Acute and nonacute complications associated with interscalene block and shoulder surgery: a prospective study

Current Strategies in Regional Anesthesia for Shoulder Surgery

As arthroscopic and open shoulder surgery is increasingly performed on an outpatient basis, optimal and prolonged pain control is becoming more important while minimizing associated adverse effects. Traditional analgesic strategies relying on opioid and nonopioid medications provide inadequate pain control and are associated with undesirable adverse effects, such as opioid-related adverse effects (postoperative nausea and vomiting, respiratory depression, sedation), gastric lining irritation, and renal and hepatic adverse effects. Advances in ultrasonography-guided regional anesthesia have made placement of interscalene brachial plexus nerve blocks more reliable and precise and aided development of novel phrenic nerve-sparing peripheral nerve block techniques that decrease the risk of diaphragmatic paresis and dyspnea. Using a brachial plexus block combined with multimodal medications is the preferred method to provide comprehensive analgesia to target multiple pain pathways for additive or synergistic pain control effects in the perioperative period while minimizing opioid medication usage. An understanding of current anesthetic and analgesic strategies can lead to an improved pain management pathway and outcomes in patients undergoing shoulder surgery.

Toxic effects of local anesthetics on rat fibroblasts: An in-vitro study

BACKGROUND

Infusion catheters facilitate a controlled infusion of local anesthetic (LA) for pain control after surgery. However, their potential effects on healing fibroblasts are unspecified.

METHODS

Rat synovial fibroblasts were cultured in 12-well plates. Dilutions were prepared in a solution containing reduced-serum media and 0.9% sodium chloride in 1:1 concentration. Each well was treated with 500 μl of the appropriate LA dilution or normal saline for 15- or 30-min. LA dilutions included: 0.5% ropivacaine HCl, 0.2% ropivacaine HCl, 1% lidocaine HCl and epinephrine 1:100,000, 1% lidocaine HCl, 0.5% bupivacaine HCl and epinephrine 1:200,000, and 0.5% bupivacaine HCl. This was replicated three times. Dilution of each LA whereby 50% of the cells were unviable (Lethal dose 50 [LD50]) was analyzed.

RESULTS

LD50 was reached for lidocaine and bupivacaine, but not ropivacaine. Lidocaine 1% with epinephrine is toxic at 30-min at 1/4 and 1/2 sample dilutions. Bupivacaine 0.5% was found to be toxic at 30-min at 1/2 sample dilution. Bupivacaine 0.5% with epinephrine was found to be toxic at 15- and 30-min at 1/4 sample dilution. Lidocaine 1% was found to be toxic at 15- and 30-min at 1/2 sample dilution. Ropivacaine 0.2% and 0.5% remained below LD50 at all time-points and concentrations, with 0.2% demonstrating the least cell death.

CONCLUSIONS

Though pain pumps are generally efficacious, LAs may inhibit fibroblasts, including perineural fibroblast and endoneurial fibroblast-like cells, which may contribute to persistent nerve deficits, delayed neurogenic pain, and negatively impact healing. Should a continuous infusion be used, our data supports ropivacaine 0.2%.

LEVEL OF EVIDENCE

Basic Science Study; Animal model.

Delayed Presentation of Horner's and Harlequin-Like Symptoms Following Interscalene Peripheral Nerve Catheter Placement

Interscalene peripheral nerve catheters are a commonly performed procedure often used to provide continuous outpatient analgesia following orthopedic procedures. In this case report, we present an interesting case of a patient who received an interscalene catheter following an orthopedic procedure and demonstrated an atypical presentation of combined partial Horner's and Harlequin-like syndromes evolving more than 36 hours after block placement. Although several case reports in the literature exist describing incidents in which interscalene catheter migration has led to the late onset of complications, it has never before been observed with either this degree of delay or this combination of symptoms. This case emphasizes the importance of recognizing irregular presentations of interscalene block complications secondary to catheter migration.

Simulation in Regional Anaesthesia: A Narrative Review of Its History, Evolution and Future Prospects

Regional anaesthesia has seen a resurgence of sorts since the widespread advent of ultrasound into clinical practice. The ability to access hitherto inaccessible nerves and fascial planes in the human body whilst ensuring visualisation of the needle tip during block performance has opened the proverbial floodgates leading to its widespread adoption, further supported by a growing body of evidence for its many benefits in a patient's perioperative journey and pain management. The concomitant advancement of technology and the development of powerful simulation and artificial intelligence tools has given a much-needed impetus towards improving training and safe practice in regional anaesthesia. Methods: We performed a detailed search of databases, including PubMed Medline, Web of Science, EBSCO, Embase and the Cochrane Library, up to October 2024. Our search was conducted using phrases including (but not limited to) "history of anaesthesia", "history of simulation", "regional anaesthesia and simulation", AI and "artificial intelligence and anaesthesia".

The incidence and decompression rates of median and ulnar neuropathies following shoulder surgery

Background

Upper extremity peripheral neuropathy is a known, but uncommon complication that can occur after shoulder surgery. The incidence rate is well documented, and most of these cases historically have been treated conservatively. However, we hypothesize peripheral compression neuropathy requires a much higher need for surgical decompression than originally reported. The purpose of this study was to evaluate the incidence, decompression rates, and prognostic factors for developing median and ulnar neuropathies following shoulder surgery.

Methods

A retrospective chart review was performed examining patients who underwent open and arthroscopic shoulder surgery from a multisurgeon, single-institution database. Perioperative data and functional outcomes were recorded. Symptom resolution was assessed with both conservative and surgical management of compression peripheral neuropathy. Further analysis was made to compare open and arthroscopic procedures, the type of neuropathy developed, and electromyographic (EMG) severity.

Results

The incidence rates of compression peripheral neuropathy following open arthroplasty and arthroscopic procedures was 1.80% (31/1722) and 0.54% (44/8150), respectively. 73.33% (55/75) of patients developed ipsilateral disease, while 20.00% (15/75) of patients had bilateral disease. Amongst the 75 included patients, there were 99 cases of neuropathy. Carpal tunnel syndrome was more common than cubital tunnel syndrome, comprising 61.61% (61/99) cases of neuropathy. 12.00% (9/75) of patients developed both carpal tunnel syndrome and cubital tunnel syndrome. Four patients were lost to follow-up. Decompression surgery was performed for 36.84% (35/95) cases of neuropathy with >90% obtaining symptom resolution with surgery. 63.16% (60/95) cases of neuropathy were managed conservatively, 71.67% (43/60) of which had persistent symptoms. When comparing arthroscopic versus open procedures, patients who underwent open procedures were significantly older (68.62 vs. 49.78 years, P < .001) and developed peripheral neuropathy significantly faster after the index procedure (87.24 vs. 125.58 days, P = .008). EMG severity did not correlate with decompression rates or symptom resolution. There were no differences in the subgroup analyses between beach chair and lateral positioning in regard to the type of neuropathy, laterality of symptoms, and/or treatment received.

Conclusion

The overall incidence of peripheral neuropathy after shoulder surgery was 0.76% (75/9872). The development of peripheral neuropathy is multifactorial, with older patients undergoing open arthroplasty more at risk. Neuropathy symptoms were refractory to conservative management despite the type of shoulder surgery, type of neuropathy, or EMG severity. Decompression consistently led to resolution of symptoms.

A comparison of the continuous supraclavicular brachial plexus block using the proximal longitudinal oblique approach and the interscalene brachial plexus block for arthroscopic shoulder surgery: A randomised, controlled, double-blind trial

BACKGROUND

Continuous interscalene brachial plexus block (ISB) is widely used for arthroscopic shoulder surgery, but the incidence of hemidiaphragmatic paresis (HDP) has been reported to reach 100%. Several methods, including injections distal to the C5-C6 nerve roots, have been attempted to reduce the HDP incidence. However, catheter placement distal to the C5-C6 nerve roots interferes with the surgical site.

OBJECTIVE

Our primary objective was to describe a new technique, the supraclavicular brachial plexus block (SCB), using the proximal longitudinal oblique approach (PLO-SCB), which can facilitate catheter placement and, when compared with ISB, to test whether this would provide noninferior analgesia and spare the phrenic nerve.

DESIGN

Prospective, randomised, double-blind study.

SETTING

Operating rooms, postanaesthesia care unit, and wards.

PATIENTS

Seventy-six patients aged 20 to 80 years scheduled for arthroscopic shoulder surgery.

INTERVENTIONS

Patients were randomly assigned to the continuous PLO-SCB ( n  = 40) or the continuous ISB ( n  = 40) groups. All patients received an initial low-volume single-injection (5 ml 0.75% ropivacaine) followed by a patient-controlled infusion of 0.15% ropivacaine.

MAIN OUTCOME MEASURES

The primary outcomes were the incidence of HDP and pain scores. Secondary outcomes were respiratory function, postoperative analgesic consumption, sensory and motor function, and complications.

RESULTS

The HDP incidence was significantly lower in the PLO-SCB group than in the ISB group at 30 min after block injection: 0% (0 of 38 patients) and 73.7% (28 of 38 patients), respectively ( P  < 0.001). Similarly, at 24 h after surgery, the incidences were 23.7% (9 of 38 patients) and 47.4% (18 of 38 patients) in the PLO-SCB and ISB groups, respectively ( P  = 0.002). Median [IQR] NRS pain scores at rest measured after surgery in the ISB and PLO-SCB groups were similar: immediately after surgery, 1 [0 to 2] vs. 1 [0 to 1], P  = 0.06); at 30 min, 2 [0.25 to 2] vs. 1 [0 to 2], P  = 0.065); and at 24 h 2 [0.25 to 3] vs. 1 [0 to 3], P  = 0.47, respectively.

CONCLUSION

For major shoulder surgery, compared with continuous ISB, continuous PLO-SCB was more sparing of diaphragmatic and respiratory function while providing noninferior analgesia. Catheter placement via the PLO approach is feasible without interfering with the surgical field.

TRIAL REGISTRATION

Registered by the Clinical Trial Registry of Korea (Seoul, Korea; KCT0004759, http: cris.nih.go.kr, principal investigator: Hyungtae Kim).

Continuous Catheter Techniques

Continuous peripheral nerve block catheters are simple in concept: percutaneously inserting a catheter adjacent to a peripheral nerve. This procedure is followed by local anesthetic infusion via the catheter that can be titrated to effect for extended anesthesia or analgesia in the perioperative period. The reported benefits of peripheral nerve catheters used in the surgical population include improved pain scores, decreased narcotic use, decreased nausea/vomiting, decreased pruritus, decreased sedation, improved sleep, and improved patient satisfaction.

Post-COVID-19 patients suffer from chemosensory, trigeminal, and salivary dysfunctions

Recent literature indicates that post-COVID-19 patients suffer from a plethora of complications, including chemosensory dysfunction. However, little attention has been given to understand the interactions between chemosensory, trigeminal, and salivary dysfunctions in these patients. The aims of this study were (1) to investigate the prevalence and combinations of chemosensory, trigeminal, and salivary dysfunctions, (2) to identify the odorants/tastants that are compromised, and (3) to explore possible associations between the four dysfunctions in post-COVID-19 patients. One hundred post-COVID-19 patients and 76 healthy controls (pre-COVID-19) were included in this cross-sectional, case-controlled study. Participants' smell, taste, trigeminal, and salivary functions were assessed. The patients had a significantly higher prevalence of parosmia (80.0%), hyposmia (42.0%), anosmia (53.0%), dysgeusia (34.0%), complete ageusia (3.0%), specific ageusia (27.0%), dysesthesia (11.0%) and dry mouth (18.0%) compared to controls (0.0% for all parameters, except 27.6% for hyposmia). Complete loss of bitter taste was the most prevalent specific ageusia (66.7%) and coffee was the most common distorted smell (56.4%). Seven different combinations of dysfunction were observed in the patients, the most common being a combination of olfactory and gustatory dysfunction (48.0%). These findings indicate that post-COVID-19 patients experience a range of chemosensory, trigeminal, and salivary disturbances, occurring in various combinations.

Neurological injury following peripheral nerve blocks: a narrative review of estimates of risks and the influence of ultrasound guidance

BACKGROUND

Peripheral nerve injury or post-block neurological dysfunction (PBND) are uncommon but a recognized complications of peripheral nerve blocks (PNB). A broad range of its incidence is noted in the literature and hence a critical appraisal of its occurrence is needed.

OBJECTIVE

In this review, we wanted to know the pooled estimates of PBND and further, determine its pooled estimates following various PNB over time. Additionally, we also sought to estimate the incidence of PBND with or without US guidance.

EVIDENCE REVIEW

A literature search was conducted in six databases. For the purposes of the review, we defined PBND as any new-onset sensorimotor disturbances in the distribution of the performed PNB either attributable to the PNB (when reported) or reported in the context of the PNB (when association with a PNB was not mentioned). Both prospective and retrospective studies which provided incidence of PBND at timepoints of interest (>48 hours to <2 weeks; >2 weeks to 6 weeks, 7 weeks to 5 months, 6 months to 1 year and >1 year durations) were included for review. Incidence data were used to provide pooled estimates (with 95% CI) of PBND at these time periods. Similar estimates were obtained to know the incidence of PBND with or without the use of US guidance. Additionally, PBND associated with individual PNB were obtained in a similar fashion with upper and lower limb PNB classified based on the anatomical location of needle insertion.

FINDINGS

The overall incidence of PBND decreased with time, with the incidence being approximately 1% at <2 weeks' time (Incidence per thousand (95% CI)= 9 (8; to 11)) to approximately 3/10 000 at 1 year (Incidence per thousand (95% CI)= 0. 3 (0.1; to 0.5)). Incidence of PBND differed for individual PNB with the highest incidence noted for interscalene block.

CONCLUSIONS

Our review adds information to existing literature that the neurological complications are rarer but seem to display a higher incidence for some blocks more than others. Use of US guidance may be associated with a lower incidence of PBND especially in those PNBs reporting a higher pooled estimates. Future studies need to standardize the reporting of PBND at various timepoints and its association to PNB.

Shedding Light on Perioperative Nerve Injury: An Investigation Using the SHED (Symptoms Categorization-History Taking-Examination-Diagnostic Evaluations) Approach

Peripheral nerve blocks (PNBs) provide analgesia and anesthesia in diverse surgical procedures. Despite their recognized benefits, the occurrence of complications, particularly peripheral nerve injuries (PNIs), is a noteworthy concern. Prompt identification and intervention for perioperative nerve injuries are crucial to prevent permanent neurological impairment. A meticulous, systematic evaluation centered on the onset and progression of symptoms becomes imperative. The SHED (symptoms categorization-history taking-examination-diagnostic evaluations) approach serves as a valuable tool for diagnosing causative factors, determining the type of nerve injury, and formulating an effective treatment plan to mitigate further harm. This case report employs the SHED approach to elucidate a perplexing instance of PNIs. The patient, experiencing neurological symptoms post-forearm surgery under a PNB, serves as a focal point. The report underscores the significance of a systematic, stepwise approach in managing patients with suspected PNIs. Vigilant patient monitoring, collaborative teamwork, shared responsibilities, and consideration of potential contributing factors beyond the nerve block are highlighted for an accurate diagnosis and effective treatment of PNIs. The aim is to guide healthcare professionals in navigating similar clinical scenarios, ultimately ensuring patient safety and optimizing outcomes.

Pain Control for Sickle Cell Crisis, a Novel Approach? A Retrospective Study

Background and Objectives: Pain management poses a significant challenge for patients experiencing vaso-occlusive crisis (VOC) in sickle cell disease (SCD). While opioid therapy is highly effective, its efficacy can be impeded by undesirable side effects. Local regional anesthesia (LRA), involving the deposition of a perineural anesthetic, provides a nociceptive blockade, local vasodilation and reduces the inflammatory response. However, the effectiveness of this therapeutic approach for VOC in SCD patients has been rarely reported up to now. The objective of this study was to assess the effectiveness of a single-shot local regional anesthesia (LRA) in reducing pain and consequently enhancing the management of severe vaso-occlusive crisis (VOC) in adults with sickle cell disease (SCD) unresponsive to conventional analgesic therapy. Materials and Methods: We first collected consecutive episodes of VOC in critical care (ICU and emergency room) for six months in 2022 in a French University hospital with a large population of sickle cell patients in the West Indies population. We also performed a systematic review of the use of LRA in SCD. The primary outcome was defined using a numeric pain score (NPS) and/or percentage of change in opioid use. Results: We enrolled nine SCD adults (28 years old, 4 females) for ten episodes of VOC in whom LRA was used for pain management. Opioid reduction within the first 24 h post block was -75% (50 to 96%). Similarly, the NPS decreased from 9/10 pre-block to 0-1/10 post-block. Five studies, including one case series with three patients and four case reports, employed peripheral nerve blocks for regional anesthesia. In general, local regional anesthesia (LRA) exhibited a reduction in pain and symptoms, along with a decrease in opioid consumption post-procedure. Conclusions: LRA improves pain scores, reduces opioid consumption in SCD patients with refractory pain, and may mitigate opioid-related side effects while facilitating the transition to oral analgesics. Furthermore, LRA is a safe and effective procedure.

Postoperative neurological symptoms following arthroscopic shoulder surgery with interscalene block: an exploratory secondary analysis of pooled randomized controlled trial data

OBJECTIVE

Postoperative neurological symptoms (PONS) are recognized complications of regional anesthesia and orthopedic surgery. We aimed to better characterize prevalence and potential risk factors in a homogeneous population of randomized, controlled trial participants.

METHODS

Data were pooled from two randomized controlled trials of analgesia after interscalene block with perineural or intravenous adjuvants (NCT02426736, NCT03270033). Participants were at least 18 years of age and undergoing arthroscopic shoulder surgery at a single ambulatory surgical center. PONS were assessed by telephone follow-up at 14 days and 6 months postoperatively, and defined as patient report of numbness, weakness, or tingling in the surgical limb, alone or in combination, and regardless of severity or etiology.

RESULTS

At 14 days, PONS occurred in 83 of 477 patients (17.4%). Among these 83 patients, 10 (12.0%) continued to have symptoms a half-year after surgery. In exploratory univariate analyses, no patient, surgical or anesthetic characteristics were significantly associated with 14-day PONS except for lower postoperative day 1 Quality of Recovery-15 questionnaire total score (OR 0.97 (95% CI, 0.96 to 0.99), p<0.01). This result was driven largely by the emotional domain question scores (OR 0.90 95% CI 0.85 to 0.96, p<0.001). Report of all three of numbness, weakness and tingling at 14 days vs other 14-day symptom combinations was associated with persistent PONS at 6 months (OR 11.5 95% CI 2.2 to 61.8, p<0.01).

CONCLUSION

PONS are common after arthroscopic shoulder surgery performed with single injection ultrasound-guided interscalene blocks. No definitive mitigating risk factors were identified.

Surgeon-administered intraoperative brachial plexus block for open shoulder surgery - a novel and safe technique

In the era of outpatient shoulder surgery, bundled payment, safe, predictable, and time-efficient pain management strategies for shoulder arthroplasty (SA) are important. Ultrasound-guided interscalene blocks (ISBs), currently the gold standard for postoperative pain management after shoulder surgery, can be highly operator dependent, time-consuming, and not without complications. We developed a new surgical technique of surgeon-administered intraoperative brachial plexus block in patients undergoing SA open shoulder surgery using the deltopectoral approach. This procedure could be performed after the exposure, either at the beginning or end of the bony work. This procedure is simple, safe, and effective. We did not notice any complications that are typically seen with ISB-like respiratory depression secondary to phrenic nerve palsy, rebound pain after the block wore off, and pain related conversion of outpatient SA to inpatient, over the period of four years (2018-2022). This technique has additional advantages over the established "gold standard" ISB in terms of time and cost savings and improved operating room efficiency.

Neuropathies Following an Ultrasound-Guided Axillary Brachial Plexus Block

Purpose

Ultrasound-guided brachial plexus block (UGBPB) has interscalene, supraclavicular, infraclavicular, and axillary approaches. The axillary block is considered to be the safest and with fewer adverse events compared to the interscalene (eg, phrenic nerve block, spinal cord or vertebral artery puncture) and supraclavicular (eg, pneumothorax). However, with regard to postoperative neurological symptoms (PONS), it is controversial whether its incidence after an axillary block was higher than that after non-axillary approaches". In this study, we investigated whether the incidence of a neuropathy after an axillary block was higher than that after non-axillary approaches.

Patients and Methods

This was a single-center, retrospective cohort study. All UGBPBs were performed under general anesthesia between January 2014 and March 2020. The outcomes included the overall incidence of PONS and neuropathies for axillary and non-axillary approaches. The etiology, symptoms, and outcomes of patients were investigated.

Results

Of the 992 patients, 143 (14%) and 849 (86%) were subjected to axillary and non-axillary approaches, respectively. Among 19 cases (19.2:1000; 95% confidence interval [CI], 18.2-20.1) of PONS, four (4.0:1000; 95% CI, 3.8-4.2) were neuropathies attributed to the UGBPB, three (21.0:1000; 95% CI, 18.1-23.8) to the axillary and one (2.8:1000; 95% CI, 2.6-3.1) to non-axillary approaches. The incidence of neuropathies after an axillary block was significantly higher than that after non-axillary approaches (P = 0.005).

Conclusion

The incidence of neuropathies after US-guided axillary block under general anesthesia was significantly higher than that after non-axillary approaches.

Brachial plexus deficits in patients undergoing shoulder arthroplasty

Background

Nerve deficit following shoulder arthroplasty can cause significant morbidity. We examined the incidence and pattern of nerve injury following shoulder arthroplasty in a University Hospital.

Methods

Retrospective review of all patients undergoing shoulder arthroplasty over a five-year period (September 2014 to August 2019). Patients were identified using clinical codes and relevant data extracted by review of patient records. We excluded patients with preoperative nerve injuries.

Results

220 arthroplasties were performed in 210 patients. The overall nerve deficit rate was 2.3% (5/220). Five nerve deficits occurred following reverse total shoulder arthroplasty (rTSA). In two patients, nerve recovery occurred within 12 months. Two patients had persistent deficits at 12 months. One patient had a deficit at seven months, but incomplete follow up. There was no clear documentation of discussions with clinicians specialising in nerve injury.

Conclusion

Nerve injury rates in our series for rTSA are low and comparable to systematic review data. We purport that for rTSA, adequate soft tissue releases, careful arm positioning and retraction alongside limiting over-lowering the centre of rotation may prevent nerve injuries. A postoperative nerve deficit should warrant an opinion from a specialist in nerve surgery with clear referral pathways to allow efficient access to services.

The Incidence of Carpal Tunnel Syndrome Diagnosis Increases after Arthroscopic Shoulder Surgery

Purpose

Arthroscopic shoulder surgery has been identified as a potential risk factor for carpal tunnel syndrome (CTS). The purposes of this study were as follows: to (1) examine the percentage of patients who underwent arthroscopic shoulder procedures and later developed ipsilateral CTS within 1 year of the procedure, (2) determine the percentage of those patients with CTS who subsequently underwent an injection or release, and (3) examine comorbidities associated with developing CTS after surgery.

Methods

Patients who underwent arthroscopic rotator cuff repair (RCR), labral repair, or biceps tenodesis were retrospectively identified in a national database. Within 1 year, we compared the rates of ipsilateral CTS diagnoses versus the contralateral side. The rates of comorbidities between those who did and did not develop CTS were also compared.

Results

Within 1 year, arthroscopic RCR patients (1.47% vs 1.00%; odds ratio [OR], 1.48; P < .001) and arthroscopic labral repair patients (0.76% vs 0.52%; OR, 1.47; P < .001) had a significantly higher rate of ipsilateral carpal tunnel diagnosis versus contralateral side diagnosis. Arthroscopic RCR patients were also significantly more likely to have ipsilateral carpal tunnel injection (0.16% vs 0.11%; OR, 1.45; P < .001) and release (0.46% vs 0.37%; OR, 1.24; P < .001). Patients who had an ipsilateral carpal tunnel diagnosis following arthroscopic RCR and labral repair were both significantly older (both P < .001), a higher percentage of women (both P<.001), and more likely to have had a preoperative nerve block (both P < .05). Both cohorts had significantly higher mean Elixhauser comorbidity Index (P < .001) and more comorbidities.

Conclusions

This study demonstrated a significantly higher incidence of operative side CTS within 1 year following arthroscopic RCR and labral repairs. Arthroscopic RCR was also demonstrated to result in significantly higher rates of injections and carpal tunnel release. The cohort that developed ipsilateral CTS was older, had higher percentage of women, and had more comorbidities.

Type of study/level of evidence

Prognostic III.

"Knowing It Before Blocking It," the ABCD of the Peripheral Nerves: Part B (Nerve Injury Types, Mechanisms, and Pathogenesis)

Selander emphatically said, "Handle these nerves with care," and those words still echo, conveying a loud and clear message that, however rare, peripheral nerve injury (PNI) remains a perturbing possibility that cannot be ignored. The unprecedented nerve injuries associated with peripheral nerve blocks (PNBs) can be most tormenting for the unfortunate patient and a nightmare for the anesthetist. Possible justifications for the seemingly infrequent occurrences of PNB-related PNIs include a lack of documentation/reporting, improper aftercare, or associated legal implications. Although they make up only a small portion of medicolegal claims, they are sometimes difficult to defend. The most common allegations are attributed to insufficient informed consent; preventable damage to a nerve(s); delay in diagnosis, referral, or treatment; misdiagnosis, and inappropriate treatment and follow-up care. Also, sufficient prospective studies or randomized trials have not been conducted, as exploring such nerve injuries (PNB-related) in living patients or volunteers may be impractical or unethical. Understanding the pathophysiology of various types of nerve injury is vital to dealing with them further. Processes like degeneration, regeneration, remyelination, and reinnervation can influence the findings of electrophysiological studies. Events occurring in such a process and their impact during the assessment determine the prognosis and the need for further interventions. This educational review describes various types of PNB-related nerve injuries and their associated pathophysiology.

"Knowing It Before Blocking It," the ABCD of the Peripheral Nerves: Part D (Approach to the Patient With Nerve Injuries)

"Prevention is always better than cure." However, despite all precautions or preventive measures, sometimes patients develop neurodeficits due to suspected nerve injury in the perioperative period. Assessment and evaluation of the patient's symptoms can provide clues to the causative factors. Such causative factors can be corrected immediately to avoid further deterioration, or some may require further workup. The management plan for such a diagnosed nerve injury depends on the symptoms, the finding of the medical history, and the diagnostic imaging and tests. Simultaneous symptomatic relief in the form of pain medications, steroids, anti-inflammatory drugs, psychological counseling, and reassurance is essential to expedite treatment goals. Diagnosing and treating nerve injuries cannot be laid down as a straightforward part. It is a zigzag puzzle in its own right, playing with time and injury progression. Careful assessment to diagnose the extent of nerve damage plays an important role in treatment plans. It helps decide when to proceed and when to postpone, whether conservative strategies would suffice, or surgical repair would be required. Although most nerve injuries are self-limiting, some cases require surgical intervention that needs to be diagnosed early. The revolution was started by Sunderland in 1945 when he described neurosurgical techniques that drastically changed the entire scenario of nerve repairs. The ultimate effective treatment and full recovery may not be guaranteed, but attempts must be made to achieve the best results. With the patient's interests in mind, it is important to formulate a plan ensuring a good quality of life with minimal impact on their daily activities. Multifactorial nerve injury requires a multidisciplinary approach that primarily includes reassuring, psychological counseling, multimodal analgesia, and neurological and occupational consultations. This article describes the step-by-step approach known as the symptoms categorization-history taking-examination-diagnostic evaluations (SHED) approach to managing patients with peripheral nerve injuries. It also details the various modalities for diagnosing nerve injuries, sequential electrodiagnostic studies, and treatment plans depending on the type and extent of nerve injuries. It will help readers to design a treatment plan based on the patient's symptoms and evaluation results.

Multimodal Approach in Minimizing Transient Neurological Complications Following Single Shot Brachial Plexus Block: A Prospective Observational Study

PURPOSE

The aim of the study was to assess the benefit of a using multimodal approach, including injection pressure monitoring (IPM) and different techniques of nerve localization, with respect to complications following single-shot brachial plexus block (SSBPB).

METHODS

In this study, 238 adults (132 males and 106 females) undergoing upper-limb surgeries under peripheral nerve block (PNB) were evaluated. Of these, 198 patients were given supraclavicular block, and 40 patients received interscalene block using either ultrasound (USG) and peripheral nerve stimulation (PNS) or PNS alone. Injection pressure monitoring was used in 216 patients.

RESULTS

Transient neurological deficit (TND) was observed in six out of 198 patients where USG and NS were used along with IPM as opposed to 12 out of 18 patients without IPM (p<0.0001). In patients where only PNS was used, transient neurological deficit (TND) was seen in six out of 18 patients with IPM as opposed to all the patients (n=4) without IPM (p<0.02). Among the patients where injection pressure was monitored, six out of 198 patients developed TND when both USG and NS were used, compared to six out of 18 patients where only PNS was used (p<0.007).

CONCLUSION

Use of injection pressure monitoring along with different nerve localization techniques results in fewer transient neurological deficits.

Differences in incidence rate and onset timing of undiagnosed finger symptom among shoulder surgeries related to complex regional pain syndrome

The purpose of this study was to clarify the difference in onset timing and incidence of undiagnosed finger symptom (UDFS) between various shoulder surgical procedures. In this study, UDFS symptoms included the following four symptoms in the fingers;edema, limited range-of-motion, skin color changes, and abnormal sensations. UDFS cases were defined as those presenting with at least one UDFS. In result, the incidence rate of UDFS cases was 7.1% overall (58/816 shoulders), 7.4% (32/432) in arthroscopic rotator cuff repair (ARCR), 9.0% (11/122) in open rotator cuff repair (ORCR), 1.4% (2/145) in arthroscopic subacromial decompression (ASD), 13.2% (5/38) in open reduction and internal fixation (ORIF), 11.1% (3/27) in humeral head replacement, 4.8% (1/21) in anatomical total shoulder arthroplasty, and 12.9% (4/31) in reverse total shoulder arthroplasty cases. The Rate was significantly higher with ARCR compared to ASD (p<.01). About onset timing in weeks postoperatively, the ORIF group had a statistically earlier symptom onset than the Rotator cuff repair (ARCR + ORCR) group (2.4 weeks vs. 6.0 weeks, p<.01). When classifying the onset timing into before and after the removal of the abduction pillow, the ORIF group showed a statistically higher rate of onset before brace removal than the Rotator cuff repair groups (p<.01). Differences in UDFS among shoulder surgeries were demonstrated in this study. J. Med. Invest. 70 : 415-422, August, 2023.

Perioperative Management in Shoulder Arthroplasty: A Review of Current Practice

Perioperative management for patients undergoing shoulder arthroplasty has evolved significantly over the years to reduce overt complications and improve patient outcomes. The groundwork for perioperative care encompasses initial patient selection and education strategies for achieving successful outcome. Multimodal pain management strategies have advanced patient care with the increased use of new regional/local anesthetics. In addition, complications resulting from blood loss and transfusions have been curtailed with the use of synthetic antifibrinolytic agents. It remains critical for shoulder arthroplasty surgeons to optimize patients during the perioperative period through various modalities to maximize functional progression, outcomes, and patient's satisfaction following shoulder arthroplasty.

Traumatic needle damage to nerves during regional anesthesia: presentation of a novel mechanotransduction hypothesis

Despite advances in needle positioning techniques, nerve damage still occurs after regional anesthesia. Recognized causes include local anesthetic toxicity, subperineural injection, high subepineural fluid injection pressures and subepineural hematoma after forceful needle--nerve contact.We hypothesize that subperineural injection is still possible, but less likely to be the cause of nerve damage because needle penetration of fascicles and mechanical damage is difficult to achieve. High-resolution (75 µm) 40 MHz micro-ultrasound images of pig axillae show short-bevelled 22 g, 0.7 mm wide block needles that are three times larger than the average fascicle. Fascicular bundles are extremely difficult to puncture because they spin away on needle contact. Histology from fresh cadavers after supposed intrafascicular injection shows fluid spread within perineurium and intrafascicular perineural septae, but no breach of endoneurium or axons.We propose that mechanotransduction, the cellular changes that occur in response to force, contributes to nerve damage. Piezo ion channel proteins transduce force into electrical activity by rapid entry of cations into cells. Excessive Ca2+ influx into cells has the potential to inhibit nerve regeneration. Cellular changes include regulation of gene expression. The forces associated with purposeful needle insertion are generally unknown. Our experiments in the soft embalmed Thiel cadaver showed a lognormal range of forces between 0.6 N and 16.8 N on epineural penetration.We hypothesize that forceful needle injury may cause nerve damage by activation of Piezo receptors and release of intracellular Ca2.

Peripheral Nerve Injury After Upper-Extremity Surgery Performed Under Regional Anesthesia: A Systematic Review

Purpose

Peripheral nerve injury (PNI) is a known adverse event following upper-limb surgery performed under brachial plexus regional anesthesia (RA). When PNI is noted after surgery, patients and providers often have questions about which factors might have contributed to this complication. This systematic review evaluates the literature on hand and shoulder surgeries performed under ultrasound-guided, plexus RA to identify factors potentially associated with PNI, including the surgery location and block type. We hypothesized that shoulder surgery might be associated with an increased risk of PNI compared to hand surgery.

Methods

A systematic review of the relevant literature was performed in accordance with the Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines. Only prospective studies on the use of ultrasound-guided, preoperative, brachial plexus RA for hand or shoulder surgery on adult patients were included. Study groups were categorized according to surgery location and block type and compared across a number of factors via univariate and multivariate analyses.

Results

A total of 3,037 abstracts were screened; 192 full-text articles were independently reviewed by 2 of the authors; and 53 studies were included in the systematic review analysis. Following hand surgery, PNI was reported at an average rate of 1.35% ± 3.21% across 836 subjects in 40 study groups; after shoulder surgery, the average rate was 0.50% ± 1.57% across 3,383 subjects in 15 study groups. There was no statistically significant correlation between the incidence of PNI and surgery location (P =.70) or any of the most common approaches for brachial plexus anesthesia in the multivariate analysis.

Conclusions

This systematic review of over 50 articles on upper-limb surgery performed under RA shows no association between the incidence of PNI and the location of surgery or type of brachial plexus block.

Type of study/level of evidence

Diagnostic II.

Postoperative neurologic symptoms in the operative arm after shoulder surgery with interscalene blockade: a systematic review

OBJECTIVE

Postoperative neurologic symptoms (PONS) in the operative arm are important complications of shoulder surgery and interscalene blockade (ISB). This systematic review aimed to compare the risk of PONS between ISB and other techniques, and the relative safety of different agents used in ISB.

METHODS

Our systematic review followed Cochrane review methodology and was registered in PROSPERO. A search of MEDLINE (Ovid), EMBASE (Ovid), and CENTRAL (Wiley) from inception to June 2020 was completed. We included randomized or quasi-randomized trials of patients (> five years old) undergoing shoulder surgery with any ISB technique as an intervention, compared with any other nonregional or regional technique, or ISB of alternate composition or technique. The primary outcome was PONS (study author defined) assessed a minimum of one week after surgery.

RESULTS

Fifty-five studies totalling 6,236 participants (median, 69; range, 30-910) were included. Another 422 otherwise eligible trials were excluded because PONS was not reported. Heterogeneity in when PONS was assessed (from one week to one year) and the diagnostic criteria used precluded quantitative meta-analysis. The most common PONS definition, consisting of one or more of paresthesia, sensory deficit, or motor deficit, was only used in 16/55 (29%) trials. Risk of bias was low in 5/55 (9%) trials and high in 36/55 (65%) trials, further limiting any inferences.

CONCLUSION

These findings highlight the need for a standardized PONS outcome definition and follow-up time, along with routine, rigorous measurement of PONS in trials of ISB.

STUDY REGISTRATION

PROSPERO (CRD42020148496); registered 10 February 2020.

Peripheral Nerve Blocks Outperform General Anesthesia for Pain Control in Arthroscopic Rotator Cuff Repair: A Systematic Review and Meta-analysis

PURPOSE

The purpose of this review is to compare the effectiveness of different peripheral nerve blocks and general anesthesia (GA) in controlling postoperative pain after arthroscopic rotator cuff repair (ARCR).

METHODS

A Preferred Reporting Items for Systematic Reviews and Meta-Analyses-compliant systematic review was conducted for the period of January 1, 2005, to February 16, 2021, by searching the following databases: PubMed, Cochrane, Embase, and Arthroscopyjournal.org. The primary outcomes of interest included 1-hour, 24-hour, and 48-hour pain scores on a numeric rating scale or visual analog scale (VAS). Inclusion criteria were English language studies reporting on adults (≥18 years) undergoing ARCR with peripheral nerve blockade. To synthesize subjective pain score data at each evaluation time point across studies, we performed random-effects network meta-regression analyses accounting for baseline pain score as a covariate.

RESULTS

A total of 14 randomized controlled trials with 851 patients were included in the meta-analysis. Data from six different nerve block interventions, single-shot interscalene brachial plexus nerve block (s-ISB; 37.8% [322/851]), single-shot suprascapular nerve block (s-SSNB; 9.9% [84/851]), continuous ISB (c-ISB; 17.5% [149/851]), continuous SSNB (c-SSNB; 6.9% [59/851]), s-ISB combined with SSNB (s-ISB+SSNB; 5.8% [49/851]), s-SSNB combined with axillary nerve block (s-SSNB+ANB; 4.8% [41/851]), as well as GA (17.3% [147/851]) were included. Our meta-analysis demonstrated that c-ISB block had a significant reduction in pain score relative to GA at 1-hour postoperation (mean difference [MD]: -1.8; 95% credible interval [CrI] = -3.4, -.08). There were no significant differences in VAS pain scores relative to GA at 24 and 48 hours postoperatively. However, s-ISB+SSNB had a significant reduction in 48-hour pain score compared to s-ISB (MD = -1.07; 95% CrI = -1.92, -.22).

CONCLUSIONS

It remains unclear which peripheral nerve block strategy is optimal for ARCR. However, peripheral nerve blocks are highly effective at attenuating postoperative ARCR pain and should be more widely considered as an alternative over general anesthesia alone.

LEVEL OF EVIDENCE

Level II Systematic review and meta-analysis of Level I and II studies.

Continuous Catheter Techniques

Continuous peripheral nerve block catheters are simple in concept: percutaneously inserting a catheter adjacent to a peripheral nerve. This procedure is followed by local anesthetic infusion via the catheter that can be titrated to effect for extended anesthesia or analgesia in the perioperative period. The reported benefits of peripheral nerve catheters used in the surgical population include improved pain scores, decreased narcotic use, decreased nausea/vomiting, decreased pruritus, decreased sedation, improved sleep, and improved patient satisfaction.

Suprascapular nerve block and axillary nerve block versus interscalene nerve block for arthroscopic shoulder surgery: A meta-analysis of randomized controlled trials

BACKGROUND

The interscalene brachial plexus block (ISB) is a commonly used nerve block technique for postoperative analgesia in patients undergoing shoulder arthroscopy surgery; however, it is associated with potentially serious complications. The use of suprascapular nerve block (SSNB) and axillary Nerve Block (ANB) has been reported as an alternative nerve block with fewer reported side effects for shoulder arthroscopy. This review aimed to compare the impact of SSNB and ANB with ISB during shoulder arthroscopy surgery.

METHODS

A meta-analysis was conducted to identify relevant randomized or quasirandomized controlled trials involving SSNB and ISB during shoulder arthroscopy surgery. We searched Web of Science, PubMed, Embase, Cochrane Controlled Trials Register, Cochrane Library, Highwire, CNKI, and Wanfang database from 2010 through August 2021.

RESULTS

We identified 641 patients assessed in 10 randomized or quasirandomized controlled trials. Compared with the ISB group, the SSNB+ANB group had higher visual analog scale or numerical rating scale in PACU (P = .03), 4 hour (P = .001),6 hour after the operation (P = .002), and lower incidence of complications such as Numb/Tingling (P = .001), Weakness (P <.00001), Horner syndrome (P = .001) and Subjective dyspnea (P = .002). No significant difference was found for visual analog scale or numerical rating scale 8 hour (P = .71),12 hour (P = .17), 16 hour (P = .38),1day after operation (P = .11), patient satisfaction (P = .38) and incidence of complications such as hoarseness (P = .07) and nausea/vomiting (P = .41) between 2 groups.

CONCLUSION

Our high-level evidence has established SSNB+ ANB as an effective and safe analgesic technique and a clinically attractive alternative to interscalene block during arthroscopic shoulder surgery, especially for severe chronic obstructive pulmonary disease, obstructive sleep apnea, and morbid obesity. Given our meta-analysis's relevant possible biases, we required more adequately powered and better-designed randomized controlled trial studies with long-term follow-up to reach a firmer conclusion.

Ultrasound-guided interscalene block anesthesia performed by an orthopedic surgeon: a study of 1322 cases of shoulder surgery

Background

Interscalene blocks are becoming increasingly common for shoulder surgeries. This study primarily aimed to demonstrate the efficacy and complications and the secondarily to investigate the anesthesia-related time and patient satisfaction of an ultrasound-guided interscalene block performed by an orthopedic surgeon.

Methods

We retrospectively reviewed the medical records of 1322 consecutive patients (arthroscopic, 1225 cases; open, 97 cases) with a mean age of 64.2 years, who underwent shoulder surgery (arthroscopic or opensurgery) under an ultrasound-guided interscalene block performed by an orthopedic surgeon at a single institution between December 2012 and December 2019. We investigated patient satisfaction, block success rates, and complications and also compared the anesthesia-related time of an interscalene block with that of general anesthesia (428 cases, arthroscopic, 257 cases; open, 171 cases) for shoulder surgery with patients in the beach chair position during the same period. Difference between total anesthesia time and surgical time was defined as anesthesia-related time.

Results

Approximately 98.3% of patients were satisfied with an interscalene block, and the block success rate on the first attempt was 99.9%. Total complication incidence was 2.3%, with no recorded life-threatening complications. Anesthesia-related times were significantly shorter in the interscalene block group than those in the general anesthesia group (45 ± 14 min vs. 100 ± 26 min, P < .001).

Conclusion

An ultrasound-guided interscalene block performed by an orthopedic surgeon for shoulder surgery is effective and safe, requires less time, and has a high patient acceptance rate, making it a feasible and alternative to the block performed by anesthesiologists.

Does the use of periarticular anesthetic cocktail provide adequate pain control following shoulder arthroplasty?

BACKGROUND

Interscalene nerve block and liposomal bupivacaine have been found to provide adequate pain control following shoulder arthroplasty. We hypothesized that local infiltration of a periarticular cocktail would provide equivalent pain control compared to interscalene nerve block and liposomal bupivacaine.

METHODS

Eighty-seven patients undergoing primary shoulder arthroplasty were treated with local infiltration of a periarticular cocktail (200 mg of 0.5% ropivacaine, 1 mg epinephrine, and 30 mg ketorolac), local infiltration of liposomal bupivacaine, or preoperative interscalene nerve block. The outcomes of the study were postoperative visual analog scale scores, opioid consumption, length of stay, and complications.

RESULTS

A total of 30 patients receiving local infiltration of a periarticular cocktail, 26 receiving liposomal bupivacaine, and 31 receiving interscalene nerve block were included in the study. Patients who received local infiltration of a periarticular cocktail had a significantly lower mean visual analog scale when compared to interscalene nerve block and liposomal bupivacaine on postoperative day 0 (2.5 versus 4.0 versus 4.8, P = 0.001 and P < 0.001). Pain scores between postoperative day 0-3 were lower in patients who received local infiltration of a periarticular cocktail, but not significantly. Patients who received local infiltration of a periarticular cocktail required significantly less opioids than the interscalene nerve block group on postoperative day 0 (P < 0.001).

DISCUSSION

A decrease in early postoperative pain and opioid consumption was found with local infiltration of a periarticular cocktail when compared with interscalene nerve block and liposomal bupivacaine after shoulder arthroplasty.Level of evidence: Level II.

[Central neurological complication of an interscalene plexus catheter]

A 78-year-old patient received an interscalene plexus catheter for perioperative pain therapy during implantation of an inverse shoulder prothesis. After stimulation-assisted puncture under sonographic control, 25 ml of local anesthetic (LA) were first administered and then the catheter was placed using the through the needle technique. Immediately after the administration of another 5 ml of local anesthetic via the inserted catheter, the patient showed symptoms of total spinal anesthesia, so that she had to be intubated and ventilated. The following computed tomographic diagnostics of the neck revealed an intrathecal misalignment of the plexus catheter, the tip of which was lying dorsal to the vertebral artery at the level of the 5/6 cervical vertebrae. The catheter could then be removed without any problems and there were no neurological sequelae. The use of ultrasound with clear identification of the nerve roots C5-C7 and the surrounding structures provides additional security when installing an intrascalene catheter. The spread of the LA should be traceable at all times using ultrasound and should otherwise be immediately terminated. Furthermore, a strict adherence to the needle position while inserting the catheter without manipulation of the needle depth is necessary. The first injection of the catheter has to be performed under controlled conditions, preferably connected to surveillance monitors with neurological monitoring of the awake patient and control of vital signs with direct access to the emergency equipment.

The efficacy of periarticular injection intraoperatively for mini-open rotator cuff repair: A comparative study

BACKGROUND

The optimal postoperative analgesia after open rotator cuff repair surgery remains unclear. This study compared the use of a multimodal pain regimen including periarticular injection (PAI), with a control condition. We hypothesized that PAI leads to decreased opioid consumption and lower pain scores.

METHODS

The perioperative analgesic regimen was standardized and implemented from January 1, 2017 to December 31, 2017. The PAI was administered from July 1, 2017 to December 31, 2017. The historical control group was enrolled from January 1, 2017 to June 30, 2017. The evaluation items included assessments of pain using a 10-point visual analog scale (VAS) before and after the mini-open rotator cuff repair and on postoperative days 1, 2, and 3. The dose of ketorolac suppository and its side effects were also evaluated.

RESULTS

The VAS score on the day of the operation was significantly low in the PAI group and less incidence of night pain. The time point of the rescue drug was longer in the PAI group than the control group (12.7 hours vs. 0.62 hours; p < 0.01). No cardiac or central nervous system toxicity was observed.

DISCUSSION

In our study, PAI in the shoulder after mini-open rotator cuff repair showed effective pain control on the day of the surgery, postponed the time of the first dosage of intravenous pain medication, and reduced the total dosage of the intravenous pain medication.

Analgesic duration of interscalene block after outpatient arthroscopic shoulder surgery with intravenous dexamethasone, intravenous dexmedetomidine, or their combination: a randomized-controlled trial

PURPOSE

Both intravenous dexamethasone and dexmedetomidine prolong the analgesic duration of interscalene blocks (ISB) after arthroscopic shoulder surgery. This study compared their relative effectiveness and the benefit of their use in combination.

METHODS

This single-centre, double-blinded, parallel three-group superiority trial randomized 198 adult patients undergoing ambulatory arthroscopic shoulder surgery. Patients received preoperative ISB with 30 mL 0.5% bupivacaine and 50 µg dexmedetomidine or 4 mg dexamethasone or both of these agents as intravenous adjuncts. The primary outcome was analgesic block duration. Secondary outcomes included the quality of recovery 15 score (range: 0-150) on day 1 and postoperative neurologic symptoms in the surgical arm.

RESULTS

Block durations (n = 195) with dexamethasone (median [range], 24.5 [2.0-339.5] hr) and both adjuncts (24.0 [1.5-157.0] hr) were prolonged compared with dexmedetomidine (16.0 [1.5-154.0] hr). When analyzed by linear regression after an unplanned log transformation because of right-skewed data, the corresponding prolongations of block duration were 59% (95% confidence interval [CI], 28 to 97) and 46% (95% CI, 18 to 80), respectively (both P < 0.001). The combined adjuncts were not superior to dexamethasone alone (-8%; 95% CI, -26 to 14; P = 0.42). Median [IQR] quality of recovery 15 scores (n = 197) were significantly different only between dexamethasone (126 [79-149]) and dexmedetomidine (118.5 [41-150], P = 0.004), but by an amount less than the 8-point minimum clinically important difference.

CONCLUSION

Dexamethasone is superior to dexmedetomidine as an intravenous adjunct for prolongation of bupivacaine-based ISB analgesic duration. There was no additional benefit to using both adjuncts in combination.

TRIAL REGISTRATION

www.clinicaltrials.gov (NCT03270033); registered 1 September 2017.

Comparison of Ultrasound-Guided Supra-scapular Plus Axillary Nerve Block with Interscalene Block for Postoperative Pain Management in Arthroscopic Shoulder Surgery; A Double-Blinded Randomized Open-Label Clinical Trial

BACKGROUND

Post-arthroscopic shoulder surgery pain is severe enough to interfere with initial recovery and rehabilitation.

OBJECTIVES

We aimed to evaluate the analgesic effects of postoperative ultrasound-guided suprascapular plus axillary nerve blocks superficial subepidermal axon bundles (SSAB) with interscalene block (ISB) in arthroscopic shoulder surgery.

METHODS

In this single-blind randomized, open-label clinical trial, 80 candidates of elective arthroscopic shoulder surgery were randomly allocated to receive either SSAB or ISB at a postoperative care unit. The severity of resting and changing position pain was measured using visual analogue scale (VAS) score at 4h, 8h, 12h, 16h, and 24h, postoperatively. Timing of first opioid request, 24h dose requirement, patients' satisfaction rate, and side effects were also recorded. All registered data were analyzed using SPSS software version 23 for Windows (SPSS, Chicago, IL).

RESULTS

Resting and changing position pain scores were comparable between SSAB and ISB groups in the most time intervals. At 12h, moving and resting pain was significantly lower in ISB than SSAB group, while moving pain was more severe in ISB group at 24h assessment. Patient satisfaction scores were comparable between the two groups except for 12h assessment. Time to first analgesic requirement and total dose of 24h opioid requirement were not significantly different between the two groups.

CONCLUSIONS

Suprascapular plus axillary nerve block could be an effective and safe alternative for interscalene block for pain management after arthroscopic shoulder surgery.

Cost of Arthroscopic Rotator Cuff Repairs Is Primarily Driven by Procedure-Level Factors: A Single-Institution Analysis of an Ambulatory Surgery Center

PURPOSE

To identify intraoperative drivers of cost associated with arthroscopic rotator cuff repairs (RCRs) through analysis of an institutional database.

METHODS

This was a single-institution retrospective review of arthroscopic RCRs performed at an ambulatory surgical center between November 2016 and July 2019. Patient-level factors analyzed included age, sex, insurance type (private, Medicare, Medicaid, self-pay, and other government), American Society of Anesthesiologists grade (I, II, III, and missing), and Charlson comorbidity index (0, 1, 2, and ≥3). Procedure-level factors included use of biologics (decellularized dermal allograft or bioinductive healing implant), anesthesia type (regional block, monitored anesthesia care, or general), number of anchors and sutures, additional procedures (biceps tenodesis, distal clavicle resection, subacromial decompression), and operative time. Multivariate linear regression analysis was used to identify factors significantly associated with higher or lower charges.

RESULTS

A total of 712 arthroscopic RCRs were included. The risk-adjusted operative charges were $19,728 (95% confidence interval $16,543 to $22,913). The above factors predicted nearly 65% of the variability in operative charges. The only patient-level factor significantly associated with lower charges was female sex (- $1,339; P = .002). Procedure-level factors significantly associated with higher charges were use of biologics (+ $17,791; P < .001), concurrent open biceps tenodesis (+ $4,027; P < .001), distal clavicle resection (+ $2,266; P = .039), use of regional block (+ $1,256; P = .004), number of anchors (+ $2,245/anchor; P < .001), and increasing operative time ($26/min). Other factors had no significant association.

CONCLUSIONS

Procedural factors are the most significant drivers of operative cost in arthroscopic RCRs, such as quantity and type of implants; additional procedures such as biceps tenodesis and distal clavicle resection; and perioperative conditions such as type of anesthesia and total operating room time. Overall, patient-level factors were not shown to correlate well with operative costs, other than lower charges with female sex.

LEVEL OF EVIDENCE

IV, economic study.

Local Anesthetic-Induced Central Nervous System Toxicity during Interscalene Brachial Plexus Block: A Case Series Study of Three Patients

Local anesthetics are commonly administered by nuchal infiltration to provide a temporary interscalene brachial plexus block (ISB) in a surgical setting. Although less commonly reported, local anesthetics can induce central nervous system toxicity. In this case study, we present three patients with acute central nervous system toxicity induced by local anesthetics applied during ISB with emphasis on neurological symptoms, key neuroradiological findings and functional outcome. Medical history, clinical and imaging findings, and outcome of three patients with local anesthetic-induced toxic left hemisphere syndrome during left ISB were analyzed. All patients were admitted to our neurological intensive care unit between November 2016 and September 2019. All three patients presented in poor clinical condition with impaired consciousness and left hemisphere syndrome. Electroencephalography revealed slow wave activity in the affected hemisphere of all patients. Seizure activity with progression to status epilepticus was observed in one patient. In two out of three patients, cortical FLAIR hyperintensities and restricted diffusion in the territory of the left internal carotid artery were observed in magnetic resonance imaging. Assessment of neurological severity scores revealed spontaneous partial reversibility of neurological symptoms. Local anesthetic-induced CNS toxicity during ISB can lead to severe neurological impairment and anatomically variable cerebral lesions.

Comparison of Analgesic Efficacy of Ultrasound-Guided Interscalene Block Versus Continuous Subacromial Infusion for Postoperative Analgesia Following Arthroscopic Rotator Cuff Repair Surgeries: A Randomized Trial

Background: Arthroscopic rotator cuff repair surgery may lead to significant postoperative pain. Interscalene block (ISB) is an effective analgesic technique in these surgeries but there is a risk of the phrenic blockade. Subacromial local anesthetic infiltration is a phrenic sparing alternative technique for postoperative analgesia. The primary aim of our study was to compare the ISB with a continuous subacromial infusion (SAC) with regard to postoperative analgesia.

Methods: This prospective randomized, interventional parallel arm trial was conducted in 60 ASA grade I and II, adult patients (30 patients in each group) posted for arthroscopic rotator cuff repair surgery. Patients were randomly assigned to receive either ultrasound-guided ISB (Group ISB: 15 ml of 0.75% ropivacaine) or continuous SAC (Group SAC: 15 ml 0.75% ropivacaine as a subacromial injection by ultrasound guidance and infusion of 3 ml/hour of 0.5% ropivacaine through the catheter placed subacromial by the surgeon). Intraoperative hemodynamic parameters, visual analog scores (VAS), and rescue analgesic requirements for 24 hours, patient satisfaction, and complications were recorded.

Results: Rescue analgesic requirement was significantly higher in SAC at zero hours (P=0.000), while it was significantly higher in ISB at 12 hours (P=0.02). The VAS scores were comparable at all time points and patient satisfaction at 24 hours was similar. None of the patients had rated satisfaction related to pain relief as poor in any group. Complications like ptosis and motor weakness were seen only with ISB.

Conclusion: Both the techniques provided effective analgesia and comparable patient satisfaction with lesser incidence of complications in the SAC group. ISB provided more effective immediate postoperative pain relief while SAC was more effective in delayed analgesia for arthroscopic rotator cuff repair surgeries. SAC can be considered a reasonably safe alternative to ISB in patients with contraindications to the latter.

Permanent hemidiaphragmatic paresis after interscalene brachial plexus block: a case report

Interscalene brachial plexus block has been widely used in shoulder surgery. We report one case of long-term phrenic palsy following ultrasound-guided interscalene brachial plexus block and we will discuss the possible etiology and mechanism of this disability. For painful shoulder surgery, ultrasound-guided interscalene brachial plexus block remains topical. Alternative blocks, such as suprascapular and axillary blocks, may be reserved for patients with pre-existing respiratory pathology.

Risk factors for complications and return to the emergency department after interscalene block using liposomal bupivacaine for shoulder surgery

BACKGROUND

Exparel (liposomal bupivacaine) has recently gained favor for use in interscalene regional blocks for shoulder surgery. While effective for pain relief, this does have adverse effects that can lead to postoperative emergency department (ED) visits. This study aimed to identify any patient risk factors that are associated with complications leading to ED return visits owing to interscalene blocks using Exparel before shoulder surgery.

METHODS

A retrospective chart review was performed for all patients undergoing shoulder surgery with an Exparel interscalene block in an 8-month period. For each patient, demographic information, comorbidities, type of block, postoperative complications, ED return visits, and readmissions were recorded. The 5-factor modified Frailty Index score and the Charlson Comorbidity Index score were calculated. Univariate and multivariate logistic regressions were conducted to identify risk factors associated with increased complications and return to the ED.

RESULTS

Overall, 352 patients were included; most patients were men, were aged between 51 and 70 years, and had a body mass index of 25.0-35.0. Postoperative complications related to the Exparel interscalene block occurred in 58 patients (16.5%), including 37 minor complications (10.5%) and 21 major complications (6.0%) that led to return ED visits. Univariate analysis yielded American Society of Anesthesiologists (ASA) score (P = .03) as a significant predictor of minor complications. Multivariate logistic regression analysis yielded ASA score (P = .096; odds ratio, 1.64) as trending toward being a significant risk factor for minor complications. Univariate analysis yielded age (P = .006), ASA score (P = .009), and Charlson Comorbidity Index score (P = .002) as significant predictors of major complications. Multivariate logistic regression analysis yielded ASA score (P = .049; odds ratio, 2.25) as the only significant risk factor for major complications.

CONCLUSION

Surgeons and anesthesiologists should strongly consider a patient's ASA score, in addition to his or her pulmonary and cardiac history, when deciding whether the patient is an appropriate candidate for an interscalene regional block using Exparel for shoulder surgery.

Arthroscopic capsular release and continuous upper arm brachial block in frozen shoulder - A midterm outcome analysis

OBJECTIVE

This prospective study aims to evaluate the efficacy of Continuous upper arm brachial block (modified interscalene block) with an arthroscopic capsular release in the outcome of resistant frozen shoulder cases.

METHODS

We studied 123 patients who underwent arthroscopic capsular release and subacromial decompression for resistant frozen shoulder cases between June 2016 and July 2019. Postoperative analgesia was provided with Continuous upper arm brachial block and ambulatory patient-controlled analgesia pump for 2-3 weeks. The patients were started on regular physiotherapy on the first postoperative day. All the patients were followed up at 3rd week, 6th week, 3rdmonth, 6th month, 1st year, and 2nd year with VAS and Constant-Murley scores.

RESULTS

At a mean follow-up period of 18 months, there was a statistically significant improvement in the range of motion, VAS scores, and Constant-Murley scores postoperatively (p < .01). None of the cases required postoperative opioid administration for pain control. Minor neurological complications like recurrent laryngeal nerve palsy and Horner's syndrome were seen in few cases that resolved with titration of the drug dose.

CONCLUSION

Our study verifies the use of continuous upper arm brachial block (CUABB) with a portable infusion pump for 2-3 weeks in arthroscopic capsular release for resistant frozen shoulder cases. It significantly reduced postoperative pain in the initial two weeks that aided with early recovery of the shoulder movements and functions without an increased incidence of acute or chronic neurologic complications.

Incidence and etiology of postoperative neurological symptoms after peripheral nerve block: a retrospective cohort study

Background

Nerve injury from peripheral nerve block (PNB) is an uncommon but potentially serious complication. We present a retrospective cohort study to evaluate the incidence and etiology of new postoperative neurological symptoms after surgery and regional anesthesia.

Methods

We performed a retrospective cohort study of all PNBs performed on elective orthopedic and plastic surgical patients over 6 years (2011–2017). We collected patient and surgical data, results of neurophysiological and imaging tests, neurology and chronic pain consultations, etiology and outcome for patients with prolonged neurological symptoms (lasting ≥10 days).

Results

A total of 26 251 PNBs were performed in 19 219 patients during the study period. Transient postoperative neurological symptoms (<10 days) were reported by 14.4% (95% CI 13.1% to 15.7%) of patients who were reached by telephone follow-up. Prolonged postoperative neurological symptoms (≥10 days) were identified and investigated in 20 cases (1:1000, 95% CI 0.6 to 1.6). Of these 20 cases, three (0.2:1000, 95% CI 0.04 to 0.5) were deemed to be block related, seven related to surgical causes, three due to musculoskeletal causes or pain syndromes, one was suspected of having an inflammatory etiology and six remained of undetermined etiology. Of those who completed follow-up, 56% had full recovery of their symptoms with the remaining having partial recovery.

Conclusion

This retrospective review of 19 219 patients receiving PNBs for anesthesia or analgesia suggests that determining the etiology and causative factors of postoperative neurological symptoms is a complex, often challenging process that requires a multidisciplinary approach. We suggest a classification of cases based on the etiology. A most likely cause was identified in 70% of cases. This type of classification system can help broaden the differential diagnosis, help consider non-regional anesthesia and non-surgical causes and may be useful for clinical and research purposes.

Short-Term Effects of Deliberate Subparaneural or Subepineural Injections With Saline Solution or Bupivacaine 0.75% in the Sciatic Nerve of Rabbits

Background: Ultrasound (US)-guided techniques for peripheral nerve blockade have revealed that intraneural injections are relatively frequent and not necessarily associated with neurological deficits. Objectives: To evaluate the short-term effects of deliberate injections performed under direct vision in two different sites of the sciatic nerve (ScN). Material and Methods: Seventy-two New Zealand white rabbits randomly assigned to one of four experimental groups (n = 18) were employed. All procedures were conducted at a proximal femoral level where the ScN incorporates the common peroneal nerve and the tibial nerve (TN). Fixed volumes of 0.5 ml of saline solution (ES group) or bupivacaine 0.75% (EB group) were administered extrafascicularly inside the paraneurium of the ScN or intrafascicularly (IS and IB groups) under the epineurium of the TN. Cross-sectional area (CSA) and relative echogenicity (RE) of the entire ScN were determined by US before injections, after injections, and at 3 and 7 days. ScN samples were obtained for structural and ultrastructural histopathological studies. Proprioceptive, sensorial, and motor function were clinically evaluated on a daily basis. Results: The CSA of the ScN increased significantly immediately after injections when compared with pre-injection values in all groups (p < 0.05). The RE of the ScN decreased in relation to pre-injection values in all groups (p < 0.05). The CSA and RE of the ScN returned to normal values 7 days after injections in almost all groups. Injected nerves showed histological signs of mild perineural inflammation. Histopathological scores were not significantly different between groups (p > 0.05). The architecture of the ScN was preserved in all rabbits at 3 days and in 31/32 rabbits at 7 days. A focal area of damaged nerve fibers with degeneration of the axons and myelin sheath affecting the TN was observed in one rabbit of the IB group. Nerve function was not clinically impaired in any case. Conclusion: Despite the lack of severe nerve disruption observed in most rabbits, the evidence of a focal area of damaged nerve fibers in one rabbit injected intrafascicularly with bupivacaine confirms that intrafascicular injections should be avoided as they may increase the risk of nerve damage.

A prospective study of two methods of analgesia in shoulder arthroscopic procedures as day case surgery

BACKGROUND & PURPOSE

The recent advances in anaesthesia and analgesia have significantly improved the early recovery and effective post-operative pain control in day care surgery e.g. shoulder arthroscopic procedures. Adequate analgesia improves the early rehabilitation for a better outcome. We prospectively evaluated the post-operative pain relief following the two methods of analgesia i.e. regional Inter-scalene block (ISB) vs Intra-articular (IA) injection using 0.5% Chirocaine in various therapeutic arthroscopic shoulder procedures.

METHODS

A prospective comparative study was performed on a group of 105 patients (ASA grade I or II) who underwent the following procedures at two different hospitals: diagnostic arthroscopy, subacromial decompression (SAD) alone, SAD in combination with mini open cuff repairs or distal clavicle excision, anterior stabilization (Bankart's repair) and inferior capsular shift. A successful Inter-scalene block (0.5% Chirocaine-30mls) preceded the general anaesthesia (Group 1-52 patients). Local intra-articular infiltration (0.5% Chirocaine - 20 mls) was given postoperatively (Group 2-53 patients). Post operatively visual analogue scores (VAS) from 0 (no pain) to 10 (severe pain) were assessed in post-anaesthesia care unit (PACU), at 4hrs, at 24hrs and at 48 h. The amount of morphine consumption for the first 2 days after surgery was recorded.

RESULTS

Patient characteristics were similar in both groups at both the hospitals. The median postoperative pain score of VAS <3 was observed in both groups. Significant difference (p < 0.0001) was observed in the VAS scores between the two groups at all the time intervals. The mean length of adequate sensory block in group 1 was significantly higher than in group 2 [20.5 h: 4.2 h] (p < 0.001). The mean analgesic (morphine) consumption was lower in Group 1 as compared to Group 2 [4.6 mg/24 h: 18.8mg/24 h](p < 0.0001). Bone shaving procedures e.g. SAD, SAD + Rotator Cuff repair, SAD + Lateral clavicular excision required significantly higher analgesia in both groups compared to the soft tissue procedures.

CONCLUSION

Single dose ISB provided longer and effective postoperative analgesia. The bone shaving procedures required more analgesia in IA Group as compared to ISB Group.

Patient Complications after Interscalene Block: A Retrospective Comparison of Liposomal Bupivacaine to Nonliposomal Bupivacaine

Background

The purpose of this study was to investigate if the addition of liposome bupivacaine (LB) to an interscalene block (ISB) had an effect on the number of patients with surgical- or block-related complications.

Methods

This was a single-center retrospective chart view performed by identifying patients who received an ISB from January 1, 2014, through April 26, 2018, at the University of Minnesota. 1,518 patients were identified who received an ISB (LB = 784, nonliposomal bupivacaine = 734). Patients were divided into two groups those who did receive liposome bupivacaine in their ISB and those who did not receive liposome bupivacaine in their ISB. Medical records were individually reviewed for surgical procedure, block medications, complications related to the block or surgical procedure, phone calls to the healthcare system for issues related to opioids or pain within 3 and within 30 days, readmissions within 30 days, and emergency room visits for complications within 3 and 30 days.

Results

There was no significant difference in the number of patients with surgical or anesthetic complications. Only phone calls for pain within 3 days were significantly different. The LB group had 3.2% of patients call compared to 5.6% in the nonliposomal bupivacaine group (aOR = 1.71 (95% CI: 1.04–2.87), p=0.036). We found no significant difference in any of the other secondary outcomes.

Conclusions

The use of LB in an ISB demonstrated no significant difference compared to nonliposomal bupivacaine in numbers of complications, emergency room visits, and readmissions.

Efficacy of local infiltration anesthesia versus interscalene nerve blockade for total shoulder arthroplasty

Background

Optimal modalities for pain control in shoulder arthroplasty are not yet established. Although regional nerve blockade has been a well-accepted modality, complications and rebound pain have led some surgeons to seek other pain control modalities. Local injection of anesthetics has recently gained popularity in joint arthroplasty. The purpose of this study was to evaluate the effectiveness and complication rate of a low-cost local anesthetic injection mixture for use in total shoulder arthroplasty (TSA) compared with interscalene brachial plexus blockade.

Methods

A total of 314 patients underwent TSA and were administered general anesthesia with either a local injection mixture (local infiltration anesthesia [LIA], n = 161) or peripheral nerve block (PNB, n = 144). Patient charts were retrospectively reviewed for postoperative pain scores, 24-hour opioid consumption, and 90-day postoperative complications.

Results

Immediate postoperative pain scores were not significantly different between groups (P = .94). The LIA group demonstrated a trend toward lower pain scores at 24 hours postoperatively (P = .10). Opioid consumption during the first 24 hours following surgery was significantly reduced in the LIA group compared with the PNB group (P < .0001). There was a trend toward fewer postoperative nerve and cardiopulmonary complications in the LIA group than the PNB group (P = .22 and P = .40, respectively)

Conclusion

Periarticular local injection mixtures provide comparable pain control to regional nerve blocks while reducing opioid use and postoperative complications following TSA. Local injection of a multimodal anesthetic solution is a viable option for pain management in TSA.

Understanding and Treating Iatrogenic Nerve Injuries in Shoulder Surgery

As surgical techniques and technology continue to advance in shoulder surgery along with the increased use of regional anesthesia, it is important to remember that iatrogenic nerve injuries remain a possible complication. Iatrogenic nerve injuries associated with shoulder surgery lead to patient disability and distress, increased healthcare costs, and possibly additional procedures. To obtain the best possible outcome for the patient after the nerve injury has been discovered, a timely appreciation of the management options is necessary rather than expectant management. Early recognition, appropriate neurodiagnostic testing, and prompt treatment or referral are mandatory for optimal outcomes.

Subacromial analgesia via continuous infusion catheter vs. placebo following arthroscopic shoulder surgery: a systematic review and meta-analysis of randomized trials

BACKGROUND

Subacromial analgesia (SAA) is hypothesized to reduce pain after arthroscopic shoulder surgery by delivering a continuous infusion of local anesthetic directly to the surgical site. The purpose of this systematic review and meta-analysis was to evaluate the efficacy of SAA vs. placebo for pain relief after arthroscopic subacromial shoulder procedures.

METHODS

MEDLINE, Embase, PubMed, and the Cochrane Central Register of Controlled Trials were searched for randomized controlled trials comparing SAA with placebo after arthroscopic shoulder surgery. Outcomes collected included pain scores (converted to equivalent ordinal visual analog scores; minimal clinically important difference 1.4 cm), oral morphine equivalents used postoperatively, and catheter-related complications. Meta-analysis was performed via a random-effects model. Included trials underwent a risk of bias and quality of evidence assessment.

RESULTS

Nine studies involving 459 participants were included. There were no clinically significant changes for pain scores in SAA at 6-, 12-, 24-, and 48-hour postoperative timepoints. Patients receiving SAA used less morphine equivalents of pain medication at 12 hours only (-0.37 mg, 95% confidence interval: -0.63 to -0.11), but there was no significant difference at 24 and 48 hours. There were no major complications (infection or reoperation). Included trials demonstrated a moderate risk-of-bias, and low to very low quality of evidence for primary outcomes.

CONCLUSION

Subacromial continuous infusion of local anesthetic does not provide a clinically significant benefit compared with placebo as part of a multimodal analgesia regime after arthroscopic subacromial surgical procedures. Future, high-quality trials are required to further assess the efficacy of SAA against placebo.

Peri-articular infiltration analgesia for shoulder surgery: a systematic review and meta-analysis

Effective analgesic alternatives to interscalene brachial plexus block are sought for shoulder surgery. Peri-articular infiltration analgesia is a novel, less invasive technique, but evidence surrounding its use is unclear. This systematic review and meta-analysis aims to evaluate the utility of peri-articular infiltration analgesia in shoulder surgery. We searched literature for trials comparing peri-articular infiltration analgesia with control or with interscalene brachial plexus block. Control groups received no intervention, placebo or systemic opioids. The primary outcome was cumulative oral morphine equivalent consumption during the first 24 h postoperatively. Secondary outcomes included: rest pain scores up to 48 h; risk of side-effects; and durations of post-anaesthetic care unit and hospital stay. Data were pooled with random-effects modelling. Seven trials (383 patients) were included. Compared with control, peri-articular infiltration analgesia reduced 24-h oral morphine consumption by a mean difference (95%CI) of -38.0 mg (-65.5 to -10.5; p = 0.007). It also improved pain scores up to 6 h, 36 h and 48 h, with the greatest improvement observed at 0 h (-2.4 (-2.7 to -1.6); p < 0.001). Peri-articular infiltration analgesia decreased postoperative nausea and vomiting by an odds ratio (95%CI) of 0.3 (0.1-0.7; p = 0.006). In contrast, peri-articular infiltration analgesia was not different from interscalene brachial plexus block for analgesic consumption, pain scores or side-effects. This review provides moderate evidence supporting peri-articular infiltration for postoperative analgesia following shoulder surgery. The absence of difference between peri-articular infiltration analgesia and interscalene brachial plexus block for analgesic outcomes suggests that these interventions are comparable, but further trials are needed to support this conclusion and identify the optimal peri-articular infiltration technique.

Regional anaesthesia for surgical repair of proximal humerus fractures: a systematic review and critical appraisal

INTRODUCTION

Regional anaesthesia (RA) is often used in shoulder surgery because it provides adequate postoperative analgesia and may enhance the patient outcome. RA reduces overall opioid consumption and is frequently used in enhanced recovery programs to decrease hospital stay. However, there is very limited literature confirming these advantages in the surgical repair of proximal humerus fractures. This paper reviews the current literature on the use of RA in pain management after surgical repair of these fractures and evaluates the effect of RA on the functional outcome, length of stay in hospital, and health care expenditure.

MATERIALS AND METHODS

The PubMed, Embase, Web of Science, and Cochrane Library databases were searched up to March 1, 2018. Studies investigating the use of RA in the management of proximal humerus fractures were included.

RESULTS

Eleven studies (containing 1872 patients) were eligible for inclusion. The analgesic effect of RA was investigated in eight studies that confirmed its pain-relieving ability. Two studies measured functionality and length of hospitalization and suggested that RA improved function and shortened the stay in hospital. Nine papers mentioned side effects associated with RA while three articles claim that RA decreases the incidence of adverse events associated with general anaesthesia.

CONCLUSIONS

This systematic review suggests that RA is a good option for postoperative analgesia in patients undergoing surgical repair of a proximal humerus fracture and is associated with fewer adverse events, a shorter recovery time, and a better functional outcome than those achieved by general anaesthesia alone. However, given the limited amount of data available, conclusions need to be made with caution and prospective studies are needed in the future.