The 'vincristine error' occurs in the context of chemotherapy for ALL . It appears to be the most simplest of errors: a syringe mix-up between vincristine and methotrexate, leads to vincristine being given intrathecally instead of intravenously. The consequences are severe permanent neurological damage, and, more usually, death. It might be thought of as a freak, isolated occurrence; yet it is known to have happened at least 31 times around the world. In a report following a fatal outcome in England, over 40 system failures were described that contributed to the outcome. As a result, the error has emerged as an archetype among medical errors in the patient safety literature.

There are five stages in the sequence of events between ordering a drug and its delivery: prescription, transcription, dispensing, administration, and monitoring. The vincristine error occurs at the administration stage and is further classified as a misconnection error. This characterizes the final act in a multi-faceted process that historically has been described as a combination of human and systemic components. Ultimately, all problems originate at a human level, because the system is designed by humans. However, the human-system distinction is an important one to make, principally from the standpoint of understanding the multiple etiologies of error. Simply blaming people for bad outcomes is not a useful way to deal with error or to understand how it occurs.

The major determinants of safety within a system are the prevailing culture and the extent to which it embraces principles of human factors engineering. Culture overrides everything else. If the culture does not encourage people to understand the principles of patient safety and commit to them, then individual efforts will be mostly ineffective, and progress unlikely. Historically, the culture in medicine has been one of silence and perfection rather than one of sharing, understanding, and learning from error.

The medical workplace has been described as an 'ergonomic nightmare'. Human factors engineering combines an understanding of human psychological and physical performance on the one hand, with the physical characteristics and equipment of the workplace on the other. It is generally easier to design for physical rather than psychological characteristics. Human performance deficits are the principal cause of medication error; but this has to be interpreted within the context of specific behaviors in the medication process. Contextural issues include the characteristics of the immediate workplace (noise, lighting, temperature, space etc), equipment design and user-friendliness, workload/acuity, cognitive and affective load, fatigue, sleep deprivation/debt, multi-tasking demands, interruptions, distractions, and other sources of interference.

Studies of this error-archetype have provided insights into human performance and a continuing focus on the need for further development of strategies for improving patient safety.

Patrick Croskerry, MD, PhD Link to Personal Profile Associate Professor, Departments of Emergency Medicine and Medical Education Clinical Consultant in Patient Safety, Canadian Patient Safety Institute Dalhousie University Medical Education Pat Croskerry is a Clinical Consultant in Patient Safety, and Associate Professor in Emergency Medicine at Dalhousie University, Halifax, Nova Scotia, Canada. He holds a cross-appointment in the Faculty of Medical Education, and in 2002 was appointed a Senior Clinical Research Scholar at Dalhousie. In addition to his medical training, he holds a doctorate in Experimental Psychology with Fellowship training in Clinical Psychology. Link to Presenter's Biography Pat Croskerry is a Clinical Consultant in Patient Safety, and Associate Professor in Emergency Medicine at Dalhousie University, Halifax, Nova Scotia, Canada. He holds a cross-appointment in the Faculty of Medical Education, and in 2002 was appointed a Senior Clinical Research Scholar at Dalhousie. In addition to his medical training, he holds a doctorate in Experimental Psychology with Fellowship training in Clinical Psychology. Last Updated: 30 Jul 2007