The extent of medication errors and adverse drug reactions throughout the patient journey in acute care in Australia :

Interruptions have been implicated as a cause of clinical errors, yet, to our knowledge, no empirical studies of this relationship exist. We tested the hypothesis that interruptions during medication administration increase errors. We performed an observational study of nurses preparing and administering medications in 6 wards at 2 major teaching hospitals in Sydney, Australia. Procedural failures and interruptions were recorded during direct observation. Clinical errors were identified by comparing observational data with patients' medication charts. A volunteer sample of 98 nurses (representing a participation rate of 82%) were observed preparing and administering 4271 medications to 720 patients over 505 hours from September 2006 through March 2008. Associations between procedural failures (10 indicators; eg, aseptic technique) and clinical errors (12 indicators; eg, wrong dose) and interruptions, and between interruptions and potential severity of failures and errors, were the main outcome measures. Each interruption was associated with a 12.1% increase in procedural failures and a 12.7% increase in clinical errors. The association between interruptions and clinical errors was independent of hospital and nurse characteristics. Interruptions occurred in 53.1% of administrations (95% confidence interval [CI], 51.6%-54.6%). Of total drug administrations, 74.4% (n = 3177) had at least 1 procedural failure (95% CI, 73.1%-75.7%). Administrations with no interruptions (n = 2005) had a procedural failure rate of 69.6% (n = 1395; 95% CI, 67.6%-71.6%), which increased to 84.6% (n = 148; 95% CI, 79.2%-89.9%) with 3 interruptions. Overall, 25.0% (n = 1067; 95% CI, 23.7%-26.3%) of administrations had at least 1 clinical error. Those with no interruptions had a rate of 25.3% (n = 507; 95% CI, 23.4%-27.2%), whereas those with 3 interruptions had a rate of 38.9% (n = 68; 95% CI, 31.6%-46.1%). Nurse experience provided no protection against making a clinical error and was associated with higher procedural failure rates. Error severity increased with interruption frequency. Without interruption, the estimated risk of a major error was 2.3%; with 4 interruptions this risk doubled to 4.7% (95% CI, 2.9%-7.4%; P < .001). Among nurses at 2 hospitals, the occurrence and frequency of interruptions were significantly associated with the incidence of procedural failures and clinical errors.

Nurse staffing (fewer RNs), increased workload, and unstable nursing unit environments were linked to negative patient outcomes including falls and medication errors on medical/surgical units in a mixed method study combining longitudinal data (5 years) and primary data collection. Copyright © 2011 Elsevier Inc. All rights reserved.

1. To understand medication errors and to identify preventive strategies, we need to classify them and define the terms that describe them. 2. The four main approaches to defining technical terms consider etymology, usage, previous definitions, and the Ramsey-Lewis method (based on an understanding of theory and practice). 3. A medication error is 'a failure in the treatment process that leads to, or has the potential to lead to, harm to the patient'. 4. Prescribing faults, a subset of medication errors, should be distinguished from prescription errors. A prescribing fault is 'a failure in the prescribing [decision-making] process that leads to, or has the potential to lead to, harm to the patient'. The converse of this, 'balanced prescribing' is 'the use of a medicine that is appropriate to the patient's condition and, within the limits created by the uncertainty that attends therapeutic decisions, in a dosage regimen that optimizes the balance of benefit to harm'. This excludes all forms of prescribing faults, such as irrational, inappropriate, and ineffective prescribing, underprescribing and overprescribing. 5. A prescription error is 'a failure in the prescription writing process that results in a wrong instruction about one or more of the normal features of a prescription'. The 'normal features' include the identity of the recipient, the identity of the drug, the formulation, dose, route, timing, frequency, and duration of administration. 6. Medication errors can be classified, invoking psychological theory, as knowledge-based mistakes, rule-based mistakes, action-based slips, and memory-based lapses. This classification informs preventive strategies.