Buprenorphine added to the local anesthetic for axillary brachial plexus block prolongs postoperative analgesia

BACKGROUND AND OBJECTIVES: Buprenorphine added to local anesthetic solutions for supraclavicular block was found to triple postoperative analgesia duration in a previous study when compared with local anesthetic block alone. That study, however, did not control for potentially confounding factors, such as the possibility that buprenorphine was affecting analgesia through intramuscular absorption or via a spinal mechanism. To specifically delineate the role of buprenorphine in peripherally mediated opioid analgesia, the present study controlled for these 2 factors. METHODS: Sixty American Society of Anesthesiologists (ASA) P.S. I and II, consenting adults for upper extremity surgery, were prospectively assigned randomly in double-blind fashion to 1 of 3 groups. Group I received local anesthetic (1% mepivacaine, 0.2% tetracaine, epinephrine 1:200,000), 40 mL, plus buprenorphine, 0.3 mg, for axillary block, and intramuscular (IM) saline. Group II received local anesthetic-only axillary block, and IM buprenorphine 0.3 mg. Group III received local anesthetic-only axillary block and IM saline. Postoperative pain onset and intensity were compared, as was analgesic medication use. RESULTS: The mean duration of postoperative analgesia was 22.3 hours in Group I; 12.5 hours in group II, and 6.6 hours in group III. Differences between groups I and II were statistically significant (P =.0012). Differences both between groups I and III and II and III were also statistically significant (P <.001). CONCLUSIONS: Buprenorphine-local anesthetic axillary perivascular brachial plexus block provided postoperative analgesia lasting 3 times longer than local anesthetic block alone and twice as long as buprenorphine given by IM injection plus local anesthetic-only block. This supports the concept of peripherally mediated opioid analgesia by buprenorphine.     

Clonidine combined with a long acting local anesthetic does not prolong postoperative analgesia after brachial plexus block but does induce hemodynamic changes

Clonidine in brachial plexus block prolongs analgesia of local anesthetics of short and intermediate duration. We performed a prospective randomized double-blinded study to determine the efficacy and adverse effects of clonidine mixed with a long-acting local anesthetic on postoperative analgesia. Sixty adult patients underwent elective rotator cuff repair using interscalene brachial plexus block combined with general anesthesia and were randomly divided into one of the following three groups. Placebo (n = 20): interscalene block with 40 mL of 0.5% bupivacaine with epinephrine (1/200000) and 1 mL of 0.9% saline, completed by 1 mL of 0.9% saline IM in the controlateral shoulder; Control (n = 20): interscalene block with 40 mL of 0.5% bupivacaine with epinephrine and 1 mL of 0. 9% saline, completed by 150 microg (=1 mL) of clonidine IM; Clonidine (n = 20): interscalene block with 40 mL of 0.5% bupivacaine with epinephrine and 150 microg (=1 mL) of clonidine, completed by 1 mL of 0.9% saline IM. During anesthesia hemodynamic variables and fractional expired isoflurane concentration (FeISO) were recorded. The following postoperative variables were assessed: duration of interscalene block, quality of pain relief on a visual analog scale, side effects, and consumption of morphine with a patient-controlled analgesia device over 48 h. Patient characteristics were comparable. During anesthesia mean arterial pressure, heart rate, and FeISO were significantly decreased in Clonidine and Control groups compared with Placebo group. Duration of analgesia, defined as the time elapsed from interscalene injection to the first morphine request, was 983 +/- 489 min in the Placebo, 909 +/- 160 min in the Control, and 829 +/- 159 min in the Clonidine groups. Pain scores and consumption of morphine at 24 h and 48 h showed no differences among the three groups. We conclude that adding 150 microg of clonidine in interscalene block does not prolong analgesia induced by 40 mL of bupivacaine 0.5% with epinephrine, but decreases mean arterial blood pressure and heart rate. Implications: Clonidine in brachial plexus block does not improve postoperative analgesia when mixed with a long-lasting anesthetic. Nevertheless, with or without clonidine, bupivacaine in interscalene block provides a long-lasting analgesia of approximately 15 h.     

Continuous versus single-injection lumbar plexus blocks: comparison of the effects on morphine use and early recovery after total knee arthroplasty

BACKGROUND AND OBJECTIVES: Continuous lumbar plexus infusion of local anesthetic after total knee arthroplasty has been shown to improve analgesia and early recovery as compared with patient-controlled analgesia (PCA) morphine. Any benefit of an infusion over a single-injection lumbar plexus block has not been directly shown however. METHODS: In a double-blind, randomized, controlled trial, 32 patients undergoing total knee arthroplasty were randomly allocated to 1 of 2 groups: 0.1% levobupivacaine infusion or saline infusion. Preoperatively, all patients received a lumbar plexus block with 25 mL 0.5% levobupivacaine using a posterior approach with a catheter left in situ, a sciatic nerve block with 15 mL 0.5% levobupivacaine, and a spinal anesthetic. At the end of surgery, 0.1% levobupivacaine or saline was infused into the catheter at 10 mL/h for 48 hours. All patients also received PCA morphine. The primary endpoint was morphine use from the PCA machine. Secondary endpoints included pain scores, day of first postoperative mobilization, and nausea. RESULTS: Patients receiving the levobupivacaine infusion used significantly less morphine than those receiving saline (19 mg [interquartile range (IQR) 8.5-29.5] vs 32 mg [IQR 23.5-53.0], P = .04) and also mobilized earlier postoperatively (day 1 or 2 [levobupivacaine] vs day 2 or 3 [saline], P = .001). Pain scores were similar. CONCLUSION: Postoperative infusion of local anesthetic around the lumbar plexus reduces morphine requirement and improves early recovery after total knee arthroplasty as compared with a single-injection block.     

Evaluation of peripheral morphine analgesia for lumpectomy and axillary node dissection: a randomized, double-blind, placebo-controlled study

BACKGROUND AND OBJECTIVES: Morphine may elicit potent antinociceptive effects by binding and activating peripheral opioid receptors. However, the results in clinical studies have varied. We examined the postoperative analgesic effects of incisional morphine in patients undergoing lumpectomies and axillary node dissections for breast cancer. For this purpose, a concentration of morphine within the range (0.25-0.6%) of those utilized in previous studies for postarthroscopy analgesia was chosen (0.6%). METHODS: Forty-five patients scheduled to undergo a lumpectomy and axillary node dissections for breast cancer were enrolled in this study after receiving Ethics Committee approval and patient consent. Patients were randomized to undergo irrigation of the surgical sites for 5 minutes prior to skin closure with 6 mg morphine diluted in 100 mL 0.9% normal saline (NS) and placebo intramuscular (i.m.) (peripheral MS group), 100 mL of 0.9% NS alone and placebo i.m. (placebo group), or 100 mL of 0.9% NS and 6 mg morphine i.m. in the deltoid muscle (i.m. MS group) in a double-blind fashion. In the postanesthesia care unit, patients received fentanyl via a patient-controlled analgesia (PCA) device programmed to deliver 25 microg every 10 minutes to a maximum dose of 150 microg/h. Patients were evaluated for pain using a visual analog scale card from 0-10, opioid consumption, and incidences of side effects at 2, 6, 12, 18, and 24 hours after surgery. RESULTS: All patients had adequate analgesia at rest and during arm movement with visual analog pain scores (VAPS) <3/10 throughout the study period. There were no significant differences in demographics, total fentanyl consumption (500 vs. 475 vs 933 microg, respectively; P = .2), VAPS at rest and during arm movement as well as fentanyl consumption at the different evaluation points among the three groups. CONCLUSIONS: These results suggest that under the conditions of the study protocol, there is no value in utilizing morphine in solution at the surgical site for postoperative lumpectomy and axillary node dissection analgesia.     

氟比洛芬酯复合小剂量芬太尼用于胃肠外科患者术后静脉自控镇痛的临床观察

目的:评估氟比洛芬酯复合小剂量芬太尼在胃肠手术后患者静脉自控镇痛(patient controlled intravenous analgesia,PCIA)中的效果和安全性.方法:90例择期行胃肠外科手术患者,均采用静脉吸入复合麻醉,术后行PCIA,并根据不同的用药方法随机分为A、B、C 3组,每组30例.A组:芬太尼1.0mg+生理盐水至100 mL;B组:氟比洛芬酯100 mg+芬太尼1.0 mg+生理盐水至100 mL;C组:氟比洛芬酯1 00 mg+芬太尼0.5 mg+生理盐水至1 00 mL. PCIA工作方式采用持续背景剂量(2 mL/h)配合单次按压剂量(0.5 mL/次),锁定时间为1 5 min.分别采用视觉模拟(visual analogue scales,VAS)评分评估24 h内的镇痛效果,记录24 h内PICA按压次数,恶心、呕吐等不良反应的发生情况.结果:患者均获得较好的镇痛效果.3组VAS评分及按压次数差异无统计学意义(P>0.05);随访观察A组和B组恶心、呕吐、嗜睡等不良反应发生率明显高于C组(P<0.05);镇痛期间A组2例发生呼吸抑制,3组均未发生异常出血等并发症.结论:相对于单独应用芬太尼,氟比洛芬酯复合小剂量芬太尼应用于胃肠外科术后静脉镇痛效果相同,但能够有效减少芬太尼的用量,降低不良反应的发生率.     

The clinical efficacy and pharmacokinetics of intraperitoneal ropivacaine for laparoscopic cholecystectomy.

Postoperative pain after laparoscopic surgery is less than after laparotomy, and patients may benefit from an intraperitoneal injection of local anesthetic. Thirty-seven ASA physical status I or II patients received in double-blinded fashion 20 mL of 0.9% saline solution (placebo), ropivacaine 0.25% (Rop 0.25%), or ropivacaine 0.75% (Rop 0.75%) immediately after trocar placement and at the end of surgery. We measured pain and morphine consumption until 20 h after surgery. Plasma ropivacaine concentrations were measured. The three groups were comparable for shoulder pain, parietal pain, and incidence of side effects. Visceral pain at rest, during cough, and on movement and total consumption of morphine were significantly smaller in Groups Rop 0.25% and Rop 0.75% when compared with Placebo. Although no adverse effect occurred in any patient, the largest dose led to large plasma concentrations of ropivacaine (2.93 +/- 2.46 microg/mL and 3.76 +/- 3.01 microg/mL after the first and second injection, respectively). We conclude that intraperitoneal administration of ropivacaine before and after surgery significantly decreases postoperative pain. Because the smaller dosage (2 x 50 mg) provided similar analgesia and was associated with significantly smaller plasma concentrations than the larger dosage (2 x 150 mg), this smaller dosage seems more appropriate. IMPLICATIONS: Intraperitoneal ropivacaine 100 mg injected during laparoscopic cholecystectomy significantly decreased postoperative pain when compared with injection of intraperitoneal placebo. At this dose, plasma concentrations remained in the nontoxic range,     

A double-blind comparison of intrathecal S(+) ketamine and fentanyl combined with bupivacaine 0.5% for Caesarean delivery

BACKGROUND: In this prospective, randomized, double-blind, controlled study, we investigated the sensory, motor and analgesic block characteristics of S(+) ketamine, fentanyl and saline given intrathecally (IT) in addition to 0.5% plain bupivacaine (10 mg) for spinal analgesia. METHODS: Ninety ASA I or II adult patients undergoing Caesarean section were randomly allocated to receive 1.0 mL of 0.9% saline in Group S (n = 30), 0.05 mg kg-1 of S(+) ketamine (1.0 mL) in Group K (n =30) or 25 microg (1.0 mL) of fentanyl in Group F (n =30) following 10 mg of plain bupivacaine 0.5% IT. We recorded onset and duration of sensory and motor block, time to reach the maximal dermatomal level of sensory block and duration of spinal analgesia. RESULTS: The onset time of sensory and motor block was significantly shorter in Groups K and F than in Group S (P < 0.014). Their duration was significantly longer in Group F than in Groups K and S (P < 0.009). The time to reach the maximal dermatomal level of sensory block was significantly shorter in Groups K and F than in Group S (P < 0.001). The duration of spinal analgesia was significantly longer in Group F than in Groups K and S (P < 0.001). CONCLUSION: In patients undergoing Caesarean section with spinal analgesia, the addition of S(+) ketamine (0.05 mg kg-1) IT to 10 mg of spinal plain bupivacaine (0.5%) led to rapid onset of both sensory and motor blockade and enhanced the segmental spread of spinal block without prolonging the duration of spinal analgesia, whereas fentanyl provided prolonged analgesia.     

Femoral block provides superior analgesia compared with intra-articular ropivacaine after anterior cruciate ligament reconstruction

BACKGROUND AND OBJECTIVES: Arthroscopic anterior cruciate ligament (ACL) reconstruction of the knee is a painful procedure requiring intensive postoperative pain management. This prospective study investigates analgesic quality after a femoral block as compared with intra-articular injection of local anesthetic. METHODS: Eighty patients scheduled for elective ACL repair under general anesthesia were included in our study. Upon completion of surgery, the patients were randomly assigned into 1 of 2 groups: femoral group (n = 40) received a femoral block with 20 mL 1% ropivacaine; intra-articular group (n = 40) received 20 mL 1% ropivacaine injected intra-articularly. During the first 24 hours after surgery, all patients received 2 g propacetamol and 100 mg ketoprofen, intravenously. Additional postoperative analgesia was available with parenteral morphine if required. Analgesic duration was defined as the time from end of surgery to the first requirement for a supplemental analgesic. Data collection included patient demographics, visual analog scale (VAS) scores, analgesic duration, and morphine use. Analysis of variance (ANOVA) test was used to compare the 2 groups. RESULTS: VAS score in the recovery room and during rehabilitation was higher in the intra-articular group than in the femoral group (P <.001). Morphine use was lower in the femoral group than in the intra-articular group (P <.001). Similarly, analgesic duration was longer in the femoral group than the intra-articular group (P <.0001). CONCLUSIONS: Compared with intra-articular injection of local anesthetic, femoral nerve block (FNB) provides better analgesia and allows a significant morphine-sparing effect after ACL repair.     

Intrathecal morphine for post-thoracotomy pain

We wished to investigate possible differences in the duration of postoperative analgesia and the incidence of respiratory depression after the intrathecal injection in the lumbar area of 10 micrograms/kg morphine in hypobaric and hyperbaric solution for relief of post-thoracotomy pain. Twenty-nine patients received morphine plus dextrose (hyperbaric) and 21 received morphine in preservative-free normal saline. The duration of analgesia was longer with the morphine in the normal saline group than in the hyperbaric group (P less than 0.04). One patient developed delayed respiratory depression. Our data support the use of morphine in normal saline mixtures for greater duration of analgesia after thoracic operations.     

Does intrathecal fentanyl produce acute cross-tolerance to i.v. morphine?

We have examined the hypothesis that intrathecal fentanyl at operation can increase postoperative i.v. morphine requirements. We studied 60 patients undergoing Caesarean section. All received intrathecal 0.5% plain bupivacaine 2 ml combined with either fentanyl 0.5 ml (25 micrograms) (group F) (n = 30) or normal saline 0.5 ml (group S) (n = 30). In addition, 10 ml of an extradural solution (fentanyl 1 ml (50 micrograms) combined with 0.5% bupivacaine 9 ml) was administered after delivery. Extradural solution was only given before delivery if the intrathecal injection failed to produce a block above T6 or the patient required further analgesia. Postoperative analgesia was provided with i.v. morphine patient-controlled analgesia. At operation, intrathecal fentanyl reduced the need to administer extradural solution before delivery, increased the anaesthetist's satisfaction with analgesia and reduced nausea, but increased pruritus. Up to 6 h after delivery there was no difference in postoperative morphine requirements or pain scores. Between 6 h and 23 h there was a 63% increase in morphine requirements in group F. We consider the most likely explanation for this finding to be that intrathecal fentanyl induced acute spinal opioid tolerance.      

Interscalene brachial plexus block with continuous intraarticular infusion of ropivacaine

Providing intraarticular analgesia with a continuous infusion of local anesthetic via a disposable infusion pump has gained popularity. Despite the prevalence of this technique, data comparing this method of analgesia to conventional regional anesthesia are not available. We present a prospective study that compared a single-dose interscalene block with a single-dose interscalene block plus continuous intraarticular infusion of local anesthetic. Forty patients scheduled for shoulder arthroscopy were entered in this prospective, double-blinded study. All patients received an interscalene brachial plexus block as their primary anesthetic. Patients were randomly assigned to 1 of 2 groups: 1. interscalene block with 1.5% mepivacaine (40 mL) followed by a postoperative intraarticular infusion of 0.5% ropivacaine at 2 mL/h, or 2. interscalene block with 0.5% ropivacaine (40 mL) followed by a postoperative intraarticular infusion of 0.9% saline (placebo) at 2 mL/h. Postoperative infusions were maintained for 48 h. Visual analog scale pain scores and postoperative oxycodone consumption were measured for 48 h. Visual analog scale scores at rest and with ambulation in the Mepivacaine/Intraarticular Ropivacaine group were reduced when compared with the Ropivacaine/Saline group (rest: P = 0.003, ambulation: P = 0.006). Oxycodone consumption was also decreased (28 +/- 21 mg vs 44 +/- 28 mg, P = 0.046), respectively. We conclude that a brachial plexus block with 1.5% mepivacaine and a continuous intraarticular infusion of 0.5% ropivacaine at 2 mL/h provides improved analgesia for minor surgery at 24 and 48 h versus a single-injection interscalene block with 0.5% ropivacaine.     

Evaluation of efficacy and plasma concentrations of ropivacaine in continuous axillary brachial plexus block: high dose for surgical anesthesia and low dose for postoperative analgesia

BACKGROUND AND OBJECTIVES: Ropivacaine is a potent local anesthetic that, experimentally at low concentrations, produces an effective block of pain conducting nerve fibers. Therefore, it was hypothesized that 0.1% and 0.2% ropivacaine would provide clinically adequate postoperative analgesia in continuous axillary plexus block. METHODS: Sixty patients (ASA I-II) scheduled for elective hand or forearm surgery received 5 mg/kg of 0.75% ropivacaine for axillary block using nerve stimulator technique. One hour later, in random order, a continuous infusion of either 0.1% ropivacaine (0.125 mg/kg/h), 0.2% ropivacaine (0.25 mg/kg/h) or saline 6 to 11 mL/h was started. RESULTS: The mean total ropivacaine dose for the surgical block was 5.1 to 5.2 mg/kg with the supplementation. All patients were pain free for the first 12 to 15 hours after the block. The need for postoperative analgesics during the infusion was similar in all groups. After the initial block, the maximum plasma concentrations (mean 2.5 microg/mL) were measured at 45 or 60 minutes after injection. The highest individual plasma concentration was 4.2 microg/mL. Despite the high venous peak concentration, no toxic reactions were observed. The mean peak plasma concentration (Cmax) was 2.2+/-0.5 microg/mL for saline, 2.6+/-0.8 microg/mL for 0.1% ropivacaine, and 2.6+/-0.7 microg/mL for 0.2% ropivacaine. During the continuous infusion of 24 hours, the ropivacaine concentration declined steadily. CONCLUSIONS: Ropivacaine is safe and effective for axillary brachial plexus block. The continuous infusion of 0.1% or 0.2% ropivacaine was no more beneficial than an infusion of saline in relieving postoperative pain in patients having elective hand surgery. None of the infusions were sufficient to adequately treat the patients' pain without the addition of adjunct agents.     

Combined intrathecal morphine and bupivacaine for cesarean section

The effects of adding 0.2 mg preservative-free morphine sulfate in 0.2 ml solution to hyperbaric spinal bupivacaine were evaluated in a double-blind randomized prospective study of 34 patients undergoing elective repeat cesarean section. In the control patients (n = 17), 0.2 ml saline instead of morphine was added to bupivacaine. The intrathecal morphine significantly improved intra- and postoperative analgesia, e.g., 82% of patients given morphine compared with 41% of the control patients did not require analgesic supplementation to the spinal anesthesia during surgery; postoperatively, the former patients did not request additional analgesia for 27 +/- 0.7 hours (mean +/- SEM) compared with 2 +/- 0.3 hours in the control patients. Neonatal condition was not adversely affected by this small dose of morphine administered 11 +/- 1 minutes before delivery. Combining 0.2 mg morphine with hyperbaric spinal bupivacaine for cesarean section is a safe and effective method of improving intraoperative pain relief and providing adequate prolonged postoperative analgesia.     

Prophylacticip injection of bupivacaine and/or morphine does not improve postoperative analgesia after laparoscopic gynecologic surgery

PURPOSE: To determine the effectiveness of ip bupivacaine and/or morphine for postoperative analgesia after laparoscopic surgery. A controversy exists on the effectiveness and clinical value of ip injection of local anesthetics for postoperative analgesia. A possible peripheral analgesic effect of morphine after ip injection remains debated as well. METHODS: We conducted a randomized, double-blinded, study to compare the efficacy of prophylactic ip administration of 0.9% saline (n = 16), 0.5% bupivacaine (100 mg, n = 15), morphine (3 mg, n = 16) and a mixture with 0.5% bupivacaine (100 mg) and morphine (3 mg, n = 18) to reduce both postoperative pain scores and analgesic requirements after gynecologic laparoscopic surgery. A multimodal analgesia regimen (acetaminophen, nonsteroidal anti-inflammatory drugs and morphine) was used for postoperative analgesia. RESULTS: No difference was observed in postoperative pain scores (visual analogue scale at rest and on coughing), or analgesic requirements during the first 24 postoperative hours between the four groups. There was also no significant intergroup difference in sedation scores and incidence of nausea and vomiting. CONCLUSION: When multimodal postoperative analgesia is used, prophylactic ip administration of 100 mg bupivacaine and/or 3 mg morphine does not significantly improve postoperative analgesia in patients undergoing laparoscopic gynecologic surgery.     

Addition of bupivacaine 1.25 mg to fentanyl confers no advantage over fentanyl alone for intrathecal analgesia in early labour

PURPOSE: a) To evaluate the effect of adding 1.25 mg of bupivacaine to intrathecal fentanyl on the duration of analgesia in an Asian population and b) to examine if the baricity of the local anesthetic at this dose has any bearing on the duration and quality of block. METHODS: Forty-eight parturients in early labour received combined spinal epidural (CSE) analgesia to evaluate a) the effect of adding 1.25 mg of bupivacaine to intrathecal (IT) fentanyl 25 microg on the duration of analgesia and b) the effect of baricity of intrathecal local anesthetic on the duration and quality of the block. Patients were randomly allocated to receive: IT fentanyl 25 microg plus normal saline (Group f, n=16), IT fentanyl 25 microg plus plain bupivacaine 1.25 mg (Group f+pb, n=16) and IT fentanyl 25 microg plus heavy bupivacaine 1.25 mg (Group f+hb, n=16). The two components of the IT injectate (total of 2.25 mL) were given sequentially. RESULTS: Group f+hb had the lowest sensory dermatomal block (T7 vs T4 (Group f), T5 (Group f+pb), P <0.01). There were no differences in the duration of analgesia and incidence of side effects among the groups. CONCLUSION: We found no advantage of adding 1.25 mg bupivacaine to fentanyl 25 microg. At this dose, the baricity of bupivacaine has no effect on the duration of analgesia.     

Postoperative analgesia with epidural morphine after hip operations (author's transl)

80 patients undergoing hip surgery under lumbar epidural block have been studied (double blind) for postoperative analgesia. There were 4 groups, of 20 patients each, who received a single epidural injection of 0 mg, 2 mg or 4 mg morphine in 1 ml of saline added to 6 ml bupivacaine 0.5% or 4 mg morphine in 6 ml saline. In the morphine groups analgesia lasted between 37 and 50 hours. No neurological side-effects or severe respiratory depression have was observed; but a significant rise of paCO2 was found. Other side-effects were nausea/vomiting and the need for catheterisation in about 50% of patients. We conclude, that the indications for epidural analgesia with morphine have to be chosen carefully.     

Nerve stimulator and multiple injection technique for upper and lower limb blockade: failure rate, patient acceptance, and neurologic complications. Study Group on Regional Anesthesia

To evaluate the failure rate, patient acceptance, effective volumes of local anesthetic solution, and incidence of neurologic complications after peripheral nerve block performed using the multiple injection technique with a nerve stimulator, we prospectively studied 3996 patients undergoing combined sciatic-femoral nerve block (n = 2175), axillary blocks (n = 1650), and interscalene blocks (n = 171). The success rate and mean injected volumes of local anesthetic were: 93% with 22.6 +/- 4.5 mL in the axillary, 94% with 24.5 +/- 5.4 mL in the interscalene, and 93% with 28.1 +/- 4.4 mL in the sciatic-femoral nerve blocks. Patients receiving combined sciatic-femoral nerve block showed more discomfort during block placement and worse acceptance of the anesthetic procedure than patients receiving brachial plexus anesthesia. During the first month after surgery, 69 patients (1.7%) developed neurologic dysfunction on the operated limb. Complete recovery required 4-12 wk in all patients but one, who required 25 wk. The only variable showing significant association with the development of postoperative neurologic dysfunction was the tourniquet inflation pressure (<400 mm Hg compared with >400 mm Hg, odds ratio 2.9, 95% confidence intervals 1.6-5.4; P < 0.001). We conclude that using the multiple injections technique with a nerve stimulator results in a success rate of >90% with a volume of <30 mL of local anesthetic solution and an incidence of transient neurologic complication of <2%. Implications: Based on a prospective evaluation of 3996 consecutive peripheral nerve blocks, the multiple injection technique with nerve stimulator allows for up to 94% successful nerve block with <30 mL of local anesthetic solution. Although the data collection regarding neurologic dysfunction was limited, the withdrawal and redirection of the stimulating needle was not associated with an increased incidence of neurologic complications. Sedation/analgesia should be advocated during block placement to improve patient acceptance.     

Buprenorphine added to the local anesthetic for brachial plexus block to provide postoperative analgesia in outpatients

BACKGROUND AND OBJECTIVES: Over the past 10 years, several studies have suggested that the addition of certain opiates to the local anesthetic used for brachial block may provide effective, long-lasting postoperative analgesia. One of these studies indicated that the agonist-antagonist, buprenorphine, added to bupivacaine provided a longer period of postoperative analgesia than the traditional opiates, but in this study, it is impossible to determine the relative contributions of the local anesthetic and the opiate to the postoperative analgesia because of the extremely long duration of the anesthesia provided by the local anesthetic, bupivacaine. By repeating the study using a local anesthetic of a shorter duration, the present study delineates more clearly the contribution of the buprenorphine to postoperative analgesia when added to a shorter-acting local anesthetic. METHODS: Forty, healthy, consenting adult patients scheduled for upper extremity surgery were enrolled in the study. Premedication was provided by intravenous midazolam 2 mg/70 kg and anesthesia by a subclavian perivascular brachial plexus block. The patients were assigned randomly to 1 of 2 equal groups based on the agents used for the blocks. The patients in group I received 40 mL of a local anesthetic alone, while those in group II received the same local anesthetic plus buprenorphine 0.3 mg. The study was kept double-blind by having 1 anesthesiologist prepare the solutions, a second anesthesiologist perform the blocks, and a third anesthesiologist monitor the anesthesia and analgesia thereafter, up to and including the time of the first request for an analgesic medication. The data were reported as means (+/- SEM), and differences between groups were determined using repeated measures of analysis of variance (ANOVA) and chi(2), followed by the Fisher exact test for post hoc comparison. A P value of less than.05 was considered to be statistically significant. RESULTS: The mean duration of postoperative pain relief following the injection of the local anesthetic alone was 5.3 (+/- 0.15) hours as compared with 17.4 (+/- 1.26) hours when buprenorphine was added, a difference that was statistically (and clinically) significant (P <.0001). CONCLUSIONS: The addition of buprenorphine to the local anesthetic used for brachial plexus block in the present study provided a 3-fold increase in the duration of postoperative analgesia, with complete analgesia persisting 30 hours beyond the duration provided by the local anesthetic alone in 75% of the patients. This practice can be of particular benefit to patients undergoing ambulatory upper extremity surgery by providing prolonged analgesia after discharge from the hospital.     

Enhancement of axillary brachial plexus block anesthesia by coadministration of neostigmine.

BACKGROUND AND OBJECTIVES: The acetylcholinesterase inhibitor neostigmine has shown peripherally mediated analgesic action in recent preclinical and clinical studies. The present study investigates the effectiveness of adding neostigmine to a local anesthetic, mepivacaine, in patients receiving axillary brachial plexus block for upper extremity surgery. METHODS: In a double-blind, randomized study 34 patients were assigned to the treatment group: Neostigmine (NM) (500 microg) + mepivacaine (M) (500 mg) (NM, n = 17) as drugs for the plexus block, or to control group: mepivacaine (500 mg) + saline (0.9%, 1 mL) (M, n = 17). RESULTS: The onset and duration of sensory and motor block was similar in both groups. Patients receiving NM had significantly lower pain ratings [visual analogue scores (VAS): 14.7 +/- 9.9 vs 32.4 +/-23.5; P < .05] 24 hours after surgery, and a lower number of patients in the NM group needed supplemental analgesics during the first 24 hours postoperatively. No adverse events were recorded for either group. CONCLUSIONS: Peripherally administered neostigmine improves postoperative analgesia in axillary brachial plexus block.     

The efficacy of continuous fascia iliaca compartment block for pain management in burn patients undergoing skin grafting procedures

Postoperative pain from split skin donor sites is often more intense than the pain at the grafted site. In this prospective, randomized, double-blind study we assessed the efficacy of a continuous fascia iliaca compartment block (FICB) in reducing the pain at the thigh donor site. Twenty patients, with a total burn surface area of 16% +/- 13% (mean +/- SD) were randomized 1:1 to receive either ropivacaine 0.2% or saline 0.9%. All patients received a general anesthesic followed by preincision continuous FICB with 40 mL of the randomized solution, then an infusion of 10 mL/h of either ropivacaine or saline until the first dressing change (72 h later). Postoperative analgesia consisted of propacetamol 2g/6h, IV patient-controlled analgesia of morphine chlorhydrate (2 mg/mL), and morphine hydrochlorate 0.5 mg/kg PO once 60 min before first dressing change. The visual analog scale (VAS) scores were compared using the Mann-Whitney U-test preoperatively, 24 and 48 h postoperatively, and during the first dressing change. The cumulative morphine consumption was compared with repeated-measures analysis of variance followed by Scheffé's method if indicated. Patients with continuous FICB had significantly reduced postoperative morphine consumption at all time points (23 +/- 20 versus 88 +/- 29 mg after 72 h, study versus control groups, respectively; P < 0.05). In both groups, VAS scores remained low but were only significantly lower for patients with continuous FICB during the first dressing change (3 [1] versus 7 [3]; median [interquartile range]; P < 0.05). We conclude that continuous FICB is an efficient method for diminishing pain at the thigh donor site. (250 words) IMPLICATIONS:Postoperative pain at the split skin donor sites is often more intense than the pain at the grafted site. This prospective, randomized, double-blind study assessed the efficacy of a continuous fascia iliaca compartment block in reducing the pain at the thigh donor site.