Pseudoendogenous origin of prednisolone in pigs from the food chain.

The debate about the origin of prednisolone in animal organisms has lasted for 5 years. Bovine species have been the most studied, but studies on humans and horses are also present in the literature. Even if prednisolone in pigs does not yet represent a problem for control agencies, interest has recently increased with regard to this species. To date, there has been just a single study in the literature about this topic, performed on 10 sows treated with prednisolone or a synthetic analogue of adrenocorticotropic hormone. We therefore initiated a study on 80 pigs, a number considered representative in relation to the expected frequency (prevalence) of prednisolone detection in urine collected at slaughter. Prednisolone was detected in urine both at the farm and at the slaughterhouse, with a concentration and frequency higher at slaughter. The presence of prednisolone was also studied in the adrenal glands, where the corticosteroids are produced in response to stress, and it was detected in 89% of the samples. These results, together with the similar behaviours of prednisolone and cortisol, i.e. a mutual rise in the two corticosteroids in urine collected at the slaughterhouse and the correlation between the concentrations of the two corticosteroids in the adrenal glands, seem to indicate an endogenous origin of prednisolone in pigs.

Prednisolone and prednisone neo-formation in bovine urine after sampling.

The rise in the frequency of detecting prednisolone in bovine urine from northern Italy has come into focus of attention in recent years. The possibility that neo-formation of prednisolone or that prednisone may occur in urine after collection of samples was therefore investigated. Cow urine collected for official routine controls in Lombardy containing more than 80 ng/ml cortisol, and prednisolone and prednisone below the decision limit (CCα) of the method (0.4 and 0.5 ng/ml, respectively) was used. The C1-2 dehydrogenation of naturally present cortisol and cortisone was checked by incubating urine, both contaminated and uncontaminated with faeces, at 37°C and by collecting samples at 0, 1, 2, 4, 6 and 24 h. The influence of Helix pomatia juice was also investigated in order to determine whether deconjugation could influence the reliability of the results. All samples were analysed by HPLC-MS3 for the presence of cortisol, cortisone, prednisolone and prednisone in negative electrospray ionisation mode, utilising the consecutive reaction monitoring of product ions derived from the formate molecular adduct ([M+HCOO]-). The observed neo-formation of prednisolone shows that inappropriate temperatures in sample storage and processing can result in an incorrect accusation of non-compliance. The faecal contamination of urine, performed with the aim to mimic a collection conducted without the necessary care, moreover, evoked a high increase in prednisolone concentration in two out of seven animals. Moreover, H. pomatia juice had no significant effect on the prednisolone concentration, indicating that this corticosteroid is present in its free form in cow urine.

Investigation of the origin of prednisolone in cow urine.

After a two-year period of the frequent detection of prednisolone-positive bovine urine samples in the Italian region of Lombardy, studies were initiated to investigate the source. Because the majority of positive samples were detected at the slaughterhouse, researchers hypothesised that, together with increased cortisol and cortisone, a small quantity of prednisolone could be produced by the cows in stressful situations. In the present study, three dairy cows underwent intramuscular treatments with tetracosactide hexaacetate, a synthetic analogue of adrenocorticotropic hormone, to simulate stress. The animals were slaughtered at the end of the study. The results indicated that prednisolone could be detected occasionally in the non-stressful state, but was consistently found in the urine of stressed cows (concentrations ranged from 1.01 to 4.08 ng/mL). To confirm the stress condition, urinary cortisol and cortisone were also detected at high concentrations in the urine, typically at concentrations of hundreds of nanograms per millilitre. The results of this preliminary study did not reveal the metabolic pathway responsible for prednisolone but suggested that this corticosteroid could be produced endogenously.

Cell-autonomous regulation of hematopoietic stem cell cycling activity by ATP.

Extracellular nucleotides regulate many cellular functions through activation of purinergic receptors in the plasma membrane. Here, we show that in hematopoietic stem cell (HSC), ATP is stored in vesicles and released in a calcium-sensitive manner. HSC expresses ATP responsive P2X receptors and in vitro pharmacological P2X antagonism restrained hematopoietic progenitors proliferation, but not myeloid differentiation. In mice suffering from chronic inflammation, HSCs were significantly expanded and their cycling activity was sensitive to treatment with the P2X antagonist periodate-oxidized 2,3-dialdehyde ATP. Our results indicate that ATP acts as an autocrine stimulus in regulating HSCs pool size.

Postoperative pain treatment SIAARTI Recommendations 2010. Short version.

The aim of these recommendations is the revision of data published in 2002 in the "SIAARTI Recommendations for acute postoperative pain treatment". In this version, the SIAARTI Study Group for acute and chronic pain decided to grade evidence based on the "modified Delphi" method with 5 levels of recommendation strength. Analgesia is a fundamental right of the patient. The appropriate management of postoperative pain (POP) is known to significantly reduce perioperative morbidity, including the incidence of postoperative complications, hospital stay and costs, especially in high-risk patients (ASA III-V), those undergoing major surgery and those hospitalized in a critical unit (Level A). Therefore, the treatment of POP represents a high-priority institutional objective, as well as an integral part of the treatment plan for "perioperative disease", which includes analgesia, early mobilization, early enteral nutrition and active physiokinesitherapy (Level A). In order to improve an ACUTE PAIN SERVICE organization, we recommend: --a plan for pain management that includes adequate preoperative evaluation, pain measurement, organization of existing resources, identification and training of involved personnel in order to assure multimodal analgesia, early mobilization, early enteral nutrition and active physiokinesitherapy (Level A); --the implementation of an Acute Pain Service, a multidisciplinary structure which includes an anesthetist (team coordinator), surgeons, nurses, physiotherapists and eventually other specialists; --referring to high-quality indicators in establishing an APS and considering the following key points in its organization (Level C): --service adoption; --identifying a referring anesthetist who is on call 24 hours a day; --patient care during the night and weekend; --sharing, drafting and updating written therapeutic protocols; --continuous medical education; --systematic pain assessment; --data collection regarding the efficacy and safety of the implemented protocols; --at least one audit per year. --a preoperative evaluation, including all the necessary information for the management of postoperative analgesia (Level C); --to adequately inform the patient about the risks and benefits of drugs and procedures used to obtain the maximum efficacy from the administered treatments (Level D). We describe pharmacological and loco-regional techniques with special attention to day surgery and difficult populations. Risk management pathways must be the reference for early identification and treatment of adverse events and chronic pain development.

Wave-number spectrum of drift-wave turbulence.

A simple model for the evolution of turbulence fluctuation spectra, which includes neighboring interactions leading to the usual dual cascade as well as disparate scale interactions corresponding to refraction by large scale structures, is derived. The model recovers the usual Kraichnan-Kolmogorov picture in the case of exclusively local interactions and midrange drive. On the other hand, when disparate scale interactions are dominant, a simple spectrum for the density fluctuations of the form |nk|2 proportional to k(-3)/(1+k2)2 is obtained. This simple prediction is then compared to, and found to be in fair agreement with, Tore Supra CO2 laser scattering data.

Turbulence in the TORE SUPRA tokamak: measurements and validation of nonlinear simulations.

Turbulence measurements in TORE SUPRA tokamak plasmas have been quantitatively compared to predictions by nonlinear gyrokinetic simulations. For the first time, numerical results simultaneously match within experimental uncertainty (a) the magnitude of effective heat diffusivity, (b) rms values of density fluctuations, and (c) wave-number spectra in both the directions perpendicular to the magnetic field. Moreover, the nonlinear simulations help to revise as an instrumental effect the apparent experimental evidence of strong turbulence anisotropy at spatial scales of the order of ion-sound Larmor radius.

Transcutaneous carbon dioxide monitoring in spontaneously breathing, nonintubated patients in the early postoperative period.

BACKGROUND: The authors investigated the accuracy of transcutaneous capnometry (TcPCO(2)) in estimating arterial blood carbon dioxide partial pressure (PaCO(2)) during spontaneous breathing in patients admitted to our surgical intensive care unit (ICU). METHODS: Serial TcPCO(2) and PaCO(2) measurements were taken in stable patients undergoing postoperative monitoring after major abdominal, vascular, or thoracic surgery. Patients were enrolled 12 hours after extubation. Exclusion criteria were pulmonary dysfunction, hemodynamic instability, or anemia. Linear regression, mixed models, and Bland-Altman analyses were used to compare accuracy and correlation between the two variables. Data are presented as means (95% confidence intervals). RESULTS: PaCO(2) values ranged between 26 mmHg and 52 mmHg. Mean values for TcPCO(2) and PaCO(2) were 35.3 (33.8-36.8) mmHg and 39.2 (37.6-40.7) (P<0.001). Bland-Altman analysis showed a bias of -3.8 (-5.1-2.5) mmHg with upper and lower limits of agreement of 5.6 (3.4-7.9) mmHg and -13.3 (-15.6 -11.1) mmHg, respectively. Thirty-one (55.4%) measurements disagreed by 3 mmHg or more. Linear mixed model analysis with adjustment for repeated measurements showed low correlation (r=0.63; P<0.0005). There were small but significant differences between patients in the correlation coefficient (P=0.04). CONCLUSION: TcPCO(2) showed moderate bias with wide limits of agreement when compared to PaCO(2) in our patients. The regression model showed low correlation of the measurements when adjusting for repeated measurements and between-subject variances. TcPCO(2) may not provide an accurate quantitative estimation of PaCO(2) in stable, spontaneously breathing, nonintubated patients in the early postoperative period.

A prospective, randomized, double-blind comparison between parecoxib and ketorolac for early postoperative analgesia following nasal surgery.

BACKGROUND: The aim of this prospective, randomized, double-blind study was to compare the efficacy of parecoxibfor postoperative analgesia after endoscopic turbinate and sinus surgery, with the non-selective non-steroid anti-inflammatory drug (NSAID), ketorolac. METHODS: A total of 50 patients with an ASA physical status I-II, receiving functional endoscopic sinus surgery (FESS) and endoscopic turbinectomy after local infiltration with 1% mepivacaine, were randomly assigned to receive intravenous administration of either 40 mg parecoxib (N.=25) or 30 mg ketorolac (N.=25), 15 min before the discontinuation of anaesthesia and then every 8 h postoperatively. A blinded observer recorded the incidence and severity of pain upon admission to the postanesthesia care unit (PACU), as well as 10, 20, and 30 min after PACU admission. Thereafter, observations continued every 1 h for the first 6 h, and then 12 h and 24 h after surgery. RESULTS: The area under the curve of the visual analogue scale (AUCVAS) calculated during the study period was 635 (26-1 413) in the Parecoxib group and 669 (28-1 901) in the Ketorolac group (P=0.54). Rescue morphine analgesia was required by 12 patients (48%) in the Parecoxib group and 11 patients (44%) in the Ketorolac group (P<0.05); while mean morphine consumption was 5 +/- 2.5 mg and 5 +/- 2.0 mg in Ketorolac and Parecoxib groups, respectively (P<0.05). No differences in the incidence of side effects were recorded between the two groups. Patient satisfaction was similarly high in both groups, and all patients were discharged uneventfully 24 h after surgery. CONCLUSION: In patients undergoing endoscopic nasal surgery and local infiltration with 1% mepivacaine, parecoxib administered before discontinuing general anesthesia is as effective in treating early postoperative pain as ketorolac.

Effects of ultrasound guidance on the minimum effective anaesthetic volume required to block the femoral nerve.

BACKGROUND: We tested the hypothesis that ultrasound guidance may reduce the minimum effective anaesthetic volume (MEAV50) of ropivacaine 0.5% required to block the femoral nerve compared with nerve stimulation guidance. METHODS: After standard premedication and sciatic nerve block were given, 60 patients undergoing knee arthroscopy were randomly allocated to receive a femoral nerve block with ropivacaine 0.5% using either nerve stimulation (group NS, n = 30) or ultrasound (group US, n = 30) guidance. The volume of the injected solution was varied for consecutive patients based on an up-and-down staircase method according to the response of the previous patient. The initial volume was 12 ml. A double-blinded observer evaluated the occurrence of complete loss of pinprick sensation in the femoral nerve distribution, with concomitant block of the quadriceps muscle: positive or negative responses within 30 min after the injection determined a 3 ml decrease or increase for the next patient, respectively. RESULTS: The mean (sd) MEAV50 for femoral nerve block was 15 (4) ml (95% CI, 7-23 ml) in group US and 26 (4) ml (95% CI, 19-33 ml) in group NS (P = 0.002). The effective dose in 95% of cases (ED95) calculated with probit transformation and logistic regression analysis was 22 ml (95% CI, 13-36 ml) in group US, and 41 ml (95% CI, fs 24-66 ml) in group NS. CONCLUSIONS: Ultrasound guidance provided a 42% reduction in the MEAV of ropivacaine 0.5% required to block the femoral nerve as compared with the nerve stimulation guidance.

Ipsilateral shoulder pain after thoracotomy surgery: a prospective, randomized, double-blind, placebo-controlled evaluation of the efficacy of infiltrating the phrenic nerve with 0.2%wt/vol ropivacaine.

BACKGROUND: The aim of this prospective, randomized, double-blind, placebo-controlled study was to evaluate the efficacy of phrenic nerve infiltration with ropivacaine 0.2% on the incidence and severity of ipsilateral shoulder pain after thoracotomy in patients receiving continuous thoracic epidural analgesia. METHODS: Fifty ASA physical status II-III patients, receiving thoracic epidural analgesia for post-thoracotomy pain, were randomly allocated to receive infiltration of the ipsilateral phrenic nerve with either ropivacaine 0.2% 10 mL (ropivacaine, n = 25), or saline 0.9% (control, n = 25) just before lung expansion and chest closure. A blinded observer recorded the incidence and severity of ipsilateral shoulder pain 6, 12, 24, 36 and 48 h after surgery. Postoperative respiratory function was also evaluated with blood gas analyses. RESULTS: The cumulative incidences of ipsilateral shoulder pain during the first 24 h after surgery were 8/25 in the ropivacaine and 16/25 in the control groups (P = 0.047), with median (range) onset times for shoulder pain of 2 (2-24) h with ropivacaine and 0.5 (0.5-24) h in controls (P = 0.005). No differences were reported on the second postoperative day. The areas under the curves of the amount of pain over time were 0 (0-2760) mm h for the ropivacaine and 350 (0-1900) mm h for the control groups (P = 0.06). Postoperatively, similar reductions in indices of oxygenation were observed in both groups. CONCLUSIONS: Phrenic nerve infiltration with ropivacaine 0.2% 10 mL reduced the incidence and delayed the onset of ipsilateral shoulder pain during the first 24 h after open lung resection, with no clinically relevant effects on respiratory function.

A recovery room-based acute pain service.

AIM: Despite routine postoperative pain management improves recovery and reduces postoperative morbidity and overall costs, and the availability of a large armamentarium of analgesic techniques and drugs, a significant portion of patients do not receive adequate postoperative pain control. We describe a recovery room (RR) based acute pain service model. METHODS: Guidelines on postoperative pain and therapeutic protocols were instituted in January 1999. The analgesic endpoint was a visual analogic scale (VAS) below 4 for all surgical patients for the first 48-72 h. The RR, run by one anesthesiologist and 2 nurses and one assistant, acted as a coordination centre. Discharge from the RR was subject to achieving effective analgesia. Nurses of each ward monitored VAS along with vital signs, administered rescue doses if necessary, and reported to the RR nurse when needed. RR nurses monitored the patient at least twice daily and reported to the anesthesiologist. We have distributed an anonymous questionnaire, within surgical wards, to both surgeons and nurses to evaluate their perception of pain management and of this acute pain service (APS) model. RESULTS: VAS was maintained significantly <4. Analgesic drug consumption increased between 1997, 2000 (first year of APS) and 2004. The auditing process confirmed the desire of all professional figures to be informed and involved in acute pain management as part of a coordinated and systematic approach to the surgical patient. CONCLUSION: A RR-based APS can effectively act as coordinating centre for acute pain treatment without adjunctive personnel.

Monitoring cerebral oxygen saturation in elderly patients undergoing general abdominal surgery: a prospective cohort study.

BACKGROUND AND OBJECTIVES: The aim of this prospective, observational study was to evaluate changes in regional cerebral oxygen saturation (rSO2) and incidence of intraoperative cerebral desaturation in a cohort of elderly patients undergoing major abdominal surgery. METHODS: rSO2 was continuously monitored on the left and right sides of the forehead in 60 patients older than 65 yr (35 males and 25 females; ASA II-III; age: 72 +/- 5 yr; without pre-existing cerebral pathology, and baseline Mini Mental State Examination (MMSE) score >23) undergoing sevoflurane anaesthesia for major abdominal, non-vascular surgery >2 h. RESULTS: Baseline rSO2 was 63 +/- 8%; cerebral desaturation (rSO2 decrease <75% of baseline or <80% in case of baseline rSO2 <50%) occurred in 16 patients (26%). The MMSE decreased from 28 +/- 1 before surgery to 27 +/- 2 on 7th postoperative day (P = 0.05). A decline in cognitive function (decrease in MMSE score > or = 2 points one week after surgery as compared to baseline value) was observed in six patients without intraoperative cerebral desaturation (13.6%) and six patients who had intraoperative cerebral desaturation (40%) (P = 0.057) (odds ratio: 4.22; CI95%: 1.1-16). Median (range) hospital stay was 14 (5-41) days in patients with an area under the curve of rSO2 <50% (AUCrSO2<50%) >10 min%, and 10 (4-30) days in those with an AUCrSO2<50% <10 min% (P = 0.0005). CONCLUSIONS: In a population of healthy elderly patients, undergoing non-vascular abdominal surgery cerebral desaturation can occur in up to one in every four patients, and the occurrence of cerebral desaturation is associated with a higher incidence of early postoperative cognitive decline and longer hospital stay.

Does clonidine 50 microg improve cervical plexus block obtained with ropivacaine 150 mg for carotid endarterectomy? A randomized, double-blinded study.

STUDY OBJECTIVE: To evaluate the effects of adding 50 microg clonidine to 150 mg ropivacaine for superficial cervical plexus block in patients undergoing elective carotid endarterectomy (TEA). DESIGN: Randomized, double-blind study. SETTING: Departments of Anesthesia and Vascular Surgery of a university hospital. PATIENTS: 40 ASA physical status II and III patients undergoing elective TEA during superficial cervical plexus block. INTERVENTIONS: Superficial cervical plexus block was placed using 20 mL of 0.75% ropivacaine alone (Ropi group, n = 20) or with the addition of 50 microg clonidine (Ropi-Clonidine group, n = 20). If required, analgesic supplementation was given with local infiltration with 1% lidocaine and intravenous fentanyl (50-microg boluses). Nerve block profile, need for intraoperative analgesic supplementation, and time to first analgesic request were recorded. MEASUREMENTS AND MAIN RESULTS: Median (range) onset time was 10 minutes (5-25 min) in the Ropi group and 5 minutes (5-20 min) in the Ropi-Clonidine group (P < 0.05). Intraoperative consumption of both 1% lidocaine and fentanyl was higher in patients of the Ropi group (15 mL [0-25 mL] and 250 microg [50-300 microg]) than in patients of the Ropi-Clonidine group (8 mL [0-20 mL] and 0 microg [0-150 microg]; P < 0.05 and P < 0.05, respectively). First postoperative analgesic request occurred after 17 hours (10-24 hrs) in the Ropi group and 20 hours (10-24 hrs) in the Ropi-Clonidine group (P > 0.05). CONCLUSIONS: Adding 50 microg clonidine to 150 mg ropivacaine for superficial cervical plexus block shortened the onset time and improved the quality of surgical anesthesia in patients undergoing elective TEA.

Stimulating or conventional perineural catheters after hallux valgus repair: a double-blind, pharmaco-economic evaluation.

BACKGROUND: We prospectively evaluated direct analgesia-related costs of continuous sciatic nerve block using either a stimulating or conventional catheter after hallux valgus repair. METHODS: The perineural catheter was inserted through a stimulating introducer either blindly (group Conventional, n= 38) or while stimulating via the catheter (group Stimulating, n= 38). Nerve block was induced with 25 ml of mepivacaine 15 mg/ml, and was followed 3 h later by a patient-controlled infusion of ropivacaine 2 mg/ml (basal infusion: 3 ml/h; incremental dose: 5 ml; lock-out time: 30 min). Rescue tramadol [100 mg intravenous (i.v.)] was given if required. Local anesthetic consumption, need for rescue tramadol and post-operative nausea and vomiting (PONV) treatment, and patient's satisfaction were recorded during first 24-h infusion. Cost calculations were based on the acquisition cost of drugs and devices. RESULTS: Both techniques were similarly effective, but local anesthetic consumption and need for rescue analgesics were lower in the Stimulating group [respectively, 120 vs. 153 ml (P= 0.004) and 21% vs. 60% (P= 0.001)]. The analgesia-related costs for 24 h were similar when 100-ml bags of ropivacaine 2 mg/ml were used (66 euro vs. 67 euro; P= 0.26). When 200-ml bags of ropivacaine were used, the analgesia-related costs were higher in the Stimulating group than the Conventional group (75 euro vs. 55 euro; P= 0.0005). CONCLUSIONS: Direct costs of continuous sciatic nerve block ranged from 55 to 75 euro. Stimulating catheters reduced local anesthetic consumption and need for rescue analgesics. This was only cost effective when 100-ml bags of 2 mg/ml ropivacaine were used, while the cheapest combination was the use of conventional catheters and 200-ml bags of ropivacaine.

New technology for noninvasive brain monitoring: continuous cerebral oximetry.

Although the central nervous system is the primary endpoint of most general anesthetics, it is still the least monitored organ in clinical anesthesiology. In the last decade, technological research has expanded the application of near-infrared spectroscopy to allow continuous, non-invasive, and bedside monitoring of cerebral oxygen saturation (rSO(2)) through the scalp and skull, providing accurate information on the balance between brain oxygen supply and demand. The aim of this review is to provide an overview on relevant technological issues of cerebral oximetry, describe a systematic approach to its use, and summarize current information on its possible impact on our daily practice. We reviewed studies published on peer-reviewed journals about technological development and clinical application of rSO(2) monitoring in different fields of application to clinical practice. Due to the wide patient-to-patient variability of baseline rSO(2) values in each patient the baseline value should be determined before inducing general anesthesia, and cerebral ischemia is related more to the changes from baseline than to the absolute value: a reduction of 20% from baseline is usually accepted as clinical threshold of cerebral ischemia. If baseline rSO(2) is lower than 50% the critical threshold should be reduced to 15%. Routine use of rSO(2) monitoring in patients undergoing cardiac surgery to guide the anesthesia plan has been demonstrated to improve patient outcome and shorten hospital stay. However, rSO(2) monitoring does not seem to provide information accurate enough to indicate the placement of a Javid's shunt during carotid endarterectomy. In patients with neurological pathology or head trauma rSO(2) monitoring has been reported accurate enough in detecting early changes in cerebral blood flow that might result in cerebral ischemia. In aged patients undergoing major abdominal surgery rSO(2) monitoring to guide the anesthesia plan has been reported to reduce the exposition to cerebral ischemia with less effects on cognitive decline and shorter hospital stay. In conclusion several clinical conditions routinely encountered in our daily practice have the potential to disrupt the balance between the brain oxygen supply and demand, exposing to the risk of intraoperative cerebral ischemia. These alterations in brain oxygen balance remain totally undiagnosed if we do not specifically monitor it; while the possibility of monitoring regional cerebral oxygen saturation through a simple and totally non-invasive device has the potential for optimizing our anesthesia plan to the real needs of our main targeted organ: the brain.

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

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