Background: Intravenous (IV) medication errors are frequent events. They are associated with considerable harm, but little is known about their causes. Human error theory is increasingly used to understand adverse events in medicine, but has not yet been applied to study IV errors. Our aim was to investigate causes of errors in IV drug preparation and administration using a framework of human error theory. Methods: A trained and experienced observer accompanied nurses during IV drug rounds on 10 wards in two hospitals (one university teaching hospital and one non-teaching hospital) in the UK. Information came from observation and talking informally to staff. Human error theory was used to analyse the causes of IV error. Results: 265 IV drug errors were identified during observation of 483 drug preparations and 447 administrations. The most common type of error was the deliberate violation of guidelines when injecting bolus doses faster than the recommended speed of 3–5 minutes. Causes included a lack of perceived risk, poor role models, and available technology. Mistakes occurred when drug preparation or administration involved uncommon procedures such as the preparation of very small volumes or the use of unusual drug vial presentations. Causes included a lack of knowledge of preparation or administration procedures and complex design of equipment. Underlying problems were the cultural context allowing unsafe drug use, the failure to teach practical aspects of drug handling, and design failures. Conclusions: Training needs and design issues should be addressed to reduce the rate of IV drug preparation and administration errors. This needs a coordinated approach from practitioners, regulators, and the pharmaceutical industry. |