Onset Of Sensory Analgesia Research Articles

Comparative Study of Dexmedetomidine versus Fentanyl as an adjuvant to Ropivacaine (0.75%) in Epidural Anaesthesia in Lower Limb Orthopaedic Surgery

Background: Dexmedetomidine and Fentanyl both possess hypnotic, sedative, analgesic properties and have been utilised as an additive in epidural anaesthesia. The purpose of this study is to compare the sedative and analgesic effects of Dexmedetomidine and Fentanyl when added epidurally with Ropivacaine (0.75%) during lower limb orthopaedic surgery.
 Methods: The study comprised of 60 patients, both male and female, aged 18 to 60, who had ASA classification I or II for tibia fibula surgery. Two groups of patients were split up at random: Group RD contains– Ropivacaine (0.75%) 15ml + Dexmedetomidine (1microgm/kg) 0.5ml + 0.5ml sterile water (Total volume-16ml) and Group RF - Ropivacaine 15ml (0.75%) + 1ml Fentanyl (1microgm/kg) (Total volume-16 ml). The epidural space was maintained 4 cm within and situated between L3 and L4 space. Investigations were conducted on parameters such as sensory and motor block features, sedation score, hemodynamic factors and pain assessment. Using the student `t` test, statistical analysis was performed using STATAIC13 software.
 Results: Onset of sensory analgesia at L1 and Complete sensory and motor blockage occurred much earlier in the RD group. Higher sedation scores and significantly prolonged postoperative analgesia was observed in RD group.
 Conclusion: Dexmedetomidine is a safer and more effective epidural adjuvant than fentanyl because it provides stable hemodynamics, extended post-operative analgesia, early onset and development of sensory and motor effects and sedation.

Comparative study of dexmedetomidine and fentanyl as an adjuvant to bupivacaine for epidural Anaesthesia in lower limb Orthopedic surgeries

Background: The addition of adjuvants to local anaesthetics causes an improvement in the quality and duration of analgesia which is a pivotal component for both intra operative and post-operative haemodynamic stability. Our study aims to compare the effect of Dexmedetomidine and fentanyl as an adjuvant to epidural bupivacaine in lower limb orthopedic surgeries. Methods: 60 patients of ASA grade l and ll were randomized into two groups: Gr BD: received 15 ml of 0.75% bupivacaine with 1µg/kg dexmedetomidine and Gr BF: received 15 ml of 0.75% bupivacaine with 1µg/kg fentanyl. Onset of sensory analgesia using cold swab or pinprick, onset of motor blockade using Bromage scale, intra operative hemodynamic variations and complications, time of first demand for analgesia, sedation using Ramsay sedation scale were studied. Results: The onset (BD-8.75 ± 2.0, BF-10.85 ± 1.8) and duration of sensory blockade (BD-335 ± 31.5, BF-268 ± 36) was found to be better in BD group, incidences of sedation and hypotention were found to be more in the dexmedetomidine group. Conclusion: Dexmedetomidine as an adjuvant in a dose of 1 µg/kg is an effective adjuvant to bupivacaine for epidural anesthesia, as compared to fentanyl.

Effects of intrathecal midazolam-bupivacaine combination on postoperative analgesia

Background and aim Subarachnoid injection of local anesthetic with midazolam potentiates spinal blockade. Midazolam is known to produce antinociception and to potentiate the effect of local anesthetic when given in the neuraxial block without significant side effects. This study was designed to assess the effects of adding midazolam to intrathecal bupivacaine in patients undergoing subumbilical surgery. Patients and methods Sixty adult patients were randomly divided into two groups: Group I was administered 3 ml of 0.5% hyperbaric bupivacaine+0.4 ml of normal saline and Group II was administered 3 ml of 0.5% hyperbaric bupivacaine+2 mg (0.4 ml) of preservative-free midazolam. Time of onset of sensory analgesia, level of sensory blockade, time for maximum cephalic spread, and motor blockade as well as vital parameters and intraoperative complications were assessed and recorded. Postoperative pain scores were assessed using the visual analog scale immediately postoperatively. Results The level of sensory blockade is higher in group II while the time of maximum cephalic spread was longer in group I. Concerning the postoperative visual analog scale, there were lower scores in group II than in group I. There was significant difference between groups I and II regarding total diclofenac sodium consumption in the postoperative 24 h with total consumption of 146.83±53.25 and 112.33±25.18 mg, respectively. The P value was found to be 0.002. Conclusion Subarachnoid injection of preservative-free midazolam as an adjuvant to intrathecal bupivacaine potentiates its effect in terms of prolonged motor and sensory blockade without any significant hemodynamic compromise or sedation and with a significant decrease of postoperative analgesic requirements.

The comparative study of two techniques of lumbar plexus block by anterior and posterior approach for lower limb surgery

Background: Lower extremity peripheral nerve blocks (PNBs) have been traditionally less employed compared to other forms of regional anesthesia. The advent of peripheral nerve stimulator and ultrasonography, complications associated with neuraxial anesthesia, and improved rehabilitation with PNBs has led to renewed interest in lower limb blocks. Lumbar plexus block can be given by anterior (Winnie's “3 in 1” block) and posterior (psoas compartment block) approaches. Subjects and Methods: In this randomized, observer-blinded study, we compared these techniques in two groups of patients (Group A [n = 30] and Group P [n = 30]) undergoing lower limb surgeries using nerve locator. They were supplemented with sciatic nerve block by Labat's approach. The primary objective was to compare the onset of sensory and motor blockade. Secondary objectives included the duration of sensory and motor blockade, sparing of nerves and complications if any. The onset of sensory analgesia was assessed by visual analog scale

Study of Efficacy of Tramadol as an Adjuvant to Lignocaine in Intravenous Regional Anesthesia at a Tertiary Care Teaching Centre

Introduction: Tramadol is a central analgesic with an opioid agonistic activity with some selectivity for µ-receptors. Several studies showed that tramadol is beneficial as an additive to local anesthetics in different regional nerve blocks including infiltration, caudal block, brachial plexus block and IVRA. However, the existing data on its role as an additive for IVRA are conflicting. Therefore, a prospective, randomized controlled trial was conducted to determine efficacy of Tramadol (100mg) as an intra-operative, post-operative and pre-emptive analgesic as an adjuvant to lignocaine in IVRA. Materials and Methods: Present study was carried out in 80 patients undergoing upper arm orthopedic surgery at Sharda Hospital, School of Medical Sciences and Research, Sharda University, Greater Noida, Uttar Pradesh, India. All patients selected were planned for forearm surgeries, of ASA Grade I or II, aged 16-60 years. Patients received 0.5% lignocaine 40 ml in one group and we added Tramadol 100 mg in the other group. All the patients were monitored for onset of effect, quality of anesthesia, post op analgesia after deflation of tourniquet, time of first analgesic drug and number of analgesic drug required in first 24 hrs. Results: Onset of sensory analgesia was significantly earlier in group B (59.7±23.8 sec v/s 196.3±42.7) while onset of motor paralysis was similar in both groups. The post-operative analgesia was significantly longer in group B (304.7 ± 87.9 mins) then group A (12.6 ± 5.1 mins). Accordingly the number of analgesics consumed in post-operative first 24 hours was significantly less in group B (1.2±0.6) then group A (2.9±0.8). Conclusion: Tramadol has favorable effects as an adjuvant to lignocaine for IVRA. Tramadol substantially shortens the onset of sensory block, improves patient’s tolerance of tourniquet, prolongs the duration of analgesia after deflation of tourniquet and reduces the postoperative analgesic consumption.

Comparative study of the effect of dexmedetomidine and butorphanol as epidural adjuvants in abdominal hysterectomy under intrathecal levobupivacaine anesthesia

Background: Combined spinal-epidural technique has become increasingly popular in the last few years for abdominal hysterectomies. Opioids or α-2 agonists are being increasingly used as epidural adjuncts. Aims: The aim of this study is to compare the clinical profile of dexmedetomidine and butorphanol when administered epidurally, following intrathecal levobupivacaine (heavy) in combined spinal and epidural anesthesia. Materials and Methods: Sixty adult patients aged 18-60 years, the American Society of Anesthesiologists Physical Status I and II undergoing abdominal hysterectomy were enrolled into the study and randomly divided into two groups: Group LD ( n = 30) received 12.5 mg of 0.5% levobupivacaine (heavy) intrathecally plus dexmedetomidine 1 ΅g/kg in 10 ml saline epidurally and Group LB ( n = 30) received 12.5 mg of 0.5% levobupivacaine (heavy) intrathecally plus butorphanol 10 ΅g/kg in 10 ml saline epidurally. The hemodynamics, block characteristics, and side effects were observed; the data were compiled and analyzed using Student's t -test and Chi-square test. P Results: The demographic profiles of the patients were comparable between the two groups. The onset of sensory analgesia at T10 was significantly faster in the Group LD (92.80 ± 31.51 vs. 105.43 ± 42.04 s). The time to two-segmental regression in dexmedetomidine group was 184.23 ± 45.10 min versus 120.40 ± 33.03 min in butorphanol group ( P P P Conclusions: Dexmedetomidine was a better alternative to butorphanol as an epidural adjuvant providing comparable stable hemodynamics, early onset, and establishment of sensory anesthesia, prolonged postoperative analgesia, and much better sedation.

Comparison of dexmedetomidine and clonidine as an adjuvant to ropivacaine for epidural anesthesia in lower abdominal and lower limb surgeries.

Background:The quality and duration of analgesia is improved when a local anesthetic is combined with alpha 2 adrenergic agonist. Though, the effects of clonidine on local anesthetics have been extensively studied, there are limited studies demonstrating the effects of epidural dexmedetomidine on local anesthetics. The aim of our study is to compare the effect of clonidine and dexmedetomidine when used as an adjuvant to epidural ropivacaine in lower abdominal and lower limb surgeries.Materials and Methods:Patients were randomized into two groups-group ropivacaine with clonidine (RC) received 15 ml of 0.75% ropivacaine with 1 μg/kg clonidine and group ropivacaine with dexmedetomidine (RD) received 15 ml of 0.75% ropivacaine with 1 μg/kg dexmedetomidine epidurally. Onset of sensory analgesia using cold swab, onset of motor blockade using Bromage scale, time to 2 dermatome regression of sensory level, time to first demand for analgesia, sedation using Ramsay sedation scale, intra operative hemodynamic parameters and complications were assessed.Results:The onset (RD-8.53 ± 1.81, RC-11.93 ± 1.96) and duration of sensory blockade (RD-316 ± 31.5, RC-281 ± 37, sedation were found to be significantly better in the dexmedetomidine group. No significant difference was found in terms of onset of motor blockade and hemodynamic changes.Conclusion:Dexmedetomidine at doses of 1 μg/kg is an effective adjuvant to ropivacaine for epidural anesthesia, which is comparable to clonidine.

Ultrasound guided single injection caudal epidural anesthesia of isobaric bupivacaine with/without dexamethasone for geriatric patients undergoing total hip replacement surgery

BackgroundDexamethasone has anti-inflammatory properties that can affect postoperative analgesia when added to caudal bupivacaine.MethodsSeventy-two geriatric patients scheduled for elective total hip replacement under ultrasound guided caudal anesthesia were randomized blindly into two groups: Group BD received caudal isobaric bupivacaine 0.25% (20 ml) and dexamethasone 8 mg (2 ml) and Group BS received caudal isobaric bupivacaine 0.25% (20 ml) and normal saline (2 ml). Postoperative analgesia was assessed by recording time to first rescue analgesia and the analgesic doses (paracetamol and meperidine hydrochloride) required during the first 24 h postoperatively as a primary outcome. Secondary outcomes were the time taken to the onset of sensory analgesia at T10, time to the onset of complete motor block, VAS pain score at rest and on movement at 1, 2, 4, 6, 8, 12 and 24 h, and postoperative adverse events.ResultsGroup BD had a significantly longer time to first rescue analgesia [402 (63) vs 213 (53)] min and significantly lower doses of paracetamol [3389 (728) vs 2833 (697)] mg meperidine hydrochloride [78 (30) vs 142 (28)] mg than Group BS. VAS scores were significantly lower in Group BD than Group BS both at rest and on movement respectively at 4, 6, 8, 12 and 24 h.ConclusionAdding dexamethasone with isobaric bupivacaine caudal anesthesia prolongs the duration of postoperative analgesia and decreased postoperative analgesic requirement in geriatric patients undergoing total hip replacement surgery in comparison isobaric bupivacaine alone.

The influence of epidural dexmedetomidine and clonidine on ropivacaine epidural anesthesia

Objective The aim of this study was to evaluate the efficacy of epidural dexmedetomidine (Dex) and clonidine on ropivacaine epidural anesthesia.Methods Seventy-five patients ASA Ⅰ or Ⅱ,aged 55 y-65 y,scheduled for elective vaginal hysterectomy under epidural anesthesia with ropivacaine were randomly allocated into three groups:patients in group RD were administered 15 ml of 0.75％ epidural ropivacaine and 100 μg of Dex,while group RC received admixture of 15 ml of 0.75％ropivacaine and 100 μg of clonidine,and group C received 15 ml of 0.75％ ropivacaine and saline.Results The patient in group RD exhibited an earlier onset of sensory analgesia at T10 [(8.5±2.4) min] as compared to group RC and group C [(10.4±3.4) min and (12.7±4.3) min].Dex not only provided a higher dermatomal spread but also helped in achieving the maximum sensory anaesthetic level in a shorter period [(13±4) min compared to clonidine (15±4) min and (18±4) min].Bromage scale 3 was achieved earlier in group RD [(18±5) min] than in group RC and group C [(21±4) min and (24±4) min,P＜0.05].Less tramadol consumed in group RD [(87±17) mg] than that in group RC and in group C [(101±21) min and (146±19) mg,P＜0.01] for postoperative analgesia of 24 h(P＜0.05).Sedation scores in group RD and group RC were better than in group C(P＜0.05).The incidence of shivering was lower in group RD and group RC than that in group C (P＜0.05).Respiratory depression was not observed in each group.Conclusions Epidural Dex may reinforce the effect of epidural anaesthesia with ropivacaine and analgesia.Dex is a better neuraxial adjuvant compared to clonidine for providing early onset of sensory analgesia,stable cardio-respiratory parameters and a prolonged post-operative analgesia. Key words: Dexmedetomidine; Clonidine; Epidural anaesthesia; Ropivacaine

The effect of addition of intrathecal midazolam 1.5 mg to bupivacaine in patients undergoing abdominal hysterectomy

In this prospective, randomized, double blind placebo controlled study, we investigated the postoperative analgesic efficacy of 1.5mg of intrathecal midazolam as an adjunct to bupivacaine for spinal anaesthesia in 100 patients undergoing abdominal hysterectomy. Patients were allocated randomly to 2 groups: Group B received intrathecal 3.5 ml of 0.5% heavy bupivacaine plus 0.3 ml of 0.9% saline; Group BM received 3.5 ml of 0.5% heavy bupivacaine plus 1.5 mg of preservative free midazolam (5 mg/ml). Onset of sensory analgesia, maximum level of sensory block, time to reach it, and time to two segment regression were similar between the two groups (p > 0.05). Blood pressure and heart rate were comparable between groups. The mean duration of postoperative analgesia was less in group B compared with group BM. Supplemental analgesic dose requirement with pentazocine was significantly less in Group BM compared with Group B. No neurological deficits were observed. Intraoperative sedation and oxygen desaturation was significantly higher but acceptable in Group BM. Conclusion: Intrathecal midazolam 1.5 mg when used as an adjunct to bupivacaine provides better intraoperative sedation and moderate prolongation of postoperative analgesia. DOI: http://dx.doi.org/10.4038/slja.v19i2.2314 Sri Lankan Journal of Anaesthesiology Vol.19(2) 2011 pp.81-85

Neuraxial opioids in geriatrics: A dose reduction study of local anesthetic with addition of sufentanil in lower limb surgery for elderly patients

Background and Objectives:Neuraxial anesthesia in the elderly is associated with exaggerated responses to conventional doses of local anesthetics, thereby increasing the incidence of hemodynamic complications. A double-blind prospective study was carried out in our institute with an aim to compare the hemodynamic stability and quality of the conventional dose of hyperbaric bupivacaine (LA) with low dose of LA and sufentanil in elderly patients scheduled for lower limb surgery, randomized to receive combined spinal epidural anesthesia.Methods:A total of 50 elderly patients of ASA grade I and II, divided randomly into groups I and II, of either sex undergoing lower limb surgery under combined spinal epidural anesthesia at our institute attached to a Government Medical College were enrolled for study. Group I received 2.5 ml of intrathecal hyperbaric bupivacaine (LA), while group II received 1.5 ml of intrathecal LA+0.1 ml sufentanil (5 μg). Both initial and postoperative subarachnoid block characteristics, hemodynamic and respiratory parameters, duration of analgesia, and side effects were observed and recorded. Statistical analysis was carried out using Chi-square and paired t test.Results:Demographic profile was comparable in both groups. Group I had a greater incidence of hypotension and, consequently, higher use of vasopressors (P<0.05). Onset of sensory analgesia, time to achieve peak sensory level, and recovery from motor blockade were significantly earlier in group II (P<0.05). Postoperative consumption of LA through epidural route was significantly higher in group I (P<0.05). The side effect profile was similar, except for a significantly higher incidence of shivering in group I (P<0.05).Conclusions:The study established that the dose of a local anesthetic can be safely and significantly lowered by 40%, with addition of low-dose sufentanil, thereby avoiding the hemodynamic fluctuation and providing a stable perioperative and postoperative period in the geriatric population. In addition, duration of sensory analgesia is prolonged and postoperative requirement for the epidural top-up also decreases.

Comparative evaluation of dexmedetomidine and fentanyl for epidural analgesia in lower limb orthopedic surgeries

Background and Aims:Opioids as epidural adjunct to local anesthetics (LA) have been in use since long and α-2 agonists are being increasingly used for similar purpose. The present study aims at comparing the hemodynamic, sedative, and analgesia potentiating effects of epidurally administered fentanyl and dexmedetomidine when combined with ropivacaine.Methods:A total of one hundred patients of both gender aged 21-56 years, American Society of Anaesthesiologist (ASA) physical status I and II who underwent lower limb orthopedic surgery were enrolled into the present study. Patients were randomly divided into two groups: Ropivacaine + Dexmedetomidine (RD) and Ropivacaine + Fentanyl (RF), comprising 50 patie nts each. Inj. Ropivacaine, 15 ml of 0.75%, was administered epidurally in both the groups with addition of 1 μg/kg of dexmedetomidine in RD group and 1 μg/kg of fentanyl in RF group. Besides cardio-respiratory parameters and sedation scores, various block characteristics were also observed which included time to onset of analgesia at T10, maximum sensory analgesic level, time to complete motor blockade, time to two segmental dermatomal regressions, and time to first rescue analgesic. At the end of study, data was compiled systematically and analyzed using ANOVA with post-hoc significance, Chi-square test and Fisher's exact test. Value of P<0.05 is considered significant and P<0.001 as highly significant.Results:The demographic profile of patients was comparable in both the groups. Onset of sensory analgesia at T10 (7.12±2.44 vs 9.14±2.94) and establishment of complete motor blockade (18.16±4.52 vs 22.98±4.78) was significantly earlier in the RD group. Postoperative analgesia was prolonged significantly in the RD group (366.62±24.42) and consequently low dose consumption of local anaesthetic LA (76.82±14.28 vs 104.35±18.96) during epidural top-ups postoperatively. Sedation scores were much better in the RD group and highly significant on statistical comparison (P<0.001). Incidence of nausea and vomiting was significantly high in the RF group (26% and 12%), while incidence of dry mouth was significantly higher in the RD group (14%) (P<0.05).Conclusions:Dexmedetomidine seems to be a better alternative to fentanyl as an epidural adjuvant as it provides comparable stable hemodynamics, early onset, and establishment of sensory anesthesia, prolonged post-op analgesia, lower consumption of post-op LA for epidural analgesia, and much better sedation levels.