The Voice Told Me to Press the Medtronic-Physio Control LIFEPAK CR SHOCKbutton. Where's the Button?

Posted by Armand RossettiSeptember 16, 2008 12:33 PM

Physio-Control (Physio) is a wholly owned subsidiary of Medtronic Corporation that has distributed over 650,000 automated external defibrillators (AEDs), worldwide. Physio holds more than 70% of the domestic emergency services market, and 50% of the domestic in-hospital market. Notwithstanding that impressive market share, Physio has failed to ensure good manufacturing practices. But before we discuss manufacturing, let's take a look at how an AED works.

When people experience a sudden cardiac arrest, AEDs are designed to restore normal heart rhythm by delivering a metered electrical shock. There are two types of LifePak CRs; automated and semi-automated. While the automated model assesses the cardiac arrest and delivers the shock automatically, the semi-automated model delivers a voice message to the responder administering the treatment, instructing that person to push the “SHOCKbutton.” Probably to save assembly line costs, automated models are built exactly the same way as semi-automated models and they contain a SHOCKbutton that is covered with a membrane (because it is not needed).

Curiously one responder, who was in the middle of using the semi-automated version of the LifePak CR on a victim in need, heard the voice telling him to press the button, and couldn't find it anywhere. But the written instructions seemed pretty clear.

Here’s a copy of the LifePak CR Plus operating instructions that contain clearly written information and a picture of the button:

“SHOCK button:

The SHOCK button is only provided on the semiautomatic model. When pressed, this button delivers a shock to the victim. You cannot deliver a shock to a victim unless the defibrillator instructs you to do so.” [Page 2-7]

“The LIFEPAK CR Plus and LIFEPAK EXPRESS defibrillators are designed for indoor and outdoor use. Each has two models available—fully automatic and semiautomatic. After the electrode pads are applied, the fully automatic model evaluates the heart rhythm and, if a shockable rhythm is detected, delivers a shock without any responder assistance. The semiautomatic model evaluates the heart rhythm but requires the responder to press the shock button if a shockable rhythm is detected. Both models have voice instructions that guide the responder through the defibrillation process.” [Page 1-8]

“The semiautomatic defibrillator has a highly visible shock button that the responder must press when the defibrillator issues a shock voice instruction.” [Page 1-9]

A picture of the defibrillator with SHOCK button appears in the manual on Page 2-6. So, what could be the problem? Let's start with the recall notice.

On August 28, 2008, the FDA announced a Class 1 Recall of Physio’s LifePak CR Plus Automated External Defibrillators (AEDs). The notice contained an FDA statement providing a reason for the recall:

“The AED instructs the responder, by voice prompts, to press the shock button. However, the shock button is covered and is not visible. Therefore, the responder is not able to provide therapy (shock).”

In addition, the FDA’s notice does mention that the recalled units were manufactured between 2004 and 2007. The notice, however, is rather vague about the number of units recalled or the exact reason for that recall. Here is some additional information.

Physio equipped 249 of the automated models (having covered SHOCKbuttons) with the semi-automated model’s software, and that mistake turned the automated models into semi-automated ones with stealth SHOCKbuttons. There is some additional information that mmight shed some light on this quality control snafu.

In October 2006, the FDA concluded an inspection at Physio’s manufacturing plant that identified a host of violations, including poor procedures, failure to investigate medical device complaints, and failure to report issues to the FDA.

On April 28, 2008, 120 days to the day of the August 28^th recall Medtronic’s Physio-Control Unit reached a “deal” with the FDA over how to improve quality problems related to all of its external defibrillators, and this was one year after Physio was forced to halt US shipments of all defibrillators. Brian Webster, President of Physio-Control stated the following:

“During the last year, we’ve made significant investments and improvements to our quality systems and we are pleased to have a plan that formalizes the path to resume full distribution. We are working with the FDA to expedite resumption of full operations.”

However, according to documents that the agency filed in connection with the consent decree that Physio filed with the US District Court for the Western District of Washington, the quality issues that the FDA identified were still lingering in April 2008. Violations of the consent decree could carry financial penalties amounting to $20 million a year, with a $7 million cap if Medtronic should sell a controlling interest in Physio.

In light of all of the above, Medtronic’s recent problems with its Sprint Fidelis internal cardiac defibrillator leads come to mind, and a couple of questions arise. What are the implications of a lack of good manufacturing practices at Physio? Is that deficiency representative of the Medtronic management philosophy across the entire product spectrum?

There is no question that medical device competition is a real world dog eat dog environment. And Medtronic has had its hands full with hordes of patent lawsuits, recalls, inspections, etc. Perhaps Medtronic should first concentrate on the mundane but important aspects of its business, such as good manufacturing practices and medical device quality control.