5.4 – Syringe/Infusion Pumps

Introduction to Syringe/Infusion Pumps

An infusion pump is a medical device that delivers fluids, such as nutrients and medications, into a patient’s body in controlled amounts. Infusion pumps are in widespread use in clinical settings such as hospitals, nursing homes, and in the home.

In general, an infusion pump is operated by a trained user, who programs the rate and duration of fluid delivery   a built-in software interface. Infusion pumps offer significant advantages over manual administration of fluids, including the ability to deliver fluids in very small volumes, and the ability to deliver fluids at precisely programmed rates or automated intervals.   They can deliver nutrients or medications, such as insulin or other hormones, antibiotics, chemotherapy drugs, and pain relievers.

There are many types of infusion pumps, including large volume, patient-controlled analgesia (PCA), elastomeric, syringe, enteral and insulin pumps.  Some are designed mainly for stationary use at a patient’s bedside.  Others, called ambulatory infusion pumps, are designed to be portable or wearable.

Because infusion pumps are frequently used to administer critical fluids, including high-risk medications, pump failures can have significant implications for patient safety. Many infusion pumps are equipped with safety features, such as alarms or other operator alerts that are intended to activate in the event of a problem. For example, some pumps are designed to alert users when air or another blockage is detected in the tubing that delivers fluid to the patient. Some newer infusion pumps, often called smart pumps, are designed to alert the user when there is a risk of an adverse drug interaction, or when the user sets the pump’s parameters outside of specified safety limits (see Figure 5.4.1).

Over the past several years, significant safety issues related to infusion pumps have come to FDA’s attention.   These issues can compromise the safe use of external infusion pumps and lead to over- or under-infusion, missed treatments, or delayed therapy.

From 2005 through 2009, FDA received approximately 56,000 reports of adverse events associated with the use of infusion pumps, including numerous injuries and deaths. During this time period, manufacturers conducted 87 infusion pump recalls to address identified safety concerns. Seventy of these recalls were designated as Class II, a category that applies when the use of the recalled device may cause temporary or medically reversible adverse health consequences, or when the probability of serious adverse health consequences is remote. Fourteen recalls were Class I – situations in which there is a reasonable probability that use of the recalled device will cause serious adverse health consequences or death. These adverse event reports and device recalls have not been isolated to a specific manufacturer, type of infusion pump, or use environment; rather, they have occurred across the board.

Although some adverse events may be the result of user error, many of the reported events are related to deficiencies in device design and engineering, which can either create problems themselves or contribute to user error.  The most common types of reported problems have been associated with software defects, user interface issues, and mechanical or electrical failures.

In 2010 the FDA announced three steps it would take to improve infusion pump safety.   These steps were to (1) increase user awareness, (2) proactively facilitate device improvements, and (3) publish new guidance for industry.

Watch

Video: Describes the basic function of a syringe/infusion pump.

To learn how to access the transcript for this video, see “YouTube transcript instructions (opens a new window)”

Common Troubleshooting Issues with Syringe/Infusion Pumps

Broken components

• The infusion pump may have been dropped or damaged during use, which may result in an over-infusion or an under-infusion if the pump continues to be used without being repaired.
• The plastic casing of an insulin pump, although promoted as waterproof, is prone to cracking, allowing water to enter the case and to cause the pump to malfunction.
• Slight misalignment of tubing places stress on the pump door, resulting in eventual cracking of pump case. See the photos below.

Fire, sparks, charring, or shocks:

• The user plugs in or unplugs the device from an electrical outlet and receives a shock, and/or sparks are seen.
• A burning smell or flames are noted on the infusion pump.

Battery failures:

• A design issue causes over-heating of the battery and leads to premature battery failure.
• A patient returns from ambulating and forgets to plug in the infusion pump. The infusion pump alarms with a low battery message, but the speaker volume is set too low, and the alarm goes unnoticed. The infusion pump powers off after the battery is depleted.
• The battery is not replaced during the recommended end of life routine maintenance.

Alarm errors:

• The infusion pump fails to generate an audible alarm for a critical problem, such as an occlusion (e.g., clamped tubing) or the presence of air in the infusion tubing.
• The infusion pump generates an occlusion alarm in the absence of an occlusion.

Software problems:

• A software error message is displayed, stating that the pump is inoperable. This occurs in the absence of an identifiable problem.
• The infusion pump interprets a single keystroke as multiple keystrokes (a problem called a “key bounce”). For example, the user programs an infusion rate of 10 mL/hour, but the device registers an infusion rate of 100 mL/hour.

Watch

Video: While the following video is quite long (> 30 minutes), it does provide detailed descriptions of maintenance and troubleshooting of syringe pumps.

To learn how to access the transcript for this video, see “YouTube transcript instructions (opens a new window)”

The following content depicts a flow chart for troubleshooting and repair of an infusion device.

https://bmet.ewh.org/server/api/core/bitstreams/7e70a1bb-9a3a-4460-bd93-5cc95300e913/content (Page 23)

Figure 5.4.1 Troubleshooting and repair of an infusion pump