After the introduction of the Codonics SLS drug labeling system in 2 cardiothoracic ORs and the OR satellite pharmacy, a repeat audit found 312 syringes, of which 101 (32%) had been prepared by anesthesia providers, and 211 (68%) by the satellite pharmacy. All these syringes had a label. All the syringe labels prepared by the satellite pharmacy and 93% of the syringe labels prepared by the anesthesia providers were compliant. Anesthesia providers prepared 88% (89 of 101) of the syringe labels using the Codonics SLS system, which were all compliant. Twelve percent (12 of 101) of the syringe labels prepared by anesthesia providers were still made by hand, of which only 42% (5 of 12) were compliant. Of 12 syringe labels manually prepared by anesthesia providers, 50% (n = 6) were missing drug concentration, 17% (n = 2) were missing expiration date and time, and 8% (n = 1) had incorrect label color. Seventeen percent (n = 2) of syringe labels manually prepared by anesthesia providers had at least 2 label elements missing. None of the syringe labels prepared by anesthesia providers were illegible or used abbreviations. The OR satellite pharmacy prepared all the syringe labels using Codonics SLS system. Anesthesia providers exchanged 91% (192 of 211) of the usual pharmacy prefilled syringes containing traditional labels for the special pharmacy prefilled syringes containing Codonics SLS labels for the use in this study.
The average rate of scanning barcodes on syringe labels using SAM was 25% (730 drugs scanned out of 2976 drug administrations) over 13 weeks but increased to 58% (956 drugs scanned out of 1645 drug administrations) over the subsequent 8 weeks (P < 0.001) after introduction of a simple (coffee card) incentive (Figs. 7, 8 and 9). Nine anesthesia faculty members had significant differences in their rate of barcode scanning at the time of drug administration after the incentive (Fig. 7). There were relatively high and low performing attending physicians before and after the incentive. Before the coffee card incentive, 9% (65 of 730) of syringe barcode scans in the SAM database occurred after the drug administration time was recorded in the AIMS database, based on the time stamp of the barcode scan and the time of administration entered by the provider, and were not counted as successful scans in the rates reported above. Similarly, 10% (96 of 956) of syringe barcode scans after the coffee card incentive occurred after the drug administration time was recorded in the AIMS database and were not counted as successful scans in the rates reported above.
Technical issues that interfered with normal function of the Codonics system were tracked and are shown in Table 2.
Compliance of syringe labels prepared by anesthesia providers with the previously described recommendations from various regulatory agencies and standards-setting bodies (Table 1) has not been well studied. Our preintervention syringe audit demonstrated poor compliance, consistent with 2 previous reports.12,13 The use of the Codonics SLS drug labeling system resulted in complete compliance with labeling requirements when used by the anesthesia provider; the only labeling failures pertained to labels that were made by hand. The most likely reason for using hand labeling after introduction of the Codonics SLS system was technical issues we encountered with the system during the study (Table 2), although we did not specifically track the reasons for not using the Codonics SLS system. In addition, restriction of the second part of the syringe audit to the subset of the anesthesia providers and cardiothoracic ORs (because only 3 Codonics SLS units were available to us) may have introduced a selection bias. There are no prospective randomized studies showing that drug labeling practices directly reduce drug administration errors. However, human factors research suggests that strategic use of labels may reduce errors.14
While scientific validation of the labeling recommendations of the regulatory agencies and standards-setting bodies listed in Table 1 would be desirable, it is important to understand that hospitals may be held accountable for meeting certain regulatory requirements, even in the absence of scientific validation. For example, many American hospitals are subject to the requirements of TJC, whose syringe labeling recommendations are shown in Table 1. Hospitals are likely to expect their anesthesia providers to take a shared interest in meeting the necessary requirements.
Establishing the appropriate date and time of expiration for syringes prepared by anesthesia providers warrants further discussion. TJC standards do not require a date and time of expiration unless the expiration occurs before 24 hours from preparation. The Food and Drug Administration “package insert” for propofol states that propofol has a 6- or 12-hourh expiration time after being drawn up into a syringe. However, the United States Pharmacopeia [USP] Chapter <797> (standards for compounding sterile solutions)i states that drugs prepared outside an ISO Class 5 environment,j such as an OR, should be administered within 1 hour. Interestingly, only 65% of hospital pharmacies use USP <797> compliant cleanrooms according to a recent survey.15 Nevertheless, any organization wishing to be in compliance with USP <797> with respect to a 1-hour expiration of provider-prepared syringes would require a robust method for applying the date and time of expiration.
Route of administration is not addressed by any of the labeling recommendations in Table 1. Color labeling standards have been proposed to designate the intended route of administration (e.g., blue for IV and yellow for neuraxial);k however, to the best of our knowledge, these have not been reconciled with the internationally accepted syringe label colors pertaining to drug class. Confusion between neuraxial and IV injections ports is a potentially very serious route of administration error in anesthesia practice. There has been an effort to develop unique syringe connectors that would prevent a syringe containing a drug intended for the neuraxis to be connected to an IV port and vice versa.16,17
There are other possible methods for producing barcoded labels for syringes. Vials can be provided with peel-off or “flag” labels that can be transferred to the syringe. Preparation and expiration date/time and name of the preparer would have to be added by hand. The main disadvantage of this approach is that commercial drug vials are not usually available with flag labels, requiring the end-user to produce and add the labels. Another approach is to use commercially prefilled syringes with compliant labels. The main disadvantages for prefilled syringes are higher cost (Supplemental Digital Content 4, Table, http://links.lww.com/AA/A877, which compares the cost of drug vial acquisition at our institution and commercially available prefilled syringes) and limited availability. Finally, traditional anesthesia drug labels, usually supplied in rolls, could include a barcode; all other information except for the name of the drug would have to be entered by hand. The main disadvantage of traditional anesthesia drug labels is that the label is not physically associated with the vial, so vial swap or label swap errors can still occur.
We deliberately did not attempt to determine whether our system actually prevented errors. Measuring the incidence of drug administration error is difficult and requires a very large number of drug administrations to obtain adequate statistical power. Two previous studies of anesthetic drug error found that 30% of drug errors typically involved the misidentification of a drug vial or a syringe, either due to mislabeling or to a “swap” (correct label that is not read or is misread).18,19 Prevention of these types of errors may be possible by scanning the vial barcode, generating a corresponding syringe label containing a barcode, and then scanning the barcode on the syringe label immediately before drug administration. The evidence that scanning the barcode of a syringe just before drug administration reduces errors is not extensive.3,4 Several studies found significant reduction in drug administration errors after implementation of barcode technology in the intensive care units and hospital wards.20–23 Merry et al.2 conducted a prospective randomized trial of a comprehensive anesthesia drug safety system that included scanning the barcodes of syringes before drug administration but did not find a statistically significant difference between the rate of drug administration error when the drug safety system was used compared with that of conventional practice. However, they did note that the rate of error was lower when anesthesia providers consistently scanned the drug barcode before administration and kept the voice prompt active (6.0% vs 9.7%; P = 0.004). Unfortunately, the compliance with these 2 features was only 18%. Other studies of drug errors after the implementation of BCMA in the intensive care unit and hospital wards did not find reduction in errors,24,25 and some have identified unintended adverse consequences of barcode technology.26–28 A consensus group convened by the Anesthesia Patient Safety Foundation has recommended the use of barcode scanners in anesthesia practice.29 However, the results of our study and the study by Merry et al. suggest that consistent system use is a major obstacle to successfully implementing systems designed to improve safety, and that the ultimate effectiveness of such systems cannot be conclusively assessed without finding measures to insure a high level of use. In addition, unintended consequences and workarounds will have to be addressed and eliminated.
Convincing anesthesia providers to alter their work habits will generally require deliberate effort. Systems designed to improve safety will be accepted more readily and implemented more easily if they also improve efficiency. Recommended procedures are more likely to be followed if the staff members find that their job is made easier or more satisfying.30–32 Our syringe audit showed that our staff quickly adopted the routine use of the Codonics SLS drug labeling system, resulting in a high level of syringe labeling compliance. However, consistent use of scanning the barcode on the syringe at the time of drug administration was more difficult to achieve. Interviews with staff did not reveal any objection to the rationale for scanning the barcode or major problems with the process itself. The reasons for the low rate of barcode scanning appeared to be difficulty remembering to use the new process or lack of motivation. Belief that barcode scanning is not necessary, helpful, useful, or that it does not promote safety may be detractors.
Improving the drug preparation and administration workflow is an important consideration when implementing BCMA technology. The Codonics units were mounted on the left side of the anesthesia cart, which is next to the syringe preparation area without impacting the amount of space on top of the anesthesia cart. The Codonics software version used in the study required 14 seconds to print the labels (the current software version takes only 7 seconds). Although we did not measure the time required to draw a drug into a syringe, 14 seconds is sufficiently fast in our experience that the steps necessary to draw a drug into a syringe can be completed while the label is printing. Fraind et al.33 described 27 different steps in the process of IV bolus drug preparation including 2 steps for labeling a syringe (obtaining and attaching the label to the syringe). The new process using the Codonics units would replace the step of “obtaining a label” with scanning the vial and printing a label. However, the steps outlined by Fraind et al.33 do not include locating the drug label roll, peeling off the label and writing additional information on a label, which would have to be added to their list to produce compliant labels. Those additional tasks would not be necessary with the Codonics unit, because all the required information is printed automatically, therefore improving the workflow of drug preparation.
Fraind et al.33 also documented 14 steps in the process of administering an IV drug. Scanning the syringe with a barcode scanner would add another step to their list. However, the current drug documentation process using the AIMS at our institution without barcode scanning consists of 4 steps including selecting the drug menu on the main screen, scrolling through the list of drugs, selecting the drug, and entering the dose. Scanning the bar code with SAM actually shortens this process to 2 steps, scanning the barcode and entering the drug dose, because the drug entry screen is automatically brought up on the AIMS screen when the syringe bar code is identified.
Because some anesthesiologists and surgeons did not like the voice prompt that is intended to occur when a syringe label is scanned, staff members sometimes muted the sound on the workstation that is used for the AIMS. We believe that the voice prompt is important, because it enables the anesthesia provider to scan and administer the drug without constantly looking at the AIMS display screen. Without a voice prompt, wrong drug errors may go unrecognized if the anesthesia provider does not look at the display screen before administering the drug. Merry et al.2 also found that the voice prompt of the barcode scanner system was frequently disabled during their prospective evaluation of their multimodal drug safety system. Interestingly, while voice prompts have been widely used in airplane cockpits and for certain medical applications such as defibrillators, there are apparently no studies of voice prompts in the ORs. However, Botney and Gaba34 have discussed auditory prompts in general. There is evidence that alarms using voice are more effective than traditional alarms using sounds.35
To further improve the rate of syringe label barcode scanning, we tried a simple intervention that consisted of a contest in which we offered coffee cards to the attending staff with the highest rate of scanning syringe labels. The intervention was immediately and dramatically effective. While this approach of using an incentive may be useful, clearly a more sustainable approach is needed that will result in consistent use of bar coding at a rate of >90%. We can envision 2 alternative approaches that could be used, both of which would require alteration of our AIMS software. The first approach would be to make scanning the barcodes mandatory; drug menus would not be accessible without scanning a barcode. On rare occasions when a barcode was not available for a drug, open text entry could serve as a backup method of recording the drug in the record. The second approach would be to make the drug menus more difficult to access except by scanning a barcode; drug menus could be accessed from the AIMS screen manually but would be “buried” under several layers of selection keys, making barcoding a much easier method of entering a drug into the record.
Introduction of any new technology into clinical practice has the potential for causing unintended consequences. We were not aware of any particular unintended consequences during this study. Hypothetically, taking the time to make a syringe label could result in a delay in therapy during an emergency. However, it should be noted that TJC and other agencies allow for omitting the syringe label for a drug that is going to be administered immediately by the provider who has prepared the syringe. We did encounter 7 drug vials with barcodes that were not included in our Codonics barcode formulary and other minor systems issues (Table 2). Technical failures can affect the success of an otherwise well-conceived system. The barcode formulary does need to be maintained and updated regularly, because drug products are constantly changing. A backup method for producing compliant labels by hand should be immediately available during use of the Codonics system, because occasional failures are possible with any equipment.
A major limitation of our study is that we did not observe the staff to determine whether the syringe barcodes were scanned before or after drug administration. Some drugs were probably administered before scanning the barcode on the syringe while the anesthesia provider did not record the correct time of administration, in which case the barcode scan time stamp would be recorded as the time of administration. This is clearly a critical issue because only scanning the barcodes before drug administration provides an opportunity to avoid a syringe swap type of error. Studies with direct observation are needed to determine the true rate of appropriate scanning before drug administration; however, such studies are logistically difficult and expensive.
In conclusion, the anesthesia barcode drug administration system that we have described, consisting of the Codonics SLS drug labeling system and the SAM, could be used to achieve compliance with a set of syringe labeling requirements and to identify the drug by scanning the barcode at the time of drug administration. Obtaining high levels of compliance with scanning syringe label barcodes will probably require configuring the AIMS so that scanning the barcode on the syringe is much more convenient than entering drugs from a menu, or so that scanning the barcode is mandatory. Strong support from departmental leadership for safety initiatives may also be helpful. Testing the hypothesis that using barcode scanners to identify drug vials and syringes will actually reduce drug administration errors will require a large prospective randomized trial in which there is a high level of compliance with the prescribed use of the barcode scanners.
Name: Srdjan Jelacic, MD.
Contribution: This author helped design and conduct the study, collect the study data, analyze the data, wrote the manuscript, is the primary author of the manuscript, and is the author responsible for archiving the study files.
Attestation: Srdjan Jelacic has seen the original study data and approved the final manuscript.
Name: Andrew Bowdle, MD, PhD.
Contribution: This author helped design and conduct the study, collect the study data, analyze the data, and wrote the manuscript.
Attestation: Andrew Bowdle has seen the original study data and approved the final manuscript.
Name: Bala G. Nair, PhD.
Contribution: This author helped design and conduct the study, collect the study data, analyze the data, and wrote the manuscript.
Attestation: Bala G. Nair has seen the original study data and approved the final manuscript.
Name: Dolly Kusulos, RPh.
Contribution: This author helped design and conduct the study and write the manuscript.
Attestation: Dolly Kusulos reviewed the analysis of the data and approved the final manuscript.
Name: Lynnette Bower, PharmD.
Contribution: This author helped design and conduct the study and write the manuscript.
Attestation: Lynnette Bower reviewed the analysis of the data and approved the final manuscript.
Name: Kei Togashi, MD.
Contribution: This author helped analyze the data and write the manuscript.
Attestation: Kei Togashi has seen the original study data and approved the final manuscript.
This manuscript was handled by: Sorin J. Brull, MD, FCARCSI (Hon).
We would like to acknowledge Codonics Inc. (Middleburg Heights, OH), which provided Safe Label System units for our study. Codonics Inc., did not have any involvement in the design, study conduct, data collection or analysis, or manuscript preparation.
a Centers for Medicare and Medicaid Service (CMS): Stage 2 Overview Tipsheet. Available at: https://www.cms.gov/Regulations-and-Guidance/Legislation/EHRIncentivePrograms/Downloads/Stage2Overview_Tipsheet.pdf. Accessed January 22, 2014.
b Food and Drug Administration. Bar code label requirement for human drug products and biological products. Available at: http://www.gpo.gov/fdsys/pkg/FR-2004-02-26/pdf/04-4249.pdf. Accessed January 22, 2014.
c American Society of Anesthesiologists. Statement on Labeling of Pharmaceuticals for Use in Anesthesiology. Available at: http://www.asahq.org/for-members/standards-guidelines-and-statements.aspx. Accessed January 22, 2014.
d The ISO 26825:2008 standards are not freely available, but can be purchased online at ISO.org.
e The full version of the ASTM D4774 standards is not freely available, but can be purchased online at ASTM.org (an abbreviated version of ASTM D4774 is freely available at: http://www.astm.org/Standards/D4774.htm; accessed January 22, 2014).
f To make a dilution label, the provider first pressed the “dilute” button on the main touchscreen to turn the dilution function on. Next, the drug vial barcode was scanned. After the drug name was confirmed with auditory feedback, the dilution screen presented the provider with common dilution concentrations and diluent options. After the provider selected appropriate dilution concentration and diluent for the drug, the label was printed.
g A.F. Merry and C.S. Webster were the first to use a recorded voice to announce the drug name following scanning the barcode on the syringe in the anesthesia workplace.
h Advice contained in package inserts regarding expiration times for propofol is not entirely consistent. Expiration times of both 6 and 12 hours may be found in these documents. We reviewed current FDA approved package inserts for propofol found on a US government website: http://dailymed.nlm.nih.gov/dailymed/search.cfm?startswith=propofol&x=14&y=11. Applicable package inserts included those from AstraZeneca Pharmaceuticals, Fresenius Kabi USA, and APP Pharmaceuticals. AstraZeneca’s package insert (dated “Rev 08/05”) recommends propofol that has been drawn from a vial into a syringe should be discarded within 6 hours, whereas vials used for continuous infusion should be discarded within 12 hours. Fresenius Kabi USA does not make any distinction between propofol drawn into syringes and propofol vials used for continuous infusion, stating that both should be used within 12 hours (April 2013, pertaining to their product that does include an antimicrobial retardant). A “Health Care Provider Letter” issued by APP Pharmaceuticals (June 19, 2012) regarding Fresenius Propoven 1%, which does not contain any anti-microbial retardant, states that Fresenius Propoven 1% should be discarded within 6 hours of being drawn into a syringe, and that “propofol 1% used for IV infusion” should be discarded within 12 hours, along with the infusion system.
i US Pharmacopeia. USP-NF General Chapter <797> Pharmaceutical Compounding - Sterile Preparations. Available at: http://www.usp.org/store/products-services/usp-compounding. Accessed on January 22, 2014.
j The air in an ISO Class 5 environment must contain no more than 100 particles per cubic foot (3520 particles/m3) and typically requires a “biological safety cabinet” or “clean room” in which the air is filtered.
k Australian Commission on Safety and Quality in Health Care. National Recommendations for User-applied Labeling of Injectable Medicines, Fluids and Lines. Available at: http://www.safetyandquality.gov.au/wp-content/uploads/2012/02/Labelling-Recommendations-2nd-edition-February-2012_PRESS.pdf. Accessed July 22, 2014.
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