Midway through a wound debridement, the scrub nurse noted that the sterilization indicators had not changed colors (indicating an inadequate sterilization process). A subsequent root cause analysis revealed that the sterile processing technician, at the end of his shift, forgot to push the button to start the autoclave. The next arriving technician did not notice that the sterilization indicator on the cart had not changed color, so he took the cart with the unsterile trays, and placed them on the shelf for use.
In 1999, the Institute of Medicine (IOM) highlighted two studies from the 1980s, which suggested that between 44,000 and 98,000 patients die every year due to preventable medical errors. The subsequent IOM report, Crossing the Quality Chasm, noted, “The current systems cannot do the job. Changing systems of care will.” The report went on further to describe the six aims of safety, effectiveness, efficiency, patient-centeredness, timeliness, and equity. With these aims, the IOM has defined the ultimate vision for the US health care system.
The limitations of the current health care system were further highlighted by Elizabeth McGlynn’s study in 2003, which demonstrated that patients only received 55% of the care warranted by medical evidence. Furthermore, they found that the likelihood that an individual patient would receive all appropriate care was only 2.5%.
A main contributor to the performance shortfall is the limitation of human performance. Table 18-1 illustrates expected human error rates in conditions of no undue time pressure or stress. Note that “under very high stress when dangerous activities are occurring rapidly,” the error rate can be as high as one in four (25%). Therefore, system designs that depend on perfect human performance are destined to fail at a very high rate. Furthermore, systems designed to function in conditions of high stress with frequent dangerous activities have a higher burden in order to ensure a favorable outcome.
TABLE 18-1Nominal Human Error Rates for Selected Activities |Favorite Table|Download (.pdf) TABLE 18-1 Nominal Human Error Rates for Selected Activities
|Activity (Assume no Undue Time Pressure or Stresses) ||Rate |
|Error of commission, eg, misreading a label ||.003 |
|Error of omission without reminders ||.01 |
|Error of omission when item is embedded in a procedure ||.003 |
|Simple arithmetic errors with self-checking ||.03 |
|Monitor or inspector fails to recognize an error ||.1 |
|Personnel on different shifts fail to check the condition of hardware unless directed by a checklist ||.1 |
|Error rate under very high stress when dangerous activities are occurring rapidly ||.25 |
As defined by the Federal Aviation Administration “human factors ...