A drug called digoxin provides a strong assist to a weakened heart. But a doctor has to keep track of so many risks when using it that the situation often can get out of hand.
It's only one of many such medical juggling acts affecting hundreds of sick people in the typical hospital. For clinicians who are tapping the potential of computers to reduce errors, though, digoxin is often their first target.
Consider this minefield of factors:
Digoxin slows and strengthens heart rhythm in a patient with congestive heart failure or heartbeat irregularities, but it's effective only in a narrow dose range. If it's too low, it's useless; if it's too high, it could be fatally toxic, says Terri Andrews, clinical systems manager at Alamance Regional Medical Center, Burlington, N.C.
In addition to the dose a physician calculates, a lot of things going on in an ailing body can affect that safe and therapeutic range.
A doctor could appropriately weigh all those factors when putting a patient on digoxin. But within days or even hours, one or more readings on those interrelated factors could change-and the right dose could become wrong.
The ability to right wrongs before they can do damage is the most dramatic feature of clinical information systems now beginning to show their stuff after years of delivering too little at too much cost, industry observers say.
A feature called decision support takes in vital signs, lab tests, medication rosters and other distinct data on a patient. At a speed no human mind could match, a computer program analyzes the information against predefined formulas and picks up danger signals that call for action by a physician or nurse.
The computer doesn't replace physician decisionmaking but rather mimics how a doctor would think through the patient's medical situation when presented with the same information, experts say.
The big differences are twofold:
* The computer electronically retrieves all the latest lab values, medication interaction data, previous test results and pertinent protocol details that the doctor should take into account to make a quick but well-informed decision.
* The computer doesn't forget when it's in a hurry.
Much of the information that would point to an imminent adverse event is available somewhere to a physician. But without the aid of a computer it's often not possible to compile all the factors in a medical decision and bring it to the appropriate authority in a timely way every time for every patient, says Robert Raschke, M.D., a critical-care physician on staff at Good Samaritan Regional Medical Center in Phoenix.
The medical facility was early to embrace a computerized analysis and alert system, which can detect dozens of potentially dangerous situations before they can cause irreversible harm to a patient.
In a study of alerts at Good Samaritan involving 37 adverse drug events, the computer system detected potential problems more than 1,000 times among 9,000 patients during a six-month period in 1997. More than half the alerts were well-founded.
The problem picked up the most was potential digoxin toxicity. But in all but 14% of the cases, a doctor recognized the problem by the time a pharmacist contacted him with the news.
A second leading cause of alerts, however, went unrecognized by nearly all ordering physicians. A dye administered to increase the contrast of diagnostic images can cause kidney damage in people with diabetes or problems with kidney function. An alert occurred 375 times, and nearly half the time the computer was correct. But the danger went "clinically unrecognized" 97% of the time, according to the study published in an October 1998 issue of the Journal of the American Medical Association.
Those results argue for a safety net to standardize how physicians react to a potential patient danger, Raschke says. "If it's right to do something about this, we should always do something about this instead of doing it haphazardly," he says.
Where computers fit in
In the quest to make healthcare facilities safer for their patients, executives shouldn't make computers the be-all and end-all of a patient safety solution, experts say. "I would never touch the technology until I have put in place significant standardization and significant cultural change," says Roger Resar, M.D., director of the patient-safety program at Luther Midelfort-Mayo Health System, a healthcare network in Eau Claire, Wis.
But the inherent ability of computers to crunch numbers and manage complicated scenarios makes information technology valuable in tracking and controlling scores of separate medical situations occurring simultaneously.
"You get to the point where you do need IT to take you to the next level," says Cynthia Spurr, corporate director of clinical systems management at Partners HealthCare System, Boston, which has deployed alerts at the point of electronic ordering at its Brigham and Women's Hospital since the early 1990s.
Among those agreeing with that observation are the Institute of Medicine's committee on healthcare quality and the Leapfrog Group, a coalition of large U.S. corporations trying to use its healthcare-purchasing leverage to accelerate quality-related change in hospitals.
"Central to many IT applications is the automation of patient-specific information," according to the IOM's report on transforming the healthcare system, Crossing the Quality Chasm. The report, published in March, says the "use of medication order entry systems using data on patient diagnoses, current medications, and history of drug interactions or allergies can result in sizable reductions in prescribing errors."
The Leapfrog Group went further, saying it would campaign specifically for computerized order entry systems meant for use by physicians and linked to software that prevents prescribing errors. To meet a standard of comparison for rewarding quality, hospitals not only would have to use such a system but also demonstrate that it intercepts at least 50% of common serious prescribing errors.
A fact sheet on the standard calls computerized physician order entry "remarkably effective" because it can "intercept errors when they most commonly occur-at the time medications are ordered."
But a lot of what these prescribing-error prevention systems are supposed to accomplish can be achieved without physician order entry, Raschke says. Putting physicians at the alert point has its benefits, but it also introduces a host of costs and complications that should not be forced on healthcare organizations before they're ready and able, he says (See related article, p. 24).
Within a hospital's grasp
Good Samaritan works behind the scenes catching medication conflicts instead of using a physician ordering system. Alerts fire at the computer of a pharmacist, who screens them for validity and contacts the appropriate physician or healthcare professional.
Raschke says the facility has "a good system, but the technology is not beyond other hospitals." With an older laboratory information system and other departmental applications that capture patient data, the medical center can pull together the basic computerized information it needs to apply program logic from a decision-support application developed by Cerner Corp., a Kansas City, Mo.-based information systems and services company.
"Everything we're doing at Good Samaritan is doable at other hospitals," Raschke says.
In fact, the potential can be daunting, he adds. "The number of different drug events is huge," he says. "We decided to start chipping away at it-start with the easy ones and keep going."
Much of the information needed to track and warn of adverse events can be assembled from lab-test values continually being recorded on patients in a laboratory information system, Raschke says.
Those test results are being plumbed in efforts to get a handle on digoxin toxicity. If a patient's potassium level is too low, it could allow digoxin to reach toxic levels in the blood-and that could lead to the type of life-threatening heartbeat irregularity the drug is supposed to prevent, says Dorrie Napoleone, director of clinical information systems at Montefiore Medical Center in New York.
The medical center is implementing an alert in conjunction with an order for digoxin that warns a doctor if a patient's recent test for potassium level was too low. The computer immediately presents an easy way to order a potassium chloride supplement. If the test was done too long ago, the computer asks the physician if he wants to order a potassium test, Napoleone says.
But if a patient's kidneys aren't functioning well, digoxin should be given at a low dose or not at all, says Andrews of Alamance Regional Medical Center, which also has geared up to scrutinize digoxin therapy. A lab test can monitor how much of a substance called creatinine is being cleared from the patient's kidneys, and that tells clinicians how well or poorly the patient's kidneys are working, she says.
Montefiore studied the impact of its alert by monitoring the times it detected a digoxin order with a low potassium level. The alerts and prompts were not activated at the point of order but fired behind the scenes for research purposes. In the first two months of this year, the alert went off 103 times.
In 69 cases, doctors recognized on their own or from a colleague that a potassium supplement should be ordered, Napoleone says. But the situation wasn't recognized 34 times, which was enough justification to implement the digoxin alert starting March 15. "That's something everybody agrees should not be happening," she says.
On the flip side, too much potassium can cause cardiac arrest, Raschke says. An alert for excessive levels of potassium was among those developed for Good Samaritan's study of adverse events.
Another alert involved a new drug that combats high blood-sugar levels in diabetic patients but has a rare but threatening side effect called lactic acidosis. The drug, called metformin, was so new to the American healthcare market at the time of the study that doctors had no experience in watching out for the side effect, which is not easy to recognize, Raschke says.
The complications of these conditions are so serious that even alerts sometimes cannot intervene in time. The JAMA study reported that one patient on metformin was admitted to the hospital with symptoms that puzzled clinicians until an alert flagged the patient for possible lactic acidosis. The patient received treatment for the metformin complication but died a day later. Another patient identified with kidney problems and high potassium levels died an hour later of cardiac arrest.
Optimum uses for alerts
Physicians know about myriad effects of a patient's condition on the peak level of drugs in the body, but they might not be able to pause and calculate all the equations involved, says Brent James, M.D., vice president of medical research at Intermountain Health Care, Salt Lake City.
One example is an equation for estimating kidney function by measuring creatinine clearance rates, which figures into estimating peak drug levels. "I learned that equation in medical school. As a surgeon I never used it-in fact, the only people I ever talked to who routinely use that equation are pharmacists," James says.
"Even most internists and family practitioners find it too time-consuming, too difficult to do those routine calculations," he says. "It is fairly complex. But that's an ideal task for a computer."
At the other extreme, healthcare institutions run the risk of getting carried away with the technology, Raschke says. "You could definitely write too many alerts and drive docs nuts-to where they begin to hate these alerts." By working with physicians to agree on thresholds for drug levels, alerts can be developed so they don't burden doctors with false alerts, he says.
Besides pinpointing the problems to flag, a healthcare facility has to develop an adequate response to alerts, something clinicians at Good Samaritan learned from experience. "We were wrapped up in the technology of it, and we implemented our alerts before we had a good system of reacting to the alerts," Raschke says.
They were left with the knowledge that adverse events were occurring but not the processes to do something about them. "It was chilling," he says.
Once physicians understand that decision support systems can stave off the serious effects of adverse drug events on the well-being of their patients, the next problem can be the frustration of not being able to move fast enough to cover all the possible situations, Raschke says.
But there's enough benefit in each alert to "start somewhere and start chipping at it," he says. "Don't worry about the ones you're missing. Worry about the five things you're getting right now."