Pain relief and motor function during continuous interscalene analgesia after open shoulder surgery: a prospective, randomized, double-blind comparison between levobupivacaine 0.25%, and ropivacaine 0.25% or 0.4%

BACKGROUND AND OBJECTIVES: To compare pain relief and motor impairment of 0.25% levobupivacaine with either an equivalent (0.25%) or equipotent (0.4%) concentration of ropivacaine for continuous interscalene block after open shoulder surgery. METHODS: Seventy-two adult patients scheduled for elective major shoulder surgery received an interscalene injection of mepivacaine 1.5% 30 mL followed by 24 h patient-controlled interscalene analgesia (basal infusion rate: 5 mL h-1; incremental bolus: 2 mL; lockout period: 10 min; maximum boluses per hour: 4) with either 0.25% levobupivacaine (n = 24), 0.25% ropivacaine (n = 24) or 0.4% ropivacaine (n = 24). A blinded observer recorded the evolution of pain relief and recovery of motor block during the first 24 h. Motor function was assessed as the maximum pressure developed while squeezing a sphygmomanometer cuff with the blocked hand. The reduction from preoperative values was considered as an index of motor impairment. RESULTS: No differences were reported among the three groups in the quality of postoperative analgesia. The number of incremental patient-controlled interscalene analgesia doses, total volume of local anaesthetic infused during the 24-h patient-controlled interscalene analgesia, and number of rescue ketoprofen analgesia were higher in the ropivacaine 0.25% group than in the other two groups (P = 0.0005). The hand strength recovered to >or=90% of baseline values within the first 24 h of infusion in all groups, without differences among the three groups. CONCLUSION: When providing patient-controlled interscalene analgesia after open shoulder surgery 0.25% levobupivacaine and 0.4% ropivacaine performed equally in terms of pain relief, motor block and number of patient-controlled boluses required, while patients receiving 0.25% ropivacaine needed significantly more boluses and rescue analgesia to control their pain.     

A randomised comparison of variable‐frequency automated mandatory boluses with a basal infusion for patient‐controlled epidural analgesia during labour and delivery

This trial was conducted to compare the analgesic efficacy of administering variable‐frequency automated boluses at a rate proportional to the patient's needs with fixed continuous basal infusion in patient‐controlled epidural analgesia (PCEA) during labour and delivery. We recruited a total of 102 parturients in labour who were randomly assigned to receive either a novel PCEA with automated mandatory boluses of 5 ml administered once, twice, three or four times per hour depending on the history of the parturient's analgesic demands over the past hour (Automated bolus group), or a conventional PCEA with a basal infusion of 5 ml.h^?1 (Infusion group). The incidence of breakthrough pain requiring supplementation by an anaesthetist was significantly lower in the Automated bolus group, three out of 51 (5.9%) compared with the Infusion group, 12 out of 51 (23.5%, p = 0.023). The time‐weighted mean (SD) hourly consumption of ropivacaine was similar in both groups, 10.0 (3.0) mg in the Automated bolus group vs 11.1 (3.2) mg in the Infusion group (p = 0.06). Parturients from the Automated bolus group reported higher satisfaction scores compared with those in the Infusion group, 96.5 (5.0) vs 89.2 (9.4), respectively (p < 0.001). There was no difference in the incidence of maternal side‐effects and obstetric and neonatal outcomes.     

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

BACKGROUND AND OBJECTIVS: 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.     

Programmed intermittent epidural bolus vs. patient-controlled epidural analgesia for maintenance of labour analgesia: a two-centre,double-blind,randomised study†

The programmed intermittent epidural bolus technique has shown superiority to continuous epidural infusion techniques, with or without patient-controlled epidural analgesia for pain relief, reduced motor block and patient satisfaction. Many institutions still use patient-controlled epidural analgesia without a background infusion, and a comparative study between programmed intermittent epidural bolus and patient-controlled epidural analgesia without a background infusion has not yet been performed. We performed a randomised, two-centre, double-blind, controlled trial of these two techniques. The primary outcome was the incidence of breakthrough pain requiring a top-up dose by an anaesthetist. Secondary outcomes included: motor block; pain scores; patient satisfaction; local anaesthetic consumption; and obstetric and neonatal outcomes. We recruited 130 nulliparous women who received initial spinal analgesia, and then epidural analgesia was initiated and maintained with either programmed intermittent epidural bolus or patient-controlled epidural analgesia using ropivacaine 0.12% with sufentanil 0.75 µg·ml^-1. The programmed intermittent epidural bolus group had a programmed bolus of 10 ml every hour, with on-demand patient-controlled epidural analgesia boluses of 5 ml with a 20 min lockout, and the patient-controlled epidural analgesia group had a 5 ml bolus with a 12 min lockout interval; the potential maximum volume per hour was the same in both groups. The patients in the programmed intermittent epidural bolus group had less frequent breakthrough pain compared with the patient-controlled epidural analgesia group, 7 (10.9%) vs. 38 (62.3%; p < 0.0001), respectively. There was a significant difference in motor block (modified Bromage score ≤ 4) frequency between groups, programmed intermittent epidural bolus group 1 (1.6%) vs. patient-controlled epidural analgesia group 8 (13.1%); p = 0.015. The programmed intermittent epidural bolus group had greater local anaesthetic consumption with fewer patient-controlled epidural analgesia boluses. Patient satisfaction scores and obstetric or neonatal outcomes were not different between groups. In conclusion, we found that a programmed intermittent epidural bolus technique using 10 ml programmed boluses and 5 ml patient-controlled epidural analgesia boluses was superior to a patient-controlled epidural analgesia technique using 5 ml boluses and no background infusion.     

Patient-controlled interscalene analgesia with ropivacaine after major shoulder surgery: PCIA vs PCA

We have compared the efficacy of patient-controlled interscalene analgesia (PCIA) using ropivacaine with patient-controlled analgesia (PCA) using nicomorphine in 60 patients (n = 30 in each group), in a prospective, randomized study. In both groups, all patients received interscalene block with 0.75% ropivacaine before induction of anaesthesia. Six hours after interscalene block, patients in group PCIA received continuous infusion of 0.2% ropivacaine at a rate of 5 ml h-1 with a bolus dose of 3 or 4 ml and a lockout time of 20 min; patients in group PCA received continuous infusion of nicomorphine 0.5 mg h-1 and a bolus dose of 2 or 3 mg with a lockout time of 20 min. Control of pain was significantly better from 12 to 48 h after operation (except at 42 h) in group PCIA. Nausea and pruritus occurred significantly more frequently in group PCA. Patient satisfaction was greater in group PCIA. We conclude that the use of 0.2% ropivacaine using PCIA was an efficient way of managing pain after major shoulder surgery and compared favourably with PCA nicomorphine in terms of pain relief, side effects and patient satisfaction.      

Lidocaine versus ropivacaine for continuous interscalene brachial plexus block after open shoulder surgery

BACKGROUND: This study compared the postoperative infusion of 1% lidocaine and 0.2% ropivacaine for continuous interscalene analgesia in patients undergoing open shoulder surgery. METHODS: Forty patients undergoing open shoulder surgery received an interscalene brachial plexus block with 30 ml of either 1.5% lidocaine (n = 20) or 0.5% ropivacaine (n = 20), followed by a continuous patient-controlled interscalene analgesia with 1% lidocaine or 0.2% ropivacaine, respectively. A blinded observer recorded the quality of analgesia and recovery of motor function during the first 24 h of infusion. RESULTS: Onset of the block occurred after 7.5 (5-40) min with lidocaine and 30 (10-60) min with ropivacaine (P = 0.0005). Postoperative pain intensity was higher with lidocaine than ropivacaine for the first 8 h of infusion. The ratio between boluses given and demanded from the pump was 0.5 (0.13-0.7) with lidocaine and 0.7 (0.4-1.0) with ropivacaine (P = 0.005). Rescue IV tramadol was required during the first 24 h of infusion by 16 patients of the lidocaine group (84%) and eight patients of the ropivacaine group (46%) (P = 0.05). At the 16 h and 24 h observation times a larger proportion of patients receiving ropivacaine had complete regression of motor block (70% and 95%) than patients receiving lidocaine (50% and 55%) (P = 0.05 and P = 0.013, respectively). CONCLUSIONS: Although 1% lidocaine can be effectively used for postoperative patient-controlled interscalene analgesia, 0.2% ropivacaine provides better pain relief and motor function.     

Automated intermittent bolus infusion for continuous sciatic nerve block: a case report

We present two cases of severe pain due to critical limb ischemia (CLI) treated with automated intermittent bolus infusion for continuous sciatic nerve blocks. Case 1: A 32-year-old man had severe lower extremity ischemic pain due to Fontaine grade IV peripheral vascular disease. The pain did not respond to systemic analgesics. A popliteal nerve catheter was placed under ultrasound guidance. After confirming the effect of continuous infusion of ropivacaine from the catheter unsatisfactory, automated intermittent with patient-controlled bolus administration was started. His pain was controlled well. Case 2: A 52-year-old man had severe foot pain due to Buerger's disease. Bypass surgery and angioplasty failed to improve his symptoms. Even after the amputation of superficial fibular nerve, deep fibular nerve and tibial nerve, his pain persisted. The continuous popliteal sciatic nerve block was started. As continuous infusion did not relieve his pain, automated intermittent with patient-controlled bolus administration was started. However even with this technique, his pain was not relieved well. In some patients whose severe pain due to CLI could not be managed well, automated intermittent bolus infusion of local anesthetics from peripheral nerve catheter may provide better analgesia than continuous infusion.     

High-volume patient-controlled epidural vs. programmed intermittent epidural bolus for labour analgesia: a randomised controlled study

The aim of neuraxial analgesia is to achieve excellent pain relief with the fewest adverse effects. The most recently introduced technique for epidural analgesia maintenance is the programmed intermittent epidural bolus. In a recent study, we compared this with patient-controlled epidural analgesia without a background infusion and found that a programmed intermittent epidural bolus was associated with less breakthrough pain, lower pain scores, higher local anaesthetic consumption and comparable motor block. However, we had compared 10 ml programmed intermittent epidural boluses with 5 ml patient-controlled epidural analgesia boluses. To overcome this potential limitation, we designed a randomised, multicentre non-inferiority trial using 10 ml boluses in each group. The primary outcome was the incidence of breakthrough pain and total analgesic intake. Secondary outcomes included motor block; pain scores; patient satisfaction; and obstetric and neonatal outcomes. The trial was considered positive if two endpoints were met: non-inferiority of patient-controlled epidural analgesia with respect to breakthrough pain; and superiority of patient-controlled epidural analgesia with respect to local anaesthetic consumption. A total of 360 nulliparous women were allocated randomly to patient-controlled epidural analgesia-only or programmed intermittent epidural bolus groups. The patient-controlled group received 10 ml boluses of ropivacaine 0.12% with sufentanil 0.75 μg.ml^-1; the programmed intermittent group received 10 ml boluses supplemented by 5 ml patient-controlled boluses. The lockout period was 30 min in each group and the maximum allowed hourly local anaesthetic/opioid consumption was identical between the groups. Breakthrough pain was similar between groups (11.2% patient controlled vs. 10.8% programmed intermittent, p = 0.003 for non-inferiority). Total ropivacaine consumption was lower in the PCEA–group (mean difference 15.3 mg, p < 0.001). Motor block, patient satisfaction scores and maternal and neonatal outcomes were similar across both groups. In conclusion, patient-controlled epidural analgesia is non-inferior to programmed intermittent epidural bolus if equal volumes of patient-controlled epidural analgesia are used to maintain labour analgesia and superior with respect to local anaesthetic consumption.     

Patient-controlled interscalene analgesia with ropivacaine 0.2% versus bupivacaine 0.15% after major open shoulder surgery: the effects on hand motor function

We compared the effects of patient-controlled interscalene analgesia with ropivacaine 0.2% and patient-controlled interscalene analgesia (PCIA) with bupivacaine 0.15% on hand grip strength after major open shoulder surgery. Sixty patients scheduled for elective major shoulder surgery were prospectively randomized to receive in a double-blinded fashion either ropivacaine or bupivacaine through an interscalene catheter. Before surgery, all patients received an interscalene block (ISB) with either 40 mL of 0.6% ropivacaine or 40 mL of 0.5% bupivacaine. Six h after ISB, the patients received a continuous infusion of either 0.2% ropivacaine or 0.15% bupivacaine for 48 h. In both groups, the PCIA infusion rate was 5 mL/h plus a bolus of 4 mL with a lockout time of 20 min. Strength in the hand was assessed preoperatively, 24 h, and 48 h after ISB and 6 h after stopping the infusion of local anesthetic. The presence of paresthesia in the fingers was checked. Pain relief was assessed using a visual analog scale; side effects were noted, and the patients rated their satisfaction 54 h after the block. A significant decrease of strength in the hand was observed in the Bupivacaine group 24, 48, and 54 h after ISB (P < 0.05). Paresthesia was more frequently reported in the Bupivacaine group for the second and third fingers 48 h after ISB (P < 0.05) and in the first three fingers 6 h after discontinuation of the local anesthetic infusion (P: < 0.05). The pain score was similar in the two groups at all times, and patient satisfaction was comparable between the two groups. We conclude that the use of the PCIA technique with ropivacaine 0.2% or bupivacaine 0.15% provides a similar pain relief after major shoulder surgery. However, ropivacaine 0.2% is associated with better preservation of strength in the hand and less paresthesia in the fingers. Implications: We compared the patient-controlled interscalene analgesia technique with ropivacaine 0.2% and bupivacaine 0.15% after major open shoulder surgery. For similar pain control ropivacaine is associated with better preservation of strength in the hand and less paresthesia in the fingers.     

Patient-controlled interscalene analgesia with ropivacaine 0.2% versus patient-controlled intravenous analgesia after major shoulder surgery: effects on diaphragmatic and respiratory function

BACKGROUND: The authors compared the effects of patient-controlled interscalene analgesia (PCIA) with ropivacaine 0.2% and patient-controlled intravenous analgesia (PCIVA) with opioids on hemidiaphragmatic excursion and respiratory function after major shoulder surgery. METHODS: Thirty-five patients scheduled for elective major shoulder surgery were prospectively randomized to receive either PCIA or PCIVA. All patients received an interscalene block before surgery. In the PCIA group, a catheter was introduced between the anterior and middle scalene muscles. Six hours after the initial block, patients received for 48 h either a continuous infusion of 0.2% ropivacaine through the interscalene catheter at a rate of 5 ml/h plus a bolus dose of 3 or 4 ml with a lockout time of 20 min (PCIA group) or a continuous intravenous infusion of nicomorphine at a rate or 0.5 mg/h plus a bolus dose of 2 or 3 mg with a lockout time of 20 min (PCIVA group). Hemidiaphragmatic excursion and respiratory function were assessed with the patient in a 45 degrees semirecumbent position the day before the operation and 20 min (in the operating room), 24 h, and 48 h after the initial block by means of ultrasonography and spirometry, respectively. Pain relief was regularly assessed, side effects were noted, and patient satisfaction was rated 6 h after the end of the study. RESULTS: Hemidiaphragmatic excursion was similar in the two groups 20 min after interscalene block. Hemidiaphragmatic excursion was increased in the PCIA group on the nonoperated side 24 and 48 h after the interscalene block (P < 0.05). Pulmonary function was similar in the two groups at each time. Pain was better controlled in the PCIA group at 12 and 24 h (P < 0.05). The incidence of nausea and vomiting were 5.5% versus 60% for the PCIA and PCIVA groups, respectively (P < 0.05). Patient satisfaction was greater in the PCIA group (P < 0.05). CONCLUSIONS: The use of PCIA or PCIVA techniques to provide analgesia after major shoulder surgery is associated with similar effects on respiratory function. In the PCIA group, hemidiaphragmatic excursion showed a significantly greater amplitude 24 and 48 h after the initial block on the nonoperated side. The PCIA technique provided better pain control, a lower incidence of side effects, and a higher degree of patient satisfaction.     

Interscalene brachial plexus anesthesia and analgesia for open shoulder surgery: a randomized,double-blinded comparison between levobupivacaine and ropivacaine

We compared the onset time and quality of interscalene brachial plexus block produced with levobupivacaine and ropivacaine in 50 patients undergoing open shoulder surgery randomly allocated to receive 30 mL of 0.5% levobupivacaine (n = 25) or 0.5% ropivacaine (n = 25) injected through a 20-gauge catheter placed into the interscalene sheath using a 18-gauge insulated and stimulating Tuohy introducer. The block was also prolonged after surgery using a patient-controlled interscalene analgesia with 0.125% levobupivacaine or 0.2% ropivacaine, respectively (basal infusion rate, 6 mL/h; bolus, 2 mL; lockout period, 15 min; maximum boluses per hour, three). Three patients (two with levobupivacaine [8%] and one with ropivacaine [4%]) failed to achieve surgical block within 45 min after the injection and were excluded. The onset time of surgical block was 20 min (10-40 min) with levobupivacaine and 20 min (5-45 min) with ropivacaine (P = 0.53). Rescue intraoperative analgesia (0.1 mg of fentanyl IV) was required in eight patients in each group (34%) (P = 0.99). Forty-two patients completed the 24-h postoperative infusion (22 with levobupivacaine and 20 with ropivacaine). Postoperative analgesia was similarly effective in both groups. Total consumption of local anesthetic infused during the first 24 h was 147 mL (144-196 mL) with levobupivacaine and 162 mL (144-248 mL) with ropivacaine (P = 0.019), with a ratio between boluses received and requested of 0.8 (0.4-1.0) and 0.7 (0.4-1.0), respectively (P = 0.004). The degree of motor block of the operated limb was deeper with levobupivacaine than ropivacaine when starting postoperative analgesia; however, no further differences in degree of motor function were observed between the two groups. We conclude that 30 mL of levobupivacaine 0.5% induces an interscalene brachial plexus anesthesia of similar onset and intensity as the one produced by the same volume and concentration of ropivacaine. Postoperative interscalene analgesia with 0.125% levobupivacaine results in similar pain relief and recovery of motor function with less volume of local anesthetic than with 0.2% ropivacaine. IMPLICATIONS: This prospective, randomized, double-blinded study demonstrates that 30 mL of 0.5% levobupivacaine produces an interscalene brachial plexus block of similar onset and quality as the one produced by the same volume of 0.5% ropivacaine. When prolonging the block after surgery, 0.125% levobupivacaine provides adequate pain relief and recovery of motor function after open shoulder surgery, with less volume infused during the first 24 h after surgery than 0.2% ropivacaine.     

Patient-controlled Interscalene Analgesia with Ropivacaine 0.2%Versus Patient-controlled Intravenous Analgesia after Major Shoulder Surgery: Effects on Diaphragmatic and Respiratory Function

Background: The authors compared the effects of patient-controlled interscalene analgesia (PCIA) with ropivacaine 0.2% and patient-controlled intravenous analgesia (PCIVA) with opioids on hemidiaphragmatic excursion and respiratory function after major shoulder surgery.

Methods: Thirty-five patients scheduled for elective major shoulder surgery were prospectively randomized to receive either PCIA or PCIVA. All patients received an interscalene block before surgery. In the PCIA group, a catheter was introduced between the anterior and middle scalene muscles. Six hours after the initial block, patients received for 48 h either a continuous infusion of 0.2% ropivacaine through the interscalene catheter at a rate of 5 ml/h plus a bolus dose of 3 or 4 ml with a lockout time of 20 min (PCIA group) or a continuous intravenous infusion of nicomorphine at a rate or 0.5 mg/h plus a bolus dose of 2 or 3 mg with a lockout time of 20 min (PCIVA group). Hemidiaphragmatic excursion and respiratory function were assessed with the patient in a 45[degrees] semirecumbent position the day before the operation and 20 min (in the operating room), 24 h, and 48 h after the initial block by means of ultrasonography and spirometry, respectively. Pain relief was regularly assessed, side effects were noted, and patient satisfaction was rated 6 h after the end of the study.

Results: Hemidiaphragmatic excursion was similar in the two groups 20 min after interscalene block. Hemidiaphragmatic excursion was increased in the PCIA group on the nonoperated side 24 and 48 h after the interscalene block (P < 0.05). Pulmonary function was similar in the two groups at each time. Pain was better controlled in the PCIA group at 12 and 24 h (P < 0.05). The incidence of nausea and vomiting were 5.5%versus 60% for the PCIA and PCIVA groups, respectively (P < 0.05). Patient satisfaction was greater in the PCIA group (P < 0.05).     

Clonidine added to a continuous interscalene ropivacaine perineural infusion to improve postoperative analgesia: a randomized, double-blind, controlled study

Although clonidine has been shown to increase the duration of local anesthetic action and prolong postoperative analgesia when included in single-injection nerve blocks, the only controlled investigation of the efficacy of this practice to improve analgesia for continuous perineural local anesthetic infusion failed to discern any clinically relevant benefits. For this study, we used a larger dose of clonidine in an attempt to improve analgesia. Patients (n = 20) undergoing moderately painful orthopedic surgery of the shoulder received an interscalene brachial plexus block (40 mL of mepivacaine 1.5%, epinephrine 2.5 microg/mL, and clonidine 50 microg) and a perineural catheter before surgery. After surgery, ropivacaine 0.2% or ropivacaine 0.2% plus clonidine 2 microg/mL was delivered via the catheter for 3 days (basal rate, 5 mL/h; patient-controlled bolus, 5 mL; lockout, 1 h). Investigators and patients were blind to random group assignment. The primary outcome variable was designated as the most intense pain during the day after surgery. Secondary end-points included additional pain scores, patient-controlled bolus doses, oral analgesic use, sleep quality, and catheter- or infusion-related complications. There were no statistically significant differences between groups for any of the variables investigated. We conclude that adding clonidine 2 microg/mL to a ropivacaine interscalene perineural infusion does not decrease breakthrough pain intensity the day after surgery. For the additional end-points, our negative findings are only suggestive of a lack of effect and require further study for verification.     

Continuous interscalene analgesia with ropivacaine 2 mg/ml after major shoulder surgery

BACKGROUND: In this open, randomized study, the pharmacokinetics, clinical efficacy, and safety of a 48-h continuous interscalene infusion of 2 mg/ml ropivacaine for postoperative pain relief were investigated in patients undergoing open major shoulder surgery. METHODS: An initial interscalene block with 30 ml ropivacaine, 7.5 mg/ml (225 mg), was performed. After completion of interscalene block, all patients (n = 24) received general anesthesia, and 6 h after interscalene block, a 48-h continuous interscalene infusion of 12 or 18 mg/h using 2 mg/ml ropivacaine was started. Total and unbound plasma concentrations of ropivacaine and 2.6-pipecoloxylidide (PPX; a major active metabolite) were determined during and up to 6 h after the interscalene infusion. Postoperative pain at rest was assessed by a visual analog scale. Supplementary analgesics and adverse events were recorded. RESULTS: Plasma concentrations of total and unbound ropivacaine were proportional to the total dose. At the end of the interscalene infusion of 9 ml/h, the mean +/- SD plasma concentrations of total and unbound ropivacaine were 1.40 +/- 0.54 and 0.03 +/- 0.01 mg/l, respectively, and of total and unbound PPX were 0.70 +/- 0.38 and 0.30 +/- 0.20 mg/l, respectively. Plasma concentrations of unbound ropivacaine and unbound PPX, added together, remained well below threshold levels for systemic central nervous system toxicity. There were no significant differences between the groups for postoperative pain (median maximum of about 20 mm on the visual analog scale in both groups), analgesic consumption, or quality of pain relief assessed by the patient. No signs or symptoms of systemic local anesthetic toxicity were observed. CONCLUSION: A 48-h continuous interscalene infusion of 6 or 9 ml/h ropivacaine, 2 mg/ml, started 6 h after an initial interscalene block of 30 ml ropivacaine, 7.5 mg/ml, provided satisfactory postoperative pain relief after major shoulder surgery and was well tolerated. Unbound plasma concentrations of ropivacaine and PPX remained well below threshold levels for systemic central nervous toxicity.     

Interscalene brachial plexus analgesia after open shoulder surgery: continuous versus patient-controlled infusion.

In this prospective, randomized, double-blinded study, we assessed the efficacy of patient-controlled analgesia (PCA) for continuous interscalene analgesia after open shoulder surgery. Sixty patients were divided into three groups of 20. During a 48-h period, they received, via an interscalene catheter, a continuous infusion of 0.125% bupivacaine with sufentanil 0.1 microg/mL and clonidine 1 microg/mL at 10 mL /h in Group 1; a continuous infusion of the same solution at 5 mL/h plus PCA boluses (2.5 mL/30 min) in Group 2; and only PCA boluses (5 mL/30 min) of the same solution in Group 3. Pain scores, sensory block, supplemental analgesia, bupivacaine consumption, side effects, and satisfaction scores were recorded. At 24 and 48 h, sensory block was more frequent and pain control was significantly better in Groups 1 and 2 than in Group 3 (P < 0.001). In Group 3, larger doses of paracetamol were required. Bupivacaine consumption was significantly less in Groups 2 and 3 than in Group 1 (P < 0.001). Satisfaction was significantly higher in Groups 1 and 2 than in Group 3 (P < 0.01). Side effects were comparable in the three groups. We conclude that continuous interscalene analgesia requires a background infusion after open shoulder surgery. Because it reduces the local anesthetic consumption and allows the patients to rapidly reinforce the block shortly before physiotherapy, a basal infusion rate of 5 mL/h combined with PCA boluses (2.5 mL/ 30 min) is the recommended technique. IMPLICATIONS: In this study, we demonstrated that continuous interscalene analgesia requires a background infusion to provide efficient pain relief after open shoulder surgery. A basal infusion of 5 mL/h combined with patient-controlled analgesia boluses (2.5 mL/30 min) seems to be the most appropriate technique.     

Analgesia requirements after interscalene block for shoulder arthroscopy: the 5 days following surgery

Introduction  

Excellent initial post-operative analgesia for patients undergoing arthroscopic shoulder surgery can be provided with a single-shot interscalene brachial plexus block. However there have been concerns that when the block wears off, patients may experience pain and this may occur at home. Some investigators have advocated the use of continuous ambulatory local anaesthetic infusions following hospital discharge. We prospectively studied pain scores, analgesic requirements and satisfaction of patients at home in the first 5 days following arthroscopic shoulder surgery to see whether continuous infusion would be of benefit.     

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.     

Patient-controlled Analgesia after Major Shoulder Surgery: Patient-controlled Interscalene Analgesia versus Patient-controlled Analgesia

Background: The authors compared patient-controlled interscalene analgesia (PCIA) with local anesthetics with intravenous patient-controlled analgesia (PCA) with opioids to manage postoperative pain after major shoulder surgery.

Methods: Forty patients scheduled for elective major shoulder surgery were prospectively randomized to receive either PCIA or PCA. Before surgery, all patients had an interscalene block. In the PCIA group, a catheter was introduced within the interscalene sheath. Six hours after the initial block, patients received for 48 h either a continuous infusion of 0.15% bupivacaine through the interscalene catheter at a rate of 5 ml/h plus a bolus of 3 or 4 ml with a lock-time of 20 min (group PCIA) or a continuous intravenous infusion of nicomorphine at a rate of 0.5 mg/h plus a bolus of 2 or 3 mg with a lock-time of 20 min (group PCA). Pain relief was regularly assessed using a visual analog scale, side effects were noted, and the patients were asked to rate their satisfaction at the end of the study.

Results: Pain relief was significantly better controlled in the PCIA group at t = 12 and 18 h (P < 0.05). Vomiting and pruritus were 0 versus 25% and 0 versus 25% for the PCIA and PCA groups, respectively (P < 0.05). Patient satisfaction was greater in the PCIA group (P < 0.05). Time of first bolus administration and paracetamol supplement were similar in both groups.     

Contralateral local anesthetic spread from an outpatient interscalene catheter

Purpose

Ambulatory continuous infusions have been associated with improved analgesia and few serious complications. This report describes an unusual case of a patient with a continuous interscalene nerve block who developed a contralateral upper extremity sensory block. The complication did not occur until postoperative day two while the patient was at home.

Clinical features

A 56-yr-old woman had a continuous interscalene catheter placed for arthroscopic lysis of adhesions of her shoulder. The insertion needle was initially injected with 0.5% ropivacaine 25 mL (1:400,000 epinephrine), producing a unilateral interscalene block. Postoperatively, the patient was started on a continuous interscalene infusion of 0.2% ropivacaine at 8 mL·hr^?1 via a disposable infusion pump. The next day, the patient had a unilateral brachial plexus block and an associated Horner’s syndrome and was discharged home with the infusion. On the morning of the second postoperative day, the patient developed ipsilateral and contralateral Horner’s syndrome with associated numbness in both shoulders. The catheter was removed and symptoms resolved four hours later.

Conclusions

Ambulatory continuous infusions are typically associated with few serious complications and a favourable safety profile. This case demonstrates that unexpected complications can still occur even after days of normal operation. Based on our previous experience, we believe this to be a rare but potentially serious event that requires awareness by those discharging patients with continuous infusions of local anesthetics.     

Postoperative analgesia for shoulder surgery: a critical appraisal and review of current techniques

Shoulder surgery is well recognised as having the potential to cause severe postoperative pain. The aim of this review is to assess critically the evidence relating to the effectiveness of regional anaesthesia techniques commonly used for postoperative analgesia following shoulder surgery. Subacromial/intra‐articular local anaesthetic infiltration appears to perform only marginally better than placebo, and because the technique has been associated with catastrophic chondrolysis, it can no longer be recommended. All single injection nerve blocks are limited by a short effective duration. Suprascapular nerve block reduces postoperative pain and opioid consumption following arthroscopic surgery, but provides inferior analgesia compared with single injection interscalene block. Continuous interscalene block incorporating a basal local anaesthetic infusion and patient controlled boluses is the most effective analgesic technique following both major and minor shoulder surgery. However, interscalene nerve block is an invasive procedure with potentially serious complications and should therefore only be performed by practitioners with appropriate experience.