Does New FDA Oversight Include Disposable Pain Pumps?
I am still a bit confused as to whether the new oversight regime the FDA announced yesterday applies to the disposable local anesthetic infusion surgically-implanted pumps that are my focus in this blog.
Reading the New York Times article on the announcement led me to think these devices might be excluded, as it focuses on IV-implanted, programmable devices used to provide insulin, chemotherapy, and pain medications (but patient-controlled). There have been over 56,000 adverse events and 710 deaths involving these devices in the past 5 years. These are truly staggering numbers. Regarding the types of problems reported, the FDA Press Release indicates: The most common types of reported problems have been related to:
* software defects, including failures of built-in safety alarms;
* user interface issues, such as ambiguous on-screen instructions that lead to dosing errors; and
* mechanical or electrical failures, including components that break under routine use, premature battery failures, and sparks or pump fires.
Failures of infusion pumps have been observed across multiple manufacturers and pump types. The FDA says that many of the reported problems appear to be related to deficiencies in device design and engineering.
I saw nothing about shoulder chondrolysis or other injuries from local anesthetics. So far, all of this sure seemed outside the scope of pain pumps.
The next step up in document complexity is the FDA's White Paper on its Infusion Pump Improvement Initiative. I read "In general, an infusion pump is operated by a trained user, who programs the rate and duration of fluid delivery through a built-in software interface" and it confirms my initial belief. However, then among the pump mechanisms elastomeric is listed and this is one of the most common types for disposable pain pumps. Finally, at the end of the paper I see among the footnotes: 1 This document does not pertain to implanted infusion pumps, which are surgically placed in the body. Okay, now I'm pretty sure this significant announcement doesn't apply to the devices with which I'm familiar. However, there are several additional documents the FDA has included and, for completeness sake, I read on.
The letter to infusion pump manufacturers from Jeffrey E. Shuren, Director of the FDA's Center for Devices and Radiological Health (CDRH) also focuses on software, design, human factors, and manufacturing problems.
There's detailed information about CDRH's software research on infusion pumps. I had no idea the FDA has a software engineering laboratory.
Ultimately, there's the agency's Guidance for Industry and Staff regarding 510(k) Pre-Market Notification Submissions. This is a draft document (34 pages in PDF form) which will be entering a 90-day comment period. When complete it will replace the Guidance on the Content of Premarket Notification [510(k)] Submissions for External Infusion Pumps, issued March, 1993.
My confusion was finally resolved (I think) by reading the Scope section of this document. It makes clear that all infusion pumps addressed by 21 C.F.R. 880.5725 will be covered by the new guidelines. This includes numerous types of devices including all Elastomeric Infusion Pumps (products coded MEB), and excludes only the following: gallstone dissolution pumps (MHD), opthalmic infusion pumps (MRH), and analytical sampling infusion pumps (LZF). Just to be sure, I double-checked the most recent 510(k) Submission for the On-Q Painbuster, which confirms the same regulation (880.5725) and product code (MEB).
So, it does indeed look like I-Flow, Stryker and company will have to learn how to comply with considerable new requirements and provide alot of additional information in future premarket submissions to the FDA. This is certainly good news, but I have lingering confusion because of the lack of mention in any of these new documents from the FDA of the adverse events involving these devices with which I'm familiar. An Appendix to the Guidance document lists the following categories of "Risks to Health" with infusion pumps: Overdose, Underdose, Delay in Therapy, Incorrect Therapy (wrong medication or correct medication but wrong dosage or infusion rate), Air Embolism, Trauma (burns, cuts, abrasions, bruising), Electric Shock, Infection, Allergic Response, and Exsanguanation. Perhaps the numerous cases of chondroylsis and tissue necrosis are intended to be included in one of these categories (Infection? Allergic Response?).
When I think again about the number of adverse events--56,000--reported involving all types of infusion pumps over just the last 5 years, I realize that the number involving local anesthetics, even if it's 500 or more, is likely to be less than 1% of the overall events. Where do local anesthetic infusion pumps and the injuries they appear to cause fit into the broader regulatory and safety scheme involving this class of devices? My initial reaction is that the problems with pain pumps don't have much to do with design, human factors, or manufacturing issues (and certainly not software). I will certainly reserve judgment and keep an eye on how the new oversight regime takes shape. Of course, it will also be interesting to see how these developments may affect litigation involving injuries and deaths from PCA and other programmable pumps. I can envision claims which were initially viewed as malpractice expanded to also (or instead) focus on the liability of the pump manufacturer.
