Barbara Scott relied on dialysis to do what her damaged kidneys could not. Three times a week, a machine pumped her blood out of her body, pushed it through a specialized filter, then returned it cleansed of waste. The bright crimson circuit kept the 73-year-old retired bookkeeper alive.

Until it nearly killed her.

Partway through Scott's treatment on Dec. 28, 2005, the tube feeding blood back into her became dislodged. A temporary employee at her storefront clinic in Poughkeepsie, N.Y., hadn't taped the tube in place properly, and the facility didn't follow safety rules requiring the connection to remain visible, regulators later determined.

As Scott rested under a blanket, more than a quarter of her blood pooled beneath her and spilled onto the floor instead of flowing back into her system. She barely managed to call for help before losing consciousness.

Dialysis patients die or are hospitalized every year as a result of catastrophic hemorrhages during treatment, a ProPublica review of regulatory and court records has found. In dozens of cases in which patients suffered such harm, government inspection records show, regulators later cited clinics for failing to adhere to minimum standards of care.

These incidents are among the most gruesome -- and most preventable -- lapses in a dialysis system that has some of the highest mortality and hospitalization rates in the industrialized world. Each year, about 1 in 5 patients die, almost twice the mortality rate of countries with the best outcomes.

No one knows for sure how often line separations or dislodgements occur during dialysis. They are relatively rare, but 5 percent of patients who responded to a 2007 safety survey by the Renal Physicians Association said they had a needle dislodge mid-treatment within the previous three months. Another review, based on incidents in a Pittsburgh hospital system, suggested that each year hundreds of patients may fall victim to more serious bleeding episodes.

The absence of more precise data points to a broader problem, patient safety advocates say. Though the government pays for most dialysis through Medicare, federal regulations do not compel clinics to report treatment-related errors, injuries or deaths, whether from bleeds or other mishaps. That's despite an overhaul of dialysis regulations in 2008, which, among other things, mandated that clinics have programs to improve patient safety.

"People don't want it out there -- it's liability, it's exposure -- but we have to have transparency to learn from one another's mistakes," said Tricia West, a nurse and former dialysis clinic owner who also served as president of the California Association for Healthcare Quality. "Things can and do happen, but it shouldn't be the same things over and over."

Officials at the Centers for Medicare and Medicaid Services said the agency's new administrator, Dr. Donald Berwick, a longtime patient-safety advocate, may bring a more aggressive approach to this issue.

"We are being challenged to do everything we can ... to address patient safety and to reduce errors in [all] settings of care," said Dr. Barry Straube, CMS' chief medical officer. "The dialysis world is an area in which we'd like to see that happen more."

Barbara Scott never really recovered. She was rushed to the hospital in shock and stayed for more than three weeks. Just 5 feet tall and always petite, she dropped below 100 pounds. Her face grew gaunt, her skin papery. When she finally went home, she was so frail she couldn't walk her dog or work in her garden.

"She'd sit and cry for no reason," said her daughter, Cathleen Sharkey.

Scott died soon after of heart failure. On the final day of her life, she hired an attorney to sue her clinic, Dutchess Dialysis Center, for negligence.

A spokeswoman for Fresenius Medical Care North America, which owns Dutchess Dialysis through an affiliate, said the company could not comment on the matter because of patient privacy rules. The company agreed to a $300,000 settlement in 2008, Sharkey said.

"This didn't have to happen," Sharkey said. "My mother was a woman to be reckoned with. She was dealing with dialysis the way she dealt with everything. She was organized, she kept track of her test results, she ate and drank exactly what they told her. She would still be here today."

Discovered Too Late, a Deadly Drip

Close to 400,000 Americans receive chronic dialysis, a number that has almost tripled in the last 20 years as obesity and diabetes have reached epidemic proportions. More than 90 percent of them receive what's called in-center hemodialysis, thrice-weekly treatments at outpatient facilities.

In a typical treatment, a technician attaches the patient to the machine by inserting two needles into the patient's access point. Each needle is attached to tubing. One tube carries the patient's blood into a filter called a dialyzer. Dialysate solution flows in the opposite direction, removing toxins and restoring the blood's chemical balance. The other tube returns the clean blood. Sessions average three to four hours in length.

Advances in technology have made dialysis simpler and safer, but it's hardly foolproof.

A patient in Petaluma, Calif., died soon after an incident in which a contract nurse -- given just one day of orientation -- reversed her bloodlines without using a clip to hold the tubes in place, and one became disconnected, inspection records show. At a clinic in San Diego, a staffer mistakenly connected a bloodline to a machine drain and not the needle returning blood to her body, regulators found. The patient, a 61-year-old woman, lost about a pint of blood and had to be hospitalized for a transfusion.

In their current generation, dialysis machines cycle patients' blood at a rate of 300 milliliters to 500 milliliters per minute, making dislodgements more dangerous than in earlier eras when treatments were done more slowly.

"It’s like turning up the pressure on your garden hose," said Jane Hurst, a registered nurse who consults on dialysis-related medical malpractice lawsuits for both plaintiffs and defendants. "The time it takes to lose a significant amount of blood is less" – in some cases, fewer than 10 minutes.

Seemingly routine treatments can suddenly become anything but. Larry Grammer's vital signs were stable a half-hour into his May 1, 2008, dialysis treatment at a clinic in Jacksonville, Ill. When his machine's alarm sounded 21 minutes later, however, the 68-year-old retiree was already unresponsive and gasping for air, a government complaint investigation shows.

Workers discovered that the tubing to the catheter in his chest had disconnected. "A large pool of blood" was found under his chair, the report said. Grammer was pronounced dead less than two hours after the incident began. The clinic's operator, DaVita Inc., declined to comment on the case, citing patient privacy rules. The company reached a confidential settlement with Grammer's widow.

Government regulations require clinic workers to keep patients in view continuously during treatments, and facilities can be cited for not keeping access points for bloodlines and needles visible at all times. On this, staffers can face resistance from patients themselves, who, despite the risks, often prefer to cover up for warmth or privacy.

Though dialysis machines are designed to sound an alarm or stop the flow of blood if they detect a significant drop in pressure, they can miss smaller fluctuations. Staffers, beleaguered by false alarms, sometimes change settings to be less sensitive or reset machines after an alarm without checking patients' lines.

ProPublica examined inspection records for more than 1,500 clinics in California, New York, North Carolina, Ohio, Pennsylvania and Texas from 2002 to 2009. We found at least one fatality resulting from needle dislodgements in each state during this period, plus dozens of additional cases in which patients required hospitalization, blood transfusions or other emergency interventions.

In several instances in which patients suffered fatal or near-fatal hemorrhages, inspectors concluded that clinics had too few staffers on duty to properly monitor patients. "I see it in almost every case I work on," Hurst said. She also often finds staffers have been working 12 or even 16 hours at a stretch. "That's when mishaps occur."

Employees at a Cleveland clinic in 2001 didn't notice Kathryn Stevens' line had become disconnected until she fell from her chair, unconscious from loss of blood, according to published accounts of a lawsuit filed by Stevens' survivors. Left with irreversible brain damage, Stevens lived another five months, unable to speak or eat on her own, before dying of an infection.

"She was a vegetable," said Ivory Stevens, her son. "Seeing her like that was two heartbreaks at one time. I almost wished they hadn't kept her alive." In 2002, the Stevens family obtained a $4.75 million settlement from her dialysis and nursing facilities.

Help also came too late for Shelton Crosland, whose bloodline disconnected during a September 2007 treatment at a dialysis center in Queens, N.Y.

According to an investigation conducted by state inspectors the following month, the technician tending to the 47-year-old construction site manager was also monitoring two other patients, collecting data from their dialysis machines, and ending the treatment of a third patient. A nurse was unavailable to help him because she was covering for a colleague on a break.

By the time clinic workers discovered Crosland’s line separation, the attending nurse said she did not use the center’s defribrillator to try to revive him because there was “so much blood that she was afraid for the safety of the staff,” the investigation report said. Crosland was dead on arrival at the emergency room.

Regulators cited his facility for not ensuring it had an adequate number of trained staff members on duty to provide safe care. Fresenius Medical Care, which operates Crosland's clinic, declined to comment on the case, again citing federal privacy laws. Crosland's widow has filed a lawsuit against the clinic; the case is ongoing.

Few States Require Reporting

Preventable lapses in care have received heightened attention since the Institute of Medicine's landmark 1999 report, "To Err is Human," which said as many as 98,000 patients died each year in U.S. hospitals as a result of medical errors.

More than 25 states now require certain facilities – most often, hospitals, ambulatory surgical centers and birthing centers – to report some types of adverse events. Several states use the 28 “never” events (as in, they should never happen) identified by the National Quality Forum, a nonprofit that sets standards for health care.

So far, these changes have mostly bypassed dialysis. Only a handful of states, including Colorado, Georgia, New York and Tennessee, mandate that dialysis units report incidents resulting in unexpected patient deaths or injuries.

Under Medicare regulations, clinics are obliged to record such incidents internally and to analyze them for purposes of quality improvement. Many do so, but some do not: ProPublica's six-state inspection review turned up more than 100 instances in which clinics were cited for not documenting or investigating errors and adverse events.

Nurses and other clinic staffers acknowledged that bleeding incidents sometimes aren't reported, particularly if patients do not need to be transferred to a hospital.

Natasha Smith, a technician in Colorado Springs, said her current facility records such incidents properly. That wasn't so at another center where she worked for three years. "Techs didn't want to do them. It's saying they did something wrong," she said. "There were all kinds of problems that were never reported."

Unpublished government cause-of-death data confirms that treatment-related bleeds kill patients each year: From 2006 to 2008, facilities gave "hemorrhage from dialysis circuit" as the primary cause of death for 18 patients and as a secondary cause for six more.

For many patients, however, cause of death is uncertain. Of almost 240,000 deaths reported to Medicare during this period, almost 1 in 5 were attributed to "unknown" or "other" causes, with no further information provided. Almost 700 deaths were attributed primarily to "hemorrhages from vascular access," or, more rarely, "accidents related to treatment." In a handful of cases, facilities checked off one of these, as well as "hemorrhage from dialysis circuit," as causes for the same deaths.

Ultimately, the true toll of such incidents remains unknown.

"This is the sort of thing no one keeps statistics on. It's bothered me for years," said Dr. Stephen Sandroni, now a professor at Texas Tech University's Paul L. Foster School of Medicine in El Paso. "The government pays for dialysis, and it's very expensive. Yet the government hasn't pursued data collection in this area. If this is a preventable cause of death, why isn't someone researching it?"

Frustrated by the lack of systemwide data, Sandroni reviewed the frequency of catastrophic hemorrhages in the dialysis units he supervised when he was director of nephrology and hypertension at Allegheny General Hospital in Pittsburgh, which had about 300 patients. He found that they occurred at a rate of 1 per 126,718 treatments and that 1 in 3 was fatal.

Based on his research, Sandroni co-authored an abstract for the November 2008 Journal of the American Society of Nephrology suggesting that -- even assuming a far lower fatality rate -- needle dislodgements might be killing more than 40 patients a year and injuring more than 400. To his disappointment, the work drew little interest from regulators or other dialysis providers.

"People want the good news," he said. "These are pretty tragic deaths. Someone may have years in front of them and suddenly, boom, they're gone. If you have even a couple a year, they're preventable, and in fact, you may be having scores a year."

Preventive Steps at VA Clinics

When the Renal Physicians Association conducted its safety survey, members discussed trying to establish an independent registry where dialysis providers could report adverse events such as treatment-related hemorrhages, but they concluded it would face too many hurdles, said Dr. Alan Kliger, the group's former president.

The association launched a website, Keeping Kidney Patients Safe, that offers ideas for improving patient safety and urges doctors and providers to share best practices.

There is one segment of the health care system that has embraced reporting accidents and errors as a way to guide improvement: the U.S. Department of Veterans Affairs.

All VA facilities, including its 66 dialysis units, are required to report not only events in which patients suffer harm, but also near misses. Reports are entered into a central, searchable database and are coded according to severity.

In October 2008, the VA's National Center for Patient Safety published an advisory (PDF) based on reports of bleeding episodes during dialysis. VA units logged 40 incidents considered "serious" between March 2002 and April 2008, or about 1 for every 62,500 treatments given in this period.

The VA’s study encompassed events less grave than those considered by Sandroni. Fewer than one-third of the incidents resulted in extended hospitalizations or deaths, in part because researchers considered episodes in which patients lost as little as 100 cubic centimeters of blood, about enough to fill an espresso cup. But by looking systematically at these cases, patterns emerged. Certain types of patients were clearly at higher risk, including those receiving treatment in isolation areas and those with dementia.

Based on these findings, the VA issued two safety alerts earlier this year aimed at reducing or preventing hemorrhages during dialysis treatments. It has ordered units to buy clips (PDF) that snap onto bloodlines and prevent them from loosening.

Starting this month, VA units also will use Redsense alarms, electronic blood-loss sensors, on patients getting dialysis in areas outside of chronic dialysis units or beyond staffers' sight lines; in addition, they may use the device on patients identified as at high-risk for needle dislodgements. The VA also has augmented training for staffers, putting new emphasis on keeping access sites visible.

Dr. Jim Bagian, a former astronaut, led the VA patient safety center from its founding in 1999 until last month, when he took an executive position with the University of Michigan Hospital System. He said there were two keys to launching the reporting program: First, persuading medical staffers to share information about adverse events without fear of reprisal or legal exposure; and second, showing them that their information could make a difference.

"You have to be willing to admit you're not doing as well as you could," Bagian said. "Most people don't have the guts to say that."

Researcher Lisa Schwartz contributed to this report.