F. Kayser Enneking

Regional anesthesia in the patient receiving antithrombotic or thrombolytic therapy: American Society of Regional Anesthesia and Pain Medicine Evidence-Based Guidelines (Third Edition).

The actual incidence of neurologic dysfunction resulting from hemorrhagic complications associated with neuraxial blockade is unknown. Although the incidence cited in the literature is estimated to be less than 1 in 150,000 epidural and less than 1 in 220,000 spinal anesthetics, recent epidemiologic surveys suggest that the frequency is increasing and may be as high as 1 in 3000 in some patient populations. Overall, the risk of clinically significant bleeding increase with age, associated abnormalities of the spinal cord or vertebral column, the presence of an underlying coagulopathy, difficulty during needle placement, and an indwelling neuraxial catheter during sustained anticoagulation (particularly with standard heparin or low-molecular weight heparin). The need for prompt diagnosis and intervention to optimize is also consistently reported. In response to these patient safety issues, the American Society of Regional Anesthesia and Pain Medicine (ASRA) convened its Third Consensus Conference on Regional Anesthesia and Anticoagulation. Practice guidelines or recommendations summarize evidence-based reviews. However, the rarity of spinal hematoma defies a prospective randomized study, and there is no current laboratory model. As a result, the ASRA consensus statements represent the collective experience of recognized experts in the field of neuraxial anesthesia and anticoagulation. These are based on case reports, clinical series, pharmacology, hematology, and risk factors for surgical bleeding. An understanding of the complexity of this issue is essential to patient management.

Regional anesthesia in the anticoagulated patient: Defining the risks (the second ASRA Consensus Conference on Neuraxial Anesthesia and Anticoagulation)

Neuraxial anesthesia and analgesia provide several advantages over systemic opioids, including superior analgesia, reduced blood loss and need for transfusion, decreased incidence of graft occlusion, and improved joint mobility following major knee surgery. 1-4 New challenges in the management of patients undergoing neuraxial block have arisen over the last 2 decades, as medical standards for the prevention of perioperative venous thromboembolism were established. 5,6 Concern for patient safety in the presence of potent antithrombotic drugs has resulted in avoidance of regional anesthesia. Indeed, perioperative anesthesia and analgesia are often determined by the antithrombotic agent. 7 Conversely, although the anesthesia community is well aware of the potential for spinal bleeding, other specialties have only recently become cognizant of the risk, as documented by case reports

Continuous Popliteal Sciatic Nerve Block for Postoperative Pain Control at Home A Randomized, Double-Blinded, Placebo-Controlled Study

Background This randomized, double-blinded, placebo-controlled study investigated the efficacy of patient-controlled regional analgesia using a sciatic perineural catheter in the popliteal fossa and a portable infusion pump for outpatients having moderately painful, lower extremity orthopedic surgery. Methods Preoperatively, patients (n = 30) received a sciatic nerve block and perineural catheter in the popliteal fossa. Postoperatively, patients were discharged with both oral opioids and a portable infusion pump delivering study solution (0.2% ropivacaine or 0.9% saline) via the catheter for 3 days. Investigators and patients were blinded to random group assignment. Daily end-points included pain scores, opioid use and side effects, sleep quality, and symptoms of catheter- or local anesthetic-related complications. Results Ropivacaine (n = 15) infusion significantly reduced pain compared with saline (n = 15) infusion (P < 0.001). For example, the average pain at rest (scale: 0–10) on postoperative day 1 (median, 25th–75th percentile) was 4.0 (3.5–5.5) for the saline group, versus 0.0 (0.0–0.0) for the ropivacaine group (P < 0.001). Oral opioid use and related side effects were significantly decreased in the ropivacaine group. For example, on postoperative day 1, median tablet consumption was 8.0 (5.0–10.0) and 0.0 (0.0–0.0) for the saline and ropivacaine groups, respectively (P < 0.001). Sleep disturbance scores were more than 10-fold greater for saline administration than for ropivacaine infusion (P < 0.001). Overall satisfaction was significantly greater in the ropivacaine group. Other than two inadvertent catheter dislodgements, no catheter- or local anesthetic-related complications occurred. Conclusions After moderately painful orthopedic surgery of the lower extremity, ropivacaine infusion using a portable mechanical pump and a popliteal sciatic perineural catheter at home decreased pain, opioid use and related side effects, sleep disturbances, and improved overall satisfaction.

Continuous Peripheral Nerve Blocks at Home: A Review

Postoperative analgesia is generally limited to 12–16 h or less after single-injection regional nerve blocks. Postoperative analgesia may be provided with a local anesthetic infusion via a perineural catheter after initial regional block resolution. This technique may now be used in the outpatient setting with the relatively recent introduction of reliable, portable infusion pumps. In this review article, we summarize the available published data related to this new analgesic technique and highlight important issues related specifically to perineural infusion provided in patients’ own homes. Topics include infusion benefits and risks, indications and patient selection criteria, catheter, infusion pump, dosing regimen, and infusate selection, and issues related specifically to home-care.

Continuous infraclavicular brachial plexus block for postoperative pain control at home: a randomized, double-blinded, placebo-controlled study.

Background This randomized, double-blinded, placebo-controlled study investigated the efficacy of patient-controlled regional analgesia using an infraclavicular brachial plexus perineural catheter and a portable infusion pump for outpatients undergoing moderately painful, upper extremity orthopedic surgery. Methods Preoperatively, patients (n = 30) received an infraclavicular nerve block and perineural catheter. Postoperatively, patients were discharged home with oral narcotics and a portable infusion pump delivering study solution (0.2% ropivacaine or 0.9% saline) via the catheter for 3 days. Investigators and patients were blinded to random group assignment. Daily end points included pain scores at rest and with limb movement, narcotic use and side effects, sleep quality, patient satisfaction, and symptoms of catheter- or local anesthetic-related complications. Results Ropivacaine (n = 15) infusion significantly reduced pain compared with saline (n = 15) infusion (P < 0.001). For example, the average pain with movement (scale, 0–10) on postoperative day 1 was 6.1 ± 2.3 for the saline group versus 2.5 ± 1.6 for the ropivacaine group (P < 0.001). Oral narcotic use and related side effects were significantly decreased in the ropivacaine group. For example, on postoperative day 1, mean tablet consumption was 5.5 ± 2.4 and 1.7 ± 1.6 for the saline and ropivacaine groups, respectively (P < 0.001). Sleep disturbance scores were 10-fold greater for saline administration than for ropivacaine infusion (P < 0.001). Overall satisfaction was significantly greater in the ropivacaine group. No catheter- or local anesthetic-related complications occurred. Conclusion After moderately painful orthopedic surgery of the upper extremity, ropivacaine infusion using a portable, mechanical pump and an infraclavicular brachial plexus perineural catheter at home decreased pain, sleep disturbances, narcotic use and related side effects, and improved overall satisfaction.

Ambulatory continuous femoral nerve blocks decrease time to discharge readiness after tricompartment total knee arthroplasty: a randomized, triple-masked, placebo-controlled study.

Background:The authors tested the hypotheses that, compared with an overnight continuous femoral nerve block (cFNB), a 4-day ambulatory cFNB increases ambulation distance and decreases the time until three specific readiness-for-discharge criteria are met after tricompartment total knee arthroplasty. Methods:Preoperatively, all patients received a cFNB (n = 50) and perineural ropivacaine 0.2% from surgery until the following morning, at which time they were randomly assigned to either continue perineural ropivacaine or switch to perineural normal saline. Primary endpoints included (1) time to attain three discharge criteria (adequate analgesia, independence from intravenous analgesics, and ambulation of at least 30 m) and (2) ambulatory distance in 6 min the afternoon after surgery. Patients were discharged with their cFNB and a portable infusion pump, and catheters were removed on postoperative day 4. Results:Patients given 4 days of perineural ropivacaine attained all three discharge criteria in a median (25th–75th percentiles) of 25 (21–47) h, compared with 71 (46–89) h for those of the control group (estimated ratio, 0.47; 95% confidence interval, 0.32–0.67; P <0.001). Patients assigned to receive ropivacaine ambulated a median of 32 (17–47) m the afternoon after surgery, compared with 26 (13–35) m for those receiving normal saline (estimated ratio, 1.21; 95% confidence interval, 0.71–1.85; P = 0.42). Conclusions:Compared with an overnight cFNB, a 4-day ambulatory cFNB decreases the time to reach three important discharge criteria by an estimated 53% after tricompartment total knee arthroplasty. However, the extended infusion did not increase ambulation distance the afternoon after surgery. (ClinicalTrials.gov No. NCT00135889.)

Lower-extremity peripheral nerve blockade: Essentials of our current understanding

m b he American Society of Regional Anesthesia and Pain Medicine introduced an intensive orkshop focused on lower-extremity peripheral erve blockade in 2002. This review is the compiation of that work. Details concerning the techiques described in this text are available at the web ite ASRA.com, including video demonstrations of he blocks. Lower-extremity peripheral nerve locks (PNBs) have never been as widely taught or sed as other forms of regional anesthesia. Unlike he upper extremity, the entire lower extremity annot be anesthetized with a single injection, and njections are generally deeper than those required or upper extremity block. In addition, neuraxial echniques are widely taught and use alternative ethods for providing reliable lower-extremity ansthesia. Over the past decade, several developents have led to an increased interest in lower xtremity PNBs, including transient neurologic ymptoms associated with spinal anesthesia, inreased risk of epidural hematoma with the introuction of antithromboembolic prophylaxis regiens, and evidence of improved rehabilitation utcome with continuous lower-extremity PNBs. his review will focus on the anatomy of the lumosacral plexus and its terminal nerves, followed by

Ambulatory continuous interscalene nerve blocks decrease the time to discharge readiness after total shoulder arthroplasty: a randomized, triple-masked, placebo-controlled study.

Background:A continuous interscalene nerve block (CISB) may be used to provide analgesia after shoulder arthroplasty. Therefore, inpatient stays may be shortened if CISB (1) provides adequate analgesia without intravenous opioids and (2) improves shoulder mobilization. This study investigated the relationship between ambulatory CISB and the time to reach three discharge criteria after shoulder arthroplasty. Methods:Preoperatively, patients received a CISB. All patients received a perineural 0.2% ropivacaine infusion from surgery until 06:00 the following morning, at which time they were randomly assigned either to continue perineural ropivacaine or to switch to normal saline. The primary endpoint was the time from the end of surgery until three discharge criteria were attained (adequate analgesia, independence from intravenous analgesics, and tolerance to 50% of shoulder motion targets). Patients were discharged home as early as the afternoon after surgery with their CISB using a portable infusion pump. Results:Patients receiving perineural ropivacaine (n = 16) attained all three discharge criteria in a median (10th–90th percentiles) of 21 (16–41) h, compared with 51 (37–90) h for those receiving perineural normal saline (n = 13, P < 0.001). Unlike patients receiving perineural ropivacaine, patients receiving perineural normal saline often required intravenous morphine, but still experienced a higher degree of pain and tolerated less external rotation. Conclusions:An ambulatory CISB considerably decreases the time until readiness for discharge after shoulder arthroplasty, primarily by providing potent analgesia that permits greater passive shoulder movement and the avoidance of intravenous opioids. Additional research is required to define the appropriate subset of patients and assess the incidence of complications associated with earlier discharge.

Infraclavicular perineural local anesthetic infusion: a comparison of three dosing regimens for postoperative analgesia.

BackgroundIn this randomized, double-blind study, the authors investigated the efficacy of continuous and patient-controlled ropivacaine infusions via an infraclavicular perineural catheter in ambulatory patients undergoing moderately painful orthopedic surgery at or distal to the elbow. MethodsPreoperatively, patients (n = 30) received an infraclavicular perineural catheter and nerve block. Postoperatively, patients were discharged home with both oral analgesics and a portable infusion pump delivering 0.2% ropivacaine (500-ml reservoir) in one of three dosing regimens: the basal group (12 ml/h basal, 0.05-ml patient-controlled bolus dose), the basal–bolus group (8 ml/h basal, 4 ml bolus), or the bolus group (0.3 ml/h basal, 9.9 ml bolus). Investigators and patients were blinded to random group assignment. ResultsThe basal group (n = 10) required more oral analgesics than the basal–bolus group (P = 0.002) and had a shorter median infusion duration than the other two groups (P < 0.001 for both). The bolus group had the longest median infusion duration (P < 0.001 for both) but experienced an increase in breakthrough pain incidence (P = 0.004) and intensity (P = 0.04 vs. basal–bolus group) as well as sleep disturbances (P < 0.001 for both) compared with the other groups. Overall satisfaction was greatest in the basal–bolus group (9.7 ± 0.5 vs. 7.9 ± 1.7 and 8.1 ± 1.5; P < 0.05 for both). ConclusionsAfter moderately painful orthopedic surgery at or distal to the elbow, 0.2% ropivacaine delivered as a continuous infusion combined with patient-controlled bolus doses via an infraclavicular perineural catheter optimizes analgesia while minimizing oral analgesic use compared with basal- or bolus-only dosing regimens.

Interscalene perineural ropivacaine infusion:a comparison of two dosing regimens for postoperative analgesia.

Background and Objectives: A continuous interscalene nerve block with a perineural infusion of ropivacaine 0.2% at 8 mL/h has been shown to provide potent analgesia following moderately painful shoulder surgery. However, this high basal rate limits infusion duration for ambulatory patients who must carry the local anesthetic reservoir. We undertook this investigation to determine if the basal rate of an interscalene perineural ropivacaine infusion could be decreased by 50% with a concurrent 200% increase in patient-controlled bolus dose without compromising infusion benefits in ambulatory patients undergoing moderately painful orthopedic shoulder surgery. Methods: Preoperatively, patients (n = 24) received an interscalene perineural catheter and nerve block. Intraoperatively, patients received a standardized general anesthetic. Postoperatively, patients were discharged home with a portable infusion pump delivering ropivacaine 0.2% (500 mL reservoir) with a basal rate of 8 mL/h and a 2 mL patient-controlled bolus available each hour (“8/2” group, n = 12) or a 4 mL/h basal rate and 6 mL bolus dose (“4/6” group, n = 12), delivered in a randomized, double-blinded manner. Results: Patients in the 4/6 group had higher baseline pain scores only on postoperative day (POD) 2 (P = .011). However, these patients also experienced an increase in breakthrough pain incidence (5.8 boluses/d v 3.2, P = .035) and intensity (“worst” pain = 8/10 v 4/10, P < .05), sleep disturbances (2.0 v 0.0, P < .001), and a decrease in analgesia satisfaction (8 v 10, P = .003). Patients in the 8/2 group exhausted their local anesthetic reservoirs after a median of 61 hours, while the 4/6 group had a median of 131 mL remaining at infusion discontinuation after a median of 75 hours (P < .001). Conclusions: Following moderately painful ambulatory shoulder surgery, decreasing an interscalene perineural ropivacaine 0.2% basal rate from 8 to 4 mL/h provides similar baseline analgesia and lengthens infusion duration, but compromises other infusion benefits.