Pediatric Informatics: Computer Applications in Child Health (Health ...

29 Understanding and Preventing Errors 375
29.5 Error Proofing
Both RCA and FMEA help identify risk points and contributors to failure. Although
both approaches imply that countermeasures or corrective actions will be taken to
prevent recurrence and lower the risk of failure overall, neither approach offers
tools to guide the improvement process. In looking at failures in complex systems
involving the action of individuals, human error is a special case that requires particular
consideration. Even when multiple contributors outside the realm of error
contribute to failure, human error is often a proximate cause of the failure.
By recognizing certain patterns or types of error, it is possible to identify specific
strategies to reduce the risk of error or the consequences of errors. These strategies
can be incorporated into the design of systems including the design of information
systems. Takeshi Nakajo 22 recognized that tasks require sets of specific functions.
When those functions are not applied correctly, tasks are not completed correctly
and an error occurs. Error prevention strategies work to minimize the likelihood of
occurrence. Although not all errors cause consequences, some do result in abnormalities
that can be identified. In some cases, those abnormalities reflect harm
of some sort. In other cases, there may be a warning between the occurrence of
that abnormality and harm. Even when errors occur, strategies that minimize their
effects can also protect patients from harm. This schema is illustrated in Fig. 29.3.
The functions that are called upon for task completion include: memory, perception,
attention, judgment, and motion (or action). In the narcotic overdose example
above, the task of refilling the medication cassette in the infusion pump might have
required each of these. The nurse might have been required to remember the correct
drug formulation and dose if it were not available at the point of drug dispensing.
She would have needed to perceive or recognize that the medication she chose was
of a different concentration than intended. She exercised judgment in choosing
an alternative strategy in overriding safety checks on the drug dispensing system
when the correct formulation was unavailable. Actions were required to check the
Tasks/
Risks
Functions
Eliminate Replace Facilitate
Prevent occurrence
Fig. 29.3 Error proofing strategies
memory
perception
attention
judgment
motion/action
Error/Failure
Abnormalities Effects
Detection
Minimize Effect
Mitigate/
Rescue