Single-injection Sciatic Nerve Block Research Articles

Peripheral Nerve Blockade for Medial Patellofemoral Ligament Reconstruction in Pediatric Patients: The Addition of a Proximal Single-Injection Sciatic Nerve Block Provides Improved Analgesia.

PurposeWe tested the hypothesis that the addition of a single-injection proximal sciatic nerve block to an adductor canal block would significantly reduce pain scores and opioid requirements compared to a group of patients that received only an adductor canal or femoral nerve block for medial patellofemoral ligament reconstruction in pediatric patients. The primary end-point is the number of patients achieving a Patient Acceptable Symptom State (PASS) (pain score less than four) for the entire 24-hour postoperative period in patients with and without a proximal sciatic block.Patients and MethodsThis is a retrospective cohort study of 144 consecutive pediatric patients, ages 10 to 18 years, undergoing medial patellofemoral ligament reconstruction with peripheral nerve blockade for postoperative analgesia from 2016–2020 at a pediatric orthopedics children’s hospital. Patients were divided into 2 cohorts with and without a proximal sciatic nerve block: group A/F: adductor canal or femoral CPNB and group AS: adductor canal CPNB and a proximal single-injection sciatic nerve block.ResultsThere was strong evidence for an increase in the number of patients who reported a pain score less than four for the entire 24-hour postoperative period in the group that received the additional proximal sciatic block. (PASS: A/F 13/62 (21%) vs AS 43/82 (52%), p<0.001) There was strong evidence for a reduction in mean and maximum pain scores and opioid requirements in the first 24-hours after surgery in the proximal sciatic group.ConclusionThe addition of a proximal sciatic nerve block was associated with significantly reduced mean and maximum pain scores and opioid requirements after medial patellofemoral ligament reconstruction in pediatric patients and supports a randomized clinical trial to confirm these findings. Based on the results of this study we recommend the addition of a proximal sciatic nerve block, anterior or posterior, to an adductor canal block to provide improved analgesia and reduced opioid requirements in the 24-hours after MPFLR in pediatric patients.

Continuous Versus Single-Injection Sciatic Nerve Block Added to Continuous Femoral Nerve Block for Analgesia After Total Knee Arthroplasty

The benefit of adding sciatic nerve block (SNB) to femoral nerve block to improve analgesia after total knee arthroplasty (TKA) is uncertain. We hypothesized that the effective duration of single-injection SNB is too short to improve postoperative analgesia and that this contributes to conflicting results on the efficacy of SNB after TKA. We evaluated this hypothesis in a prospective double-blind randomized controlled trial. Sixty patients undergoing TKA were randomly allocated to a continuous SNB group or a single-injection SNB group. All patients received femoral nerve block (0.5% ropivacaine 20 mL) and SNB (0.2% ropivacaine 20 mL) and catheters were inserted into both peripheral nerve block sites before surgery. Both groups received continuous femoral nerve block and patient-controlled intravenous analgesia with morphine. Continuous SNB (0.2% ropivacaine 5 mL/h; continuous SNB group) or sham continuous SNB (0.9% normal saline 5 mL/h; single-injection SNB group) was provided after surgery. The primary outcome was total morphine consumption for 48 hours after surgery. Total morphine consumption in the 48-hour period after surgery was significantly lower in the continuous SNB group compared with the single-injection SNB group [4.9 (5.9) vs 9.7 (9.5) mg, P = 0.002]. Visual analog scale pain scores at rest were also significantly lower in the continuous SNB group (P = 0.035). The combination of continuous femoral and SNB provides a superior opioid sparing effect and improves analgesia after TKA.

The Comparing of Ultrasound-guided Techniques: Sciatic Block with Continuous Lumbar Plexus Block or Continuous Femoral Nerve Block for Anesthesia and Analgesia of Total knee Replacement

Background and Aims: This double blind prospective randomized clinical trial evaluated the efficacy and safety of continuous ultrasound-guided lumbar plexus block compared to continuous ultrasound-guided femoral nerve block, in the intra-operative and postoperative periods after total knee replacement. Methods: Forty ASA I-III patients were randomized to receive: continuous femoral block (n= 20, 30 ml of ropivacaine 5 mg/ml) or continuous lumbar plexus block (n= 20, 30 ml of ropivacaine 5 mg/ml) both in association with single injection sciatic nerve block. All patients received continuous infusion of 2 mg/ml of ropivacaine at 8 ml/h for 48 hours and intravenous morphine for patient-controlled analgesia. Primary outcomes were intra-operative sufentanil consumption and verbal analogue scale (VAS) score at rest at 24h follow up. Results: Intra-operative sufentanil consumption was higher in the femoral block (FEM) group compared to the lumbar plexus block (PSOAS) group (FEM: 10.00 (10.00, 17.50) µg; PSOAS: 2.50 (0.00, 10.00) µg. p= 0.002). Obturator motor blockade occurred more frequently in the PSOAS group (70%) than in the FEM group (40%) (p=0.1); however, we found no differences in sensory blockade (p=0.6). VAS at rest was similar in the two groups at 24h postoperatively (FEM: 29.50 ± 14.74 mm; PSOAS: 25.60 ±17.42 mm. p=0.4), and throughout the follow-up period. No differences were detected in pain scores during physiotherapy. Conclusion: Continuous femoral and lumbar plexus blocks, both in association with sciatic nerve block, provided similar VAS scores at 24h, and throughout the follow-up period; intra-operative sufentanil consumption was, however, lower in the lumbar plexus block group.

The effect of stimulating versus conventional perineural catheters on postoperative analgesia following ultrasound-guided femoral nerve localization

Study Objective To test the hypothesis that, if the femoral nerve is correctly localized using ultrasound (US) guidance, the type of perineural catheter used has no effect on catheter success. Design Randomized controlled trial. Setting Post-anesthesia care unit of an academic teaching hospital. Patients 40 ASA physical status 1, 2, and 3 patients, ages 55-85 years, undergoing elective total knee arthroplasty. Interventions All patients received postoperative continuous femoral nerve blocks and a single injection sciatic nerve block. Nerve localization was accomplished using US guidance and electrical nerve stimulation so that the needle tip was visualized deep to the femoral nerve. Patients were randomized to receive either stimulating (Group SC) or nonstimulating catheters (Group NSC) in the usual manner for each device. Catheters were bolused with ropivacaine and an infusion commenced. Measurements The primary outcome was quality of analgesia (as measured by a numerical rating scale). Other outcomes included sensory block success rate, number of attempts and time required to localize the needle tip correctly, number of attempts and time required to place the perineural catheter, amount of local anesthetic and opioid use postoperatively, and degree of completion of preset postoperative rehabilitation goals. Main Results Quality of analgesia was similar at all time intervals. Rates of successful femoral block (95% vs 80%; P = 0.34) were similar between groups. Time required to position the catheter was greater in Group SC than Group NSC (3.45 ± 2.05 min vs 1.72 ± 0.88 min; P < 0.01). Conclusions Ultrasound guidance for needle localization prior to catheter insertion for femoral nerve block results in similar block characteristics between stimulating and nonstimulating catheters. The use of nonstimulating catheters avoids the technical challenges of stimulating catheters and does not require additional helpers.

Does Continuous Sciatic Nerve Block Improve Postoperative Analgesia and Early Rehabilitation After Total Knee Arthroplasty?

The aim of this prospective, randomized, double-blind study was to evaluate whether continuous sciatic nerve block can improve postoperative pain relief and early rehabilitation compared with single-injection sciatic nerve block in patients undergoing total knee arthroplasty (TKA) and lumbar plexus block. After ethical committee approval and written informed consent, 38 patients with ASA physical status I to II were enrolled. The first group received continuous sciatic and continuous lumbar plexus blocks (group regional or R, n = 19), whereas the second group received a single sciatic nerve block followed by saline infusion through the sciatic catheter and continuous lumbar plexus block (group control or C, n = 19). We assessed morphine consumption, scores for visual analog scale for pain at rest (VASr), and during continuous passive motion (VASi during CPM) for 48 hours postoperatively. Effectiveness of early ambulation was also evaluated. Scores for VASr and VASi during CPM, as well as morphine consumption, were significantly higher in group C than in group R (P < 0.01). Moreover, patients in group R showed earlier rehabilitation with more effective ambulation (P < 0.05). Continuous sciatic nerve block improves analgesia, decreases morphine request, and improves early rehabilitation compared with single-injection sciatic nerve block in patients undergoing TKA and lumbar plexus block.

Value of Single-Injection or Continuous Sciatic Nerve Block in Addition to a Continuous Femoral Nerve Block in Patients Undergoing Total Knee Arthroplasty

Continuous femoral nerve block in patients undergoing total knee arthroplasty (TKA) improves and shortens postoperative rehabilitation. The primary aim of this study was to investigate whether the addition of sciatic nerve block to continuous femoral nerve block will shorten the time-to-discharge readiness. Ninety patients undergoing TKA were prospectively randomized to 1 of 3 groups: patient-controlled analgesia via femoral nerve catheter alone (F group) or combined with a single-injection (Fs group) or continuous sciatic nerve block (FCS group) until the second postoperative day. Discharge readiness was defined as the ability to walk and climb stairs independently, average pain on a numerical rating scale at rest lower than 4, and no complications. In addition, knee function, pain, supplemental morphine requirement, local anesthetic consumption, and postoperative nausea and vomiting (PONV) were evaluated. Median time-to-discharge readiness was similar: F group, 4 days (range, 2-16 days); Fs group, 4 days (range, 2-7 days); and FCS group, 4 days (range, 2-9 days; P = 0.631). No significant differences were found regarding knee function, local anesthetic consumption, or postoperative nausea and vomiting. During the day of surgery, pain was moderate to severe in the F group, whereas Fs and FCS groups experienced minimal pain (P < 0.01). Patients in the F group required significantly more supplemental morphine on the day of surgery and the first postoperative day. Until the second postoperative day, pain was significantly less in the FCS group (P < 0.01). A single-injection or continuous sciatic nerve block in addition to a femoral nerve block did not influence time-to-discharge readiness. A single-injection sciatic nerve block can reduce severe pain on the day of the surgery, whereas a continuous sciatic nerve block reduces moderate pain during mobilization on the first 2 postoperative days.

Preoperative gabapentin in patients undergoing primary total knee arthroplasty

Patients undergoing total knee arthroplasty usually receive a multimodal analgesic regimen including peripheral nerve blockade, but may still experience significant pain. This study examined whether preoperative gabapentin decreases acute postoperative pain and opioid consumption in this setting. Retrospective chart review of single institution, hospital-based orthopaedic practice. Consecutive patients undergoing unilateral elective primary knee arthroplasty were evaluated for perioperative gabapentin use. Sixty-one consecutive patients received gabapentin; for each, an age- and gender-matched control was identified. Patients in both groups demonstrated similar demographics, all received lumbar plexus blockade. Catheters were removed on postoperative day 2 (95%). There were no differences in postoperative pain scores or opioid use between groups. Overall, median verbal pain scores (IQR) were 0(1), 0(3), 1(3) and 3(3) in the post-anaesthesia care unit and postoperative days 0, 1 and 2, respectively. Postoperative consumption of other analgesics was not different across groups. Patients in the gabapentin group received a single-injection sciatic nerve block less often than patients in the control group (77% vs. 94%, respectively; p < 0.05). Patients undergoing unilateral total knee arthroplasty experience low pain scores utilizing a multimodal analgesic regimen including continuous lumbar plexus blockade independent of gabapentin use.

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Single-Injection Femoral and Sciatic Nerve Blocks for Pain Control After Total Knee Arthroplasty

This study was designed to evaluate the addition of a single-injection sciatic nerve block to a femoral nerve block for analgesia after total knee arthroplasty. Fifty-seven patients undergoing primary total knee arthroplasty were randomized to receive femoral nerve blockade or a sham block. A subsequent 31 patients received both femoral and sciatic nerve blocks (FSNBs) before general anesthesia. Intravenous morphine use and visual analog pain scale scores were recorded at regular intervals. Femoral and sciatic nerve blocks were placed in less than five minutes, on average. Lower visual analog pain scale scores were noted in both femoral nerve blockade and FSNB groups compared to shams through 48 hours. Morphine use was significantly lower in the FSNB group. Femoral and sciatic nerve block can be placed quickly and consistently in the operating room with improved postoperative pain relief and reduced narcotic consumption.

Lateral or Posterior Popliteal Approach for Sciatic Nerve Block: Difference is Related to the Anatomy

In Response: We thank Risch et al. (1) and Palmisani et al. (2) for their comments on our article. In response to Risch et al., we clearly state that nerve stimulation of the sciatic nerve was performed 10 cm from the popliteal skin crease, after the recommendations made in the study of Vloka et al. (3) in cadavers. As Vloka et al. show, injection at this point ensures placement of the needle in the vicinity of, or proximal to, the separation of the sciatic nerve. Although Borgeat et al. (4) have found a high level of clinical efficacy in using the apex of the popliteal fossa as the injection site, we believe that anatomic confirmation should be sought from cadavers that this point corresponds to the division of the sciatic nerve. Our study (5) which compared a single- versus a double-injection technique, must be based on a reference point validated by anatomical observation. The time between the two injections in the double stimulation group is not recorded but the total performance time, which is provided, is low. In practice, when the first injection is completed, the second injection is begun immediately. Although it is true that multiple nerve stimulation theoretically has a greater risk of injury, in practice this has not been demonstrated (6). Despite the comments by Palmisani et al. (2) we believe that the single-injection technique is as successful using a posterior approach as a lateral approach. For example, Borgeat et al. (4) use only the posterior approach, in their study of 500 patients, and had a 94% success rate. The difference in efficacy in single injection between the studies of Borgeat et al. (4), Arcioni et al. (7), and our own may well be explained by the difference in dose. While we used 25 mL of mepivacaine 1%, Arcioni et al. used 30 mL of ropivacaine 0.75% and Borgeat et al. used 40–50 mL of ropivacaine 0.5%. The tibial response, plantar flexion or inversion, should be considered as the motor response of choice when a single injection sciatic nerve block in the popliteal fossa is performed. This is supported by the most recent clinical studies (8) and through the magnetic resonances of two volunteers in the study of Arcioni et al. (7). We believe that, as our study shows, the use of a double injection of the sciatic nerve has advantages when working with low doses. Xavier March, MD Olga Pineda, MD Dolores Caramés, MD Antonio Villalonga, PhD Servei d'Anestèsia Reanimació i Terapèutica del Dolor Hospital Universitari de Girona Dr Joseph Trueta Girona, Spain [email protected]

Nerve Stimulator-Assisted Evoked Motor Response Predicts the Latency and Success of a Single-Injection Sciatic Block

Variable onset latency of single-injection sciatic nerve block (SNB) may result from drug deposition insufficiently close to all components of the nerve. We hypothesized that this variability is caused by the needle tip position relative to neural components, which is objectified by the type of evoked motor response (EMR) elicited before local anesthetic injection. One-hundred ASA I-II patients undergoing reconstructive ankle surgery received infragluteal-parabiceps SNB using 0.4 mL/kg (maximum 35 mL) of levobupivacaine 0.625%. The end-point for injection was the first elicited EMR: inversion (I), plantar flexion (PF), dorsiflexion (DF), or eversion (E) at 0.2-0.4 mA. The frequencies of the EMRs were: I 40%, PF 43%, E 14%, and DF 3%. SNB was considered complete if both tibial and common peroneal nerves were blocked and failed if either analgesia to pinprick was not observed at 30 min or anesthesia at 60 min. Patients with an EMR of I demonstrated shorter mean times (+/-95% confidence interval [CI]) to complete the block with 8.5 (95% CI, 6.2-10.8) min compared to 27.0 (95% CI, 20.6-33.4) min after PF (P < 0.001) and 30.4 (95% CI, 24.9-35.8) min after E (P < 0.001). No rescue blocks were required in group I compared with 24% (P = 0.001) and 71% (P < 0.001) of patients in groups PF and E, respectively. We conclude that EMR type during nerve stimulator-assisted single-injection SNB predicts latency and success of complete SNB because the observed EMR is related to the positioning of the needle tip relative to the tibial and common peroneal nerves.