Double-blind comparison of ropivacaine 7.5 mg ml(-1) with bupivacaine 5 mg ml(-1) for sciatic nerve block

Two groups of 12 patients had a sciatic nerve block performedwith 20 ml of either ropivacaine 7.5 mg ml^–1 or bupivacaine5 mg ml^–1. There was no statistically significant differencein the mean time to onset of complete anaesthesia of the footor to first request for post-operative analgesia. The qualityof the block was the same in each group. Although there wasno statistically significant difference in the mean time topeak plasma concentrations the mean peak concentration of ropivacainewas significantly higher than that of bupivacaine. There wereno signs of systemic local anaesthetic toxicity in any patientin either group. Br J Anaesth 2001; 86: 674–7     

Comparison of ropivacaine 2 mg ml(-1) and prilocaine 5 mg ml(-1) for i.v. regional anaesthesia in outpatient surgery

Background. Ropivacaine 2 mg ml^–1 (0.2%) provides longer-lastinganalgesia after deflation of the tourniquet cuff, with fewerside-effects, than lidocaine 5 mg ml^–1 (0.5%) after i.v.regional anaesthesia (IVRA). Whether ropivacaine 2 mg ml^–1also exerts this advantage over prilocaine 5 mg ml^–1,the local anaesthetic of choice in IVRA in most European countrieswas investigated in this study. Methods. Sixty outpatients scheduled for forearm or hand surgeryreceived IVRA with 40 ml of ropivacaine 2 mg ml^–1 (Ropi)or prilocaine 5 mg ml^–1 (Prilo) in a randomized, double-blindedfashion. The development and recovery of pin-prick analgesiaand motor power of the hand, as well as ropivacaine and prilocaineplasma concentrations (n=30), were assessed during and afteroperation. Results. Anaesthesia for surgery was adequate in both groups.Pin-prick analgesia was achieved at a similar rate, except inthe radial nerve distribution area where at 10 min 60% of Ropiand 90% of Prilo patients had analgesia (P=0.017). At 10 min100 and 97% had motor block of the hand in the Ropi and Prilogroups, respectively. Recovery of the sensory block in all innervationareas was already observed 2 min after the tourniquet cuff release.At 10 min after releasing the tourniquet cuff 31% of the Ropipatients and none of the Prilo patients still had analgesiain the median nerve distribution (P=0.004). At 12 min, 42% inthe Ropi group and none in the Prilo group had decreased gripstrength. After the release of the tourniquet, mean plasma concentrationsof ropivacaine were higher than those of prilocaine. The highestindividual concentration of ropivacaine was 1.65 µg ml^–1and that of prilocaine 0.6 µg ml^–1. None of theRopi patients experienced any symptoms of local anaesthetictoxicity. Conclusions. Compared with prilocaine 5 mg ml^–1, analgesiain IVRA with ropivacaine 2 mg ml^–1 developed slightlymore slowly, while motor block developed at a similar rate.After the release of the tourniquet, sensation recovered quicklyand at a similar rate in the two groups, except for a slightlyslower recovery after ropivacaine in the innervation area ofthe median nerve, but no surgically useful extended analgesiaafter the cuff deflation was observed. Despite a 60% lower milligram-dose,ropivacaine plasma concentrations were markedly higher thanthose of prilocaine.     

Spinal anaesthesia for Caesarean section with bupivacaine 5 mg ml(-1) in glucose 8 or 80 mg ml(-1)

The standard spinal preparation of bupivacaine contains a highconcentration of glucose (80 mg ml^–1). However,the addition of only a small amount of glucose (8 mg ml^–1)to plain solutions of bupivacaine results in a solution which,although no more than marginally hyperbaric, produces a morepredictable block when used for spinal anaesthesia in non-pregnantpatients. However, bupivacaine 5 mg ml^–1 inglucose 8 mg ml^–1 has a density [1.00164 (SD0.00008) at 37°C] which is relatively greater than thatof the cerebrospinal fluid (CSF) of the pregnant patient atterm (1.0003 at 37°C) because CSF density decreases duringpregnancy. Therefore, a double-blind, randomized, controlledstudy was carried out to compare intrathecal bupivacaine (glucose8 mg ml^–1) with bupivacaine (glucose 80 mg ml^–1)in 40 pregnant patients at term. Although there was no differencebetween groups in onset of sensory block, dose of ephedrineor patient satisfaction, patients receiving bupivacaine (5 mg ml^–1)with glucose (8 mg ml^–1) had persistently highersensory blocks between 60 and 120 min after intrathecalinjection, suggesting that the spread of spinal solutions inthe pregnant patient at term is not dependent on density. Br J Anaesth 2001; 86: 805–7     

Intrathecal ropivacaine or bupivacaine with fentanyl for labour

Combined spinal-epidural (CSE) is widely used to provide painrelief in labour while minimizing motor blockade. Aiming tofurther reduce associated motor weakness, we compared ropivacaine2.5 mg in the intrathecal injection with a standard bupivacaineCSE in a double-blind study. Forty women were randomized toreceive either bupivacaine 2.5 mg or ropivacaine 2.5 mg intrathecally,both with fentanyl 0.025 mg. There were no significant differencesbetween the groups regarding the onset, duration or qualityof analgesia or the level of sensory block attained. Forty percent of the women (8/20) receiving bupivacaine developed detectablemotor block compared with only 5% (1/20) in the ropivacainegroup (P<0.05). Vibration sense was impaired in one womanin each group. Adverse effects did not differ between groups.We conclude that intrathecal ropivacaine 2.5 mg in combinationwith fentanyl 0.025 mg as part of a CSE technique provides rapidand safe analgesia for labour as effective as that achievedwith bupivacaine 2.5 mg and with significantly less motor block. Br J Anaesth 2001; 87: 733–7     

Comparison of hyperbaric and plain ropivacaine 15 mg in spinal anaesthesia for lower limb surgery

Background. Previously, plain ropivacaine 15 mg given intrathecallyhas been shown to be feasible for ambulatory surgery of lower-extremities.Hypothetically, hyperbaric solution could improve and shortenthe block. Methods. This prospective, randomized, double-blind study included56 patients undergoing surgery of lower extremities. They receivedintrathecally either 1.5 ml of ropivacaine 10 mg ml^–1and 0.5 ml of glucose 300 mg ml^–1 (HYP) or 2 ml of ropivacaine7.5 mg ml^–1 (PL). Results. All patients in Group HYP achieved T₁₀ dermatome analgesiabut only 64% (18/28) of Group PL. T₁₀ analgesia was reachedin 5 min (median, range 5–20 min) in the HYP group vs10 min (5–45 min) in the PL group (P=0.022), and fullmotor block in 10 min (5–45 min) vs 20 min (5–60min) (P=0.003), respectively. Group HYP had a longer durationof analgesia at T₁₀; 83 min (5–145 min) vs 33 min (0–140min) (P=0.004). Duration of sensory block from injection ofthe anesthetic to complete recovery was shorter in Group HYPthan in Group PL, 210 min (120–270 min) vs 270 min (210–360min) (P<0.001), as was duration of motor block, 120 min (5–150min) vs 210 min (120–330 min) (P<0.001). Patients ofGroup HYP attained discharge criteria earlier than those ofGroup PL (P=0.009). Conclusion. In comparison with the plain solution, 15 mg ofintrathecal hyperbaric ropivacaine produced a faster onset,greater success rate of analgesia at the level of T₁₀ dermatome,and faster recovery of the block.     

Epidural ropivacaine 7.5 mg/ml for elective Caesarean section: A double-blind comparison of efficacy and tolerability with bupivacaine 5 mg/ml

BACKGROUND: Ropivacaine is a new local anaesthetic drug known to be less cardiotoxic than bupivacaine. The aims of this comparative study with bupivacaine were to evaluate efficacy, safety and tolerability for the mother and the neonate when using ropivacaine 7.5 mg/ml for epidural anaesthesia for elective Caesarean section. METHODS: In a double-blind, multicentre trial the patients were randomised to receive 20 ml of either ropivacaine 7.5 mg/ml or bupivacaine 5 mg/ml. The quality of the peroperative analgesia and abdominal muscle relaxation as well as tolerability and safety in both the mother and the neonate were evaluated. RESULTS: A total of 122 patients were evaluated for efficacy and tolerability. There were no significant differences in the onset time and the extent of the sensory spread or motor block. The peroperative quality of anaesthesia and muscle relaxation was similar in both groups. No significant side effects were observed, except for a more profound drop in systolic blood pressure in the ropivacaine group. The anaesthetics were well tolerated by the neonate in both groups, evaluated by Apgar and NACS scores. CONCLUSION: Ropivacaine 7.5 mg/ml administered epidurally resulted in equally effective anaesthesia for Caesarean section as bupivacaine 5 mg/ml. Because of the lower cardiotoxicity of ropivacaine, the new amide has a potential in replacing bupivacaine when used epidurally for Caesarean section.     

Axillary brachial plexus block with ropivacaine 7.5 mg/ml

BACKGROUND: Ropivacaine is less cardiotoxic than bupivacaine and may be used in higher doses in order to increase the quality of a block. The aim of this study was to compare the efficacy and safety of 40 ml ropivacaine 7.5 mg/ml (300 mg) and 40 ml bupivacaine 5 mg/ml (200 mg) for axillary plexus block. METHODS: One hundred and four adult patients were included in a prospective, double-blind study. Sensory and motor block were tested for the five main terminal nerves of the arm at 10-min intervals until start of surgery and every second hour there-after until full resolution of the block. RESULTS: The overall evaluation of the block by the surgeon and the anesthesiologist showed a significantly better quality in the ropivacaine patients, regarding both anesthesia and motor block. There were no differences in the time to onset and duration of the block. Except for one patient, who had seizures after an accidental IV injection of ropivacaine, there were no major side effects. CONCLUSION: Ropivacaine 7.5 mg/ml, 40 ml, produces axillary plexus block of similar onset and duration but better quality than 40 ml of bupivacaine 5.0 mg/ml.     

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.     

Comparison of ropivacaine 0.5% (in glucose 5%) with bupivacaine 0.5% (in glucose 8%) for spinal anaesthesia for elective surgery

Background. Hyperbaric solutions of ropivacaine have been usedsuccessfully to provide spinal anaesthesia. This study was designedto compare the clinical efficacy of hyperbaric ropivacaine withthat of the commercially available hyperbaric preparation ofbupivacaine. Methods. Forty ASA grade I–II patients undergoing lower-abdominal,perineal or lower-limb surgery under spinal anaesthesia wererecruited and randomized to receive ropivacaine 5 mg ml^–1(with glucose 50 mg ml^–1), 3 ml or bupivacaine 5 mg ml^–1(with glucose 80 mg ml^–1), 3 ml. The level and durationof sensory block, intensity and duration of motor block, andtime to mobilize and micturate were recorded. Patients wereinterviewed at 24 h and at 1 week to identify any residual problems. Results. All blocks were adequate for the proposed surgery,but there were significant differences between the two groupsin mean time to onset of sensory block at T10 (ropivacaine 5min; bupivacaine 2 min; P<0.005), median maximum extent (ropivacaineT7; bupivacaine T5; P<0.005) and mean duration of sensoryblock at T10 (ropivacaine 56.5 min; bupivacaine 118 min; P=0.001).Patients receiving ropivacaine mobilized sooner (ropivacainemean 253.5 min; bupivacaine 331 min; P=0.002) and passed urinesooner (ropivacaine mean 276 min; bupivacaine 340.5 min; P=0.01)than those receiving bupivacaine. More patients in the bupivacainegroup required treatment for hypotension (>30% decrease insystolic pressure; P=0.001). Conclusions. Ropivacaine 15 mg in glucose 50 mg ml^–1 providesreliable spinal anaesthesia of shorter duration and with lesshypotension than bupivacaine. The recovery profile for ropivacainemay be of interest given that more surgery is being performedin the day-case setting. Br J Anaesth 2003; 90: 304–8     

Premixed solutions of diamorphine in ropivacaine for epidural anaesthesia: a study on their long-term stability

Background. Local anaesthetics and opioid mixtures are commonlyused to provide anaesthesia or analgesia during the perioperativeperiod. In order to facilitate their preparation and storageit is necessary to establish the stability of such solutions. Methods. In our study, diamorphine was added to ropivacaine0.2% 200-ml polybags to give a concentration of 25 µg ml^–1and to ropivacaine 1% 50-ml syringes to give a concentrationof 45 µg ml^–1. The polybags and syringeswere stored at 40°C, 21°C and 4°C for up to 120days. Samples were taken during this period for measurementof diamorphine and ropivacaine content and pH of the solutions. Results. We found that the storage temperature and the initialconcentration influenced the rate of degradation of diamorphinein both the polybags and the syringes. In the syringes, 10%degradation of diamorphine [T (0.9)] was: 6 days at 40°C,16 days at 21°C and 30 days at 4°C. In the polybags,diamorphine T (0.9) was 6 days at 40°C, 28 days at 21°Cand 70 days at 4°C. Conclusions. It is feasible to manufacture such solutions inpharmacy aseptic units and to store them for up to 1 month forroutine use in epidural infusions. Br J Anaesth 2003; 90: 179–82     

Density of spinal anaesthetic solutions of bupivacaine, levobupivacaine, and ropivacaine with and without dextrose

Background. Spread of intrathecal local anaesthetics is determinedprincipally by baricity and position of the patient. Hypobaricsolutions of bupivacaine are characterized by an unpredictablespread of sensory block whereas addition of dextrose 80 mg ml^–1provides a predictable spread but to high thoracic levels. Incontrast, dextrose concentrations between 8 and 30 mg ml^–1have shown reliable and consistent spread for surgery. Hence,the aim of this study was to determine the density of bupivacaine,levobupivacaine, and ropivacaine with and without dextrose atboth 23 and 37°C before embarking on clinical studies. Methods. Density (mg ml^–1) was measured using the methodof mechanical oscillation resonance, accurate to five decimalplaces on 1250 samples. 500 density measurements were performedin a randomized, blind fashion at 23 and 37°C on 10 plainsolutions of bupivacaine (2.5, 5, and 7.5 mg ml^–1) levobupivacaine(2.5, 5, and 7.5 mg ml^–1) and ropivacaine (2, 5, 7.5,and 10 mg ml^–1). Following this, 750 density measurementswere taken at 23 and 37°C on the 5 mg ml^–1 solutionsof bupivacaine, levobupivacaine, and ropivacaine with addeddextrose (10, 20, 30, 50, and 80 mg ml^–1). Results. There was a linear relationship between density anddextrose concentration for all three local anaesthetics (R²=0.99)at 23 and 37°C. The mean density of levobupivacaine 5 mgml^–1 was significantly greater than the densities of bupivacaine5 mg ml^–1 and ropivacaine 5 mg ml^–1 after adjustingfor dextrose concentration using analysis of covariance. Thisdifference existed both at 23 and 37°C. The mean (SD) densityof levobupivacaine 7.5 mg ml^–1 was 1.00056 (0.00003) mgml^–1, the lower 0.5% percentile (1.00047 mg ml^–1)lying above the upper limit of hypobaricity for all patientgroups. Conclusions. The density of local anaesthetics decreases withincreasing temperature and increases in a linear fashion withthe addition of dextrose. Levobupivacaine 5 mg ml^–1 hasa significantly higher density compared with bupivacaine 5 mgml^–1 and ropivacaine 5 mg ml^–1 at 23 and 37°Cboth with and without dextrose. Levobupivacaine 7.5 mg ml^–1is an isobaric solution within all patient groups at 37°C. Br J Anaesth 2004; 92: 547–51     

Spinal anaesthesia with articaine 5% vs bupivacaine 0.5% for day-case lower limb surgery: a double-blind randomized clinical trial

BACKGROUND: A local anaesthetic with fast onset and short reliable duration of anaesthesia may be preferable for out-patient lower limb surgery. Articaine is believed to act faster and to have a shorter duration of action than bupivacaine, but there are no conclusive data available. The purpose of this study was to compare articaine and bupivacaine for day-case lower limb surgery. METHODS: Eighty patients planned for day-case lower limb surgery enrolled in this study. Patients were randomized to receive hyperbaric articaine 80 mg or plain bupivacaine 15 mg intrathecally. Primary outcome variable was recovery time from motor block. Secondary outcomes were: onset of sensory and motor block, maximum spread of sensory block, time to micturition, discharge from the hospital, and complications. RESULTS: The groups were comparable for the medians and the range of the maximum blocks after 30 min. Median time to complete regression of motor block was 101 min (range 80-129) for articaine compared with 307 min (range 225-350) for bupivacaine (P<0.0005). First spontaneous micturition occurred after 257 min (210-293) in the articaine group and after 350 min (304-370) in the bupivacaine group (P<0.0005). In the articaine and bupivacaine groups, patients were discharged after 300 min (273-347) and 380 min (332-431), respectively (P<0.0005). There was no significant difference in the occurrence of complications between the groups. CONCLUSIONS: Spinal anaesthesia with 80 mg of hyperbaric articaine has a shorter duration than a spinal anaesthesia with 15 mg of plain bupivacaine in lower limb surgery of approximately 1 h duration.     

Small dose of clonidine mixed with low-dose ropivacaine and fentanyl for epidural analgesia after total knee arthroplasty

Background. We studied whether a small dose of clonidine addedto a ropivacaine–fentanyl mixture improves epidural analgesiawithout provoking side effects typically related to larger amountsof epidural clonidine. Methods. In this randomized, double-blinded study, patients(     

Efficacy and uptake of ropivacaine and bupivacaine after single intra-articular injection in the knee joint

The efficacy of ropivacaine 100 mg (5 mg ml^–1),150 mg (7.5 mg ml^–1) and 200 mg (10 mg ml^–1)and bupivacaine 100 mg (5 mg ml^–1) givenby intra-articular injection into the knee after the end ofsurgery was studied in 72 ASA I–II patients scheduledfor elective knee arthroscopy under general anaesthesia in arandomized, double-blind study. Kapake (paracetamol 1 gand codeine 60 mg) was given as a supplementary analgesic.Pain scores were assessed 1–4 h after surgery and a verbalrating scale of overall pain severity was assessed on secondpostoperative day. Ropivacaine or bupivacaine concentrationswere determined in peripheral venous plasma up to 3 h afterinjection in eight patients in each group. Verbal rating painscores were lower with ropivacaine 150 mg compared withbupivacaine 100 mg (P<0.05). There was a tendency forlower analgesic consumption and pain scores with all doses ofropivacaine (not significant). The mean (SD) maximum total plasmaconcentrations of ropivacaine were 0.64 (0.25), 0.78 (0.43),and 1.29 (0.46) mg litre^–1 after 100, 150 and200 mg. The corresponding unbound concentrations were 0.018(0.009), 0.024 (0.020) and 0.047 (0.022) mg litre^–1.Both were proportional to the dose. The maximum total concentrationafter bupivacaine 100 mg was 0.57 (0.36) mg litre^–1.The time to reach maximum plasma concentration was similar forall doses and varied between 20 and 180 min. All concentrationswere well below the threshold for systemic toxicity. Br J Anaesth 2001; 87: 570–6     

A prospective, double-blind, randomized trial of caudal block using ropivacaine 0.2% with or without fentanyl 1 microg kg-1 in children

Background. It has been reported that ropivacaine produces vasoconstrictionin contrast to vasodilation produced by bupivacaine. It is possiblethat additives to ropivacaine can provide further analgesicadvantages compared with bupivacaine. We thus evaluated whetherthe addition of fentanyl to ropivacaine prolonged the durationof analgesia after a single shot caudal block. Methods. A total of 36 children undergoing surgical proceduresbelow the umbilicus were randomly allocated to one of two groups:Group F received ropivacaine 0.2%, 1 ml kg^–1 with fentanyl1 µg kg^–1 and Group S received ropivacaine 0.2%,1 ml kg^–1 with saline. The analgesic effect of the caudalblock was evaluated using the Children's Hospital of EasternOntario Pain Scale (CHEOPS) and sedation was assessed usingthe Steward score at 30 min after extubation and at 1, 2, 4,6, 12 and 24 h. The first analgesic requirement time and side-effectsin a 24 h period were also recorded. Results. There were no differences in characteristics betweenthe groups. The end-tidal concentration of sevoflurane at extubationin Group F was significantly lower than in Group S. However,there was no significant difference in time from discontinuationof the volatile anaesthetics to tracheal extubation. No statisticaldifferences were found in the CHEOPS and Steward score, andthe time to first analgesia. The incidence of postoperativevomiting was not significantly different. Conclusion. We found that the addition of fentanyl 1 µgkg^–1 to ropivacaine 0.2% for caudal analgesia providesno further analgesic advantages over ropivacaine 0.2% alone.     

Comparison of intrathecal isobaric bupivacaine-morphine and ropivacaine-morphine for Caesarean delivery

Background. This study was designed to evaluate the effectsof intrathecal isobaric bupivacaine 0.5% plus morphine and isobaricropivacaine 0.5% plus morphine combinations in women undergoingCaesarean deliveries. Method. Twenty-five parturients received ropivacaine 15 mg andmorphine 150 µg (RM group) and twenty-five parturientsreceived bupivacaine 15 mg and morphine 150 µg (BM group)for spinal anaesthesia. Sensory and motor block, haemodynamics,postoperative analgesia, fetal outcomes, and side-effects wereevaluated. Results. Intrathecal bupivacaine–morphine and ropivacaine–morphineprovided effective sensory anaesthesia and motor block. Timeto reach complete motor block was shorter and time to completerecovery from motor block was longer in the BM group than theRM group (P<0.05). The time to regression of two dermatomesand time for the block to recede to the S2 dermatome were similarin both groups (P>0.05). Time to first complaint of painand the mean total consumption of tenoxicam were similar inboth groups (P>0.05). APGAR scores at 1 and 5 min were similarin the two groups, as were mean umbilical blood pH values (P>0.05).Hypotension and pruritus were the most common side-effects inboth groups during the operation. Conclusion. Intrathecal isobaric ropivacaine 0.5% 15 mg plusmorphine 150 µg provides sufficient anaesthesia for Caesareandelivery. The ropivacaine–morphine combination resultedin shorter motor block, similar sensory and postoperative analgesia. Br J Anaesth 2003; 90: 659–64     

全髋关节表面置换术与传统全髋关节置换术围手术期总失血量的比较研究

目的比较全髋表面置换术（HRA）和传统全髋置换术（THA）围手术期的总失血量以及术后住院时间,探讨两种术式不同的失血机制及其对手术创伤的影响。方法 2009年1月至2009年12月,选择67例髋关节骨病患者,分为两组分别施行HRA和THA,HRA组34例（34髋）,THA组33例（33髋）THA,两组均为初次单侧关节置换。通过Gross方程,根据身高、体重和手术前后的红细胞压积（Hct）变化差值算出所有患者的总失血量,记录显性失血量（术中出血和术后引流量）,推算出隐性失血量。记录手术时间和术后住院时间,将以上数据进行比较。结果 HRA组总失血量、显性失血量和隐性失血量都与THA组有统计学差异。总失血量HRA组和THA组分别为（1048.0±134.2）ml和（1466.0±167.4）ml,两组间差异有统计学意义（t=11.3,P〈0.05）;术中出血量分别为（542.0±68.9）ml和（625.0±86.3）ml,两组间差异有统计学意义（t=4.4,P〈0.05）;术后引流量分别为（266.0±93.9）ml和（379.0±162.7）ml,两组间差异有统计学意义（t=3.5,P〈0.05）;平均隐性失血量分别为（240.0±43.4）ml和（462.0±71.5）ml,两组间差异有统计学意义（t=15.3,P〈0.05）;平均术后住院时间HRA组也明显缩短,HRA为（4.6±0.9）d,THA为（6.1±0.9）d,两组间差异有统计学意义（t=7.0,P〈0.05）;平均手术时间HRA组则比HA组延长,HRA组为（114±13.9）min,THA组为（87±18.5）min,两组间差异有统计学意义（t=-6.9,P〈0.01）。结论尽管HRA比THA手术时间和手术切口都有延长,但总出血量明显降低,尤其是隐形失血量,术后住院时间也缩短,说明HRA出血相对偏少,创伤相对较小。     

Epidural test dose with levobupivacaine and ropivacaine: determination of ED(50) motor block after spinal administration

Background. When a test is required to detect a possible intrathecalcatheter, many would seek to use the same local anaestheticas that used for epidural analgesia. The rapid onset of inappropriatemotor block after a local anaesthetic administered epidurallyimplies intrathecal spread. Because of claims of greater sensory–motorseparation, or because of reduced potency compared with bupivacaine,the efficacy of the new local anaesthetics in intrathecal testinghas been questioned. The aim of this study was to establishthe feasibility of a test dose for an inadvertent intrathecalcatheter using ropivacaine and levobupivacaine, and to establishthe dose required. Methods. Sixty women undergoing elective Caesarean section witha combined spinal– epidural technique were enrolled intothis prospective, double-blind sequential allocation study.The women were randomized to receive plain levobupivacaine 0.5%or ropivacaine 0.5% intrathecally. The dose was determined accordingto up–down sequential allocation. The end-point was anyevidence of lower limb motor block within 5 min of injection. Results. The ED₅₀ motor block at 5 min was 4.8 mg (95% CI, 4.49,5.28) for levobupivacaine and 5.9 mg (95% CI, 4.82, 6.98) forropivacaine (95% CI difference, 0.052, 1.98) (P=0.04). The estimatedED₉₅ motor block was 5.9 mg (95% CI 5.19, 6.71) for levobupivacaineand 8.3 mg (95% CI, 6.30, 10.44) for ropivacaine. The potencyratio between the two drugs was 0.83 (95% CI, 0.69, 0.99). Conclusions. Both local anaesthetics produce evidence of motorblock within 5 min of intrathecal injection and could serveas tests of intrathecal administration. Derived ED₉₅ valuessuggest 10 mg doses should be effective, but this study didnot measure predictive value. Ropivacaine is less potent formotor block than levobupivacaine by a factor of 0.83 (P<0.04). Br J Anaesth 2004; 92: 850–3     

Continuous spinal microcatheter (28 gauge) technique for arterial bypass surgery of the lower extremities and comparison of ropivacaine with or without morphine for postoperative analgesia

Background. The aim of this study was to evaluate a microcathetertechnique for continuous spinal anaesthesia (CSA) and continuousspinal postoperative analgesia (CSPA) in vascular surgery. Methods. A total of 47 patients (range 51–95 yr, ASA II–IV)undergoing peripheral bypass surgery of the lower extremitiesreceived a spinal microcatheter (28 gauge) at L3–L4 orL2–L3. For CSA, ropivacaine 7.5 mg ml^–1 was givenin small increments. Central venous pressure was maintained3 mm Hg. Of 47 patients, 44 received CSPA, either using ropivacainealone 2 mg h^–1 (group R, n=22) or ropivacaine 1 mg h^–1with morphine 8 µg h^–1 (group RM, n=22) for 24 hafter surgery (randomized, double-blinded). Results. Intraoperative haemodynamic control was good; duringthe initial 60 min only four patients received phenylephrinei.v. for hypotension. Up to 30% of the patients felt mild painat incision but surgery [mean duration 173 min (range 66–327)]was successfully completed under CSA in 45 patients. In fourinstances of acute revision surgery, a new block was administeredutilizing the spinal catheter in place. Postoperative pain reliefwas comparably adequate in both groups with no difference inrescue pain medication. Four patients (three in R, one in RM)had weak motor blockade in the first postoperative morning. Conclusions. The described CSA technique offered good haemodynamiccontrol, ease of maintaining spinal anaesthesia, and ease ofproviding a new spinal block for revision. The combination oflow-dose ropivacaine and morphine for CSPA did not offer anybenefit compared with the higher ropivacaine dose alone. Presented in part at the 28th Congress of the Scandinavian Societyof Anaesthesiology and Intensive Care Medicine, Reykjavik, Iceland,June 29–July 3, 2005     

Intraocular pressure and ropivacaine in peribulbar block: a comparative study with bupivacaine

BACKGROUND: The aim of this study was to compare the effects on intraocular pressure (IOP) of ropivacaine and bupivacaine in peribulbar block. METHODS: The study involved 40 patients with ASA physical status I, II or III undergoing cataract surgery under peribulbar block. Patients were allocated to two groups according to the local anesthetic used: Group R (n=20), 1.0% ropivacaine and Group B (n=20) 0.75% bupivacaine, both associated with 50 IU. ml-1 hyaluronidase, in peribulbar double injection technique. IOP was measured at four time points: 0=before block (control); 1=1 min after block; 2=5 min after block; 3=15 min after block. RESULTS: Mean values of IOP (mm Hg) after block were significantly lower in Group R in comparison to Group B: time point 1=13.4+/-3.2 vs 20.8+/-4.7; time point 2=10.9+/-3.7 vs 14.4+/-3.8; time point 3=7.7+/-4.0 vs 10.5+/-3.1. The variation of IOP was different in each group. In Group R, the mean values obtained at the three time points after block were significantly lower than the control; in Group B, the mean value of IOP rose significantly 1 min after block and was lower than control only at time point 3. CONCLUSIONS: Ropivacaine 1.0% associated with hyaluronidase in peribulbar block is better than 0.75% bupivacaine under the same standard conditions for lowering IOP in intraocular surgery. This effect is probably due to relaxation of the extraocular muscles after the block with both anesthetics, and possibly to a smaller intraocular blood volume due to vasoconstriction in the case of ropivacaine.