Topic: Medication Error/Inattentional blindness/Tennessee Board of Pharmacy 2012 December News Letter

A pharmacist enters a prescription for methotrexate daily into the pharmacy computer.A dose warning appears on the screen. The pharmacist reads the warning, bypasses it, and dispenses the medication as entered. The patient receives an overdose of the medication and dies.

This error, and many more, have happened because the person performing the task fails to see what should have been plainly visible, and later, they cannot explain the lapse. People involved in these errors have been labeled as careless and negligent. But these types of accidents are common – even with intelligent, vigilant, and attentive people. The cause is usually rooted in inattentional blindness.

Accidents happen when attention mistakenly filters away important information and the brain fills in the gaps with what is aptly referred to as a "grand illusion." Thus, in the example above, the brain of the pharmacist filtered out important information on the computer screen,and filled in the gaps with erroneous information that led him to believe he had read the warning appropriately.

Inattentional blindness is more likely to occur if part of your attention is diverted to secondary tasks, like answering the phone while entering prescriptions into the computer, or even thinking about your dinner plans while transcribing an order.

Low workload causes boredom and reduces the mental attention given to tasks, as does carrying out highly practiced tasks, such as counting out medication. We spend a large majority of our waking life functioning with the equivalent of an automatic pilot, with occasional conscious checks to ensure tasks are being carried out properly. This makes us particularly prone to inattentional blindness.