Continuous Perineural Infusion Research Articles

Effects of prolonged peri-neural bupivacaine infusion in rat sciatic nerves (axon and myelin).

Peripheral-nerve blocks (PNBs) using continuous-infusion of local anesthetics are used to provide perioperative analgesia. Yet little research exists to characterize the histopathological effects of continuous long-duration PNBs. Herein we test the hypothesis that continuous peri-neural bupivacaine infusion (3-day vs. 7-day infusion) contributes to histologic injury in a duration-dependent manner using an in vivo model of rat sciatic nerves. We placed indwelling catheters in 22 rats for infusion with low-dose (0.5mg/kg/hr) bupivacaine or normal saline proximal to the right sciatic nerves for 3 or 7 consecutive days. Hind-limb analgesia was measured using Von-Frey nociceptive testing. At infusion end, rats were sacrificed, bilateral nerves were sectioned and stained with hematoxylin and eosin and CD68 for evaluation of inflammatory response, and eriochrome to assess damage to myelin. Animals receiving continuous infusion of bupivacaine maintained analgesia as demonstrated by significant decrease (50% on average) in nociceptive response in bupivacaine-infused limbs across time points. Both 7-day saline and bupivacaine-infused sciatic nerves showed significantly-increased inflammation by H&E staining compared to untreated native nerve controls (P = 0.0001, P < 0.0001). Extent of inflammation did not vary significantly based on infusate (7-day saline vs. 7-day bupivacaine P > 0.99) or duration (3-day bupivacaine vs 7-day bupivacaine P > 0.99). No significant change in sciatic nerve myelin was found in bupivacaine-infused animals compared to saline-infused controls, regardless of duration. Long-duration (7-day) bupivacaine infusion provided durable post-operative analgesia, yet contributed to equivalent neural inflammation as short duration (3-day) infusion of bupivacaine or saline with no evidence of demyelination.

Erector Spinae Plane Block versus Continuous Perineural Local Anesthetic Infusion for Postoperative Pain Control After Supraclavicular Decompression for Neurogenic Thoracic Outlet Syndrome: A Matched Case-Control Comparison

The purpose of this study was to determine if single injection erector spinae plane blocks are associated with improved pain control, opioid use, numbness, length of stay, or patient satisfaction compared to intraoperatively placed continuous perineural infusion of local anesthetic after decompression of neurogenic thoracic outlet syndrome. This is a retrospective cohort study at a tertiary academic center of eighty patients that underwent supraclavicular decompression for thoracic outlet syndrome between May 2019 and January 2020. Forty consecutive patients treated with single-injection preoperative erector spinae plane blocks were retrospectively compared to 40 age- and gender-matched controls treated with continuous perineural infusion. The primary outcome of mean pain scores was not significantly different between the erector spinae and perineural infusion groups over the three-day study period (4.2-5.3 vs 3.0-5.1 P=0.08). On post-operative day 0, mean pain scores were significantly higher in the erector spinae group (4.2 vs 3.0, P=0.02). While statistically significant, the score was still lower in the erector spinae group on day 0 than on day 1,2, or 3 in either group. Opioid use, nausea, length of stay and patient satisfaction were also similar. Upper extremity numbness was significantly less severe in the erector spinae group (36% vs 73% moderate-extreme, P=0.03) at 6-month follow-up. Seventy-two-hour perineural local anesthetic infusion did not provide superior analgesia compared to preoperative single-injection erector spinae blocks. Furthermore, there was significantly less long-term postoperative numbness associated with erector spinae blocks compared to perineural local anesthetic infusion.

Bupivacaine-induced myotoxicity during a continuous perineural femoral block: case report

Introduction: Regional anesthesia is widely used for postoperative analgesia in total knee arthroplasty (TKA). Although it is a safe and effective procedure, serious complications may still develop. In the event of an unusual or torpid evolution, the possibility of local anesthetic-induced myotoxicity should be suspected.&#x0D; Case presentation: A 54-year old patient, American Society of Anesthesiologists (ASA) II, underwent TKA due to primary gonarthrosis. The analgesic technique used was a femoral nerve block associated with continuous perineural infusion. 24hours later, the patient’s medical condition deteriorated presenting pain, edema, and functional limitation of the thigh of the operated extremity. The symptoms were suggestive of myotoxicity, confirmed with diagnostic images leading to the removal of the catheter. The patient experienced then a significant improvement and was discharged 5 days after surgery.&#x0D; Conclusion: The diagnosis of myotoxicity from local anesthetics is rare, since its manifestations may be masked by the usual symptoms of the postoperative period. Early identification of the condition is fundamental to reduce its negative impact on the patient’s recovery and satisfaction. Since the scope of the damage depends particularly on the concentration and duration of the exposure to the local anesthetic agent, there is a need to implement protocols that enable an effective block with the lowest concentration and volume of the medication.

An Updated Review on Liposome Bupivacaine

In this review, we discuss the evidence for the use of liposome bupivacaine during the perioperative period when used for surgical site infiltration or as part of a peripheral/epidural nerve block. There is sparse high-quality evidence from randomized controlled trials that liposome bupivacaine is superior to traditional bupivacaine when surgically infiltrated. The evidence for liposome bupivacaine used as part of peripheral and epidural nerve blocks is promising, but its superiority is yet to be determined when compared to single-injection or continuous perineural infusions using unencapsulated (standard) long-acting local anesthetics. High-quality, adequately powered, prospective, randomized, controlled trials are still needed to adequately compare liposome bupivacaine to unencapsulated local anesthetic for peripheral nerve blocks and surgical site infiltration.

Efficacy and safety of epidural, continuous perineural infusion and adjuvant analgesics for acute postoperative pain after major limb amputation - a systematic review.

Treatment of pain following major limb amputations is often a clinical challenge in a patient population consisting mainly of elderly with underlying diseases. Literature on management of acute post-amputation pain is scarce. We performed a systematic review on this topic to evaluate the efficacy and safety of analgesic interventions for acute pain following major limb amputation. A literature search was performed in PubMed, Cochrane Central Register of Controlled Trials and Cochrane Database of Systematic Reviews using the following key words: [(amputation) AND (pain OR analgesi* OR pain relief)] AND (acute OR postoperative). Randomized controlled studies (RCTs) and observational studies investigating treatment of acute pain following major amputations for any indication (peripheral vascular disease, malignant disease, trauma) were included. The review was performed according to the standards described in the PRISMA statement. The Cochrane quality assessment tool was used to evaluate the risk of bias in the RCTs. Nineteen studies with total of 949 patients were included. The studies were generally small and heterogeneous on outcomes, study designs and quality. There were 16 studies on epidural or continuous perineural analgesia (CPI). Based on five RCTs (n=268) and two observational studies (n=49), epidural analgesia decreased the intensity of acute stump pain as compared to systemic analgesics, during the first 24 h after the operation. Based on one study epidural analgesia caused more adverse effects like sedation, nausea and motor block than continuous perineural local anesthetic infusion. Based on one RCT (n=21) and eight observational studies (n=501) CPI seemed to decrease opioid consumption as compared to systemic analgesics only, on the first three postoperative days, and was well tolerated. Only three trials investigated systemic analgesics (oral memantine, oral gabapentine, iv ketamine). Ketamine did not decrease acute pain or opioid consumption after amputation as compared to other systemic analgesics. Gabapentin did not decrease acute pain when combined to epidural analgesia as compared to epidural analgesia and opioid treatment, and caused adverse effects. The main finding of this systematic review is that evidence regarding pain management after major limb amputation is very limited. Epidural analgesia may be effective, but firm evidence is lacking. Epidural causes more adverse effects than CPI. The results on efficacy of CPI are indecisive. The data on adjuvant medications combined to epidural analgesia or CPI is limited. Studies on efficacy and adverse effects of systemic analgesics for amputation pain, especially concentrating on elderly patients, are needed.

Novel Regional Techniques for Total Knee Arthroplasty Promote Reduced Hospital Length of Stay: An Analysis of 106 Patients.

Novel regional techniques, including the adductor canal block (ACB) and the local anesthetic infiltration between the popliteal artery and capsule of the knee (IPACK) block, provide an alternative approach for controlling pain following total knee arthroplasty (TKA). This study compared 3 regional techniques (femoral nerve catheter [FNC] block alone, FNC block with IPACK, and ACB with IPACK) on pain scores, opioid consumption, performance during physical therapy, and hospital length of stay in patients undergoing TKA. All patients had a continuous perineural infusion, either FNC block or ACB. Patients in the IPACK block groups also received a single injection 30-mL IPACK block of 0.25% ropivacaine. Pain scores and opioid consumption were recorded at postanesthesia care unit discharge and again at 8-hour intervals for 48 hours. Physical therapy performance was measured on postoperative days (POD) 1 and 2, and hospital length of stay was recorded. We found no significant differences in the 3 groups with regard to baseline patient demographics. Although we observed no differences in pain scores between the 3 groups, opioid consumption was significantly reduced in the FNC with IPACK group. Physical therapy performance was significantly better on POD 1 in the ACB with IPACK group compared to the other 2 groups. Hospital length of stay was significantly shorter in the ACB with IPACK group. This study demonstrated that an IPACK block reduced opioid consumption by providing effective supplemental analgesia following TKA compared to the FNC-only technique. ACB with IPACK provided equivalent analgesia and improved physical therapy performance, allowing earlier hospital discharge.

Functional outcome and cost-effectiveness of outpatient vs inpatient care for complex hind-foot and ankle surgery. A retrospective cohort study

Study objectiveTo compare the postoperative functional outcome and the total cost associated with outpatient vs inpatient care following complex hind-foot and ankle surgery. DesignRetrospective, cohort study. SettingTertiary care center. PatientsForty patients, American Society of Anesthesiologists 1-3, of either sex undergoing elective complex hind-foot and ankle surgery (fusion, osteotomy, or multiple ligament repair). InterventionsBoth inpatients and outpatients received a continuous perineural infusion of local anesthetic for 48 hours at the core of a multimodal analgesic regimen. Patients were retrospectively identified, and an outpatient cohort was matched to an inpatient cohort in a 1:1 ratio for age, sex, baseline functional score, and type of surgery. MeasurementsThe primary outcome was functional outcome upon discharge of the surgical program as measured by the Lower Extremity Functional Score. Secondary outcomes were the incidence of surgical or anesthetic complications and the total perioperative cost of care. ResultsPatients in both cohorts had similar functional outcome on discharge of the surgical program. Analgesia was effective in both groups, and no complications were reported. The cost of care for outpatients was 54% lower than that for inpatients. ConclusionThis retrospective study suggests that outpatient care including an ambulatory perineural infusion of local anesthetic may be a cost-effective alternative to inpatient care after complex foot and ankle surgery.

Upper extremity nerve block: how can benefit, duration, and safety be improved? An update.

Upper extremity blocks are useful as both sole anaesthesia and/or a supplement to general anaesthesia and they further provide effective postoperative analgesia, reducing the need for opioid analgesics. There is without doubt a renewed interest among anaesthesiologists in the interscalene, supraclavicular, infraclavicular, and axillary plexus blocks with the increasing use of ultrasound guidance. The ultrasound-guided technique visualising the needle tip and solution injected reduces the risk of side effects, accidental intravascular injection, and possibly also trauma to surrounding tissues. The ultrasound technique has also reduced the volume needed in order to gain effective block. Still, single-shot plexus block, although it produces effective anaesthesia, has a limited duration of postoperative analgesia and a number of adjuncts have been tested in order to prolong analgesia duration. The addition of steroids, midazolam, clonidine, dexmedetomidine, and buprenorphine has been studied, all being off-label when administered by perineural injection, and the potential neurotoxicity needs further study. The use of perineural catheters is an effective option to improve and prolong the postoperative analgesic effect. Upper extremity plexus blocks have an obvious place as a sole anaesthetic technique or as a powerful complement to general anaesthesia, reducing the need for analgesics and hypnotics intraoperatively, and provide effective early postoperative pain relief. Continuous perineural infusion is an effective option to prolong the effects and improve postoperative quality.

Research Priorities Regarding Multimodal Peripheral Nerve Blocks for Postoperative Analgesia and Anesthesia Based on Hospital Quality Data Extracted from Over 1,300 Cases (2011–2014): Table 1

The use of additives with local anesthetics for peripheral nerve blocks has received considerable attention [1] due to the patient-centered goals of prolonging analgesic duration and possibly reducing local anesthetic-related toxicity. Applying such additives to single-injection nerve blocks also has the potential to reduce overhead [2] and disposables [3] costs, when compared with the costs related to continuous perineural infusions. Furthermore, recent research has elucidated in vivo animal sciatic nerve safety of the preservative-free combination of clonidine, buprenorphine, and dexamethasone (CBD) with the local anesthetic bupivacaine (BPV) [4]. Ropivacaine–CBD was previously demonstrated to be no more neurotoxic than plain ropivacaine to cultured primary sensory neurons harvested from rat dorsal root ganglia in vitro [5]. In our institution (Veterans Affairs Pittsburgh Healthcare System [VAPHS]), the lead author was in charged with creating a regional anesthesia (RA) and analgesia program for patients eligible for peripheral nerve blocks. For this new program, hospital administration was unable to budget resources for a perineural catheter-based acute pain service. Instead, the Medical Executive Board approved the lead author's recommendation to routinely use BPV–CBD off-label. These single-injection nerve block procedures are typically placed before surgery to provide postoperative analgesia and intraoperative anesthesia when feasible, and thus avoiding general endotracheal anesthesia (GETA). The Medical Executive Board tasked the lead author with per-patient quality assurance/quality improvement (QA/QI) data collection to evaluate comparative effectiveness (against historical controls) and outcomes (block duration and rebound pain [6,7], perineural complications, etc.). In accordance with Veterans Health Administration Handbook 1058.05, this manuscript was processed for authentication of nonresearch status of the activities prior to submission to this journal. Our institutional review board declared these clinical operations as “not research” at the time of program initiation (mid-2011) and annually since then during required reviews. The objective is to describe the patient outcomes …

Continuous Regional Anaesthesia Provides Effective Pain Management and Reduces Opioid Requirement Following Major Lower Limb Amputation

Postoperative stump pain after major lower limb amputation is a significant impediment to the recovery of amputees. The vast majority of patients require opioid analgesics following surgery, which are associated with opioid-related side-effects. Here, we investigate whether intraoperative placement of a peripheral nerve stump catheter followed by continuous infusion of local anesthetic is as effective at pain control as current analgesic practices. If beneficial, this procedure could potentially reduce post-amputation opioid consumption and opioid-related adverse effects. A retrospective chart review was conducted of 198 patients over a 4-year period who had undergone a major lower limb amputation for indications related to peripheral vascular disease. Postoperatively, 102 patients received a perineural catheter were compared to 96 patients who did not. The primary outcomes of this study were the amount of morphine equivalents used in the first 72 hours postoperatively and postoperative pain intensity in the first 24 hours. A total of 198 lower-limb amputations were selected for analyses. Multiple regression analyses indicated that perineural catheter use was associated with a lower cumulative postoperative opioid consumption over the first 72 hours but not postoperative pain scores at 24 hours. Perineural catheter use led to a 40% reduction in opioid use during the first 72 hours postoperatively. Mixed model repeated measures analysis demonstrated that this opioid reduction was consistent over time. Other variables related to total opioid use included age, pre-surgical chronic pain, pre-surgical opioid use, patient-controlled analgesia. Continuous perineural infusions of local anesthetic are a safe and effective method for reducing post-amputation opioid analgesic medications after major lower limp amputation.

Knee strength retention and analgesia with continuous perineural fentanyl infusion after total knee replacement: randomized controlled trial

Despite providing adequate pain relief, a femoral nerve block can induce postoperative muscle weakness after total knee arthoplasty (TKA). Fentanyl has been shown to have peripheral effects but has not been used as a perineural infusate alone after TKA. Sixty patients scheduled for TKA were randomized to one of three blinded groups: a continuous 24 h infusion of either fentanyl 3 μg/ml, ropivacaine 0.1%, or 0.9% normal saline through a femoral nerve sheath catheter at 10 ml/h. The main outcome was maximum voluntary isometric contraction (MVIC) in the quadriceps femoris (knee extension), measured by a handheld dynamometer (Nm/kg). Other variables assessed were preoperative and postoperative visual analog scale (VAS) scores, hamstrings MVIC (knee flexion), active range of motion of the operative knee, distance ambulated, incidence of knee buckling, supplemental morphine usage, postoperative side effects, and serum fentanyl levels. Quadriceps MVIC values were significantly greater in the fentanyl group compared to the group that received ropivacaine (median values, 0.08 vs. 0.03 Nm/kg; p = 0.028). The incidence of postoperative knee buckling upon ambulation was higher in the ropivacaine group compared to the fentanyl group, although not statistically significant (40% vs. 15 %, respectively; p = 0.077). VAS scores while ambulating were not significantly different between the fentanyl group and the ropivacaine group (p = 0.270). Postoperative morphine consumption, nausea and vomiting, and resting VAS scores were similar among the three groups. A continuous perineural infusion of fentanyl produced greater strength retention than ropivacaine post-TKA.

Super Glue—Stuck on You

To the Editor Gurnaney et al.1 describe great success using Dermabond (2-octyl cyanoacrylate glue) to decrease pericatheter leakage associated with continuous local anesthetic infusion. We note that the patients were discharged from the hospital with the catheter in situ and did not encounter any problems relating to removal of the catheter.1 We report our difficulties in 3 patients. We are a tertiary pediatric center and routinely use continuous perineural infusions for perioperative analgesia. We too have had problems with premature displacement or removal of the catheter in our population, especially in the upper limb. In response, we tried various combinations of suturing/subcutaneous tunneling/tissue glue in an attempt to prolong catheter survival. Combining tunneling with tissue glue seemed to be the most mechanically stable. We used n-butyl-2-cyanoacrylate monomer (Indermil Tissue Adhesive; Henkel Ltd., Dublin, Ireland) to secure the catheter to the skin. We have encountered difficulty in the removal of the catheter in 3 children in whom Indermil was used in combination with tunneling. A reasonable (moderate) amount of force was required to remove the catheters resulting in considerable distress to the patients in 2 cases, while the third required general anesthesia for catheter removal. We did not encounter a similar problem when catheters were tunneled and sutured before our introduction of Indermil glue. Suggestions have been made in the literature regarding the use of warm soapy water,2,3 acetone,2,3 or petroleum jelly3 to facilitate catheter removal after use of tissue adhesives. We are reluctant to use acetone on broken skin and would like to know if Gurnaney et al. used these or any other techniques to aid in removing the catheter. Deepa Bansi Jumani, DA, FRCA Peter Murphy, FRCA, MRCPCH Jackson Rees Department of Anaesthesia Alder Hey Children's Hospital NHS Foundation Trust Liverpool, United Kingdom [email protected]

Dermabond Decreases Pericatheter Local Anesthetic Leakage After Continuous Perineural Infusions

Dermabond Decreases Pericatheter Local Anesthetic Leakage After Continuous Perineural Infusions

Continuous Bilateral Posterior Lumbar Plexus Block with a Disposable Infusion Pump. Case Report

The number of bilateral total hip arthroplasties (THA) has been increasing every year. Postoperative analgesia by continuous perineural infusion of local anesthetic has been shown favorable results when compared to systemic analgesia. The use of elastomeric pumps has increased patient satisfaction when compared to electronic models. The objective of this report was to describe a case of continuous bilateral posterior lumbar plexus block with an elastomeric infusion pump in a patient submitted to bilateral hip arthroplasty. This is a 46 year-old female patient weighing 65 kg, 162 cm, with rheumatoid arthritis and hypertension, physical status ASA II, scheduled for bilateral THA in a single stage. She had been on corticosteroids for 13 years. Hemoglobin=10.1 g.dL⁻¹, hematocrit=32.7%. Routine monitoring. Spinal anesthesia with 15 mg of 0.5% isobaric bupivacaine. General anesthesia with propofol (PFS) and remifentanil, and intubation without neuromuscular blockers. Right THA and, at the end, lumbar plexus block with a stimulator and a set of 150 mm needle and injection of 20 mL of 0.2% bupivacaine and introduction of a catheter. Left THA and, at the end, the same procedure. Anesthetic dispersion and contrast were investigated. Elastomeric pump was installed with 0.1% bupivacaine (400 mL) at a rate of 14 mL.h⁻¹. The patient was transferred to the Intensive Care Unit (ICU). After 24 hour, a new pump was installed with the same solution. She did not receive any boluses for 50 hours. After removal of the catheter, pain was controlled with oral ketoprofen and dypirone. Continuous peripheral blockade with infusion of 0.1% bupivacaine with elastomeric pumps is a safe and effective procedure in adults.

Analgesic Effectiveness of a Continuous Versus Single-Injection Interscalene Block for Minor Arthroscopic Shoulder Surgery

The utility of continuous perineural infusions for lesser painful shoulder procedures is not well established. We hypothesized that the addition of a continuous interscalene ropivacaine infusion to a single-injection interscalene block would improve analgesia after minor arthroscopic shoulder surgery. An ultrasound-guided interscalene catheter targeting the C5-C6 roots/superior trunk was placed preoperatively in patients undergoing arthroscopic subacromial decompression, excision lateral clavicle, or stabilization. Ropivacaine 0.5% 30 mL was administered via this catheter before surgery was conducted under general anesthesia. All patients received dexamethasone and ondansetron antiemetic prophylaxis. At surgery conclusion, patients were randomly assigned to catheter removal in the postanesthesia care unit ("SS," n = 30) or to an elastomeric infusion of ropivacaine 0.2% 2 mL/hr with patient-controlled 5-mL boluses every hour ("Continuous," n = 31). Multimodal analgesia (acetaminophen, diclofenac, and rescue tramadol) was administered in both groups. Patients were questioned on postoperative days 1 and 2 for numerical rating pain score (0-10), supplemental tramadol consumption, and adverse effects of treatment. Median (quartiles) worst numerical rating pain score was lower in the Continuous group on day 1 on movement (SS = 4 [3-6], Continuous = 2 [0-4], P = 0.008) and at rest (SS = 2 [2-5], Continuous = 1 [0-3], P = 0.007) but was similar between groups on day 2. Median (quartiles) tramadol tablet consumption was lower in the Continuous group on both day 1 (SS = 1 [0-2], Continuous = 0 [0-0], P < 0.001) and day 2 (SS = 1 [0-2], Continuous = 0 [0-1], P = 0.017). Adverse effects of treatment were similar between groups except for numerically rated arm numbness, which was higher for the Continuous group. One patient in the SS group required 2 nights of hospitalization for intravenous opioid. After minor arthroscopic shoulder surgery, the addition of a continuous interscalene ropivacaine infusion to a single-shot interscalene block reduces pain, especially with movement, during the first 24 hrs.

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Elastomeric Pump Reliability in Postoperative Regional Anesthesia: A Survey of 430 Consecutive Devices

Postoperative analgesia via continuous perineural infusion of local anesthetics compares favorably with systemic analgesia. Elastomeric pumps increase patient satisfaction compared with electronic models. In in vitro investigations, infusions remained within 15% of their designated set rates. We assessed in vivo the infusion rate of elastomeric pumps in regional analgesia after orthopedic surgery. All consecutive elastomeric pumps were retrospectively studied during a 10-mo period. Perineural catheters were inserted preoperatively and connected postoperatively to elastomeric pumps filled with ropivacaine 0.2%. Before infusion, elastomeric pumps and ropivacaine were stored at room temperature. Two models of pumps were randomly used: Infusor LV5 (Baxter, France) or Easypump (Braun, Germany), both set at 5 mL/h. Nurses weighed the devices at the bedside using a portable electronic scale several times a day until catheter removal. Weights over time allowed accurate deflation profile assessment and flow rate calculation. An unchanged weight over time indicated either an obstructed catheter or an ineffective device. After connection to the catheter, 88 devices did not deflate (80 Easypump of 300 and 8 Infusor of 130, P < 0.0001). One Easypump was impossible to deflate, even after disconnection from its catheter. In two cases, catheters were obstructed. In 21 cases, catheters were removed 11 to 72 h later without being tested for patency. In 24 cases, pumps correctly deflated after catheters were injected without difficulty with a local anesthetic bolus. The remaining 40 devices spontaneously started to deflate 6 to 43 h after their connection. These 88 elastomeric pumps were associated with higher maximal visual analog scale scores during the first postoperative night than devices showing immediate deflation after connection (34 +/- 21 mm vs 26 +/- 19 mm, P = 0.006). Flow rates were calculated over a mean period of 54 +/- 18 h (Easypump) and 49 +/- 19 h (Infusor). The flow rates differed from those set by manufacturers (5 mL/h +/- 15%) in 47% of Easypump and in 34% of Infusor devices (P = 0.01). In vivo reliability of elastomeric pumps is different than in vitro. In the event of early insufficient postoperative perineural analgesia, an absence of deflation of the elastomeric pump must be considered. We recommend weighing these devices every 3 h during the first 24 h of infusion.

Postoperative pain management for shoulder arthroscopy in ambulatory surgery: comparation between single injection or continuous perineural infusion of local anesthetic

Postoperative pain management for shoulder arthroscopy in ambulatory surgery: comparation between single injection or continuous perineural infusion of local anesthetic

Continuous peripheral nerve blocks: state of the art

This review was performed through a Medline research to evaluate articles published between January 2004 and April 2005. Technical procedures, indications, drugs, infusion regimens, and complications of continuous peripheral nerve blocks were considered. A total of 27 articles were reviewed. With respect to technical procedures, the authors focused on advantages of stimulating catheters or ultrasound guidance. With the help of these techniques, a correct catheter placement as close to the targeted nerve as possible was obtained. The total amount of local anesthetic administered was thereby reduced. Using ultrasound needle guidance, the spread of local anesthetic around the nerve could be visualized. Articles dealing with the choice of local anesthetic showed equianalgesia and equipotency of continuous perineural infusion of levobupivacaine 0.125% and ropivacaine 0.2%. The best infusion regimen for postoperative analgesia appears to be a combination of a preset basal rate administered together with small bolus doses in almost all continuous peripheral nerve blocks. Overall, complications such as infections, local anesthetic toxic plasma levels, hematoma formation, or nerve injury seem to be rare in continuous peripheral nerve blockade. Continuous peripheral nerve blockade is an effective and safe technique for postoperative analgesia, even when administered at home. To optimize this technique, further studies are needed to help minimize the risk of side effects, improve techniques to locate the targeted nerve (stimulating catheters or ultrasound imaging) and choose less toxic drugs (levobupivacaine and ropivacaine) with more effective infusion regimens.

Continuous Perineural Infusions at Home

Continuous Perineural Infusions at Home