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Patient Safety Tip of the Week

November 9, 2021   Ensuring Safe Site Surgery



It seems we’ve been doing a lot of columns recently on wrong site surgery or procedures (see our Patient Safety Tips of the Week for September 14, 2021 “Wrong Eye Injections” and October 5, 2021 “Wrong Side Again”). Despite all our efforts to eliminate “wrong site surgery” (which includes both wrong procedures and surgery or procedures on the wrong site, side, or patient), such incidents have not disappeared.


The Pennsylvania Patient Safety Authority put forth “Draft Recommendations to Ensure Correct Surgical Procedures and Correct Nerve Blocks” (PPSA 2021) on October 23, 2021 to prevent wrong-site surgery. These recommendations were approved by the (Pennsylvania) Department of Health. Public comments will be accepted by Patient Safety Authority for 30 days from that date of publication. The recommendations are listed below:


Recommendations to ensure the correct surgical procedure is done on the correct site, side and patient:

Preoperative verification and reconciliation

Site Marking—Site marking recommendations apply to all procedures where there is more than one possible location for the procedure.


Time-Out and Intraoperative Verification



·       Incorporate accountability for these recommendations into the facility's quality assurance and formal evaluation process. This includes both individual and team performance evaluations, ongoing professional practice evaluations, and focused professional practice evaluations.



Recommendations to ensure nerve blocks are performed at the correct site and correct patient:


Preoperative Verification and Reconciliation


Anesthesia Site Marking





·       Incorporate accountability for these recommendations into the facility's quality assurance and formal evaluation process. This includes both individual and team performance evaluations, ongoing professional practice evaluations and focused professional practice evaluations.



An article on wrong site surgery in ophthalmology last year (Parikh 2020) illustrates the importance of many of these recommendations. That study expands upon work previously done by John Simon that we’ve also discussed before (see our Patient Safety Tips of the Week for March 11, 2008 “Lessons from Ophthalmologyand May 17, 2016 “Patient Safety Issues in Cataract Surgery). The new study reported on 143 cases of “confusion” in ophthalmic surgery cases in New York State between January 1, 2006, and December 31, 2017. Two-thirds (66.4%) involved cases of incorrect implants being used during cataract surgery (cataract extraction and intraocular lens implantation). Wrong eye blocks or anesthesia accounted for 14.0%, incorrect eye procedures accounted for 7.00%, incorrect refractive surgery measurements accounted for 4.20%, incorrect patient or procedure accounted for 3.50%, incorrect intraocular gas concentration accounted for 2.80%, and incorrect medication in surgery accounted for 2.10%.


Of all cases, 92 (64.3%) were deemed preventable by the Universal Protocol in its current format. The leading root cause of surgical confusions among all the cases was an inadequately performed time out, which accounted for nearly one third of all surgical confusions (32.2%).


However, one salient feature of their work was that 33 of the incorrect implant cases (34.7%) were not preventable by the Universal Protocol. Many were the result of “upstream” errors, originating in the clinic or office before surgery. Errors from incorrect orders or calculations before the day of surgery were the second most common cause, accounting for nearly one quarter of surgical confusions (21.7%). They also noted a contributing factor we have emphasized in the past – change in the OR schedule. Other contributing factors included multiple lenses present in the OR, staff accidentally obtaining the incorrect lens power from the storage room, poorly labeled lenses, human error leading to errors despite properly performed time outs, and incorrect decisions by surgeons regarding toxic medications.


Our original foray into wrong site surgery 25 years ago that led to development of a timeout process followed cases of wrong intraocular lens implantation that included several of those root causes (change in the surgical schedule, presence of multiple lenses in the OR, etc.). We discuss the issue of change in surgical schedule later. And we extend the issue of multiple lenses in the OR to the presence of multiple records in the OR. Any time you have charts or records or images of more than one patient in the OR, you are vulnerable to using records from the wrong patient. If a surgeon brings all his office notes for the day’s cases, make sure they are kept somewhere outside the OR and that only those records on the case at hand are allowed in the OR one at a time.


Parikh et al. note that the Universal Protocol and time outs typically are performed before the case begins and key aspects may be forgotten at the time of lens implantation, which occurs toward the end of the surgery. For the time out to be maximally effective, it must occur shortly before the intended action.


Problems with site markings also contributed to some cases. Seven cases involved ambiguous site markings, which were washed off during surgical preparations, were covered, or otherwise were not visible. Another was simply not marked, and 2 were marked incorrectly. Patients themselves sometimes contributed by mistakenly affirming that they were having a procedure on the incorrect eye.


The authors stressed that “upstream” errors, originating in the clinic or office before surgery, and ineffective communication during time outs suggest a need for modification of the Universal Protocol. We discussed many of those “upstream” issues in our October 5, 2021 Patient Safety Tip of the Week “Wrong Side Again”.



Wrong-site nerve blocks have actually become the most common type of wrong-site surgery, accounting for 25.7% of cases of wrong-site surgery reported to the Pennsylvania Patient Safety Reporting System (PA-PSRS) from July 2004 to September 2017 (Arnold 2018).


Balocco et al. (Balocco 2019) described risk factors for wrong-side nerve blocks. These included both physician-related factors, patient-related factors, and procedure-related factors.

Physician-related factors:


Patient-related factors:


Procedure-related factors:


Notice that changes in the OR schedule again showed up as a significant risk factor. We cannot overemphasize the need to communicate to all parties when such changes take place. In that case that got us started over 25 years ago on preventing wrong-site procedures, a patient had complained he had expected to be the first case of the day. Staff sought to accommodate him by inserting him earlier into the schedule and that was a primary factor in leading to 2 consecutive patients receiving wrong intraocular lens implants. We recommend that you somehow flag that changes have occurred on your OR white board or electronic surgical schedule and especially communicate to all when such changes occur after the day’s original schedule was published.


Balocco et al. went on to discuss the use of checklists to help avoid wrong-side nerve blocks.


Vandebergh et al. recently described strategies to prevent wrong-side nerve blocks (Vandebergh 2021). They discuss the roles of checklists, procedural markings, the “Time Out” or “Stop Before You Block”, influence of the environment and team, and use of simulated procedures. They also discuss how new technologies, such as a USB device that attaches to the ultrasound probe and senses when the patient’s skin is touched, triggering an audible alert (“Check the side of the block”) that can only be stopped by pressing a confirmation button on the device.


They also discuss another intervention that we’ve discussed in multiple columns. That is including on the procedure kit or tray a sticker that requires a checklist be completed before the contents of the kit/tray can be removed.



Wrong-site surgery and wrong-site procedures are sentinel events that should never occur. We have a whole variety of tools and procedures to prevent such occurrences, but you have to use them and do so religiously. Failure to comply with the time out process or have everyone fully participate remains a major factor in wrong-site surgeries. And such participation must be active. Staff cannot simply nod concurrence. They must be able to go to primary source documents and confirm that the patient, procedure, site and laterality are correct.



Some of our prior columns related to wrong-site surgery:

  September 23, 2008 Checklists and Wrong Site Surgery

  June 5, 2007              Patient Safety in Ambulatory Surgery

  July 2007                  Pennsylvania PSA: Preventing Wrong-Site Surgery

  March 11, 2008         Lessons from Ophthalmology

  July 1, 2008              WHO’s New Surgical Safety Checklist

  January 20, 2009       The WHO Surgical Safety Checklist Delivers the Outcomes  

  September 14, 2010 Wrong-Site Craniotomy: Lessons Learned

  November 25, 2008 Wrong-Site Neurosurgery

  January 19, 2010       Timeouts and Safe Surgery

  June 8, 2010              Surgical Safety Checklist for Cataract Surgery

  December 6, 2010     More Tips to Prevent Wrong-Site Surgery

  June 6, 2011              Timeouts Outside the OR

  August 2011             New Wrong-Site Surgery Resources

  December 2011         Novel Technique to Prevent Wrong Level Spine Surgery

  October 30, 2012      Surgical Scheduling Errors

  January 2013             How Frequent are Surgical Never Events?

  January 1, 2013         Don’t Throw Away Those View Boxes Yet

  August 27, 2013       Lessons on Wrong-Site Surgery

  September 10, 2013 Informed Consent and Wrong-Site Surgery

  July 2014                  Wrong-Sided Thoracenteses

  March 15, 2016         Dental Patient Safety

  May 17, 2016            Patient Safety Issues in Cataract Surgery

  July 19, 2016            Infants and Wrong Site Surgery

  September 13, 2016 Vanderbilt’s Electronic Procedural Timeout

  May 2017                  Another Success for the Safe Surgery Checklist

  May 2, 2017              Anatomy of a Wrong Procedure

  June 2017                  Another Way to Verify Checklist Compliance

  March 26, 2019         Patient Misidentification

  May 14, 2019            Wrong-Site Surgery and Difficult-to-Mark Sites

  May 2020                  Poor Timeout Compliance: Ring a Bell?

  September 14, 2021 Wrong Eye Injections

  October 5, 2021        Wrong Side Again






PPSA (Pennsylvania Patient Safety Authority). Draft Recommendations to Ensure Correct Surgical Procedures and Correct Nerve Blocks. October 23, 2021



Parikh R, Palmer V, Kumar A, Simon JW. Surgical Confusions in Ophthalmology: Description, Analysis, and Prevention of Errors from 2006 through 2017. Ophthalmology 2020; 127(3): 296-302



Arnold TV. Update on Wrong-Site Surgery: More Data Provides More Insight. Pa Patient Saf Advis 2018; 15(1): 1-5



Balocco AL, Kransingh S, Lopez A, et al. Wrong-Side Nerve Blocks And the Use of Checklists. Part 1. Anesthesiology News 2019; October 19, 2019



Vandebergh V, Coll V, Keunen B. Prevention of Wrong-Side Nerve Blocks: Part 2. Anesthesiology News 2021; September 20, 2021






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