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Wrong-side Bedside Paravertebral Block: Preventing the Preventable

Michael J. Barrington, MBBS, PhD, and Yoshiaki Uda, MBBS | April 1, 2017
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The Case

An 84-year-old woman presented to the emergency department following a mechanical fall at home. The fall occurred as she attempted to sit down in the bathroom and missed the toilet, falling backwards and striking her right back and flank against the bathtub. Imaging demonstrated multiple right-sided rib fractures.

The patient was admitted to the medical-surgical ward. On the first hospital day, the patient continued to have difficulty with maximal inspiration because of pain associated with the rib fractures. The clinical team decided to obtain an anesthesia consultation to place a paravertebral block. The anesthesiologist performed the block on the patient while she was in her bed. At the completion of the block, postprocedure imaging was performed to rule out complications. It was then that the performing physician realized that the fractures were on the opposite side—which meant that the block had been placed on the wrong side. This was then confirmed by reviewing the chart.

On review of the case, it was noted that the personnel carrying out the procedure at the bedside had not performed the usual safety checks or a "time out" to identify the correct side.

The patient required an additional paravertebral block on the correct (right) side to control the pain, increasing her chances of postprocedure complications, including bleeding and pneumothorax. Because of the error, the patient was exposed to unnecessary additional medication, and the institution bore unnecessary additional costs for the additional local anesthesia, regional block instrument tray, and personnel (the patient was not charged for the repeat procedure).

The Commentary

by Michael J. Barrington, MBBS, PhD, and Yoshiaki Uda, MBBS

The case presented provides an opportunity to reflect on medical errors and issues pertinent to performing major regional anesthesia procedures.

Wrong-site procedures can cause patient harm, which may result in increased costs and loss of trust in health care.(1) Wrong-site procedures include surgical or other invasive procedures performed on the wrong side, wrong body part, wrong patient, or wrong procedure at the correct site.(2) Wrong-site errors commonly involve symmetrical structures and are often wrong-sided errors.(3) Wrong-site procedures are medical errors that are considered never events, since they have long been included on the National Quality Forum's list of events that "should never happen."(4)

Wrong-site surgical and anesthesia procedures have been subject to extensive scrutiny. The incidence of wrong-site surgery is estimated to be 0.09 to 4.5 per 10,000 procedures (2), while the incidence of wrong-site regional anesthesia is in the range 1.46 to 7.48 per 10,000 blocks.(5) Few studies exist on wrong-site procedures performed outside of the operating room (OR). In two studies conducted by the United States Veterans Affairs Medical Centers between 2001 and 2009, nearly half of the incorrect procedures (wrong procedures on the correct site, wrong implant, wrong-site errors) were performed outside of the OR. These locations included clinics, emergency or radiology departments, interventional procedure rooms, or at the bedside.(6,7)

Paravertebral blockade is a major regional anesthesia procedure, and the anesthesiologist must pay meticulous attention to indication, anatomy, equipment, and technique. The environment where paravertebral block and other major regional anesthesia procedures (such as epidural blockade) are performed is paramount.(8) The same level of lighting, physical space, monitoring, assistance, and availability of resuscitative equipment present in the OR should be available in any environment where an invasive procedure is performed. Because of the challenges in replicating the OR environment in remote locations, many facilities centralize their resources to the OR or a specified procedural area. Following paravertebral blockade, patient monitoring for adverse effects or complications is required and is usually done in a high-intensity area such as a postanesthesia care unit.

The current safety standard for preventing wrong-site procedures is The Joint Commission's 2004 Universal Protocol. This protocol is advocated for any invasive procedure performed in any location and is comprised of three minimum requirements: a preprocedural verification of the correct patient and procedure, a surgical site marking that involves the patient before he or she is sedated, and routine implementation of a time-out involving all team members.(9) The importance of a team time-out is also emphasized in the World Health Organization Safe Surgery Checklist.

Despite the introduction of the Universal Protocol, wrong-site errors or near misses continue to occur, both inside and outside of the OR.(10,11) Root cause analyses indicate that errors stem from both system failure and human factors. These root causes include lack of adherence to protocols, deficiency in education, lack of experience in the planned procedures, poor teamwork and communication, poor interpersonal dynamics, distraction, fatigue, time and production pressure, cognitive overload, and reduced situational awareness.(3,11)

The wrong-sided bedside paravertebral block in this case may have resulted from many factors, including cognitive overload due insufficient ward staff understanding of the procedure, need to manage a suboptimal procedural environment, poor interpersonal dynamics, haste, time pressure, and lack of situational awareness. The paravertebral space is symmetrical and close to the midline, which renders paravertebral blockade prone to left–right confusion and wrong-sided errors. In the current case, it is unclear if the safety procedures mandated by the Universal Protocol were carried out. The protocol requires the correct site to be verified by a minimum of two staff members. Site verification and marking should occur by reconciling all critical information including history, examination, imaging, and the consent form. Informed patient consent includes a discussion and documentation of benefits, risks, and alternatives to the planned procedure. Patient pain, sedation, cognitive impairment, or a language barrier can impede site verification and informed consent. Therefore, involving a patient's family member or a qualified interpreter in both consent and site verification may reduce the risk of error.

Failure to perform a team time-out is a recognized cause of wrong-site error.(10,11) In the context of a regional anesthesia procedure, a team or block time-out should occur immediately prior to needle insertion and involve a minimum of two staff members. During the time-out, the anesthesiologist should create an environment resembling aviation's "sterile cockpit," meaning that all nonessential activities and conversations cease. The site marking and the consent form should be visualized again at this stage to confirm the correct patient, correct procedure, and correct site; these efforts should involve the patient if he or she is still alert. A team or block time-out should be repeated if there is any delay or distraction, change in patient position, or before a second invasive procedure. This process is endorsed by the widely adopted United Kingdom national safety initiative titled "Stop Before You Block."(12) It is critical to understand that the time-out is the final check of multiple redundant checks to independently verify existing information and to ensure the team is doing the correct procedure on the correct patient.(3)

This case of wrong-side bedside paravertebral block exemplifies why multiple steps and processes including checklists should be routine in every location where an invasive procedure is performed.(3) The American Society of Regional Anesthesia and Pain Medicine created a nine-point checklist for regional anesthesia procedures incorporating Universal Protocol principles.(13) Providers should be aware of factors that reduce human performance (including distraction, fatigue, time and production pressure, poor communication, reduced situational awareness, and cognitive overload) and of strategies to mitigate these factors. The abovementioned processes require clinical leadership and medical staff should be proactive in adhering to protocols and checklists.

Take-Home Points

  • Wrong-site errors are considered never events and represent a core patient safety problem.
  • The current safety standard for preventing wrong-site errors includes The Joint Commission Universal Protocol and the World Health Organization Safe Surgery Checklist. These protocols and checklists should be implemented in any location in any hospital where an invasive procedure is performed.
  • Preprocedural site verification, site marking, and a time-out are minimum requirements for preventing wrong-site errors.
  • The environment where major regional anesthesia procedures such as paravertebral blocks are performed is critical to patient safety.

Michael J. Barrington, MBBS, PhD Department of Anaesthesia and Acute Pain Medicine St. Vincent's Hospital, Melbourne Melbourne Medical School Faculty of Medicine, Dentistry and Health Sciences University of Melbourne Parkville, Victoria, Australia

Yoshiaki Uda, MBBS Department of Anesthesia Toronto General Hospital Toronto, Canada


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This project was funded under contract number 75Q80119C00004 from the Agency for Healthcare Research and Quality (AHRQ), U.S. Department of Health and Human Services. The authors are solely responsible for this report’s contents, findings, and conclusions, which do not necessarily represent the views of AHRQ. Readers should not interpret any statement in this report as an official position of AHRQ or of the U.S. Department of Health and Human Services. None of the authors has any affiliation or financial involvement that conflicts with the material presented in this report. View AHRQ Disclaimers
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