Patient Safety Tip of the Week

October 26, 2010

Confirming Medications During Anesthesia


Many of the adverse events that occur in the operating room occur due to flawed processes. Many of those processes have counterparts outside the operating room where preventive measures have been instituted to successfully reduce the risk of the adverse events. Medication errors are one such area.


Most OR’s today remain very different from the rest of the hospital in several key respects from a patient safety perspective. For example, most do not have electronic medical records and, even if they do, those EMR’s may not be fully integrated with the EMR used by the rest of the hospital. Pharmacy IT systems are often not integrated with the OR. Bedside medication verification (barcoding) systems are not used in most OR’s. OR’s are particularly vulnerable to medication errors because the same person (i.e the anesthesiologist) is often responsible for ordering, dispensing and administering the medication. And the time pressures and emergency situations encountered in the OR further contribute to the occurrence of medication errors. Workarounds are also commonly used in the OR, often to save time and improve efficiency, but workarounds also introduce opportunities for error. One of the important patient safety tools used to prevent medication misadventures, particularly when dealing with high-risk medications, is the double-check process.


Our May 2008 What’s New in the Patient Safety World column “UK NPSA Alert on Heparin Flushes” cited a very good root cause analysis (Toft 2007) on several serious adverse events occurring in an anesthesia setting related to heparin misadministration. One of the many contributing factors uncovered in that RCA was the lack of double checks.


We’ve often discussed the controversial aspects related to double checks (i.e. that the second checker is more prone to error and, in fact, both checkers may be more prone to error because they assume the other checker correctly verified all the information). Further, the phenomenon of “involuntary automaticity” (Toft 2005) may occur whereby repeated use of the checking process becomes so ritualistic that true cognitive double checks are not being done. And the process of double checking  medications should be a “selective and systematic procedure” (Armitage 2007). However, studies have shown a roughly 30% reduction in drug errors with a double checking system.


So many have recommended that double checks be used to prevent medication errors in the OR and other situations using anesthesia. And a collaborative project in the UK has assessed the feasibility of confirming drugs administered during anesthesia. The study results were published in the British Journal of Anesthesia (Evley 2010). This study looked at two methods of confirming drugs during anesthesia: (1) a double-check system and (2) an electronic barcoding system. They concluded that, though both are feasible and likely to be effective in preventing medication errors, the double-check system has many obstacles that may make it impractical. On the other hand, the barcoding system was very practical and well-accepted into practice and provides a significant opportunity to reduce medication errors during anesthesia.


Details and additional materials from this study were released in an October 2010 data report from the UK’s National Patient Safety Agency. The study was not designed to quantify the number of medication errors but rather to determine the feasibility of using either of the two methods in the anesthesia setting. Five sites used a double-check method and 2 sites a barcoding method. Focused interviews, independent observers, and reflective diaries were used to collect data on the feasibility of each method. The NPSA data report includes many examples of actual comments made by the participants and these are most revealing.


While the double-check system (that is, having a second person confirm the correct drug is being given) was felt by most to be a valid theoretical concept and did also raise awareness of the problem of medication errors, too many disadvantages were noted. Most notable among these was the fact that a second person had to be available. That second person was not always immediately available, especially during emergent situations when medication errors are especially likely to occur. Others perceived that the double-check also introduced delays into the progress of cases. As a result, workarounds popped up. For example, multiple medications might be confirmed at the same time, something we strongly frown upon in patient safety. Worse yet, there were times when the anesthetist or anesthesiologist would avoid giving a clinically indicated medication because the double check protocol would have been too intrusive. The comments in the report are worth reading. In many cases, they reflect “culture of safety” issues or simple resistance to change rather than being directly related to the double check process. In fact, it is telling that most of the participants felt that, though medication errors during anesthesia do occur, they are seldom serious and are usually dealt with satisfactorily.


Use of an electronic barcoding system, on the other hand, was much better accepted. It was an accurate way of confirming the medications and obviously did not require the presence of a second person. A few disadvantages were technical ones easily fixed (eg. moving the scanner closer to the site where the IV medications were administered). A big advantage was that this particular barcoding system was part of an electronic medical record that made recording of all anesthesia events much easier and made the anesthesia record readily available to others (such as the team in the post-anesthesia area that would soon be receiving the patient).


But there were downsides as well. There was a learning curve and minor glitches often had to be worked out after implementation. However, most significantly, workarounds allow one to bypass the patient safety aspect of the barcoding system in much the same way that they occur elsewhere (see our June 17, 2008 Patient Safety Tip of the Week “Technology Workarounds Defeat Safety Intent”). These included not scanning medications before administering them, scanning multiple medications prior to administration, etc. The most obvious downside is the capital investment required to get a barcoding system implemented and integrated with the hospital’s pharmacy IT system and/or full EMR.


Though the study was not designed to demonstrate a reduction in actual medication errors in these settings (and realistically such a study is unlikely to get done soon due to the large number of patients and sites that would be needed), it does demonstrate that implementation of such systems is both feasible and practical.


Speaking of the OR, what about the ER! Almost all the comments we have made above apply equally to the emergency room. Many (we’ll even say most) hospitals that have implemented bedside medication verification (BMV) barcoding systems and computerized physician order entry (CPOE) systems and electronic medical records (EMR’s) on the inpatient side have not yet implemented these same patient safety features in either their OR’s or ER’s. Both sites deal not only with numerous medications but especially with high-risk medications. Should medication safety be less of an issue in those venues? Obviously not.







Toft B. Independent review of the circumstances surrounding four serious adverse incidents that occurred in the Oncology Day Beds Unity, Bristol Royal Hospital for Children on Wednesday, 3 January 2007. (UHBT Final Report Heparin). August 2007



Armitage G. Double checking medicines: defence against error or contributory factor? Journal of Evaluation in Clinical Practice 2008; 14(4): 513–519



Toft B, Mascie-Taylor H. Involuntary automaticity: a work-system induced risk to safe health care. Health Serv Manage Res 2005; 18: 211-216



Evley R, Russell, J, Mathew D, et al. Confirming the drugs administered during anaesthesia: a feasibility study in the pilot National Health Service sites, UK

Br. J. Anaesth. 2010; 105(3): 289-296



NPSA (UK). A collaborative project of the National Patient Safety Agency (NPSA), Royal College of Anaesthetists (RCoA) and Association of Anaesthetists of Great Britain and Ireland (AAGBI). Feasibility of confirming drugs administered during anaesthesia

A qualitative study in pilot NHS sites, England and Wales. October 2010















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