Continuous epidural infusion of ropivacaine for the prevention of postoperative pain after major orthopaedic surgery: a dose-finding study

Comparison of Efficacy of Epidural Ropivacaine versus Bupivacaine for Postoperative Pain Relief in Total Knee Replacement Surgeries

Background:

Epidural analgesia has become the standard of care for knee replacement surgeries worldwide. Bupivacaine has been used successfully for many years. Epidural ropivacaine is now being used increasingly and seems to have benefits other than just pain relief, in terms of a better safety profile.

Aim:

To compare the efficacy of bupivacaine 0.125% (Group B) versus two concentrations of ropivacaine 0.1% (Group R1) and 0.2% (Group R2), in terms of pain scores, requirement of rescue analgesia, related adverse effects, and duration of postoperative (PO) hospital stay.

Materials and Methods:

A retrospective study was conducted from the acute pain service data of patients who underwent joint replacement surgeries in one or both limbs, over a span of 6 months. Patients were allocated to and analyzed under one of the three groups based on the drug concentration used postoperatively by epidural infusion. Data retrieved were demographic data, daily average visual analog scale (VAS) pain scores, rescue analgesia given, adverse effects, and PO hospital stay days for all three groups.

Results:

Demographic data were comparable between the three groups. Daily average VAS pain scores on days 1 and 2 were significantly higher in Group R1. Groups B and R2 were comparable. There was significantly more requirement of rescue analgesia in Group R1 on day 1. Day 2 showed no significant difference in rescue analgesic requirement in all three groups. Days of PO hospital stay were significantly higher in Group R1. Adverse effects such as hypotension and delayed motor block were higher in Group B.

Conclusion:

Ropivacaine 0.2% and bupivacaine 0.125% were equally efficacious in terms of VAS pain scores, rescue analgesic requirement, and duration of PO hospital stay, but ropivacaine had a better safety profile in terms of less hypotension and lesser motor block.

A Randomized Double Blinded Comparison of Epidural Infusion of Bupivacaine, Ropivacaine, Bupivacaine-Fentanyl, Ropivacaine-Fentanyl for Postoperative Pain Relief in Lower Limb Surgeries

BACKGROUND

Continuous epidural infusion of Bupivacaine and Ropivacaine with or without the addition of Fentanyl has been evaluated by various researchers for effective postoperative pain relief. Studies however, depict significant variability in their results with regard to analgesic efficacy and adverse effects like hypotension, motor blockade etc.

AIM

To comparatively evaluate postoperative analgesic efficacy, motor sparing effect, postoperative haemodynamic variations and total postoperative analgesic consumption in first 24 hours.

MATERIALS AND METHODS

A randomised double blind study was conducted on 100 adult, ASA grade I and II patients, of either sex who had undergone elective lower limb surgery under spinal anaesthesia. According to the group allocated, patients were started on epidural infusion after completion of surgery. Group I (0.2% Ropivacaine), Group II (0.1% Ropivacaine + 2μg/ml Fentanyl), Group III (0.2% Bupivacaine), Group IV (0.1% Bupivacaine + 2μg/ml Fentanyl) at the rate of 6 ml/hour. VAS scores, epidural consumption, supplemental epidural boluses, rescue analgesics, haemodynamics, motor block, sensory block regression, sedation, nausea and pruritis were recorded by a blinded observer for 24 hours.

RESULTS

The haemodynamic parameters were stable in all the groups. Side effects including the motor block were negligible and comparable in all groups. Group I patients had significantly lower VAS scores, mean total epidural consumption, supplemental epidural bolus requirement and rescue analgesic requirement among all groups.

CONCLUSION

It can be concluded that epidural analgesia using Ropivacaine 0.2% infusion is more effective than other study groups when used for postoperative pain relief in lower limb surgeries.

Epidural ropivacaine infusion for the treatment of pain following axillary muscle-sparing thoracotomy: a dose-evaluation study

PURPOSE

We aimed to investigate the optimal dose of continuous epidural ropivacaine for effective analgesia with minimal side effects after axillary muscle-sparing thoracotomy.

METHODS

Sixty patients undergoing thoracic surgery via the axillary approach were studied. Patients were given continuous epidural ropivacaine at 6 (group R-6), 9 (group R-9), 12 (group R-12) or 18 mg x h(-1) (group R-18) in a randomized double-blinded fashion after surgery. All of the patients received nonsteroidal anti-inflammatory drugs (NSAIDs) every 6 h for 24 h postoperatively. Pain intensity was assessed under three conditions (at rest, on moving, and while coughing), at 4, 8, 16, 24, and 48 h after surgery, and the extent of sensory block was evaluated at the same time points. The ability of a patient to walk unaided was assessed at 24 and 48 h after surgery.

RESULTS

Pain intensity at rest and coughing was significantly higher in group R-6 than in the other groups at 16 h after surgery. Pain intensity during moving was significantly greater in group R-6 than in groups R-12 and R-18 at 16 h after surgery. Group R-18 exhibited a significantly greater extent of sensory block than the other groups. The number of patients who were not able to walk unaided 24 h after surgery was significantly greater in group R-18. There were no significant differences in the incidences of side effects among the groups.

CONCLUSION

Our results showed that epidural analgesia using ropivacaine, at 12 mg x h(-1), provided the best analgesia with few side effects.

A Comparison of Three Different Concentrations of Ropivacaine with Fentanyl for Patient-Controlled Epidural Analgesia

BACKGROUND

The optimal concentration of ropivacaine in combination with fentanyl for patient-controlled epidural analgesia focusing on preservation of bowel function, analgesia, and motor function remains unclear.

METHODS

Three hundred-twelve women scheduled to undergo gynecologic lower abdominal surgery, were randomly allocated to receive ropivacaine 0.05, 0.075, or 0.1% in combination with fentanyl 4 mug/mL and droperidol 25 microg/mL. The settings of patient-controlled epidural analgesia were as follows: initial loading volume 5 mL, background infusion 2 mL/h during night-time, no background infusion during daytime, bolus volume 2 mL, and lockout interval 10 min. Bowel function was evaluated by the first passage of flatus and feces. Pain was assessed with a visual analog scale, and motor function was examined by modified Bromage scale. Data were collected in the evening on the day of surgery, in the morning and in the evening on the first postoperative day, and in the morning on the second postoperative day.

RESULTS

Gastrointestinal motility was not different among the three groups. All three solutions produced equivalent analgesia and no motor blockade.

CONCLUSION

We conclude that ropivacaine 0.05% is sufficient to preserve gastrointestinal motility, and provides excellent postoperative pain relief without motor blockade.

Superiority of postoperative epidural over intravenous patient-controlled analgesia in orthopedic oncologic patients

BACKGROUND

Surgery for bone malignancy is associated with intense postoperative pain. Patient-controlled epidural analgesia (PCEA) and intravenous patient-controlled analgesia (IV-PCA) are used currently for postoperative pain control.

METHODS

The degree of pain control after resection of bone malignancy under combined general and epidural anesthesia followed postoperatively by prospectively randomized PCEA (ropivacaine 3.2 mg + fentanyl 8 microg/dose) or IV-PCA (morphine 2 mg/dose) (n = 35/group) was assessed. Postoperative analgesia delivery continued for up to 96 h; intramuscular rescue with diclofenac 75 mg was also available.

RESULTS

The mean hourly pain score among the PCEA patients was 3.0 +/- 0.9, compared with 4. 7 +/- 0.6 (P < .01) among the IV-PCA patients. All mean hourly pain scores in the PCEA patients, except for the first 2 hours of treatment, were less than 4/10, but they were higher in the IV-PCA patients. The demand for diclofenac was 2 times (n = 10) lower for the PCEA patients, compared with their IV counterparts (n = 20, P < .01); the same difference applied to the overall side effects (n = 15 vs n = 30, P < .01). Self-rated wakefulness and feelings of well-being were better in the PCEA patients.

CONCLUSIONS

Postoperative ropivacaine + fentanyl via PCEA reduces pain better and affords better subjective feelings than IV morphine via PCA after resection of bone malignancy carried out under combined general and epidural anesthesia.

Benefit-Risk Assessment of Ropivacaine in the Management of Postoperative Pain

Ropivacaine is a long-acting amide-type local anaesthetic, released for clinical use in 1996. In comparison with bupivacaine, ropivacaine is equally effective for subcutaneous infiltration, epidural and peripheral nerve block for surgery, obstetric procedures and postoperative analgesia. Nevertheless, ropivacaine differs from bupivacaine in several aspects: firstly, it is marketed as a pure S(-)-enantiomer and not as a racemate, and secondly, its lipid solubility is markedly lower. These features have been suggested to significantly improve the safety profile of ropivacaine, and indeed, numerous studies have shown that ropivacaine has less cardiovascular and CNS toxicity than racemic bupivacaine in healthy volunteers. Extensive clinical data have demonstrated that epidural 0.2% ropivacaine is nearly identical to 0.2% bupivacaine with regard to onset, quality and duration of sensory blockade for initiation and maintenance of labour analgesia. Ropivacaine also provides effective pain relief after abdominal or orthopaedic surgery, especially when given in conjunction with opioids or other adjuvants. Nevertheless, epidurally administered ropivacaine causes significantly less motor blockade at low concentrations. Whether the greater degree of blockade of nerve fibres involved in pain transmission (Adelta- and C-fibres) than of those controlling motor function (Aalpha- and Abeta-fibres) is due to a lower relative potency compared with bupivacaine or whether other physicochemical properties or stereoselectivity are involved, is still a matter of intense debate. Recommended epidural doses for postoperative or labour pain are 20-40 mg as bolus with 20-30 mg as top-up dose, with an interval of >or=30 minutes. Alternatively, 0.2% ropivacaine can be given as continuous epidural infusion at a rate of 6-14 mL/h (lumbar route) or 4-10 mL/h (thoracic route). Preoperative or postoperative subcutaneous wound infiltration, during cholecystectomy or inguinal hernia repair, with ropivacaine 100-175 mg has been shown to be more effective than placebo and as effective as bupivacaine in reducing wound pain, whereby the vasoconstrictive potency of ropivacaine may be involved. Similar results were found in peripheral blockades on upper and lower limbs. Ropivacaine shows an identical efficacy and potency to that of bupivacaine, with similar analgesic duration over hours using single shot or continuous catheter techniques. In summary, ropivacaine, a newer long-acting local anaesthetic, has an efficacy generally similar to that of the same dose of bupivacaine with regard to postoperative pain relief, but causes less motor blockade and stronger vasoconstriction at low concentrations. Despite a significantly better safety profile of the pure S(-)-isomer of ropivacaine, the increased cost of ropivacaine may presently limit its clinical utility in postoperative pain therapy.

[Use of ropivacaine for peridural postoperative analgesia]

OBJECTIVES

To describe pharmacology and toxicology of ropivacaine. To assess the clinical efficacy of ropivacaine when used for postoperative epidural analgesia and to provide recommendations for clinical practice.

DATA SOURCES

Search in the Medline data base of original articles in French and English published since 1995, using the following key words: ropivacaine, postoperative analgesia, epidural, caudal block.

STUDY SELECTION

Prospective randomised studies in adults and children were selected. Letters to editors and editorials were excluded.

DATA EXTRACTION

Articles have been analyzed: to determine the dose of ropivacaine required for postoperative epidural analgesia, to assess the benefits of combination of epidural ropivacaine and additives (opioids or other), to compare epidural ropivacaine and bupivacaine and to assess the use of ropivacaine via caudal route for paediatric postoperative analgesia.

DATA SYNTHESIS

20 mg h-1 of ropivacaine is required to provide effective analgesia. This dose produces a motor block in a significant number of patients. Combination with an opioid allows for a reduction in ropivacaine requirement and subsequently in the incidence of motor blockade. In adults, equipotency ratio of ropivacaine and bupivacaine varies between 1.5/1 and 1/1 depending upon the concentration used. At equipotent doses, early postoperative mobilisation is facilitated with ropivacaine. In case of paediatric caudal analgesia, this ratio is close to 1.

CONCLUSIONS

Epidural ropivacaine combined with opioid provide good postoperative pain relief. Reduction in the incidence of motor blockade and safe toxicological profile make this local anaesthetic a suitable alternative of bupivacaine for postoperative epidural analgesia.

Efficacy of ropivacaine compared with ropivacaine plus sufentanil for postoperative analgesia after major knee surgery

This study compared the analgesic efficacy of an epidural infusion of ropivacaine and ropivacaine with sufentanil following major knee surgery. In a double-blind clinical trial, 115 adult patients received either epidural ropivacaine (R group, 2 mg.ml(-1)), or ropivacaine (2 mg.ml(-1)) with sufentanil (RS group, 1 microg.ml(-1)), using a patient-controlled epidural analgesia technique. Pain scores (visual analogue scale, VAS, and the simple descriptive scale, SDS), side-effects, motor block and treatment quality were recorded at 6, 12 and 24 h after the insertion of the epidural catheter. In the RS group, analgesic efficacy was significantly greater than in the R group between 12 and 24 h following insertion of the epidural catheter (VAS: 92.9% vs. 72.9%, p = 0.009). There was no significant difference during the other periods. Pruritus, nausea and vomiting were significantly more frequent in the RS group. Good postoperative analgesia was obtained with an epidural infusion of ropivacaine (2 mg.ml(-1)). When this local anaesthetic was administered with sufentanil, there was an improvement in the analgesic effect but a significant increase in the number of patients who reported adverse effects. The differences were more pronounced 12 h after the beginning of the analgesic schedule. This study failed to demonstrate any worthwhile clinical benefit from the addition of sufentanil.

The efficacy and safety of three concentrations of levobupivacaine administered as a continuous epidural infusion in patients undergoing orthopedic surgery

We evaluated the efficacy and safety of three concentrations of levobupivacaine infused epidurally as analgesia for patients undergoing orthopedic procedures. Patients undergoing elective hip or knee joint replacement were enrolled in the study (n = 105). Sensory blockade was established preoperatively with 10-15 mL of 0.75% levobupivacaine. Patients were then randomized to receive 0.0625%, 0.125%, or 0.25% levobupivacaine as a continuous epidural infusion at 6 mL/h for 24 h. IV morphine patient-controlled analgesia was given as rescue analgesia, and time to first request for analgesia and total dose of morphine consumed were recorded. Sensory blockade, motor blockade, visual analog scale pain score, and cardiovascular variables were also recorded at regular intervals postoperatively. Ninety-one patients were included in the primary intent-to-treat analysis. Total normalized dose of morphine, number of patient-controlled analgesia requests, and overall postoperative visual analog scale pain scores were significantly lower for the 0.25% group compared with the other two groups, and the time to first request for rescue analgesia was longer. There was no significant difference between the 0.125% and 0.25% groups in terms of maximum motor blockade achieved and time to minimal motor blockade. Safety data were equivalent among the three groups. We conclude that levobupivacaine as a continuous epidural infusion provided adequate postoperative analgesia and that the 0.25% concentration provided significantly longer analgesia than 0.125% or 0.0625% levobupivacaine without any significant increase in detectable motor blockade relative to the 0.125% group.

IMPLICATIONS

Postoperative epidural infusion of levobupivacaine can provide safe and effective analgesia for patients having hip or knee joint replacement. Of the three concentrations we infused at a constant rate, 0.25% provided significantly better pain relief.

Minimizing perioperative adverse events in the elderly

Elderly patients still have the highest postoperative mortality and morbidity rate in the adult surgical population. Preoperative clinical assessment to detect patients at high risk of postoperative events, and specific intraoperative and postoperative anaesthesia management are important to minimize postoperative adverse events in the elderly.

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.

Prolonged epidural infusions of ropivacaine (2 mg/mL) after colonic surgery: the impact of adding fentanyl

We evaluated the safety and efficacy of a 72-h epidural infusion of ropivacaine and measured the impact of adding fentanyl 2 microg/mL to the required infusion rate, on the quality of postoperative pain relief and the incidence of side effects, after colonic surgery. One hundred fifty-five patients scheduled for elective colonic surgery were randomized in this trial. Epidural infusions of ropivacaine 2 mg/mL with fentanyl 2 microg/mL (R + F) and without fentanyl (R) were commenced during surgery and continued for 72 h postoperatively. This was a prospective, randomized, double-blinded, multi-center trial. The median infusion rate required was less in the R + F group (9.3 vs 11.5 mL/h, P < 0.001). Median pain scores at rest and on coughing were lower in the R + F group (P < 0.0001). The incidence of hypotension was more in the R + F group (P = 0.01). Time to readiness for discharge was delayed in the R + F group (median 6.6 vs 5.5 days, P = 0.012). The addition of fentanyl to ropivacaine resulted in decreased infusion rates and enhanced pain control; however, adverse effects were increased and readiness to discharge was delayed.

IMPLICATIONS

Epidural infusions of ropivacaine with and without fentanyl were administered to patients to control pain after colonic surgery. Patients who received ropivacaine with fentanyl had better pain control, increased side effects, and delayed readiness to discharge. This study questions the value of adding opioids to epidural infusions of local anesthetics.

Ropivacaine 1 mg x ml(-1) does not decrease the need for epidural fentanyl after hip replacement surgery

BACKGROUND

Ropivacaine is a new long-acting local anesthetic. Laboratory trials have demonstrated a synergistic analgesic effect between intrathecal opioids and local anesthetics. We tested the hypothesis that addition of ropivacaine 1 mg x ml(-1) to epidural fentanyl (10 microg x ml(-1)) postoperatively decreases the need for fentanyl, improves the quality of analgesia and decreases the side-effects of fentanyl.

METHODS

Forty patients were enrolled in this double-blind, randomized study to receive either fentanyl 10 microg x ml(-1) (group F) alone or fentanyl combined with ropivacaine 1 mg x ml(-1) (group R) for 20 h as an epidural infusion at TH12-L1 or L1-L2 for analgesia after hip replacement surgery. The patients were free to use a patient-controlled epidural analgesia device, which was programmed to infuse 3 ml of the study medication hourly and to allow a 3-ml bolus when needed (maximal hourly dose of fentanyl was 150 microg). The consumption of medication, visual pain scores at rest and on movement, hemodynamic and respiratory parameters, motor and sensory block, nausea, pruritus and sedation were recorded.

RESULTS

There were no significant differences between the groups in the total mean fentanyl consumption (1.10+/-0.18 mg in group F, 1.08+/-0.31 mg in group R, 95% CI: -0.14 to 0.19, P = 0.774). The pain scores were similar at rest (median scores < or = 1) and on movement (median scores < or = 3). The adverse effects were similar and of a minor nature, consisting mostly of pruritus and nausea.

CONCLUSION

Addition of ropivacaine 1 mg x ml(-1) to epidural fentanyl 10 microg x ml(-1) did not significantly decrease the requirement for fentanyl administered for pain relief after hip replacement surgery.

Ropivacaine: an update of its use in regional anaesthesia

Ropivacaine is a long-acting, enantiomerically pure (S-enantiomer) amide local anaesthetic with a high pKa and low lipid solubility which blocks nerve fibres involved in pain transmission (Adelta and C fibres) to a greater degree than those controlling motor function (Abeta fibres). The drug was less cardiotoxic than equal concentrations of racemic bupivacaine but more so than lidocaine (lignocaine) in vitro and had a significantly higher threshold for CNS toxicity than racemic bupivacaine in healthy volunteers (mean maximum tolerated unbound arterial plasma concentrations were 0.56 and 0.3 mg/L, respectively). Extensive clinical data have shown that epidural ropivacaine 0.2% is effective for the initiation and maintenance of labour analgesia, and provides pain relief after abdominal or orthopaedic surgery especially when given in conjunction with opioids (coadministration with opioids may also allow for lower concentrations of ropivacaine to be used). The drug had efficacy generally similar to that of the same dose of bupivacaine with regard to pain relief but caused less motor blockade at low concentrations. Lumbar epidural administration of 20 to 30ml ropivacaine 0.5% provided anaesthesia of a similar quality to that achieved with bupivacaine 0.5% in women undergoing caesarean section, but the duration of motor blockade was shorter with ropivacaine. For lumbar epidural anaesthesia for lower limb or genitourinary surgery, comparative data suggest that higher concentrations of ropivacaine (0.75 or 1.0%) may be needed to provide the same sensory and motor blockade as bupivacaine 0.5 and 0.75%. In patients about to undergo upper limb surgery, 30 to 40ml ropivacaine 0.5% produced brachial plexus anaesthesia broadly similar to that achieved with equivalent volumes of bupivacaine 0.5%, although the time to onset of sensory block tended to be faster and the duration of motor block shorter with ropivacaine. Ropivacaine had an adverse event profile similar to that of bupivacaine in clinical trials. Several cases of CNS toxicity have been reported after inadvertent intravascular administration of ropivacaine, but only 1 case of cardiovascular toxicity has been reported to date. The outcome of these inadvertent intravascular administrations was favourable.

CONCLUSION

Ropivacaine is a well tolerated regional anaesthetic with an efficacy broadly similar to that of bupivacaine. However, it may be a preferred option because of its reduced CNS and cardiotoxic potential and its lower propensity for motor block.

Comparison of ropivacaine 0.1% and 0.2% with bupivacaine 0.2% for single-shot caudal anaesthesia in children

We compared analgesic efficacy and degree of motor block induced by ropivacaine 0.1% (R 0.1) and 0.2% (R 0.2) vs. bupivacaine 0.2% (B 0. 2) after caudal anaesthesia in children. Total and free plasma concentrations were measured after caudal injection. Duration of caudal analgesia (median/range) was significantly shorter in group R 0.1 (1.7 h/0.2-6 h) than in group R 0.2 (4.5 h/1.7-6 h) or group B 0. 2 (4 h/1-6 h) (P<0.05). Motor block in the first 2 h postoperatively was significantly less for both ropivacaine groups compared with bupivacaine (P<0.05). Peak plasma concentrations after ropivacaine 0.2% were higher and protein binding lower than after bupivacaine 0.2% (P<0.05). We conclude that caudal analgesia with ropivacaine 0.1% is less effective and of shorter duration than that of ropivacaine 0.2%, whereas ropivacaine 0.2% provides pain relief similar to bupivacaine 0.2%. Motor block in the early postoperative period is less with ropivacaine than with bupivacaine.

What concentration of sufentanil should be combined with ropivacaine 0.2% wt/vol for postoperative patient-controlled epidural analgesia?

In this randomized double-blinded study, we sought to determine an optimal dose-combination of sufentanil with ropivacaine 0.2% wt/vol as postoperative epidural analgesics. One hundred twenty patients undergoing major abdominal surgery under general and thoracic epidural anesthesia (T9-11) were assigned to groups receiving patient-controlled epidural analgesia with ropivacaine 0.2% wt/vol (R), ropivacaine 0.2% wt/vol + sufentanil 0.5 microg/mL (R+S0.5), 0. 75 microg/mL (R+S0.75), 1.0 microg/mL (R+S1). A visual analog score of less than 40 was considered effective, and all side effects were recorded. In randomized subgroups (10 patients per group), plasma pharmacokinetic data were obtained for both epidural drugs. Four patients in Group R and two in Group R+S0.5 were excluded because of inadequate analgesia. The drug infusion rates (range of means: 5.4-5. 9 mL/h) were similar in all patients. Analgesia was superior for sufentanil 0.75 microg/mL with no further enhancement by the larger sufentanil concentration of 1 microg/mL. Sufentanil plasma levels were within the range of the minimal effective concentrations (highest in R+S1), and there was no covariation between plasma levels and pain relief. Free ropivacaine plasma concentrations remained stable for 96 h. No severe side effects were detected, although pruritus correlated with an increasing dose of sufentanil. We conclude that the combination of ropivacaine 0.2% wt/vol and 0.75 microg/mL sufentanil provided the best analgesia with the fewest side effects of the three combinations tested.

IMPLICATIONS

Sufentanil is added to epidural infusions of ropivacaine 0.2% wt/vol to improve the effectiveness of postoperative pain management. Regarding the risk of side effects, however, it is still unclear what concentration of sufentanil should be added to the local anesthetic. For postoperative thoracic epidural analgesia after major abdominal surgery, the combination of ropivacaine 0.2% wt/vol and 0.75 microg/mL sufentanil resulted in an appropriate cost:benefit ratio between good analgesia and side effects.

Ropivacaine epidural anesthesia and analgesia versus general anesthesia and intravenous patient-controlled analgesia with morphine in the perioperative management of hip replacement. Ropivacaine Hip Replacement Multicenter Study Group

The aim of our study was to compare epidural anesthesia and analgesia (EDA) with ropivacaine versus general anesthesia followed by IV patient-controlled analgesia with morphine (GA/PCA) after hip replacement regarding pain, side effects, and discharge from the postanesthesia care unit. After ethics committee approval, randomization, and informed consent, 90 patients were enrolled. In Group EDA, epidural anesthesia (ropivacaine 10 mg/mL, 15-25 mL) was followed by an epidural infusion (2 mg/mL, 4-6 mL/h for 24 h, plus top-up doses of 6-10 mL for 48 h). GA/PCA patients received general anesthesia (isoflurane/N2O/fentanyl) followed by IV patient-controlled analgesia with morphine postoperatively. Pain was assessed by using visual analog scales (0-100 mm) at rest and during physiotherapy. Pain at rest was less in the EDA (n = 43) group than in the GA/PCA (n = 45) group (at 10 h: 11.8+/-12.9 vs. 28.4+/-17.1 [P< 0.001]; at 24 h: 14.3+/-11.7 vs. 24.0+/-17 [P<0.01]; in 48 h: 14.3+/-9.3 vs. 21.1+/-17.4 [P = 0.1]). Whereas EDA patients were deemed ready for discharge from the postanesthesia care unit earlier than GA/PCA patients (5.6+/-8.9 vs. 39.7+/-41.5 min), the actual discharge time was comparable. The median time for first passage of flatus was shorter in the EDA group than in the GA/PCA group (26 vs. 47 h). Nausea and vomiting were more common in the GA/PCA group than in the EDA group (16% vs. 28% and 11% vs. 22%, respectively), whereas hypotension (11% vs. 4%) and bradycardia (14% vs. 2%) were less frequent. Under the conditions of the present study, EDA with ropivacaine provided pain control after hip replacement superior to that provided by IV patient-controlled analgesia with morphine, particularly during the first 24 h. Both approaches to pain management were equally safe.

IMPLICATIONS

Compared with general anesthesia and postoperative IV patient-controlled analgesia with morphine, epidural anesthesia and analgesia with the new local anesthetic ropivacaine enables patients to be discharged sooner from a postanesthesia care unit and provides superior pain relief during the first 24 h after hip replacement.

Surgical-site complications associated with a morphine nerve paste used for postoperative pain control after laminectomy

OBJECTIVE

To identify risk factors that might explain a sudden increase in the rate of surgical-site complications following laminectomy.

DESIGN

Retrospective cohort study.

PATIENTS AND SETTING

Patients who underwent laminectomy at a 120-bed hospital from August 1 through October 15, 1996 (the epidemic period). A case-patient was defined as a patient with postoperative surgical-site complications (surgical-site drainage, edema, or swelling) requiring surgical debridement.

RESULTS

Of the 148 patients who underwent a laminectomy during the epidemic period, 17 (11%) met our case definition. The rate of postoperative surgical debridement was 7.6-fold higher during the epidemic period than the preceding 19-month period (17/148 vs 15/995, P<.001). Development of surgical-site complications was associated with intraoperative receipt of morphine nerve paste (relative risk [RR], 11; P<.001), preoperative shaving by nurses rather than surgeons (RR, 6.6; P=.006), procedures done by a certain surgeon (RR, 3.1; P=.022), or receipt of iodine rather than povidone-iodine for preoperative skin antisepsis (RR, 5.1; P=.002). In multivariate analysis, only receipt of morphine nerve paste remained as a risk factor (RR, 18; P=.011). The paste was used to control postoperative pain and was applied directly to exposed dura and surrounding tissues. At the time of surgical debridement (median, 24 days postsurgery), the original surgical sites showed residual paste and a lack of healing. Ten of 16 cultures from surgical sites were positive; all but three grew skin commensals. Histological examination of surgical specimens showed a foreign-body reaction, but no marked acute inflammation.

CONCLUSIONS

The intraoperative use of morphine nerve paste may delay wound healing and increase postoperative morbidity. When new products are introduced, standardized protocols should be developed for their use, and systematic surveillance should be done to monitor for potential adverse outcomes.