Addition of dexmedetomidine to ropivacaine improves cervical plexus block

Clinical effects of perineural dexmedetomidine or magnesium sulphate as adjuvants to ropivacaine in dogs undergoing tibial plateau leveling osteotomy

The study aimed to compare the quality of perioperative analgesia, the motor block duration, and the effects on main cardiovascular parameters of dexmedetomidine (1 μg/kg/nerve block) or magnesium sulphate (2 mg/kg/nerve block) as adjuvants to 0.3% ropivacaine for sciatic and saphenous nerves block in dogs undergoing tibial plateau leveling osteotomy (TPLO). Dogs randomly received perineural dexmedetomidine-ropivacaine (D group), magnesium sulphate-ropivacaine (M group), or ropivacaine (C group). Fentanyl was administered in case of intraoperative nociception. Postoperative pain was assessed using the Short Form-Glasgow Composite Measure Pain Scale (SF-GCMPS) and VAS scale. The duration of motor blockade and intra- and postoperative cardiovascular parameters were also recorded. Group M required significantly more fentanyl than D group (p = 0.04). Group M had a significantly higher SF-GCMPS score than group C at 4 (p = 0.002) and 5 h after extubation (p = 0.01), and a significantly higher VAS score than group D at 3 h after extubation (p = 0.03), and at 4 h if compared to group C (p = 0.009). No significant differences regarding the duration of motor blockade were detected between groups (p = 0.07). The heart rate was significantly lower in group D than in M and C groups intraoperatively and during the first 1.5 h post extubation. The addition of dexmedetomidine or magnesium sulphate as adjuvants to perineural ropivacaine did not improve the quality of perioperative analgesia and did not prolong the motor blockade in dogs undergoing sciatic and saphenous nerves block for TPLO surgery.

Comparative Study of Ropivacaine and Ropivacaine With Dexmedetomidine in Transversus Abdominis Plane (TAP) Block for Post-operative Analgesia in Patients Undergoing Cesarean Sections

Background Adequate post-operative analgesia in the obstetric patient is necessary to facilitate breastfeeding and the care of the newborn. Considering the limitations of intravenous analgesic options such as non-steroidal anti-inflammatory drugs (NSAIDs) and opioids, other alternatives have been tried for offering better analgesia with fewer potential side effects. Transversus abdominis plane (TAP) block is one such option that has been tried with various local anesthetic drugs, either alone or in combination with other adjuvants. The addition of dexmedetomidine to bupivacaine in TAP block has been shown to prolong the duration of post-operative analgesia when compared to local anesthetic alone. This study was conducted to determine the efficacy of dexmedetomidine, as an adjuvant to ropivacaine, when administered in TAP block in patients undergoing cesarean section. Methodology The study was a prospective, randomized, parallel assignment, triple-blinded controlled trial. Hundred patients posted for elective lower segment cesarean section, fulfilling the inclusion criteria, were randomly divided into two equal groups, group R and group RD, comprising 50 patients each. Patients in group R were administered bilateral TAP block by landmark technique using ropivacaine alone, whereas patients in group RD were administered TAP block with dexmedetomidine 1 micrograms/kg, in addition to a similar dose of ropivacaine. Mean arterial pressure (MAP), heart rate (HR), visual analog scale (VAS)-R (pain score on VAS scale at rest), VAS-C (pain score on VAS scale on coughing), nausea and vomiting, and Ramsay sedation score were recorded on admission to post-operative care unit (PACU), and at first, fourth, eighth, 12th, 18th, and 24th hours post-operatively. Rescue analgesia was provided with intravenous morphine. Short Assessment of Patient Satisfaction Score (SAPS) was noted on a five-point scale after 24 hours based on patient satisfaction regarding the quality of post-operative analgesia. Results While there was no significant difference between groups R and RD with respect to VAS-C and VAS-R immediately after shifting and at the first, fourth, and eighth hours, a significant difference was observed at the 12th and 18th hours post-operatively. After 24 hours, no significant difference was observed between groups R and RD with respect to VAS-C and VAS-R. While 50% of patients needed rescue analgesia in group R, only 28% of patients needed rescue analgesia in group RD. There was significantly better patient satisfaction measured by the Short Assessment of Patient Satisfaction Score (SAPS) with respect to the quality of analgesia in patients in group RD as compared to those in group R. Conclusions The addition of dexmedetomidine to ropivacaine increased the duration of post-operative analgesia up to 18 hours post-operatively in cases of elective lower segment cesarean section. Also, the quality of post-operative analgesia is better in such patients, as shown by a significant difference in patient satisfaction scores between the two groups.

Effect of dexmedetomidine added to retrobulbar blockade with lignocaine and bupivacaine in dogs undergoing enucleation surgery

OBJECTIVE

To investigate the effect of the addition of dexmedetomidine (BLD) to retrobulbar blockade with combined lignocaine and bupivacaine on nociception.

ANIMALS

A total of 17 eyes from 15 dogs.

METHODS

Prospective, randomized, masked clinical comparison study. Dogs undergoing unilateral enucleation were randomly assigned into two groups; a retrobulbar administration of lignocaine and bupivacaine in a 1:2 volume ratio combined with either BLD or 0.9% saline (BLS). The total volume of the intraconal injection was calculated at 0.1 mL/cm cranial length. Intraoperative parameters were recorded: heart rate (HR), respiratory rate (RR), end-tidal CO2 (EtCO2 ) arterial blood pressure (BP), and inspired isoflurane concentration (ISOinsp). Pain scores, heart rate and RR were recorded postoperatively.

RESULTS

Dogs receiving BLD (n = 8) had significantly lower intraoperative RR (p = 0.007), and significantly lower ISOinsp (p = 0.037) than dogs in the BLS group (n = 9). Postoperatively heart rate was significantly lower in the BLD group at 1 min (p = 0.025) and 1 h (p = 0.022). There were no other significant differences in intraoperative or postoperative parameters, or in postoperative pain scores (p = 0.354). Dogs receiving BLD had a higher rate of anesthetic events of bradycardia and hypertension (p = 0.027). Analgesic rescue was not needed in either group.

CONCLUSIONS

The addition of BLD to retrobulbar anesthesia did not result in a detectable difference in pain scores relative to blockade with lignocaine and bupivacaine alone. Dogs receiving retrobulbar BLD had a significantly lower intraoperative RR and isoflurane requirement and an increased incidence of intraoperative bradycardia and hypertension.

Transversus abdominis plane block versus caudal block with bupivacaine and dexmedetomidine for unilateral inguinal hernia repair in pediatric patients: a randomized clinical trial

BACKGROUND

This study compared the transversus abdominis plane (TAP) block with bupivacaine and dexmedetomidine to the same mixture in the caudal block in delivering postoperative analgesia in children after unilateral inguinal hernia surgery.

METHODS

The current study included 80 children aged two to eight years who were scheduled for unilateral inguinal hernia surgery under general anesthesia. A caudal block (1 mL/kg 0.25% bupivacaine and one µg /kg dexmedetomidine) or a TAP block (1 mL/kg 0.25% bupivacaine and one µg /kg dexmedetomidine) was given to each participant at random. The time it took to request analgesia for the first time, the postoperative pain score, total analgesic use, sedation, family satisfaction, and side effects were all measured. The primary outcome was time to first analgesic request.

RESULTS

The caudal block group had a considerably shorter time to first analgesic request than the TAP block group. The caudal block group received more rescue analgesia doses within 24 hours than the TAP block group. The mean total dose of intravenous paracetamol within the first 24 hours postoperatively was greater in the caudal block group. The caudal block group had much higher family satisfaction.

CONCLUSIONS

The TAP block and caudal block provide good postoperative analgesia in children undergoing unilateral inguinal hernia repair. Adding dexmedetomidine to the TAP block was superior to the caudal block in terms of extending the length of the initial analgesic request, lowering analgesic requirement, and lowering pain scores without causing substantial adverse effects.

Effect of erector spinae plane block with different doses of dexmedetomidine as adjuvant for ropivacaine on the postoperative quality of recovery after video-assisted thoracoscopic lobectomy surgery: a randomized controlled trial

BACKGROUND

Erector spinae plane block (ESPB) improves postoperative analgesia and significantly enhances the quality of recovery (QoR) after video-assisted thoracoscopic lobectomy surgery (VATLS). However, it is not known whether the use of dexmedetomidine (Dex) as an adjunct for ropivacaine to ESPB affects the QoR after VATLS. The purpose of this study was to explore the effects of different Dex dosages as an adjunct for ropivacaine in combination with ultrasound-guided ESPB on the quality of postoperative recovery in patients with VATLS.

METHODS

In this single-center, double-blind, randomized study, 120 patients between the ages of 18 and 65 who were scheduled for VATLS from december 2021 and october 2022 in our hospital under general anesthesia were randomly divided into three groups: ultrasound-guided ESPB with 30 mL of 0.5% ropivacaine (Group R), ultrasound-guided ESPB 0.5% ropivacaine plus 0.5 µg/kg Dex (Group RD1), and ultrasound-guided ESPB 0.5% ropivacaine plus 1.0 µg/kg Dex (Group RD2), ultrasound-guided ESPB was administrated at the T5 vertebral level before surgery. The primary outcome was the QoR-15 score 24 h after the surgery. The secondary outcomes included the QoR-15 scores at 12 h, 48 h, and 72 h after the operation, visual analogue scale (VAS) scores at 8 h, 12 h, 24 h, and 48 h after surgery, cumulative flurbiprofen consumption, postoperative nausea and vomiting (PONV), postoperative bradycardia, and hypotension.

RESULTS

The QoR-15 scores were higher in group RD2 than the R and RD1 groups on postoperative day 1 (P < 0.05), in addition, no significant difference was found in the QoR-15 scores between groups R and RD1 on postoperative day 1. The VAS scores were significantly lower in group RD2 than in groups RD1 and group R 12-24 h after surgery (P < 0.05). No significant differences were observed in the QoR-15 and VAS scores at 48 and 72 h after surgery between the three groups. The cumulative flurbiprofen consumption was markedly reduced during the 72 h after surgery in the RD2 group (P < 0.05). The incidence of postoperative nausea and vomiting was lower in the RD2 group (P < 0.05).

CONCLUSIONS

The combination of 1 µg/kg dexmedetomidine as an adjunct with 0.5% ropivacaine 30 ml for erector spinae plane block significantly improved the postoperative quality of recovery and provided better postoperative analgesia on postoperative day 1 in patients undergoing Video-assisted thoracoscopic lobectomy surgery. However, dexmedetomidine (1 µg/kg) as an adjunct for ropivacaine combined with erector spinae plane block did not enhance the postoperative quality of recovery at 48 and 72 h postoperatively.

TRIAL REGISTRY NUMBER

The number of this clinical trial registry is ChiCTR2100053230, date of registration: 16/11/ 2021).

Dexmedetomidine as an Adjuvant in Peripheral Nerve Block

Peripheral nerve block technology is important to balanced anesthesia technology. It can effectively reduce opioid usage. It is the key to enhance clinical rehabilitation as an important part of the multimodal analgesia scheme. The emergence of ultrasound technology has accelerated peripheral nerve block technology development. It can directly observe the nerve shape, surrounding tissue, and diffusion path of drugs. It can also reduce the dosage of local anesthetics by improving positioning accuracy while enhancing the block's efficacy. Dexmedetomidine is a highly selective drug α₂-adrenergic receptor agonist. Dexmedetomidine has the characteristics of sedation, analgesia, anti-anxiety, inhibition of sympathetic activity, mild respiratory inhibition, and stable hemodynamics. Numerous studies have revealed that dexmedetomidine in peripheral nerve blocks can shorten the onset time of anesthesia and prolong the time of sensory and motor nerve blocks. Although dexmedetomidine was approved by the European Drug Administration for sedation and analgesia in 2017, it has not yet been approved by the US Food and Drug Administration (FDA). It is used as a non-label drug as an adjuvant. Therefore, the risk-benefit ratio must be evaluated when using these drugs as adjuvants. This review explains the pharmacology and mechanism of dexmedetomidine, the effect of dexmedetomidine on various peripheral nerve block as an adjuvant, and compare it with other types of adjuvants. We summarized and reviewed the application progress of dexmedetomidine as an adjuvant in nerve block and look forward to its future research direction.

Pelvic limb anesthesia and analgesia in dogs undergoing tibial plateau leveling osteotomy (TPLO): A survey of board-certified anesthesiologists

OBJECTIVE

To report the locoregional anesthesia and analgesia preferences of veterinary anesthesiologists for use in dogs undergoing a TPLO and determine any association with specialty college, time from board-certification, or employment sector.

STUDY DESIGN

Cross sectional study.

SAMPLE POPULATION

Diplomates of the American (ACVAA) and European (ECVAA) Colleges of Veterinary Anesthesia and Analgesia.

METHODS

An electronic survey was distributed to diplomates and responses were used to determine associations between preferred methods.

RESULTS

The survey response rate was 28% (141/500) with 69% (97/141) of ACVAA diplomates and 31% of diplomates with ECVAA (44/141) certification. Peripheral nerve block (PNB) was preferred by 79% (111/141) of all diplomates, lumbosacral epidural (LE) by 21% (29/141), and peri-incisional infiltration (PI) by <1% (1/141). There was no association (p = .283) with specialty college. There was an association (p < .001) with time from board-certification with increased preference for LE when >10-years from certification and PI preferred by only those board-certified >20-years ago. There was an association with employment sector (p = .003) with more academic diplomates preferring LE. Anesthesiologists reported that treatment decisions were affected by various factors including time pressure and surgeon influence.

CONCLUSION

Diplomates of ACVAA and ECVAA prefer PNB as the locoregional method of pelvic limb anesthesia in dogs undergoing TPLO. A greater percentage of newer and private practice diplomates prefer PNB while a larger percentage of senior and academic diplomates prefer LE. Decision making is multifactorial and includes perceived time pressure and surgeon influence.

CLINICAL SIGNIFICANCE

Veterinary anesthesiologists prefer and frequently use PNB in dogs undergoing TPLO and surgeon influence may affect their chosen treatment.

Comparison of the Analgesic Effects of Intravenous Infusion of Dexmedetomidine Versus Bilateral Superficial Cervical Plexus Block After Thyroidectomy: A Randomized Controlled Trial

OBJECTIVES

Dexmedetomidine (DEX) is widely used in clinical practice because of its safety and effectiveness. Superficial cervical plexus block (SCPB) can reduce pain in thyroid surgery. The objective of this study was to investigated whether intravenous DEX has an equivalent analgesic effect and patients' satisfaction to SCPB for thyroid surgery.

MATERIALS AND METHODS

Ninety patients who had been scheduled for thyroidectomy under general anesthesia with endotracheal intubation were randomly divided into 3 groups. Group D: DEX was administered intravenously at an initial dose of 1 µg/kg over 10 minutes; then induction and endotracheal intubation performed, and then a continuous intravenous infusion of DEX was administered at a rate of 0.4 μg/kg/h until 30 minutes before the end of surgery. Group B: ultrasound-guided bilateral SCPB was performed, with 10 mL of 0.375% ropivacaine injected on each side. Group C: intravenous saline was administered at the same rate and dose as in group D. Patients' perioperative status, visual analog scale scores, complications and patients' satisfaction were recorded.

RESULTS

The pain at rest at 1 hour after extubation and the movement-evoked pain within 24 hours after extubation were significantly lower in groups D and B than in group C. Patients' satisfaction was significantly higher in groups D and B than in group C. There was no difference in pain at rest, movement-evoked pain and patients' satisfaction between group D and B.

CONCLUSIONS

Perioperative intravenous infusion of DEX can effectively reduce wound pain after thyroidectomy, and the analgesic effect is equivalent to that of bilateral SCPB.

Effects of perineural administration of ropivacaine combined with perineural or intravenous administration of dexmedetomidine for sciatic and saphenous nerve blocks in dogs

OBJECTIVE

To evaluate the effects of using ropivacaine combined with dexmedetomidine for sciatic and saphenous nerve blocks in dogs.

ANIMALS

7 healthy adult Beagles.

PROCEDURES

In phase 1, dogs received each of the following 3 treatments in random order: perineural sciatic and saphenous nerve injections of 0.5% ropivacaine (0.4 mL/kg) mixed with saline (0.9% NaCl) solution (0.04 mL/kg; DEX0PN), 0.5% ropivacaine mixed with dexmedetomidine (1 μg/kg; DEX1PN), and 0.5% ropivacaine mixed with dexmedetomidine (2 μg/kg; DEX2PN). In phase 2, dogs received perineural sciatic and saphenous nerve injections of 0.5% ropivacaine and an IV injection of diluted dexmedetomidine (1 μg/kg; DEX1IV). For perineural injections, the dose was divided equally between the 2 sites. Duration of sensory blockade was evaluated, and plasma dexmedetomidine concentrations were measured.

RESULTS

Duration of sensory blockade was significantly longer with DEX1PN and DEX2PN, compared with DEX0PN; DEX1IV did not prolong duration of sensory blockade, compared with DEX0PN. Peak plasma dexmedetomidine concentrations were reached after 15 minutes with DEX1PN (mean ± SD, 348 ± 200 pg/mL) and after 30 minutes DEX2PN (816 ± 607 pg/mL), and bioavailability was 54 ± 40% and 73 ± 43%, respectively. The highest plasma dexmedetomidine concentration was measured with DEX1IV (1,032 ± 415 pg/mL) 5 minutes after injection.

CONCLUSIONS AND CLINICAL RELEVANCE

Results suggested that perineural injection of 0.5% ropivacaine in combination with dexmedetomidine (1 μg/kg) for locoregional anesthesia in dogs seemed to balance the benefit of prolonging sensory nerve blockade while minimizing adverse effects.

The Effect of Ultrasound-Guided Erector Spinae Plane Block Combined with Dexmedetomidine on Postoperative Analgesia in Patients Undergoing Modified Radical Mastectomy: A Randomized Controlled Trial

Introduction

One of the most common malignancies in women worldwide is breast cancer. Erector spinae plane block (ESPB) can reduce pain after modified radical mastectomy for breast cancer. The duration of nerve block analgesia is limited if local anesthetic agents are used alone. The purpose of this study was to evaluate the effect of dexmedetomidine on postoperative analgesia during a single injection of local anesthetics.

Methods

In this double-blind, randomized study, 60 female American Society of Anesthesiologists (ASA) I–II patients undergoing modified radical mastectomy were randomized into two groups: ultrasound (US)-guided ESPB with 30 mL of 0.33% ropivacaine (group R) and US-guided ESPB with 30 mL of dexmedetomidine plus 0.33% ropivacaine (group DR). US-guided ESPB at the T3 vertebral level was performed preoperatively in all patients. The indicators were 1-, 6-, 12-, 24-, and 48-h visual analog scale (VAS) pain scores after surgery in the resting state and at 90-degree shoulder abduction. Other measures were a comparison of intraoperative sufentanil and remifentanil, postoperative nausea and vomiting (PONV), flurbiprofen consumption, the lengths of post-anesthesia care unit (PACU) stay and hospital stay, postoperative bradycardia, and hypotension.

Results

The VAS pain score was lower in group DR than group R at any time in the resting state, except at 1 h after surgery. The VAS pain score was lower in group DR than group R at 12 and 24 h in an active state after surgery (P < 0.05 for each time interval). The intraoperative dosages of remifentanil and sufentanil in group DR were lower than that in group R. The postoperative dosage of flurbiprofen in group DR was lower than that in group R (P = 0.038). The lengths of PACU stay were longer in group DR than in group R. No significant difference was found in PONV and hospital stay between the two groups. No sinus bradycardia or hypotension after surgery occurred in the two groups.

Conclusions

Dexmedetomidine as an adjunctive to ESPB can effectively relieve pain and significantly reduce the need for opioids during modified radical mastectomy for breast cancer.

Trial Registration

The study was registered in the Chinese Clinical Trial Registry (ChiCTR2000031134, principal investigator: Yao Lu, date of registration: 2020-3-22).

The effect of bupivacaine on postoperative pain following thyroidectomy: a systematic review and meta-analysis

INTRODUCTION

Thyroid surgery, which is usually followed by moderate postoperative pain, has gained increasing attention in recent years. A systematic review and meta-analysis was conducted to assess the effect of prophylactic bupivacaine on postoperative pain following thyroidectomy.

EVIDENCE ACQUISITION

We searched the PubMed, Web of Science, Embase, and Cochrane Library databases for specific keywords. RevMan 5.0 and Stata 12.0 software were used to perform meta-analyses. The endpoints were postoperative pain, rescue analgesic requirement, and postoperative nausea and vomiting (PONV) during the immediate 24 h postoperative period.

EVIDENCE SYNTHESIS

A total of 18 randomized controlled trials (RCTs) with 1308 patients were included in the meta-analysis. A significant reduction of pain according to the postoperative pain scale at 1 hour (P<0.05) and rescue analgesic requirement (P<0.05) was observed following local infiltration with bupivacaine. A bilateral superficial cervical plexus block (BSCPB) with bupivacaine also significantly reduced postoperative pain at 1 hour (P<0.01) and 24 hours (P<0.01), as well as rescue analgesic requirement (P<0.00001) and PONV (P<0.01). Compared with BSCPB, local infiltration with bupivacaine provides a better effect in terms of postoperative analgesia (P<0.05).

CONCLUSIONS

We recommend local infiltration with bupivacaine ranged from 20 to 75 mg before or after skin closure or BSCPB with bupivacaine ranged from 25 to 100 mg to reduce postoperative pain after thyroidectomy.

Dexmedetomidine combined with ropivacaine in ultrasound-guided tranversus abdominis plane block improves postoperative analgesia and recovery following laparoscopic colectomy

The present prospective, double blind, randomized clinical study was designed to evaluate whether dexmedetomidine (Dex) combined with ropivacaine for tranversus abdominis plane (TAP) block could improve analgesic quality and duration, and promote recovery following laparoscopic colectomy. Following induction of anesthesia, ultrasound-guided bilateral TAP block was performed in 60 patients scheduled for elective laparoscopic colectomy with either 20 ml of 0.375% ropivacaine plus 2 ml normal saline 0.9% (R group), or 20 ml of 0.375% ropivacaine plus 2 ml Dex (0.5 µg/kg) (RD group). Visual analogue scale (VAS) score for pain, sedation level, length of hospital stay (LOS), and bowel function recovery time and associated complications were recorded. Overall patient satisfaction with postoperative pain management was also assessed. The hemodynamic variables were not significantly different between the two groups during the surgery. However, the duration of analgesia was significantly longer in the RD group compared with the R group (P<0.05). VAS scores at 1, 2, 6 and 12 h following surgery were significantly decreased in the RD group compared with those in the R group (P<0.05). There was no significant difference in sedation level between the two groups. Notably, postoperative nausea and vomiting in the RD group was significantly decreased compared with those in the R group in the first 24 h (P<0.05). There were no serious adverse events in any group. Furthermore, 90.0 and 66.7% patients were satisfied with the postoperative pain management in the RD group and R group, respectively. The postoperative first bowel movement time was significantly shorter in the RD group compared with the R group (P<0.05). However, the LOS was not significantly different between the two groups. In conlusion, the addition of Dex to ropivacaine could significantly improve the analgesic quality and duration of TAP block, which in turn promotes recovery following laparoscopic colectomy.

Role of dexmedetomidine as adjuvant in postoperative sciatic popliteal and adductor canal analgesia in trauma patients: a randomized controlled trial

Background

The effect of dexmedetomidine as an adjuvant in the adductor canal block (ACB) and sciatic popliteal block (SPB) on the postoperative tramadol-sparing effect following spinal anesthesia has not been evaluated.

Methods

In this randomized, placebo-controlled study, ninety patients undergoing below knee trauma surgery were randomized to either the control group, using ropivacaine in the ACB + SPB; the block Dex group, using dexmedetomidine + ropivacaine in the ACB + SPB; or the systemic Dex group, using ropivacaine in the ACB + SPB + intravenous dexmedetomidine. The primary outcome was a comparison of postoperative cumulative tramadol patient-controlled analgesia (PCA) consumption at 48 hours. Secondary outcomes included time to first PCA bolus, pain score, neurological assessment, sedation score, and adverse effects at 0, 5, 10, 15, and 60 minutes, as well as 4, 6, 12, 18, 24, 30, 36, 42, and 48 hours after the block.

Results

The mean ± standard deviation of cumulative tramadol consumption at 48 hours was 64.83 ± 51.17 mg in the control group and 41.33 ± 38.57 mg in the block Dex group (P = 0.008), using Mann–Whitney U-test. Time to first tramadol PCA bolus was earlier in the control group versus the block Dex group (P = 0.04). Other secondary outcomes were comparable.

Conclusions

Postoperative tramadol consumption was reduced at 48 hours in patients receiving perineural or systemic dexmedetomidine with ACB and SPB in below knee trauma surgery.

Evaluation of analgesic efficacy of dexmedetomidine as adjuvant with ropivacaine in ultrasound-guided adductor canal block in patients following anterior cruciate ligament reconstruction surgeries

Introduction

Local anaesthetic (LA) with highly selective alpha-2 agonist dexmedetomidine has not been evaluated in adductor canal block (ACB) for arthroscopic anterior cruciate ligament (ACL) reconstruction surgeries. The study evaluates postoperative analgesic effect of ropivacaine with adjuvant dexmedetomidine following postoperative ultrasound-guided ACB.

Methods

105 randomized subjects received ultrasound-guided ACB using 15 mL of 0.5% ropivacaine, with 0.5 µg kg^-1 of dexmedetomidine administered perineurally (Group II), intravenously (Group III) or none (Group I). Primary outcome included 24 hours' total morphine consumption postoperatively. Secondary outcomes included haemodynamics and adverse effects.

Results

The postoperative total morphine consumption was significantly reduced till 4 hours in II 0.57 mg (0.98 (0-3)) (p = 0.011) and up to 6 hours in Group III 0.77 mg (1.00 (0-4)) (p = 0.004) compared to Group I. The postoperative total morphine consumption was comparable at 24 hours in Group III 3.57 mg (1.73 (0-8)) and Group II 3.34 mg (1.92 (07)) (p = 1.000). The visual analogue scale (VAS) scores were comparable in all the three groups at all the time intervals studied (p > 0.05). There were no adverse effects observed during the study.

Conclusion

Use of perineural dexmedetomidine with LA for ACB in the postoperative period resulted in significant reduction in total morphine consumption in initial 4 hours as compared to 6 hours with intravenous (IV) dexmedetomidine.

Effects of dexmedetomidine as an adjunct in transversus abdominis plane block during gynecological laparoscopy

Ultrasound-guided transversus abdominis plane (TAP) block for abdominal surgery has been widely studied in clinical settings. However, dexmedetomidine as an adjunctive analgesic combined with TAP block has been rarely reported. The present study evaluated the efficacy of TAP block combined with dexmedetomidine adjunct for gynecological laparoscopy. In brief, 90 patients were randomly divided into three groups: Group I, which received post-operative intravenous analgesia only after general anesthesia; Group II, which received a TAP block with 20 ml 0.375% ropivacaine; and Group III, which received a TAP block with 20 ml of 0.375% ropivacaine and 1 µg/kg dexmedetomidine after induction. In all groups, propofol was used for general anesthesia. The dosage of propofol, duration of the operation, and the time of awakening, spontaneous breathing and extubation were recorded. In addition, the Steward and visual analogue scale (VAS) scores were determined at 2, 4, 8, 12 and 24 h post-surgery. The occurrence of nausea and vomiting and/or respiratory depression was also recorded. Compared with those in Group I, the dosage of propofol, as well as the time of awakening, spontaneous breathing and extubation were significantly decreased in Group III (P<0.01 and P<0.05, respectively). In addition, the VAS score at 2 and 4 h in Group II (both P<0.05) and 2, 4 (both P<0.01) and 8 h (P<0.05) in Group III after the surgery were significantly lower compared with those in Group I. Furthermore, in Groups II and III, a lower number of cases experienced nausea and vomiting (P<0.05). In conclusion, the ultrasound-guided TAP block combined with dexmedetomidine adjunct may improve recovery from anesthesia and reduce post-operative pain (trial registration no. ChiCTR-IPR-15007398).

Dexmedetomidine as an Additive to Local Anesthesia: A Step to Development in Dentistry

PURPOSE

The study aimed to compare the effect of dexmedetomidine added to lidocaine against epinephrine added to lidocaine on local anesthetic potency and to look for future prospects of dexmedetomidine as an additive to local anesthesia in dentistry.

MATERIALS AND METHODS

The study included 25 healthy volunteers in whom extraction of all first premolars was scheduled as part of their orthodontic treatment plan. In this split-mouth, double-blind, crossover, randomized controlled trial, patients were randomized into 2 groups: Group 1 received injection lidocaine plus dexmedetomidine, and group 2 was administered lidocaine plus epinephrine. Patients were assessed for the onset of action of anesthesia, duration of analgesia, pain perception, and vital signs.

RESULTS

The mean values (±standard deviations) for the onset of anesthetic action in groups 1 and 2 were 113 ± 24.9 and 141 ± 34.8 seconds, respectively, for the mandible. For the maxilla, the mean values were 113 ± 24.9 seconds for group 1 and 165 ± 43.8 seconds for group 2. The duration of anesthesia was longer in group 1 (lidocaine plus dexmedetomidine), in which the requirement for the first analgesic on request was seen after a longer time interval, when compared with group 2 (lidocaine plus epinephrine). Pain perception elicited statistically significant results with less perception of pain in group 1 (lidocaine plus dexmedetomidine). The vital parameters remained stable, and the results were not statistically significant.

CONCLUSIONS

In this study, we observed that the addition of dexmedetomidine to lidocaine for maxillary and mandibular nerve blocks significantly prolonged the block duration and shortened the onset of action, as well as improved postoperative analgesia in terms of the need for fewer analgesics in the postoperative period. Furthermore, the vital parameters remained stable and no complications were encountered. The findings were supportive of the use of dexmedetomidine as an adjunct to local anesthetics in dental procedures.

Wound infiltration with bupivacaine 0.5% with or without adrenaline does not decrease pain after thyroidectomy. A randomized controlled study

Objectives:

To study the effect of local wound infiltration with and without adrenaline on pain perception after thyroidectomy using the visual analog score (VAS).

Methods:

A prospective randomized controlled double-blinded study was conducted between May 2015 and June 2016 at The University of Jordan Hospital, Amman, Jordan. Eighty-nine patients undergoing planned thyroidectomy were included in the study. Patients were divided randomly into 3 groups: Group A, local wound infiltration with bupivacaine 0.5% was administered; Group B, bupivacaine 0.5% with adrenaline was administered; Group C (control), no infiltration was performed. Standardized thyroidectomies were performed in the 3 groups. Pain perception was measured using VAS at 2, 4, 6, 12, and 24 hours after surgery. A comparison between the 3 groups was carried out.

Results:

No significant differences among the 3 groups were observed at all time points (p=0.246). Visual analog scores were significantly lower at 12 and 24 hours after operations.

Conclusion:

Local wound infiltration with bupivacaine 0.5% does not decrease pain perception after thyroidectomy performed under general anesthesia, and adding adrenaline does not enhance its effect.

Ultrasound-guided bilateral superficial cervical plexus block for thyroid surgery: The effect of dexmedetomidine addition to bupivacaine-epinephrine

Background:

The thyroid gland surgery is a common and painful procedure demanding analgesia. Many regional techniques are applied for anterior neck surgeries mostly assigned in relation to the involved cervical fascia. Dexmedetomidine (Precedex) is a selective alpha 2 adrenoceptor agonist which prolongs the sensory blockade duration of local anesthetics. Our study hypothesis is that ultrasound (US)-guided bilateral superficial cervical plexus block (BSCPB) may provide longer analgesia when adding dexmedetomidine to bupivacaine-epinephrine.

Purpose:

The aim of this study is to evaluate the analgesic efficacy and possible side effects of US-guided BSCPB and the effect of dexmedetomidine addition to bupivacaine-epinephrine in patients undergoing thyroid surgery.

Methods:

This prospective, double-blind, randomized study was performed on 42 patients randomized into two equal groups each of 21; bupivacaine Group B and dexmedetomidine Group D. Patients with contraindications to regional anesthesia or uncontrolled comorbidities were excluded from the study. Total pethidine consumption in 24 h is the primary outcome. The visual analog scale, timing of the first opioid request, and hemodynamics are the secondary outcomes.

Results:

In Group D, there was a longer time to the first request of opioid postoperatively, a lower total pethidine consumption and pain score postoperatively, and lower fentanyl requirements intraoperatively.

Conclusions:

Sonographic-guided bilateral SCPB using a combination of bupivacaine, dexmedetomidine, and epinephrine was superior to bupivacaine for prolonged analgesia with less intra- and postoperative opioid consumption and lower side effect profile during thyroid surgery.

Adjuvants to local anesthetics: Current understanding and future trends

Although beneficial in acute and chronic pain management, the use of local anaesthetics is limited by its duration of action and the dose dependent adverse effects on the cardiac and central nervous system. Adjuvants or additives are often used with local anaesthetics for its synergistic effect by prolonging the duration of sensory-motor block and limiting the cumulative dose requirement of local anaesthetics. The armamentarium of local anesthetic adjuvants have evolved over time from classical opioids to a wide array of drugs spanning several groups and varying mechanisms of action. A large array of opioids ranging from morphine, fentanyl and sufentanyl to hydromorphone, buprenorphine and tramadol has been used with varying success. However, their use has been limited by their adverse effect like respiratory depression, nausea, vomiting and pruritus, especially with its neuraxial use. Epinephrine potentiates the local anesthetics by its antinociceptive properties mediated by alpha-2 adrenoreceptor activation along with its vasoconstrictive properties limiting the systemic absorption of local anesthetics. Alpha 2 adrenoreceptor antagonists like clonidine and dexmedetomidine are one of the most widely used class of local anesthetic adjuvants. Other drugs like steroids (dexamethasone), anti-inflammatory agents (parecoxib and lornoxicam), midazolam, ketamine, magnesium sulfate and neostigmine have also been used with mixed success. The concern regarding the safety profile of these adjuvants is due to its potential neurotoxicity and neurological complications which necessitate further research in this direction. Current research is directed towards a search for agents and techniques which would prolong local anaesthetic action without its deleterious effects. This includes novel approaches like use of charged molecules to produce local anaesthetic action (tonicaine and n butyl tetracaine), new age delivery mechanisms for prolonged bioavailability (liposomal, microspheres and cyclodextrin systems) and further studies with other drugs (adenosine, neuromuscular blockers, dextrans).

Tramadol sparing effect of dexmedetomidine as an adjuvant with lignocaine in preoperative stellate ganglion block for postoperative pain relief following upper limb surgeries

Background

Recent literature has established the role of stellate ganglion block (SGB) for management of acute postoperative pain. The effects of dexmedetomidine as an adjuvant to lignocaine in a preoperative SGB for postoperative pain relief have not been evaluated so far.

Methods

The following randomised, double-blinded, control trail included 54 patients scheduled for upper limb orthopaedic surgery under general anaesthesia. Preoperative ultrasound-guided (USG) SGB was performed in all patients. Group I (n = 18) received 3.5 mL of a solution (3 mL 2% lignocaine + 0.5 μg/kg dexmedetomidine for SGB) and 15 mL of intravenous (IV) normal saline (NS). Group II (n = 18) received 3.5 mL of a solution (3 mL 2% lignocaine + 0.5 mL NS for SGB) and 15 mL of IV NS. Group III (n = 18) received 3.5 mL of a solution (3 mL 2% lignocaine + 0.5 mL of NS for SGB) and 0.5 μg/kg dexmedetomidine in 15 mL of IV NS. Postoperatively tramadol consumption and Visual Analogue Scale (VAS) score were recorded up to 48 hours.

Results

The cumulative tramadol consumption at the end of 48 hours (p = 0.01) was significantly reduced in the group I as compared to group II. In group I, postoperative VAS at rest was significantly reduced up to 12 hours postoperatively as compared to group II (p = 0.05). The cumulative tramadol consumption was not reduced significantly in group III compared to group II (p = 0.51).

Conclusion

Dexmedetomidine as an adjuvant to SGB along with lignocaine produced a significant tramadol sparing effect and superior analgesia as compared to IV dexmedetomidine and control group.¹.

[Effects of different doses of dexmedetomidine combined with ropivacaine for brachial plexus nerve block in children undergoing polydactyly surgery]

OBJECTIVE

To observe the anesthetic effect and safety of different doses of dexmedetomidine combined with ropivacaine for brachial plexus nerve block in children undergoing polydactyly surgery.

METHODS

Eighty children undergoing polydactyly surgery were randomized into 4 groups to receive brachial plexus nerve block with dexmedetomidine at 0.25, 0.50 or 0.75 µg/kg combined with 0.25% ropivacaine (0.20 mL/kg) (D1, D2, and D3 groups, respectively) or with 0.25% ropivacaine (0.20 mL/kg) only (control group). The onset time, duration of brachial plexus nerve block, awakening time, success rate, and incidence of complications were compared among the groups. Results In D2 and D3 groups, the onset time and awakening time were shorter and anesthesia lasted longer than those in the control group. The onset time and awakening time were shorter and anesthesia maintenance time was longer in D3 group than in D1 group. The success rates of brachial plexus nerve block were significantly higher in D1-3 groups than in the control group (P<0.05). Hematoma was found in one of the patients. In each of the 4 groups, laryngeal nerve block occurred in 1 child and respiratory depression in another; 2 or 3 patients had Horner syndrome, and 1 patient in D3 group experienced an episode of lowered heart beat to below 70 min^-1. All the complications were managed properly and the patients all recovered uneventfully.

CONCLUSION

Brachial plexus nerve block with 0.5 µg/kg dexmedetomidine combined with 0.25% ropivacaine (0.20 mL/kg) is safe for effective anesthesia in children undergoing surgery for polydactyly.

Does Dexmedetomidine Have a Perineural Mechanism of Action When Used as an Adjuvant to Ropivacaine?: A Paired, Blinded, Randomized Trial in Healthy Volunteers

BACKGROUND

Dexmedetomidine used as an adjuvant to local anesthetics may prolong the duration of peripheral nerve blocks. Whether this is mediated by a perineural or systemic mechanism remains unknown. The authors hypothesized that dexmedetomidine has a peripheral mechanism of action.

METHODS

The authors conducted a randomized, paired, triple-blind trial in healthy volunteers. All received bilateral saphenous nerve blocks with 20 ml ropivacaine, 0.5%, plus 1 ml dexmedetomidine, 100 µg/ml, in one thigh and 20 ml ropivacaine 0.5% plus 1 ml saline in the other thigh. The primary outcome measure was the duration of block assessed by temperature sensation (alcohol swab). The secondary outcome measure was the duration of block assessed by pinprick, pain during tonic heat stimulation, warmth detection threshold, and heat pain detection threshold.

RESULTS

All 21 enrolled volunteers completed the trial. The mean duration of block assessed by temperature sensation in the leg receiving ropivacaine plus dexmedetomidine was 22 h (95% CI, 21 to 24) compared to 20 h (95% CI, 19 to 21) in the leg receiving ropivacaine plus placebo with a mean difference of 2 h (95% CI, 1 to 3; P = 0.001). The duration of block was also significantly longer in the leg receiving dexmedetomidine when assessed by pinprick, pain during tonic heat stimulation, and warmth detection threshold but not heat pain detection threshold. One participant experienced numbness in an area in the leg receiving dexmedetomidine.

CONCLUSIONS

Dexmedetomidine prolongs the duration of a saphenous nerve block by a peripheral mechanism when controlling for systemic effects but not necessarily to a clinically relevant extent.

Comparison of effects of ropivacaine with and without dexmedetomidine in axillary brachial plexus block: A prospective randomized double-blinded clinical trial

Background:

Addition of dexmedetomidine to ropivacaine for peripheral nerve blocks has shown to improve the efficacy of ropivacaine by prolonging the duration of analgesia. This study was undertaken to evaluate the effects of ropivacaine alone and in combination with dexmedetomidine in the axillary block.

Materials and Methods:

A total of 80 patients belonging to American Society of Anesthesiologists physical status I, II, and III, scheduled for elective forearm and/or hand surgeries were randomly allocated into one of the two groups to receive either 39 ml of 0.375% ropivacaine and 1 ml normal saline (Group R) or 39 ml of 0.375% ropivacaine and 1 μg/kg dexmedetomidine diluted to 1 ml with normal saline (Group RD).

Results:

There was a significant early the onset of sensory and the motor block in Group RD. Duration of sensory block in Group RD was 677.25 ± 99.64 min and in Group R was 494.38 ± 70.64 min and the difference was clinically significant (P < 0.001). Duration of motor block in Group RD was 712.88 ± 89.32 min and in Group R was 526.25 ± 70.229 min and was clinically significant. Duration of analgesia in Group RD was 764.38 ± 110.275 min and that in Group R was 576.88 ± 76.306 min and was clinically significant. There was a significant alteration in hemodynamics in Group RD when compared to Group R without any side effects.

Conclusion:

Dexmedetomidine as an adjuvant to ropivacaine provides quicker onset of anesthesia, longer duration of analgesia. It offers convenient, simple, effective mode of anesthesia, and postoperative analgesia for forearm and/or hand surgeries.

Local Anesthetic Peripheral Nerve Block Adjuvants for Prolongation of Analgesia: A Systematic Qualitative Review

Background

The use of peripheral nerve blocks for anesthesia and postoperative analgesia has increased significantly in recent years. Adjuvants are frequently added to local anesthetics to prolong analgesia following peripheral nerve blockade. Numerous randomized controlled trials and meta-analyses have examined the pros and cons of the use of various individual adjuvants.

Objectives

To systematically review adjuvant-related randomized controlled trials and meta-analyses and provide clinical recommendations for the use of adjuvants in peripheral nerve blocks.

Methods

Randomized controlled trials and meta-analyses that were published between 1990 and 2014 were included in the initial bibliographic search, which was conducted using Medline/PubMed, Cochrane Central Register of Controlled Trials, and EMBASE. Only studies that were published in English and listed block analgesic duration as an outcome were included. Trials that had already been published in the identified meta-analyses and included adjuvants not in widespread use and published without an Investigational New Drug application or equivalent status were excluded.

Results

Sixty one novel clinical trials and meta-analyses were identified and included in this review. The clinical trials reported analgesic duration data for the following adjuvants: buprenorphine (6), morphine (6), fentanyl (10), epinephrine (3), clonidine (7), dexmedetomidine (7), dexamethasone (7), tramadol (8), and magnesium (4). Studies of perineural buprenorphine, clonidine, dexamethasone, dexmedetomidine, and magnesium most consistently demonstrated prolongation of peripheral nerve blocks.

Conclusions

Buprenorphine, clonidine, dexamethasone, magnesium, and dexmedetomidine are promising agents for use in prolongation of local anesthetic peripheral nerve blocks, and further studies of safety and efficacy are merited. However, caution is recommended with use of any perineural adjuvant, as none have Food and Drug Administration approval, and concerns for side effects and potential toxicity persist.