Effectiveness of ropivacaine and fentanyl for postoperative epidural analgesia following thoracic surgery

BACKGROUND: Epidural ropivacaine is now a common drug used for postoperative analgesia. However, little information is available concerning regression of sensory blockade and analgesia following prolonged epidural infusion of ropivacaine. We investigated the efficacy of ropivacaine and fentanyl for postoperative analgesia after thoracic surgery. METHODS: Thirty patients undergoing thoracic surgery were enrolled. After surgery with general and thoracic epidural anesthesia, continuous epidural infusion of 0.2% ropivacaine+fentanyl (1.67 microg x ml(-1)) was started at a rate of 6 ml x h(-1) for patients whose height was more than 155 cm and 4 ml x h(-1) for those below 155 cm with possibility of an additional bolus injection of 3 ml at least every 60 min. RESULTS: An additional epidural injection of 3 ml produced a decrease in VAS without significant changes of vital signs. The greatest VAS was 10+/-25 mm in the incision site and 36+/-38 mm in the ipsilateral shoulder. Sensory blockade was sustained until the morning after the day of surgery. Also blood pressure and heart rate were stable throughout the observation period. There were no adverse effects except for slight nausea in three patients. CONCLUSIONS: A bolus of 3 ml with continuous 4-6 ml x h(-1) epidural injection of ropivacaine plus a small dose of fentanyl would decrease postoperative pain with stable vital signs in patients after thoracic surgery.     

Efficacy of ropivacaine, bupivacaine, and levobupivacaine for labor epidural analgesia

STUDY OBJECTIVE: To compare analgesic efficacy and intensity of motor block with continuous infusions of ropivacaine, bupivacaine, and levobupivacaine in combination with fentanyl for labor epidural analgesia. DESIGN: Prospective, randomized, double-blinded study. SETTING: Labor and delivery suite at Magee Womens Hospital, Pittsburgh, PA. PATIENTS: 162 ASA physical status I and II, full-term, primiparous women. INTERVENTIONS: All patients received epidural labor analgesia. Epidural medication consisted of an initial bolus of 8 mL local anesthetic with fentanyl (100 microg) followed by an infusion at 12 mL/h of local anesthetic with 2 microg/mL fentanyl. Patients were allocated to one of three groups, as follows: group 1 received bolus and infusion of bupivacaine 0.125%, group 2 received bolus and infusion of levobupivacaine 0.125%, and group 3 received a bolus of ropivacaine 0.2% and infusion of ropivacaine 0.1%. MEASUREMENTS: Maternal vital signs, pain visual analog scale (VAS) score, sensory levels, and motor block (Bromage score) were recorded every hour. Duration of first and second stage of labor and mode of delivery were also recorded. RESULTS: There were no statistically significant differences in pain VAS or Bromage motor scores among the three groups of patients at any of the measured time intervals. The time to achieve T10 sensory level and patient comfort was shorter in the ropivacaine (9.35 +/- 4.96 min) and levobupivacaine (9.56 +/- 4.71 min) groups than the bupivacaine (11.89 +/- 7.76 min) group, although this difference did not reach a statistically significant level (P = 0.06). The second stage was significantly shorter in the bupivacaine group, lasting 81.27 +/- 63.3 min, compared with the ropivacaine group (121.69 +/- 86.5 min) and the levobupivacaine (115.5 +/- 83.6 minutes) group (P = 0.04). CONCLUSION: There are no significant differences in pain VAS and Bromage scores between 0.1% ropivacaine, 0.125% bupivacaine, and 0.1% levobupivacaine given for labor epidural analgesia.     

Postoperative analgesia using continuous lumbar epidural infusion of ropivacaine in comparison with bupivacaine

BACKGROUND: Epidural bupivacaine infusion is a commonly used technique for postoperative analgesia because of its motor-sparing properties. Recently a new long acting local anesthetic, ropivacaine, has become available. The aim of this study was to investigate the efficacy of ropivacaine and bupivacaine with regard to postoperative analgesia when administered continuously into the lumbar epidural space. METHODS: All patients were ASA I II and undergoing ipsi-lateral leg orthopedic surgery with epidural or combined spinal-epidural anesthesia. Patients were randomly assigned to following three groups: 0.1% ropivacaine (0.1 R); 0.2% ropivacaine (0.2 R); 0.125% bupivacaine (0.125 B). At the end of surgery, continuous infusion was begun at a rate of 6 ml.hr 1 after a bolus epidural administration of 5 ml of 0.2% ropivacaine in R groups and 0.25% bupivacaine in B group. Sensory and motor block, blood pressure, pulse rate, verbal pain score (VPS), analgesic consumption were assessed at 20 min, 1, 3, 10-20 hrs following the beginning of continuous infusion. RESULTS: Vital signs were stable at every measuring point in all groups. In 0.1 R group (n = 20), the spread of sensory block at 3 hrs after infusion was lower than 0.2 R group (n = 19), and VPS during the study was higher than 0.125 B group (n = 17). Bromage scale after 3 hrs was higher in 0.2 R group compared with 0.125 B group. The degree of sensory and motor block gradually decreased, resulting in little difference between the groups. When epidural anesthesia was spread over the surgical area throughout the study, 0.2 R or 0.125 B was sufficiently relieved from postoperative pain. CONCLUSIONS: After leg orthopedic surgery, 6 ml.hr-1 of 0.2 R or 0.125 B provided enough postoperative analgesia when the spread of anesthesia covered the operated area. 0.2 R would be better compared to 0.125 B in continuous epidural infusion for postoperative analgesia due to less systemic toxicity, even though it accompanies a little more intense motor block.     

Postoperative analgesia by combined continuous infusion and patient-controlled epidural analgesia (PCEA) following hip replacement: ropivacaine versus bupivacaine

BACKGROUND: Ropivacaine is a new local anaesthetic, which compared to bupivacaine is less toxic and shows greater sensory and motor block dissociation. We hypothesised that treatment of postoperative pain with a combined regimen of continuous epidural infusion and Patient-Controlled Epidural Analgesia (PCEA) using ropivacaine could have given better results compared with those we had obtained using bupivacaine. METHODS: Patients undergoing total hip replacement were randomly assigned to two groups. They received epidural analgesia for postoperative pain treatment using ropivacaine, 2 mg x ml(-1) or bupivacaine 2 mg x ml(-1). Both drugs were administered as a constant infusion of 6 ml x h(-1) supplemented by PCEA bolus doses of 2 ml. Patients in both groups received morphine intravenously on demand from a patient-controlled analgesia (PCA) device. An independent observer recorded pain scores, intensity of motor block and morphine consumption at regular intervals during the first 24 h after surgery. RESULTS: Fifty-one patients were evaluated. Ropivacaine and bupivacaine, in similar amounts, provided similar results assessed as adequate to very good postoperative analgesia, whereas motor block was significantly more intense in patients treated with bupivacaine. CONCLUSIONS: Despite similar analgesic effects, epidural infusion of ropivacaine combined with PCEA provides higher patient satisfaction than equal doses of bupivacaine due to lack of motor block.     

A randomized,double-blinded comparison of thoracic epidural ropivacaine,ropivacaine/fentanyl,or bupivacaine/fentanyl for postthoracotomy analgesia

Epidural ropivacaine has not been compared with bupivacaine for postthoracotomy analgesia. Eighty patients undergoing elective lung surgery were randomized in a double-blinded manner to receive one of three solutions for high thoracic epidural analgesia. A continuous epidural infusion of 0.1 mL. kg(-1). h(-1) of either 0.2% ropivacaine, 0.15% ropivacaine/fentanyl 5 micro g/mL, or 0.1% bupivacaine/fentanyl 5 micro g/mL was started at admission to the intensive care unit. We assessed pain scores (rest and spirometry), IV morphine consumption, spirometry, hand grip strength, PaCO(2), heart rate, blood pressure, respiratory rate, and side effects (sedation, nausea, vomiting, and pruritus) for 48 h. Thoracic epidural ropivacaine/fentanyl provided adequate pain relief similar to bupivacaine/fentanyl during the first 2 postoperative days after posterolateral thoracotomy. The use of plain 0.2% ropivacaine was associated with worse pain control during spirometry, larger consumption of IV morphine, and increased incidence of postoperative nausea and vomiting. Morphine requirements were larger in the ropivacaine group, with no differences between bupivacaine/fentanyl and ropivacaine/fentanyl groups. Patients in the ropivacaine group experienced more pain and performed worse in spirometry than patients who received epidural fentanyl. There was no significant difference in motor block. We conclude that epidural ropivacaine/fentanyl offers no clinical advantage compared with bupivacaine/fentanyl for postthoracotomy analgesia. IMPLICATIONS: Thoracic epidural ropivacaine/fentanyl provided adequate pain relief and similar analgesia to bupivacaine/fentanyl during the first 2 postoperative days after posterolateral thoracotomy. Plain 0.2% ropivacaine was associated with worse pain control and an increased incidence of postoperative nausea and vomiting. We conclude that epidural ropivacaine/fentanyl offers no clinical advantage compared with bupivacaine/fentanyl for postthoracotomy analgesia.     

Comparison of ropivacaine 0.1%-fentanyl and bupivacaine 0.125% — fentanyl infusions for epidural labour analgesia

PURPOSE: To compare analgesic efficacies of ropivacaine-fentanyl and bupivacaine-fentanyl infusions for labour epidural analgesia. METHODS: In this double- blind, randomized study 100, term, nulliparous women were enrolled. Lumbar epidural analgesia (LEA) was started at cervical dilatation < 5 cm using either bupivacaine 0.25% followed by bupivacaine 0.125% + 2 microg x ml(-1) fentanyl infusion (n=50) or ropivacaine 0.2% followed by ropivacaine 0.1% + 2 microg x ml(-1) fentanyl infusion (n=50). Every hour maternal vital signs, visual analog scale (VAS) pain score, sensory levels, and motor block (Bromage score) were assessed. Data were expressed as mean +/-1 SD and analyzed using Chi -Squared and Mann-Whitney U tests at <0.05. RESULTS: The onset times were 10.62+/-4.9 and 11.3+/-4.7 min for the bupivacaine and ropivacaine groups respectively (P = NS). The median VAS scores were not different between the groups at any of the evaluation periods. However, at least 80% of patients in the ropivacaine group had no demonstrable motor block after the first hour compared with only 55% of patients given bupivacaine (P =0.01). CONCLUSIONS: Both bupivacaine and ropivacaine produce satisfactory labour analgesia. However, ropivacaine infusion is associated with less motor block throughout the first stage of labour and at 10 cm dilatation.     

Epidural fentanyl delayed emergence from anesthesia

An 83-year-old man (158 cm, 42 kg) was scheduled for cholecystectomy. He had a history of hypertension and atrial fibrillation. The patient received no premedication. An epidural catheter was inserted via the T9-10 interspace and 2% mepivacaine 7 ml was injected, producing a sensory block from T4 to T12. Anesthesia was induced with propofol and remifentanil, and was maintained with propofol, remifentanil, and nitrous oxide in oxygen. Rocuronium was given to provide neuromuscular block. Just before the completion of surgery, a bolus epidural injection of 2% mepivacaine 2 ml with fentanyl 50 microg was performed. Then epidural solution of ropivacaine 0.1% with fentanyl 6.25 microg x ml(-1), and droperidol 25 microg x ml(-1) was infused at 4 ml x hr(-1). Soon after the surgery, the patient developed atrial fibrillation that was treated with external electrocardioversion with 100 watt x sec. After the restoration of sinus rhythm, anesthetics were discontinued. The patient did not emerge from anesthesia though he breathed spontaneously Doxapram was slightly effective, but he did not respond to the verbal command. Epidural infusion was stopped and the patient was transferred to the ward. The patient fully recovered from anesthesia after 2 hours. Epidural infusion was restarted 17 hours later, and the patient fell asleep. He woke up after stopping epidural infusion. Epidurally administered fentanyl must have been the cause of delayed recovery from anesthesia. He could have been highly sensitive to fentanyl. Patient controlled epidural anesthesia may have been useful for this patient.     

Patient supplemented epidural analgesia after major abdominal surgery with bupivacaine/fentanyl or ropivacaine/fentanyl

PURPOSE: To compare analgesic efficacy and occurrence of motor block and other side effects during patient supplemented epidural analgesia (PSEA) with either ropivacaine/fentanyl or bupivacaine/fentanyl mixtures. METHODS: In a prospective, randomized, double-blind study, 32 ASAI-III patients undergoing major abdominal surgery received an epidural catheter at the T8- T10, followed by integrated general epidural anesthesia. Postoperative epidural analgesia was provided using a patient controlled pump with either ropivacaine 0.2%/2 microg x ml(-1) fentanyl (group Ropivacaine, n = 16) or bupivacaine 0.125%/2 microg x ml(-1) fentanyl (group Bupivacaine, n = 16) [background infusion 4-6 ml x hr(-1), 1.5 ml Incremental Doses and 20 min lock out]. Verbal pain rating score, number of incremental doses, consumption of epidural analgesic solution and rescue analgesics, sedation (four-point scale), and pulse oximetry were recorded by a blind observer for 48 hr after surgery. RESULTS: No differences in pain relief, motor block, degree of sedation, pulse oximetry and other side effects were observed between the two groups. The number of incremental doses and the volume of analgesic solution infused epidurally were higher in patients receiving the bupivacaine/fentanyl mixture (10 [0-52] I.D. and 236 [204-340] ml) than in patients receiving the ropivacaine/fentanyl solution (5 [0-50] I.D. and 208 [148-260] ml) (P = 0.03 and P = 0.05, respectively). CONCLUSION: Using a ropivacaine 0.2%/2 microg x ml(-1) fentanyl mixture for patient supplemented epidural analgesia after major abdominal surgery provided similar successful pain relief as bupivacaine 0.125%/2 microg x ml(-1) fentanyl, but patients receiving bupivacaine/fentanyl requested more supplemental.     

Study of analgestic efficacy of ropivacaine-fentanyl patient-controlled epidural analgesia after upper abdominal gynecological surgery

BACKGROUND: Most of the patients who undergo radical or subradical hysterectomy with paraaortic lymphadenectomy suffer from postoperative pain for upper abdominal incision. They also complain of postoperative nausea and vomiting (PONV) frequently, which are increased by opioids. METHODS: Reducing total fentanyl dose to 0.6 mg, frequency of moving pain complaints increased gradually. Therefore, we introduced patient-controlled epidural analgesia (PCEA) for suppressing pain on moving. We investigated analgestic efficacy of 0.2% ropivacaine-fentanyl PCEA in twelve patients undergoing upper abdominal gynecological surgery. Postoperative analgesic effects were evaluated by visual analogue scale (VAS) at rest and on moving, times of bolus infusion, side effects, and degrees of satisfication by patient's self-assessments. Continuous epidural infusion of 0.6 mg fentanyl in 288 ml 0.2% ropivacaine was started at a rate of 4 ml x hr(-1) with a bolus dose of 2 ml. RESULTS: VAS was maintained below 20 mm at rest but was elevated to the maximum of 45 mm on moving with few bolus requests. Ninty-two percents of the patients answered satisfied but fifty percents of them had PONV. CONCLUSIONS: We conclude that ropivacaine-fentanyl PCEA is effective after upper abdominal gynecological surgery, and we can decrease the dose of fentanyl by explaining PCEA system more effectively to the patients for suppressing the pain on moving and PONV.     

Epinephrine markedly improves thoracic epidural analgesia produced by a small-dose infusion of ropivacaine,fentanyl, and epinephrine after major thoracic or abdominal surgery: a randomized,double-blinded crossover study with and without epinephrine

We have shown that epinephrine markedly improves the analgesic effect of a thoracic epidural infusion of bupivacaine and fentanyl. Ropivacaine has an intrinsic vasoconstrictive effect, and epinephrine may therefore not have the same pharmacokinetic interaction in a ropivacaine-fentanyl infusion; but a possible spinal cord alpha(2)-agonist effect of epinephrine would give the same positive pharmacodynamic interaction with ropivacaine and fentanyl during epidural analgesia. In a prospective, randomized, crossover study, a thoracic epidural infusion of ropivacaine 1 mg/mL and fentanyl 2 microg/mL with or without epinephrine 2 microg/mL was given to 12 patients in a double-blinded manner after major thoracic or upper abdominal surgery. Main outcome measures were pain intensity at rest and when coughing, evaluated on a visual analog scale. Extent of sensory blockade was evaluated by determining dermatomal hypoesthesia to cold. Pain increased (P < 0.001) and hypoesthetic dermatomal segments decreased (P < 0.001) when epinephrine was omitted from the triple epidural infusion. After 3 h without epinephrine, pain intensity when coughing was unacceptable despite rescue analgesia. After restarting the triple epidural mixture with epinephrine, pain was again reduced to mild pain when coughing, and the sensory blockade was restored. The mixture with epinephrine caused less nausea and facilitated mobilization. We conclude that epinephrine improves the pain relief and reduces the side effects of a thoracic epidural infusion of ropivacaine and fentanyl after major thoracic or upper abdominal surgery. IMPLICATIONS: Epidural epinephrine markedly improves the pain relief and sensory blockade of a small-dose thoracic epidural infusion of ropivacaine and fentanyl. Nausea was reduced, and mobilization of the patients was facilitated.     

Comparison of ropivacaine and bupivacaine for epidural analgesia during labor]

OBJECTIVES: To compare the analgesic efficacy and level of motor block using two local anesthetics, ropivacaine and bupivacaine, during labor. MATERIAL AND METHODS: Sixty nulliparous women were enrolled during labor after full-term pregnancies. They were randomly assigned to receive epidural analgesia with ropivacaine (group R) or bupivacaine (group B). Group R patients received 10 ml of 0.18% ropivacaine with 5 microgram/ml of fentanyl followed by continuous epidural infusion of 0.1% ropivacaine with 2 microgram/ml of fentanyl at a rate of 10 ml/h. Group B patients received 10 ml of 0.15% bupivacaine with 5 microgram/ml of fentanyl followed by continuous epidural perfusion of 0.0625% bupivacaine with 2 microgram/ml of fentanyl at the same rate. Pain intensity was assessed on a visual analog scale, motor blockade on a Bromage scale, and level of sensory block at different moments. We also recorded total doses of local anesthetic employed during continuous epidural infusion, manner of final delivery, Apgar score, degree of maternal satisfaction and side effects. RESULTS: The demographic and delivery characteristics were similar in both groups. We found no statistically significant differences between the two groups for level of motor blockade, which was nil for 29 patients (96.66%) in group R and 28 patients (93.33%) in group B. No differences in degree of pain or level of sensory block (T8-T10 in both groups) were observed.The total doses of local anesthetic used were similar at 23.7 +/- 11.6 mg in group R and 16.5 +/- 7.3 mg in group B (non-significant difference). Nor did we find differences in manner of delivery, neonatal Apgar scores, degree of maternal satisfaction or side effects. CONCLUSION: Ropivacaine and bupivacaine are equally effective for epidural analgesia during labor at the doses used and they do not cause a relevant level of motor blockade.     

The effect of continuous epidural infusion of ropivacaine (0.1%, 0.2% and 0.3%) on nerve conduction velocity and postural control in volunteers

Background: Continuous epidural infusions of local anaesthetics have become increasingly popular in postoperative pain treatment, especially as they permit early mobilisation. Ropivacaine is a promising new agent which induces more pronounced sensory than motor blockade. This study was focused on the influence of continuous epidural infusion of ropivacaine on impulse conduction in large nerves (by measurement of F and H latencies), and on the subjects' ability to maintain postural control during mobilisation. Methods: Healthy male volunteers received 0.1%, 0.2% or 0.3% ropivacaine, and bupivacaine 0.25% was used as reference. A bolus epidural injection of 10 ml of the drug, at L2/3 level, was followed by continuous infusion at 10 ml/h for 21 h. Motor blockade was assessed by mechanical measurements of force during big toe flexion and by recording of F latency. Sensory blockade was monitored by pin-prick and Thermotest methods, and by H latency recording. The subjects' ability to perform a postural test was evaluated by posturography. Results: The F and H latencies became prolonged/abolished dose-dependently. With ropivacaine, F latency recovered significantly later than motor function (P = 0.0002), and H latency recovered later than normal pin-prick perception (P = 0.0006). However, the duration of partial blockade of thermopercep-tion was comparable to that of H latency prolongation. Posturographically, the subjects receiving 0.1% ropivacaine differed significantly from all others (P<0.001) in that they were able to maintain postural control during the infusion. The recovery period after termination of infusion was significantly shorter with ropivacaine than with bupivacaine for all measured variables. Conclusion: Recovery of postural control with 0.2% and 0.3% ropivacaine is significantly faster than with bupivacaine 0.25%. H latency recording allows detection of epidural blockade intensity that does not prevent subjects from performing postural tests.     

Fentanyl added to bupivacaine 0.05% or ropivacaine 0.05% in patient-controlled epidural analgesia in labour

BACKGROUND AND OBJECTIVE: Epidural analgesia is the most effective method for pain relief during labour. The aim was to elucidate the efficacy of ropivacaine 0.05% and bupivacaine 0.05%, which were both combined with fentanyl 0.00015% to provide analgesia in labour. METHODS: Forty nulliparous females were enrolled into the study. After insertion of an epidural catheter, patients were randomly assigned into two groups. Once the os uteri had dilated to 4-5 cm, a bolus of bupivacaine 0.125% 10mL + fentanyl 50 microg (1 mL) in Group 1 patients, and ropivacaine 0.125% 10mL + fentanyl 50 microg (1 mL) in Group 2 patients was administered via the epidural catheter. Then, patient-controlled epidural analgesia was started with a basal infusion of bupivacaine 0.05% 10 mLh(-1) + fentanyl 0.00015% 1.5 pgmL(-1) in Group 1, and ropivacaine 0.05% + fentanyl 1.5 microgmL(-1) in Group 2. When needed, a 10 mL bolus infusion could be given and the lockout time was 20 min. Maternal and fetal haemodynamic variables were monitored before induction and subsequently at 5 min intervals. Using a visual analogue scale assessed the degree of pain. RESULTS: Maternal haemodynamic variables and Apgar scores were not different between the two groups. The second stage of the labour was shorter in Group 2 (P < 0.01). There were no significant differences in patients' assessment of motor block or mode of delivery between groups. CONCLUSIONS: An epidural infusion (10 mLh(-1)) of bupivacaine 0.05% or ropivacaine 0.05% together with fentanyl 1.5 microg mL(-1) provided good and safe analgesia during labour.     

Horner syndrome and brachial plexus blockade after epidural anesthesia for obstetric labor and cesarean section

A 30-year-old woman (ASA II, obese) in her 40th week of a first pregnancy required epidural analgesia for labor. When the cervix had dilated to 5 cm, the epidural infusion was started with a 9-mL bolus of 0.2% ropivacaine and 50 pg of fentanyl, after a negative test dose. An infusion of 0.2% ropivacaine and 1 microg/mL of fentanyl was started at a rate of 8 mL/h. A cesarean section was required after insufficient progress was made during 8 hours of labor. Eight milliliters of 0.75% ropivacaine was administered to provide anesthesia to T4; cesarean delivery was completed without complications. Early during postoperative recovery, in addition to motor blockade of the legs, the patient experienced a right brachial plexus blockade and Horner syndrome on the same side. Both effects disappeared spontaneously (1 and 4 hours later, respectively).     

Anesthetic management for the minimally invasive Nuss procedure in 21 patients with pectus excavatum

The aim of this study was to assess the anesthetic management and postoperative analgesic effect of continuous epidural infusion for the minimally invasive Nuss procedure. A total of 21 operated cases were analyzed retrospectively. Thoracoscopy was used in all cases. General anesthesia with endotracheal intubation was induced and maintained with oxygen, air, sevoflurane, and fentanyl in all cases. Thoracic epidural anesthesia was performed after induction at the level between Th4 and 12. When the bar was placed via insertion under the sternum, six patients exhibited sinus tachycardia and one showed premature atrial contraction for 2–4 beats before recovering spontaneously within 1 min. Operations were uneventful. The mean operating time was 115 min and anesthetic time was 193 min. In X-ray findings, residual pneumothorax and pleural effusion were found in seven (33.3%) and eight (38.0%) patients, respectively. In all cases, these symptoms were resolved spontaneously within 5 days. Epidural fentanyl (0.3 μg·kg⁻¹·h⁻¹) in 0.125% bupivacaine (0.15 ml·kg⁻¹·h⁻¹) or 0.2% ropivacaine (0.15 ml·kg⁻¹·h⁻¹) were used for 3 days to relieve postoperative pain. Postoperatively, 12 (57.1%) patients required no additional analgesics, and 4 (19.0%) patients required a single dose of dicrofenac sodium or pentazocine. Although the Nuss procedure is minimally invasive, we should pay attention to the possibility of many intra- and postoperative complications. Continuous epidural infusion of fentanyl with local anesthetics provides effective postoperative pain relief and prevents complications such as bar displacement after the Nuss procedure.     

Quantitative methodological studies of motor and sensory blockade in epidural analgesia with special reference to early mobilization and a new local anesthetic — ropivacaine

Abstract: In six studies of epidural analgesia, sensory and motor blockade caused by ropivacaine and bupivacaine was evaluated by quantitative methods. The dose response to single injections of high (0.5%,0.75% and 1%) and low concentrations (0.1%, 0.2% and 0.3%) of ropivacaine in continuous infusion was investigated. Motor blockade was measured by mechanotransducers and by average rectified electromyography. The presence of residual effects was determined by F response and H reflex recording. Quantitative methods for assessment of sensory blockade (Thermotest method, argon laser stimulation and recording of somatosensory evoked potentials - SEPs) were introduced with 0.5% bupivacaine. A selection of these quantitative methods was applied during continuous epidural infusion (21 h) of ropivacaine. Mobilization was attempted throughout the infusion period. In ambulant subjects, postural control was evaluated by posturography. Motor blockade with high concentrations of ropivacaine was dose-dependent, but only in segments close to the injection site (L2/3). In the abdominal muscles, the blockade was partial and not clearly dose-dependent. Persistent prolongation of H reflex latency was found in five subjects who received high concentrations of ropivacaine, but not in any of those receiving continuous infusion. With 0.5% bupivacaine the zone of anesthesia was smaller, and the zone of partial blockade of thermo- and laser-perception larger than that of the pin-prick analgesia. There were no significant differences in the spatial or temporal sequence of blockade between the Thermotest and laser stimulation methods. Changes in SEPs caused by epidural blockade with bupivacaine could not distinguish between the sensory blockade of low and high intensity. During continuous infusion of 0.1% ropivacaine, motor blockade was so slight that all subjects could be mobilized, whereas with 0.2% and 0.3% ropivacaine it was moderate (40–50% of baseline force was present). The zone of analgesia was smaller with 0.1% ropivacaine than with 0.2% and 0.3% solutions. With 0.1% ropivacaine the subjects were able to perform postural tests and maintain balance, which was not the case with 0.2% and 0.3% ropivacaine. A quick recovery after discontinuation of infusion was characteristic of ropivacaine.     

Neurological deficit following lumbar epidural anesthesia with ropivacaine

A 38-year-old woman with placenta previa was scheduled for cesarean section. She had no abnormal medical history including neurological deficit before the operation. Prior to general anesthesia, an epidural catheter was inserted in the L2-3 interspace for postoperative analgesia. There was no difficulty in threading the catheter. No pain, paresthesia or bleeding was elicited at any time. After a test dose of 1% lidocaine 1 ml, a bolus of 0.75% ropivacaine 12 ml was injected through the epidural catheter. At the end of the operation, a continuous epidural infusion of 0.2% ropivacaine (the pump speed of 6 ml x h(-1)) was started. On the second postoperative day, sudden sensory loss level to L2 (right lower extremity), L3 (left one) and flaccid paralysis of bilateral lower extremities occurred. MRI and myelogram showed no abnormality of the spinal cord. Her neurological deficit showed slight improvement but her sensory and motor paralysis still remained. Neurotoxicity of ropivacaine may be the cause of this neurological deficit.     

Intraoperative epidural anesthesia and postoperative analgesia with levobupivacaine for major orthopedic surgery: a double-blind,randomized comparison of racemic bupivacaine and ropivacaine

STUDY OBJECTIVE: To compare the onset time and duration of epidural anesthesia, and the quality of postoperative analgesia produced by levobupivacaine, racemic bupivacaine, and ropivacaine. DESIGN: Prospective, randomized, double-blinded study. SETTING: Inpatient anesthesia at a University Hospital. PATIENTS: 45 ASA physical status I, II, and III patients, undergoing elective total hip replacement. INTERVENTIONS: After standard intravenous midazolam premedication and infusion of 500 mL of Ringer's acetate solution, patients were randomly allocated to receive epidural block with 0.5% levobupivacaine (n = 15), 0.5% bupivacaine (n = 15), or 0.5% ropivacaine (n = 15). Postoperatively, after pinprick sensation recovered at T(t), a patient-controlled epidural infusion was provided with 0.125% levobupivacaine, 0.125% bupivacaine, or 0.2% ropivacaine, respectively (baseline infusion rate 5 mL/hr; incremental bolus 2 mL, lockout time: 20 min). Intravenous ketoprofen was also available for rescue analgesia if required. MEASUREMENTS AND MAIN RESULTS: The onset time of sensory block was 31 +/- 16 minutes with levobupivacaine, 25 +/- 19 minutes with bupivacaine, and 30 +/- 24 minutes with ropivacaine (p = 0.98), after a median (range) volume of 15 (10-18) mL in Group Levobupivacaine, 14 (10-18) mL in Group Bupivacaine, and 15 (10-18) mL in Group Ropivacaine (p = 0.85). Six patients in the ropivacaine group (40%) showed an intraoperative Bromage score <2 as compared with only three patients of Group Levobupivacaine (20%) and no patient of Group Bupivacaine (p = 0.02). Recovery of pinprick sensation at T(t) occurred after 214 +/- 61 minutes with levobupivacaine, 213 +/- 53 minutes with bupivacaine, and 233 +/- 34 minutes with ropivacaine (p = 0.26). A similar degree of pain relief was observed in the three groups without differences in local anesthetic consumption and need for rescue analgesia. Motor blockade progressively resolved without differences among the three groups. CONCLUSIONS: Levobupivacaine 0.5% produces an epidural block of similar onset, quality, and duration as the one produced by the same volume of 0.5% bupivacaine, with a motor block deeper than that produced by 0.5% ropivacaine. When prolonging the block for the first 12 hours after surgery with a patient-controlled epidural infusion, 0.125% levobupivacaine provides adequate pain relief after major orthopedic surgery, with similar recovery of motor function as compared with 0.125% bupivacaine and 0.2% ropivacaine.     

Epidural fentanyl markedly improves thoracic epidural analgesia in a low-dose infusion of bupivacaine, adrenaline and fentanyl. A randomized, double-blind crossover study with and without fentanyl

BACKGROUND: The objectives of the present study were to evaluate the effects on postoperative pain intensity, pain relief, and side effects when removing fentanyl from an optimally titrated epidural infusion consisting of bupivacaine, fentanyl and adrenaline. METHODS: A prospective, randomized, double-blind, crossover study was carried out in 20 patients after major upper abdominal surgery requiring a large longitudinal incision. Patients with only mild pain when coughing during thoracic epidural infusion of about 10 ml per hour of bupivacaine 1 mg x ml(-1), fentanyl 2 microg x ml(-1), and adrenaline 2 microg x ml(-1) were included. On the 1st and 2nd postoperative days, each patient was given a double-blind epidural infusion, at the same rate, with or without fentanyl. The effects were observed for 6 h or until pain when coughing became unacceptable in spite of rescue analgesia. Rescue analgesia consisted of up to two patient-controlled epidural bolus injections (4 ml) per hour and intravenous morphine if necessary. RESULTS: Main outcome measures, i.e. pain intensity when coughing and at rest, increased (P<0.001) when fentanyl (19.2+/-5.2 microg x h(-1)) was omitted from the epidural infusion: after 6 h pain intensity when coughing had increased to unacceptable levels in spite of increased consumption of rescue bupivacaine and adrenaline (P<0.001). Within 15-20 min after restarting the triple epidural mixture with fentanyl, pain intensity was again reduced to mild pain when coughing. CONCLUSIONS: A low dose of epidural fentanyl (20 microg x h(-1)) markedly improved the pain-relieving effect of bupivacaine and adrenaline infused epidurally at a thoracic level after major upper abdominal surgery. This dose of fentanyl is much too small to relieve severe dynamic pain when given systemically. Therefore, this study indirectly supports the view that a low-dose thoracic epidural infusion of fentanyl has a spinal analgesic site of action.     

Ropivacaine 0.1% with fentanyl 2 microg mL(-1) by epidural infusion for labour analgesia

BACKGROUND AND OBJECTIVE: To evaluate the efficacy of 0.1% ropivacaine with fentanyl 2 microg mL(-1) via epidural for analgesia in labour. METHODS: In a randomized study, 80 nulliparous parturients in labour had epidural analgesia initiated with 0.2% ropivacaine and fentanyl and were then randomized to receive either 0.1% ropivacaine with fentanyl 2 microg mL(-1) at 10mL h(-1) (Group R1, n = 38) or 0.2% ropivacaine with fentanyl 2 microg mL(-1) at 8 ml h(-1) (Group R2, n = 39) as epidural infusions. Supplementary analgesia was provided on request with ropivacaine 0.2% 5 mL as an epidural bolus. RESULTS: There were no significant differences between the visual analogue pain scores either with respect to motor block or sensory block. The amount of local anaesthetic used was lower in the 0.1% ropivacaine group than in the 0.2% ropivacaine group (P = 0.001). Side-effects, patient satisfaction, labour outcome and neonatal outcomes were similar in both groups. CONCLUSIONS: An epidural infusion of 0.1% ropivacaine with fentanyl 2 microg mL(-1) at 10 mL h(-1) provided adequate analgesia in the first stage of labour. The level of analgesia was similar to that obtained using 0.2% ropivacaine with fentanyl 2 microg mL(-1) and with no differences with regard to motor or sensory block.