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Patient Safety Tip of the Week

June 9, 2020   Perioperative Medication Safety



Medication safety is a primary concern in almost every venue of our healthcare delivery system. But the OR and the perioperative period have unique circumstances that increase the vulnerability for medication errors. Common factors predisposing to medication errors in this environment are:

·       Lack of a second set of eyes
Often, one individual (the anesthetist) is responsible for ordering, preparing, administering, and monitoring a medication in the OR. This bypasses the opportunities we typically see elsewhere where a second or third individual (eg. nurse, pharmacist) can spot an error and intervene before the error reaches the patient.

·       Lack of many of the medication safety tools we use outside the OR (eg. bedside medication verification with barcoding)

·       Lack of IT safety tools
Many OR information systems are still not interactive with the main hospital electronic medical record (EMR) and computerized physician order entry (CPOE) systems so the opportunity to utilize clinical decision support (CDS) tools may not be available in the OR

·       The final line of defense, the patient himself or herself, often cannot participate in safety activities because he/she is under the influence of anesthesia or other medications that cloud cognition

·       Handoffs (eg. pre-anesthesia to OR, OR to PACU, PACU to ICU, etc.) are opportunities for communication failures

·       Patients undergoing surgery or procedures often have complicated medical problems and many of their previous medications (or meals) may have been held prior to surgery

·       The OR is a complex environment, where distractions and interruptions are common

·       Multitasking is common in the OR and other perioperative settings

·       The OR functions as a team and sometimes communications and coordination within the team are suboptimal

·       Supplies may not be immediately available

·       Many orders in the OR are verbal orders, which are prone to miscommunication and incompleteness

·       Dare we mention hierarchy, egos and lack of a culture of safety?


Probably the most telling story about perioperative medication safety was a study from the Massachusetts General Hospital (Nanji 2015) that we discussed in our November 3, 2015 Patient Safety Tip of the Week “Medication Errors in the OR - Part 2. In fact, one in every 20 perioperative medication administrations resulted in a medication error or adverse drug event. The overall rate of 5.3% is pretty close to the rates we typically see on inpatient units. And almost half of all surgery cases had at least one medication error or adverse drug event.


A recent AORN review (Spruce 2020) of perioperative medication safety identified several other factors contributing to medication errors in the perioperative environment:

·       a lack of standardized documentation systems which may affect medication order transcription

·       health care personnel fatigue related to work and call schedules

·       time-sensitive medication administration to address a patient’s condition

·       the removal of medication from the original manufacturer’s packaging for aseptic delivery to the sterile field

·       multiple individuals may handle medications on sterile fields before administration

·       a lack of standardized medication-labeling practices

·       a lack of oversight by a licensed pharmacist

·       distractions during medication preparation and administration

·       some orders may be handwritten rather than entered via CPOE, handwritten orders being more prone errors such as use of inappropriate abbreviations


The Spruce review further notes that pediatric patients undergoing surgery are at an increased risk for medication errors because of weight-based dosing calculations and dilutions.


Among the recommendations in the Spruce review:

·       Health care facility leaders should form an interdisciplinary team (ie, a medication safety committee) to develop, provide implementation oversight of, and evaluate the perioperative medication management plan.

·       Perioperative leaders should work with pharmacy supply chain staff members to procure medications in single-use vials and prefilled syringes when possible.

·       Perioperative personnel may find it helpful to have the medications provided for them in commonly requested amounts and volumes and with limited variations in medication strengths and concentrations.

·       Medications stored in specialty or emergency carts should be organized with safety considerations in mind.

·       When creating storage locations for emergency medications, perioperative nurses should work with pharmacy staff members to ensure that high-alert medications are separated from each other using bins and containers, all medications are labeled and not stored alphabetically, and generic and brand names are indicated with tall man lettering


One of the biggest vulnerabilities to serious medication errors in the OR is related to maintenance of the sterile field. Medications transferred to the sterile field are sometimes drawn from unlabeled containers or are in syringes that are unlabeled. In addition, the presence of multiple syringes in the sterile field may lead to syringe “swapping” errors. A recent review of incorrect administration of neuromuscular blocking agents (NMBA’s) during spinal or epidural anesthesia (Patel 2020) found syringe swap was the primary cause for the majority of errors. Unlabeled syringes were one factor in accidental spinal injections discussed in our July 9, 2019 Patient Safety Tip of the Week “Spinal Injection of Tranexamic Acid”.


The Spruce review has good recommendations to avoid medication errors related to the sterile field:

·       obtain and prepare one medication for one patient at a time

·       transfer only one medication at a time to the sterile field

·       verbally verify each medication with the scrub person and include the medication name, strength, dosage, and expiration date

·       transfer medication to the sterile field using aseptic technique

·       use sterile transfer devices or syringes to transfer medications from vials to the sterile field rather than removing rubber stoppers unless the stopper is designed to be removed (eg, has a removable metal band)

·       collaborate with the scrub person to ensure all containers and syringes on the sterile field that contain medications, solutions, chemicals, and reagents are labeled immediately after transfer to the sterile field with the medication name, strength, dilution (and diluent, if used), date, and time the medication expires, if less than 24 hours

·       ensure labels only include approved abbreviations and dose expressions

·       encourage use of tall man lettering for container labels when medications have look-alike names


The Spruce review also discusses precautions that must be taken if any medications must be compounded or multiple medications mixed.


Regarding handoffs, medication reconciliation needs to take place at all transitions of care. That includes transitions like transfer from the pre-op area to the OR, from the OR to the PACU, from the PACU to the ICU or med/surg unit. It’s especially important to pay attention to any IV lines that may be connected to sources of medications. A good checklist for such transitions of care would contain an item about checking those IV lines. Note that transitions of care apply not only to transfers of the patient from one location to another. In fact, the staff may change in the OR itself (for example, nursing staff or anesthesiology staff may occasionally change in cases of long surgical duration). Those transitions are also vulnerable periods for medication errors as well as other errors. And don’t forget that the medication reconciliation must extend beyond just the last transition of care. For example, many medications are withheld prior to anticipated surgery and need to be restarted after completion of the surgery and PACU recovery period.


Just as elsewhere in the healthcare system, look-alike sound-alike (LASA) issues may lead to medication errors in the OR. Given the stresses, time pressures, distractions and interruptions commonly occurring in the OR setting, it is not surprising that someone may grab an incorrect vial that has an appearance similar to the intended one. Similarity of ampules of tranexamic acid and local anesthetic agents were a factor in accidental spinal injections discussed in our July 9, 2019 Patient Safety Tip of the Week “Spinal Injection of Tranexamic Acid”.


It’s not surprising that, in the heat of the moment, someone might grab the wrong medication from an anesthesia cart or an automated dispensing cabinet (ADC). See our January 1, 2019 “More on Automated Dispensing Cabinet (ADC) Safety” and other columns on ADC issues. It’s critical that high alert medications, in particular, be appropriately identifiable and appropriately segregated to prevent such inadvertent occurrences.


Irrigation fluids have been involved in perioperative medication errors. In some cases, they may have been in unlabeled basins on the sterile field. In others, the may have been in bags intended for irrigation of certain sites (eg. bladder irrigation) and were instead connected to IV lines.


Another recent review of perioperative medication safety (Redman 2020) cited the work of Wahr et al. (Wahr 2017) that we discussed in our June 4, 2019 Patient Safety Tip of the Week “Medication Errors in the OR – Part 3”. Wahr et al. did a literature review and found 138 unique recommendations for OR medication safety, then used a modified Delphi process to whittle the list down to 35 specific recommendations. We refer you to Table 4 in the Wahr review for the full list of the 35 recommendations. Redman highlighted several of these:

·       labeling medications with the name, date, and concentration

·       avoiding using abbreviations on medication labels

·       discarding unlabeled syringes

·       using prefilled syringes whenever possible

·       compounding and diluting medications in a pharmacy

·       double-checking provider-prepared high-risk medications, preferably with a second person

·       verifying high-risk and weight-based medication dosages with a second person

·       using aseptic technique when capping syringes or injecting medications

·       reading and verifying all medication labels (eg, on vials, on syringes) before administration

·       using standardized smart pumps for all infusions

·        passing one medication to the sterile field at a time

·       segregating noninjectable solutions (eg, irrigation fluids)

·       reviewing administered medications during patient hand overs

·       verifying verbal medication orders (eg, repeating exact information, announcing when administration is complete)

·       discarding all medication containers at the completion of the procedure unless they are connected to the patient.


Redman stresses the importance of proper labeling. She cites an interesting simulation study done by Estock and colleagues (Estock 2018). In the latter study, anesthesia trainee participants were randomly assigned to either redesigned labels or the current label condition. In the simulation, the surgeon asked the participant to administer hetastarch to the simulated patient because of hemodynamic instability. The fluid drawer of the anesthesia cart contained three 500-ml intravenous bags of hetastarch and one 500-ml intravenous bag of lidocaine. The percentage of participants who correctly selected hetastarch from the cart was significantly higher for the redesigned labels than the current labels (63% versus 40%; odds ratio, 2.6). They concluded that using opaque, white 2-sided medication labels on IV bags with white text on a dark background was effective.


Monitoring is one of the most important aspects of medication safety in any venue. Patients in the OR and PACU often have monitoring that is as good or better than that done on a typical ICU patient. But monitoring is complicated by the myriad of things that can happen in the OR. For example, the occurrence of tachycardia in a patient in the OR could be a sign of an allergic medication reaction or other adverse medication effect. But it could also be due to blood loss, arousal from anesthesia, or rare conditions like malignant hyperthermia, latex allergy or LAST (local anesthetic systemic toxicity) as discussed below. Moreover, the person charged with doing most of the monitoring – the anesthetist – is often multitasking and may be distracted from key changes in monitored parameters.


Workarounds may lead to medication accidents as well. For example, an anesthetist might find it a timesaver to draw up medications from multiple vials in one setting. But that can lead to mislabeling of the syringes. Proper technique would be to draw up the medication from one vial and label that syringe before going on to the next. Workarounds should always make you look for a root cause. A root cause in this example would be lack of prefilled syringes.


We mentioned that one problem commonly encountered is that certain supplies or medications may not be readily available in the OR, leading to harried attempts to procure that medication. But the opposite problem can also occur. That is, the inappropriate presence of an unnecessary medication can lead to accidental use of that medication. Our columns on the “ophthalmology blue dye accidents” (see our columns from May 20, 2014 “Ophthalmology: Blue Dye Mixup” and September 2014 “Another Blue Dye Eye Mixup”) discussed cases where methylene blue dye was erroneously used in eye surgery instead of trypan blue. There is actually little reason to keep methylene blue in most OR setups since it is used only in a few select instances. Similarly, the tranexamic acid incidents (see our July 9, 2019 Patient Safety Tip of the Week “Spinal Injection of Tranexamic Acid”) might have been avoided because tranexamic acid is only used for a few procedures, raising the question why it would even be included in most OR setups.


LAST (local anesthetic systemic toxicity) is a syndrome that has only relatively recently gained increased recognition, which may be life-threatening (Weinberg 2010, Weinberg 2020, El-Boghdadly  2018). CNS manifestations are most common, with seizures being the most common manifestation. However, early manifestations have been quite diverse. Perioral paresthesia, confusion, audio–visual disturbances, dysgeusia, agitation, or reduced level of consciousness, and cardiovascular manifestations may include dysrhythmias, conduction deficits, hypotension, and eventually cardiac arrest. Note that the cardiovascular manifestations often occur while the patient is under general anesthesia or heavy sedation where CNS toxicity is difficult to ascertain. We refer you to the articles above for discussion of treatment, which focuses on airway management, seizure suppression, circulatory support, and the role of infusion of lipid emulsion.


Finally, though it’s not technically “medication” safety, latex allergy is a safety issue in the OR and perioperative setting that certainly comes into the differential diagnosis of medication-related issues. In our July 6, 2020 Patient Safety Tip of the Week “Book Reviews: Pronovost and Gawande” we described an excerpt from Peter Pronovost’s book “Safe Patients, Smart Hospitals: How One Doctor's Checklist Can Help Us Change Health Care from the Inside Out” in which he describes a harrowing experience where he, as the anesthesiologist, correctly suspected a deteriorating patient had a potentially life-threatening latex allergy during surgery. He implored the surgeon in every way possible to change his gloves to non-latex ones and the surgeon refused until Pronovost put out a page to the hospital administration!


In our August 16, 2011 Patient Safety Tip of the Week “Crisis Checklists for the OR” we discussed an article by Ziewacz and colleagues (Ziewacz 2011) about having ready access to checklists for managing less common crises in the OR, such as malignant hyperthermia. We’d suggest you consider adding checklists for LAST and latex allergies to your list of crisis checklists for the OR.


We hope you’ll go back to our series of medication errors in the OR (March 24, 2009 “Medication Errors in the OR”, November 3, 2015 “Medication Errors in the OR - Part 2” and June 4, 2019 “Medication Errors in the OR – Part 3”) which had very good recommendations from ISMP (Institute for Safe Medication Practices) (ISMP 2015), PPSA (Pennsylvania Patient Safety Authority) (Cierniak 2018), AORN (Association of periOperative Registered Nurses) (Novak 2015, Litman 2018, Sones 2019, Boytim 2018), and APSF (Anesthesia Patient Safety Foundation) (APSF 2012), among others.


And it goes without saying that every attempt should be made to extend our medication safety tools to the OR. That includes integration of the OR information system with the facility-wide EMR and CPOE, use of barcoding for medication verification, use of standardized doses and pre-filled syringes, use of smart pumps, having a clinical pharmacist as part of the team, and others.



Some of our prior columns on medication errors in the OR:


March 24, 2009           Medication Errors in the OR

May 20, 2014              Ophthalmology: Blue Dye Mixup

September 2014          Another Blue Dye Eye Mixup

November 3, 2015      Medication Errors in the OR - Part 2

June 4, 2019                Medication Errors in the OR – Part 3

July 9, 2019                Spinal Injection of Tranexamic Acid






Nanji KC, Patel A, Shaikh S, Seger DL, Bates DW. Evaluation of Perioperative Medication Errors and Adverse Drug Events. Anesthesiology 2015; October 2015 Newly Published on 10 2015



Spruce L. Back to Basics: Medication Safety. AORN Journal 2020; 111(1): 103-112


Patel S. Erroneous neuraxial administration of neuromuscular blocking drugs, European Journal of Anaesthesiology 2020; Published Ahead of Print May 05, 2020



Redman DD, Perioperative Medication Safety: A Continuing Challenge. AORN Journal 2020; 111(1): 116-120

(Redman 2020)



Wahr A, Abernathy JH, Lazarra EH. Medication safety in the operating room: literature and expert-based recommendations. British Journal of Anaesthesia 2017; 118 (1): 32-43



Estock JL, Murray AW, Mizah MT, et al. Label design affects medication safety in an operating room crisis: a controlled simulation study. J Patient Saf. 2018;14(2): 101-106



Weinberg GL. Treatment of local anesthetic systemic toxicity (LAST). Reg Anesth Pain Med 2010; 35: 188-193



Weinberg G, Rupnik B, Aggarwal N, et al. Local Anesthetic Systemic Toxicity (LAST) Revisited: A Paradigm in Evolution. APSF (Anesthesia Patient Safety Foundation) Newsletter 2020; 35(1): 1, 5-7



El-Boghdadly K, Pawa A, Chin, KJ. Local anesthetic systemic toxicity: current perspectives. Local and Regional Anesthesia 2018; 11: 35-44.



Ziewacz JE, Arriaga AF, Bader AM, Berry WR, et al. Crisis Checklists for the Operating Room: Development and Pilot Testing. J Am Coll Surg 2011; 213(2): 212-219



ISMP (Institute for Safe Medication Practices). Key vulnerabilities in the surgical environment: Container mix-ups and syringe swaps. ISMP Medication Safety Alert! Acute Care Edition 2015; November 5, 2015



Cierniak KH, Gaunt MJ, Grissinger M. Perioperative Medication Errors: Uncovering Risk from Behind the Drapes. Pa Patient Saf Advis 2018; 15(4).



Novak R. Best Practices in Drug Safety. Expert advice on proper medication storage, security and labeling. Outpatient Surgery 2015; October 2015



Litman R. Tools to Improve Medication Safety. To eliminate administration mistakes, you have to eliminate the human factor. Outpatient Surgery 2018; July 2018



Sones S. Your Prescription for Medication Safety. Our pharmacy consultant dispenses indispensable advice. Outpatient Surgery 2019; XX No. 4; April 2019



Boytim J, Ulrich B. Factors contributing to perioperative medication errors: A systematic literature review. AORN J 2018; 107(1): 91-107



APSF (Anesthesia Patient Safety Foundation). Medication Safety in the Operating Room: Time for a New Paradigm. January 2012





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