First Request For Postoperative Analgesia Research Articles

The safety and efficacy of ultrasound-guided erector spinae plane block in postoperative analgesic of PCNL: A systematic review and meta-analysis.

The patients received percutaneous nephrolithotomy (PCNL) with severe postoperative pain and discomfort. The erector spinae plane block (ESPB), as a new anesthesia method of plane block, has a positive effect on postoperative analgesia. But evidence of ESPB in PCNL is still lacking. The objective of this study was to systematically analyze the postoperative analgesic effect of ESPB in patients receiving PCNL. The literature searching was conducted in PubMed, EMBASE, Cochrane Library and Clinical Trial Database (clinicaltrials.gov). Two independent researchers screened the included studies and extracted data. Meta-analysis was conducted by using the random-effect model with 95% confidence intervals. Chi-squared test with a significance level of 0.1 was utilized to evaluate the heterogeneity of included studies. The subgroup analysis and meta-regression analysis were conducted in studies with high heterogeneity. The publication bias was assessed based on whether there were discrepancies between prospective trial registration and reported protocols. There were 8 studies involving 456 patients assessing the efficacy of ESPB in reducing postoperative pain score of PCNL compared with no block or other blocks, such as subcutaneous infiltration, general anesthesia or TPVB intrathecal morphine. ESPB was a significantly effective and safe anesthesia method, which not only improved postoperative pain response (MD -1.76; 95% CI -2.57 to -0.94; I 2 = 85%; p<0.01), but also reduced analgesic consumption (MD -16.92; 95% CI -26.25 to -7.59; I 2 = 92.2%; p<0.01) and prolonged the time of first request for postoperative analgesia (MD 93.27; 95% CI 35.79 to 150.75; I 2 = 85.3%; p = 0.001) in patients receiving PCNL without significant postoperative complications (MD 0.80; 95% CI 0.31 to 2.03; I 2 = 0%; p = 0.404). Compared with no block or other blocks, the ESPB was a safe and effective anesthesia for patients receiving PCNL.

ANALGESIC EFFICACY OF BILATERAL ULTRASOUND GUIDED ERECTOR SPINAE PLANE BLOCK IN LUMBAR SPINE SURGERIES

Background: Pain after lumbar spine surgery is often difficult to control in the postoperative period. Traditionally, opioids have been the mainstay of treatment but are associated with many unwanted side effects and prolonged hospital stay. The ultrasound-guided erector spinae plane block (ESPB) is a relatively safe, simple technique. However, there are few controlled studies evaluating its efficacy. Objective: To evaluate the analgesic efficacy of bilateral ultrasound-guided erector spinae plane block in lumbar spine surgeries. Patients and Methods: This study included 50 patients of both sexes admitted for lumbar surgery at the Al-Hussein University Hospital from December 2019 to August 2020. They were randomly allocated into two groups: Control group (general anesthesia without ESPBP), and ESPB Group: included general anesthesia and bilateral ultrasound-guided erector spinae plane block. The following parameters were assessed in the two studied groups: Heart rate, mean arterial blood pressure, arterial oxygen saturation, end-tidal CO2, recovery profile, time of patient ambulation, visual analog score pain scores (VAS), Ramsay Sedation Scale scores, first request for postoperative analgesia, adverse events, the level of the patient satisfaction, and total dose of postoperative nalbuphine consumption. Results: This study showed a significant statistical difference regarding the postoperative VAS pain scores between the two groups. Patients who received ESPB had improved post-operative analgesia, better patients’ satisfaction, and earlier patient ambulation. Conclusion: Bilateral ultrasound-guided erector spinae plane block in lumbar spine surgeries is one of the most advantageous adjuvant blocks for improving post-operative pain relief and reducing opioid use and subsequently side effects.

The Effect of Pectoral Nerves Blocks on Narcotic Consumption and Pain Intensity in the Patients Undergoing Breast Cancer Surgery

Background: To decrease postoperative pain (PP) control, opioid requirement, and outcome improvement, regional anesthesia or preoperative analgesia is routinely performed as an alternative to general anesthesia. Thoracic wall nerve blocks, such as the pectoral nerves (PECS) block have recently become popular for preoperative pain control in patients undergoing breast cancer (BC) surgery. Objectives: The current study was designed to evaluate the effect of PECS anesthesia on the fentanyl and propofol consumption, as well as time to the first request to analgesia in the patients with BC surgery. Methods: A total of 22 women aged 20 to 75 years old with biopsy-proven BC were randomized to receive either propofol general anesthesia with PECS or total intravenous anesthesia without PECS in a randomized clinical trial. Total propofol and fentanyl dose and time to the first request for postoperative analgesia were assessed and compared in both groups. Results: The obtained data showed no significant difference in the total dose of fentanyl and propofol between the two groups. However, the PECS group showed a significant increase in time to the first request for postoperative analgesia. Conclusions: The PECS block in combination with general anesthesia for BC surgery significantly increased time to the first request to analgesia and was effective for reducing PP in the recovery room. PECS block combined with general anesthesia did not reduce the intraoperative use of fentanyl and propofol compared with the control group injected with normal saline.

Intra-articular dexmedetomidine in knee arthroscopy: A systematic review and meta-analysis

The aim of this meta-analysis is to evaluate the analgesic effects of intra-articular dexmedetomidine (DEX) in arthroscopic knee surgery. A comprehensive literature search was conducted to identify randomized controlled trials (RCTs) comparing intra-articular DEX versus control for postoperative analgesia in knee arthroscopy. Trial sequential analysis (TSA) was applied to determine the reliability of the evidence. Twelve RCTs including 594 patients met the eligibility criteria. DEX treatment significantly improved postoperative pain outcomes, with weighted mean differences (95% confidence interval) between the DEX and control groups of −1.57 (−1.94 to −1.20, P < 0.00001) for pain scores at rest at postoperative 1 h, −8.54 mg (−11.96 to −5.13, P < 0.00001) for morphine-equivalents at postoperative 0–24 h, and 257.57 min (209.86 to 305.28, P < 0.00001) for time to first request for postoperative analgesia. TSA indicated there is sufficient evidence for these outcomes. Intra-articular DEX did not affect the incidence of postoperative nausea and vomiting, hypotension, bradycardia, or somnolence. This meta-analysis demonstrated that intra-articular administration of DEX improved pain outcomes in the early postoperative period after knee arthroscopy. Due to the limited number of trials and patients included in this meta-analysis, more evidence is required to confirm these findings.

Effect of the use of dexmedetomidine as an adjuvant in peribulbar anesthesia in patients presented for vitreoretinal surgeries

BackgroundDexmedetomidine, if used in combination with a local anesthetic mixture in peribulbar anesthesia, may alter the block characteristic. This research aimed to study the influence of adding dexmedetomidine to local anesthetics in the peribulbar block.MethodsSixty adult patients of both gender presented for vitreoretinal surgeries were enrolled in this prospective double-blinded study. They were randomly distributed into two equal groups. All the patients received peribulbar anesthesia with 10ml mixture composed of 4ml of plain bupivacaine 0.5%, 4ml of lidocaine 2 % containing 50IU hyaluronidase, and either 2ml of normal saline (Control group) or 20 μg dexmedetomidine in (Dexmedetomidine group). The onset, the duration, and quality of sensory and motor blockade and the perioperative sedation were recorded.ResultsAs compared to the control group, dexmedetomidine when added to a local anesthetics in peribulbar block, significantly decreased the onset of anesthesia to 2.40 ± 1.50min, fastened the onset of the lid akinesia to 2.93 ± 2.07min and globe akinesia to 2.87 ± 1.96min, increased the duration of lid akinesia to 137.00 ± 17.94min and globe akinesia to 166.50 ± 21.34min, and increased the time of the first request for postoperative analgesia to 185.83 ± 30.80min (P< .05). Also, it significantly increased the level of patients sedation (P< .05).ConclusionA small dose of dexmedetomidine added to a local anesthetic mixture in peribulbar block improved the sensory and motor block criteria with increased level of patients sedation.

The effects of perineural dexmedetomidine on the pharmacodynamic profile of femoral nerve block: a dose-finding randomised, controlled, double-blind study.

This randomised, controlled, double-blind study investigated the effects of different doses of perineural dexmedetomidine on the pharmacodynamic profile of femoral nerve block in patients undergoing arthroscopic knee surgery. Ultrasound-guided femoral nerve block was performed before general anaesthesia using 25ml of bupivacaine 0.5% combined with normal saline in the control group, and 25μg, 50μg or 75μg of dexmedetomidine in three treatment groups (n=15 for each group). All patients received a standard general anaesthetic and multimodal postoperative analgesic regimen. The use of the 50μg and 75μg dose levels of dexmedetomidine was associated with reduction of the onset time, extension of the duration of block, prolonged time to the first postoperative request for rescue analgesia, and reduced postoperative morphine requirements. The times to first request for postoperative analgesia were mean (SD) 10.8 (1.6)h in the control group and 11.0 (7.1), 21.8 (3.0) and 28.6 (10.0) in the 25μg, 50μg and 75μg treatment groups, respectively. These times were significantly longer in the 50μg and 75μg treatment groups compared with the 25μg (p<0.0001) and control group (p<0.0001). The total 24-h postoperative morphine consumption was 7.6 (5.1)mg in the control group, and 6.5 (3.5), 3.9 (3.4), 1.8 (2.6) in the 25μg, 50μg and 75μg treatment groups, respectively. Postoperative morphine consumption was significantly higher in the control group compared with the 50μg (p=0.045) and the 75μg (p=0.001) treatment groups. The best analgesic profile was achieved at the 75μg dose, but this was associated with increased risk of hypotension.

The effects of adding epinephrine to ropivacaine for popliteal nerve block on the duration of postoperative analgesia: a randomized controlled trial.

BackgroundDuration of peripheral nerve blocks depends on multiple factors. Both technique and type of local anesthetic used, either with or without adjuncts, may result in different duration times of the block. The purpose of the present study was to compare the duration of postoperative analgesia of 30 mL ropivacaine 0.75 % with or without epinephrine for popliteal sciatic nerve block.MethodsThirty-eight patients were included to receive ultrasound guided continuous popliteal nerve block with ropivacaine 0.75 % either without (ROPI) or with epinephrine 5 μg/mL (ROPI-EPI) for ankle fusion, subtalar fusion, or a combination of both. The primary outcome parameter was the duration of postoperative analgesia as reflected by the time to first request for postoperative analgesia (TTFR) through the popliteal nerve catheter. Secondary outcome measures included the onset of sensory and motor block and NRS score for pain at rest and during movement.ResultsThirty patients, 15 in each group, were studied. Eight patients were withdrawn because of specific withdrawal criteria described in the protocol and replaced according to their group allocation. Median [interquartile range] TTFR was 463 [300–1197] min and 830 [397–1128] min for the ROPI vs ROPI-EPI group respectively. Hodges Lehman median difference between groups was 71 min (95 % CI −415 – 473 min). There was no difference in any clinical outcome measure between the groups.ConclusionThe results of this study did not show any significant increase in the duration of postoperative analgesia by adding epinephrine to ropivacaine for popliteal nerve block. This may be due to the intrinsic vasoconstrictive properties of ropivacaine. The absence of a significant difference can also be the result of a type II error caused by a large variation in the individual TTFR.Trial registrationTrial register.nl identifier: NTR3330, keyword TTFR

Comparison of the preemptive analgesia of low dose ketamine versus magnesium sulfate on parturient undergoing cesarean section under general anesthesia

ObjectiveTo investigate the efficacy of the preemptive analgesic effect of low dose ketamine versus MgSO4 on potentiating postoperative analgesia when compared to placebo in patients undergoing cesarean section under general anesthesia.MethodsThis prospective randomized blind study included 60 parturient females scheduled for cesarean section under general anesthesia. They were randomized into three equal groups [20 patients each]: group I [Control]: received 20 ml normal saline 0.9%, group II [Ketamine]: received ketamine 0.3 mg/kg in 20 ml normal saline and group III [MgSO4]: received MgSO4, 30 mg/kg in 20 ml normal saline. Investigated medications infused over 10 min before induction of anesthesia. Fentanyl requirement, mean BP and HR were measured intraoperatively. Pain, sedation and nausea and vomiting were assessed at 2, 6, 12 and 24 h postoperatively. Total postoperative pethidine dose over 24 h was calculated.ResultsMBP and HR showed statistically significantly lower value in group (K) and (M) compared to group (C) at postintubation and postincision readings. Intraoperative fentanyl requirement was statistically higher in (C) groups compared to (K) and (M) groups. The time for first request for postoperative analgesia was longer and the total postoperative pethidine dose over 24 h was lower in (K) group compared to (C) and (M) groups. Postoperative VAS scores at 2 and 6 h postoperatively showed statistically highly significantly lower values in (K) group compared to (C) and (M) groups. Apgar, postoperative sedation and PONV scores showed no statistically significant differences among the three groups.ConclusionsPreemptive dose of either ketamine (0.3 mg/kg) or MgSO4 (30 mg/kg) in patients undergoing cesarean section under general anesthesia could suppress the pressor response to endotracheal intubation and skin incision and decreased the intraoperative fentanyl requirement. Ketamine showed a significant preemptive analgesic effect compared to MgSO4 at 2 and 6 h postoperatively.

Pre-emptive peritonsillar dexamethasone vs. levobupivacaine infiltration for relief of post-adenotonsillectomy pain in children: A controlled clinical study

ObjectivesTo investigate the effects of the pre-emptive local infiltration of dexamethasone vs. levobupivacaine on postoperative pain and morbidity in pediatric adenotonsillectomy patients. MethodsA total of 60 patients (32 males and 28 females), aged 3–14 years, were included in this double-blind prospective randomized controlled clinical study from September of 2011 until May of 2012. Patients admitted for adenotonsillectomies after informed consent was obtained from the parents, and randomized into three groups receiving either dexamethasone sodium phosphate (Group 1, mean age 5.9±1.6), levobupivacaine with epinephrine (Group 2, mean age 6.1±2.6), or saline (Group 3, mean age 6.0±3.4). Pain scores at the 1st, 4th, 8th, 12th, 16th, and 20th hours, and first, second, third and seventh days post-operatively were recorded by the parents using McGrath’s face scale. The operation type, operation time and anesthesia time, the time of the first request for postoperative analgesia, and the total number of analgesic interventions were recorded. ResultsPain scores were revealed in this order: Group 1 (steroid)<Group 2 (levobupivacaine)<Group 3 (saline) at all times (p=0.000). The anesthesia times for Group 1 and Group 2 were different (steroid vs. levobupivacaine), and the time to first analgesic was longer in Groups 1 (steroid) and 2 (levobupivacaine) than in Group 3 (saline) (p<0.000). The total number of analgesic interventions was lower in Group 1 (steroid) than in Group 2 (levobupivacaine) and Group 3 (saline) (steroid vs. saline, p=0.000, and steroid vs. levobupivacaine, p<0.05). ConclusionPeritonsillar dexamethasone infiltration was more effective than both levobupivacaine and saline in reducing post-tonsillectomy pain. It was proven to be a safe and effective method.

Effects of Intravenous and Intrathecal Dexmedetomidine in Spinal Anesthesia: A Meta‐Analysis

To assess the effects of dexmedetomidine on the duration of sensory and motor block, postoperative analgesia, hypotension, bradycardia, and side effects in patients undergoing spinal anesthesia. Two researchers searched MEDLINE, EMBASE, and the Cochrane controlled trial register independently for randomized controlled trials comparing dexmedetomidine with a placebo without any language restrictions. A total of 412 patients from eight trials were included in this study. The results revealed that dexmedetomidine was statistically significant in prolonging the duration of sensory block (mean difference, MD=73.55; 95% CI, [55.69, 91.40] P<0.00001, I(2) =89%) and motor block (MD=59.11; 95% CI, [29.58, 88.65] P<0.00001, I(2) =91%) and the time to first request for postoperative analgesia (MD=245.77, 95% CI, [143.53, 348.00] P<0.00001, I(2) =98%). The occurrence of hypotension (OR=0.60, 95% CI, [0.3-1.23], P=0.40, I(2) =3%) and side effects (OR=0.9, 95% CI, [0.36-2.22], P=0.88, I(2) =0%) was not significantly different between dexmedetomidine and placebo. However, dexmedetomidine was associated with more frequent bradycardia requiring atropine (OR=7.55; 95% CI, [2.76-20.63], P=0.63, I(2) =0%). This meta-analysis has shown that dexmedetomidine prolonged the duration of spinal anesthesia and improved postoperative analgesia and did not increase the incidence of hypotension and adverse events, but needs more atropine to reverse bradycardia.

Can Intravenous Dexmedetomidine Prolong Bupivacaine Intrathecal Spinal Anesthesia?

Background and objectives: Different adjuvants have been used to prolong intrathecal spinal anesthesia, with the possible advantages of delayed onset of post-operative pain, delayed and reduced analgesic requirements. The aim of this study was to evaluate the effect ofintravenous dexmedetomidine on prolongation of intrathecal spinal anesthesia, level of sedation, post-operative analgesic requirement. Methods: Ninety adult patients classified as American Society of Anaesthesiologists physical status (ASA) I or II scheduled for various elective surgical proceduresbelow umbilicus under intrathecal spinal anesthesia were doubleblind randomized to one of three groups. Each patient received 0.5% hyperbaric bupivacaine 2.5 ml intrathecal spinal anesthesia. Group C (control): Patient receiving intravenous normal saline 10 ml over 10 mins (as placebo) 10 minutes before intrathecal spinal anesthesia with 0.5% hyperbaric bupivacaine 2.5 ml and normal saline 10 ml over 10 mins (as placebo) after 30 minutes of spinal anesthesia. Group D1: Patient receiving intravenous dexmedetomidine 1 μg/kg over 10 mins, 10 minutes before intrathecal spinal anesthesia. Group D2: Patient receiving intravenous dexmedetomidine 1 μg/kg over 10 mins after 30 minutes of intrathecal spinal anesthesia. Results: Sensory block was higher in group D2 (T-4.1 ± 0.7) than D1 (T-4.5 ± 0.5) and C (T-6.3 ± 0.8). Time for sensory regression of two blocks was 145 ± 32, 142 ± 28 and 94 ± 26 min in group D2, D1 and C respectively. Duration of motor block was similar in all groups. GroupD2 and D1 increased the time to first request for postoperative analgesia by 190.3 ±13.3 and 174 ± 19.5 min whereas in group C 133.40 ±10.4 min. The maximum Ramsay sedation score was greater in the group D1 and D2 than in C. Conclusion: Intravenous dexmedetomidine prolonged spinal bupivacaine sensory blockade in both the groups. It also provided sedation and additional analgesia.

Effects of intravenous dexmedetomidine on low‐dose bupivacaine spinal anaesthesia in elderly patients

Dexmedetomidine (DMT) has been shown to prolong spinal anaesthesia. We evaluated the effects of intravenous DMT on low-dose bupivacaine spinal anaesthesia in elderly patients. Fifty-one elderly patients undergoing transurethral resection of the prostate were randomized into two groups receiving either 1.0 μg/kg DMT (DMT group, n = 26) or normal saline (control group n = 25) intravenously prior to spinal anaesthesia with 1.2 ml of bupivacaine, 5 mg/ml. The mean time to two-segment regression (39 min vs. 78 min for cold, 41 min vs. 61 min for pinprick) and that to motor regression (23 min vs. 46 min) were longer in the DMT group than in the control group. The atropine-requiring bradycardia was more frequent in the DMT group than in the control group (24.0% vs. 3.8%). The median sedation scores (ranges) during surgery were 4 (2-6) in the DMT group and 2 (1-3) in the control group (P < 0.001). Two patients in the DMT group showed oxygen desaturation (peripheral oxygen saturation < 90%) during surgery. The duration of post-operative care unit stay was longer in the DMT group than in the control group (58 min vs. 96 min). Post-operative pain intensity was lower and the mean time to first request for post-operative analgesia was longer in the DMT group compared to the control group (6.6 h vs. 2.1 h). Intravenous DMT prolonged the duration of spinal anaesthesia and improved post-operative analgesia. However, more profound sedation with desaturation was observed with more frequent bradycardia, and delayed recovery should be considered in elderly patients.

Combined spinal epidural and epidural volume extension: Interaction of patient position and hyperbaric bupivacaine

Background:Previous trials have documented failure of block augmentation with epidural volume extension, when applied after the intrathecal injection of hyperbaric bupivacaine was made in sitting position. However, there is no study comparing the effect of change in patient position during block performance, on the results of epidural volume extension.Materials and Methods:The study was conducted in two parts in American Society of Anesthesiologists physical status I or II parturients scheduled for elective cesarean section under regional anesthesia. In the first part, 28 patients were randomized to one of the two groups, depending on whether epidural volume extension was applied following the block in sitting (group SE) or lateral position (group LE) (n=14 each). In the second part of the study another 28 patients were recruited and randomized to receive the block in sitting (group S) or lateral (group L) position (n=14 each), without epidural volume extension. All patients received combined spinal epidural block using needle-through-needle technique with intrathecal injection of 9 mg hyperbaric bupivacaine (0.5%) and 10 μg fentanyl. Epidural volume extension was performed using 5 ml normal saline in groups SE and LE.Results:In the first part of the study, the maximum sensory block level was higher in group LE vs. SE (P<0.05). In the second part of the study, no significant difference was seen in the maximum sensory level between group S and group L (P>0.05).Conclusions:If epidural volume extension is being applied with intention of rapid extension of sensory block when hyperbaric bupivacaine has been injected intrathecally, the combined spinal epidural block should be performed in lateral position rather than in the sitting position.

Intravenous dexmedetomidine, but not midazolam, prolongs bupivacaine spinal anesthesia

Midazolam has only sedative properties. However, dexmedetomidine has both analgesic and sedative properties that may prolong the duration of sensory and motor block obtained with spinal anesthesia. This study was designed to compare intravenous dexmedetomidine with midazolam and placebo on spinal block duration, analgesia, and sedation in patients undergoing transurethral resection of the prostate. In this double-blind randomized placebo-controlled trial, 75 American Society of Anesthesiologists' I and II patients received dexmedetomidine 0.5 microg . kg(-1), midazolam 0.05 mg . kg(-1), or saline intravenously before spinal anesthesia with bupivacaine 0.5% 15 mg (n = 25 per group). The maximum upper level of sensory block and sensory and motor regression times were recorded. Postoperative analgesic requirements and sedation were also recorded. Sensory block was higher with dexmedetomidine (T 4.6 +/- 0.6) than with midazolam (T 6.4 +/- 0.9; P < 0.001) or saline (T 6.4 +/- 0.8; P < 0.001). Time for sensory regression of two dermatomes was 145 +/- 26 min in the dexmedetomidine group, longer (P < 0.001) than in the midazolam (106 +/- 39 min) or the saline (97 +/- 27 min) groups. Duration of motor block was similar in all groups. Dexmedetomidine also increased the time to first request for postoperative analgesia (P < 0.01 compared with midazolam and saline) and decreased analgesic requirements (P < 0.05). The maximum Ramsay sedation score was greater in the dexmedetomidine and midazolam groups than in the saline group (P < 0.001). Intravenous dexmedetomidine, but not midazolam, prolonged spinal bupivacaine sensory blockade. It also provided sedation and additional analgesia.

Evaluation of a Single-Dose, Extended-Release Epidural Morphine Formulation for Pain After Knee Arthroplasty

DepoDur is a single-dose, extended-release epidural morphine formulation designed to provide forty-eight hours of pain relief. The drug offers potential advantages over continuous epidural infusions, particularly in patients being treated with anticoagulation therapy. The purpose of this study was to evaluate the efficacy and safety of single-dose epidural DepoDur for pain control following knee arthroplasty. In this multicenter, randomized, double-blind, parallel-group study, patients were randomized to receive a single-dose of DepoDur (20 or 30 mg) or a sham epidural injection thirty minutes before administration of general or regional anesthesia for knee arthroplasty. At their first request for postoperative analgesia, patients who had received DepoDur were given an intravenous bolus of hydromorphone followed by placebo patient-controlled analgesia. Patients who had received the sham epidural were given an intravenous bolus of morphine followed by patient-controlled analgesia with morphine. Patient ratings of pain intensity at rest and with activity, their rating of overall pain control, and postoperative opioid use were recorded. The ability to tolerate physical therapy, the range of motion of the knee, and the need for physical support were assessed as well. Adverse events and vital signs were recorded. Of 168 patients randomized to receive the 20-mg injection of DepoDur, the 30-mg injection of DepoDur, or the sham epidural injection, fifty-one, fifty-eight, and fifty-five patients, respectively, were included in the efficacy analysis. Compared with the patients treated with intravenous patient-controlled analgesia with morphine, the patients treated with DepoDur had significantly reduced mean pain-intensity-recall scores during the four to eight, four to twelve, four to twenty-four, and four to thirty-hour postdose intervals (p < 0.05 for all comparisons). The patients treated with DepoDur used approximately a threefold lower amount of postoperative opioids in total, with a significant percentage requiring no supplemental opioids. Adverse events common to all groups were nausea (78%), pyrexia (46%), vomiting (43%), pruritus (43%), and hypotension (36%). Respiratory depression was the most common serious adverse event, with serious respiratory depression observed in four DepoDur-treated patients, who were more than sixty-five years of age. With appropriate patient selection and monitoring, perioperative single-dose epidural DepoDur was a safe and effective analgesic alternative to postoperative intravenous patient-controlled analgesia following knee arthroplasty, with younger patients benefiting from the 20-mg dose. Additional studies of 10 to 15-mg doses for older patients are warranted.

EVALUATION OF A SINGLE-DOSE, EXTENDED-RELEASE EPIDURAL MORPHINE FORMULATION FOR PAIN AFTER KNEE ARTHROPLASTY

Background: DepoDur is a single-dose, extended-release epidural morphine formulation designed to provide forty-eight hours of pain relief. The drug offers potential advantages over continuous epidural infusions, particularly in patients being treated with anticoagulation therapy. The purpose of this study was to evaluate the efficacy and safety of single-dose epidural DepoDur for pain control following knee arthroplasty. Methods: In this multicenter, randomized, double-blind, parallel-group study, patients were randomized to receive a single-dose of DepoDur (20 or 30 mg) or a sham epidural injection thirty minutes before administration of general or regional anesthesia for knee arthroplasty. At their first request for postoperative analgesia, patients who had received DepoDur were given an intravenous bolus of hydromorphone followed by placebo patient-controlled analgesia. Patients who had received the sham epidural were given an intravenous bolus of morphine followed by patient-controlled analgesia with morphine. Patient ratings of pain intensity at rest and with activity, their rating of overall pain control, and postoperative opioid use were recorded. The ability to tolerate physical therapy, the range of motion of the knee, and the need for physical support were assessed as well. Adverse events and vital signs were recorded. Results: Of 168 patients randomized to receive the 20-mg injection of DepoDur, the 30-mg injection of DepoDur, or the sham epidural injection, fifty-one, fifty-eight, and fifty-five patients, respectively, were included in the efficacy analysis. Compared with the patients treated with intravenous patient-controlled analgesia with morphine, the patients treated with DepoDur had significantly reduced mean pain-intensity-recall scores during the four to eight, four to twelve, four to twenty-four, and four to thirty-hour postdose intervals (p < 0.05 for all comparisons). The patients treated with DepoDur used approximately a threefold lower amount of postoperative opioids in total, with a significant percentage requiring no supplemental opioids. Adverse events common to all groups were nausea (78%), pyrexia (46%), vomiting (43%), pruritus (43%), and hypotension (36%). Respiratory depression was the most common serious adverse event, with serious respiratory depression observed in four DepoDur-treated patients, who were more than sixty-five years of age. Conclusions: With appropriate patient selection and monitoring, perioperative single-dose epidural DepoDur was a safe and effective analgesic alternative to postoperative intravenous patient-controlled analgesia following knee arthroplasty, with younger patients benefiting from the 20-mg dose. Additional studies of 10 to 15-mg doses for older patients are warranted. Level of Evidence: Therapeutic Level I. See Instructions to Authors for a complete description of levels of evidence.

The persisting analgesic effect of low-dose intravenous ketamine after spinal anaesthesia for Caesarean section

To compare the analgesic effects of intrathecal fentanyl and low-dose intravenous ketamine as adjuvants to intrathecal bupivacaine for Caesarean section. Ninety elective Caesarean section patients were randomized into three groups. Spinal anaesthesia was performed with 15 mg hyperbaric bupivacaine in all groups. Ketamine (0.15 mg kg(-1)) or an equal volume of normal saline was given intravenously immediately after initiating spinal anaesthesia in the ketamine and control group, respectively. In the fentanyl group, 10 microg fentanyl was added to the intrathecal bupivacaine. Arterial pressures, heart rate values, adverse effects, the time of first request for postoperative analgesia, visual analogue pain scores, total analgesic consumptions at 24 and 48 h were recorded in all patients. The time to first request for analgesia was significantly longer in the ketamine (197 min) and fentanyl (165 min) groups compared to the control group (144 min). Postoperative pain scores were significantly lower in the ketamine group than in both other groups. Although the analgesic requirements during first 24 h were significantly lower in the ketamine group, there was no significant difference between the groups during the following 24 h. Intravenous low-dose ketamine combined with intrathecal bupivacaine for Caesarean section provides longer postoperative analgesia and lower postoperative analgesic consumption than bupivacaine alone suggesting a pre-emptive effect.

Double‐blind comparison of ropivacaine 7.5 mg mL−1 for sciatic nerve block. (Ninewells Hospital and Medical School, Dundee, United Kingdom) British J Anesh. 2001;26:209–214.

Two groups of 12 patients had a sciatic nerve block performed with 20 mL of either ropivacaine 7.5 mg mL−1 or bupivacaine 5 mg mL−1. There was no statistically significant difference in the mean time to onset of complete anesthesia of the foot or to the first request for postoperative analgesia. The quality of the block was the same in each group. Although there is no statistically significant difference in the mean time to peak plasma concentrations the mean peak concentration of ropivacaine was significantly higher than that of bupivacaine. There were no signs of systemic local anesthetic toxicity in any patient in either group.

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 performed with 20 ml of either ropivacaine 7.5 mg ml(-1) or bupivacaine 5 mg ml(-1). There was no statistically significant difference in the mean time to onset of complete anaesthesia of the foot or to first request for post-operative analgesia. The quality of the block was the same in each group. Although there was no statistically significant difference in the mean time to peak plasma concentrations the mean peak concentration of ropivacaine was significantly higher than that of bupivacaine. There were no signs of systemic local anaesthetic toxicity in any patient in either group.

Intrathecal morphine for postoperative analgesia following repair of frontal encephaloceles in children: Comparison with intermittent, on-demand dosing of nalbuphine

Study Objective: To determine the efficacy of lumbar intrathecal (IT) morphine in a dose of 0.02 mg/kg in providing analgesia following repair of frontal encephaloceles. Design: Prospective, open-label investigation of IT morphine with secondary comparison to a retrospective cohort. Setting: Metropolitan hospital in the Philippines. Patients: 24 ASA physical status I and II children undergoing frontal encephalocele repair. Interventions: Following induction of general anesthesia, IT morphine (Group 1) was administered via single-shot technique or through a lumbar IT drain placed for cerebrospinal fluid drainage during the surgical procedure. Postoperative analgesia was assessed by visual analog score in patients greater than 5 years of age or a behavioral score in patients less than 5 years of age. The retrospective cohort received postoperative analgesia with intermittent doses of intravenous nalbuphine (Group 2). Measurements and Main Results: Group 1 had decreased postoperative analgesic requirements, decreased intraoperative inhalational anesthetic requirements, and a longer time to the first request for postoperative analgesia than Group 2. The time to the first request for postoperative analgesia was 16.0 ± 9.1 hours in Group 1 and 1.6 ± 1.2 hours in Group 2 ( p < 0.0001). Six of 12 patients in Group 1 required no analgesic drugs during the first 24 postoperative hours while all 12 patients in Group 2 ( p = 0.02) did require analgesic drugs during this period. The patients in Group 1 who did not require supplemental analgesic drugs maintained pain scores of 2 or less throughout the first 24 postoperative hours. Conclusion: Lumbar IT morphine provides effective analgesia following repair of frontal encephaloceles in children and adolescents.