Local anesthetic dosing and toxicity of adult truncal catheters: a narrative review of published practice.

BACKGROUND/IMPORTANCE: Anesthesiologists frequently use truncal catheters for postoperative pain control but with limited characterization of dosing and toxicity. OBJECTIVE: We reviewed the published literature to characterize local anesthetic dosing and toxicity of paravertebral and transversus abdominis plane catheters in adults. EVIDENCE REVIEW: We searched the literature for bupivacaine or ropivacaine infusions in the paravertebral or transversus abdominis space in humans dosed for 24 hours. We evaluated bolus dosing, infusion dosing and cumulative 24-hour dosing in adults. We also identified cases of local anesthetic systemic toxicity and toxic blood levels. FINDINGS: Following screening, we extracted data from 121 and 108 papers for ropivacaine and bupivacaine respectively with a total of 6802 patients. For ropivacaine and bupivacaine, respectively, bolus dose was 1.4 mg/kg (95% CI 0.4 to 3.0, n=2978) and 1.0 mg/kg (95% CI 0.18 to 2.1, n=2724); infusion dose was 0.26 mg/kg/hour (95% CI 0.06 to 0.63, n=3579) and 0.2 mg/kg/hour (95% CI 0.06 to 0.5, n=3199); 24-hour dose was 7.75 mg/kg (95% CI 2.1 to 15.7, n=3579) and 6.0 mg/kg (95% CI 2.1 to 13.6, n=3223). Twenty-four hour doses exceeded the package insert recommended upper limit in 28% (range: 17%-40% based on maximum and minimum patient weights) of ropivacaine infusions and 51% (range: 45%-71%) of bupivacaine infusions. Toxicity occurred in 30 patients and was associated with high 24-hour dose, bilateral catheters, cardiac surgery, cytochrome P-450 inhibitors and hypoalbuminemia. CONCLUSION: Practitioners frequently administer ropivacaine and bupivacaine above the package insert limits, at doses associated with toxicity. Patient safety would benefit from more specific recommendations to limit excessive dose and risk of toxicity.

Ropivacaine-loaded hydrogels for prolonged relief of chemotherapy-induced peripheral neuropathic pain and potentiated chemotherapy.

Chemotherapy can cause severe pain for patients, but there are currently no satisfactory methods of pain relief. Enhancing the efficacy of chemotherapy to reduce the side effects of high-dose chemotherapeutic drugs remains a major challenge. Moreover, the treatment of chemotherapy-induced peripheral neuropathic pain (CIPNP) is separate from chemotherapy in the clinical setting, causing inconvenience to cancer patients. In view of the many obstacles mentioned above, we developed a strategy to incorporate local anesthetic (LA) into a cisplatin-loaded PF127 hydrogel for painless potentiated chemotherapy. We found that multiple administrations of cisplatin-loaded PF127 hydrogels (PFC) evoked severe CIPNP, which correlated with increased pERK-positive neurons in the dorsal root ganglion (DRG). However, incorporating ropivacaine into the PFC relieved PFC-induced CIPNP for more than ten hours and decreased the number of pERK-positive neurons in the DRG. Moreover, incorporating ropivacaine into the PFC for chemotherapy is found to upregulate major histocompatibility complex class I (MHC-I) expression in tumor cells and promote the infiltration of cytotoxic T lymphocytes (CD8+ T cells) in tumors, thereby potentiating chemotherapy efficacy. This study proposes that LA can be used as an immunemodulator to enhance the effectiveness of chemotherapy, providing new ideas for painless cancer treatment.

A randomized trial: The safety, pharmacokinetics and preliminary pharmacodynamics of ropivacaine oil delivery depot in healthy subjects.

INTRODUCTION: Ropivacaine oil delivery depot (RODD) can slowly release ropivacaine and block nerves for a long timejavascript:;. The aim of the present work was to investigate the safety, pharmacokinetics, and preliminary pharmacodynamics of RODD in subcutaneous injection among healthy subjects. METHODS: The abdomens of 3 subjects were subcutaneously administered with a single-needle RODD containing 12~30 mg of ropivacaine. The irritation, nerve blocking range and optimum dose were investigated. Forty-one subjects were divided into RODD groups containing 150, 230, 300, 350 and 400 mg of ropivacaine and a ropivacaine hydrochloride injection (RHI) 150 mg group. Multineedle subcutaneous injection of RODD or RHI was performed in the abdomens of the subjects. The primary endpoint was a safe dose or a maximum dose of ropivacaine (400 mg). Subjects' vital signs were observed; their blood was analyzed; their cardiovascular system and nervous systems were monitored, and their dermatological reactions were observed and scored. Second, the ropivacaine concentrations in plasma were determined, pharmacokinetic parameters were calculated, and the anesthetic effects of RODD were studied, including RODD onset time, duration and intensity of nerve block. RESULTS: Single-needle injection of RODD 24 mg was optimal for 3 subjects, and the range of nerve block was 42.5±20.8 mm. Multineedle subcutaneous injection of RODD in the abdomens of subjects was safe, and all adverse events were no more severe than grade II. The incidence rate of grade II adverse events, such as pain, and abnormal ST and ST-T segment changes on electrocardiography, was approximately 1%. The incidence rate of grade I adverse events, including erythema, papules, hypertriglyceridemia, and hypotension was greater than 10%. Erythema and papules were relieved after 24 h and disappeared after 72 h. Other adverse reactions disappeared after 7 days. The curve of ropivacaine concentration-time in plasma presented a bimodal profile. The results showed that ropivacaine was slowly released from the RODD. Compared with the 150 mg RHI group, Tmax was longer in the RODD groups. In particular, Tmax in the 400 mg RODD group was longer than that in the RHI group (11.8±4.6 h vs. 0.77±0.06 h). The Cmax in the 150 mg RODD group was lower than that in the 150 mg RHI group (0.35±0.09 vs. 0.58±0.13 µg·mL-1). In particular, the Cmax increased by 48% when the dose was increased by 2.6 times in the 400 mg group. Cmax, the AUC value and the intensity of the nerve block increased with increasing doses of RODD. Among them, the 400 mg RODD group presented the strongest nerve block (the percentage of level 2 and 3, 42.9%). The corresponding median onset time was 0.42 h, and the duration median was 35.7⁓47.7 h. CONCLUSIONS: RODD has a sustained release effect. Compared with the RHI group, Tmax was delayed in the RODD groups, and the duration of nerve block was long. No abnormal reaction was found in the RODD group containing 400 mg of ropivacaine after subcutaneous injection among healthy subjects, suggesting that RODD was adequately safe. TRIAL REGISTRATION: Chictr.org: CTR2200058122; Chinadrugtrials.org: CTR20192280.

Dexmedetomidine protects against Ropivacaine-induced neuronal pyroptosis via the Nrf2/HO-1 pathway.

Dexmedetomidine (DEX) has been demonstrated to protect against ropivacaine (Ropi)-induced neuronal damages. This study was conducted to explore the protective role of DEX in Ropi-induced neuronal pyroptosis and provide a strategy to eliminate Ropi-induced neurotoxicity. The impacts of different concentrations of Ropi and DEX on neurotoxicity in SK-N-SH cells were evaluated by cell counting kit-8 assay and lactic dehydrogenase assay kits. Levels of nuclear factor erythroid 2-related factor 2 (Nrf2), heme oxygenase 1 (HO-1), NLR family pyrin domain containing 3 (NLRP3), cleaved Caspase-1, cleaved N-terminal gasdermin D, interleukin (IL)-1ß, and IL-18 were measured by real-time quantitative PCR, Western blotting, and enzyme linked immunosorbent assay. The Nrf2 level after nuclear/cytoplasmic separation was quantified. SK-N-SH cells were treated with si-Nrf2, Nigericin (NLRP3 activator), and Zinc Protoporphyrin (HO-1 inhibitor) to validate the mechanism. Ropi reduced SK-N-SH cell viability in a concentration- and time-dependent manner. DEX treatment alleviated Ropi-induced toxicity and inhibited pyroptosis. Ropi increased the expression levels of Nrf2 and HO-1, and DEX further enhanced the increases and promoted Nrf2 nuclear translocation. Nrf2/HO-1 inhibition or NLRP3 activation both neutralized the inhibitory role of DEX in Ropi-induced pyroptosis of SK-N-SH cells. Overall, DEX promoted the Nrf2/HO-1 pathway to inhibit NLRP3 expression, thus alleviating Ropi-induced neuronal pyroptosis.

Cardiac Arrest after Small Doses Ropivacaine: Local Anesthetic Systemic Toxicity in the Course of Continuous Femoral Nerve Blockade.

BACKGROUND: The paper presents a case report of an episode of local anesthetic systemic toxicity (LAST) with cardiac arrest after continuous femoral nerve blockade. CASE REPORT: A 74-year-old patient burdened with hypertension and osteoarthritis underwent elective total knee replacement surgery. After surgery, a continuous femoral nerve blockade was performed and an infusion of a local anesthetic (LA) was started using an elastomeric pump. Five hours after surgery, the patient had an episode of generalized seizures followed by cardiac arrest. After resuscitation, spontaneous circulation was restored. In the treatment, 20% lipid emulsion was used. On day two of the ICU stay, the patient was fully cardiovascularly and respiratorily stable without neurological deficits and was discharged to the orthopedic department to continue treatment. CONCLUSION: Systemic toxicity of LA is a serious and potentially fatal complication of the use of LA in clinical practice. It should be noted that in nearly 40% of patients, LAST deviates from the classic and typical course and may have an atypical manifestation, and the first symptoms may appear with a long delay, especially when continuous blockades are used. Therefore, the proper supervision of the patient and the developed procedure in the event of LAST is undoubtedly important here.

Continuous Transversus Abdominis Plane Infusion via Surgically Inserted Catheter for Postoperative Analgesia After Abdominal Aortic Surgery by Retroperitoneal Approach: TAPCACAO Study.

BACKGROUND: The purpose of our study was to evaluate the analgesic properties of continuous transversus abdominis plane (TAP) infusion with ropivacaine compared to placebo for postoperative analgesia in elective surgery of the abdominal aorta by retroperitoneal exposure. METHODS: We conducted a prospective, single-center, randomized, double-blind study comparing a group of patients with a TAP catheter undoing ropivacaine infusion with a placebo group. Patients received a left retroperitoneal pararectal exposure for abdominal aortic surgery. A continuous infusion catheter was placed under visual control by the surgeon before closure and removed after 48 hr. All patients had postoperative patient-controlled analgesia with morphine. The primary endpoint was morphine consumption during the first 24 hr. RESULTS: The analysis included 25 patients in the placebo group and 24 in the ropivacaine group. The average morphine consumption during the first 24 hr was significantly different, with 31 ± 16 mg in the ropivacaine group and 41 ± 17 mg in the placebo group (P = 0.019). At 48 hr, morphine consumption was still lower in the ropivacaine group (42 ± 26 mg) than in the placebo group (64 ± 25 mg) (P = 0.003). The opioid narcotic-related side effects of opioid infusion (postoperative nausea and vomiting, constipation) and length of hospital stay were similar in both populations. CONCLUSIONS: Our study showed that continuous TAP block with ropivacaine via surgically inserted catheter significantly decreased morphine consumption at 24 and 48 hr after elective abdominal aortic surgery by retroperitoneal exposure.

Subfascial infiltration of 0.5% ropivacaine, but not 0.25% ropivacaine, exacerbates damage and inflammation in surgically incised abdominal muscles of rats.

Ropivacaine-induced myotoxicity in surgically incised muscles has not been fully investigated. We evaluated the effects of infiltration anesthesia with ropivacaine on damage, inflammation and regeneration in the incised muscles of rats undergoing laparotomy. Ropivacaine or saline was infiltrated below the muscle fascia over the incised muscles. Pain-related behaviors and histological muscle damage were assessed. Macrophage infiltration at days 2 and 5 and proliferation of satellite cells at day 5 were detected by CD68 and MyoD immunostaining, respectively. Pain-related behaviors were inhibited by 0.25% and 0.5% of ropivacaine for 2 h after surgery. Single infiltration of 0.5% ropivacaine did not induce injury in intact muscles without incision, but single and repeated infiltration of 0.5% ropivacaine significantly augmented laparotomy-induced muscle injury and increased the numbers of CD68-positve macrophages and MyoD-positive cells compared to those in rats with infiltration of saline or 0.25% ropivacaine. In contrast, there were no significant differences in them between rats with saline infusion and rats with 0.25% ropivacaine infiltration. In conclusion, single or repeated subfascial infiltration of 0.25% ropivacaine can be used without exacerbating the damage and inflammation in surgically incised muscles, but the use of 0.5% ropivacaine may be a concern because of potentially increased muscle damage.

Postoperative Analgesic Efficacy and Safety of Ropivacaine Plus Diprospan for Preemptive Scalp Infiltration in Patients Undergoing Craniotomy: A Prospective Randomized Controlled Trial.

BACKGROUND: Preemptive injection of local anesthetics can prevent postoperative pain at the incision site, but the analgesic effect is insufficient and is maintained only for a relatively short period of time. Diprospan is a combination of quick-acting betamethasone sodium phosphate and long-acting betamethasone dipropionate. Whether Diprospan as an adjuvant to local anesthetic can achieve postcraniotomy pain relief has not been studied yet. METHODS: This is a prospective, single-center, blinded, randomized, controlled clinical study, which included patients ages 18 and 64 years, with American Society of Anaesthesiologists (ASA) physical statuses of I to III, scheduled for elective supratentorial craniotomy. We screened patients for enrollment from September 3, 2019, to August 15, 2020. The final follow-up was completed on February 15, 2021. Eligible patients were randomly assigned to either the Diprospan group, who received incision-site infiltration of 0.5% ropivacaine plus Diprospan (n = 48), or the control group, who received 0.5% ropivacaine alone (n = 48), with a distribution ratio of 1:1. Primary outcome was the cumulative sufentanil (µg) consumption through patient-controlled analgesia (PCA) within 48 hours after surgery. Primary analysis was performed based on the intention-to-treat (ITT) principle. RESULTS: Baseline characteristics were not significantly different between the 2 groups ( P > .05). In the Diprospan group, the cumulative sufentanil consumption through PCA was 5 (0-16) µg within 48 hours postoperatively, which was significantly lower than that in the control group (38 [30.5-46] µg; P < .001). CONCLUSIONS: Infiltration of ropivacaine and Diprospan can achieve satisfactory postoperative pain relief after craniotomy; it is a simple, easy, and safe technique, worth clinical promotion.

Ropivacaine induced systemic toxicity in a patient with phacomatosis pigmentokeratotica.

Calculation of the maximum recommended dose of local anesthetic minimizes the risk of Local Anesthetic Systemic Toxicity (LAST) when administrating multiple blocks for lower limb surgeries. Ropivacaine is the preferred local anesthetic as it is less lipophilic than bupivacaine and thus results in less central nervous system (CNS) and cardiovascular toxicity. The presence of developmental, congenital, and metabolic disorders mandates an extracautious approach in the administration of large volume of Local anaesthesia (LA) as the vascularity of the limb, levels of alpha-1-acid glycoprotein, and sensitivity of the sodium channels may be altered. This case report highlights successful resuscitation of a patient with Phacomatosis pigmentokeratotica after the development of CNS toxicity secondary to the administration of ropivacaine in ultrasound-guided combined lumbar plexus and sciatic nerve block. We identified some high risk patient profiles which should be vigilantly monitored to minimize the incidence of LAST.

P53 inhibitor pifithrin-α inhibits ropivacaine-induced neuronal apoptosis via the mitochondrial apoptosis pathway.

The neurotoxicity of local anesthetics (LAs) has attracted more and more attention, However, they lack preventive and therapeutic measures. Many studies have shown that apoptosis plays an important role in the process of LA-induced neurotoxicity. As an important signaling molecule to activate apoptosis, p53 has been proved to be involved in the neurotoxicity induced by LAs, but the mechanism is unclear. In this study, we explored the effect of pifithrin-α (PFT-α), a p53 inhibitor, on apoptosis by ropivacaine (Rop) in vivo and in vitro. Cell viability and apoptosis detected by CCK-8 and a JC-1 apoptosis detection kit, the changes of spinal cord structure observed after hematoxylin and eosin staining, apoptosis of the spinal cord measured by terminal deoxynucleotidyl transferase dUTP nick end labeling staining, behavioral assessment of the nerve Injury evaluated by the detection of sciatic nerve conduction velocity (SNCV) andmechanical withdrawal threshold (MWT), the expression of p53 and many apoptosis-related genes included Bax, Bcl-2, and caspase-3 detected by quantitative real-time polymerase chain reaction, Western blot analysis, immunofluorescence, and immunohistochemistry. Results showed that PC12 cell viability decreased because of Rop, but the pretreatment of PFT-α could protect it. And PFT-α reduced the injuries in the spinal cord by Rop included vacuoles or edema. The results of immunofluorescence and immunohistochemistry testing showed that PFT-α inhibited the p53 protein upregulated by Rop. Apoptosis rate and many proapoptotic genes include p53, Bax, caspase-3 messenger RNA, and proteins were increased by Rop, but PFT-α could decrease it. In conclusion, PFT-α inhibited cell apoptosis and spinal cord injuries induced by Rop.

The effect of perineural dexamethasone on rebound pain after ropivacaine single-injection nerve block: a randomized controlled trial.

BACKGROUND: Rebound pain after a single-shot nerve block challenges the real benefit of this technique. We aimed to investigate whether perineural dexamethasone addition decreased the incidence of rebound pain after a single-shot nerve block. METHODS: We randomly allocated 132 patients scheduled for open reduction internal fixation of an upper extremity closed fracture under single-shot peripheral nerve block and sedation into two groups. Patients in the dexamethasone group received nerve block with 0.375% ropivacaine and 8 mg dexamethasone, while those in the control group received ropivacaine only. Sixty-three patients in the dexamethasone group and 60 patients in the control group were analyzed for the incidence of rebound pain 48 h after block administration, which was the primary outcome. The secondary outcomes included the highest self-reported numeric rating scale (NRS) pain score, and NRS at 8, 12, 24, and 48 h after the block, sufentanil consumption, sleep quality on the night of surgery, patient satisfaction with the pain therapy, blood glucose at 6 h after the block, pain and paresthesia at 30 days after surgery. RESULTS: The incidence of rebound pain was significantly lower in the dexamethasone group (7 [11.1%] of 63 patients) than in the control group (28 [48.8%] of 60 patients [RR = 0.238, 95% CI (0.113-0.504), p = 0.001]. Dexamethasone decreased opioid consumption in 24 h after surgery (p < 0.001) and improved the sleep quality score on the night of surgery (p = 0.01) and satisfaction with pain therapy (p = 0.001). Multivariate logistic regression analysis showed that only group allocation was associated with the occurrence of rebound pain [OR = 0.062, 95% CI (0.015-0.256)]. Patients in the dexamethasone group reported later onset pain (19.7 ± 6.6 h vs 14.7 ± 4.8 h since block administration, mean ± SD, p < 0.001) and lower peak NRS scores [5 (3, 6) vs 8 (5, 9), median (IQR), p < 0.001] than those in the control group. CONCLUSIONS: The perineural administration of 8 mg dexamethasone reduces rebound pain after a single-shot nerve block in patients receiving ORIF for an upper limb fracture. TRIAL REGISTRATION: This study was retrospectively registered in the Chinese Clinical Trial Registry ( ChiCTR-IPR-17011365 ) on May 11th, 2017.

Comparison of the Analgesic Duration of 0.5% Bupivacaine With 1:200,000 Epinephrine Versus 0.5% Ropivacaine Versus 1% Ropivacaine for Low-Volume Ultrasound-Guided Interscalene Brachial Plexus Block: A Randomized Controlled Trial.

BACKGROUND: Bupivacaine and ropivacaine are the preferred long-acting local anesthetics for peripheral nerve blocks as they provide prolonged analgesia in the postoperative period. No studies have directly compared the analgesic duration of these commonly used local anesthetics in the setting of low-volume ultrasound-guided interscalene block (US-ISB). This study was designed to determine which local anesthetic and concentration provides superior analgesia (duration and quality) for low-volume US-ISB. METHODS: Sixty eligible patients scheduled for arthroscopic shoulder surgery were randomized (1:1:1) to receive US-ISB (5 mL) with 0.5% bupivacaine with 1:200,000 epinephrine, 0.5% ropivacaine, or 1% ropivacaine. All individuals were blinded including study participants, anesthesiologists, surgeons, research personnel, and statistician. All participants received a standardized general anesthetic and multimodal analgesia. The primary outcome was duration of analgesia defined as the time from the end of injection to the time that the patients reported a significant increase in pain (>3 numeric rating scale [NRS]) at the surgical site. RESULTS: The mean duration of analgesia for 0.5% bupivacaine with 1:200,000 epinephrine, 0.5% ropivacaine, or 1% ropivacaine was 14.1 ± 7.4, 13.8 ± 4.5, and 15.8 ± 6.3 hours, respectively (analysis of variance [ANOVA], P = .51). There were no observed differences in analgesic duration or other secondary outcomes between the 3 groups with the exception of a difference in cumulative opioid consumption up to 20h00 on the day of surgery in favor of ropivacaine 0.5% over bupivacaine of minimal clinical significance. CONCLUSIONS: In the context of single-injection low-volume US-ISB, we have demonstrated a similar efficacy between equal concentrations of ropivacaine and bupivacaine. In addition, increasing the concentration of ropivacaine from 0.5% to 1% did not prolong the duration of US-ISB.

Epidural Administration of Ropivacaine Reduces the Amplitude of Transcranial Electrical Motor-Evoked Potentials: A Double-Blinded, Randomized, Controlled Trial.

BACKGROUND: An epidurally administered local anesthetic acts primarily on the epidural nerve roots and can act directly on the spinal cord through the dural sleeve. We hypothesized that epidurally administered ropivacaine would reduce the amplitude of transcranial electrical motor-evoked potentials by blocking nerve conduction in the spinal cord. Therefore, we conducted a double-blind, randomized, controlled trial. METHODS: Thirty adult patients who underwent lung surgery were randomly allocated to 1 of 3 groups, based on the ropivacaine concentration: the 0.2% group, the 0.375% group, and the 0.75% group. The attending anesthesiologists, neurophysiologists, and patients were blinded to the allocation. The epidural catheter was inserted at the T5-6 or T6-7 interspace by a paramedian approach, using the loss of resistance technique with normal saline. General anesthesia was induced and maintained using propofol and remifentanil. Transcranial electrical motor-evoked potentials were elicited by a train of 5 pulses with an interstimulus interval of 2 milliseconds by using a constant-voltage stimulator and were recorded from the tibialis anterior muscle. Somatosensory-evoked potentials (SSEPs) were evoked by electrical tibial nerve stimulation at the popliteal fossa. After measuring the baseline values of these evoked potentials, 10 mL of epidural ropivacaine was administered at the 0.2%, 0.375%, or 0.75% concentration. The baseline amplitudes and latencies recorded before administering ropivacaine were defined as 100%. Our primary end point was the relative amplitude of the motor-evoked potentials at 60 minutes after the epidural administration of ropivacaine. We analyzed the amplitudes and latencies of these evoked potentials by using the Kruskal-Wallis test and used the Dunn multiple comparison test as the post hoc test for statistical analysis. RESULTS: The data are expressed as the median (interquartile range). Sixty minutes after epidurally administering ropivacaine, the motor-evoked potential amplitude was lower in the 0.75% group (7% [3%-18%], between-group difference P < .001) and in the 0.375% group (52% [43%-59%]) compared to that in the 0.2% group (96% [89%-105%]). The latency of SSEP was longer in the 0.75% group compared to that in the 0.2% group, but the amplitude was unaffected. CONCLUSIONS: Epidurally administered high-dose ropivacaine lowered the amplitude of motor-evoked potentials and prolonged the onset latencies of motor-evoked potentials and SSEPs compared to those in the low-dose group. High-dose ropivacaine can act on the motor pathway through the dura mater.

Evaluation of Pectoral Nerve Block in Modified Radical Mastectomy: Comparison of Three Concentrations of Ropivacaine.

BACKGROUND: Pectoral nerve block type I (PECS I Block) and type II (PECS II Block) with ropivacaine are relatively new analgesic methods for breast-cancer surgery. We evaluated the safety and efficacy of different concentrations of ropivacaine given in the same volume for the PECS II Block in patients undergoing modified radical mastectomy (MRM). PATIENTS AND METHODS: One hundred and twenty women undergoing elective MRM who met inclusion criteria were divided randomly into four groups of 30: control group without PECS II Block and R0.2%, R0.3%, and R0.4% groups, who received general anesthesia plus the PECS II Block with ropivacaine at 0.2%, 0.3%, and 0.4%, respectively, in a volume of 40 mL. RESULTS: The postoperative numerical rating scale (NRS) pain score at rest and active was significantly higher in the control group than that in the three ropivacaine groups (P<0.05 for all), and the postoperative NRS score in the R0.3% group and R0.4% group at 12, 24, and 48 h postoperatively were significantly lower than that in the R0.2% group (P<0.05 for all); there was no significant difference between the R0.3% group and R0.4% group. The time when pain was first felt after MRM, the total number of complaints during 3, 6, 12, 24, and 48 h after MRM, and the total analgesic requirement (tramadol consumption) during the first 24 h postoperatively in the R0.3% group and R0.4% group were significantly lower than those in the control group and R0.2% group (P<0.05 for all); there was no significant difference between the R0.3% group and R0.4% group. CONCLUSION: A dose of 0.3% ropivacaine was the optimal concentration for a PECS II Block for patients undergoing MRM because it provided efficacious analgesia during and >48 h after MRM. Increasing the ropivacaine concentration did not improve the analgesia of the PECS II Block significantly.

Effects of dezocine and ropivacaine infiltration anesthesia on cellular immune function indicators, anesthesia recovery time and pain factors in patients with open liver resection.

The current experiment was carried out to explore the effects of dezocine combined with ropivacaine infiltration anesthesia on the anesthesia recovery time and pain factors of patients with open hepatectomy. A prospective randomized controlled method was used to select 92 patients with open liver cancer resection in our hospital from August 2017 to November 2019. The patients were divided into a study group (n=46) and a control group (n=46) using a computer-generated random number table. Both groups underwent general anesthesia, based on this, the study group was treated with ropivacaine infiltration anesthesia 10 minutes before skin incision, and dezocine was given intravenously 0.5 h before surgery, the control group was anesthetized with ropivacaine 10 minutes before the incision, and was given a saline injection 0.5 h before the operation. Compared the recovery of anesthesia (recovery time of spontaneous breathing, time to open eyes, time to extubation), the incidence of adverse reactions, and cellular immune function indicators (peripheral blood CD4+, CD4+/CD8+, NK cell levels), stress response indicators [serum blood glucose (Glu), norepinephrine (NE), adrenaline (E)], pain factors [serum dopamine (DA), neuropeptide Y (NPY), substance P (SP)] before induction of anesthesia (T0), completion of surgery (T1), 12 hours after surgery (T2), and 24 hours after surgery (T3) between the two groups, and the degree of pain (VAS score) at T2 and T3 were compared between the two groups. The levels of CD4+, CD4+/CD8+, and NK cells in peripheral blood at T1, T2, and T3 in the study group were higher than those in the control group (P<0.05); serum Glu, NE, and E levels in the study group at T1, T2, and T3 were lower than those in the control group (P<0.05); serum DA, NPY, and SP levels in the study group at T1, T2, and T3 were lower than those in the control group (P<0.05); the VAS scores of the study group at T2 and T3 were lower than those of the control group (P<0.05); the time of spontaneous breathing recovery, eyes opening and extubation in the study group were shorter than those in the control group (P<0.05); the incidence of restlessness (4.35%), transient hypertension (6.52%), and cough (2.17%) in the study group were lower than those in the control group (P<0.05). Dezocine and ropivacaine infiltration anesthesia can significantly shorten the recovery time of anesthesia and inhibit pain factor secretion in patients with open hepatectomy and can reduce the body's stress response after surgery, reduce immune function fluctuations, and can reduce the incidence of adverse reactions to anesthesia, and help promote patients' postoperative recovery.

Evaluation of Serratus Anterior Plane Block for Pain Relief in Patients Undergoing MIDCAB Surgery.

OBJECTIVE: The minimally invasive direct coronary artery bypass (MIDCAB) surgery is associated with severe chest pain in the first 2 to 3 postoperative days; this may delay the patient recovery. In this randomized controlled trial we evaluated the role of serratus anterior plane (SAP) block for postoperative pain relief in patients undergoing MIDCAB surgery. METHODS: Patients undergoing MIDCAB surgery were randomized into 2 groups of 25 each; SAP group received 20 mL of 0.2% ropivacaine with 1 µg/mL fentanyl as bolus followed by infusion at 8 mL/h; control group received saline for both bolus and infusion. Primary outcome measure was postoperative pain when supine, and during deep inspiration, coughing, and patient movement; secondary outcome measures were requirement of postoperative intravenous fentanyl and opioid-related side effects. All patients were followed at 6-hourly intervals for 48 hours in the postoperative period. Results were analyzed by the Student's t -test, χ 2 test, Mann-Whitney U-test and Kruskall-Wallis test. A P-value <0.05 was considered significant. RESULTS: The 2 groups were similar with respect to patient characteristics. Static and dynamic pain visual analog scale scores were significantly reduced in the SAP group as compared to the control group at most of the time points of assessment (P < 0.05). Patient-controlled fentanyl requirements were reduced in the SAP group as compared to control group on the second postoperative day (P < 0.05). CONCLUSIONS: SAP block reduced the postoperative pain scores and opioid requirements in patients undergoing MIDCAB surgery.

Comparison of perioperative analgesia using the infiltration of the surgical site with ropivacaine alone and in combination with meloxicam in cats undergoing ovariohysterectomy.

BACKGROUND: Infiltration of the surgical site with local anesthetics combined with nonsteroidal anti-inflammatory drugs may play an important role in improving perioperative pain control. This prospective, randomized, blinded, controlled clinical trial aimed to evaluate intraoperative isoflurane requirements, postoperative analgesia, and adverse events of infiltration of the surgical site with ropivacaine alone and combined with meloxicam in cats undergoing ovariohysterectomy. Forty-five cats premedicated with acepromazine/meperidine and anesthetized with propofol/isoflurane were randomly distributed into three treatments (n = 15 per group): physiological saline (group S), ropivacaine alone (1 mg/kg, group R) or combined with meloxicam (0.2 mg/kg, group RM) infiltrated at the surgical site (incision line, ovarian pedicles and uterus). End-tidal isoflurane concentration (FE'ISO), recorded at specific time points during surgery, was adjusted to inhibit autonomic responses to surgical stimulation. Pain was assessed using an Interactive Visual Analog Scale (IVAS), UNESP-Botucatu Multidimensional Composite Pain Scale (MCPS), and mechanical nociceptive thresholds (MNT) up to 24 h post-extubation. Rescue analgesia was provided with intramuscular morphine (0.1 mg/kg) when MCPS was ≥6. RESULTS: Area under the curve (AUC) of FE'ISO was significantly lower (P < 0.0001) in the RM (17.8 ± 3.1) compared to S (23.1 ± 2.2) and R groups (22.8 ± 1.1). Hypertension (systolic arterial pressure > 160 mmHg) coinciding with surgical manipulation was observed only in cats treated with S and R (4/15 cats, P = 0.08). The number of cats receiving rescue analgesia (4 cats in the S group and 1 cat in the R and RM groups) did not differ among groups (P = 0.17). The AUC of IVAS, MCPS and MNT did not differ among groups (P = 0.56, 0.64, and 0.18, respectively). Significantly lower IVAS pain scores were recorded at 1 h in the RM compared to the R and S groups (P = 0.021-0.018). There were no significant adverse effects during the study period. CONCLUSIONS: Local infiltration with RM decreased intraoperative isoflurane requirements and resulted in some evidence of improved analgesia during the early postoperative period. Neither R nor RM infiltration appeared to result in long term analgesia in cats undergoing ovariohysterectomy.

[Ropivacaine withdrawal syndrome: a case report]. / Síndrome de abstinência de ropivacaína: relato de caso.

INTRODUCTION AND OBJECTIVES: Ropivacaine is a long-acting local anesthetic that causes prolonged anesthesia and is beneficial for a wide variety of surgeries. Systemic toxicity has been reported after usage of high dose ropivacaine or inadvertent intravascular administration. We report a case of ropivacaine withdrawal, which to our knowledge has not been previously described in the literature. CASE REPORT: The patient presented to our department with uncontrolled belt-like upper-abdominal pain, self-rated as a 9/10 on the numeric rating scale. We decided to use continuous epidural analgesia with ropivacaine through a multi-port epidural catheter. Pain was well controlled for one month without significant adverse effects. However, ropivacaine unexpectedly ran out and two hours later the patient developed agitation, generalized tremor, tachycardia, and tachypnea. These symptoms resolved 30 minutes after reinitiating epidural ropivacaine. DISCUSSION: Our hypothesis of ropivacaine withdrawal was related to the timing of symptoms in relation to drug administration over two episodes. The possible mechanism of the observed withdrawal syndrome is upregulation of voltage-gated sodium channels after prolonged inhibition, resulting in increase in sodium influx and genetic variation.

Effects of quadratus lumborum block regional anesthesia on postoperative pain after colorectal resection: a randomized controlled trial.

INTRODUCTION: Postoperative pain following colorectal surgery is associated with a significant use of opioids. Recently, regional anesthesia, such as the posterior quadratus lumborum block (QL2), has been proposed to improve pain relief and reduce opioid use. However, the benefit of the QL2 on postoperative pain control remains controversial. METHODS: We conducted a randomized controlled trial of patients undergoing colorectal surgery at the CHU de Québec-Université Laval. Patients were randomized to regional QL2 anesthesia with 150 mg of ropivacaine combined with standard analgesia or to QL2 with a sham intervention and standard analgesia. Our primary outcome was postoperative opioid administration at 24 h. Secondary outcomes included opioid administration in the post-anesthesia care unit (PACU), at 48 h and at hospital discharge, postoperative pain scores, delay in resumption of intestinal transit, nausea and vomiting, and hospital length of stay. RESULTS: A total of 62 patients were enrolled from November 2017 to February 2018. QL2 regional anesthesia compared with a sham intervention was not associated with a reduction in postoperative morphine dose equivalent (100.2 mg, 95% CI 68.9-131.5 versus 88.7 mg, 95% CI 59.3-118.0, p = 0.81, respectively). Compared to QL2 regional anesthesia, postoperative pain scores in the control group were lower although statistical significance was not consistent for all postoperative time points. Other secondary outcomes were comparable between both groups. CONCLUSION: We did not observe a reduction in postoperative opioid administration at 24 h with a posterior quadratus lumborum block regional anesthesia in patients undergoing elective colorectal surgery.

Local Anesthetic Systemic Toxicity Following General and Epidural Anesthesia in A patient with a History of Muscle Relaxant-induced Anaphylaxis.

We here report that a 71-year-old Japanese woman with a history of anaphylaxis induced by muscle relaxants had local anesthetic systemic toxicity (LAST) following an abdominal surgery under general anesthesia with combined spinal-epidural anesthesia without muscle relaxants. The total dosages of local anesthetics reached 0.67 mg/kg of ropivacaine and 11.5 mg/kg of lidocaine over 12.5 h to obtain sufficient muscle relaxation for surgery. Regional anesthesia is useful in cases in which muscle relaxants are to be avoided during a surgery. However, especially for a patient with risk factors and prolonged surgery, precautions should be taken to prevent LAST.