Guided paravertebral blocks with versus without clonidine for women undergoing breast surgery: a prospective double-blinded randomized study

A Comparative Study of Morphine and Clonidine as an Adjunct to Ropivacaine in Paravertebral Block for Modified Radical Mastectomy

Background General anesthesia (GA) is a standard for breast malignant surgery. The issue of postoperative pain as well as the high occurrence of nausea and vomiting have prompted the quest for a superior methodology for tormenting the executives with fewer complications. Over the most recent couple of years, paravertebral block (PVB) has acquired huge fame either in combination with GA or alone for anesthetic management. In this study, we aim to evaluate the efficacy of morphine and clonidine as an adjunct to ropivacaine in PVB in breast cancer patients undergoing modified radical mastectomy. Methods In this study, a total of 90 patients were divided into the following three groups (30 each) based on a computer-generated random table. Group C (control): PVB with 0.25% ropivacaine (19 ml) 1 ml saline; Group M: PVB with 0.25% ropivacaine (19 ml) + 20 microgram/kg body weight morphine; Group N: PVB with 0.25% ropivacaine (19 ml) + 1.0 microgram/kg body weight clonidine. The postoperative pain intensity was recorded using the visual analog scale (VAS), and sedation was observed by the Ramsay Sedation Scale (RSS) score. Results The VAS was similar at zero hours, two hours, and four hours in the postoperative period among all the groups. There was a significant (p = 0.003) difference in VAS from six hours to 20 hours in the postoperative period among the groups. A significant (p < 0.05) difference was observed among the groups at eight hours to 20 hours. The first requirement of analgesia was significantly (p = 0.001) higher in Group N (7.70 ± 1.74) than in Group C (4.43 ± 1.43) and Group M (7.33 ± 2.21). Conclusion Morphine in the PVB provides better postoperative analgesia. The consumption of rescue analgesia was significantly reduced in the morphine group as compared to the clonidine group. The procedure also proved to be safe as no complication was encountered in the PVB in our study.

Fentanyl versus dexamethasone or both as adjuvants to bupivacaine in an ultrasound-guided paravertebral block in patients undergoing modified radical mastectomy: a randomized double-blind clinical study

BACKGROUND

This study aimed to compare the effect of dexamethasone added to fentanyl and bupivacaine with the effect of either dexamethasone or fentanyl alone when combined with bupivacaine.in the thoracic paravertebral block (TPVB).

METHODS

Sixty female patients (aged 18-60 years), scheduled for modified radical mastectomy were enrolled. Patients received preoperative unilateral paravertebral block using 0.3ml/kg of 0.5% bupivacaine combined with 8 mg dexamethasone (Group I), 1 μg/kg fentanyl (Group II), or 8 mg dexamethasone + 1 μg/kg fentanyl (Group III). The study drugs were diluted with normal saline 0.9% up to 25ml volume. The primary outcome was the time to first postoperative analgesics request, Secondary outcomes were total analgesic consumption, verbal rating pain scale (VRS) over the first 24 hours postoperatively, hemodynamic parameters, and adverse effects.

RESULTS

The time to first analgesic request for intravenous (IV) nalbuphine was longer in group II (15.75 ± 0.9 h, P < 0.001) than group I (10.45±1.1 h, P < 0.001), while no patients requested it in group III (P < 0.001). The total analgesic consumption of IV nalbuphine was lower in group II (8.6 ± 3.5mg, P=0.04) than group I (11.3 ± 2.1mg), with a significant difference between group II and III (P < 0.001). From the 8th till the 24th hours postoperatively, patients in group III showed the significantly lowest median VAS scores, followed by patients in group II (P < 0.001) and lastly patients in group I. There were no significant adverse effects.

CONCLUSIONS

Dexamethasone and fentanyl Combination enhances the analgesic effect of bupivacaine in TPVB.

Analgesic and opioid sparing effects of preoperative thoracic paravertebral block: A double blind evaluation of 0.5% bupivacaine with adrenaline in patients scheduled for simple mastectomy

Background

Various regional anaesthetic techniques are used for post-mastectomy pain relief; however, thoracic paravertebral block (TPVB) has shown some advantages over other methods. This study sought to demonstrate the post-operative benefit of pre-operative TPVB in patients scheduled for simple mastectomy.

Methods

The study was carried out on 60 adult female patients with the American Society of Anesthesiologists physical status Class I to III scheduled for unilateral mastectomy. Pre-operatively, a nerve stimulator was used to locate the paravertebral space thereafter bupivacaine with adrenaline or saline was injected into the space. Post-operatively, intravenous morphine patient controlled analgesia was commenced in the two groups for 24 h after the surgery. In addition, intravenous paracetamol 15 mg/kg was administered 6 hourly for 24 h in both groups.

Results

The 24 h morphine consumption was significantly reduced in the bupivacaine group compared to the control group (P = 0.000). The Numerical pain rating score was significantly lower in the bupivacaine group than in the control group in the 1^st 6 h; P = 0.001. The time to first request for analgesia was significantly longer in the bupivacaine group than the control group (P = 0.000). Nausea was the major side effect detected and this was significantly higher in the control group (P = 0.024). The morphine sparing effect was 65.7% in the bupivacaine group.

Conclusion

The study showed that bupivacaine-based TPVB provided an effective post-operative analgesic and opioid-sparing effect for simple mastectomy when compared with a saline-based control group that received only intravenous morphine patient controlled analgesia and paracetamol.

Effect of Preoperative Duloxetine on Opioid Consumption in Women Undergoing Abdominal Hysterectomy: A Randomized, Double-Blinded, Placebo-Controlled Trial

Background

Pain is one of the most challenging issues following surgery, and it is crucial to provide adequate and appropriate pain control measures.

Objectives

This study assessed the efficacy of preoperative duloxetine in controlling postoperative pain in women following an abdominal hysterectomy in Yas Hospital affiliated to Tehran University of Medical Sciences between December 2019 and April 2020.

Methods

The study involved 80 women who were candidates for elective abdominal hysterectomy. The participants were randomly assigned to one of two groups. Group 1 received a 60 mg duloxetine capsule two hours before surgery. Group 2 received placebo following the same schedule. The amount of administrated opioids and the time from surgery to the administration of opioids were recorded, along with the frequency of nausea and vomiting experienced.

Results

Two patients from each group withdrew before the study ended. In total, 38 women in each group were assessed. There were no significant differences in age, duration of surgery, and the amount of administrated opioids between the two groups. However, the number of patients who had nausea and vomiting differed significantly between the two groups (65% vs. 34%; P = 0.006).

Conclusions

Our findings showed that duloxetine was not effective in controlling pain after abdominal hysterectomy. In addition, patients who received duloxetine had a significantly higher rate of nausea/vomiting.

PROSPECT guideline for oncological breast surgery: a systematic review and procedure-specific postoperative pain management recommendations

Analgesic protocols used to treat pain after breast surgery vary significantly. The aim of this systematic review was to evaluate the available literature on this topic and develop recommendations for optimal pain management after oncological breast surgery. A systematic review using preferred reporting items for systematic reviews and meta-analysis guidance with procedure-specific postoperative pain management (PROSPECT) methodology was undertaken. Randomised controlled trials assessing postoperative pain using analgesic, anaesthetic or surgical interventions were identified. Seven hundred and forty-nine studies were found, of which 53 randomised controlled trials and nine meta-analyses met the inclusion criteria and were included in this review. Quantitative analysis suggests that dexamethasone and gabapentin reduced postoperative pain. The use of paravertebral blocks also reduced postoperative pain scores, analgesia consumption and the incidence of postoperative nausea and vomiting. Intra-operative opioid requirements were documented to be lower when a pectoral nerves block was performed, which also reduced postoperative pain scores and opioid consumption. We recommend basic analgesics (i.e. paracetamol and non-steroidal anti-inflammatory drugs) administered pre-operatively or intra-operatively and continued postoperatively. In addition, pre-operative gabapentin and dexamethasone are also recommended. In major breast surgery, a regional anaesthetic technique such as paravertebral block or pectoral nerves block and/or local anaesthetic wound infiltration may be considered for additional pain relief. Paravertebral block may be continued postoperatively using catheter techniques. Opioids should be reserved as rescue analgesics in the postoperative period. Research is needed to evaluate the role of novel regional analgesic techniques such as erector spinae plane or retrolaminar plane blocks combined with basic analgesics in an enhanced recovery setting.

AAAPT Diagnostic Criteria for Acute Pain Following Breast Surgery

Acute pain after breast surgery decreases the quality of life of cancer survivors. Previous studies using a variety of definitions and methods report prevalence rates between 10% and 80%, which suggests the need for a comprehensive framework that can be used to guide assessment of acute pain and pain-related outcomes after breast surgery. A multidisciplinary task force with clinical and research expertise performed a focused review and synthesis and applied the 5 dimensional framework of the AAAPT (Analgesic, Anesthetic, and Addiction Clinical Trial Translations, Innovations, Opportunities, and Networks [ACTTION], American Academy of Pain Medicine [AAPM], American Pain Society [APS] Pain Taxonomy) to acute pain after breast surgery. Application of the AAAPT taxonomy yielded the following: 1) Core Criteria: Location, timing, severity, and impact of breast surgery pain were defined; 2) Common Features: Character and expected trajectories were established in relevant surgical subgroups, and common pain assessment tools for acute breast surgery pain identified; 3) Modulating Factors: Biological, psychological, and social factors that modulate interindividual variability were delineated; 4) Impact/Functional Consequences: Domains of impact were outlined and defined; 5) Neurobiologic Mechanisms: Putative mechanisms were specified ranging from nerve injury, inflammation, peripheral and central sensitization, to affective and social processing of pain. PERSPECTIVE: The AAAPT provides a framework to define and guide improved assessment of acute pain after breast surgery, which will enhance generalizability of results across studies and facilitate meta-analyses and studies of interindividual variation, and underlying mechanism. It will allow researchers and clinicians to better compare between treatments, across institutions, and with other types of acute pain.

Adding low concentrations of clonidine to ropivacaine for transversus abdominis plane blocks does not reduce plasma ropivacaine levels, suggesting a lack of vasoconstrictor effect

Clonidine has been used successfully to prolong the duration of action of local anaesthetics in peripheral nerve blocks, but its mechanism of action in this setting remains unclear. Some studies suggest that clonidine exerts a vasoconstrictor effect, limiting the washout of local anaesthetic from its site of deposition. We investigated this potential vasoconstrictor effect, using plasma ropivacaine concentrations as a surrogate measure of vasoconstriction, in patients who received transversus abdominis plane (TAP) blocks with and without clonidine. Eighty women undergoing laparoscopic gynaecological surgery were randomly assigned to receive one of four TAP block solutions: 0.2% ropivacaine (control), ropivacaine with clonidine 2 μg/kg (clonidine), ropivacaine with 1:400,000 adrenaline (adrenaline) or ropivacaine and a subcutaneous injection of clonidine 2 μg/kg (SC clonidine). The primary outcome was total venous plasma ropivacaine concentrations up to 6 h after the block. There were no significant differences in plasma ropivacaine concentrations between the control group and the clonidine group at any timepoint in the study, nor were there differences in either the mean maximum ropivacaine concentration ( C_max) (1.99 μg/mL versus 2.05 μg/mL, P = 0.712) or the time to maximum concentration ( T_max) (51.0 min versus 56.0 min, P = 0.537). The SC clonidine group also did not differ significantly from the controls ( C_max 2.13 μg/mL versus 1.99 μg/mL, P = 0.424; T_max 43.5 min versus 51.0 min, P = 0.201). Plasma ropivacaine concentrations in the adrenaline group were significantly lower than the controls from 10 to 90 min ( P < 0.003 for each comparison), and the C_max was less than that of the control group (1.36 μg/mL versus 1.99 μg/mL, P < 0.001) with a longer T_max (103.5 min versus 51.0 min, P = 0.001). These findings indicate that clonidine at a concentration of 1.35 μg/mL added to ropivacaine for TAP blocks did not produce a reduction in plasma ropivacaine concentrations. This suggests a lack of vasoconstrictor effect during TAP blocks. Further studies should evaluate whether vasoconstriction occurs when clonidine is used at higher concentrations or for other blocks.

Comparison of Morphine and Clonidine as Adjuvants in Paravertebral Block

BACKGROUND

General anesthesia (GA) has been considered as the gold standard for breast cancer surgery. The problem of postoperative pain as well as the high incidence of nausea and vomiting has led to the search for a better modality for pain management with fewer side effects. In the last few years, paravertebral block (PVB) has gained immense popularity either in combination with GA or by itself for the anesthetic management of patients undergoing breast surgery.

CONTEXT

Paravertebral block in breast surgery.

AIMS

This study aims to evaluate the efficacy and duration of postoperative analgesia provided by ultrasound (USG)-guided PVB with bupivacaine and morphine versus bupivacaine and clonidine in patients undergoing modified radical mastectomy (MRM).

SUBJECT AND METHODS

In the study, 70 patients who were scheduled for MRM were enrolled and randomly divided into Group M (n = 35) and Group C (n = 35). Both groups received USG-guided PVB at T2-T3 after administering GA. Group M received 2 mg/kg 0.5% bupivacaine with 0.05 mg/kg morphine and Group C received 2 mg/kg 0.5% bupivacaine with 1 μg/kg clonidine in the block. Postoperatively, pain intensity was recorded using the visual analog scale (VAS) (0-10 scale) at 1, 2, 6, 18, and 24 h duration when patients were resting and during a standardized movement. Modified Post Anaesthesia Discharge Scoring System was assessed at 1, 2, 6, 18 and 24 h after surgery.

RESULTS

In this study conducted on 70 patients, VAS scores (both at rest and on movement) were found comparable at postoperative 1, 2, 6, 18, and 24 h (P > 0.05). There was no statistical difference in comparing postanesthesia discharging scoring in both the groups. No incidence of postoperative nausea and vomiting was seen in any group.

CONCLUSIONS

Morphine and clonidine in PVB are equally effective, and there is no superiority of one agent over the other. Hence, both drugs may be used with equal efficacy as adjuvants to bupivacaine in PVB for providing postoperative analgesia.

The Trajectory of Postoperative Pain Following Mastectomy with and without Paravertebral Block

Evidence to support the argument that general anesthesia (GA) with paravertebral block (PVB) provides better pain relief for mastectomy patients than GA alone is contradictory. The aim of this study was to explore pain and analgesia after mastectomy with or without PVB during acute inpatient recovery. A retrospective study was conducted in a single hospital providing specialist cancer services in metropolitan Melbourne, Australia. We explored pain and concomitant analgesic administration in 80 consecutive women recovering from mastectomy who underwent GA with (n = 40) or without (n = 40) PVB. A pain management index (PMI) was derived to illustrate the efficacy of management from day of surgery (DOS) to postoperative day (POD) 3. Patients who reported no pain progressively increased from DOS (n = 12, 15%) to POD 3 (n = 54, 67.5%). Most patients were administered analgesics as a combination of acetaminophen and a strong opioid on DOS (n = 53, 66.2%), POD 1 (n = 45, 56.2%), POD 2 (n = 33, 41.2%), and POD 3 (n = 21, 26.2%). Less than 6% of patients on any POD were administered multimodal anlagesics. PMI scores indicate some pain in the context of receiving weak and strong opioids for GA patients and more frequent use of nonopioid analgesics in PVB patients during recovery. These findings highlight the need for data describing patterns of analgesic administration in addition to reports of postoperative pain to determine the most effective means of avoiding postoperative pain in patients who require mastectomy.

A review of postoperative analgesia for breast cancer surgery

An online database search with subsequent article review was performed in order to review the various analgesic modalities for breast cancer surgery. Of 514 abstracts, 284 full-length manuscripts were reviewed. The effect of pharmacologic interventions is varied (NSAIDS, opioids, anticonvulsants, ketamine, lidocaine). Likewise, data from high-quality randomized, controlled studies on wound infiltration (including liposome encapsulated) and infusion of local anesthetic are minimal and conflicting. Conversely, abundant evidence demonstrates paravertebral blocks and thoracic epidural infusions provide effective analgesia and minimize opioid requirements, while decreasing opioid-related side effects in the immediate postoperative period. Other techniques with promising – but extremely limited – data include cervical epidural infusion, brachial plexus, interfascial plane and interpleural blocks. In conclusion, procedural interventions involving regional blocks are more conclusively effective than pharmacologic modalities in providing analgesia to patients following surgery for breast cancer.

Nerve stimulator-guided pudendal nerve block vs general anesthesia for postoperative pain management after anterior and posterior vaginal wall repair: a prospective randomized trial

STUDY OBJECTIVE

Compare the effectiveness of nerve stimulator-guided pudendal nerve block (PNB) vs general anesthesia (GA) for anterior and posterior (AP) colporrhaphy in terms of pain relief and analgesic consumption within 24 and 48 hours postoperatively.

DESIGN

Prospective randomized trial.

PATIENTS

Fifty-seven patients whose ages ranged between 20 and 53 years scheduled to undergo AP colporrhaphy due to the presence of cystorectocele.

INTERVENTIONS

Patients were randomly assigned into 2 groups receiving either nerve stimulator-guided PNB (n = 28) or GA (n = 29). A total volume of 0.7 mL/kg of the local anesthetic mixture was injected at 4 sites.

MAIN RESULTS

Both groups were similar with respect to age, weight, height, and surgery duration. There was a significant difference in average pain scores within the first and second postoperative days (P values = .005 and .004, respectively). Total analgesic consumption (ketoprofen and tramadol) was significantly lower in the PNB within the first (P values = .018 and .010) and second postoperative days (P values = .041 and .011), respectively. Return to normal daily activity was significantly (P< .0001) shorter in the PNB group compared with the GA group (3.6 days vs 12.2 days). A total of 71.4% of the patients in the PNB group were satisfied compared with 27.8% in the GA group (P< .0001). Surgeon satisfaction was significantly higher in the PNB group (82.1% vs 34.5%, P< .0001).

CONCLUSION

This randomized controlled trial demonstrated that nerve stimulator-guided PNB could be used as an alternative to GA for AP repair of stages I and II prolapse because it is associated with less postoperative pain and analgesic consumption, in addition to shorter duration of recovery.

Additives to local anesthetics for peripheral nerve blocks or local anesthesia: a review of the literature

SUMMARY 

A multitude of studies have focused on individual additives to local anesthetics and their effect on quality, onset, duration, spread and selectivity, as well as the potential toxic effects of their use. This review aims to give a broad overview of the current evidence in this developing field, based on beneficial and adverse effects of these drugs. We discuss the limitations of the available data and hope to convey implications and future perspectives for clinicians and researchers alike.

Perineural dexamethasone to improve postoperative analgesia with peripheral nerve blocks: a meta-analysis of randomized controlled trials

Background. The overall effect of perineural dexamethasone on postoperative analgesia outcomes has yet to be quantified. The main objective of this quantitative review was to evaluate the effect of perineural dexamethasone as a nerve block adjunct on postoperative analgesia outcomes. Methods. A systematic search was performed to identify randomized controlled trials that evaluated the effects of perineural dexamethasone as a block adjunct on postoperative pain outcomes in patients receiving regional anesthesia. Meta-analysis was performed using a random-effect model. Results. Nine randomized trials with 760 subjects were included. The weighted mean difference (99% CI) of the combined effects favored perineural dexamethasone over control for analgesia duration, 473 (264 to 682) minutes, and motor block duration, 500 (154 to 846) minutes. Postoperative opioid consumption was also reduced in the perineural dexamethasone group compared to control, -8.5 (-12.3 to -4.6) mg of IV morphine equivalents. No significant neurological symptoms could have been attributed to the use of perineural dexamethasone. Conclusions. Perineural dexamethasone improves postoperative pain outcomes when given as an adjunct to brachial plexus blocks. There were no reports of persistent nerve injury attributed to perineural administration of the drug.

Multimodal therapy in perioperative analgesia

This article reviews the current evidence for multimodal analgesic options for common surgical procedures. As perioperative physicians, we have come a long way from using only opioids for postoperative pain to combinations of acetaminophen, nonsteroidal anti-inflammatory drugs (NSAIDs), selective Cyclo-oxygenase (COX-2) inhibitors, local anesthetics, N-methyl-d-aspartate (NMDA) receptor antagonists, and regional anesthetics. As discussed in this article, many of these agents have decreased narcotic requirements, improved patient satisfaction, and decreased postanesthesia care unit (PACU) times, as well as morbidity in the perioperative period.