs of malfunction.

Consequences for hospitals and practices

• In the manufacturing and labeling process, possible risks must be accounted for and specified in the instructions for use.
• Users must align the accuracy of neIPs with the medication to be administered. They must be familiar with the functional principle and performance limits of neIPs already before the infusion. During the infusion, it should be regularly checked whether the administration is running without signs of malfunction.
• If serious incidents occur, the BfArM must be notified so that risks can be identified and minimized.

Eberhard Munzert, Anja Jacobshagen

Conflict of interest statement
The authors declare that no conflict of interest exists.

Manuscript received on 19 December 2023; revised version accepted on 18 April 2024.

Cite this as:
Munzert E, Jacobshagen A: Malfunctions of non-electrical infusion pumps—an evaluation of cases reported to the German Federal Institute for Drugs and Medical Devices. Dtsch Arztebl Int 2024; 121: 541–2. DOI: 10.3238/arztebl.m2024.0082

References

1. Verordnung (EU) 2017/745 des Europäischen Parlaments und des Rates vom 5. April 2017 über Medizinprodukte, zur Änderung der Richtlinie 2001/83/EG, der Verordnung (EG) Nr. 178/2002 und der Verordnung (EG) Nr. 1223/2009 und zur Aufhebung der Richtlinien 90/385/EWG und 93/42/EWG des Rates (Medizinprodukteverordnung, MDR).

2. Verordnung über die Meldung von mutmaßlichen schwerwiegenden Vorkommnissen bei Medizinprodukten sowie zum Informationsaustausch der zuständigen Behörden (Medizinprodukte-Anwendermelde- und Informationsverordnung – MPAMIV).

3. Ackermann M, Maier S, Ing H, Bonnabry P: Evaluation of the design and reliability of three elastomeric and one mechanical infusers. J Oncol Pharm Practice 2007;13: 77–84.

4. Remerand F, Vuitton AS, Palud M, et al.: Elastomeric pump reliability in postoperative regional anesthesia: a survey of 430 consecutive devices. Anesth Analg 2008; 107: 2079–84.

5. Corbrion V, Crauste-Manciet S, Allain P, Brossard D: Precipitation of fluorouracil in elastomeric infusers with a polyisoprene reservoir and in polypropylene syringes with an elastomeric joint. Am J Health Syst Pharm 1997; 54: 1845–8.