Comparison of Femoral Nerve Catheter, Adductor Canal Catheter, and Periarticular Liposomal Bupivacaine Infiltration for Postoperative Analgesia After Primary Total Knee Arthroplasty.

BACKGROUND: Peripheral nerve catheters are used to provide analgesia after total knee arthroplasty (TKA) and have been shown to decrease pain and opioid use, to facilitate participation with physical therapy (PT), and to hasten discharge. More recently, pericapsular infiltration using liposomal bupivacaine (LB) has been employed as an alternative analgesic approach. METHODS: This retrospective study compared outcomes for three analgesic approaches: femoral nerve catheter (FNC), adductor canal catheter (ACC), and intraoperative LB infiltration. The primary outcome was numeric rating scale (NRS) pain scores at 24 hours. Secondary outcomes included pain scores at 12, 36, and 48 hours, time-to-first opioid, cumulative opioid use, distance walked, and time-to-discharge. RESULTS: Pain scores at 24 hours were significantly lower in both the ACC and FNC cohorts when compared to the LB cohort (3.1 versus 4.6 [P = .017] and 2.4 versus 4.6 [P < .0001]). The ACC and FNC groups did not differ significantly at that timepoint (P = .27). Similar comparisons were found at 12 and 36 hours, while at 48 hours the FNC group was superior. Time to first opioid and opioid consumption favored the ACC and FNC groups. Walking distance favored the ACC group. Both the ACC and LB groups had a faster time-to-discharge than the FNC group. CONCLUSION: Both ACCs and FNCs provided superior analgesia at 24 hours compared to LB, while being equivalent to each other. Pain scores at 12 hours and 36 hours as well as opioid consumption through 48 hours mirrored this finding. Although various differences were found between groups in terms of time-to-first analgesic, walking distance and time-to-discharge, the ACC approach appeared to optimally balance analgesia, ambulation, and time-to-discharge.

Opioid abuse and perioperative care: a new medical disease.

PURPOSE OF REVIEW: This review article aims to describe the perioperative clinical implications of opioid use or opioid use disorder (OUD) and to provide recommendations related to analgesia, anesthesia, and postoperative care for patients with this 'new medical disease'. RECENT FINDINGS: Evidence suggest that 1 in 4 surgical patients will be using opioids preoperatively. Management of these patients, or those with OUD, can be challenging given their opioid tolerance, hyperalgesia, decreased pain tolerance, and increased pain sensitivity. Therefore, an individualized plan that considers how to manage OUD treatment medications, the risk of relapse, multimodal analgesia, and postoperative monitoring requirements is highly important. Fortunately, recent publications provide both insight and guidance on these topics. Postoperatively, persistent opioid utilization appears higher in patients currently using opioids and even for those with a prior history. Although numerous other adverse outcomes are also associated with opioid use or abuse, some may be modifiable with cessation. SUMMARY: A coordinated, evidence-based, multidisciplinary team approach is critical when caring for patients with OUD to ensure safety, provide adequate analgesia, and reduce the risk of relapse. Enhanced postoperative monitoring, multimodal analgesia, and a plan for preoperative opioid management may help to modify the risks of adverse postoperative outcomes.

Utility of the Pectoral Nerve Block (PECS II) for Analgesia Following Transaxillary First Rib Section.

BACKGROUND: The transaxillary approach to resection of the first rib is one of several operative techniques for treating thoracic outlet syndrome. Unfortunately, moderate to severe postoperative pain is anticipated for patients undergoing this particular operation. While opioids can be used for analgesia, they have well-described side effects that has led investigators to search for clinically relevant alternative analgesic modalities. We hypothesized that a regional analgesic procedure, commonly called a pectoral nerve (PECS II) block, which anesthetizes the second through sixth intercostal nerves as well as the long thoracic nerve and the medial and lateral pectoral nerves, would improve postoperative analgesia for patients undergoing a transaxillary first rib resection. METHODS: We performed a retrospective study by reviewing the charts of all patients that had undergone a transaxillary first rib resection for thoracic outlet syndrome during the defined study period. Patients that received a PECS II block were compared to those that did not. The primary outcome was a comparison of numeric rating scale pain scores during the first 24 hours following the operation. Secondary outcomes included cumulative opioid consumption during the same time period. RESULTS: Pain scores during the first 24 hours following the operation were not statistically different between groups (Block Group: 3.9 [2.1-5.3] [median (IQR 25-75%)] versus Non-block Group: 3.6 [2.4-4.1]; P = 0.40. In addition, opioid use through the first 24 hours after the operation was not significantly different (43.5 [22.0-81.0] [median morphine equivalents in mg's] versus 42.0 [12.5-75.0]; P = 0.53). CONCLUSIONS: An ultrasound-guided PECS II nerve block did not reduce postoperative pain scores or opioid consumption for patients undergoing a transaxillary first rib resection. However, a prospective, randomized, study with improved power would be beneficial to further explore the potential utility of a PECS II block for patients presenting for this surgical procedure.

Organizational Safety Climate and Job Enjoyment in Hospital Surgical Teams With and Without Crew Resource Management Training.

OBJECTIVE: The association between organizational safety climate (OSC) and job enjoyment (JE) for team members in surgical units in 2 hospitals was investigated. The treatment hospital received airline industry-based crew resource management (CRM) training, and the comparison hospital did not. BACKGROUND: Strong OSC has been positively associated with healthy hospital work environments and was expected to also be associated with employee job enjoyment. METHODS: Two hundred sixty-two surgical personnel responded to surveys about OSC and JE. RESULTS: The effects of OSC on JE did not depend on having CRM training. However, OSC and JE scores were higher in the treatment hospital, and the main effect of OSC and JE scores in the treatment hospital was highly significant (P < 0.001), with higher safety climate scores associated with higher JE. CONCLUSIONS: A strong OSC is important to employee job enjoyment. Nurse leaders should promote measures to strengthen the OSC in their surgical services departments.

Exploring the Association Between Organizational Safety Climate, Failure to Rescue, and Mortality in Inpatient Surgical Units.

OBJECTIVE: To examine the association between organizational safety climate (OSC), in-hospital mortality (IM), and failure to rescue (FTR) in 2 hospitals, 1 with and 1 without crew-resource-management training. BACKGROUND: OSC is 1 of the most important organizational factors that promotes safety at work; however, there is a lack of research examining the relationship between OSC and patient deaths in hospitals. METHODS: We utilized a matched 2-group comparison of surgical patients and surveyed surgical staff to assess the relationship between OSC, FTR, and IM. RESULTS: The OSC assessment was completed by 261 surgical team members. A total of 1764 patients had at least 1 FTR complication; however, there was no association between OSC with FTR or IM for either hospital. CONCLUSIONS: Nurse leaders should remain vigilant in building work teams with strong hospital safety climates. More research is needed to explore the relationship between OSC and patient outcomes.

Failure to rescue and 30-day in-hospital mortality in hospitals with and without crew-resource-management safety training.

Failure to rescue (FTR) occurs when a clinician is unable to save a hospitalized patient's life when they experience a complication that was not present on admission. Research suggests that a focus on patient safety, including implementing airline-industry-based-crew-resource management (CRM) training, can improve patient outcomes, however, the effects of CRM on FTR are unknown. This study examined FTR and 30-day in-hospital mortality (IM) outcomes in two hospitals to determine if differences existed in the treatment hospital (received CRM training) and the comparison hospital (did not receive CRM training). Researchers expected there would be lower rates of FTR and IM in the treatment hospital than the comparison hospital. The study utilized a matched two-group comparison, cross-sectional quasi-experimental design. Over 10,000 patients (n = 10,823) comprised the study with 1,764 having at least one FTR complication. Adjusted odds of FTR were 2.9% higher for treatment versus comparison but these results did not reach significance. The adjusted odds of IM were 0.4% higher for treatment versus comparison but not significantly higher. Although the reasons for our findings remain unclear, previous researchers also found that CRM training improved staff outcomes but unexpectedly did not improve patient outcomes. CRM training may best be used to target changes in staff behaviors and improvement in staff outcomes. Refresher CRM training may be needed to prevent drifting back into longstanding behaviors. Reductions in FTR and patients with IM outcomes may require more comprehensive, multipronged interventions in addition to CRM training.

Analgesic Benefit of Pectoral Nerve Block II Blockade for Open Subpectoral Biceps Tenodesis: A Randomized, Prospective, Double-Blinded, Controlled Trial.

BACKGROUND: Axillary pain is common after arthroscopic shoulder surgery with an open subpectoral biceps tenodesis. We hypothesized that adding a pectoral nerve block II (Pecs II) to an interscalene block (ISB) would improve postoperative analgesia in this surgical population. METHODS: Forty patients were enrolled in this prospective, randomized, observer and patient-blinded, single-institution trial. All 40 patients received a single-injection ISB with 20 mL of 0.25% bupivacaine with 1:400,000 epinephrine and 1:600,000 clonidine. The intervention arm (ISB + Pecs II) consisted of 20 patients who also received a Pecs II block using 30 mL of 0.25% bupivacaine with 1:400,000 epinephrine and 1:600,000 clonidine. The 20 control group patients (ISB) received a sham Pecs II block. The primary outcome was postoperative pain scores at 6 hours using the numeric rating scale (NRS; range, 0-10) and was analyzed using the Mann-Whitney U test. Secondary outcomes included the presence of axillary pain at 6 hours, the need for postanesthesia care unit (PACU) opioids, PACU length of stay (LOS) (minutes), NRS pain scores at 24 hours, cumulative opioid usage postdischarge through 24 hours, the presence of nausea or vomiting during the first 24 hours, and Pecs II block duration (in hours, based on time to onset of axillary pain). Data were analyzed using a modified intention-to-treat (ITT) methodology. RESULTS: Pain scores (NRS, 0-10) at 6 hours differed significantly between groups: ISB 3.0 (0.25-5.0) (1.7-4.3) versus ISB + Pecs II 0.0 (0-2.0) (0.0-1.1) (median [IQR] [95% CI]); P = .026. Hodges-Lehmann estimator of the difference was 2.0 (95% CI, 0.0-4.0). Fewer patients in the ISB + Pecs II group reported axillary pain at 6 hours and fewer required opioids in the PACU. There were no differences in any of the remaining secondary outcomes. CONCLUSIONS: The addition of a Pecs II block to an ISB for patients undergoing arthroscopic shoulder surgery with an open subpectoral biceps tenodesis significantly improved postoperative analgesia and reduced the need for opioids in the PACU.

Single-Injection Adductor Canal Block With Multiple Adjuvants Provides Equivalent Analgesia When Compared With Continuous Adductor Canal Blockade for Primary Total Knee Arthroplasty: A Double-Blinded, Randomized, Controlled, Equivalency Trial.

BACKGROUND: Peripheral nerve blockade is used to provide analgesia for patients undergoing total knee arthroplasty. This study compared a single-injection adductor canal block (SACB) with adjuvants to continuous adductor canal blockade (CACB). The hypothesis was that the 2 groups would have equivalent analgesia at 30 hours after neural blockade. METHODS: This was a double-blinded, randomized, controlled, equivalency trial. Sixty patients were randomized to either the SACB group (20 mL of 0.25% bupivacaine, 1.67 mcg/mL of clonidine, 2 mg of dexamethasone, 150 mcg of buprenorphine, and 2.5 mcg/mL of epinephrine) or the CACB group (20 mL 0.25% of bupivacaine injection with 2.5 mcg/mL of epinephrine followed by an 8 mL/h infusion of 0.125% bupivacaine continued through postoperative day 2). The primary outcome was movement pain scores at 30 hours using the numeric rating scale (NRS). The secondary outcomes included serial postoperative NRS pain scores (rest and movement every 6 hours), opioid consumption, time to first opioid administration, ability to straight leg raise, patient satisfaction, length of stay, and the incidence of nausea/vomiting. RESULTS: An intention-to-treat analysis included 59 patients. The NRS pain scores with movement were equivalent at 30 hours (SACB 5.5 ± 2.8 vs CACB 5.7 ± 2.9 [mean NRS ± standard deviation]; mean difference 0.2 [-1.5 to 1.0 {90% confidence interval}]). All NRS pain scores were equivalent until 42 hours (rest) and 48 hours (rest and movement) with the CACB group having lower pain scores. Other secondary outcomes were not statistically different. CONCLUSION: An SACB provides equivalent analgesia for up to 36 hours after block placement when compared with a CACB for patients undergoing total knee arthroplasty, though a CACB was favored at 42 hours and beyond.

An Evaluation of Ultrasound-Guided Adductor Canal Blockade for Postoperative Analgesia After Medial Unicondylar Knee Arthroplasty.

BACKGROUND: Unicondylar knee arthroplasty (UKA) is a commonly performed procedure with significant expected postoperative pain. Peripheral nerve blocks are 1 analgesic option, but some approaches may decrease quadriceps motor strength and interfere with early ambulation. In this study, we compared the analgesia provided by an adductor canal block (ACB) and a psoas compartment block (PCB) after UKA. We hypothesized that the ACB would provide equivalent analgesia, defined as a difference of <2 points on the pain scale (0-10 numeric rating scale [NRS]), at rest and with movement 6 hours after block placement. METHODS: One hundred fifty patients undergoing medial UKA were randomly assigned to receive either an ACB or a PCB with 0.25% bupivacaine, 5 µg/mL epinephrine, and 1.67 µg/mL clonidine. All patients received multimodal analgesics, sham blockade at the alternate site, and a posterior capsule injection during surgery. Patients and observers were blinded to treatment groups. The primary end points were NRS pain scores with rest and movement at 6 hours. Secondary end points included quadriceps muscle strength at 6 hours (0-5 [5 being full strength]; Medical Research Council scale) as well as NRS pain scores, opioid consumption, and opioid-related side effects over 24 hours. RESULTS: One hundred forty-seven patients were analyzed. Pain scores were equivalent at 6 hours with rest (ACB 1.0 ± 2 vs PCB 1.1 ± 2.2 [mean NRS ± SD]; 95% confidence interval of mean difference, -0.8 to 0.6; P < 0.0001) and with movement (ACB 1.6 ± 2.6 vs PCB 1.5 ± 2.8; 95% confidence interval of mean difference, -0.8 to 0.9; P < 0.0001). In addition, pain scores at rest and with movement at 12, 18, and 24 hours were equivalent. Quadriceps motor strength was significantly increased in the ACB group (Medical Research Council scale score, 4.0 ± 1.1 vs 2.5 ± 1.3 [mean ± SD]; P < 0.0001). No significant differences were found between groups for time to first analgesic or for cumulative opioid consumption at 6, 12, 18, or 24 hours. Other than an increase in the incidence of pruritus in the ACB group at 6 hours, there were no differences in opioid-related side effects. CONCLUSIONS: An ACB provides equivalent analgesia after medial UKA when compared with a PCB. In addition, the ACB caused significantly less motor weakness. An ACB should be considered for postoperative analgesia after medial UKA.

Evaluating residual anti-Xa levels following discontinuation of treatment-dose enoxaparin in patients presenting for elective surgery: a prospective observational trial.

INTRODUCTION: Prior studies have demonstrated that patients presenting for elective surgery may have higher-than-expected residual anti-Xa level activity at or beyond 24 hours following their last treatment dose of enoxaparin. Given that 24 hours of abstinence is currently recommended by both European and American societies before the performance of neuraxial or deep anesthetic/analgesic procedures, determining the actual timeframe at which residual anti-Xa level activity reliably falls below 0.2 IU/mL, the lower limit of the target range for thromboprophylaxis, is critical. METHODS: This was a prospective observational trial. Consenting patients on treatment-dose enoxaparin were randomized to either a 24-hour group (last dose at 07:00 the day prior to surgery) or a 36-hour group (last dose at 19:00 2 days prior to surgery). On arrival for surgery, blood samples were obtained to assess residual anti-Xa level activity and renal function. The primary outcome was residual anti-Xa level activity following the last treatment dose of enoxaparin. Incorporating all patients, linear regression modeling was performed to predict the timepoint at which the level of anti-Xa activity reliably fell below 0.2 IU/mL. RESULTS: 103 patients were analyzed. Time from the last dose at which residual anti-Xa activity fell below 0.2 IU/mL, based on the upper bound of the 95% CI, was 31.5 hours. No correlation overall between age, renal function, or sex was found. CONCLUSION: Residual levels of anti-Xa activity do not reliably fall below 0.2 IU/mL 24 hours following discontinuation of treatment-dose enoxaparin. Therefore, current time-based guidelines are not conservative enough. Routine anti-Xa testing should be strongly considered, or current time-based guidelines should be reassessed. TRIAL REGISTRATION NUMBER: NCT03296033.

Ultrasound-guided continuous superficial peroneal nerve block below the knee for the treatment of nerve injury.

(CRPS) describes a constellation of symptoms including pain, trophic changes, hyperesthesia, allodynia, and dysregulation of local blood flow often following trauma. It is often confined to the extremities. Treatment of this disorder consists of a variety of modalities including systemic pharmacotherapy, local anesthetic injections or infusions, psychological nonpharmacotherapy, physical rehabilitation, and surgical intervention. Chronic pain not related to CRPS can also be treated with similar interventions. Despite the array of available therapies, it can still be difficult to manage. We report a case of a 19-year-old patient diagnosed by her surgeon as having CRPS Type II, secondary to foot trauma, which was treated with a continuous infusion of local anesthetic at the superficial peroneal nerve (SPN). While placement of peripheral nerve block catheters to augment chronic pain therapy is not novel, the application of a perineural catheter at the SPN has not been previously described.

Hypotension duration and vasopressor requirements following intrathecal oxytocin for Total hip arthroplasty: Secondary analysis of a randomized controlled trial.

INTRODUCTION: A recent publication investigating intrathecal oxytocin, 100 µg, administered immediately prior to a spinal anesthetic in patients undergoing primary total hip arthroplasty surgery demonstrated a reduction in disability for 3-weeks, increased walking distance at 8-weeks, and earlier opioid cessation. This secondary analysis study was undertaken to assess the acute cardiovascular safety and analgesic efficacy of intrathecal oxytocin in this study population. METHODS: 90 patients were included in the analysis (44 randomized to spinal oxytocin and 46 to placebo [saline]). Data collected prospectively during the previously published study were supplemented with additional retrospectively collected data. The primary outcomes were comparisons of the duration of hypotension (minutes with mean arterial pressure < 65 mmHg) and cumulative vasopressor requirements during the initial 60 min following spinal placement. Secondary outcomes included hypotension durations and vasopressor requirements at later time points, perioperative fluid administration, physical therapy metrics, time to first opioid administration, cumulative opioid consumption through 24 h, and verbal pain scores through 24 h. RESULTS: The duration of hypotension during the first 60 min following spinal placement did not differ between intrathecal oxytocin and placebo groups (12.2 ± 10.7 vs 14.0 ± 13.0 min, respectively; p = 0.476). There was also no difference in cumulative vasopressor requirements (1303 ± 883 vs 1156 ± 818 µg [phenylephrine equivalents]; p = 0.413) during that time period. No group differences were found for any of the investigated secondary outcomes. CONCLUSION: The administration of 100 µg of intrathecal oxytocin does not significantly impact the duration of hypotension or the need for vasopressor agents when given as a component of a spinal anesthetic. The oxytocin and placebo groups also did not differ in regards to physical therapy related metrics, time to first opioid administration, cumulative opioids at 24-h, or pain scores through 24-h. What is already known on this topic: Rapid intravenous oxytocin causes hypotension after cesarean delivery, but intrathecal oxytocin does not cause hypotension in healthy volunteers. WHAT THIS STUDY ADDS: Compared to saline control, intrathecal oxytocin, 100 µg did not increase the duration of hypotension or vasopressor requirements in patients during total hip arthroplasty. How this study might affect research, practice, or policy: Lack of hypotension from intrathecal oxytocin in this study supports future investigations to further explore its potential benefits, in terms of both analgesia and functional recovery following surgery.

Randomized controlled trial of intrathecal oxytocin on speed of recovery after hip arthroplasty.

ABSTRACT: Recovery from surgery is quicker in the postpartum period, and this may reflect oxytocin action in the spinal cord. We hypothesized that intrathecal injection of oxytocin would speed recovery from pain and disability after major surgery. Ninety-eight individuals undergoing elective total hip arthroplasty were randomized to receive either intrathecal oxytocin (100 µg) or saline. Participants completed diaries assessing pain and opioid use daily and disability weekly, and they wore an accelerometer beginning 2 weeks before surgery until 8 weeks after. Groups were compared using modelled, adjusted trajectories of these measures. The study was stopped early due to the lack of funding. Ninety patients received intrathecal oxytocin (n = 44) or saline (n = 46) and were included in the analysis. There were no study drug-related adverse effects. Modelled pain trajectory, the primary analysis, did not differ between the groups, either in pain on day of hospital discharge (intercept: -0.1 [95% CI: -0.8 to 0.6], P = 0.746) or in reductions over time (slope: 0.1 pain units per log of time [95% CI: 0-0.2], P = 0.057). In planned secondary analyses, postoperative opioid use ended earlier in the oxytocin group and oxytocin-treated patients walked nearly 1000 more steps daily at 8 weeks ( P < 0.001) and exhibited a clinically meaningful reduction in disability for the first 21 postoperative days ( P = 0.007) compared with saline placebo. Intrathecal oxytocin before hip replacement surgery does not speed recovery from worst daily pain. Secondary analyses suggest that further study of intrathecal oxytocin to speed functional recovery without worsening pain after surgery is warranted.

Surface Landmarks in the Lateral Decubitus Position Are Unreliable for Thoracic Epidural Catheter Placement: A Case Series.

Thoracic epidurals remain the optimal method for providing postoperative analgesia after complex open abdominal and thoracic surgeries. However, they can be challenging to both place and maintain, as evidenced by a failure rate that exceeds 30%.1 Proper identification of the epidural space and accurate placement of the catheter are critical in order to deliver effective postoperative analgesia and avoid failure.2,3 This case series investigated the difficulty in correctly identifying the proper vertebral level for thoracic epidural catheter procedures when performed in the lateral decubitus position.

Hypokalemic Periodic Paralysis Masquerading as a Compressive Neuraxial Lesion Following Lumbar Epidural Placement in a Parturient: A Case Report.

We report the management of a parturient with undiagnosed hypokalemic periodic paralysis (HOKPP) who underwent epidural analgesia for labor, complicated by an unintentional dural puncture, and the eventual use of epidural anesthesia for cesarean delivery. Following discharge, she represented with lower extremity paresis. After being evaluated for a compressive neuraxial lesion, she made a full recovery following potassium repletion. The obstetric anesthetic implications for patients with HOKPP and how this disorder impacts the evaluation of acute motor weakness in the immediate postpartum period in a patient who recently received a neuraxial procedure are discussed.

Ilioinguinal/Iliohypogastric versus quadratus lumborum nerve blockade for elective open inguinal herniorrhaphy: a prospective, randomized, double-blinded, equivalency trial.

BACKGROUND: Open inguinal herniorrhaphy (OIH) is a commonly performed surgical procedure with expected postoperative pain. Historically, an option for regional analgesia has been an ilioinguinal and iliohypogastric nerve block (IINB). More recently, the transmuscular quadratus lumborum block (QLB) has been used as an analgesic technique for a variety of abdominal and truncal surgical procedures. Given our own institutional experiences with the performance of QLB combined with the body of literature supporting the proximal blockade of the ilioinguinal and iliohypogastric nerves via this approach, we compared the analgesia provided by an IINB to a QLB. We hypothesized that the two blocks would provide equivalent analgesia, as defined by a difference of less than±2 points on the pain scale (0-10 numeric rating scale (NRS)), for patients undergoing OIH. METHODS: Sixty patients scheduled for elective outpatient OIH under general anesthesia were randomized to preoperatively receive either an IINB or a transmuscular QLB with 0.25% bupivacaine/epinephrine/clonidine for postoperative analgesia. The primary endpoint was movement NRS pain scores at 8 hours. Secondary outcomes included resting NRS pain scores at 8 and 24 hours, movement NRS pain scores at 24 hours, incidence of opioid related side effects (nausea, vomiting, pruritus), time-to-first oral opioid analgesic, and total opioid consumption at 24 hours. RESULTS: Fifty-nine patients were analyzed per an intention-to-treat approach (one patient was excluded because the surgical procedure was canceled). Movement pain scores at 8 hours were equivalent (IINB 5.10±3.02 vs QLB 5.03±3.01 (mean NRS±SD); two one-sided test mean difference (90% CI), 0.07 (-1.24 to 1.38), p ≤0.01). There were no differences between groups for any of the secondary endpoints. CONCLUSION: An IINB and a transmuscular QLB are equivalent with regards to their ability to provide postoperative analgesia after OIH.

Preprocedural checklist for regional anesthesia: impact on the incidence of wrong site nerve blockade (an 8-year perspective).

BACKGROUND: The term "Wrong-Site Surgery (WSS)" is commonly associated with surgical procedures; however, The Joint Commission (TJC) considers any invasive procedure, not just a surgical procedure, performed on the wrong side, at the wrong site, or on the wrong patient to be a WSS. For anesthesia providers, this means that a wrong-site nerve block (WSNB) also constitutes a WSS and would be considered a sentinel event by TJC. In an attempt to combat WSNB, the American Society of Regional Anesthesia and Pain Medicine published guidelines in 2014 recommending the use of a preprocedural checklist before performing regional blocks. The effectiveness of such a checklist, however, to reduce the occurrence of WSNB has not yet been demonstrated. We hypothesized that the introduction of a preprocedural checklist specific for regional anesthesia would be associated with a lower rate of WSNB procedures. METHODS: A retrospective review was performed to compare the incidence of WSNB 2 years before, to 6 years after the implementation of a preprocedural checklist specific to regional anesthesia. RESULTS: Prior to checklist implementation, 4 WSNB events occurred during 10 123 procedures (3.95 per 10 000 (95% CI 1.26 to 9.53). Following implementation, WSNB events occurred during 35 890 procedures (0 per 10 000 (95% CI 0 to 0.84)); p=0.0023. CONCLUSIONS: Implementation of a regional anesthesia specific preprocedural checklist was associated with a significantly lower incidence of WSNB procedures. While prospective controlled studies would be required to demonstrate causation, this study suggests that for regional anesthesia procedures, a preprocedural checklist may positively impact patient safety.