Lockout Interval Research Articles

Efficacy of different low-doses of nalmefene in preventing remifentanil-induced postoperative hyperalgesia

Objective To evaluate the efficacy of different low-doses of nalmefene in preventing remifentanil-induced postoperative hyperalgesia. Methods One hundred American Society of Anesthesiologist physical status Ⅰor Ⅱpatients, aged 20-64 yr, wih body mass index of 18-25 kg/m2, scheduled for elective gynecological laparoscopic surgery under general anesthesia, were divided into 4 groups(n=25 each)using a random number table: control group(group C)and different doses of nalmefene groups(N1, N2 and N3 groups). In N1, N2 and N3 groups, nalmefene 0.2, 0.3 and 0.5 μg/kg(diluted to 5 ml in normal saline)were intravenously injected, respectively, at 5 min before anesthesia induction, while the equal volume of normal saline was given in group C. Anesthesia was induced with midazolam 0.05 mg/kg, sufentanil 0.3 μg/kg, etomidate 0.3 mg/kg and rocuronium 0.6 mg/kg.The patients were mechanically ventilated after tracheal intubation.Anesthesia was maintained by IV infusion of remifentanil 0.3 μg·kg-1·min-1 and inhalation of 4%-6% desflurane, bispectral index value was maintained at 45-60, and muscle relaxation was maintained with intermittent IV boluses of rocuronium.After admission to postanesthesia care unit, patient-controlled analgesia(PCA)was performed, and PCA solution contained sufentanil 1 μg/ml in 100 ml of normal saline.PCA pump was programmed to deliver a 0.5 ml bolus dose with a lockout interval of 15 min and background infusion at 2 ml/h.Numeric rating scale score was maintained <4.The time for remifentanil infusion was recorded.The consumption of sufentanil was recorded in 0-1, 1-3, 3-6, 6-12 and 12-24 h periods after surgery, and the occurrence of nausea, vomiting, tachycardia, hypertension and shivering was also recorded within 24 h after surgery. Results Compared with group C, the postoperative consumption of sufentanil was significantly reduced in 0-1 h and 1-3 h periods after surgery in group N1 and in 0-1, 1-3, 3-6 and 6-12 h periods after surgery in group N2, and the incidence of postoperative nausea was significantly decreased in N1, N2 and N3 groups(P<0.05). The consumption of sufentanil in 3-6 h period after surgery was significantly lower in group N2 than in group N1(P<0.05). Conclusion The optimal dose of nalmefene is 0.3 μg/kg when used to prevent remifentanil-induced postoperative hyperalgesia. Key words: Morphinane; Piperidines; Hyperalgesia

Intravenous dexamethasone as an adjunct to improve labor analgesia: A randomized, double-blinded, placebo controlled clinical trial

ObjectiveTo study the role of intravenous (i.v.) dexamethasone as an analgesic adjunct in labor analgesia. DesignDouble-blinded randomized controlled trial. SettingLabor analgesia in a tertiary-care teaching hospital. PatientsEighty consenting ASA I-II parturients, age>18year, nulliparous, single gestation, cephalic presentation at ≥36 wk. of gestation, in early spontaneous labor (cervical dilatation≤5cm) requesting epidural analgesia. InterventionsThe patients were randomized to two groups. The Dexa group received 8mg of dexamethasone i.v. in 50ml normal saline approximately 45min before the procedure. Placebo group patients received 50ml normal saline only. All patients underwent epidural labor analgesia per hospital protocol. After an initial bolus, they received continuous background infusion of 5ml/h of 0.1% of levobupivacaine with 2μg/ml of fentanyl, with the provision of patient controlled boluses of 5ml of the same drug combination with a lockout interval of 12min if needed. MeasurementsPrimary outcome measure: hourly average consumption of neuraxially administered levobupivacaine-fentanyl combination. Secondary outcomes and observations: pain score, maternal satisfaction, sensory and motor block characteristics, hemodynamic parameters of mother, fetal heart rate, duration of second stage of labor, mode of delivery, Apgar scores at 1 and 5min, and adverse effects. Main resultsAverage hourly drug consumption was significantly lower in Dexa group as compared to Placebo group (10.34±1.79ml/h vs. 11.34±1.83ml/h; mean difference 1.007, 95% CI 0.199–1.815; P=0.015). The median number of bolus doses was 4 (interquartile-range [IQR] 3–5.75) and 5 (IQR 3–6) in the Dexa and Placebo groups, respectively (P=0.162). There was no significant difference between groups with regard to pain scores, maternal satisfaction and hemodynamics, mode of delivery, and adverse effects. ConclusionsI.v. dexamethasone significantly decreased hourly average drug consumption of levobupivacaine-fentanyl combination through the epidural route, demonstrating the epidural drug dose sparing effect during labor analgesia.

Efficacy of ultrasound-guided continuous transverses abdominis plane block when used for postoperative analgesia in patients undergoing total hysterectomy

Objective To evaluate the efficacy of ultrasound-guided continuous transverses abdominis plane (TAP) block when used for postoperative analgesia in the patients undergoing total hysterectomy. Methods Forty American Society of Anesthesiologists physical status Ⅰ or Ⅱpatients, aged 38-64 yr, weighing 50-80 kg, undergoing elective total hysterectomy with general anesthesia, were divided into 2 groups using a random number table: continuous TAP block group (CTAP group, n=21) and patient-controlled intravenous analgesia (PCIA) group (n=19). In group CTAP, bilateral TAP block was performed with 0.2% ropivacaine 20 ml under ultrasound guidance before operation, and 0.2% ropivacaine 5 ml/h was infused into bilateral TAPs after extubation.In group PCIA, the patients received PCIA with sufentanil 1 μg/ml after extubation, and the PCIA pump was set up to deliver a 2 ml bolus dose, a 15 min lockout interval and background infusion at a rate of 2 ml/h.Analgesia lasted until 72 h after operation in both groups.When visual analog scale>4, morphine 5 mg was intramuscularly injected as rescue analgesic.The recovery time of postoperative intestinal function, length of hospital stay, patient′s satisfaction with analgesia, requirement for rescue analgesia, TAP block-related adverse reactions and development of postoperative nausea and vomiting were recorded.In group CTAP, blood samples were collected from the peripheral vein immediately after the end of operation and at 2, 6, 12, 24, 48 and 72 h after operation for determination of concentrations of ropivacaine in plasma and free ropivacaine in plasma using high-performance liquid chromatography. Results Compared with group PCIA, the requirement for rescue analgesia and incidence of nausea and vomiting were significantly decreased, the recovery time of postoperative intestinal function was shortened, the score for patient′s satisfaction with analgesia was increased (P 0.05). No TAP block-related adverse reactions were found in group CTAP.In group CTAP, the concentration of ropivacaine in plasma began to increase at 2 h after operation and peaked at 48 h after operation, the concentration of free ropivacaine in plasma began to increase at 2 h after operation and peaked at 24 h after operation (P<0.05). Conclusion Ultrasound-guided continuous TAP block produces good analgesic efficacy when used for the patients undergoing total hysterectomy. Key words: Nerve block; Transverses abdominis plane; Ultrasonography; Analgesia

Efficacy of lateral femoral approach to continuous sciatic nerve block for patient-controlled analgesia after foot and ankle surgery

Objective To evaluate the efficacy of lateral femoral approach to continuous sciatic nerve block for patient-controlled analgesia after foot and ankle surgery. Methods One hundred American Society of Anesthesiologists physical status Ⅰ-Ⅲ patients of both sexes, aged 18-60 yr, weighing 50-100 kg, with body height of 145-190 cm, scheduled for elective foot and ankle surgery, were divided into 2 groups (n=50 each) using a random number table: patient-controlled nerve block analgesia (PCNA) group and patient-controlled intravenous analgesia (PCIA) group.In group PCNA, the lateral femoral approach to sciatic nerve block was performed under the guidance of ultrasound and a neurostimulator, 0.2% ropivacaine 20 ml was injected after successful location, the catheter was inserted, and 0.2% ropivacaine 10 ml was injected again.In group PCIA, 0.2% ropivacaine 30 ml was injected after successful location of the sciatic nerve.General anesthesia was performed using laryngeal mask airway in both groups.In group PCNA, PCNA was performed with 0.2% ropivacaine (diluted to 200 ml in normal saline) at the end of surgery, and the PCNA pump was set up with a 0.5 ml bolus dose, a 15-min lockout interval and background infusion at a rate of 5 ml/h.In group PCIA, PCIA was performed with sufentanil 100 μg, tramadol 500 mg and tropisetron 10 mg (diluted to 200 ml in normal saline) at the end of surgery, and the PCIA pump was set up with a 0.5 ml bolus dose, a 15-min lockout interval and background infusion at a rate of 2 ml/h.The visual analog scale score was maintained≤3, and postoperative analgesia lasted until postoperative 72 h. When visual analog scale scores ≥ 4, tramadol 100 mg was intramuscularly injected as rescue analgesic.The requirement for rescue analgesia and development of adverse effects such as nausea and vomiting, insomnia, puncture site infection and bleeding were recorded within 72 h after surgery. Results The requirement for rescue analgesia and incidence of nausea and vomiting were significantly lower in group PCNA than in group PCIA (P<0.05). Conclusion The lateral femoral approach to continuous sciatic nerve block can be safely and effectively used for patient-controlled analgesia after foot and ankle surgery. Key words: Nerve block; Sciatic nerve; Analgesia, patient-controlled

Patient-controlled Intravenous Analgesia With Combination of Dexmedetomidine and Sufentanil on Patients After Abdominal Operation: A Prospective, Randomized, Controlled, Blinded, Multicenter Clinical Study.

Objective:To investigate the effect of combination of dexmedetomidine and sufentanil on patient-controlled intravenous analgesia (PCIA) in patients after abdominal operation and to assess the safety and validity of this treatment.Methods:This is a prospective, randomized controlled, blinded, multicenter clinical study. A total of 210 patients from 9 clinical research centers underwent selective abdominal operation with general anesthesia were enrolled in the study, including laparoscopic-assisted abdominal operation on stomach, intestines or open surgery on stomach, intestines, kidneys and liver, the American Society of Anesthesiologists status I to II. Patients were randomly assigned into 2 groups: control group (group C) sufentanil 100 μg+normal saline 100 mL in total and test group (group D) sufentanil 100 μg+ dexmedetomidine 200 μg+normal saline 100 mL in total. PCIA was set as follow: background infusion of sufentanil 2 μg/h, bolus dose of sufentanil 2 μg, lockout interval 5 minutes. Main measure indices were analgesic consumption, pressing times and effective pressing times of analgesic pump, usage count, and consumption of remedy drug. Validity indices were visual analog scale (VAS) scores and patient satisfaction. Drug safety indices were hemodynamic parameters, drug side effects, and anal exhaust time.Results:In total, 203 cases were analyzed. Seven cases were eliminated for incomplete data record. The total consumption of sufentanil (μg) in 24 hours after operation of group C and group D were 56.9±21.5 and 49.8±15.5, respectively, and the difference was statistically significant (P<0.05). Pressing times of analgesic pump in 24 hours after operation of group C and group D were 9.47±16.07 and 5.02±5.56 times, respectively, and the difference was statistically significant (P<0.05). Effective pressing times of analgesic pump in 24 hours after operation of group C and group D were 7.8±9.7 and 4.57±5.02 times, respectively, and the difference was statistically significant (P<0.05). Resting VAS scores and movement VAS scores at 2, 4, 8, and 24 hours postoperatively were statistically different (P<0.05). Usage times of rescue drug (pethidine) of group C and group D were 9 and 1, mean rank 118.13 and 85.71, respectively, and the difference was statistically significant (P<0.05). Mean rank of general satisfaction of group C and group D were 98.99 and 105.04, respectively, and the difference was statistically significant (P<0.05). Incidence rate of nausea in group C and group D within 24 hours after surgery was 25% and 12.5%, and of vomiting 18.2% and 6.25%, respectively and of vomiting and the difference was statistically significant.Conclusions:Compared with sufentanil PCIA alone, the combination of dexmedetomidine and sufentanil for PCIA after abdominal operation could reduce sufentanil consumption, decrease VAS scores, lower the rate of nausea and vomiting, and improve patient satisfaction.

Patient-controlled Intermittent Epidural Bolus Versus Epidural Infusion for Posterior Spinal Fusion After Adolescent Idiopathic Scoliosis

A prospective, randomized, double-blinded study. The aim of this study was to compare the efficacy and side effects of patient-controlled intermittent bolus epidural analgesia (PCIEA) and patient-controlled continuous epidural analgesia (PCCEA) for postoperative pain control in adolescent idiopathic scoliosis. Epidural analgesia is an accepted efficacious and safe procedure for postoperative pain management in scoliosis surgery. However, the PCIEA has not been adequately investigated for postoperative pain control in adolescent idiopathic scoliosis. Forty-seven patients, 8 to 18 years of age, who were undergoing posterior spinal fusion for idiopathic scoliosis were randomized to either the PCIEA or PCCEA group. An epidural catheter was inserted by a surgeon under direct visualization. The PCIEA group received 0.2 mg/mL of morphine, 0.25 mL/kg of morphine bolus, additional doses of 0.25 mL/kg morphine with a 1-hour lockout given by patient-controlled demand, and no infusion. The PCCEA group received the following: 0.2 mg/mL morphine, an initial morphine loading set at 0.1 mL/kg, followed by a 0.05 mL/kg/h continuous infusion of morphine, and a 0.025 mL/kg bolus dose of morphine. There was a 30-minute lockout interval. The primary outcome was morphine usage. The secondary outcomes were pain score, postoperative nausea and vomiting, and pruritus. Cumulative morphine consumption was lower in the PCIEA group than in the PCCEA group. Both methods provided effective pain control. There were no differences in pain scores between the groups. Postoperative nausea, vomiting, and pruritus were lower in the PCIEA group. The two epidural analgesia techniques studied are both safe and effective methods for postoperative pain control after posterior spinal fusion in idiopathic scoliosis. Nausea, vomiting and pruritus were considerably higher in the PCCEA group. Concerns regarding side effects associated with epidural opioids can be avoided by an intermittent bolus with a relatively lower amount of opioid. 2.

Dexmedetomidine in combination with sufentanil for postoperative analgesia after partial laryngectomy

BackgroundDexmedetomidine as an adjunct with opioids has been confirmed to spare opioids usage and improve analgesia for postoperative pain treatment. Furthermore, dexmedetomidine can attenuate the airway reflex. The aim of this study is to assess the safety and efficacy of dexmedetomidine combined with sufentanil for postoperative analgesia after partial laryngectomy.MethodsA total of 60 adult male patients were recruited and randomly allocated to receive sufentanil 1.0 μg ml−1 (Group S) or sufentanil 1.0 μg ml−1 plus dexmedetomidine 4 μg ml−1 (Group SD) for postoperative analgesia. The IV patient controlled analgesia (PCA) device was programmed to deliver 1.5 ml per demand with a 10 min lockout interval and 1.5 ml per hour background infusion. Cumulative consumption of sufentanil and pain intensity during 24 hour (h) after surgery were recorded. Coughing episodes per day, sleep quality, hemodynamic and respiratory profiles were measured.ResultsCompared with Group S, patients in Group SD required less sufentanil during the 0–24 h postoperative period (p < 0.0001) and reported significant lower pain intensity from the second postoperative hour to the end of the study (P < 0.0001). Daily coughing episodes, sleep disturbance was lower and patients’ satisfaction was higher in Group SD (P < 0.05). Decrease in heart rate and mean blood pressure from baseline at 1 h, 2 h, 3 h, 12 h, and 24 h after operation were significantly greater in Group SD (P = 0.00). The incidence of PCA related adverse events were comparable between the two groups.ConclusionDexmedetomidine/sufentanil combination for postoperatjve analgesia in partial laryngectomized patients resulted in significant sufentanil sparing, better analgesia, reduced frequency coughing episodes, and better sleep quality.Trial registrationChinese Clinical Registry (ChiCTR): ChiCTR-TRC-14004618, date of registration: 08 May 2014.

Gastrointestinal Tolerability With Oliceridine, A Novel µ Receptor G Protein Pathway Selective (µ-GPS) Modulator [4H

INTRODUCTION: Conventional opioids bind to μ receptors and non-selectively activate two intracellular signaling pathways. One (G protein pathway) is associated with analgesia. The second (β-arrestin pathway) is associated with opioid-related adverse events and inhibition of G protein-mediated analgesia. Oliceridine (TRV130) is a novel µ receptor G protein Pathway Selective (µ-GPS) modulator that activates G protein while causing low β-arrestin recruitment to the μ receptor. This novel mechanism of action could lead to a differentiated therapeutic profile of rapid/effective analgesia with improved safety and gastrointestinal tolerability than conventional opioids. METHODS: Subjects in a Phase 2 randomized control clinical trial with moderate-to-severe acute pain following abdominoplasty were assigned into one of 4 IV PCA treatment groups. All treatment groups incorporated a 6-minute PCA lockout interval and were: volume-matched placebo, morphine regimen (4 mg loading; 1 mg demand), oliceridine regimen A (1.5 mg loading; 0.10 mg demand), oliceridine regimen B (1.5 mg loading; 0.35 mg demand). RESULTS: Of the 200 subjects, demographics and baseline characteristics were similar between treatment groups. At equianalgesic dose, both regimens of oliceridine were associated with a significantly lower percentage of patients who experienced both nausea and vomiting versus morphine (13% and 13% versus 39%; p less than 0.05). No serious adverse events (AEs) reported for the 4 groups. CONCLUSION: In this study, both regimens of oliceridine had a significantly lower prevalence of gastrointestinal AEs versus morphine. This suggests that oliceridine may widen the therapeutic window between rapid/effective analgesia and gastrointestinal dysfunction. These results may extrapolate to obstetric and gynecologic procedures but further investigation is warranted.

Optimum dose of nalbuphine prepared for patient-controlled intravenous analgesia after caesarean section

Objective To determine the optimum dose of nalbuphine prepared for patient-controlled intravenous analgesia(PCIA)after caesarean section. Methods A total of 100 parturients, aged 22-40 yr, weighing 60-90 kg, of American Society of Anesthesiologists physical statusⅠor Ⅱ, at≥37 weeks of gestation, scheduled for elective caesarean section, were divided into 4 groups(n=25 each)using a random number table: sufentanil 2.0 μg/kg group(group S), nalbuphine 1.5 mg/kg group(group N1), nalbuphine 2.0 mg/kg group(group N2)and nalbuphine 2.5 mg/kg group(group N3). In S, N1, N2 and N3 groups, sufentanil 2.0 μg/kg and nalbuphine 1.5, 2.0 and 2.5 mg/kg were added to PCIA solution, respectively, tropisetron 12 mg was added, and PCIA solution was then diluted to 100 ml in normal saline.The PCA pump was set up to deliver a 1 ml bolus dose with a 10-min lockout interval and background infusion at 2 ml/h after a loading dose of 3 ml.Tramadol 50 mg was intravenously injected as a rescue analgesic to maintain visual analogue scale score at rest ≤4 or during activity(cough)≤6.The highest Ramsay sedation score, requirement for rescue analgesics, the number of unsuccessfully delivered doses, the number of attempts and occurrence of nausea and vomiting, pruritus and somnolence within 48 h after operation were recorded. Results Compared with group S, the number of unsuccessfully delivered doses, the number of attempts and requirement for rescue analgesics were significantly decreased in N2 and N3 groups, the incidence of somnolence and the highest Ramsay sedation scores were increased in group N3(P 0.05). Compared with group N1, the number of unsuccessfully delivered doses, the number of attempts and requirement for rescue analgesics were significantly decreased in N2 and N3 groups, and the incidence of somnolence and the highest Ramsay sedation scores were increased in group N3(P 0.05). Conclusion The optimum dose of nalbuphine prepared for PCIA after caesarean section is 2.0 mg/kg. Key words: Nalbuphine; Caesarean section; Pain, postoperative; Analgesia, patient-controlled

Postoperative analgesic efficacy of single-shot and continuous transversus abdominis plane block after laparoscopic cholecystectomy: A randomized controlled clinical trial

Study objectiveTo compare the analgesic efficacy of ultrasound-guided single-shot and continuous transversus abdominis plane (TAP) block to that of IV-PCA in patients undergoing laparoscopic cholecystectomy. DesignProspective randomized controlled trial. SettingPost-anesthesia care unit and General ward. Patients108 American Society of Anesthesiologist (ASA) physical status I-II patients undergoing laparoscopic cholecystectomy. InterventionsGroup A received IV-PCA; group B received both ultrasound-guided single-shot TAP block with 0.2% ropivacaine (20mL) and IV-PCA; and group C received continuous TAP block using an ultrasound-guidance-inserted indwelling catheter. In group C, infusion of 0.2% ropivacaine at a basal rate of 3mL/h, bolus dose of 4mL, and a lockout interval of 30min was maintained for 48h postoperatively. The primary outcome was evaluated analgesic efficacy using the numeric rating scale (NRS) for 48h postoperatively. Other outcomes included the number of patients requiring additional analgesics, patient satisfaction with postoperative pain control, and incidence of postoperative adverse events. Main resultsCompared to other groups, group C had higher deep abdominal NRS at 1h postoperatively (P<0.05), and lower incidence of postoperative urinary retention (P<0.05). There were no significant intergroup differences in the number of patients requiring additional analgesics, and patient satisfaction with postoperative pain control. ConclusionsCompared to IV-PCA with or without single-shot TAP block, ultrasound-guided continuous TAP block provided similar analgesia in somatic pain and less analgesia in visceral pain. Moreover, the latter resulted in a lower incidence of postoperative urinary retention.

I.V. Paracetamol as an Adjunct to Patient-Controlled Epidural Analgesia With Levobupivacaine and Fentanyl in Labour

Abstract Background Use of i.v. paracetamol for postoperative pain is well documented, but it is unclear if it can reduce the consumption of opioids during patient-controlled epidural analgesia (PCEA) in labouring parturients. Methods In this randomized, double-blind, placebo-controlled clinical trial conducted in a tertiary care hospital, 80parturients were randomly assigned to two groups of 40 each, to receive either 1000 mg (100 ml) i.v. paracetamol or 100 ml normal saline as placebo, 30 min before the procedure. After insertion of the epidural catheter, all patients received 10 ml of levobupivacaine 0.1% with 2 μg ml-1 fentanyl, followed by continuous background epidural infusion of 6 ml h-1 with a provision of patient-controlled bolus 5 ml of same drug with a lock-out interval of 12 min. The primary outcome was hourly mean consumption of levobupivacaine and fentanyl mixture (ml.h-1). Secondary outcomes included pain score, sensory and motor block, haemodynamic parameters of mother, duration of second stage of labour, mode of delivery, Apgar scores, foetal heart rate and adverse effects. Results The hourly mean drug consumption in the Paracetamol group was significantly lower as compared with the Placebo group (7.03 ml.h-1, SD 0.83 vs. 8.12 ml.h-1, SD 1.34; p Conclusions Use of 1000 mg i.v. paracetamol decreases the mean hourly drug consumption through epidural route. Thus i.v. paracetamol is a safe and effective adjunct to PCEA in labour analgesia. Clinical trial registration Clinical Trials Registry—India (http://ctri.nic.in/Clinicaltrials/login.php), trial registration number 2013/09/003968.

Comparison of continuous lumbar plexus block with different concentrations of dexmedetomidine added to ropivacaine for postoperative analgesia in elderly patients undergoing hip replacement

Objective To compare the efficacy of continuous lumbar plexus block(LPB)with different concentrations of dexmedetomidine added to ropivacaine for postoperative analgesia in elderly patients undergoing hip replacement. Methods Sixty elderly patients of both sexes, aged 65-85 yr, weighing 50-71 kg, of American Society of Anesthesiologists physical status Ⅱor Ⅲ, scheduled for elective total hip replacement, were divided into 2 groups(n=30 each)using a random number table: 0.5 μg/ml dexmedetomidine+ 0.1% ropivacaine group(group D1)and 1.0 μg/ml dexmedetomidine+ 0.1% ropivacaine group(group D2). Lumbar-sacral plexus block combined with general anesthesia was used.At the end of operation, LPB pump was started and set up to deliver a 4 ml bolus dose with a 30 min lockout interval and background infusion at a rate of 8 ml/h.The analgesia solution contained 0.5 μg/ml dexmedetomidine and 0.1% ropivacaine in group D1 and 1.0 μg/ml dexmedetomidine and 0.1% ropivacaine in group D2.Postoperative analgesia lasted for 48 h, and the visual analogue scale score was maintained ≤3.Patient-controlled intravenous analgesia(PCIA)pump was connected when break-through pain happened.PCIA solution contained morphine 50 mg diluted to 50 ml in 0.9% sodium chloride.PCIA pump was set up to deliver a 1 ml bolus dose with a 5 min lockout interval and no background infusion.When the visual analogue scale score >3, the patient-controlled LPB pump was used first, and 15 min later if analgesia was still ineffective, PCIA pump was applied.The number of patients in whom analgesia was effective and occurrence of adverse reactions were recorded. Results Compared with group D1, the rate of effective analgesia was significantly increased, and the incidence of nausea, vomiting and pruritus was decreased in group D2(P<0.05). No bradycardia, hypotension, over-sedation, respiratory depression, urinary retention or local skin infection was found in the two groups. Conclusion Continuous LPB with 1.0 μg/ml dexmedetomidine added to 0.1% ropivacaine provides better efficacy for postoperative analgesia in elderly patients undergoing hip replacement. Key words: Dexmedetomidine; Amides; Arthroplasty, replacement, hip; Nerve block; Lumbosacral plexus

Comparison of ropivacaine with and without fentanyl vs bupivacaine with fentanyl for postoperative epidural analgesia in bilateral total knee replacement surgery

Study ObjectivesPain after total knee replacement (TKR) interferes with early rehabilitation. Although the use of epidural bupivacaine in post-TKR patients is associated with effective analgesia, the associated motor blockade effect delays functional recovery. We compared analgesic efficacy and side effects of postoperative patient-controlled epidural analgesia (PCEA) with plain ropivacaine 0.1% with/without fentanyl 2.5 μg/mL vs plain bupivacaine 0.0625% with fentanyl 2.5 μg/mL in patients undergoing bilateral TKR. DesignProspective, double-blind, randomized study. SettingsOperation room, postoperative recovery room, and intensive joint replacement unit. PatientsNinety American Society of Anesthesiologists I to II post-TKR patients who were randomly allocated to receive postoperative PCEA with plain ropivacaine 0.1% (group 1), ropivacaine 0.1% with fentanyl 2.5 μg/mL (group 2), and plain bupivacaine 0.0625% with fentanyl 2.5 μg/mL (group 3). InterventionPostoperatively, the PCEA settings were standardized for a basal flow of 4 mL/h, demand dose of 6 mL, and lock-out interval of 20 minutes. “Rescue” analgesia included epidural boluses (6 mL) of respective study drug over and above PCEA administration. MeasurementsPostoperative pain profile, total PCEA drug used, heart rate, and noninvasive blood pressure, side effects, and patient satisfaction were recorded. Main resultsDemographic parameters, duration of surgery, and hemodynamic variables (heart rate and noninvasive blood pressure) were comparable for the 3 study groups. Pain scores and rescue drug requirements were greater in “ropivacaine-only” group. Motor blockade was greatest in “bupivacaine-fentanyl” group. Postoperatively, despite the presence of minor side effects (nausea, itching) in the “ropivacaine-fentanyl” and bupivacaine-fentanyl groups, the patients belonging to these groups were more satisfied. ConclusionAfter bilateral TKR, ropivacaine-fentanyl combination administered through a PCEA system resulted in “superior” analgesic efficacy, that is, pain relief without motor blockade, than “ropivacaine alone” (lesser pain relief) and bupivacaine-fentanyl (pain relief but with attendant motor blockade). Overall, the addition of fentanyl to epidural local anesthetic returned favorable postoperative analgesia profile and patient satisfaction with minor incidence of opioid-related side effects.

Effects of dexmedetomidine administered for postoperative analgesia on sleep quality in patients undergoing abdominal hysterectomy

Study objectiveTo evaluate the effects of postoperative dexmedetomidine infusion on sleep quality in patients undergoing abdominal hysterectomy. DesignRandomized, double-blind study. SettingPostoperative recovery area and ward. PatientsSixty patients of American Society of Anesthesiologists physical status I or II scheduled for elective hysterectomy were enrolled. InterventionsPatients in group C received sufentanil infusion (a continuous dosage of 0.02 μg kg−1 h−1, a bolus dose of 0.02 μg/kg, a 10-minute lockout interval), and patients in group D received combined infusion of sufentanil with dexmedetomidine (a continuous dosage of sufentanil 0.02 μg kg−1 h−1 with dexmedetomidine 0.05 μg kg−1 h−1, a bolus doses of sufentanil 0.02 μg/kg with dexmedetomidine 0.05 μg/kg, a 10-minute lockout interval). MeasurementsPolysomnography (PSG) was performed on the following 3 nights: the night before surgery (PSG1), the first night after surgery (PSG2), and the second night after surgery (PSG3). Postoperative pain scores using visual analog scoring scale, levels of sedation, and cumulative sufentanil consumptions were also recorded. ResultsAfter surgery, patients suffered from significant sleep disturbance with a lower sleep efficiency index and subjective sleep quality and a higher arousal index at PSG2 and PSG3. Compared with group C, postoperative administration of dexmedetomidine significantly improved the sleep efficiency index and subjective sleep quality. Although the rapid eye movement and N3 stage sleep did not differ between the 2 groups, the N1 stage and arousal index were lower and the N2 stage in group D at PSG2 and PSG3 was higher. Compared with group C, patients in group D have better pain relief with a lower visual analog scoring scale and cumulative sufentanil consumptions at 6, 24, and 48 hours after surgery. ConclusionsDexmedetomidine infusion not only offers effective analgesia but also improves postoperative sleep quality in patients undergoing hysterectomy.

Sufentanil sublingual formulation for the treatment of acute, moderate to severe postoperative pain in adult patients

ABSTRACTIntroduction: Sufentanil is a highly selective µ-opioid agonist commonly used by intravenous and intrathecal routes for acute pain. Sublingual sufentanil formulation for patient controlled analgesia (PCA) uses an innovative administration device that suspends a 15 µg nanotablet with a fixed lockout interval. The system is a non-invasive, less burdensome method of opioid delivery compared to intravenous and intrathecal routes. Sublingual nanotablet PCA transmucosal bioavailability is 59% and the meaningful analgesic onset time is 60 minutes.Areas covered: This paper focuses on the effectiveness, safety and feasibility of sufentanil PCA sublingual formulation for the management of postoperative pain. The paper is based on PubMed searches and the European Medicine Agency assessment report.Expert commentary: Under-treatment of acute pain is a substantial clinical problem. The initial experiences with the sublingual delivery system are encouraging. Sufentanil sublingual nanotablets intended for PCA device use are approved in Europe, and approval is pending in the United States.

I.V. paracetamol as an adjunct to patient-controlled epidural analgesia with levobupivacaine and fentanyl in labour: a randomized controlled study

BackgroundUse of i.v. paracetamol for postoperative pain is well documented, but it is unclear if it can reduce the consumption of opioids during patient-controlled epidural analgesia (PCEA) in labouring parturients. MethodsIn this randomized, double-blind, placebo-controlled clinical trial conducted in a tertiary care hospital, 80parturients were randomly assigned to two groups of 40 each, to receive either 1000 mg (100 ml) i.v. paracetamol or 100 ml normal saline as placebo, 30 min before the procedure. After insertion of the epidural catheter, all patients received 10 ml of levobupivacaine 0.1% with 2 μg ml-1 fentanyl, followed by continuous background epidural infusion of 6 ml h-1 with a provision of patient-controlled bolus 5 ml of same drug with a lock-out interval of 12 min.The primary outcome was hourly mean consumption of levobupivacaine and fentanyl mixture (ml.h-1). Secondary outcomes included pain score, sensory and motor block, haemodynamic parameters of mother, duration of second stage of labour, mode of delivery, Apgar scores, foetal heart rate and adverse effects. ResultsThe hourly mean drug consumption in the Paracetamol group was significantly lower as compared with the Placebo group (7.03 ml.h-1, SD 0.83 vs. 8.12 ml.h-1, SD 1.34; p < 0.001). The mean number of boluses taken were also significantly less in the paracetamol group (1.00, SD 0.93 vs. 1.43, SD 0.90; p = 0.036). Pain scores decreased in both the groups without significant inter-group differences. ConclusionsUse of 1000 mg i.v. paracetamol decreases the mean hourly drug consumption through epidural route. Thus i.v. paracetamol is a safe and effective adjunct to PCEA in labour analgesia. Clinical trial registrationClinical Trials Registry—India (http://ctri.nic.in/Clinicaltrials/login.php), trial registration number 2013/09/003968.

Abstract PR291

Background & Objectives: To evaluate the effect of oxycodone versus sufentanil on quality of recovery during early period after radical resection of esophageal carcinoma performed via video-assisted thoracoscope and laparoscope. Materials & Methods: before the end of surgery, oxycodone 0.05mg/kg was injected intravenously in group O, sufentanil 0.1 μg/kg was injected intravenously in group S. Patient-controlled intravenous analgesia (PCIA) was then used for postoperative analgesia at the end of surgery(lasting for 48h). PCIA solution contained oxycodone 0.75mg/kg in 100 ml of normal saline in group O. PCIA solution contained sufentanil 0.2μg/kg in 100 ml of normal saline in group S. The PCIA pump was set with 2 ml bolus dose, 15 min lockout interval and background infusion rate of 2 ml/h. At 6, 24, 48h after surgery, numeric rating scale (NRS) was used to assess the intensity of pain. When NRS scores ≥4, tromadol 1.5mg/kg injected intravenously was used as rescue analgesic. The global QoR-40 aggregate score were compared between the two groups. The requirement for rescue analgesics was recorded. The occurrence of nausea and vomiting was recorded. (the time of bowel function return, urocatheter tube removal, nasogastric tube removal after surgery) were recorded. Results: Compared with group S, group O produced better physical comfort scores(P<0.001), they also had more active, greater physical independence scores and had less pain 72 h after surgery(P<0.05), the global QoR-40 scores were significant increased (P<0.001). Compared with group S, the incidence of nausea and vomiting was significantly lower in group O (P<0.05). Compared with group S, the time of bowel function return, urocatheter tube removal, nasogastric tube removal after surgery were shorter in group O (P<0.05). Conclusion: Compared with sufentanil, oxycodone can improve the quality of recovery during the early period after radical resection of middle esophageal carcinoma performed via video-assisted thoracoscope and laparoscope. Disclosure of Interest: None declared

Abstract PR199

Background & Objectives: Remifentanil as a potent ultra short opioid agonist, rapidly metabolized in mother and fetus is becoming more and more popular in labor analgesia as alternative to neuroaxial analgesia. Recent studies comparing epidural with remifentanil analgesia showed us much better pain relieve scores in epidural analgesia; however there was no big difference in satisfaction scores in both groups. In this study, we compared maternal and neonatal side effects, as well as patient satisfaction. Materials & Methods: We analyzed 55 patients, ASA I, at term admitted for spontaneous labor and divided into two groups. The first group (30 patients) received continuous epidural infusion (0.1% Bupivacain and Fentanyl 2 μg/ml) 10 ml/h beginning immediately after the initial dose. The second group (25 patients) received iPCA with remifentanil titrated from 20 mcg up to a maximum bolus dose of 50 mcg with a lockout interval of 2 minutes. Our primary outcome was maternal and neonatal safety. We evaluate pulse oximetry (SpO2), heart rate, respiratory rate, sedation scores, Apgar scores and umbilical cord blood gas analysis. Supplementary oxygen was administered continuously during the respiratory monitoring period. The secondary outcome was efficacy evaluated through hourly pain scores and satisfaction scores (two different 10 point Visual Analoge Scales). Results: Mean SpO2 was lower in the remifentanil group 96.4% vs 98.2 for epidural group. No respiratory depression (respiration rate <9 or SpO2 <90%) was found in both groups. The Ramsay sedation scores were significantly higher in the remifentanil group, P < 0.0001. Apgar scores and neonatal respiratory outcomes were similar. As expected, remifentanil was inferior to epidural analgesia with respect to the pain scores at all time points, P < 0.0001. No significant difference between the two groups in maternal satisfaction (8.9 for the remifentanil group and 9.1 for the epidural group). Conclusion: IPCA with remifentanil provides satisfactory level of labor analgesia, with lower SpO2 and more sedation. It can be a viable alternative to epidural analgesia, but continuous monitoring and oxygen supply is mandatory.

Comparison of continuous epidural infusion and programmed intermittent epidural bolus in labor analgesia.

BackgroundThis study aims to investigate differences between continuous epidural infusion (CEI) and programmed intermittent epidural bolus (IEB) analgesia for the Chinese parturients undergoing spontaneous delivery and to approach their safety to parturients and neonates.MethodsTwo hundred healthy American Society of Anesthesiologists class I or II, term (≥37 weeks’ gestation), nulliparous women who requested analgesia for labor were recruited. Epidural analgesia was initiated with a solution of 0.15% ropivacaine 10 mL and maintained with 0.1% ropivacaine mixed with sufentanil 0.3 μg/mL by CEI at a rate of 5 mL/h combined with a patient-controlled epidural analgesia (PCEA) bolus of 5 mL of ropivacaine sufentanil mixture or IEB of 5 mL of ropivacaine sufentanil mixture combined with a PCEA bolus of 5 mL of ropivacaine sufentanil mixture. The lockout interval was 20 minutes in each arm between the CEI and the IEB group. After 20 minutes of first dosage, visual analog scale (VAS) score was obtained every 60 minutes. The maternal and fetal outcome and total consumption of analgesic solution were compared.ResultsThere was no difference in demographic characteristics, duration of first and second stages, delivery methods, sensory block, fetal Apgar scores, and the maternal outcomes between the CEI and IEB groups. There was a significant difference in VAS scores and epidural ropivacaine total consumption between the two groups (IEB vs CEI: 51.27±9.61 vs 70.44±12.78 mg, P<0.01).ConclusionThe use of programmed IEB mixed with PCEA improved labor analgesia compared to CEI mixed with PCEA, which could act as maintenance mode for epidural labor analgesia.

Effect of dexmedetomidine-assisted continuous femoral nerve block analgesia after total knee arthroplasty (TKA)

Objective To investigate the effects of dexmedetomidine on ropivacaine for continuous femoral nerve block (CFNB) analgesia after total knee arthroplasty (TKA). Methods Forty patients after TKA were randomly assigned into two groups of T and C (n=20 cases each group). All of the patients received spinal-epidural combined anesthesia, subarachnoid injection of 0.5% isobaric ropivacaine 3 ml, intraoperative epidural space according to the need of surgery an extra 0.375% ropivacaine paid for 3 to 5 ml. Postoperative analgesia with continuous femoral nerve block was performed in both groups, after the puncture of femoral nerve, group T was injected with 0.375% ropivacaine + dexmedetomidine mixed solution 20 ml (with dexmedetomidine 0.6 μg/kg), group C were injected with 0.375% ropivacaine 20 ml. Placement of continuous femoral nerve catheter, two groups of patients were performed operation continuous femoral nerve block analgesia and CFNB with 0.75% ropivacaine 50 ml, added saline diluted to 200 ml (each bag). Background infusion was 4 ml per hour; the demand dose was 4 ml in a lockout interval of 30 minutes. Two groups of patients were recorded rest visual analogue scale (RVAS) and passive visual analogue scale (PVAS) postoperative 6, 24, 48 and 72 h. Serum concentration of tumor necrosis factor-α (TNF-α), interleukin(IL)-1β and IL-6 were measured with double sandwich enzyme-linked immunosorbent assay (ELISA) method before anesthesia and postoperative in 24, 48, and 72 hours. Analgesia-related adverse reactions such as delirium, nausea and vomiting, urinary retention were record. Results Compared to group C, postoperative RVAS and PVAS of 6, 24 and 48 h wrere significantly decreased (P<0.05). Postoperative serum concentrations of TNF-α, IL-1β and IL-6 in 24, and 48 hours in group T were lower than those in group C (P<0.05). Group T incidence of postoperative sinus bradycardia was lower than the group C (P<0.05). Conclusions Dexmedetomidine combined with ropivacaine analgesia may effectively improve the TKA postoperative analgesic effect of CFNB, to reduce the levels of serum inflammatory factors, and depress stress reaction after operation. Key words: Dexmedetomidine/AD; Procaine/AD; Femoral nerve; Nerve block; Arthroplasty, replacement, knee; Analgesia