Did Cognitive Bias Result In Death Of Boston Hospital Patient ?

Surgical error at Tufts prompts widespread changes
By Liz Kowalczyk
Boston Globe
August 31, 2014

Caroline Carcerano arrived at Tufts Medical Center hoping that a brief procedure would relieve lingering symptoms from a back injury. In the operating room, the neurosurgeon requested a special dye to test the location of tubing that had been threaded into her spine. But the pharmacy didn’t have it and provided a different one.

The surgeon checked the label, hospital executives said, and then injected it, twice.

After Carcerano awoke with severe pain and seizures, caregivers zeroed in on the substitute dye, whose label clearly warned against use inside the spine, according to a report from regulators who investigated the error.

“A mistake was made,” the neurosurgeon, Dr. Steven Hwang, immediately told Carcerano’s two sons as they watched over their 74-year-old mother. “We gave her the wrong dye.’’

Carcerano died the following day last November, unleashing hospital and government inquiries that have led to widespread safety improvements in Tufts operating rooms this year and may highlight medical errors involving “cognitive bias” — an area of growing interest among researchers. The label on the dye read “not for intrathecal use,’’ meaning it should never be injected into the spine. But hospital executives said Hwang did not notice that warning, and instead saw what he anticipated the label would say — the name of a dye intended for injection into the spine.

Providers don’t always move quickly to offer compensation in cases such as patient Caroline Carcerano’s, despite a new law.

Thousands of patients are injured in hospitals across the country each year because of mistakes, and some of those occur when caregivers see what they expect to see on medication labels and in medical charts — and not what the labels and charts actually show.

The case also highlights how even when a patient is harmed by an indisputable medical error, providers and malpractice insurers don’t always move quickly to offer compensation — despite a new state law intended to encourage settlements in clear-cut cases before they reach court.

Last month, eight months after Carcerano died, attorneys hired by Tufts’s malpractice insurer mailed letters to her family denying that the surgeons, including Hwang, and pharmacists involved in her surgery were negligent in her death, or injured her.

Her sons, Michael and Stephen Carcerano, found the letters baffling. “A mistake was admitted, and now they’re saying it’s not their fault,’’ Stephen Carcerano said.

The brothers filed a lawsuit three weeks ago in Suffolk Superior Court against the hospital and 12 pharmacists, nurses, and surgeons. The insurer made a settlement offer soon after the Globe inquired about the case, said William Thompson of Lubin & Meyer in Boston, which is representing the family.

Hwang and Tufts executives said they could not comment on Caroline Carcerano’s case because of the pending lawsuit, but the hospital said it has a “long-standing policy and practice of positive and collaborative relationships with patients and families.’’

Following the error, and a second, unrelated misstep in January involving another patient, Medicare conducted a full-scale inquiry into hospital practices in February. In the second case, a resident removed an intravenous tube from a cancer patient without first elevating his feet, as hospital policy requires, causing an embolism and subsequent heart attack and severe brain damage.

Tufts adopted a series of hospitalwide improvements as a result of the two cases, including requiring surgeons and operating room nurses to submit detailed written medication orders to pharmacists. For the removal of intravenous lines, two staff members now use a checklist that includes the proper positioning of the patient. During a follow-up inspection in May, state investigators found no patient care problems at the hospital.

Carcerano came to Tufts last year after a difficult few months.

She fell in her Watertown apartment last summer and broke several vertebrae, her bones fragile due to osteoporosis. Massachusetts General Hospital surgeons fused together several of the bones to immobilize them and ease her pain, but in the following weeks, leg spasms impeded her progress, her sons said. A doctor recommended she have a pump stitched underneath her skin to get calming medication directly to her spine, and out to her muscles, faster — often a two-hour outpatient procedure.

According to the Medicare investigative report, Hwang asked a nurse for “Omnipaque,’’ a dye used in spine surgery. A pharmacist told the nurse that the operating room pharmacy did not carry Omnipaque and instead handed her two bottles of a different dye, MD-76. “This is what we have,’’ the nurse told Hwang.

When the surgery ended after more than four hours, Hwang told Carcerano’s sons that it did not go as well as he would have liked, but that the pump should work OK. Soon, a nurse reported that she was waking up “rough” and asked the brothers to come see her.

It took until the next day to figure out that Carcerano had received the wrong dye, and when Hwang acknowledged the error, Michael Carcerano asked how such a terrible mistake could happen. “He said he asked for one dye and they gave him another,’’ Michael Carcerano said. “I said, ‘You didn’t check it?’ He said, ‘The nurse gave it to me and I used it.’ ’’

Clearly, other missteps occurred before the substitute dye got to Hwang. No one else along the line took note of the dire warning on the MD-76 label.

By the time Hwang picked up the vial, he “saw what he expected to see and proceeded,’’ said Dr. Saul Weingart, chief medical officer, an error he called “confirmation bias,” a type of cognitive bias.

Dr. Patrick Croskerry, an emergency room doctor in Nova Scotia and a world-renowned specialist on cognitive errors, gave it another name: ascertainment bias. “The surgeon trusted the person who handed him the vial. You expect them to be correct. What you expect to happen will happen because most of the time it actually does.’’

Specific safeguards should be put in place so it is not “possible for the physician to make that error,’’ he said.

Tufts executives said they have tried to do just that. Therese Hudson-Jinks, vice president of patient care services, said most hospitals rely on verbal orders for medications not kept in the operating room: The surgeon asks for a specific drug from the nurse, who then requests it from the pharmacist. Nurses and surgeons are supposed to verify that they have received the correct medication.

In switching to more detailed written orders except in emergencies, Hudson-Jinks said the hospital has added more layers of protection for patients. Among the information the order must contain is how the medication will be administered, including whether it is intended for use in the spine. In this case, the pharmacist would know not to substitute a dye like MD-76.

In cases like Carcerano’s, where there has been an unquestionable medical error, a state law passed in 2012 created a six-month “cooling-off period” for settlement talks before a patient can sue.

The new law also allows providers to apologize for an error without having the admission used against them in court. The cooling-off period begins when the patient or family files a “notice of intent’’ to bring a claim, as the Carceranos did in February.

Bill Dailey, the hospital’s attorney, said cases take longer to resolve when multiple caregivers are involved, in part because lawyers must determine each individual’s role in the error — and what portion of any settlement their insurance policy is responsible for.

But some hospitals and insurers say patients and families should not bear the brunt of a delay.

Six Massachusetts hospitals have started a pilot program to offer patients harmed by medical errors a prompt apology and early financial settlements, and are evaluating whether the program increases patient satisfaction and safety and reduces costly lawsuits. So far, the group has examined 450 cases, of which 10 percent were determined to involve an avoidable injury that caused significant harm. About one-third of those have been settled so far, said Dr. Kenneth Sands, chief quality officer at Beth Israel Deaconess Medical Center, one of the participating hospitals.

Stephanie Sheps, director of claims for Coverys, a large medical malpractice insurer, said the company and others involved in the project are developing a policy to settle early and divvy up the blame later.

“You should be able to work out compensation even if there are multiple defendants if there is a clear-cut avoidable injury,’’ said Dr. Alan Woodward, one of the leaders of the effort. “It’s morally and ethically the right thing to do.’’