Ultrasound-guided Lumbar Plexus Block Research Articles

An alternative of ultrasound-guided lumbar plexus block: a vertebral arch root method.

An alternative of ultrasound-guided lumbar plexus block: a vertebral arch root method.

Effects of ultrasound-guided lumbar plexus and sacral plexus block combined with general anesthesia on the anesthetic efficacy and surgical outcomes in elderly patients undergoing intertrochanteric fracture surgery: a randomized controlled trial

BackgroundSurgery for intertrochanteric fractures in elderly patients is challenging due to the risk of severe pain and significant stress responses. We investigated the effects of a combined approach of ultrasound-guided lumbar plexus and sacral plexus block with general anesthesia on anesthetic efficacy and surgical outcomes in these patients.MethodsA randomized controlled trial was conducted involving 150 elderly patients, divided into two groups: the combined anesthesia group (receiving ultrasound-guided lumbar plexus and sacral plexus block along with general anesthesia) and the general anesthesia alone group. Outcome measures included hemodynamic parameters, postoperative pain levels (VAS scores), postoperative recovery times, and incidence of adverse reactions.ResultsIn the combined anesthesia group, the patients had more stable intraoperative hemodynamics, lower postoperative VAS scores at 1, 3, and 6 h, and faster recovery times (eye-opening upon command and return of respiratory function) compared to the general anesthesia group. Furthermore, the incidence of adverse reactions was significantly lower in the combined anesthesia group.ConclusionsUltrasound-guided lumbar plexus and sacral plexus block combined with general anesthesia enhanced the anesthetic efficacy and improved surgical outcomes in elderly patients undergoing intertrochanteric fracture surgery.

Novel lumbar plexus block versus femoral nerve block for analgesia and motor recovery after total knee arthroplasty.

This study aimed to compare the postoperative analgesic efficacy and motor recovery of a novel lumbar plexus block (LPB) with that of a femoral nerve block (FNB) after total knee arthroplasty (TKA). Forty patients who underwent TKA were randomised equally into an lumbar plexus and sciatic nerve (LS) group (receiving novel LPB) and an femoral and sciatic nerves (FS) group (receiving FNB). The assessed variables were the onset time of pain, time to the first analgesic request, pain scores, motor block at 6, 12, and 24 h after TKA, and the number of patients receiving successful blockade for each branch of the lumbar plexus. In the LS group, the femoral, lateral femoral cutaneous, genitofemoral, iliohypogastric, ilioinguinal, and obturator nerves were blocked in 18, 20, 16, 18, 15, and 19 patients. Compared to the FS group, the LS group had a significantly shorter onset time of pain and time to the first analgesic request, a significantly larger total postoperative dose of sufentanil, significantly higher numeric rating scale scores for both rest and dynamic pain at 6, 12, and 24 h, and faster motor recovery. Novel ultrasound-guided LPB has a high blocking success rate and provides inferior postoperative analgesia, but faster motor recovery after TKA than FNB.

The anesthetic efficacy of ultrasound-guided lumbar plexus combined with quadratus lumborum block with Shamrock approach in total hip arthroplasty: study protocol for a randomized controlled trial

IntroductionThe lumbar plexus originates from multiple segments of the spinal cord. Both single-level lumbar plexus block (LPB) and transmuscular quadratus lumborum block (TQLB) are commonly used to provide analgesia for the patients undergoing total hip arthroplasty (THA). However, neither of them can completely cover the lumbar plexus. Multiple-level LPB is also not recommended since this expert technique involves more potential risks. To achieve a better anesthetic effect and avoid risks, we propose to combine ultrasound-guided LPB with TQLB with Shamrock approach. We aim to assess the anesthetic efficacy of this combination technique and expect it will be an ideal alternative for conventional LPBs in THA.Methods and analysisIn this prospective randomized controlled trial, 84 patients schedule for THA will be enrolled. The patients will be randomly assigned at a 1:1:1 ratio to receive LPB at L3 level (P group), T12 paravertebral block combined with LPB at L3 and L4 levels (TP group), or LPB combined with TQLB at L3 level (PQ group). Each method will be evaluated in terms of the successful rate of sensory blockade, postoperative pain, performance time of block, requirement for intraoperative sufentanil, cumulative doses of intraoperative vasoactive medications, and adverse events.Ethics and disseminationThe study protocol has been approved by the institutional review board (IRB) at Shanghai Jiao Tong University Affiliated Sixth People’s Hospital, China (No.2020–031). The results will be disseminated in a peer-reviewed journal and the ClinicalTrials.gov registry.Trial registrationClinicalTrials.gov, NCT04266236. Registered on 10 February 2020. ClinicalTrials.gov PRS: Record Summary NCT04266236.

A new approach for ultrasound-guided lumbar plexus block: ultrasound-guided paravertebral LPB.

A new approach for ultrasound-guided lumbar plexus block: ultrasound-guided paravertebral LPB.

Ultrasound-guided lumbar plexus block versus transversus abdominis plane block for analgesia in children with hip dislocation: A double-blind, randomized trial.

Lumbar plexus block is often used as analgesia for adult hip surgery, but it is rarely used in pediatric patients. This study aimed to compare the efficacy and feasibility of ultrasound-guided lumbar plexus block versus transversus abdominis plane block for postoperative analgesia in children with hip dislocation. Eighty children undergoing unilateral hip dislocation surgeries at our hospital from October 2019 to February 2021 were randomized to the lumbar plexus block group (group L) and transversus abdominis plane block group (group T). Compared with group L, the regional block time in group T was lower (8.0 ± 2.5 vs 11.5 ± 2.3 min, P < 0.05), and the ultrasound image definition was better (P < 0.05). There were no significant differences in mean blood pressure and heart rate within 24 h (all P > 0.05). Children's Hospital of Eastern Ontario Pain Scale scores were lower in group L than in group T at 18-24 h only (all P < 0.05). The satisfying analgesia rate in group L was higher than in group T (87.5 vs 65%, P < 0.05). No regional block-related complications were found in both groups. Ultrasound-guided lumbar plexus block showed a longer postoperative analgesic effect in children with hip dislocation compared with transversus abdominis plane block.

Comparative efficacy analysis of ultrasound-guided quadratus lumborum block and lumbar plexus block in hip arthroscopy: a pilot prospective randomized controlled trial.

ABSTRACTControlled trials assessing quadratus lumborum block (QLB) for post-operative analgesia in hip surgery are scarce. This study aimed to compare ultrasound-guided QLB and lumbar plexus block (LPB) for clinical efficacy in hip arthroscopy. Patients undergoing hip arthroscopy in Beijing Jishuitan Hospital in January–June 2019 were randomized to the lumbar plexus (L) and quadratus lumborum (Q) groups (n = 25/group). After either ultrasound-guided block for 30 min, both groups were prepared for surgery after muscle strength measurement in the affected limbs. Opioid doses for patient-controlled analgesia (PCA), visual analog scale (VAS) scores in the resting and active states, upon leaving the post-anesthesia care unit (PACU), and at 2–48 h post-surgery were recorded, and post-operative complications were also recorded. Muscle strength in the affected limbs was significantly higher in the Q group compared with the L group (4.0 versus 2.0, P < 0.001). VAS scores were similar in both groups post-surgery (P > 0.05). One patient had epidural spread in the L group, with no other complications. Compared with ultrasound-guided LPB, ultrasound-guided QLB provides similar and good post-operative analgesia after hip arthroscopy, with less impact on muscle strength and fewer complications. These results should be confirmed in larger trials.

A comparative study between magnesium sulfate and dexmedetomidine as adjuvants to bupivacaine using ultrasound-guided lumbar-plexus block in lower abdominal surgeries

Background and aim Pain international association of described pain as an unpleasant sensory and emotional practice accompanied with actual or potential tissue injuries. Opioid administrations remain the cornerstone of postoperative pain relief, but it may cause significant side effects, including sedations, nausea, vomiting, and urinary retention. We aimed to compare the efficacy of ultrasound-guided lumbar-plexus block through adding magnesium sulfate and dexmedetomidine (DEX) to bupivacaine on postoperative analgesia and thereafter surgical operation. Patients and methods This prospective, randomized, double-blinded, controlled research was performed on Al-Azhar University Hospitals. A total of 75 cases of both sexes, age between 21 and 65 years, American Society of Anesthesiologists class I– II, were listed for elective lower-abdomen surgical operation underneath general anesthesia. Results Pain scores were decreased significantly in the study groups for 12 and 18 h in BM and BD, respectively, also, there was a significant decrease at 2, 4, 6, 8, and 12 h in the BD group lesser than the BM group postoperatively. The time to the initial analgesic appeal was significantly extended in the BD group (11.9±1 h) than the BM group (10.6±0.7 h). Conclusion Posterior lumbar-plexus block utilizing 22 ml of bupivacaine 0.5% with DEX 1 μg/kg decreases pain score, opioid consumption, prolongs duration of analgesia, better hemodynamics stability, and perfect outcome of cases’ satisfaction postoperatively compared with posterior lumbar-plexus block using 22 ml of bupivacaine 0.5% with magnesium sulfate 150 mg. DEX provides faster onset time and longer periods of MB and extended period of analgesia with smaller consumptions of postoperative rescue analgesia.

Continuous Lumbar Plexus Block under the Guidance of the "Shamrock Method" Ultrasound: Analgesic Effects and Hemodynamic Effects after Total Knee Arthroplasty in Elderly Patients.

Objective To explore the effect of continuous lumbar plexus block guided by the “Shamrock method” on postoperative analgesia and hemodynamics in elderly patients after total knee arthroplasty (TKA). Methods From January 2020 to December 2020 in our hospital, 98 patients who underwent TKA were selected. Using the random number table method, the patients were divided into two groups: a continuous lumbar plexus block group (group L), with 49 patients, and a continuous femoral nerve block group (group F), with 49 patients. The onset time and maintenance time of motor and sensory nerve blocks in patients were recorded. A visual analogue scale (VAS) was applied to assess the pain severity at 6, 12, 24, and 48 h after the operation. The VAS score (FVAS) was applied to evaluate the pain severity of the patients during 24 and 48 h after the operation and knee joint functional exercise. The levels of hemodynamic indexes such as heart rate, mean arterial pressure, and oxyhemoglobin saturation and the levels of hemorheological indexes such as plasma viscosity, high and low whole blood shear viscosity, fibrinogen, and hematocrit were detected and compared between the two groups immediately after the operation and at 12 h and 48 h after the operation, respectively. The incidence of adverse reactions induced by anesthesia was counted. Results The onset time of motor and sensory nerve blocks in group L was lower than that in group F, and the maintenance time was higher than that in group F (P < 0.05). The VAS scores of 6, 12, 24, and 48 h after operation in group L were significantly lower than those in group F (P < 0.05). The FVAS scores of group L at 24 and 48 h after operation were significantly lower than those of group F (P < 0.05). The heart rates of the patients in the two groups were higher at 12 h and 48 h after operation than those immediately after operation (P < 0.05). The heart rates at 12 h and 48 h after operation in group L were lower than those in group F (P < 0.05). The plasma viscosity, high whole blood shear viscosity, and low whole blood shear viscosity in the group L at 12 h and 48 h after operation were lower than those in group F (P < 0.05). There was no significant difference in the incidence of local anesthetic poisoning, nausea, vomiting, urinary retention, pruritus, and other adverse reactions between the two groups (P > 0.05). Conclusion The “Shamrock method” ultrasound-guided continuous lumbar plexus block in elderly patients after TKA has good analgesic effect, stable hemodynamics, little influence on hemorheology, and good safety. It is of great value to enhance the surgical effect and promote postoperative rehabilitation.

MATrix LABoratory Algorithm in Ultrasound Image-Guided General Drug Anesthesia along with Lumbar and Sacral Plexus Block in Hip Replacement under

Objective. The study aimed to explore the application of ultrasound image-guided general drug anesthesia combined with lumbar and sacral plexus block based on MATrix LABoratory (MATLAB) algorithm in hip arthroplasty and to study its clinical effect. Methods. The classic geodesic active contour (GAC) algorithm and the improved fuzzy clustering level set algorithm were used to segment ultrasound images of waist plexus, and then their segmentation effects were compared. Both algorithms are from the MATrix LABoratory (MATLAB) platform. A total of 60 patients undergoing hip arthroplasty were selected and randomly enrolled into control and experimental groups. The control group accepted general drug anesthesia, and the experimental group accepted ultrasound-guided lumbar and sacral plexus block combined with general anesthesia. The mean arterial pressure and heart rate at t0 (before anesthesia), t1 (before ventilation), t2 (when the skin was incised), t3 (when the prosthesis was implanted), t4 (when the incision was closed), and t5 (at the end of ventilation) were observed, and the intraoperative sufentanil dosage and 24 h analgesic dosage, the incidence of postoperative delirium, and the incidence of cognitive dysfunction were recorded. Results. The improved fuzzy clustering level set algorithm was better than the GAC model algorithm in image segmentation and running time. In contrast with the control group, the average arterial pressure and heart rate of the experimental group at the four time points of t1, t2, t3, and t5 were obviously reduced ( P &lt; 0.05). In contrast with the control group, the amount of sufentanil and analgesics in the experimental group was obviously reduced ( P &lt; 0.05), and the incidence of postoperative cognitive dysfunction and delirium was obviously reduced ( P &lt; 0.05). Conclusion. The improved fuzzy clustering level set algorithm is superior to the GAC model in image segmentation and running time. Under its guidance, the lumbar and sacral plexus block combined with general anesthesia has a good clinical effect in hip arthroplasty, which is better than simple general anesthesia.

Flow dynamics of ultrasound-guided lumbar plexus block in adults.

Background and Aims:The outcomes of plexus and peripheral nerve blocks depend on needle-nerve contact and the spread of local anesthetic (LA) around the plexus or nerve. Needle-nerve distance and spread of LA could be visualized during US-guided lumbar plexus block (LPB).Material and Methods:After Institutional Ethics Committee approval and after obtaining informed consent, 24 American Society of Anesthesiologists’-physical status I–III patients who underwent surgical fixation of fractures of proximal femur were enrolled. Spinal anesthesia was a primary anesthetic in all patients. At the end of the surgery, all patients received US and neurostimulation-aided LPB at the third lumbar nerve root (LNr). The primary aim was to determine the spread of LA in the lumbar plexus area with the relation of the needle tip and LNr contact. The secondary aim was to understand block efficacy in terms of pain scores monitored at regular intervals and 100 mg intravenous tramadol was administered as a rescue analgesic if VAS >4.Results:In all 24 patients, we observed an oval and antegrade LA spread after lumbar plexus was identified with neurostimulation at L3. With the needle closer to intervertebral foramina (IVF), a retrograde spread was visualized. Only 2/24 patients received rescue analgesia in the first 24 h.Conclusion:The type of spread after the US-guided LPB could predict block success of block and a possible epidural spread.

Intricacies of Ultrasound-guided Lumbar Plexus Block in Octogenarians: A Retrospective Case Series.

Background:Ultrasound (US)-guided lumbar plexus block (LPB) could be technically challenging in elderly patients. The lumbar paravertebral sonoanatomy is undescribed in the elderly. In an attempt to understand the relevant sonoanatomy, identify the lumbar plexus elements, and understand the difficulties that encountered while performing LPB in elderly patients, we retrospectively analyzed US of 23 elderly patients who were administered US-guided LPBs.Methods:After institutional ethics committee approval, we retrospectively reviewed stored US images of lumbar paravertebral sonoanatomy in 23 elderly patients and analyzed psoas major muscle, lumbar vertebral body, lumbar nerve, and lumbar artery.Results:On US examination, features of psoas major muscle, lumbar vertebral body, lumbar nerve, and lumbar artery were noted and analyzed.Conclusion:US-guided visualization of the components of the lumbar paravertebral area is difficult and inconsistent in the elderly. Therefore, we suggest performing a scout scan, identify the structures, and use neurostimulation all the time for performing LPB in these patients.

Ultrasound-guided anterior iliopsoas muscle space block versus posterior lumbar plexus block in hip surgery in the elderly: A randomised controlled trial.

Ultrasound-guided posterior lumbar plexus block is widely used for hip fracture surgery but it requires a change of position, which may be painful. Our primary objective was to describe a new technique, the anterior iliopsoas muscle space block, which can be performed in the supine position, and to test the hypothesis that its analgesia for hip surgery was similar to that of the traditional posterior lumbar plexus block. Randomised, double-blind study. Shanghai 6th People's Hospital, China, from February to August 2019. Forty-eight patients scheduled for unilateral hip fracture surgery were included in the study. The exclusion criteria were infection at the puncture site, history of hip surgery, pre-existing neurological deficits of the lower extremity, contraindications for regional anaesthesia, allergy to local anaesthetics, coagulopathy, abuse of medicine or alcohol, or daily consumption of analgesics. Patients were randomised to receive a lateral sacral plexus block with either an anterior iliopsoas muscle space block or a posterior lumbar plexus block, using 0.33% ropivacaine (30 ml each). The main outcome was verbal numerical scale (VNS) pain intensity 1 h after surgery in the postanesthesia care unit, and the secondary outcome was the dose of intra-operative fentanyl. The differences in VNS scores and fentanyl use between the groups were analysed. Based on previous work, we considered a difference (confidence interval [CI]) of 1.6 on the VNS to be significant. The median [IQR] pain scores in postanesthesia care unit were similar in the anterior 0 [0 to 3] and posterior groups 1.5 [0 to 3]. The median scores for intra-operative fentanyl use were similar in the anterior 20 [10 to 42.5] μg and posterior groups 15 [0 to 50] μg (P = 0.34). The difference in the median pain score at-rest was NS: anterior group 0.5 [0 to 5], posterior group 0 [0 to 2], median difference -0.5 (95% CI -2 to 0). The median post to preblock difference in VNS was higher in the anterior -0.5 [-2 to 0] than in the posterior group 0 [-1.25 to 0], median difference 0.5 (95% CI 0 to 1). The median block onset time was longer in the anterior 11 [6 to 14.25] min than in the posterior group 6 [4.75 to 8] min (P = 0.002), median difference -5 (95% CI -7 to -1). The anterior iliopsoas muscle space block had the same effect as the posterior lumbar plexus block on peri-operative analgesia for hip surgery, but with a longer onset time. Therefore, anterior iliopsoas muscle space block can be recommended as a routine technique for hip and lower limb procedures. http://www.chictr.org.cn identifier: ChiCTR1900021214.

A Randomized Study Comparing the Efficacy of Ultrasound Guided Lumbar Plexus Block and Epidural Anesthesia for Postoperative Analgesia in Patients Undergoing Total Hip Replacement.

Patients undergoing total hip replacement (THR) experience severe postoperative pain. The advantage of pain relief by continuous epidural anesthesia (CEA) is offset by various adverse effects. Ultrasound guided (USG) continuous lumbar plexus block (LPB) has emerged as an alternative approach for postoperative analgesia in patients undergoing THR, especially where epidural is difficult or contraindicated. This randomized controlled trial compared USG-LPB with CEA for postoperative pain relief until 48 hours in patients undergoing THR, with 0.5% ropivacaine (15 mL) used as boluses for both CEA and LPB. The mean time to the first bolus was 380.60 ± 77.66 min in the LPB group whereas it was 307.40 ± 83.60 min in the epidural group (P = 0.002). Thus, patients in the LPB group took more than one hour longer than the epidural group to take their first bolus, which is clinically meaningful besides being statistically significant. The pain score on movement was also significantly lower, and patient satisfaction higher, in the LPB group. There were no significant intergroup differences about motor power, pain at rest, total ropivacaine consumption, and adverse effects. USG-LPB is an effective alternative to CEA combined with general anesthesia for postoperative analgesia after THR.

Lumbar plexus block versus suprainguinal fascia iliaca block for total hip arthroplasty: A single-blinded, randomized trial

Study objectiveComparison of ultrasound-guided lumbar plexus block (LPB) and suprainguinal fascia iliaca block (SIFIB) in patients undergoing total hip arthroplasty (THA). DesignRandomized equivalence trial. SettingUniversity Hospital. PatientsSixty patients undergoing primary THA. InterventionsPatients were randomly allocated to receive ultrasound-guided LPB (n = 30) or SIFIB (n = 30). The local anesthetic agent (40 mL of levobupivacaine 0.25% with epinephrine 5 μg/mL) and block adjuvant (4 mg of intravenous dexamethasone) were identical in all subjects. Postoperatively, all patients received patient-controlled intravenous analgesia (morphine) as well as acetaminophen and ketoprofen during 48 h. MeasurementsA blinded investigator recorded morphine consumption at 24 and 48 h as well as time to first morphine request, pain scores at 3, 6, 12, 24 and 48 h, incidence of adverse events, time to readiness for discharge, and length of hospital stay. The blinded investigator also carried out sensorimotor block assessment at 3, 6 and 24 h using a 10-point sensorimotor composite scale. Main resultsNo intergroup differences were found in terms of cumulative morphine consumption at 24 h (95% CI: −4.0 mg to 2.0 mg) and 48 h (95% CI, −5.0 mg to 2.0 mg) or time to first morphine request. Furthermore, pain scores were similar at all time intervals after 3 h. There were no intergroup differences in terms of composite sensorimotor scores at 3 and 6 h. However, SIFIB lasted longer than lumbar plexus block as evidenced by a higher composite score at 24 h. No intergroup differences were found in terms of complications. Compared with LPB, SIFIB was associated with shorter time to readiness for discharge (3 [1-4] vs. 2 [1-3] days; P = 0.042) and length of hospital stay (3 [2-5] vs. 3 [2-4] days; P = 0.048). ConclusionsFor THA, no differences were found between LPB and SIFIB in terms of breakthrough morphine requirement and pain control. However, SIFIB resulted in a longer block and was associated with shorter time to readiness for discharge as well as decreased hospital stay.

The effect of needle tip tracking on procedural time of ultrasound-guided lumbar plexus block: a randomised controlled trial.

Technology that facilitates performance of deep peripheral nerve blocks is of clinical interest. The Onvision™ is a new device for ultrasonographic needle tip tracking that incorporates an ultrasound sensor on the needle tip that is then represented by a green circle on the ultrasound screen. The primary aim of this study was to investigate the effect of needle tip tracking on procedural time in the first human volunteer study. Secondary outcome measures included: number of hand movements; hand movement path length; block success rate; block onset time; block duration; discomfort experienced by the volunteers; and the anaesthetists' confidence as to whether their block would be successful. Two anaesthetists performed ultrasound-guided lumbar plexus blocks with an out-of-plane technique, with and without the use of needle tip tracking. In total, data from 25 volunteers were studied. Mean (SD) procedural time was 163 (103) s with needle tip tracking and 216 (117) s without (p=0.10). Hand motion analysis showed that needle tip tracking was associated with a significant decrease in the mean (SD) number of intended needling hand movements (39 (29) vs. 59 (36); p=0.03) and path lengths (3.2 (3.1)m vs. 5.5 (4.5)m; p=0.03). No differences were found for any other secondary outcomes. The use of Onvision needle tip tracking did not reduce procedural time for out-of-plane ultrasound-guided lumbar plexus block but did reduce the number of hand movements and path lengths. This may indicate improved needle control but further studies are needed to confirm this finding.

Comparison of combined lumbar and sacral plexus block with sedation versus general anaesthesia on postoperative outcomes in elderly patients undergoing hip fracture surgery (CLSB-HIPELD): study protocol for a prospective, multicentre, randomised controlled trial

IntroductionHip fracture in elderly people is a global public health problem, with substantial associated mortality and disability. Nearly all patients with hip fracture undergo surgical treatment, but optimal anaesthesia for...

Effect of ultrasound-guided lumbar plexus block on emergence agitation in children undergoing hip surgery: study protocol for a randomized controlled trial

BackgroundEmergence agitation (EA) is a common postoperative issue in children that causes self-injury, increases stress on healthcare team members, and even leads to postoperative maladaptive behavioral changes in children. Clear answers regarding a ‘gold standard’ for prevention of EA are not available. Pain is regarded as an important causative factor of EA, and ultrasound-guided lumbar plexus block is a safe and efficient anesthetic method that can provide satisfactory pain relief in pediatric hip surgery. The purpose of our study is to determine whether ultrasound-guided lumbar plexus block can reduce the incidence of EA in children undergoing hip surgery.Methods/designWe designed a prospective, randomized, controlled, blinded trial to determine the effect of ultrasound-guided lumbar plexus block on EA. A total of 100 American Society of Anesthesiologists class I–II children (1–6 years old) scheduled for elective hip surgery will be recruited for this study. Participants will be randomized at a 1:1 ratio to receive either ultrasound-guided lumbar plexus block or fentanyl after the induction of general anesthesia. The primary outcome is the incidence of EA 30 min after emergence from anesthesia using the Pediatric Anesthesia Emergence Delirium (PAED) score. The secondary outcomes are the severity and duration of EA 30 min after emergence from anesthesia using the PAED score, postoperative pain evaluated by the Children’s Hospital of Eastern Ontario Pain Scale, and the incidence of postoperative adverse events. Randomization will be conducted using a computer-generated randomization schedule. Outcome assessors and data collectors will be blinded to the group allocations. Assessments will be performed before surgery, intraoperatively, and postoperatively at every time point.DiscussionOur hypothesis in this trial is that ultrasound-guided lumbar plexus block can decrease the incidence of EA in children undergoing elective hip surgery. This trial will provide clinical answers to verify our hypothesis. If our hypothesis is confirmed, the results could provide a safe method to prevent EA.Trial registrationChinese Clinical Trial Registry, ChiCTR-INR-17011525. Registered on 30 May 2017.

Efficacy of "over iliac crest method" for ultrasound-guided posterior lumbar plexus block: a comparison with manual palpation and sagittal positioning

Objective To evaluate the efficacy of over iliac crest for ultrasound-guided posterior lumbar plexus block by comparing with manual palpation and sagittal positioning. Methods A total of 75 patients, aged 25-64 yr, weighing 42-90 kg, with body mass index of 17-32 kg/cm2, of American Society of Anesthesiologists physical status Ⅰ-Ⅲ, scheduled for elective lower extremity surgery under ultrasound-guided posterior lumbar plexus block combined with parasacral sciatic nerve block, were divided into 3 groups (n=25 each) using a random number table method: manual palpation group (group M), sagittal positioning group (group S) and over iliac crest group (group O). Patients received ultrasound-guided posterior lumbar plexus block with in-plane technique using the corresponding positioning method in M, S and O groups.Successful blockade of each level was recorded at 30 min after injection.Time to determine the lumbar intervertebral space, puncture time for lumbar plexus block, the requirement for adjuvant drugs and block efficacy were recorded.The development of complications related to puncture and nerve block was also recorded. Results Compared with group M, the success rates of blockade at levels L1 and L2 were significantly increased, the success rates of blockade at levels L4 and L5 were decreased (P 0.05), the time to determine the lumbar intervertebral space was prolonged, and the requirement for adjuvant drugs was decreased during surgery in O and S groups, and the efficacy of block was significantly enhanced in group O (P 0.05). There was no significant difference in the puncture time for lumbar plexus block between the three groups (P>0.05). Complications related to puncture and nerve block were not found in three groups. Conclusion Over iliac crest provides higher success rate and better efficacy than manual palpation and sagittal positioning when used for lumbar plexus block. Key words: Lumbosacral plexus; Nerve block; Ilium

Ultrasound-guided Lumbar Plexus Block in Supine Position.

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