Identifying and Preventing Causes of Lab Errors

By ThinkReliability Staff

A man was mistakenly told he had HIV. A baby who died from a blood disorder that could have been treated during pregnancy, but wasn’t because the routine blood screen came back clear. A little girl who had to receive a second transplant after the test to verify her acceptance of a new organ was run incorrectly. These are just some of the cases mentioned in a watchdog report about how laboratory errors and weak oversight put patients at risk.

There are 7 to 10 billion medical laboratory tests run in the US every year. Lab tests influence about 70% of medical decisions. Having the wrong information from these tests can be deadly, and there is no good data about how many lab tests may be inaccurate, or may be negitively impacting patient safety. Laboratories are generally overseen by accrediting organizations but the results are almost always private, and there have been recent cases where federal regulators have had to step in because serious deficiencies in lab processes were identified.

The risk isn’t just for patients. An employee was infected with HIV and hepatitis C after a machine malfunctioned, splashing contaminated blood product onto her face. The employee had warned her boss previously that the machine was broken and cross-contaminating samples. Patients can also receive wrong information that isn’t harmful to their physical health but causes all sorts of other problems, such as incorrectly run paternity tests that improperly rule out a man as the father of a child.

The process involved in laboratory testing – from taking a specimen from a patient to delivering the results – is complex, and there are potential issues at each step that can lead to inaccurate results. These causes can be visually diagrammed in a Cause Map, or a visual cause-and-effect diagram. (To view the Cause Map, click “Download PDF” above.) In this case, potential causes of lab errors are captured and analyzed for potential solutions. These causes include labeling of samples, time and storage conditions of the samples, use of proper (and non-expired) products to treat the samples, and calibration of the machines used for the testing.

Actions that reduce the risk of inaccurate lab results should be in place at all labs, but even with a well-planned process, mistakes can happen. That makes the addition of checks and oversight into the process incredibly important. Says Michael Baird, the chief science officer and laboratory director at DNA Diagnostics Center, “I will agree that mistakes are something that can happen whatever you do. You just need to have the appropriate controls in place for when a mistake happens, (so) you can catch it before it goes out the door.”

For example, at the lab Baird runs, samples used for DNA checks are run independently by two different technicians and when a man is ruled out as the father of a child, there is a double-check in place. Other labs have incorporated alert systems for time-sensitive specimens and have hired technical directors responsible for overseeing the labs.

There are also steps patients themselves can take to minimize the impact on their safety from potential lab testing errors. First, ensure that any samples taken are labeled immediately and with accurate information. If you’re at all unsure about a test result, get a second opinion at a different lab. Complaints about a lab should be directed to state health officials.

To view the Cause Map addressing potential causes of laboratory errors, click “Download PDF”. To learn more, read the watchdog report.

Measles Vaccine Provides Multiple Protections

By ThinkReliability Staff

For previously unknown reasons, children who received the measles vaccine were less likely to die from infectious diseases other than measles.   According to Michael Mina, a postdoc in biology at Princeton University and a medical student at Emory University, the difference is significant.  “In some developing countries, where infectious diseases are very high, the reduction in mortality has been up to 80 percent.  So it’s really been a mystery – why do children stop dying at such high rates from all these different infections following introduction of the measles vaccine?”

Based on epidemiological data from countries before and after the measles vaccine was introduced, scientists believe they may have an explanation for this mystery that is part correlation and part causation.  So what’s the difference (and why do we care)?

Correlation means that two or more events tend to occur about the same time and might be associated with each other, but aren’t necessarily connected by a cause-and-effect relationship.  Causation means that a specific action causes a second event to happen.  A cause-and-effect relationship results from causation.   Sometimes it’s very difficult to distinguish between the two.  This is where the importance of evidence comes in.

In this case, part of the decrease in death due to infectious diseases can be considered due to correlation.  In this case, children who received the measles vaccine must have had access to healthcare, including the measles vaccine.  If they received the measles vaccine, they were also likely to receive other vaccines and treatment for other infectious diseases, meaning their death rates from other diseases were also lower.  The measles vaccine did not cause the reduction in deaths from infectious diseases, the access to healthcare did.  Getting the measles vaccine also resulted from the same cause, access to healthcare.

In addition to this correlation, epidemiological data from several countries from prior to the introduction of the measles vaccine shows that the number of measles cases predicted the number of deaths from other infectious diseases two to three years later.  Their hypothesis, supported by studies in monkeys, suggest that the measles virus actually erases immune protection to other diseases.  So, if a child gets measles, he or she loses some of the immune system’s “memory” of how to fight diseases can also be wiped out.  Preventing a child from getting the measles (by getting a measles vaccine) is believed to prevent deaths from other infectious diseases as well.

Although more testing is needed to verify the causation, scientists hope it will provide more evidence for parents to vaccinate their children.  Epidemiologist William Moss, who studies the vaccine at John Hopkins University, says “The reduction in overall child mortality that follows measles vaccination is much greater than previously believed.  I think this paper will provide additional evidence – if it’s needed – of the public health benefits of measles vaccine.  That’s an important message in the U.S. right now and in countries continuing to see measles outbreaks.”

To view the cause-and-effect relationships (both correlation and causation) between the measles vaccine and decreased mortality from childhood infectious diseases, please click on “Download PDF” above.  To learn more about the epidemiological study, click here.

Safely using a treadmill is not quite as simple as it seems

By Kim Smiley

Did you know that treadmills are the riskiest exercise machines?  I sure didn’t, but I have to admit that I have fallen off one before.  (Based on conversations with my coworkers, this isn’t all that uncommon.)  As recent headlines have made clear, using a treadmill safely may not be quite as simple as it seems.

According to data from the National Electronic Injury Surveillance System, about 19,000 people went to the emergency room (ER) because of treadmill injuries in 2009, which is about triple the number of injuries reported in 1991.  More and more people are using treadmills and the number of accidents has increased as well. Although only a small percentage of the injuries are serious, about 30 deaths related to treadmill use were reported between 2003 and 2011.

Understandably, the details surrounding Dave Goldberg’s death have not been released to the public, but it is believed that he slipped while using a treadmill and hit his head when he fell.  Falls off treadmills that result in serious injury are rare, but they have the potential to cause significant injury and even death. More common injuries associated with treadmill use are less serious overuse injuries, such as strains and sprains.

Children are at particular risk of being injured by treadmills.  A motor propels the belt on treadmills and children can get their extremities caught in the moving belt or suffer burns if they accidently turn a treadmill on or one is left running while unattended.  Of the 19,000 ER visits associated with treadmills in 2009, nearly a third were for children under age 9.

So how do you stay safe while using a treadmill?  The number one rule is to limit distractions.  Using a phone or watching TV puts you at a much higher risk of accidently misplacing a foot and falling.  (Trying to write an email while I walked on a treadmill is what resulted in my own fall.  Luckily, only my pride was injured, but I have learned my lesson.)

Treadmills have also risen in complexity and all the buttons and options can be distracting, especially if you are unfamiliar with the specific equipment.  Make sure you understand how to use the treadmill prior to starting the belt.  If you have balance issues or are elderly, you should also check with a doctor prior to using a treadmill.  And lastly, start by walking slowly and gradually increase the pace of the treadmill so that you aren’t caught unaware by how quickly the belt is moving.

To view a Cause Map of this issue, click on “Download PDF” above.

Confusion over Electronic Health Record Entry Leads to Death

By ThinkReliability Staff

A woman seen at an Illinois emergency room for a puncture wound from a gardening tool died of tetanus. Tetanus has a high fatality rate and there is no cure once it is developed, but the tetanus vaccine provides high levels of protection, even when given after a wound is sustained.   (Tetanus generally takes several days to incubate after a puncture wound that delivers the C. tetani spore, caused by an object that may have been exposed to feces, such as any object outdoors.)

Upon receipt of a threatening puncture wound, it is recommended that a patient be given a tetanus booster if it has been more than five years since an immunization has been given. It is unclear when the woman had last had a tetanus booster, but if status is unknown, giving a booster is also recommended. Despite coming to the emergency room for a puncture wound that was threatening with an unknown immunization status, the woman did not receive a tetanus shot. We can look into the details of the case in a Cause Map, or root cause analysis. This format diagrams the cause-and-effect relationships that led to an issue – in this case, the death of a patient from tetanus despite seeking treatment from a hospital.

In this case, the woman died of tetanus because she was infected with tetanus by being stabbed with a garden fork (for reasons which are unclear), and because she was not effectively immunized against tetanus. The patient was ineffectively immunized because she did not receive the recommended tetanus immunization.

During the patient’s intake by a nurse, the immunization status in the patient’s electronic health record (EHR) was selected as “unknown/ past 5 years”. The physician treating the woman did not request any clarification, but apparently considered that her shots were up-to-date and did not order a booster. This clearly indicates a poor design in the EHR as an “unknown” status would indicate the need for a booster, and having a shot within the “past 5 years” would not.

This confusion illustrates the issues being seen during the increased use of electronic health records. In their report Health IT and Patient Safety: Building Safer Systems for Better Care by the Institute of Medicine, they state, “designed and applied inappropriately, health IT can add an additional layer of complexity to the already complex delivery of health care, which can lead to unintended adverse consequences.” A review by a medical malpractice insurer showed that EHR issues were involved in only 1% of lawsuits concluded from 2007 to 2013 but that percentage had doubled from 2013 to early 2014, and more are expected with the increased adoption of EHRs. This is disappointing news for an incentive program for the use of EHRs, which hoped they would make hospitals safer. Data on whether or not that has occurred is mixed.

Because of their concerns, the Institute of Medicine has recommended the creation of an information technology (IT) safety center to investigate EHR risks. So far the proposal has not been funded by Congress. Others think that a government-supported fund to compensate victims, similar to that used for vaccine injuries, may be necessary.

The Office of the National Coordinator for Health Information Technology has released a guide on identifying and addressing unsafe conditions associated with health IT (available by clicking here). It calls for providers, EHR developers and policymakers to ensure health IT is used to improve patient care and protect patient safety.

To view the Cause Map of the tetanus death, please click on “Download PDF” above. To learn more about identifying and addressing unsafe conditions associated with health IT, click here.


Listeria in Ice Cream Causes 3 Deaths

By ThinkReliability Staff

On April 20, 2015, the Centers for Disease Control and Prevention (CDC) announced a recall of all Blue Bell Creameries products due to possible contamination by Listeria monocytogenes.  While the company has not yet determined the source of the outbreak, they are working with outside agencies to determine potential causes and implementing solutions to reduce the risk of food-borne illness in the future.  Says Paul Kruse, the CEO and president, “We’re committed to doing the 100 percent right thing, and the best way to do that is to take all of our products off the market until we can be confident that they are all safe.  At this point, we cannot say with certainty how Listeria was introduced to our facilities and so we have taken this unprecedented step.  We continue to work with our team of experts to eliminate this problem.”

Performing a root cause analysis can help clarify the goals of an investigation, determine the causes of the problem(s) related to an issue, and provide ideas for action items to reduce the risk of the issue recurring.  We can gather the information known so far about the outbreak in a Cause Map, or visual root cause analysis.

The Cause Mapping process begins by capturing the what, when and where of an incident.  Here, the “what” is the Listeria outbreak.  The “when” in this case is believed to have started in 2010 and continued to the present.  It can be helpful to capture any noted differences about the particular investigation.  For example, most outbreaks don’t last 5 years.  The use of genome sequencing (starting in 2013) allowed investigators to tie Listeria cases from 2010 on to this particular outbreak.  An additional difference is that Listeria can replicate in very cold temperatures.  This is unusual because freezing foods generally reduces the risk of propagating food-borne contamination.  The “where” is across the US – all products have been recalled and all plants have been shutdown, with several having been implicated in spreading Listeria.  Another useful piece of information can be the task being performed.  In this case, the contamination was discovered during random sampling.

The next step is identifying the impacts to the goals.  For this incident, the safety goal was impacted due to the sicknesses and deaths.  The outbreak of Listeria can be considered an impact to both the environmental and customer service goal, while the loss of production (no Blue Bell products are currently available or being produced for consumers) is an impact to the production goal.  The disposal of the estimated 8 million gallons of ice cream covered by the recall impacts the product goal, and the response and investigation impacts the labor goal.

The analysis step begins with an impacted goal.  Asking “why” questions develops the cause-and-effect relationships that led to the impacts.  In this case, the sicknesses and deaths were caused by a Listeria outbreak.  In order to have a food-borne illness outbreak, the food needs to be contaminated AND it needs to be delivered to consumers.  In this case, the contamination was not known because ice cream is not tested for Listeria.  There is no history of Listeria outbreaks in ice cream and testing is difficult on perishable products because of the time required.  Once ice cream products are again manufactured for consumers, Blue Bell has said it will implement a test and hold process (holding product until testing comes back negative).

The Listeria contamination results from the introduction of Listeria into the ice cream.  As discussed before, Listeria can replicate in cold temperatures.  The contamination source is likely surfaces in the production facilities or cross-contamination from other food products.  Because multiple plants are contaminated and cleanliness issues have been a concern in the past, it is likely that the outbreak is due to contamination of surfaces, on which Listeria can remain for a long time if not properly sanitized.

In addition to the test and hold process, Blue Bell is in the process of implementing a number of other changes to reduce the risk of future contamination.  Employees are being trained in microbiology and an expanded cleaning and sanitation program.  Prior to production resuming, equipment is being disassembled, cleaned, and tested for contamination and design changes that would make cleaning easier (reducing the risk of future contamination) are being considered.

While it is sometimes difficult to determine the success of solutions, the test and hold process to be used for future ice cream products should provide almost real-time feedback on the success of the programs and ensure that future problems are quickly identified.

To view a one-page PDF of the analysis and solutions, please click on “Download PDF” above.  To learn more about the ice cream Listeria outbreak, click here.  To read our previous blog about the 2011 fatal Listeria outbreak in cantaloupe, click here.