What we do and don’t know about the shortage of blood culture bottles

In July, federal health officials warned hospitals that there would be a critical shortage of blood culture bottles that will stretch into September.

Blood culture bottles are key in diagnosing sepsis, a deadly infection of the bloodstream caused by a number of different bacteria. According to the Centers for Disease Control and Prevention, about half of U.S. labs get their bottles from a company known as BD, the supplier that is in shortage, meaning that the shortage could have big implications for patient care. Every hour that antibiotics are delayed in treating sepsis results in a 7.6% decrease in patient survival.

But what are blood culture bottles, and what do we know about the shortage?

What are blood culture bottles used for?

If doctors are worried about sepsis, they order a blood culture to detect the infection. That involves taking a 10-milliliter sample of blood — about the volume of a ketchup packet — adding it to a blood culture bottle full of nutritious broth that bacteria love.

That bottle goes into an instrument that incubates the blood mixture at a warm temperature and encourages any bacteria present to grow until they make the bottle cloudy, which triggers an alert notifying a lab technician that the patient is potentially positive for sepsis.

That sample, now full of bacteria, can go through a variety of stains, plate cultures, and PCR tests to determine exactly which bacterial strains are causing the infection and what antibiotics will be best for the patient.

The process of doing blood cultures used to be manual, but hospitals now run far more of them, and for sicker and more complex patients, said Romney Humphries, medical director of the microbiology laboratory at Vanderbilt University Medical Center. If health systems switched back to manual cultures, technicians would have to check hundreds of samples for cloudiness by eye, and could only do that about once every 12 hours. Humphries described the prospect of returning to manual cultures as “horrifying.”

After Humphries mentioned the manual process on a CDC call about the shortage, “I had at least 20 different people email me to ask for the protocol for how to do that because they’re worried they’re going to get to that point,” she told STAT.

How long has this shortage been going on?

BD told hospitals in late June that there would be a shortage and to expect to get fewer bottles.

Health systems said that BD originally framed the issue as temporary and not one that should cause alarm. But the first week of July, many saw shipments nosedive.

“They told us to expect about a 50% decrease,” said Sarah Orstadius, a laboratory operations manager at Northeast Georgia Health System, a five-hospital health system. “What we experienced was closer to about a 70% decrease.”

“It didn’t matter how many orders we placed, we simply weren’t getting anything. And when we were getting it, it was maybe like five bottles or 10 bottles, not even a full case,” said Humphries.

BD later determined that the shortage was worse than originally thought and now says it will go through at least September. When STAT asked for clarification, a BD spokesperson reiterated in a statement that the “issues are more complex than the supplier originally communicated” without elaborating.

Even though Humphries was able to work with BD to eventually get direct shipments of 900 bottles a week, Vanderbilt goes through about 6,000 bottles a month, she said, and it’s still not enough.

Can people switch suppliers?

Switching suppliers is complicated. Part of the problem is that the instruments that analyze the bottles only accommodate bottles of a certain size and shape, so labs can’t just switch to another brand of bottle as they would for more generic supplies like pipette tips or Petri dishes.

There are only three companies that make these analyzer instruments for U.S. labs. Apart from a few labs that use Thermo Fisher, the rest of the industry is split between BD and bioMérieux, a French company.

Switching from BD to another vendor would require several hundred thousand dollars to purchase new capital equipment and a few weeks — if not months — to install and validate the new system. Humphries said that Vanderbilt did decide to switch vendors, but that bioMérieux is no longer accepting new customers given the supply crunch.

Though bioMérieux doesn’t foresee its supply of blood culture bottles being affected, “We will not opportunistically pursue new business without first meeting the needs of our existing customers,” a company spokesperson told STAT via email.

Is patient care being affected right now?

Largely not, so far.

The CDC and the Food and Drug Administration have focused on encouraging stewardship: using best practices and conserving bottles. That includes reminding clinicians of which patients require blood cultures and which do not — to cut down on “just in case” orders. Some systems are instituting new rules in their electronic health records to help enforce stricter guidelines, hospital officials told STAT. Hospitals are also reconsidering their policies on how many samples they collect and whether they will do follow-up cultures, especially if the first one was negative.

Health systems representatives who spoke with STAT admitted that blood cultures are probably over-used, and that simply reining in orders has helped curb blood culture bottle usage while keeping clinicians from having to make tough patient care choices. However, as the measures hospitals have instituted have become stricter, taking fewer cultures means there’s an increased chance of missing infections.

The worst-case scenario still haunts clinicians: Without blood cultures to determine the right course of action, they could be prescribing the wrong antibiotics for patients. Physicians could be delayed in figuring out that a patient needs a stronger or different antibiotic, resulting in worse outcomes and even death.

Why is there a shortage?

There is an issue with the company supplying BD’s plastic bottles, though when STAT asked for clarification, BD refused to specify whether it was a raw materials issue or a manufacturing issue. The name of the supplier is also unclear. BD is “working directly with our raw material supplier of molded bottles to improve production line efficiency and output,” it said in a statement.

BD sources its bottles from a single supplier in Indiana and told STAT that it’s looked into getting a second supplier, but that the design of the bottle’s neck and the associated intellectual property have been “barriers to onboarding a secondary supplier.”

On a call with the CDC on July 15, BD’s microbiology vice president, Chris Beddard, said that this shortage is unique to these bottles and wouldn’t affect any other BD products.

When will the shortage end?

BD told STAT that it is bringing a German supplier of glass bottles online and expects to “realize improvements in the September 2024 supply,” though hospital officials who spoke with STAT said BD hadn’t specified whether these supply improvements would occur in early or late September.

On a call hosted by the CDC and the Infectious Diseases Society of America on July 23, Beddard said that the use of glass vials would be temporary until the plastic vial supply recovers.

What questions do doctors have for regulators?

On the July 23 call, clinicians peppered officials from the FDA and other regulatory bodies with questions about measures they could take: whether it was OK to use about-to-expire or expired culture media, whether labs would have to validate procedures for the new glass bottles, and when it was OK to skip follow-up cultures.

The FDA referred many of those questions to the Centers for Medicare and Medicaid Services, which operates the certification program for federally regulated labs. A CMS spokesperson told STAT that expired media can only be used if the manufacturer extends the expiration dates — which the FDA official on the July 23 call said the agency was considering — and that labs that have used glass bottles in the past can use those validation studies when the new glass bottles are introduced.

As part of a list of quality measurements that dictates how hospitals get paid, Medicare rates hospitals on the quality of their sepsis management, which includes blood cultures. Right now, clinicians told STAT they aren’t worried about not meeting Medicare’s quality requirements, but there would be a problem if they fully ran out of bottles.

A CMS spokesperson told STAT in an email that the agency isn’t tracking any issues with sepsis measures right now, but acknowledged issues could arise from the shortage. “We will continue to monitor the situation and issue guidance accordingly if issues are identified,” the spokesperson said.

Sally Weiss, vice president of workforce policy and strategic initiatives at the Maine Hospital Association, is worried about the lack of information about what hospitals should do if they do end up running out of blood culture bottles. Given current guidance, “it just doesn’t feel like there’s an acknowledgment that that actually could happen,” she said.

STAT asked the CDC what guidance is available for hospitals that may be running out of bottles. “This is a rapidly evolving situation and product availability varies greatly across settings with local nuances,” a CDC spokesperson told STAT in an email. The spokesperson pointed back to resources described in the previous CDC call and announcements and said that the agency is still trying to understand the impact of the shortage on health care delivery.

How do we fix this?

The BD shortage stems from the company relying on a single supplier for its plastic bottles. The immediate solution is to diversify sourcing, as bioMérieux has, perhaps stemming from a similar shortage of bioMérieux blood culture bottles in 2014. BioMérieux told STAT in a statement that it has multiple sources for its raw materials, bottles, and manufacturing, and has secured its supply of plastic bottles with its suppliers.

More broadly, the proprietary nature of the analyzers means they’re designed to fit only one kind of bottle made by one manufacturer. Lab managers and hospital executives floated the idea of either standardizing instruments to accept common bottles, or letting others manufacture generic versions of proprietary bottles. Companies should be allowed to make money off their intellectual property, said Steve Diaz, chief medical officer at MaineGeneral Health, “but shouldn’t there be some backup in case this happens?”

The American Hospital Association’s Nancy Foster, vice president of quality and safety policy, said that though not cheap, “fattening” the supply chain at all points — where the manufacturer, distributor, and hospital all hold on to a slightly bigger supply than needed — would also provide flexibility in times of crisis.

The incessant parade of supply chain problems, especially since the pandemic, has prompted many conversations, said Linoj Samuel, the clinical microbiology division head at Henry Ford Health System in Detroit. But no one has actually made any movement on solving the problem.

“What we need is a commitment from the government, from industry, from others to really move forward and build on some of these solutions and ideas and see what we can do,” he said. “It is a difficult, challenging problem. But if there was an easy solution, we probably would have done it. There isn’t one.”