Sunday, December 09, 2007

Preventing error

Atul Gawande had an interesting piece in last week's New Yorker on the power of the checklist to transform hospital outcomes. He likens modern critical care to the Boeing Model 299 test plane, which crashed on an important early outing due to a complexity-induced pilot error, but would later become, by virtue of a pilot's checklist, an important asset to the US Army in WWII as the B-17 bomber:
Medicine today has entered its B-17 phase. Substantial parts of what hospitals do—most notably, intensive care—are now too complex for clinicians to carry them out reliably from memory alone. I.C.U. life support has become too much medicine for one person to fly.

Yet it’s far from obvious that something as simple as a checklist could be of much help in medical care. Sick people are phenomenally more various than airplanes. A study of forty-one thousand trauma patients—just trauma patients—found that they had 1,224 different injury-related diagnoses in 32,261 unique combinations for teams to attend to. That’s like having 32,261 kinds of airplane to land. Mapping out the proper steps for each is not possible, and physicians have been skeptical that a piece of paper with a bunch of little boxes would improve matters much.

In 2001, though, a critical-care specialist at Johns Hopkins Hospital named Peter Pronovost decided to give it a try. He didn’t attempt to make the checklist cover everything; he designed it to tackle just one problem, the one that nearly killed Anthony DeFilippo: line infections. On a sheet of plain paper, he plotted out the steps to take in order to avoid infections when putting a line in. Doctors are supposed to (1) wash their hands with soap, (2) clean the patient’s skin with chlorhexidine antiseptic, (3) put sterile drapes over the entire patient, (4) wear a sterile mask, hat, gown, and gloves, and (5) put a sterile dressing over the catheter site once the line is in. Check, check, check, check, check. These steps are no-brainers; they have been known and taught for years. So it seemed silly to make a checklist just for them. Still, Pronovost asked the nurses in his I.C.U. to observe the doctors for a month as they put lines into patients, and record how often they completed each step. In more than a third of patients, they skipped at least one.

The next month, he and his team persuaded the hospital administration to authorize nurses to stop doctors if they saw them skipping a step on the checklist; nurses were also to ask them each day whether any lines ought to be removed, so as not to leave them in longer than necessary. This was revolutionary. Nurses have always had their ways of nudging a doctor into doing the right thing, ranging from the gentle reminder (“Um, did you forget to put on your mask, doctor?”) to more forceful methods (I’ve had a nurse bodycheck me when she thought I hadn’t put enough drapes on a patient). But many nurses aren’t sure whether this is their place, or whether a given step is worth a confrontation. (Does it really matter whether a patient’s legs are draped for a line going into the chest?) The new rule made it clear: if doctors didn’t follow every step on the checklist, the nurses would have backup from the administration to intervene.

Pronovost and his colleagues monitored what happened for a year afterward. The results were so dramatic that they weren’t sure whether to believe them: the ten-day line-infection rate went from eleven per cent to zero. So they followed patients for fifteen more months. Only two line infections occurred during the entire period. They calculated that, in this one hospital, the checklist had prevented forty-three infections and eight deaths, and saved two million dollars in costs.

Pronovost recruited some more colleagues, and they made some more checklists. One aimed to insure that nurses observe patients for pain at least once every four hours and provide timely pain medication. This reduced the likelihood of a patient’s experiencing untreated pain from forty-one per cent to three per cent. They tested a checklist for patients on mechanical ventilation, making sure that, for instance, the head of each patient’s bed was propped up at least thirty degrees so that oral secretions couldn’t go into the windpipe, and antacid medication was given to prevent stomach ulcers. The proportion of patients who didn’t receive the recommended care dropped from seventy per cent to four per cent; the occurrence of pneumonias fell by a quarter; and twenty-one fewer patients died than in the previous year. The researchers found that simply having the doctors and nurses in the I.C.U. make their own checklists for what they thought should be done each day improved the consistency of care to the point that, within a few weeks, the average length of patient stay in intensive care dropped by half.

The checklists provided two main benefits, Pronovost observed. First, they helped with memory recall, especially with mundane matters that are easily overlooked in patients undergoing more drastic events. (When you’re worrying about what treatment to give a woman who won’t stop seizing, it’s hard to remember to make sure that the head of her bed is in the right position.) A second effect was to make explicit the minimum, expected steps in complex processes. Pronovost was surprised to discover how often even experienced personnel failed to grasp the importance of certain precautions. In a survey of I.C.U. staff taken before introducing the ventilator checklists, he found that half hadn’t realized that there was evidence strongly supporting giving ventilated patients antacid medication. Checklists established a higher standard of baseline performance.

These are, of course, ridiculously primitive insights. Pronovost is routinely described by colleagues as “brilliant,” “inspiring,” a “genius.” He has an M.D. and a Ph.D. in public health from Johns Hopkins, and is trained in emergency medicine, anesthesiology, and critical-care medicine. But, really, does it take all that to figure out what house movers, wedding planners, and tax accountants figured out ages ago?


  1. "But, really, does it take all that to figure out what house movers, wedding planners, and tax accountants figured out ages ago?"

    No, but it may well take that amount of credibility within the relevant communities to move things along toward getting something done....

    cf. Direct Instruction and Project Follow Through (e.g. link )

  2. Disconcerting, since I would have imagined they did this anyway. I guess it's like that whole handwashing thing. Sounds simple once you start to actually do it.