Pharmacokinetics of ropivacaine in patients with chronic end-stage liver disease

Anesthesia in patients with chronic liver disease: An updated review

Anesthesia in chronic liver disease patients can be challenging because of the medications given or interventions performed and their effects on liver physiology. Also, the effects of liver disease on coagulation and metabolism should be considered carefully. This review focuses on anesthesia in patients with different chronic liver disease stages. A literature search was performed for Scopus and PubMed databases for articles discussing different types of anesthesia in patients with chronic liver disease, their safety, usage, and risks. The choice of anesthesia is of crucial importance. Regional anesthesia, especially neuroaxial anesthesia, may benefit some patients with liver disease, but coagulopathy should be considered. Regional anesthesia provides optimum intraoperative relaxation and analgesia that extends to the postoperative period while avoiding the side effects of intravenous anesthetics and opioids. Pharmacodynamics and pharmacokinetics of anesthetic medications must guard against complications related to overdose or decreased metabolism. The choice of anesthesia in chronic liver disease patients is crucial and could be tailored according to the degree of liver compensation and the magnitude of the surgical procedure.

Comparison of postoperative analgesic effects of erector spinae plane block and quadratus lumborum block in laparoscopic liver resection: study protocol for a randomized controlled trial

BACKGROUND

Compared with open surgery, laparoscopic liver resection is a minimally invasive surgical technique. However, a number of patients experience moderate-to-severe postoperative pain after laparoscopic liver resection. This study aims to compare the postoperative analgesic effects of erector spinae plane block (ESPB) and quadratus lumborum block (QLB) in patients undergoing laparoscopic liver resection.

METHODS

One hundred and fourteen patients undergoing laparoscopic liver resection will be randomly allocated to three groups (control, ESPB, or QLB) in a 1:1:1 ratio. In the control group, participants will receive systemic analgesia consisting of regular NSAIDs and fentanyl-based patient-controlled analgesia (PCA) according to the institutional postoperative analgesia protocol. In the two experimental groups (ESPB or QLB group), the participants will receive preoperative bilateral ESPB or bilateral QLB in addition to systemic analgesia according to the institutional protocol. ESPB will be performed at the 8th thoracic vertebra level with ultrasound guidance before surgery. QLB will be performed in the supine position on the posterior plane of the quadratus lumborum with ultrasound guidance before surgery. The primary outcome is cumulative opioid consumption 24 h after surgery. Secondary outcomes are cumulative opioid consumption, pain severity, opioid-related adverse events, and block-related adverse events at predetermined time points (24, 48, and 72 h after surgery). Differences in plasma ropivacaine concentrations in the ESPB and QLB groups would be investigated, and the quality of postoperative recovery among the groups will be compared.

DISCUSSION

This study will reveal the usefulness of ESPB and QLB in terms of postoperative analgesic efficacy and safety in patients undergoing laparoscopic liver resection. Additionally, the study results will provide information on the analgesic superiority of ESPB versus QLB in the same population.

TRIAL REGISTRATION

Prospectively registered with the Clinical Research Information Service on August 3, 2022; KCT0007599.

Quadratus lumborum blocks for abdominal transplant surgeries at UPMC Children's Hospital of Pittsburgh-A five year experience

BACKGROUND

Adequate perioperative analgesia for pediatric abdominal transplant surgery is essential for patient recovery. However, the risks of commonly used medications such as hepatotoxicity, nephrotoxicity, bleeding concerns, and poor graft results with opioids limit pain management in this population. Thoracic epidural, continuous erector spinae plane, and type-1 quadratus lumborum blocks (QLBs) have been described and utilized in the adult population in this setting. The safety and benefits of regional anesthetic techniques in pediatrics have been widely documented for different types of procedures except pediatric abdominal transplantation, where data remains scarce. Our primary goal was to determine if QLBs provided adequate perioperative analgesia when part of a multimodal approach. Secondary objectives were to examine complications and effects on the intensive care unit (ICU) and hospital stay.

METHODS

We performed a retrospective, observational study of pediatric patients who underwent abdominal transplant surgeries at the University of Pittsburgh Medical Center Children's Hospital of Pittsburgh from January 2015 to July 2021 and received a single injection QLB for pain control. Data collected included: demographics, nerve block characteristics, perioperative opioid consumption, use of non-opioid analgesia, daily pain scores, and hospital and ICU stay.

RESULTS

Forty-two patients met the inclusion criteria for our study. Our results suggest that QLBs decrease opioid consumption, facilitate early extubation, prevent reintubation in the ICU, and reduce ICU and hospital stay.

CONCLUSIONS

QLB is feasible and can be used as a multimodal approach for postoperative pain control in pediatric solid organ transplantation.

Local anesthetic systemic toxicity: A narrative review for emergency clinicians

INTRODUCTION

Emergency clinicians utilize local anesthetics for a variety of procedures in the emergency department (ED) setting. Local anesthetic systemic toxicity (LAST) is a potentially deadly complication.

OBJECTIVE

This narrative review provides emergency clinicians with the most current evidence regarding the pathophysiology, evaluation, and management of patients with LAST.

DISCUSSION

LAST is an uncommon but potentially life-threatening complication of local anesthetic use that may be encountered in the ED. Patients at extremes of age or with organ dysfunction are at higher risk. Inadvertent intra-arterial or intravenous injection, as well as repeated doses and higher doses of local anesthetics are associated with greater risk of developing LAST. Neurologic and cardiovascular manifestations can occur. Early recognition and intervention, including supportive care and intravenous lipid emulsion 20%, are the mainstays of treatment. Using ultrasound guidance, aspirating prior to injection, and utilizing the minimal local anesthetic dose needed are techniques that can reduce the risk of LAST.

CONCLUSIONS

This focused review provides an update for the emergency clinician to manage patients with LAST.

Local anesthetics for the Nephrologist

Several specialists in medicine use local anesthetics. In patients with kidney disease, these agents are used during catheter insertions for hemodialysis and peritoneal dialysis, arteriovenous fistula and graft procedures, kidney transplantation, parathyroidectomy, kidney biopsies, and dental and skin procedures. Patients on chronic hemodialysis use a topical application prior to use of needles for arteriovenous fistula cannulation before starting dialysis. They are also used to manage acute and chronic pain conditions, in regional nerve blockade and in multi-modal enhanced recovery protocols. Despite their frequent use by both physicians and patients, data on the use of local anesthetics in patients with kidney impairment are not well reported. This review will summarize the use of local anesthetics in chronic kidney disease, describe their pharmacology and the impact of lower estimated glomerular filtration rate on their pharmacokinetics, and suggest dose regulation in those with kidney dysfunction.

Comparison of Analgesic Efficacy of Erector Spinae Plane Block and Posterior Quadratus Lumborum Block in Laparoscopic Liver Resection: A Randomized Controlled Trial

Purpose

Ultrasound-guided fascial plane blocks, including the erector spinae plane (ESP) and quadratus lumborum (QL) blocks, provide effective postoperative abdominal analgesia. However, there is limited evidence on the analgesic efficacy of ESP and QL blocks after liver surgery. Therefore, we aimed to compare the cumulative opioid consumption between the ESP and QL blocks in patients with hepatocellular carcinoma undergoing laparoscopic liver resection.

Patients and Methods

Eighty-eight patients scheduled to undergo laparoscopic liver resection were randomized to receive bilateral single injection of ESP block at T8 (ESP group) or bilateral single injection of posterior QL block (QL group; 20 mL of 0.375% ropivacaine for each side, ie, total 150 mg of ropivacaine), in addition to intravenous (IV) fentanyl patient-controlled analgesia and multimodal analgesia. The primary outcome was cumulative opioid consumption over the first 24 h, expressed as IV morphine equivalents. Secondary outcomes included serial plasma ropivacaine concentrations, pain scores, time to first flatus, and Quality of Recovery-15 scores.

Results

Eighty-five patients were analyzed (ESP group, n = 42; QL group, n = 43). Cumulative 24-h opioid consumption was similar between the ESP and QL groups (41.4 ± 22.6 mg vs 44.2 ± 20.0 mg, mean difference (QL-ESP), 2.8 mg, 95% confidence interval, −6.4 to 12 mg, p > 0.99). There were no significant differences in resting pain scores at 24, 48 and 72 h postoperatively or recovery outcomes. The peak plasma ropivacaine concentration 30 min after injection was significantly higher in the ESP group (1.5 ± 0.3 µg/mL) than in the QL group (1.3 ± 0.5 µg/mL, p = 0.035); however, both were lower than the arterial threshold value of systemic toxicity (4.3 µg/mL).

Conclusion

ESP and QL blocks provided similar postoperative analgesia in patients undergoing laparoscopic liver resection.

Liver and Biliary Disease of Pregnancy and Anesthetic Implications: A Review

Liver and biliary disease complicates pregnancy in varying degrees of severity to the mother and fetus, and anesthesiologists may be asked to assist in caring for these patients before, during, and after birth of the fetus. Therefore, it is important to be familiar with how different liver diseases impact the pregnancy state. In addition, knowing symptoms, signs, and laboratory markers in the context of a pregnant patient will lead to faster diagnosis and treatment of such patients. This review article discusses changes in physiology of parturients, patients with liver disease, and parturients with liver disease. Next, general treatment of parturients with acute and chronic liver dysfunction is presented. The article progresses to specific liver diseases with treatments as they relate to pregnancy. And finally, important aspects to consider when anesthetizing parturients with liver disease are discussed.

Intraperitoneal local anaesthesia for post-operative pain management in patients undergoing laparoscopic colorectal surgery: a systematic review and meta-analysis

INTRODUCTION

Intraperitoneal instillation of local anaesthetic agents has been reported as an effective adjunct to pain management and early functional recovery in colorectal surgery. Laparoscopic colorectal resection (LCR) is considered as the gold standard approach to resect benign and malignant lesions of the colon and rectum due to the advantages of reduced pain score, quicker recovery, and shorter hospitalization. The objective of this study is to systematically analyze the published RCTs evaluating the effectiveness of intraperitoneal local anesthetic (IPLA) instillation versus standard analgesia in patients undergoing LCR.

EVIDENCE ANALYSIS

Electronic databases such as Embase, Medline, PubMed, PubMed Central and the Cochrane library pertaining to the use of IPLA infiltration after LCR were systematically reviewed using the principles of meta-analysis.

EVIDENCE SYNTHESIS

Five RCTs on 292 patients undergoing LCR were either given IPLA or standard post-operative analgesia. In the random-effects model analysis using the statistical software Review Manager, statistically 2-4 hours pain score (Standardized mean difference (SMD), -1.72; 95% CI, -2.62, -0.81; z = 3.71; P = 0.0002) was significantly ower in the IPLA group. The 12 hours post-operative pain score (P = 0.23) was also lower in the IPLA group but failed to reach the statistical significance. Opioid analgesia requirement was lower in the IPLA group (SMD -7.60; 95% CI, -11.21, -3.90; z = 4.12; P = 0.0001) but the time to flatus, length of stay and the frequency of nausea/vomiting were statistically similar in both groups.

CONCLUSIONS

IPLA instillation is an effective modality to reduce the post-operative pain score and lower the opioid analgesic requirements in patients undergoing LCR without influencing the time to first flatus, length of stay, and post-operative nausea/vomiting.

Inadvertent mental excitement after ultrasound-guided bilateral thoracic paravertebral block: a case report

Background

Bilateral Paravertebral block has been used successfully for postoperative pain relief in thoracic, abdominal, and pelvic regions. Despite the need for relatively large doses of local anaesthetics, there are few reports of systemic toxicity. Here we reported a case of local anaesthetic toxicity after ultrasound-guided bilateral thoracic paravertebral block before general anaesthesia leading to mental. To our knowledge, the onset of this patient has never been reported previously, and we will discuss the potential risk factors and preventive measures for such patients in the future.

Case information

A 38-year-old female patient presented for elective open resection of liver tumor, when bilateral 7th thoracic (T7) paravertebral blocks were performed under the guidance of ultrasound with 0.5% ropivacaine (3 mg/kg) in the anesthesia preparation area. After 20 minutes, the patient suddenly became extremely excited and requested to suspend the operation, because Guanyin Bodhisattva just told her that the operation would put her life in danger.

Conclusion

Although the dose of ropivacaine was up to 3 mg/kg for lumbar epidural, or 4.3 mg/kg for major nerve block based on the manufacturer's recommendation, we believe that the bolus dosage of 0.5% ropivacaine 3 mg/kg was high for bilateral thoracic paravertebral block in this patient.

Predicting Drug Binding to Human Serum Albumin and Alpha One Acid Glycoprotein in Diseased and Age Patient Populations

Plasma protein binding, namely the fraction unbound (f_u), can be an important determinant of the disposition and response of drugs. The primary objective of this study was to predict f_u values of 183 drugs utilizing either a single binding protein model, where the predominant binding protein had been established, or a multiple binding protein model (MBPM), where the relative binding contribution of human serum albumin (HSA) or alpha 1 acid glycoprotein (AAG) is known. Mean protein concentrations, dependent on disease or age, were used to account for changes in f_u. A simple scaling approach for binding protein concentration was employed to account for quantitative changes in molar concentrations of either HSA or AAG in their respective conditions. The MBPM predictive model works best if the relative binding contribution of HSA and AAG is known, and a scaler for the change in protein concentration can be adjusted accordingly. The value of MBPM was most evident when considering reported changes in lidocaine binding because of increasing AAG concentration in response to trauma. The present approach enhances the ability to predict f_u in diseased and age populations because of quantitative changes in major binding proteins.

Interaction between anesthetic conditioning and ischemic preconditioning on metabolic function after hepatic ischemia-reperfusion in rabbits

BACKGROUND

Both anesthetic-induced and ischemic preconditioning are protective against hepatic ischemia-reperfusion injury. However, the effects of these preventive methods on the metabolic function remain to be elucidated. We investigated the anesthetic conditioning and ischemic preconditioning on the metabolic function of the rabbit model of hepatic ischemia-reperfusion.

METHODS

After approval by the institutional animal care and use committee, 36 Japanese White rabbits underwent partial hepatic ischemia for 90 min either under sevoflurane or propofol anesthesia. All the rabbits underwent 90 min of hepatic ischemia, and half of the rabbits in each group underwent additional 10-min ischemia and 10-min reperfusion before index ischemia. Hepatic microvascular blood flow was intermittently measured during reperfusion period, and galactose clearance, serum aminotransferase activities, and lactate concentrations were determined 180 min after reperfusion.

RESULTS

Neither anesthetic conditioning with sevoflurane nor ischemic preconditioning altered hepatic microvascular blood flow during reperfusion and serum transaminase activities after reperfusion. However, galactose clearance of reperfused liver was significantly higher under sevoflurane anesthesia than propofol (0.016 ± 0.005/min vs. 0.011 ± 0.004/min). Statistically significant interaction between anesthetic choice and application of ischemic preconditioning suggests that the ischemic preconditioning is selectively protective under propofol anesthesia. Increase of blood lactate concentration was significantly suppressed under sevoflurane anesthesia compared to propofol (1.5 ± 0.8 vs. 3.9 ± 1.4 mmol/l) without any statistically significant interaction with the application of ischemic preconditioning.

CONCLUSION

Sevoflurane attenuated the decrease of galactose clearance and increase of the blood lactate after reperfusion compared to propofol. Application of ischemic preconditioning was significantly protective under propofol anesthesia.

Analgesia with continuous wound infusion of local anesthetic versus saline: Double-blind randomized, controlled trial in hepatectomy

BACKGROUND

Surgical wound is source of pain in hepatectomy with laparotomy. Continuous wound infusion of ropivacaine may provide effective analgesia.

METHODS

This prospective, randomized trial, patients scheduled for hepatectomy received a 48-h preperitoneal continuous wound infusion of either 0.23% ropivacaine or 0.9% saline at 5 ml/h. Primary endpoint was 48 h morphine consumption.

RESULTS

53 patients included in the ropivacaine group and 46 in the saline group. Morphine consumption was 24.63 mg in the ropivacaine group, and 26.78 mg (p = 0.669) in the saline group. Pain was comparable between groups and there were no differences in solid food intake, ambulation, or length of hospital stay. No local or systemic complications were recorded.

CONCLUSIONS

Continuous wound infusion with ropivacaine is safe, but it neither reduced morphine consumption nor enhanced recovery in patients undergoing hepatectomy. Success of enhanced recovery in hepatectomy is not influenced by the analgesic regimen if pain is well controlled.

Association of CYP450 single nucleotide polymorphisms with the efficacy of epidural ropivacaine during mastectomy

BACKGROUND

Ropivacaine is frequently used for local anesthesia in the clinic and is metabolized by cytochrome P450 (CYP450) in the liver. CYP450 polymorphisms may alter the therapeutic efficacy of drugs in patients. In this study, we selected six CYP450 polymorphisms from the dbSNP and HapMap databases, using a combination of functional analysis and Tag SNP strategies and examined these polymorphisms for association with the efficacy of epidural ropivacaine in patients during mastectomy.

METHODS

A total of 256 patients with breast cancer received thoracic epidural anesthesia with ropivacaine for elective mastectomy with axillary lymph node clearance. Blood samples from patients were genotyped using the SNaPshot method.

RESULTS

We found that patients with rs11636419 AG and GG genotypes required lower doses of epidural ropivacaine than patients with the AA genotype (corrected P = 0.024 and P < 0.001, respectively). Similarly, patients with rs17861162 CG and GG genotypes required lower doses of epidural ropivacaine than those with the CC genotype (corrected P = 0.018 and P < 0.001, respectively). There was no statistically significant association between the other four single nucleotide polymorphisms (SNPs) and total or mean ropivacaine dose, the onset of ropivacaine, or the initial dose of lidocaine.

CONCLUSIONS

Our present data demonstrate that CYP1A2 SNPs rs11636419 and rs17861162 alter the sensitivity of epidural ropivacaine in patients undergoing breast cancer surgery. As such, detection of these two CYP1A2 SNPs may aid in the development of effective personalized treatments for breast cancer patients.

Pharmacokinetics of ropivacaine in patients with chronic renal failure

BACKGROUND

As ropivacaine and its metabolites are excreted by the kidneys, we studied their disposition in subjects with renal dysfunction.

METHODS

Twenty patients with moderate or severe renal insufficiency and 10 healthy volunteers received ropivacaine 1 mg kg(-1) i.v. over 30 min. The concentrations of ropivacaine and its main metabolites, pipecoloxylidide (PPX) and 3-hydroxy-ropivacaine, were measured in plasma and urine for 16-48 h. The relationship between pharmacokinetic parameters and creatinine clearance (CL(CR)) was assessed. A model for estimating non-renal clearance of a metabolite of ropivacaine is described.

RESULTS

Renal dysfunction had little or no influence on the pharmacokinetics of ropivacaine. The median plasma concentrations of unbound ropivacaine were similar in uraemic and non-uraemic subjects. Renal clearance of PPX correlated significantly with CL(CR) (R(2)=0.81). Lack of correlation between total PPX exposure, expressed as area under the total plasma concentration-time curve from zero to infinity, and CL(CR) suggests that the clearance of PPX also includes non-renal elimination. However, in two uraemic patients, there was increased exposure to PPX resulting from low non-renal elimination.

CONCLUSIONS

The pharmacokinetics of ropivacaine is not affected by renal failure. Although the renal clearance of PPX correlates with CL(CR), non-renal elimination seems to compensate for reduced renal clearance in most patients. PPX may accumulate in plasma during long-term postoperative infusions, in particular in patients with co-existing low non-renal elimination. Systemic toxicity is still unlikely because PPX is markedly less toxic than ropivacaine.

The effect of a long term epidural infusion of ropivacaine on CYP2D6 activity

BACKGROUND

Ropivacaine and one of its metabolites, pipecoloxylidide, inhibit CYP2D6 in. human liver microsomes in vitro with K(i) values of 5 microM (1.4 mg/L) and 13 microM (3.6 mg/L), respectively. We investigated the effect of a 50 h continuous epidural infusion of ropivacaine 2 mg/mL at a rate of 14 mL/h on CYP2D6 activity.

METHODS

Nineteen patients (41-85 yr) undergoing hip or knee replacement, all extensive metabolizers with respect to CYP2D6 activity, were included. Medications known to inhibit or be metabolized by CYP2D6, or known to be strong inhibitors/inducers of CYP1A2 or CYP3A4 were not allowed. Patients received 10 mg debrisoquine (a marker for CYP2D6 activity) before surgery and after 40 h epidural infusion. The metabolic ratio (MR) for debrisoquine hydroxylation was calculated as the amount of debrisoquine/amount of 4-OH-debrisoquine excreted in 0-10 h urine.

RESULTS

The median (range) of MR before and after ropivacaine were 0.54 (0.1-3.4) and 1.79 (0.3-6.7), respectively. The Hodges Lehman estimate of the ratio MR after/MR before ropivacaine was 2.2 with a 95% confidence interval 1.9-2.7 (P < 0.001).

CONCLUSION

A continuous epidural infusion of ropivacaine inhibits CYP2D6 activity in patients who are extensive metabolizers resulting in a twofold increase in the MR for debrisoquine hydroxylation. However, since none of the patients was converted into a functional poor metabolizer (MR >12.6), the effect on the metabolism of other drugs metabolized by CYP2D6 is unlikely to be of major clinical importance.