EUS-CGN versus EUS-CPN in pancreatic cancer: A qualitative systematic review.

BACKGROUND: Comparison between endosonographic ultrasonography (EUS)-guided celiac ganglia neurolysis (CGN) and EUS-guided celiac plexus neurolysis (CPN) in pain management for pancreatic cancer has engendered controversy. To analyze the effectiveness and safety of EUS-CGN and figure out whether EUS-CGN is better than EUS-CPN, a qualitative systematic review was conducted. METHODS: Studies were searched from Cochrane Central Register of Controlled Trials, MEDLINE, and EMBASE up to April 2020. We only included studies with full-text and in English and assessed study quality with Newcastle-Ottawa Scale or Cochrane risk-of-bias tool. We recorded details of study design, participants, procedure performed, protocol of follow-up, pain response, quality of life, survival, and adverse events. The study was conducted under Preferred Reporting Items for Systematic Reviews and Meta-Analyses statement 2009. RESULTS: Five studies involving 319 patients were included. Short-term pain response rates ranged from 65.0% to 88.46% in EUS-CGN group and most studies reported its superiority over EUS-CPN. As for adverse events, the incidence of transient hypotension and gastrointestinal symptoms seemed comparable, while results of initial pain exacerbation varied among studies. Besides, EUS-CGN might provide a shorter survival. CONCLUSION: EUS-CGN can be safely performed while it may shorten survival. In terms of short-term pain response, EUS-CGN is better than EUS-CPN while no conclusion of long-term pain control can be drawn.

Evaluation of the B-Smart manometer and the CompuFlo computerized injection pump technology for accurate needle-tip injection pressure measurement during peripheral nerve blockade.

BACKGROUND AND OBJECTIVES: The exact mechanism of peripheral nerve blocks causing/leading to nerve injury remains controversial. Evidence from animal experiments suggests that intrafascicular injection resulting in high injection pressure has the potential to rupture nerve fascicles and may consequently cause permanent nerve injury and neurological deficits. The B-Smart (BS) in-line manometer and the CompuFlo (CF) computerized injection pump technology are two modalities used for monitoring pressure during regional anesthesia. This study sought to explore the accuracy of these two technologies in measuring needle-tip pressures in a simulated environment. METHODS: In seven simulated needle-syringe combinations, the BS and the CF devices were connected in series through a closed system and attached to a digital manometer at the tip of various needles. The pressures were evaluated in three trials per needle-syringe combination. Sensitivity, specificity, positive predictive value, negative predictive value, and accuracy (F1 Score) were determined for each needle type and overall. RESULTS: For pressures ≥15 psi and ≥20 psi, respectively, the CF device demonstrated a sensitivity of 100%, 100%; specificity of 96%, 98%; positive predictive value 93%, 93%; and negative predictive value of 100%, 100%. The BS device demonstrated a sensitivity of 60%, 100%; specificity of 99%, 95%; positive predictive value of 96%, 85%; and negative predictive value of 85%, 100%. Accuracy, as measured by the F1 Score, for detecting a pressure of ≥15 psi was 0.96 for the CF and 0.74 for the BS. CONCLUSIONS: Future research is needed to explore in-vivo performance and evaluate whether either of these devices can impact on clinical outcomes.

Ultrasound-guided single injection versus continuous sciatic nerve blockade on pain management and mobilisation after total knee arthroplasty (CoSinUS trial): A randomised, triple-blinded controlled trial.

BACKGROUND: Combining continuous femoral nerve blockade with single injection sciatic nerve blockade is standard peripheral nerve block practice for total knee arthroplasty (TKA) during the first 24 postoperative hours. OBJECTIVES: To assess the analgesic benefits and mobilisation capability of continuous sciatic blockade in conjunction with continuous femoral nerve blockade for 72 h after arthroplasty. DESIGN: Randomised, triple-blinded controlled trial. SETTING: Single-Centre, German University Hospital. PATIENTS: In total, 50 patients receiving continuous femoral nerve blockade (5 ml h ropivacaine 0.2%) for TKA under general anaesthesia. INTERVENTIONS: Patients were randomised to receive a sciatic nerve catheter with an initial dose of 10 ml ropivacaine 0.2% followed by either continuous double-blinded application of 5 ml h ropivacaine 0.2% (CO) or 5 ml h saline infusion (SIN). MAIN OUTCOME: Measures primary endpoint: cumulative morphine consumption until 48 h postoperatively. Further endpoints included morphine consumption, pain scores, mobilisation, dynamometry until postoperative day 3. RESULTS: Median [25th to 75th percentiles] cumulative morphine consumption at postoperative day 2 differed significantly between groups (CO 15 mg [11 to 25] versus SIN, 43 mg [27 to 67.5, P < 0.0001) in the 48 patients in the final analysis. Overall pain scores were comparable at rest and during stress at each time point. However, significantly higher pain scores of the popliteal fossa were observed in the SIN group. Mobilisation was comparable between groups. CONCLUSION: This trial demonstrates the superior analgesic effects of continuous sciatic nerve block compared with a single injection in combination with continuous femoral blockade during the first 72 h after TKA. However, mobilisation capability was impaired in both groups. Improved pain control from two catheters needs to be balanced against the potential risks of impaired mobilisation and patient falls. TRIAL REGISTRATION: DRKS - German clinical trials register (no: DRKS00010152).

Improving Performance by Monitoring the Success Rate of Peripheral Nerve Blocks.

In our hospital, we introduced a system to measure the collective and individual efficacy of brachial plexus and popliteal nerve blocks with the objective to create transparency as an instrument for monitoring and improvement. Initially, individual results were anonymous, but after 1 year anonymity was lifted within the team of anesthesiologists and results are now discussed quarterly. Collective performance of interscalene, supraclavicular, and popliteal blocks improved significantly over time. Sharing and discussing collective and individual performance has resulted in critical self-appraisal and increased willingness to learn from each other and strengthened the team's ambition for further improvement.

Anterior Suprascapular Nerve Block Versus Interscalene Brachial Plexus Block for Shoulder Surgery in the Outpatient Setting: A Randomized Controlled Patient- and Assessor-Blinded Trial.

BACKGROUND AND OBJECTIVES: The interscalene brachial plexus block (ISB), a potent option to control pain after shoulder surgery, has notable adverse effects. The anterior suprascapular nerve block (SSNB) might provide comparable analgesia and cause less grip-strength impairment. These characteristics were studied in this randomized controlled patient- and assessor-blinded trial. METHODS: Outpatients were randomized to single-shot ultrasound-guided SSNB (10 mL ropivacaine 1%) or ISB (20 mL ropivacaine 0.75%) before general anesthesia for arthroscopic shoulder surgery. Pain (Numerical Rating Scale, 0-10), grip strength, degree of satisfaction, and strength of recommendation were assessed. RESULTS: We randomized 168 patients to each group and analyzed 164 in the SSNB group and 165 in the ISB group. Nerve blocks were successful in 98% of the patients from each group. Both procedures provided good postoperative analgesia, and the mean pain level for SSNB was slightly but significantly lower by 0.32 units (95% confidence interval, 0.18-0.46; P < 0.001) and noninferior given a margin of 1.1 units; P < 0.001. Within the first 24 hours, 162 (99%) of SSNB patients had unimpaired grip strength compared to 81 (49%) of ISB patients (P < 0.001). The multiple primary outcome, superior unimpaired grip strength, and noninferior pain control was significant; P < 0.001. Compared to ISB patients (n = 130 [79%]), significantly more SSNB patients (n = 150 [91%]) were satisfied/highly satisfied. Patients in the SSNB group were more likely to recommend the procedure highly. CONCLUSIONS: For outpatients undergoing arthroscopic shoulder surgery under general anesthesia, the SSNB seems preferable to ISB. It provides excellent postoperative analgesia without exposing patients to impaired mobility and to risks of the more potent but also more invasive ISB.

Effect of Stellate Ganglion Block on Specific Symptom Clusters for Treatment of Post-Traumatic Stress Disorder.

This study assessed which symptoms are most impacted following stellate ganglion block (SGB) used to treat post-traumatic stress disorder (PTSD) symptoms. 30 active military service members with combat-related PTSD self-referred to their physician and psychologist. Patients were offered a SGB as part of their treatment program. Primary outcome was the magnitude of change for the 17 items on the PTSD Checklist-Military (PCL-M), which was administered the week before SGB, 1 week after SGB, and 2 to 4 months later. Mean PCL-M score decreased from 49 at baseline to 32, 1 week after the procedure (p < 0.001). 2 to 4 months after SGB, patients maintained an average PCL-M of 32. Patients reported greatest improvement in the first week after SGB for the following symptoms: irritability or angry outbursts, difficulty concentrating, and sleep disturbance. 2 to 4 months later, patients reported greatest improvement in the following: feeling distant or cut off, feeling emotionally numb, irritability or angry outbursts, and difficulty concentrating. SGB is a safe procedure that may provide extended relief for all clusters of PTSD symptoms. As a result of the significant reduction in hyperarousal and avoidance symptoms observed, this study supports incorporation of SGB into PTSD treatment plans.

A randomized comparison between ultrasound- and fluoroscopy-guided c7 medial branch block.

BACKGROUND: Because of its location in the lower neck and anatomical variability, the C7 medial branch represents a challenging target for local anesthetic blocks. Although ultrasound (US) guidance offers an alternative to fluoroscopy for C3 to C6 cervical medial branch blocks (CMBBs), its use at the C7 level has not been examined. We hypothesized that US, using a biplanar imaging technique, could provide a shorter performance time than conventional fluoroscopy for C7 CMBB. METHODS: Fifty patients undergoing C7 CMBB were randomized to fluoroscopy or US guidance. A 0.6-mL mixture of local anesthetic and radiographic contrast was injected in both groups. The primary outcome was performance time. Secondary outcomes included success rate, pain levels preblock and postblock, and incidences of aberrant spread and procedure-related complications. RESULTS: Compared to fluoroscopy, US guidance was associated with a shorter performance time (233.6 ± 80.4 vs 390.6 ± 142.4 seconds; P < 0.001) and fewer needle passes (2 vs 4; P < 0.001). However, both imaging modalities provided similar success rates (92%-96%). Furthermore, no intergroup differences were found in preblock and postblock pain scores. In the fluoroscopy group, intravascular and intra-articular spreads were seen in 20% and 4% of cases, respectively. In the US group, a blood vessel was visualized overlying the target area and successfully avoided during needle insertion in 40% of patients. No procedure-related complications occurred in either group. CONCLUSIONS: Ultrasound guidance using a biplanar approach provides a similar success rate to fluoroscopy for C7 CMBB. However, US is associated with improved efficiency (decreased performance time and fewer needle passes).

Efficacy of the Greater Occipital Nerve Block for Cervicogenic Headache: Comparing Classical and Subcompartmental Techniques.

AIM: The aim of the study was to compare the efficacy of the greater occipital nerve (GON) block using the classical technique and different volumes of injectate with the subcompartmental technique for the treatment of cervicogenic headache (CH). METHODS: Thirty patients acted as his/her own control. All patients were submitted to the GON block by the classical technique with 10 mg dexamethasone, plus 40 mg lidocaine (5 mL volume). Patients were randomly allocated into 1 of 3 groups (n = 10) when pain VAS was > 3 cm. Each group was submitted to a GON subcompartmental technique (10 mg dexamethasone + 40 mg lidocaine + nonionic iodine contrast + saline) under fluoroscopy using either 5, 10, or 15 mL final volume. Analgesia and quality of life were evaluated. RESULTS: The classical GON technique resulted in 2 weeks of analgesia and less rescue analgesic consumption, compared to 24 weeks after the subcompartmental technique (P < 0.01). Quality of life improved at 2 and 24 weeks after the classical and the suboccipital techniques, respectively (P < 0.05). The data revealed that groups were similar regarding analgesia when compared to volume of injection (P > 0.05). CONCLUSIONS: While the classical technique for GON block resulted in only 2 weeks of analgesia, the subcompartmental technique resulted in at least 24 weeks of analgesia, being 5 mL volume sufficient for the performance of the block under fluoroscopy.

A comparison of ultrasound-guided and landmark-based approaches to saphenous nerve blockade: a prospective, controlled, blinded, crossover trial.

BACKGROUND: Blockade of the saphenous nerve is often used for surgeries below the knee. Depending on the approach, success rates vary widely ranging from 33% to 88%. In this prospective volunteer study, we compared 2 ultrasound-guided techniques, the modified vastus medialis and perifemoral saphenous nerve block with a below the knee field block. METHODS: Twenty volunteer adults, in a single-blinded, crossover, prospective trial underwent 3 different saphenous nerve blocks. The primary end point of block success was loss of sensation in the distal two-thirds distribution of the saphenous nerve. Secondary variables included time to perform the block, time to sensory loss, pain during block, and motor weakness. RESULTS: Compared with the below the knee field block success rate (30%), both the modified vastus medialis and perifemoral techniques had significantly higher success rates (80%, difference 50% with confidence interval [CI], 23%-77%, P = 0.009, and 100%, difference 70% with CI, 41%-91%, P < 0.001, respectively). However, the difference when comparing the perifemoral ultrasound technique against the modified vastus medialis ultrasound technique did not show significance (difference 20% with CI, -7% to 49%, P = 0.125). Also, no statistical differences were found with the other variables measured, except the perifemoral technique showed faster block performance times than below the knee field block (P = 0.007). CONCLUSION: In our prospective study, we have demonstrated that ultrasound-guided above the knee saphenous nerve blocks have higher success rates than a below the knee field block and are easily performed in a short amount of time.

Hand motion analysis using the imperial college surgical assessment device: validation of a novel and objective performance measure in ultrasound-guided peripheral nerve blockade.

BACKGROUND AND OBJECTIVES: The Imperial College Surgical Assessment Device (ICSAD) has been validated in various settings as an objective tool to measure technical performance. We sought to establish (1) the construct validity of the ICSAD as an assessment tool in ultrasound-guided supraclavicular block by determining its ability to discriminate between operators of different experience level and (2) the concurrent validity of the ICSAD by correlating it with a task-specific checklist and a global rating scale. METHODS: We compared 30 performances of ultrasound-guided supraclavicular block by junior residents with 30 performances by highly experienced consultant anesthesiologists. We also studied 10 anesthesiologists undertaking a 1-year regional anesthesia fellowship and compared a performance in their first month to one in their last 3 months. We used the ICSAD to measure 3 dexterity parameters during the scanning and needling phases of each block: time taken, number of movements, and path length traveled by each hand. Two blinded expert observers evaluated video recordings of each block using a 30-item task-specific checklist and a 7-item global rating scale. RESULTS: Consultants (experts) performed significantly better than residents (novices) on all ICSAD parameters in both scanning and needling phases. Fellows demonstrated improvement in all ICSAD parameters between their early and late performance, reflecting their transition from novice to expert. The task-specific checklist and global rating scale were also highly discriminating between novice and expert performances. There was excellent correlation between all 3 measurement tools, thereby establishing their concurrent validity. CONCLUSIONS: The ICSAD is both valid and useful in assessing performance of ultrasound-guided supraclavicular block.

Percutaneous electrode guidance using the insulated needle for prelocation of peripheral nerves during axillary plexus blocks.

BACKGROUND AND OBJECTIVES: Short reports have noted that percutaneous prelocation is helpful in determining the anatomic course of a peripheral nerve, and, thereby, may serve as a guide for block needle insertion. We prospectively studied percutaneous electrode guidance to assist axillary brachial plexus blocks. METHODS: In 131 consecutive patients, the tip of an insulated needle emitting 5 mA was placed on the skin above and below the axillary artery to obtain a hand motor response characteristic of the median, ulnar, and radial nerves in succession. The current was reduced until all movement had ceased. The needle was then inserted toward the nerve to be blocked, decreasing the intensity from 2 mA to 0.5 mA, so that the same selected motor response was still obtained. The length of the needle inserted was noted, and 1.5% lidocaine was injected. Pain verbal analogic score (VAS) values were noted during both procedures. Complete sensory blockade was evaluated at 30 min. RESULTS: Rates of successful percutaneous electrode guidance were 94.6% for the median nerve, 89.4% for the radial nerve, 88.5% for the ulnar nerve, and 85.5% for all 3 nerves together. A significant correlation was found between the lowest percutaneous current applied and the depth of the nerve stimulated at 0.5 mA. Pain VAS values were significantly lower during percutaneous stimulation than during needle insertion (P <.05). Sensory block for all 3 nerves was noted in 92% of patients. CONCLUSIONS: Percutaneous electrode guidance using the insulated needle enabled clinicians to locate the terminal branches of the plexus in the axilla and appreciate their depth. This method could, therefore, minimize patient discomfort and perhaps the risk of nerve trauma.

Sympathetic nervous system and pain: a clinical reappraisal.

The target article discusses various aspects of the relationship between the sympathetic system and pain. To this end, the patients under study are divided into three groups. In the first group, called "reflex sympathetic dystrophy" (RSD), the syndrome can be characterized by a triad of autonomic, motor, and sensory symptoms, which occur in a distally generalized distribution. The pain is typically felt deeply and diffusely, has an orthostatic component, and is suppressed by the ischemia test. Under those circumstances, the pain is likely to respond to sympatholytic interventions. In a second group, called "sympathetically maintained pain" (SMP) syndrome, the principal symptoms are spontaneous pain, which is felt superficially and has no orthostatic component, and allodynia. These symptoms, typically confined to the zone of a lesioned nerve, may also be relieved by sympathetic blocks. Since the characteristics of the pain differ between RSD and SMP, the underlying kind of sympathetic-sensory coupling may also vary between these cases. A very small third group of patients exhibits symptoms of both RSD and SMP. The dependence or independence of pain on sympathetic function reported in most published studies seems to be questionable because the degree of technical success of the block remains uncertain. Therefore, pain should not be reported as sympathetic function independent until the criteria for a complete sympathetic block have been established and satisfied.

The ultrasonic localization of retrobulbar needles during retrobulbar block.

PURPOSE: The tips of retrobulbar needles were visualized during retrobulbar block using ultrasound. The purpose of this study is to see how often the needle tip was located 5 mm behind the hind surface of the globe. METHODS: Twenty-five patients ranging in age from 22 to 84 years were studied after written informed consent was obtained. An ultrasonic photograph was taken before needle placement, with the needle in the proper position, and after local anesthetic had been injected. RESULTS: In none of the 25 patients studied was the needle tip at the 5-mm mark behind the eye. Placement ranged from 0.2 to 3.3 mm behind the globe. In 14 to 25 placements, the needle shaft was seen actually to indent the globe. The optic nerve was seen to be at least 9 mm from the needle tip in 6 of 25 patients. CONCLUSION: This study demonstrates that retrobulbar needle tips are closer to the globe than thought previously. A false sense of security may occur when performing retrobulbar blocks using only anatomic landmarks.

Bilateral burning foot pain: monitoring of pain, sensation, and autonomic function during successful treatment with sympathetic blockade.

We describe a patient with burning pain in both feet associated with local autonomic disturbances following bilateral traumatic sciatic mononeuropathies. The diagnosis of a sympathetically maintained pain was confirmed through a prompt response to sympathetic blockade. Although a mild alcohol-nutritional neuropathy was found, the clinical findings strongly suggested a diagnosis of bilateral causalgia. Clinical evaluation and quantitative sensory testing were performed prior to and after successive unilateral lumbar sympathetic nerve blocks. After unilateral blockade, bilateral improvement was recorded in measures of pain, sudomotor function, and foot temperature. Other measures of autonomic function showed variable responses to sympathetic blockade. Quantitative sensory testing revealed a dramatic alteration in the contralateral limb's thermal sense following unilateral block. This case underscores the potential for bilateral causalgia and provides additional evidence for a central mechanism operating in this disorder. The relationship between bilateral causalgia and the "burning feet syndrome" in alcoholic neuropathy is discussed.