Blood bupivacaine concentrations after pecto-serratus and serratus anterior plane injections of plain and liposomal bupivacaine in robotically-assisted mitral valve surgery: Sub-study of a randomized trial

STUDY OBJECTIVE

To investigate the timing of peak blood concentrations and potential toxicity when using a combination of plain and liposomal bupivacaine for thoracic fascial plane blocks.

DESIGN

Pharmacokinetic analysis.

SETTING

Operating room.

PATIENTS

Eighteen adult patients undergoing robotically-assisted mitral valve surgery.

INTERVENTIONS

Ultrasound-guided pecto-serratus and serratus anterior plane blocks using a mixture of 0.5% bupivacaine HCl up to 2.5 mg/kg and liposomal bupivacaine up to 266 mg.

MEASUREMENTS

Arterial plasma bupivacaine concentration.

MAIN RESULTS

Samples from 13 participants were analyzed. There was substantial inter-patient variability in plasma concentrations. A geometric mean maximum bupivacaine concentration was 1492 ng/ml (range 660 to 4650 ng/ml) at median time of 30 min after injection. In 4/13 (31%) patients, plasma bupivacaine concentrations exceeded our predefined 2000 ng/ml toxic threshold. A second much smaller peak was observed about 32 h after the injection. No obvious signs of local anesthetic toxicity were observed.

CONCLUSIONS

Combined injection of plain and liposomal bupivacaine for pecto-serratus/serratus anterior plane blocks produced a biphasic pattern, with the highest arterial plasma concentrations observed within 30 min. Maximum concentrations exceeded the potential toxic threshold in nearly a third of patients, but without clinical evidence of toxicity. Clinicians should not assume that routine combinations of plain and liposomal bupivacaine for thoracic fascial plane blocks are inherently safe.

TXNIP knockdown protects rats against bupivacaine-induced spinal neurotoxicity via the inhibition of oxidative stress and apoptosis

Bupivacaine (BUP) is an anesthetic commonly used in clinical practice that when used for spinal anesthesia, might exert neurotoxic effects. Thioredoxin-interacting protein (TXNIP) is a member of the α-arrestin protein superfamily that binds covalently to thioredoxin (TRX) to inhibit its function, leading to increased oxidative stress and activation of apoptosis. The role of TXNIP in BUP-induced oxidative stress and apoptosis remains to be elucidated. In this context, the present study aimed to explore the effects of TXNIP knockdown on BUP-induced oxidative stress and apoptosis in the spinal cord of rats and in PC12 cells through the transfection of adeno-associated virus-TXNIP short hairpin RNA (AAV-TXNIP shRNA) and siRNA-TXNIP, respectively. In vivo, a rat model of spinal neurotoxicity was established by intrathecally injecting rats with BUP. The BUP + TXNIP shRNA and the BUP + Control shRNA groups of rats were injected with an AAV carrying the TXNIP shRNA and the Control shRNA, respectively, into the subarachnoid space four weeks prior to BUP treatment. The Basso, Beattie & Bresnahan (BBB) locomotor rating score, % MPE of TFL, H&E staining, and Nissl staining analyses were conducted. In vitro, 0.8 mM BUP was determined by CCK-8 assay to establish a cytotoxicity model in PC12 cells. Transfection with siRNA-TXNIP was carried out to suppress TXNIP expression prior to exposing PC12 cells to BUP. The results revealed that BUP effectively induced neurological behavioral dysfunction and neuronal damage and death in the spinal cord of the rats. Similarly, BUP triggered cytotoxicity and apoptosis in PC12 cells. In addition, treated with BUP both in vitro and in vivo exhibited upregulated TXNIP expression and increased oxidative stress and apoptosis. Interestingly, TXNIP knockdown in the spinal cord of rats through transfection of AAV-TXNIP shRNA exerted a protective effect against BUP-induced spinal neurotoxicity by ameliorating behavioral and histological outcomes and promoting the survival of spinal cord neurons. Similarly, transfection with siRNA-TXNIP mitigated BUP-induced cytotoxicity in PC12 cells. In addition, TXNIP knockdown mitigated the upregulation of ROS, MDA, Bax, and cleaved caspase-3 and restored the downregulation of GSH, SOD, CAT, GPX4, and Bcl2 induced upon BUP exposure. These findings suggested that TXNIP knockdown protected against BUP-induced spinal neurotoxicity by suppressing oxidative stress and apoptosis. In summary, TXNIP could be a central signaling hub that positively regulates oxidative stress and apoptosis during neuronal damage, which renders TXNIP a promising target for treatment strategies against BUP-induced spinal neurotoxicity.

A phase 3 active-controlled trial of liposomal bupivacaine via sciatic nerve block in the popliteal fossa after bunionectomy

STUDY OBJECTIVE

To investigate the efficacy, safety, pharmacodynamics, and pharmacokinetics of liposomal bupivacaine (LB) administered via ultrasound-guided sciatic nerve block in the popliteal fossa in participants undergoing bunionectomy.

DESIGN

Two-part, randomized, double-blind, active-controlled trial (NCT05157841).

SETTING

Operating room, postanesthesia care unit, and health care facility (6 sites).

PATIENTS

Adults with American Society of Anesthesiologists physical status classification ≤3 and body mass index ≥18 to <40 kg/m2 undergoing elective distal metaphyseal osteotomy.

INTERVENTIONS

Part A participants were randomized 1:1:1 to LB 266 mg, LB 133 mg, or bupivacaine hydrochloride 50 mg (BUPI). Part B participants were randomized 1:1 to LB (at the dose established by part A) or BUPI.

MEASUREMENTS

The primary endpoint was area under the curve (AUC) of numerical rating scale (NRS) pain intensity scores 0-96 h after surgery. Secondary endpoints included total postsurgical opioid consumption, opioid-free status 0-96 h after surgery, and pharmacokinetic endpoints.

MAIN RESULTS

Part A enrolled 22 participants per group. In part B, additional participants were randomized to LB 133 mg (n = 59) and BUPI (n = 60) (185 total). LB 133 mg had significant reductions versus BUPI in the AUC of NRS pain intensity score (least squares mean [LSM], 207.4 vs 371.4; P < 0.00001) and total opioid consumption 0-96 h after surgery (LSM, 17.7 [95% confidence interval (CI), 13.7, 22.8] morphine milligram equivalents [MMEs] vs 45.3 [95% CI, 35.1, 58.5] MMEs; P < 0.00001) and an increased proportion of opioid-free participants (24.4% vs 6%; odds ratio, 5.04 [95% CI, 2.01, 12.62]; P = 0.0003) in parts A + B. Adverse events were similar across groups.

CONCLUSIONS

LB 133 mg administered via sciatic nerve block in the popliteal fossa after bunionectomy demonstrated superior and long-lasting postsurgical pain control versus BUPI. The clinical relevance of these findings is supported by concurrent reductions in pain and opioid consumption over 4 days after surgery and a significantly greater percentage of participants remaining opioid-free.

Toxic effects of local anesthetics on rat fibroblasts: An in-vitro study

BACKGROUND

Infusion catheters facilitate a controlled infusion of local anesthetic (LA) for pain control after surgery. However, their potential effects on healing fibroblasts are unspecified.

METHODS

Rat synovial fibroblasts were cultured in 12-well plates. Dilutions were prepared in a solution containing reduced-serum media and 0.9% sodium chloride in 1:1 concentration. Each well was treated with 500 μl of the appropriate LA dilution or normal saline for 15- or 30-min. LA dilutions included: 0.5% ropivacaine HCl, 0.2% ropivacaine HCl, 1% lidocaine HCl and epinephrine 1:100,000, 1% lidocaine HCl, 0.5% bupivacaine HCl and epinephrine 1:200,000, and 0.5% bupivacaine HCl. This was replicated three times. Dilution of each LA whereby 50% of the cells were unviable (Lethal dose 50 [LD50]) was analyzed.

RESULTS

LD50 was reached for lidocaine and bupivacaine, but not ropivacaine. Lidocaine 1% with epinephrine is toxic at 30-min at 1/4 and 1/2 sample dilutions. Bupivacaine 0.5% was found to be toxic at 30-min at 1/2 sample dilution. Bupivacaine 0.5% with epinephrine was found to be toxic at 15- and 30-min at 1/4 sample dilution. Lidocaine 1% was found to be toxic at 15- and 30-min at 1/2 sample dilution. Ropivacaine 0.2% and 0.5% remained below LD50 at all time-points and concentrations, with 0.2% demonstrating the least cell death.

CONCLUSIONS

Though pain pumps are generally efficacious, LAs may inhibit fibroblasts, including perineural fibroblast and endoneurial fibroblast-like cells, which may contribute to persistent nerve deficits, delayed neurogenic pain, and negatively impact healing. Should a continuous infusion be used, our data supports ropivacaine 0.2%.

LEVEL OF EVIDENCE

Basic Science Study; Animal model.

Comparison of sequential and mixture injections of opioids and hyperbaric bupivacaine for subarachnoid block for lower segment caesarean section: a randomised controlled study

INTRODUCTION

Opioids are commonly added to local anaesthetic for subarachnoid block for caesarean section due to their synergistic effects. The physiochemical characteristics of opioids suggest premixing with hyperbaric bupivacaine may limit their distribution within the CSF. We studied the effect of a separate injection with a combination of bupivacaine, morphine and fentanyl on block characteristics, haemodynamic changes, postoperative pain and patient satisfaction.

METHOD

Following ethical approval and informed consent, a prospective double-blinded randomised controlled trial was performed in a university hospital. A total of 126 patients undergoing caesarean section were randomised to two groups. In group M, the premixed group, patients received 12 mg of hyperbaric bupivacaine, 20 mcg of fentanyl and 100 mcg of morphine injected as a single mixture. In group S, the separate injection group, patients received the same drugs in separate injections. Measurements included haemodynamics, block distribution, intra- and postoperative pain, as well as patient satisfaction.

RESULTS

Patients in both groups had similar block height, time to maximum sensory block, time to block regression and motor block. However, haemodynamics were different between the groups. The proportion of systolic hypotension episodes was greater in group S [159/1320 (12.05%)] than group M [113/1452 (7.78%)], with P = 0.0002. Moreover, a greater amount of ephedrine was administered in group S than group M, with values 12.09 (8.1) and 9.09 (8.5) mg respectively (P = 0.001). Additionally, postoperative pain, as measured by the Visual Analogue Scale (VAS), was greater in group M, with a VAS of 4.6 (1.7), vs. group S, which recorded a VAS of 3.8 (2.0) (P = 0.017).

CONCLUSION

Sequential injection of intrathecal opioids and hyperbaric bupivacaine resulted in greater early haemodynamic instability and slightly better postoperative analgesia without any difference in block height or patient satisfaction.

CLINICAL TRIAL REGISTRATION

NCT04403724.

Super-refractory status epilepticus, rhabdomyolysis, central hyperthermia and cardiomyopathy attributable to spinal anesthesia: a case report and review of literature

BACKGROUND

There are only six past reports of super-refractory status epilepticus induced by spinal anesthesia. None of those patients have died. Only < 15 mg of bupivacaine was administered to all six of them and to our case. Pathophysiology ensuing such cases remains unclear.

CASE PRESENTATION

A 27 year old gravida 2, para 1, mother at 37 weeks of gestation came to the operating theater for an elective cesarean section. She had no significant medical history other than controlled hypothyroidism and one episode of food allergy. Her current pregnancy was uneventful. Her American Society of Anesthesiologists (ASA) grade was 2. She underwent spinal anesthesia and adequate anesthesia was achieved. After 5-7 min she developed a progressive myoclonus. After delivery of a healthy baby, she developed generalized tonic clonic seizures that continued despite the induction of general anesthesia. She had rhabdomyolysis, one brief cardiac arrest and resuscitation, followed by stress cardiomyopathy and central hyperthermia. She died on day four. There were no significant macroscopic or histopathological changes in her brain that explain her super refractory status epilepticus. Heavy bupivacaine samples of the same batch used for this patient were analyzed by two specialized laboratories. National Medicines Quality Assurance Laboratory of Sri Lanka reported that samples failed to confirm United States Pharmacopeia (USP) dextrose specifications and passed other tests. Subsequently, Therapeutic Goods Administration of Australia reported that the drug passed all standard USP quality tests applied to it. Nonetheless, they have detected an unidentified impurity in the medicine.

CONCLUSIONS

After reviewing relevant literature, we believe that direct neurotoxicity by bupivacaine is the most probable cause of super-refractory status epilepticus. Super-refractory status epilepticus would have led to her other complications and death. We discuss probable patient factors that would have made her susceptible to neurotoxicity. The impurity in the drug detected by one laboratory also would have contributed to her status epilepticus. We propose several possible mechanisms that would have led to status epilepticus and her death. We discuss the factors that shall guide investigators on future such cases. We suggest ways to minimize similar future incidents. This is an idiosyncratic reaction as well.

Apelin-13 reverses bupivacaine-induced cardiotoxicity: an experimental study

INTRODUCTION

Cardiac arrest or arrhythmia caused by bupivacaine may be refractory to treatment. Apelin has been reported to directly increase the frequency of spontaneous activation and the propagation of action potentials, ultimately promoting cardiac contractility. This study aimed to investigate the effects of apelin-13 in reversing cardiac suppression induced by bupivacaine in rats.

METHODS

A rat model of cardiac suppression was established by a 3-min continuous intravenous infusion of bupivacaine at the rate of 5 mg.kg-1.min-1, and serial doses of apelin-13 (50, 150 and 450 μg.kg-1) were administered to rescue cardiac suppression to identify its dose-response relationship. We used F13A, an inhibitor of Angiotensin Receptor-Like 1 (APJ), and Protein Kinase C (PKC) inhibitor chelerythrine to reverse the effects of apelin-13. Moreover, the protein expressions of PKC, Nav1.5, and APJ in ventricular tissues were measured using Western blotting and immunofluorescence assay.

RESULTS

Compared to the control rats, the rats subjected to continuous intravenous administration of bupivacaine had impaired hemodynamic stability. Administration of apelin-13, in a dose-dependent manner, significantly improved hemodynamic parameters in rats with bupivacaine-induced cardiac suppression (p < 0.05), and apelin-13 treatment also significantly upregulated the protein expressions of p-PKC and Nav1.5 (p < 0.05), these effects were abrogated by F13A or chelerythrine (p < 0.05).

CONCLUSION

Exogenous apelin-13, at least in part, activates the PKC signaling pathway through the apelin/APJ system to improve cardiac function in a rat model of bupivacaine-induced cardiac suppression.

To Compare the Effects of Post-tonsillectomy Intra-operative Infiltration of Ropivacaine Versus Bupivacaine in Tonsillar Fossa

Tonsillectomy is one of the most common surgical procedures practiced in Otorhinolaryngology. A significant obstacle for the speedy and smooth recovery is early post- operative pain. Pain leads to negative outcomes such as poor intake, tachycardia, anxiety, delayed wound healing and insomnia. Aim to assess and compare the effect of post-incisional infiltration of 0.75% Ropivacaine v/s 0.5% Bupivacaine on post tonsillectomy pain, the on start of oral intake and stay in hospital and to investigate any complications that can arise due to infiltration of the said drugs. 60 Patients above the age of 5 years were posted for tonsillectomy or adenotonsillectomy under general anesthesia. Patients were blinded about the group in which they will be enrolled. Group A received Inj. ropivacaine (0.75%) 2 ml and Group B: received Inj. Bupivacaine (0.50%) 2 ml in each fossa. After surgery, no analgesics were given & patients were observed for the intensity of post-operative pain in the immediate post-operative period, at 2, 4, 6, 12, 24, 48 h and further if not discharged using VISUAL ANALOGUE SCORE (VAS) and VERBAL RATING SCALE(VRS). Post-operative pain assessment was done using VAS and VRS at 2nd, 4th, 6th, 12th, 24th and 48th hour which was found to be lower in Group 'A'. Patients in Group 'A' also started their oral intake sooner, had lesser hospitalization days than group 'B' patients. Longer time for Rescue analgesic and reduced total dose of analgesic required was seen in Group A compared to Group B. This comparative study on Post-incisional infiltration of 2 ml 0.75% Ropivacaine v/s 2 ml 0.5% Bupivacaine has shown that Ropivacaine is a more effective drug in reducing post-operative pain in comparison to Bupivacaine, proven statistically.

Comparison the effect of bupivacaine plus magnesium sulfate with ropivacaine plus magnesium sulfate infiltration on postoperative pain in patients undergoing lumbar laminectomy with general anesthesia

PURPOSE

In this study, we investigated the effect of local injection of ropivacaine and bupivacaine with magnesium sulfate on postoperative pain in vertebral laminectomy surgery.

DESIGN

This randomized double-blind prospective study was conducted among 60 patients aged 18-65 years old with ASA class I and II.

METHODS

Group RM: (30 people) received 70 mg ropivacaine (14 ml) plus 1 ml magnesium sulfate (500 mg) volume up to 20 ml with normal saline. Group BM: (30 people) received 70 mg bupivacaine (14 ml) plus 1 ml magnesium sulfate (500 mg) volume up to 20 ml with normal saline. The results were analyzed by SPSS 23 software, and statistical analysis consisted of χ2 test and t-test, and a p value less than .05 was considered significant.

FINDINGS

Mean pain score based on VAS in 6 and 12 h after surgery in the RM group was lower in the BM group (p < 0.05). The analgesic request frequency in the RM group was lower than the BM group (p = 0.01). The mean morphine consumption in the RM group was 185 mg and in the BM group was 220 mg. According to the T-test, there was a significant difference between the two groups (p = 0.03). there was no significant difference between the mean arterial blood pressure and mean heart rate between the two groups at 6, 12, 24 and 24 h after surgery (p > 0.05).

CONCLUSION

This study showed that wound infiltration with ropivacaine and magnesium sulfate compared to bupivacaine and magnesium sulfate provided better postoperative analgesia and significantly reduced postoperative opioid consumption in patients undergoing lumbar laminectomy.

[Translated article] In vitro elution of local anaesthetics from PMMA bone cement

BACKGROUND AND AIM

Currently, we do not have a gold standard for pain management after total knee arthroplasty. We may use one of more drug delivery systems, none of which are ideal. An ideal depot delivery system would provide therapeutic, nontoxic, doses of drug at the surgical side, especially during 72h postoperatively. The bone cement used in arthroplasties has been used as a drug delivery system, especially antibiotics, since 1970. Based on this principle, we developed this study with the aim to characterize the elution profile of two local anaesthetics (lidocaine hydrochloride and bupivacaine hydrochloride) from PMMA (polymethilmethacrylate) bone cement.

MATERIAL AND METHODS

Palacos® R+G bone cement and lidocaine hydrochloride or bupivacaine hydrochloride specimens were obtained depending on the study group. These specimens were immersed in PBS (phosphate buffered saline) and removed from the solution at different set times. Subsequently, the concentration of local anaesthetic in the liquid was analyzed by liquid chromatography.

RESULTS

The percentage of lidocaine eluted from PMMA bone cement in this study was 9.74% of the total lidocaine content per specimen at 72h and 18.73% at 336h (14 days). In case of bupivacaine, the elution percentage was 2.71% of the total bupivacaine content per specimen at 72h and 2.70% at 336h (14 days).

CONCLUSIONS

Local anaesthetics elute in vitro from PMMA bone cement, reaching doses at 72h close to the doses used in anaesthetic blocks.

Defective autophagy contributes to bupivacaine-induced aggravation of painful diabetic neuropathy in db/db mice

Current evidence suggests that hyperactivated or impaired autophagy can lead to neuronal death. The effect of local anesthetics on painful diabetic neuropathy (PDN) and the role of autophagy in the above pathological process remain unclear, warranting further studies. So, PDN models were established by assessing the paw withdrawal threshold (PWT) and paw withdrawal latency (PWL) in leptin gene-mutation (db/db) mice. Wild type (WT) and PDN mice received intrathecal 0.75% bupivacaine or/with intraperitoneal drug treatment (rapamycin or bafilomycin A1). Subsequently, the PWT and PWL were measured to assess hyperalgesia at 6 h, 24 h, 30 h, and 48 h after intrathecal bupivacaine. Also, sensory nerve conduction velocity (SNCV) and motor nerve conduction velocity (MNCV) were measured before and 48 h after intrathecal bupivacaine treatment. The spinal cord tissue of L4-L6 segments and serum were harvested to evaluate the change of autophagy, oxidative stress, oxidative injury, and apoptosis. We found that bupivacaine induced the activation of autophagy but did not affect the pain threshold, SNCV and MNCV in WT mice at predefined time points. Conversely, bupivacaine lowered autophagosome generation and degradation, slowed SNCV and aggravated spinal dorsal horn neuron oxidative injury and hyperalgesia in PDN mice. The autophagy activator (rapamycin) could decrease spinal dorsal horn neuron oxidative injury, alleviate the alterations in SNCV and hyperalgesia in bupivacaine-treated PDN mice. Meanwhile, the autophagy inhibitor (bafilomycin A1) could exacerbate spinal dorsal horn neuron oxidative injury, the alterations in SNCV and hyperalgesia in bupivacaine-treated PDN mice. Our results showed that bupivacaine could induce defective autophagy, slowed SNCV and aggravate spinal dorsal horn neuron oxidative injury and hyperalgesia in PDN mice. Restoring autophagy may represent a potential therapeutic approach against nerve injury in PDN patients with local anesthesia and analgesia.

Notoginsenoside R1 attenuates bupivacaine induced neurotoxicity by activating Jak1/Stat3/Mcl1 pathway

Bupivacaine, a common amide local anesthetic, can provide effective analgesia or pain relief but can also cause neurotoxicity, which remains a mounting concern in clinic and animal care. However, the precise underlying mechanisms have not been fully elucidated. A natural compound, notoginsenoside R1 (NG-R1) has been reported to exhibit a neuroprotective role in stress conditions. In this study, we explored the function and mechanism of NG-R1 in alleviating bupivacaine-induced neurotoxicity in mouse hippocampal neuronal (HT-22) and mouse neuroblastoma (Neuro-2a) cell lines. Our results exhibited that NG-R1 treatment can significantly rescue the decline of cell survival induced by bupivacaine. Tunel staining and western blotting showed that NG-R1 could attenuate BPV‑induced cell apoptosis. Besides, we focused on Mcl1 as a potential target as it showed opposite expression tendency in response to NG-R1 and bupivacaine exposure. Mcl1 knockdown blocked the inhibitory effect of NG-R1 on cell apoptosis against bupivacaine treatment. Intriguingly, we found that NG-R1 can upregulate Mcl1 transcription by activating Stat3 and promote its nuclear translocation. In addition, NG-R1 can also promote Jak1 phosphorylation and docking analysis provide a predicted model for interaction between NG-R1 and phosphorylated Jak1. Taken together, our results demonstrated that NG-R1 can attenuate bupivacaine induced neurotoxicity by activating Jak1/Stat3/Mcl1 pathway.

The use of granisetron on bupivacaine induced sciatic nerve block in rats

PURPOSE

The effects of the 5-hydroxytryptamine (5-HT3) receptor antagonists on regional anaesthesia are complex and unclear. The present study was designed to test the hypothesis that granisetron, a selective 5-HT3 receptor antagonist, would decrease the duration of motor block, sensory block, and proprioception in a dose-dependent fashion in a rat model of bupivacaine-induced sciatic nerve blockade.

MATERIALS AND METHODS

Thirty-eight male Wistar Albino rats that received unilateral sciatic nerve blocks were randomly divided into five experimental groups. Group B received a perineural of 0.3 ml of bupivacaine alone; Group BG800 received perineural 0.3 ml of bupivacaine and 800 µg of granisetron 10 min later; Group BG1200 received perineural 0.3 ml of bupivacaine and 1200 µg of granisetron 10 min later; Group BG1200IP received a perineural 0.3 ml of bupivacaine and an intraperitoneal injection of 1200 µg of granisetron 10 min later; and Group S was sham operated. A blinded investigator assessed motor, sensory and proprioception function every 10 min until the return of normal function.

RESULTS

The medians for recovery times in Group B, Group BG800, Group BG1200, and Group BG1200IP were 105, 64, 85, and 120 min for motor function, respectively; 80, 64, 84, and 104 min for sensory function; 80, 63, 85, and 108 min were calculated for the proprioception function. The time to the return of normal motor, sensory, and proprioception function was not statistically significantly different between the groups (p > 0.05). Motor block did not develop in any of the rats in Group S.

CONCLUSIONS

Local and systemic application of granisetron was not significantly decrease the duration of bupivacaine induced motor, sensory, and proprioception block of sciatic nerve in rat.

Comparison of Ropivacaine versus Bupivacaine in Spinal-Induced Hypotension in Preeclampsia Patients: A Randomized Control Trial

Background

Spinal anesthesia is considered to be the safest method of anesthesia for cesarean sections in patients with preeclampsia. Patients with preeclampsia are at an increased risk of experiencing severe hypotension following spinal anesthesia, which could have more profound and deleterious effects on both the fetus and the mother. However, bupivacaine, the most commonly used drug, can induce severe hypotension even at low doses. The purpose of this study is to minimize post-spinal hypotension in both the mother and the fetus.

Objectives

To determine and compare the reduction in hypotension following spinal anesthesia in patients with preeclampsia between the ropivacaine and bupivacaine groups.

Methods

In a randomized clinical trial, a total of 90 parturients with preeclampsia undergoing spinal anesthesia were enrolled and randomly divided into 2 groups: One receiving ropivacaine and the other receiving bupivacaine. The dose of spinal ropivacaine was 15 mg of a 0.5% solution, and the dose of bupivacaine was also 15 mg of a 0.5 % solution. Hemodynamic parameters, including systolic and diastolic blood pressure and heart rate, were recorded following the administration of spinal anesthesia. Pain scores and the time until the return of motor movement were also documented.

Results

For statistical analysis, the t-test, Chi-square, and ANOVA tests were utilized to compare the groups. Demographic variables, including maternal age, gestational age, parity, and gravidity, were not significantly different between the 2 groups. The trend of mean systolic blood pressure (SBP) was significantly lower in the bupivacaine group compared to the ropivacaine group at all measured time points in the study (P < 0.05). The amount of ephedrine used after spinal anesthesia was significantly different at 2 and 4 minutes in the ropivacaine group compared to the bupivacaine group (P = 0.012, P = 0.025). Post-operative pain scores at 1 hour in recovery were not significantly different between the ropivacaine and bupivacaine groups (P = 0.015). The time to knee movement was also significantly shorter in the ropivacaine group compared to the bupivacaine group (P < 0.001).

Conclusions

Ropivacaine reduces the incidence of hypotension in spinal anesthesia compared to bupivacaine for cesarean section in patients with preeclampsia. This is attributed to a lower occurrence of spinal-induced hypotension, improved hemodynamic control, reduced ephedrine usage, and faster patient ambulation. A future study could focus on investigating different dosages of both drugs with a larger number of participants.

Physicochemical Stability Study of the Morphine-Bupivacaine-Ziconotide Association

OBJECTIVE

The aim of this study was to investigate the physicochemical stability of morphine-bupivacaine-ziconotide mixtures used in intrathecal analgesia in polypropylene syringes and intrathecal pumps.

MATERIALS AND METHODS

The stability study method was conceived according to International Council for Harmonisation guidelines. For propylene syringes, six different mixtures of morphine-bupivacaine and ziconotide were assessed over seven days. Two storage temperatures were tested (5 °C ± 3 °C and 25 °C ± 2 °C). For implantable pumps, nine different mixtures were assessed over 60 days and stored at 37 °C. Assays were performed using ultrahigh-pressure liquid chromatography. Turbidity and pH also were measured throughout the study.

RESULTS

Results confirmed excellent physicochemical stability for morphine and bupivacaine in the study for all conditions investigated (pumps at 37 °C, polypropylene syringes at 5 °C ± 3 °C and 25 °C ± 2 °C). Concerning ziconotide, after seven days, our study showed that every 95% confidence interval calculated had lower bounds >90% for all mixtures stored in polypropylene syringes. In implantable pumps, a decrease of the concentration was observed in all the mixtures studied. Moreover, the appearance of a degradation product confirmed the ziconotide degradation.

CONCLUSION

All results are in favor with a physicochemical stable preparation for six mixture profiles when stored in polypropylene syringes at 5 °C ± 3 °C and 25 °C ± 2 °C. For mixtures stored in implantable pumps, the efficacy should decrease over time owing to the degradation of ziconotide. A trade-off between high morphine concentration and increased refill interval will need to be found by clinicians.

Crocin alleviates neurotoxicity induced by bupivacaine in SH-SY5Y cells with inhibition of PI3K/AKT signaling

BACKGROUND

Bupivacaine, a common local anesthetic, can cause neurotoxicity and permanent neurological disorders. Crocin has been widely reported as a potential neuroprotective agent in neural injury models.

OBJECTIVE

The aim of this study was to investigate the role and regulatory mechanism of crocin underlying bupivacaine-induced neurotoxicity.

METHOD

Human neuroblastoma SH-SY5Y cells were treated with bupivacaine and/or crocin for 24 h, followed by detecting cell viability using 3-(4,5-dimethylthiazol-2-yl)-2, 5-diphenyltetrazolium bromide assay. The effect of crocin or bupivacaine on SH-SY5Y cell proliferation was measured by Ki67 immunofluorescence assay. The levels of apoptosis-related proteins and the markers in the PI3K/Akt signaling pathway were examined using western blot analysis. The activities of caspase 3, catalase (CAT), superoxide dismutase (SOD), malondialdehyde (MDA) and glutathione peroxidase (GSH-Px) were tested using respective commercial assay kits. Flow cytometry analysis was executed for detecting SH-SY5Y cell apoptosis.

RESULT

Crocin attenuated bupivacaine-induced neurotoxicity in SH-SY5Y cells. Meanwhile, crocin inhibited SH-SY5Y cell apoptosis induced by bupivacaine via repressing the activity of caspase-3, reducing Bax expression, and elevating Bcl-2 expression. Moreover, crocin mitigated oxidative stress in SH-SY5Y cells by increasing the content of CAT, SOD, GSH-Px and reducing the content of MDA. Additionally, crocin protected against bupivacaine-induced dephosphorylation of Akt and GSK-3β. The protective effects of crocin against bupivacaine-induced neurotoxicity in SH-SY5Y cells were counteracted by the Akt inhibitor.

CONCLUSION

These results suggested that crocin may exert a neuroprotective function by promoting cell proliferation and suppressing apoptosis and oxidative stress in SH-SY5Y cells. Thus, crocin might become a promising drug for the treatment of bupivacaine-induced neurotoxicity.

Is transoral sphenopalatine ganglion blockade more effective on postoperative pain than endoscopic sphenopalatine ganglion blockade?

PURPOSE

In this study, we aimed to examine and compare the effects of endoscopic SPGB and transoral SPGB on postoperative pain control and patient satisfaction in patients undergoing septoplasty.

METHODS

Participants were randomly divided into three groups, no blockade (n:20), endoscopic SPGB (n:20), and transoral SPGB (n:20). Those who had no blockage were included in the control group. Demographic data of patients, such as age and sex, VAS (visual analogue scale) and postoperative pain scores (PPS) [determined at arrival in the post-anesthesia care unit (PACU) and after 2, 6, 12, and 24 h], general analgesic use (24 and 168 h after surgery) and postoperative Quality of Recovery (QoR-15) values were recorded and compare them.

RESULTS

The PPS PACU of 2 h, 6 h, 12 h, and 24-h values of the transoral group were lower than the endoscopic and control groups (p < 0.001).The values of 24 h and 168 h of analgesic use in the transoral group were lower than in the control and endoscopic groups (p < 0.001).The average recovery QoR-15 scores at 12 h and 24 h differed according to the groups (p < 0.001) and the highest values were in the transoral group (p < 0.001).

CONCLUSION

Transoral SPGB is more effective in postoperative pain control than endoscopic SPGB, it decreases the use of postoperative analgesics and improves postoperative recovery scores.

The comparison of the analgesic efficacy of continuous paravertebral block alone compared with continuous paravertebral and intercostal nerve block for thoracotomy in adults: a randomized controlled trial

PURPOSE

The study aims to compare the analgesic efficacy of two analgesic interventions, continuous paravertebral (PVB) nerve block alone with continuous paravertebral and intercostal nerve block (PVB/ICB) in patients undergoing thoracotomy.

METHODS

A total of 70 patients undergoing thoracotomy were randomly enrolled in either continuous paravertebral nerve block (PVB) group or in continuous paravertebral and intercostal nerve block (PVB/ICB) group and received corresponding blocks. Analgesic efficacy measured by Visual Analog Scale (VAS) pain score, hemodynamic effects, total narcotic consumption, sedation score, patient's length of stay in hospital and patient's satisfaction with the analgesic technique were recorded.

RESULTS

Demographic characteristics of the patients were similar in both groups. The mean VAS pain score was not statistically significant in both groups at 24 h. The mean pulse rate and blood pressures were comparable in both groups for the first 24 h. Nalbuphine consumption was significantly higher in PVB group as compared to PVB/ICB group at 1 h (p = 0.01), 6 h (p = 0.03) and 12 h (p = 0.009) and 24 h (p = 0.03). The mean total nalbuphine consumption in the PVB group was higher (28.29 mg vs. 22.63 mg) and statistically significant then PVB/ICB group (p = 0.03). The total tramadol consumption as a rescue analgesic was higher in the PVB group (131.42 mg) as compared to PVB/ICB group (120 mg) after 24 h but not statistically significant (p = 0.17).

CONCLUSION

Continuous paravertebral nerve block with intercostal nerve block provides effective post-operative pain relief after thoracotomy with reduced narcotic consumption compared to continuous paravertebral nerve block alone.

CLINICAL TRIAL REGISTRATION NUMBER

Clinicaltrails.gov NCT04715880.

The effect of local injection of bupivacaine with and without fentanyl at the operative site in mandibular open reduction on acute pain intensity and opioid requirement: a randomized clinical trial

PURPOSE

The aim of this study is to investigate the effects of bupivacaine local injection with and without fentanyl at the operative site in mandibular open reduction surgeries on the severity of acute pain and the need for opioids.

METHODS

This randomized clinical trial, age-sex-matched double-blind study included 44 patients with isolated mandibular fractures who would be candidates for open reduction. They were divided into two groups (intervention using fentanyl and control not using fentanyl). In both groups, the amount of opioid used, hemodynamic indices, oxygen saturation, and pain intensity were collected based on the Visual Analogue Scale (VAS) every 4 h for 24 h.

RESULTS

As for basic and demographic variables such as gender, age, ASA class, and duration of surgery (P > 0.05), there was neither a significant difference between the two groups nor was there any difference in nausea and vomiting and subsequent anti-nausea medication (P > 0.05). The need for a post-operative opioid in the bupivacaine + fentanyl group (13.6%) was significantly less than in those who received only bupivacaine (45.5%) (P < 0.05). Changes in pain scores over time were significantly different in the two groups, and bupivacaine + fentanyl reduced pain more than bupivacaine (P < 0.05). However, over time, there was no significant difference between the two groups in terms of changes in oxygen saturation, heart rate, systolic blood pressure, and diastolic blood pressure (P > 0.05).

CONCLUSION

The addition of fentanyl to bupivacaine for supraperiosteal injection in the open reduction surgery site reduces post-operative pain in the first 24 h and reduces the need for opioids without causing complications such as nausea and vomiting.

Efficacy of lidocaine vs combination of lidocaine and bupivacaine in management of maxillofacial trauma: a clinical comparative study

BACKGROUND

The COVID-19 pandemic has created an unprecedented situation which the treatment of maxillofacial trauma, especially mandibular fractures that were previously managed using general anaesthesia had to be performed under local anaesthesia. In these cases, there was a requirement for an anaesthetic agent that would have a rapid onset but also provide a prolonged effect. The aim of the study was to evaluate the onset, duration, depth, required volume of anaesthesia of lidocaine with epinephrine versus combination of lidocaine and bupivacaine with epinephrine anaesthetic agents in surgical management of isolated mandibular fracture patients.

METHODS

A total of 30 patients with isolated mandibular fractures reported to our hospital included the study group. Patients were randomly distributed to two groups, Group A and Group B. Group A received local anaesthesia using 2% Lidocaine with 1:80,000 adrenaline and Group B received 0.5% Bupivacaine with 1:2,00,000 adrenaline combined with 2% Lidocaine with 1:80,000 adrenaline at a ratio of 1:1. The outcome variables were recorded and the data was tabulated and analysed using un-paired students t test.

RESULTS

The combination of anaesthetic agents had longer duration of action (mean: 182.47 min, P-value: 0.001) and required lesser volume of anaesthetic solutions (mean: 5.38 mL, P-value: 0.001) as compared to usage of lidocaine alone. Although combination group showed quicker onset (mean: 4 min 8 s), the result was insignificant (p-value: 0.345).

CONCLUSION

The study found that the combination of lidocaine and bupivacaine could serve as a potential anaesthetic cocktail in effective surgical management of isolated mandibular fractures.

CLINICAL RELEVANCE

Maxillofacial injuries can be managed efficiently under local anaesthesia using combination of lidocaine and bupivacaine.

Dexmedetomidine versus sufentanil as adjuvants to bupivacaine for brachial plexus block during upper extremity surgery: a randomized clinical trial

BACKGROUND

Brachial plexus block (BPB) has been accepted as a reliable alternative for general anesthesia in upper limb surgeries. Adding adjuvant drugs like dexmedetomidine and sufentanil has been shown to have clinical and pharmacologic advantages. In this randomized parallel clinical trial, we aim to compare the effects of these two adjuvants for bupivacaine in BPB.

METHODS

In this double-blinded study, by using computer-assisted block randomization, 40 patients ranged from 20 to 65 years old and scheduled for elective upper limb surgeries were assigned to two equal study groups (n = 20), receiving 1 mL of 5 ..g.mL-1 sufentanil (group S) or 1 mL of 100 ..g.mL-1 dexmedetomidine (group D) in adjunction to 30 mL of 0.5% bupivacaine for supraclavicular BPB under the guidance of ultrasonography. Characteristics of local anesthesia and postoperative analgesia were evaluated (n = 40).

RESULTS

The duration of blocks significantly improved in group S (sensory: estimated median difference (EMD) [95%CI] = 100.0 [70.0...130.0], p < 0.001; motor: EMD [95%CI] = 120.0 [100.0...130.0], p < 0.001). Group S also had significantly longer postoperative analgesia and lower opioid consumption within 24 hours after the surgery (EMD [95%CI] = 4.0 [3.0...7.0], p < 0.001; EMD [95%CI] = -5.0 [-5.0...-5.0], p < 0.001; respectively). None of the patients showed adverse effects concerning vital signs, nausea, or vomiting.

CONCLUSION

Our study showed that during ultrasound-guided supraclavicular BPB, sufentanil is a fairly better choice than dexmedetomidine as an adjuvant for bupivacaine and can provide preferable sensory and motor blocks. No significant side effects were seen in either of the study groups.

Comparing spinal anesthesia approaches for transurethral lithotripsy in patients with proximal ureteral stones: A randomized clinical trial of bupivacaine alone versus bupivacaine with fentanyl

Despite the benefits of spinal anesthesia and the preference of anesthesiologists for this technique, it is less accepted by urologists due to the proximity of the stone place in the ureter and the possibility of pain, restlessness, and occasional movements of the patient during surgery. The current study investigated the success of bupivacaine plus intrathecal fentanyl in patients undergoing transurethral lithotripsy (TUL). In this randomized clinical trial, from April 2021 to September 2021, 54 patients with proximal urolithiasis candidates for TUL were enrolled. Patients were randomly categorized into two groups: group A received bupivacaine 10 mg and 0.5 ml of normal saline, while group B received bupivacaine 10 mg with 0.5 ml (25µg) of intrathecal fentanyl. According to our findings, about 74% of the patients were men, and the mean age of the patients was 66.14±22.46 years. The onset time of the sensory block, sensory block level, pain score, degree of relaxation, depth of the motor block, occurrence of anesthesia complications, oxygen saturation, and mean arterial blood pressure were not significantly different between the two groups. However, the duration of the motor block in group B was longer than in group A (p<0.001). Also, retropulsion was observed only in five patients (18.5%) in group A, significantly higher than in group B (p=0.019). Bupivacaine with fentanyl 25µg provided adequate spinal anesthesia with lower retropulsion in patients with urolithiasis who are candidates for TUL.

Local anaesthetic for pain post rubber band ligation of haemorrhoids: a prospective, single-blinded randomised controlled trial

BACKGROUND

Rubber band ligation (RBL) is a widely accepted intervention for the treatment of haemorrhoids. However, post procedure pain is a common complaint. The aim of this study was to determine whether the addition of local anaesthetic (LA) to the haemorrhoid pedicle base, post RBL, aids in reducing early post-procedure pain. Additionally, to compare perceived perianal numbness, oral analgesia usage and total consumption, and adverse events.

METHODS

This study was a prospective, single-blinded randomised controlled trial. Patients were recruited from colorectal clinics in two Australian hospitals between 2018-2019. Patients randomised to the intervention (LA) group received 2mls bupivacaine 0.5% with adrenaline 1:200,000 to each haemorrhoid base. Patients in the control group were not administered LA. Pain scores were recorded over 48 h using visual analogue scales. Analgesia consumption was documented and other secondary objectives were recorded dichotomously (yes/no).

RESULTS

At 1 h post-procedure, patient reported pain scores were significantly lower in the LA group compared to the control group (p = 0.04). There were no significant differences in pain scores between the groups at 4, 24 or 48 h. Additionally, there were no significant differences between groups with respect to oral analgesia usage, perianal numbness or adverse events.

CONCLUSIONS

LA to the haemorrhoid pedicle post RBL may significantly reduce early post procedure pain without any increased risk of adverse effects.

Ultrasound-guided trans-incisional quadratus lumborum block versus ultrasound-guided caudal analgesia in pediatric open renal surgery: a randomized trial

BACKGROUND

The caudal route is a common approach for postoperative analgesia; however, it is associated with limited duration of action. The quadratus lumborum block (QLB) may produce prolonged postoperative analgesia. Therefore, this study aimed to compare the postoperative analgesic efficacy of the ultrasound-guided caudal block with that of the ultrasound-guided transincisional QLB (TiQLB) in pediatric patients undergoing open renal surgery.

METHODS

Forty patients of both sexes, aged 2-11 years, were randomly assigned to receive either caudal analgesia with 1.25 ml/kg of bupivacaine 0.2% (Caudal group; n = 20) or a QLB with 0.5 ml/kg of bupivacaine 0.2% (TiQLB group; n = 20) in addition to standard general anesthesia. Time to first analgesia was the primary outcome. Total analgesic consumption in the first 24 h postoperatively, pain scores, and the incidence of side effects were the secondary outcomes.

RESULTS

The mean time to first analgesic requirement was significantly longer in the TiQLB group than in the Caudal group (18.8 ± 5.1 vs. 6.7 ± 0.7 h, P < 0.001). Total ketorolac consumption and pain scores were significantly lower in the TiQLB group (P < 0.001). A few cases of mild postoperative nausea and vomiting were noted among patients in both groups; however, the difference was not statistically significant. No incidence of pruritus, shivering, or respiratory depression was noted.

CONCLUSIONS

Analgesia after the ultrasound-guided TiQLB with bupivacaine was superior to that after the ultrasound-guided caudal block, with similar side effects.

Pain Management and Opioid Use with Long-Acting Peripheral Nerve Blocks for Hand Surgery: A Descriptive Study

Background

Peripheral nerve blocks (PNBs) are used in multiple surgical fields to provide a high level of regional pain relief with a favorable adverse effect profile. Peripheral nerve blocks aim to decrease overall perioperative pain and lower systemic analgesic requirements. Short-acting anesthetic agents are commonly given as single-injection PNBs for pain relief, typically lasting less than 24 hours. Liposomal bupivacaine is a newer anesthetic formulation lasting up to 72 hours as a single-injection PNB and may allow patients to recover postoperatively with a lower need for opioid analgesics.

Objectives

This study investigates peri- and postoperative pain and opioid use in patients receiving a long-acting brachial plexus PNB for hand surgery.

Methods

A retrospective review of patients who underwent a long-acting PNB using liposomal bupivacaine in the brachial plexus for minor hand operations was performed between July 2020 and May 2023 in Florida, USA. Patients were administered a ten-question survey regarding perioperative pain levels, post-operative symptoms, patient satisfaction, postoperative opioid use, and postoperative non-opioid analgesics.

Results

One hundred three patients, including 21 males and 82 females with an average age of 68.3 ± 15.8 years, completed a survey (34.2% response rate). Patients reported a considerable reduction in pain from 7.9 ± 2.2 out of ten before the PNB to 1.6 ± 1.8 in the perioperative period, 4.3 ± 2.7 in postoperative days zero to three, and 3.8 ± 2.4 in postoperative days four and five. Nerve block effects lasted a mean of 2.2 ± 2.0 days and patients reported a high level of satisfaction regarding their pain management plan with a score of 9.4 ± 1.4 out of ten. 20.4% of patients were prescribed opioids and 41.7% used NSAIDs postoperatively.

Conclusions

Liposomal bupivacaine PNBs effectively reduced peri- and postoperative pain with pain relief lasting 2.2 ± 2.0 days. Patients were highly satisfied with their pain management and there was a low rate of postoperative opioid prescription. Given these results, long-acting PNBs have the potential to significantly improve patient satisfaction, reduce anesthesia use, and reduce postoperative opioid prescription.

Does local infiltration analgesia in total joint arthroplasty offer any protection from prosthetic joint infections? An invitro experimental study

Many local anaesthetic agents are now reported to have anti-microbial properties in various studies, and this ability to inhibit microbial growth is not uniform. As local anaesthetics are commonly infiltrated into the surgical field for perioperative pain management, it is very important to know if this practice offers any protection against surgical site infections.

METHODS

In this study, three of the most common prosthetic joint infection-causing organisms, namely, Staphylococcus aureus, Staphylococcus epidermidis and Escherichia coli, were chosen and tested against the commonly used local anaesthetics. The suspension of each organism was inoculated onto three different Mueller-Hinton agar plates and a drop of an undiluted solution of each local anaesthetic agent is inoculated onto one of the three culture plates; vancomycin and gentamicin discs were used as controls.

RESULTS

The local anaesthetic agents tested could not inhibit the growth of any of the microorganisms. As there was no inhibition of bacterial growth in the experiment with the above three agents, further experiment with a diluted mixture was not performed.

CONCLUSIONS

It can be concluded that local infiltration of anaesthetic agents is less likely to provide any perioperative protection against prosthetic joint infections but may interfere with some diagnostic tests for microbiology.

Effect of intravenous dexamethasone on the duration of hyperbaric bupivacaine spinal anesthesia in lower abdominal surgery, Randomized controlled trial

BACKGROUND

The purpose of this study was to investigate the effect of intravenous (IV) dexamethasone on the duration of hyperbaric bupivacaine spinal anesthesia.

METHODS

Two hundred patients between the ages of 18 and 60, of both sexes with ASA I- II classification scheduled for lower abdominal surgery under spinal anesthesia using hyperbaric bupivacaine 0.5% were randomly divided into two groups: the dexamethasone group (Dexa group) and the control group, with 100 patients in each group. Before the administration of spinal anesthesia, the Dexa group received an intravenous infusion of 8 mg dexamethasone in 500 mL normal saline, while the control group received 500 mL normal saline only. The primary outcome of this study was to assess the effect of IV dexamethasone on the regression of hyperbaric bupivacaine spinal anesthesia. Secondary outcome measures included the total duration of sensory and motor blocks, VAS score, time of first analgesic request, total analgesic consumption within the first 24 h, and the occurrence of any side effects.

RESULTS

The Dexa group had significantly delayed onset of 2 dermatomes regression (P < 0.001) compared to the control group. Additionally, the Dexa group had significantly longer duration of both sensory block (P = 0.01) and motor block (P < 0.001). The Dexa group had significantly longer duration until the first postoperative analgesic request (P < 0.001) and a lower incidence of side effects compared to the control group.

CONCLUSION

Although the intravenous administration of dexamethasone had a limited effect on the duration of hyperbaric bupivacaine spinal anesthesia, it improved postoperative VAS scores compared to the control group and decreased overall postoperative analgesic consumption. Therefore, it can be considered a valuable addition to postoperative multimodal analgesia strategies, aiming to minimize total analgesic consumption.

CLINICAL TRIAL REGISTRATION

ID: NCT04778189 (2/3/2021).

In vitro elution of local anesthetics from PMMA bone cement

BACKGROUND AND AIM

Currently, we do not have a gold standard for pain management after total knee arthroplasty. We may use one of more drug delivery systems, none of which are ideal. An ideal depot delivery system would provide therapeutic, nontoxic, doses of drug at the surgical side, especially during 72h postoperatively. The bone cement used in arthroplasties has been used as a drug delivery system, especially antibiotics, since 1970. Based on this principle, we developed this study with the aim to characterize the elution profile of two local anesthetics (lidocaine hydrochloride and bupivacaine hydrochloride) from PMMA (polymethilmethacrylate) bone cement.

MATERIAL AND METHODS

Palacos® R+G bone cement and lidocaine hydrochloride or bupivacaine hydrochloride specimens were obtained depending on the study group. These specimens were immersed in PBS (phosphate buffered saline) and removed from the solution at different set times. Subsequently, the concentration of local anesthetic in the liquid was analyzed by liquid chromatography.

RESULTS

The percentage of lidocaine eluted from PMMA bone cement in this study was 9.74% of the total lidocaine content per specimen at 72h and 18.73% at 336h (14 days). In case of bupivacaine, the elution percentage was 2.71% of the total bupivacaine content per specimen at 72h and 2.70% at 336h (14 days).

CONCLUSIONS

Local anesthetics elute in vitro from PMMA bone cement, reaching doses at 72h close to the doses used in anesthetic blocks.

Comparison between bupivacaine injection and mini-tenotomy in the management of horizontal small angle strabismus in children

PURPOSE

To compare the outcome of bupivacaine (BUP) injection vs mini-tenotomy of extra-ocular muscles in treating small angle horizontal strabismus in children.

METHODS

A prospective comparative study that included a total of 40 patients. Twenty patients received 3 ml of 0.75% Bupivacaine (BUP) injection in both medial recti in case of exotropia and in both lateral recti in case of esotropia. MRI orbit was performed before and 30-60 days' post injection of bupivacaine to estimate changes in muscle size. Mini-tenotomy was done in the other 20 patients, performed on both lateral recti in case of exotropia and on both medial recti in case of esotropia.

RESULTS

Mean change of alignment at the end of 6 months in exotropic patients in bupivacaine group was 5.50 ± 4.10 PD and in esotropia patients 4.00 ± 3.38 PD with an average increase in muscle thickness of 0.12 mm ± 0.08 and 0.13 mm ± 0.09 in exotropia and esotropia, respectively. There was an average increase in volume 23 mm3 ± 17.3 and 17.00 mm3 ± 9.50 in exotropia and esotropia, respectively, as measured with MRI. The mean change of alignment in mini-tenotomy was 5.33 ± 4.12 PD, 5.75 ± 4.95 PD in exotropia and esotropia, respectively.

CONCLUSION

Bupivacaine and mini-tenotomy are safe and effective alternative treatment, that improved eye alignment in 65% of patients with small angle horizontal deviation.

[Translated article] In vitro elution of local anaesthetics from PMMA bone cement

BACKGROUND AND AIM

Currently, we do not have a gold standard for pain management after total knee arthroplasty. We may use one of more drug delivery systems, none of which are ideal. An ideal depot delivery system would provide therapeutic, nontoxic, doses of drug at the surgical side, especially during 72h postoperatively. The bone cement used in arthroplasties has been used as a drug delivery system, especially antibiotics, since 1970. Based on this principle, we developed this study with the aim to characterise the elution profile of two local anaesthetics (lidocaine hydrochloride and bupivacaine hydrochloride) from PMMA (polymethilmethacrylate) bone cement.

MATERIAL AND METHODS

Palacos® R+G bone cement and lidocaine hydrochloride or bupivacaine hydrochloride specimens were obtained depending on the study group. These specimens were immersed in PBS (phosphate buffered saline) and removed from the solution at different set times. Subsequently, the concentration of local anaesthetic in the liquid was analysed by liquid chromatography.

RESULTS

The percentage of lidocaine eluted from PMMA bone cement in this study was 9.74% of the total lidocaine content per specimen at 72h and 18.73% at 336h (14 days). In case of bupivacaine, the elution percentage was 2.71% of the total bupivacaine content per specimen at 72h and 2.70% at 336h (14 days).

CONCLUSIONS

Local anaesthetics elute in vitro from PMMA bone cement, reaching doses at 72h close to the doses used in anaesthetic blocks.

Comparison of Mean Post-Operative Pain Score with Pre-Incisional Versus Postoperative Injection of Bupivacaine in Patients Undergoing Elective Surgery

The most important concern after the surgical intervention is pain which needs to be addressed for better compliance and early mobilization to avoid other complications. The need for a better analgesic and time of administration is the key to success.

Objective

To compare the mean post-operative pain score with pre-incisional versus post-operative injection of bupivacaine in patients undergoing elective surgery.

Study design

This Randomized controlled trial was conducted in the General surgery department, National Hospital & Medical Centre, Lahore from 24-02-20 to 24-11-20. Data was collected through Non-probability consecutive sampling. The cases of both genders with an age range of 18-60 years undergoing elective surgeries were selected. They were divided into two groups. The cases in group A were given pre-incision bupivacaine and group B with post-operative bupivacaine and were assessed 1 hour after surgery regarding pain on VAS.

Results

In the present study there were a total of 64 cases with 32 in each group. The mean age in group A was 47.56±7.51 years while in group B was 49.13±8.03 years. There were 19 (59.37%) males in group A vs 18 (56.25%) in group B. The mean post-operative pain in group A was 3.07±0.67 vs 3.59±0.91 in group B on VAS with p= 0.03. Mean post-operative pain in males was 3.12±0.65 vs 3.47±0.86 and in females, it was 3.21±0.66 vs 3.53±0.90 in groups A and B with p values of 0.21 and 0.23 respectively. Mean Post-operative pain was 3.11±0.66 vs 3.44±0.83 in the age group 18-39 years and 3.08±0.68 vs 3.47±0.88 in age group 40 to 60 years in group A and B with p values of 0.25 and 0.20 respectively. There was a significant difference in terms of postoperative pain in cases undergoing open cholecystectomy where pain was 3.21±0.78 vs 3.86±1.02 in group A and B respectively with p= 0.01. Whereas no difference was seen in the rest of the variables.

Conclusion

Mean post-operative pain is significantly better in cases treated with pre-incisional bupivacaine as compared to post-operative bupivacaine and this difference was also seen as significantly high in cases undergoing open cholecystectomy.

Ferrostatin-1 ameliorates Bupivacaine-Induced spinal neurotoxicity in rats by inhibiting ferroptosis

Bupivacaine (BUP) has previously been shown to trigger neurotoxicity after spinal anesthesia. Further, ferroptosis has been implicated in the pathological processes associated with various central nervous system diseases. Although the impact of ferroptosis on BUP-induced neurotoxicity in the spinal cord has not been fully understood, this research aims to investigate this relationship in rats. Additionally, this study aims to determine whether ferrostatin-1 (Fer-1), a potent inhibitor of ferroptosis, can provide protection against BUP-induced spinal neurotoxicity. The experimental model for BUP-induced spinal neurotoxicity involved the administration of 5% bupivacaine through intrathecal injection. Then, the rats were randomized into the Control, BUP, BUP + Fer-1, and Fer-1 groups. BBB scores, %MPE of TFL, and H&E and Nissl stainings showed that intrathecal Fer-1 administration improved functional recovery, histological outcomes, and neural survival in BUP-treated rats. Moreover, Fer-1 has been found to alleviate the BUP-induced alterations related to ferroptosis, such as mitochondrial shrinkage and disruption of cristae, while also reducing the levels of malondialdehyde (MDA), iron, and 4-hydroxynonenal (4HNE). Fer-1 also inhibits the accumulation of reactive oxygen species (ROS) and restores the normal levels of glutathione peroxidase 4 (GPX4), cystine/glutamate transporter (xCT), and glutathione (GSH). Furthermore, double-immunofluorescence staining revealed that GPX4 is primarily localized in the neurons instead of microglia or astroglia in the spinal cord. In summary, we demonstrated that ferroptosis play a pivotal role in mediating BUP-induced spinal neurotoxicity, and Fer-1 ameliorated BUP-induced spinal neurotoxicity by reversing the underlying ferroptosis-related changes in rats.

Ropivacaine on Maternal and Neonatal Outcomes After Cesarean Section: A Systematic Review and Meta-analysis

Context

The type of anesthesia in cesarean section can affect the mother and baby. This study aimed to determine the comparative effect of intrathecal hyperbaric bupivacaine vs. hyperbaric ropivacaine on maternal and neonatal outcomes after cesarean section.

Evidence Acquisition

PubMed, Web of Science, Embase, Google Scholar, IranDoc, MagIran, and Scopus databases were searched from 1 September 2022 to 1 November 2022. Eighteen clinical trials with 1542 patients were included in the analysis.

Results

There was no statistically significant difference in hypotension, bradycardia, and Apgar score between the 2 groups (P > 0.05). The risk of nausea (relative risk (RR), 1.526; 95% CI, 1.175 - 1.981; P = 0.001) and vomiting (RR, 1.542; 95% CI, 1.048 - 2.268; P = 0.02) caused by bupivacaine was 0.53% and 0.54% higher than that of ropivacaine. The incidence of shivering (RR, 2.24; 95% CI, 1.480 - 3.39; P = 0.00) was 2.24 times higher in the bupivacaine group than in the ropivacaine group. The average onset time of sensory block (standardized mean difference (SMD), -0.550; 95% CI, -1.054 to -0.045; P = 0.032) and motor block (SMD, -0.812; 95% CI, -1.254 to -0.371; P = 0.000) was significantly lower in the bupivacaine group than in the ropivacaine group.

Conclusions

Despite the fact that ropivacaine and bupivacaine are effective in cesarean section, ropivacaine is more favorable because of less hemodynamic changes, less duration of sensory and motor block, and fewer side effects, which are effective in patient recovery.

Anesthesia characteristic of an algorithm of bupivacaine dose based on height in caesarean section under spinal anesthesia: a retrospective cohort study

BACKGROUND

An algorithm of bupivacaine dose based on height is applied to reduce maternal hypotension in caesarean section under spinal anesthesia. This study is designed to further verify whether the algorithm of bupivacaine dose based on height is suitable.

METHODS

The parturients were grouped according to height. The comparison of anesthesia characteristic among subgroups was carried out. The univariate and multivariate binary logistic regressions were executed to reanalyze the interference factor for the anesthesia characteristic.

RESULTS

When the dose of bupivacaine was adjusted by using the height based dosing algorithm, except for weight (P < 0.05), other general data did not present statistical changes with height (P > 0.05); the incidences of complications, characteristics of sensory or motor block, quality of anesthesia and neonatal outcome were of no statistical difference among parturients with different heights (P > 0.05); the height, weight and body mass index were not related with maternal hypotension (P > 0.05). When the dose of bupivacaine is constant, except for weight and body mass index (P > 0.05), the height was the independent risk factor for maternal hypotension (P < 0.05).

CONCLUSIONS

Except for weight and body mass index, the height has an influence on the bupivacaine dose. It is reasonable that the bupivacaine dose is adjusted by using this dosing algorithm based on height.

TRIAL REGISTRATION

This study was registered at http://clinicaltrials.gov (13/04/2018, NCT03497364).

Evaluation of efficacy of peribulbar block with the combination of 2% lidocaine and 0.5% bupivacaine in comparison with 2% lidocaine and 0.75% ropivacaine in cataract surgery

Introduction

Cataract surgery is performed under peribulbar or retrobulbar block. Majority of the patients posted for cataract have some form of medical diseases like diabetes, hypertension, angina, ischaemic heart disease etc. Lidocaine and bupivacaine are the most commonly used local anesthetic for the block procedure. Here we compare the efficacy of peribulbar block in cataract surgery using the combination of 1:1 mixture of 2% lidocaine with 0.5% bupivacaine and 1:1 mixture of 2% lidocaine with 0.75% ropivacaine.

Materials and Methods

It is a prospective, randomized, double blinded study including 60 patients were devided into two groups of 30 each, Group-R received 8 ml of 1:1 mixture of 4 ml of 2% lidocaine, 4 ml of 0.75% ropivacaine and 15 IU/ml of hyaluronidase and group-B received 8 ml of 1:1 mixture of 4 ml of 2% lidocaine, 4 ml of 0. 5% bubivacaineand 15 IU/ml of hyaluronidase. Peribulbar block was performed as per Bloomberg's modification of the Davis and Mandel technique where 5 ml of local anesthetic was injected in the infero temporal region and 3 ml of drug was injected in the superi nasal area. Patients were assessed for sensory block, eyelid and occular movements at an interval of 2 minutes. Systolic, diastolic and mean arterial pressures, heart rate, oxygen saturation, ECG were monitored non invasively at 1,3,5,8,10,15 and then every 10 minutes till the end of the surgery.

Observation and Discussion

Mean time for the onset of sensory blockade was 2.70 ± 6.5 minutes in Group B and 2.63 ± 0.57 minutes in group R with P-value 0.671, showing no significant difference in the onset of sensory blockade. Onset of motor blockade was 6.53 ± 1.81 minutes in group B, and 7.57 ± 1.46 minutes in the group R, the P-value being 0.018 was statistically significant. Regarding the duration of analgesia, our study showed mean time for analgesia lasted for 295 ± 54.63 minutes in group B and 414.67 ± 99.47 in group R with P value 0.001 showing statistically significant prolongation of duration of analgesia with group R. We observed a significant increase of mean IOP in bupivacaine group from 13.333 ± 1.582 mm Hg to 21.966 ± 2.697 mm Hg, whereas in ropivacaine group it increased from 12.766 ± 1.222 mm Hg to 13.0 ± 1.341 mm Hg after peribulbar anaesthesia.

Characterization of Exparel Bupivacaine Multivesicular Liposomes

Exparel is a bupivacaine multivesicular liposomes (MVLs) formulation developed based on the DepoFoam technology. The complex composition and the unique structure of MVLs pose challenges to the development and assessment of generic versions. In the present work, we developed a panel of analytical methods to characterize Exparel with respect to particle size, drug and lipid content, residual solvents, and pH. In addition, an accelerated in vitro drug release assay was developed using a rotator-facilitated, sample-and-separate experimental setup. The proposed method could achieve over 80% of bupivacaine release within 24 hours, which could potentially be used for formulation comparison and quality control purposes. The batch-to-batch variability of Exparel was examined by the established analytical methods. Four different batches of Exparel showed good batch-to-batch consistency in drug content, particle size, pH, and in vitro drug release kinetics. However, slight variation in lipid contents were observed.

Evaluation of the effects of bupivacaine combined with sugammadex on the duration of the nociceptive blockade in sciatic nerve blocks: a controlled, double-blind animal study

BACKGROUND

Animal and other experimental studies have demonstrated increased block time and quality when α- and β-cyclodextrin drugs are combined with local anesthetics. However, to our knowledge, no study has utilized γ-cyclodextrins in such a combination. In the present study, we used an animal model to evaluate the effects of different doses of the combined administration of γ-cyclodextrin (sugammadex) and bupivacaine on the duration of sciatic nerve blocks in rats.

METHODS

Sciatic nerve blocks were performed with a 0.20 ml mixture in all groups. For the non-experimental groups, this mixture consisted of 0.2 ml saline (Sham group), 0.2 ml sugammadex (Group S), or 0.16 ml bupivacaine 0.5% and 0.04 ml saline (Group B). For the experimental groups, 0.16 ml bupivacaine 0.5% was administered along with 0.01 ml sugammadex and 0.03 ml saline (Group BS1), 0.02 ml sugammadex and 0.02 ml saline (Group BS2), or 0.04 ml sugammadex (Group BS4). Proprioception, nociception, and motor function were evaluated until the sciatic block was completely reversed.

RESULTS

Motor, proprioceptive, and nociceptive blockades occurred within 5 min in all experimental groups. In Group BS4, the duration of the motor, proprioceptive, and nociceptive blockades was significantly increased compared with the other experimental groups. However, in Groups BS1 and BS2, only the duration of the nociceptive blockade was significantly increased.

CONCLUSIONS

The combined administration of sugammadex and bupivacaine for sciatic nerve blocks in rats led to a significant increase in the duration of motor, proprioceptive, and nociceptive blockades.

Comparison of Epidural Bupivacaine and Buprenorphine to Bupivacaine and Butorphanol for Postoperative Analgesia in Lower Limb Orthopedic Surgery

Background

Postoperative analgesia is of utmost importance in the treatment of patients undergoing surgery. Good postoperative pain management reduces hospital stay and improves early ambulation. This study compared the efficacy of epidural bupivacaine with buprenorphine to butorphanol in lower limb orthopedic surgery.

Objectives

This study was carried out to investigate the onset of analgesia, the extent of analgesia, sedation score, and side effects of butorphanol with bupivacaine versus buprenorphine with bupivacaine.

Methods

In a clinical trial study, 100 patients who underwent elective orthopedic lower limb surgery were randomly allocated to two groups. A total of 100 patients with American Society of anesthesiologists grades I and II posted for lower limb orthopedic surgery were enrolled in this randomized, double-blind study. The patients were divided into groups A and B. Subarachnoid block was achieved with 3.4 mL of 0.5% bupivacaine. The pain was monitored by the visual analog scale postoperatively. The patients in group A received bupivacaine with buprenorphine, and group B received bupivacaine with butorphanol when they complained of pain in the postoperative period. The onset of analgesia, duration of analgesia, sedation score, and side effects were compared between the two groups.

Results

The onset of analgesia was observed earlier in group A than in group B (7.7 ± 1.6 vs. 12.6 ± 1.7 minutes, P < 0.001). The duration of analgesia was longer in group A than in group B (590 ± 40 vs. 480 ± 54 minutes, P < 0.001). Pulse rates and mean arterial pressures were significantly different (P < 0.001). Side effects were common in both groups.

Conclusions

Buprenorphine added to bupivacaine provides earlier onset and longer postoperative epidural analgesia than epidural butorphanol with bupivacaine.

Lack of concentration-dependent local toxicity of highly concentrated (5%) versus conventional 0.5% bupivacaine following musculoskeletal surgery in a rat model

PURPOSE

Various sustained-release formulations incorporate high bupivacaine concentrations but data on local toxicity is lacking. This study explores local toxic effects of highly concentrated (5%) bupivacaine compared to clinically used concentrations in vivo following skeletal surgery, to assess the safety of sustained-release formulations with high bupivacaine concentrations.

METHODS

Sixteen rats underwent surgery, in which screws with catheters affixed were implanted in the spine or femur in a factorial experimental design, allowing single-shot or continuous 72 h local administration of 0.5%, 2.5% or 5.0% bupivacaine hydrochloride. During the 30-day follow-up, animal weight was recorded and blood samples were obtained. Implantation sites underwent histopathological scoring for muscle damage, inflammation, necrosis, periosteal reaction/thickening and osteoblast activity. Effects of bupivacaine concentration, administration mode and implantation site on local toxicity scores were analyzed.

RESULTS

Chi-squared tests for score frequencies revealed a concentration-dependent decrease in osteoblast count. Moreover, spinal screw implantation led to significantly more muscle fibrosis but less bone damage than femoral screw implantation, reflecting the more invasive muscle dissection and shorter drilling times related to the spinal procedure. No differences between bupivacaine administration modes regarding histological scoring or body weight changes were observed. Weight increased, while CK levels and leukocyte counts decreased significantly during follow-up, reflecting postoperative recovery. No significant differences in weight, leukocyte count and CK were found between interventional groups.

CONCLUSION

This pilot study found limited concentration-dependent local tissue effects of bupivacaine solutions concentrated up to 5.0% following musculoskeletal surgery in the rat study population.

Postoperative Analgesic Efficacy of Intraoperative Pectoral Nerve Block for Modified Radical Mastectomy: a Double-Blind Prospective Randomised Interventional Study

Severe acute postoperative pain following breast surgery increases the risk of persistent pain and affects the recovery of patients. Recently, pectoral nerve (PECs) block has gained significance as a regional fascial block that can provide adequate postoperative analgesia. This study aimed to evaluate the safety and efficacy of PECs II block, which was given intraoperative under direct vision after performing modified radical mastectomy for breast cancer patients. This prospective randomised study was comprised of a PECs II group (n = 30) and a control group (n = 30). Group A patients received 25 ml of 0.25% bupivacaine for PECs II block intraoperatively after the surgical resection was done. Both groups were compared with respect to the demographic and clinical parameters, total intraoperative fentanyl dose, total duration of surgery, postoperative pain score (Numerical Rating Scale) and the analgesic requirement, postoperative complications, postoperative duration of hospital stay, and the outcome. Intraoperative PECs II block was not associated with any increase in the duration of surgery. The postoperative pain scores were significantly higher in the control group till 24 h after the surgery, and so was the postoperative analgesic requirement. Patients in the PECs group were found to have rapid recovery and decreased postoperative complications. Intraoperative PECs II block is not only safe, time-saving procedure but also significantly reduces the postoperative pain and analgesic requirement in breast cancer surgeries. It is also associated with a faster recovery, decreased postoperative complications, and better patient satisfaction.

Manipulation and Processing of Spectral Signals for the Assay of the Newly Authorized Mixture of Bupivacaine/Meloxicam Using a Fully Green Solvents and A comparative Green Evaluation Supporting the Greenness and Sustainability of the Developed Smart Spectrophotometric Methods

BACKGROUND

Bupivacaine/Meloxicam combination is the first extended-release dual-acting local anesthetic (DALA) that provides 72 h. of postoperative pain relief. It reduces opioid use after surgery and manages pain better than bupivacaine alone over 72 h. it overcomes surgical site inflammation with a new synergistic mode of action that combines bupivacaine with a low dosage of meloxicam.

OBJECTIVE

In today's pharmaceutical research, we take great care to only use non-toxic solvents that pose no threat to either humans or the environment. This work determines bupivacaine (BVC) and meloxicam (MLX) simultaneously, utilizing water and 0.1 M HCl in water as solvents, respectively. Moreover, the eco-friendliness of the specified solvents and the whole system of equipment was evaluated based on how user-friendly they were using four standard methodologies.

METHODS

By relying on predefined software features with zero-order, derivative or ratio spectra, these techniques need the usage of elementary mathematical filters. The current techniques included, Dual wavelength (DW), fourier self-deconvolution (FSD), first derivative (D1), ratio difference (RD), and first ratio derivative (DD1) are the names of these methods.

RESULTS

Linearity was confirmed over a concentration range of 50-700 μg/mL for BVC and 1-10 μg/mL for MLX. For BVC and MLX, the limits of quantitation were between 26.85-41.33 μg/mL and 0.21-0.95 μg/mL, while the limits of detection were between 8.86-13.64 μg/mL and 0.06-0.31 μg/mL, respectively. For the full validation of the proposed methods ICH criteria were followed.

CONCLUSIONS

Current methods have the advantage of sticking to the basis of zero-order, derivative, or ratio spectra and needing just the barest minimum of data processing; no complex software, extended stages, or transformations are needed.

HIGHLIGHTS

No spectrophotometric methods have been published for the simultaneous analysis of BVC and MLX. As a result, the newly developed spectrophotometric approaches hold great relevance and originality in the field of pharmaceutical analysis.

Intradermal and Intramuscular Bupivacaine Reduces Opioid Use Following Noninstrumented Spine Surgery

OBJECTIVE

To evaluate the efficacy of intraoperative bupivacaine hydrochloride wound infiltration as an adjunct means of pain relief following noninstrumented posterior spine surgery.

METHODS

A retrospective cohort analysis was performed of all patients who underwent posterior spinal decompression surgery at the University of California, San Diego, and at the San Diego VA Medical Center between June 2020 and July 2021, following a change in practice to including bupivacaine infiltration at the end of the surgery. Patients were stratified into groups based on whether they received intrawound bupivacaine during surgery. Demographic and clinical data were extracted from the electronic health record. Postoperative opioid use, visual analog pain scores, heart rate, and blood pressure were compared.

RESULTS

The analysis included 43 patients; 21 received bupivacaine infiltration, and 22 did not. No complications were encountered in the perioperative period. Patients who received bupivacaine consumed significantly less opioids over the 72 hours following surgery, had slightly lower pain scores, and experienced slightly lower heart rates. No significant difference was found between groups with respect to systolic blood pressure, operative time, or length of hospital stay.

CONCLUSIONS

Intraoperative infiltration of the exposed paraspinous musculature and peri-incisional subdermal layer with bupivacaine significantly reduced postoperative opioid consumption for 72 hours after surgery and slightly reduced pain ratings and conferred superior heart rate control. This low-cost intervention produced significant patient benefit with minimal risk and no significant increase in surgical time or hospital stay.

A prospective, randomized, triple-blind comparative study of ropivacaine-dexmedetomidine versus ropivacaine alone in peribulbar blocks

Background and Aims

Bupivacaine and lidocaine mixtures are the commonly used local anesthetic drugs for the peribulbar blocks. Because of its safe anesthetic profile, ropivacaine is being investigated as an alternative agent. Several centers have evaluated the effect of the addition of an adjuvant like dexmedetomidine (DMT) to ropivacaine in enhancing the block characteristics. We proposed to evaluate the effect of the addition of DMT to ropivacaine versus a control group not having DMT as adjuvant.

Material and Methods

A prospective, randomized comparative study was conducted on a total of 80 patients attending our hospital for cataract surgeries. Patients were allocated into four groups of 20 each (n = 20) and peribulbar blocks were given 6 mL of 0.75% ropivacaine in group R and 6 mL of 0.75% ropivacaine plus 10 μg, 15 μg, and 20 μg DMT, respectively, in groups RD1, RD2, and RD3.

Results

When DMT was used as an adjunct to ropivacaine, there was a prolongation of the duration of the sensory block.

Conclusion

In peribulbar blocks, 6 mL of ropivacaine 0.75% produces satisfactory block characteristics, and the addition of 10 μg, 15 μg, or 20 μg of DMT as an adjuvant to ropivacaine 0.75% had the effect of significantly prolonging the duration of the sensory block, which is directly proportional to the dose of DMT employed. However, 20 μg of DMT added as an adjuvant to ropivacaine 0.75% appears to be the optimal dose, as this anesthetic drug mixture provides maximum prolongation of the sensory block besides providing satisfactory operating conditions, acceptable sedation levels, and stable hemodynamic parameters.

Increasing the Safety Profile of Follicular Unit Extraction by Eliminating the Use of Bupivacaine and Nerve Block: Experience from a Tertiary Care Center of North India

Introduction

Follicular unit extraction (FUE) is a safe and effective procedure in the hands of an expert. Side effects, particularly those which can lead to significant morbidity or mortality, are unacceptable as the procedure is done purely for cosmetic reasons. Any modification that decreases the risk associated with the procedure should be promoted.

Aim and Objective

The study was conducted to determine whether FUE can be carried out effectively with the elimination of nerve blocks and bupivacaine from the procedure.

Materials and Methods

The study was conducted in 30 patients suffering from androgenetic alopecia. The donor areas was anesthetized using lignocaine with adrenaline just below the area to be harvested. The anesthetic was injected intradermally resulting in the development of wheals in continuity, forming a linear line. From our previous experience, we found intradermal administration of lignocaine to give better anesthetic effect as compared to subcutaneous administration, although the former is more painful. This was followed by injection of tumescent into the donor area and donor harvesting, which lasted for a couple of hours. The recipient area was anesthetized using a similar technique of linear injection of anesthetic just ahead of the proposed hair line.

Results

The total amount of lignocaine with adrenaline consumed during the surgery ranged from a minimum of 6.1 ml to 8.5 ml, with an average of 7.6 ml. The average duration of the entire surgery was 6.5 h, ranging from 4.5 to 8.5 h. None of the patients experienced any pain during the entire surgery, and there were no significant side effects related to anesthetic administration in any patient.

Discussion

We found lignocaine with adrenaline to be a very safe and effective anesthetic agent for field block anesthesia in FUE. The exclusion of bupivacaine and nerve blocks from the procedure of FUE can further increase the safety of the procedure, particularly for beginners and in cases where the area to be covered is not extensive (Norwood-Hamilton grades 3, 4, and 5).

Spinal anesthesia in infants undergoing urologic surgery duration greater than 60 minutes

INTRODUCTION

Spinal anesthesia (SA) has been safely utilized in infants. There are limited data regarding the safety and efficacy of SA in pediatric urologic surgery lasting ≥60 min. We outlined the perioperative course for infants undergoing single-injection 0.5% plain bupivacaine SA-only for urologic procedures lasting ≥60 min.

OBJECTIVE

To characterize the safety and efficacy of SA for urologic surgery in infants lasting ≥60 min.

METHODS

We reviewed our prospectively maintained database of infants undergoing SA for urologic procedures lasting ≥60 min from May 2018 to March 2021. Patients received preoperative intranasal dexmedetomidine, some received intranasal fentanyl, and all patients received lidocaine cream applied preoperatively over the lumbar spine. Oral sucrose on a pacifier was provided as needed, and the patient's arms were swaddled for the procedure. Success was defined as no conversion to general anesthesia. Time points for start/end of spinal injection, procedure duration, wheels in/out of operating room (OR), and discharge were collected.

RESULTS

Of 245 cases conducted with SA during the study period, 76 (31%) infants underwent surgery lasting ≥60 min. Of these, 73 (96%) were successfully completed with SA alone. In the 3 cases converted to general anesthesia, 2 (67%) required mask anesthesia after 96 and 169 min (for the last <10 min of surgery), and one was converted to intubation before start of surgery. Median patient age was 6 (IQR 5-7) months, and median procedure length was 95 (IQR 75-120) minutes. Following initial preoperative intranasal dexmedetomidine ± fentanyl, at least one additional dose of IV sedative was given in 27 (36%) cases at a median time of 90 (IQR 60-120) minutes into surgery. Following closure, patients exited the OR after a median 10 (IQR 8-12) minutes and subsequently discharged after spending a median of 73 (IQR 61-96) minutes in recovery.

DISCUSSION

We describe pediatric urologic surgical cases lasting ≥60 min that employed single-injection intrathecal bupivacaine alone without adjunct intrathecal agents. In this report, SA was safely utilized in infants undergoing urologic procedures lasting at least 60 min, with about 40% of patients receiving additional IV dexmedetomidine and fentanyl. Non-medication measures (swaddling, oral sucrose) were important for maximizing patient comfort. Communication between surgeon and anesthesia as cases progress is key to maintaining adequate anesthesia.

CONCLUSION

A single-injection bupivacaine-only spinal anesthesia approach for urologic surgery lasting over an hour and up to 3 h is safe and effective in infants. Selecting appropriate candidates for SA should be a joint decision between the surgeon and the anesthesiologist.

Role of Pre-incisional Bupivacaine Infiltration in Post-tonsillectomy Analgesia

Tonsillectomy is one of the common surgeries performed by Otorhinolaryngologists and is associated with several morbidities with pain being the commonest, which can cause considerable delay in oral intake and discharge from the hospital. As a commonly performed day care procedure nowadays, pain control is much better than what it used to be previously observed. Therefore newer drugs are being constantly studied inorder to give better analgesia and post operative comfort to the patient with minimal side effects. The main obstacle being finding the best medical method to control pain with minimum side effects, but at the same time making sure that the patient is adequately hydrated and they resume regular eating as soon as possible. Our aim is to study the role of pre-incisional 0.5% bupivacaine versus normal saline infiltration in post-tonsillectomy analgesia. Over a period of 1 year, 30 patients with each group of 15 were compared for the efficacy of 0.5% bupivacaine and 0.9% normal saline in post-operative tonsillectomy pain management. After thorough clinical examination and investigations, all patients underwent tonsillectomy by dissection and snare method. After intubation, 0.5% bupivacaine or normal saline was infiltrated in the tonsillar fossa and pain scores was obtained using Visual Analogue Scale (V.A.S) at 6, 12 and 24 h post operatively. Using Mann-Whitney non-parametric statistical test, inter-group analysis was done which showed highly significant p-value (<0.0001) indicating that the pre-incisional bupivacaine infiltration is highly effective in reducing the post-tonsillectomy pain. Hence, we recommend the routine use of pre-incisional peritonsillar infiltration of 0.5% bupivacaine in all tonsillectomy/adenotonsillectomy cases, irrespective of the age of the patient to reduce the post tonsillectomy pain and other discomfort associated with it.

Development and in vivo validation of phospholipid-based depots for the sustained release of bupivacaine

By direct deposition of the drug at the local site of action, injectable depot formulations - intended for treatment of a local disease or for local intervention - are designed to limit the immediate exposure of the active principle at a systemic level and to reduce the frequency of administration. To overcome known drawbacks in the production of some marketed phospholipid-based depots, here we propose to manufacture drug-loaded negatively charged liposomes through conventional technologies and to control their aggregation mixing a solution of divalent cations prior to administration. We identified phosphatidylglycerol (PG) as the most suitable phospholipid for controlled aggregation of the liposomes and to modulate the release of the anesthetic bupivacaine (BUP) from liposomal depots. In vivo imaging of the fluorescently-labelled liposomes showed a significantly higher retention of the PG liposomes at the injection site with respect to zwitterionic ones. In situ mixing of PG liposomes with calcium salts significantly extended the area under the curve of BUP in plasma compared to the non-depot system. Overall, controlling the aggregation of negatively charged liposomes with divalent cations not only modulated the particle clearance from the injection site but also the release in vivo of a small amphipathic drug such as BUP.

Comparative study to assess the effect of ropivacaine and a mixture of lidocaine and bupivacaine on intraocular pressure after peribulbar anesthesia for cataract surgery

Purpose

To compare the efficacy of ropivacaine with a mixture of lidocaine and bupivacaine in peribulbar anesthesia for cataract surgery, in terms of post-block intraocular pressure (IOP).

Methods

A one-year comparative study was done to compare two anesthetic solutions in peribulbar anesthesia for cataract surgery, from January 2020 to December 2020 at a tertiary health care hospital. Two hundred patients (40-70 years of age) planned for small-incision cataract surgery with posterior chamber intraocular lens (IOL) implantation under peribulbar anesthesia were included in the study. A single-site inferotemporal injection was given till a total eyelid drop was observed. The IOP was measured at four time-points: before block (control), 1-, 5-, and 15-minute post-block with a tonometer.

Results

The 1-minute post-block mean IOP in both the groups was higher than the baseline levels. This reflected raised intraorbital pressure secondary to peribulbar injection of local anesthetic. However, the rise in 1-minute post-block IOP was significantly less in the ropivacaine group. The 5- and 15-min post-block mean IOP values in the ropivacaine group were significantly lower than the corresponding values of the lidocaine-bupivacaine group and baseline (control) ropivacaine values.

Conclusion

The results of this study support that ropivacaine as a local anesthetic drug for peribulbar block for small-incision cataract surgery can be a suitable alternative to the lidocaine-bupivacaine combination. Studies involving a larger sample size are required to consider ropivacaine as a superior drug to the lidocaine-bupivacaine combination.

Systematic literature review of topical local anaesthesia or analgesia to donor site wounds

BACKGROUND

Topical local analgesic and anaesthetic agents have been used both pre- and immediately post-harvest on split-thickness skin graft (STSG) donor site wounds (DSW). There is no systematic review of their effectiveness in providing post-harvest analgesia, or of the possible toxic effects of systemic absorption. This study is designed to address the question of which agent, if any, is favoured over the others and whether there are any safety data regarding their use.

METHODS

Systematic literature review of randomised controlled trials of topical agents applied to STSG DSWs, with a view to providing analgesia. Studies identified via search of Cochrane and EBSCO databases. No restrictions on language or publication year. Primary outcomes: pain at the time of (awake) STSG, and post-harvest pain (up to first dressing change). Secondary outcome was serum medication levels relative to published data on toxic doses. Cochrane risk of bias assessment tool utilised in assessment of included studies. At least 2 reviewers screened and reviewed included studies. A narrative review is presented.

RESULTS

There were 11 studies meeting inclusion criteria. Overall methodological quality and patient numbers were low. Topical eutectic mixture of lidocaine and prilocaine pre-harvest affords good local anaesthesia in awake STSG harvesting. Topical bupivacaine (5 studies) or lidocaine (1 study) gave significantly better post-harvest anaesthesia/analgesia than placebo. Topical morphine performs no better than placebo. Topical local anaesthetic agents at reported doses were all well below toxic serum levels.

CONCLUSIONS

Topical local anaesthetics (lidocaine or bupivacaine) provide good analgesia, both during and after STSG harvest, at well below toxic serum levels, but there are no good data determining the best local anaesthetic agent to use. There is no evidence morphine performs better than placebo.