An Observational Study of the Pharmacokinetics of Surgeon-Performed Intercostal Nerve Blockade With Liposomal Bupivacaine for Posterior-Lateral Thoracotomy Analgesia

Combined pectoralis and serratus anterior plane blocks with or without liposomal bupivacaine for minimally invasive thoracic surgery: A randomized clinical trial

BACKGROUND

Minimally invasive thoracic surgery is associated with substantial pain that can impair pulmonary function. Fascial plane blocks may offer a favorable alternative to opioids, but conventional local anesthetics provide a limited duration of analgesia. We therefore tested the primary hypothesis that a mixture of liposomal bupivacaine and plain bupivacaine improves the overall benefit of analgesia score (OBAS) during the first three postoperative days compared to bupivacaine alone. Secondarily, we tested the hypotheses that liposomal bupivacaine improves respiratory mechanics, and decreases opioid consumption.

METHODS

Adults scheduled for robotically or video-assisted thoracic surgery with combined ultrasound-guided pectoralis II and serratus anterior plane block were randomized to bupivacaine or bupivacaine combined with liposomal bupivacaine. OBAS was measured on postoperative days 1-3 and was analyzed with a linear mixed regression model. Postoperative respiratory mechanics were estimated using a linear mixed model. Total opioid consumption was estimated with a simple linear regression model.

RESULTS

We analyzed 189 patients, of whom 95 were randomized to the treatment group and 94 to the control group. There was no significant treatment effect on total OBAS during the initial three postoperative days, with an estimated geometric mean ratio of 0.93 (95% CI: 0.76, 1.14; p = 0.485). There was no observed treatment effect on respiratory mechanics, total opioid consumption, or pain scores. Average pain scores were low in both groups.

CONCLUSIONS

Liposomal bupivacaine did not improve OBAS during the initial postoperative three days following minimally invasive thoracic procedures. Furthermore, there was no improvement in respiratory mechanics, no reduction in opioid consumption, and no decrease in pain scores. Thus, the data presented here does not support the use of liposomal bupivacaine over standard bupivacaine to enhance analgesia after minimally invasive thoracic surgery.

SUMMARY STATEMENT

For minimally invasive thoracic procedures, addition of liposomal bupivacaine to plain bupivacaine for thoracic fascial plane blocks does not improve OBAS, reduce opioid requirements, improve postoperative respiratory mechanics, or decrease pain scores.

CYP3A4 gene expression discloses individual differences in postoperative pain susceptibility and drug treatment response in patients with lung cancer

This study investigates the influence of CYP3A4 gene polymorphisms on postoperative pain sensitivity and analgesic response in lung cancer patients undergoing intercostal nerve block with local anesthetics. Sixty patients (ages 31-74) undergoing thoracoscopic lung cancer surgery were enrolled and divided into two groups based on CYP3A4 gene expression level: Group I (high CYP3A4) and Group II (low CYP3A4). Postoperative pain was assessed using the Visual Analogue Scale (VAS), and patient-controlled intravenous analgesia (PCIA) pump usage, ECG ST-T segment changes, complications, hospital stay, and costs were recorded. Results showed significantly higher VAS scores, PCIA usage, ST-T depression, complications, longer hospital stay, and higher costs in Group I compared to Group II (P < 0.05). These findings suggest that higher CYP3A4 expression is associated with increased postoperative pain, complications, and healthcare cost. According to CYP3A4 gene expression activity, which was determined before surgery, patients with low enzyme activity metabolized local anesthetics slowly, which resulted in better analgesic effect and a longer duration of intercostal nerve block anesthesia. Owing to the impact of CYP3A4 gene expression on local anesthetic metabolism, precise intercostal nerve block anesthesia and individualized pain treatment plans could be formulated for patients undergoing radical thoracoscopic surgery for lung cancer. This may accelerate postoperative recovery from lung cancer and reduce both the length of hospital stay and hospitalization costs.

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.

Plasma bupivacaine levels (total and free/unbound) during epidural infusion in liver resection patients: a prospective, observational study

INTRODUCTION

Liver resection patients may be at an increased risk of local anesthetic (LA) toxicity because the liver is essential for metabolizing LA and producing proteins (mainly α1-acid glycoprotein (AAG)) that bind to it and reduce the free (and pharmacologically active/toxic) levels in circulation. The liver resection itself, manipulation during surgery, and pre-existing liver disease may all interfere with normal hepatic protein synthesis and result in an attenuation of the increased AAG (a positive acute-phase protein) that normally occurs postoperatively. The purpose of this study was to determine whether the AAG response is attenuated postoperatively following liver resection and whether patients approach toxicity thresholds with continuous postoperative epidural infusion of bupivacaine.

METHODS

Prospective, observational study with blood drawn preoperatively, in the postanesthetic care unit, on postoperative day (POD) 2, and prior to discontinuation of epidural analgesia on POD3/POD4. Plasma was analyzed for total and unbound bupivacaine via liquid chromatography-mass spectrometry and AAG via ELISA. Signs/symptoms of local anesthetic systemic toxicity (LAST), pain, and sedation scores were also recorded.

RESULTS

For the 19 patients completed, total plasma bupivacaine was correlated with total administered, but unbound levels were not associated with the total administered. Unlike non-hepatectomy surgery where unbound LA plasma levels remain stable (or decrease) with continuous postoperative epidural administration, we observed an overall increase. Several patients approached toxicity thresholds and 47% reported at least one symptom of LAST, but no epidurals were discontinued because of LAST. In contrast to the AAG response reported following major non-liver surgery where AAG levels increase twofold, we observed a reduction until POD2 and the magnitude was proportional to resection weight.

DISCUSSION

Our results are supported by the literature in suggesting that major liver resection patients may be at an increased vulnerability for LAST. Factors such as the extent of liver disease, resection and intraoperative blood loss should be considered when using continuous postoperative epidural infusion of bupivacaine and vigilance should be used in monitoring, for signs/symptoms of LAST, even for those subtle and non-specific. Future research will be required to verify these findings.

TRIAL REGISTRATION NUMBER

NCT03145805.

A multimodal protocol utilizing liposomal bupivacaine rib blocks leads to opioid reduction in patients undergoing the Nuss procedure

Background

A major challenge associated with the Nuss procedure for pectus excavatum repair is postoperative pain control. Early Recovery Program (ERP) protocols for the Nuss procedure are becoming common, but there is a paucity of experience using liposomal bupivacaine (LB), a long-acting local anesthetic, for rib blocks in this setting. We investigated whether a protocol utilizing LB rib blocks decreased opioid use after the Nuss procedure while achieving equivalent pain control.

Methods

All adolescent patients undergoing the Nuss procedure at our institution between January 2013 and January 2021 were included. Patients were divided into a pre-intervention cohort (n=15), a transition cohort (n=4), and a post-intervention cohort (n=13). Patients in all groups received scheduled acetaminophen and non-steroidals postoperatively. The pre-intervention cohort received an opioid patient-controlled analgesia (PCA) pump postoperatively, with a transition to oral opiates. The transition and post-intervention cohorts received scheduled gabapentin in addition to intraoperative bilateral rib blocks with longer-acting local anesthetic. Rib blocks were performed using 0.25% Bupivacaine in the pre-intervention group. In the transition group, epinephrine (1 mg/kg) was added to 0.25% bupivacaine for the rib block. Following approval in patients aged 13–18 years, 1.3% LB (2.25 mg/kg) was given for a rib block in the post-intervention cohort.

Results

Demographic and clinical variables were equivalent in all groups. Post-intervention patients received 90% fewer opioids [median morphine equivalent (MME) mg/kg] compared to the pre-intervention cohort (0.8 vs. 8.2 MME mg/kg, P<0.0001), with no significant difference in pain scores between groups. Hospital length of stay was decreased among the intervention cohort (3 vs. 4 days, P=0.002).

Conclusions

Significant decreases in opioid use and length of stay after the Nuss procedure were achieved by the implementation of a multimodal ERP for pain management, without increase in patient-reported pain scores.

Multimodal opioid-sparing pain management after lung transplantation and the impact of liposomal bupivacaine intercostal nerve block

Opioid analgesics are commonly used post-lung transplant, but have many side effects and are associated with worse outcomes. We conducted a retrospective review of all lung transplant recipients who were treated with a multimodal opioid-sparing pain protocol. The use of liposomal bupivacaine intercostal nerve block was variable due to hospital restrictions. The primary objective was to describe opioid requirements and patient-reported pain scores early post-lung transplant and to assess the impact of intraoperative liposomal bupivacaine intercostal nerve block. We treated 64 lung transplant recipients with our protocol. Opioid utilization decreased to a mean of 43 milligram oral morphine equivalents by postoperative day 4. Median pain scores peaked at 4 on postoperative day 1 and decreased thereafter. Only three patients were discharged home with opioids, all of whom were taking opioid agonist therapy pre-transplant for opioid use disorder. Patients who received liposomal bupivacaine intercostal nerve block in the operating room had a significant reduction in opioid consumption over postoperative day 1 through 4 (228 mg vs. 517 mg, P= .032). A multimodal opioid-sparing pain management protocol is feasible and resulted in weaning of opioids prior to hospital discharge.

Liposomal Bupivacaine Versus Bupivacaine/Epinephrine Intercostal Nerve Block as Part of an Enhanced Recovery After Thoracic Surgery (ERATS) Care Pathway for Robotic Thoracic Surgery

OBJECTIVES

To examine how postoperative pain control after robotic thoracoscopic surgery varies with liposomal bupivacaine (LipoB) versus 0.5% bupivacaine/1:200,000 epinephrine (Bupi/Epi) intercostal nerve blocks within the context of an enhanced recovery after thoracic surgery (ERATS) protocol.

DESIGN

A retrospective analysis of a prospectively maintained database of patients undergoing robotic thoracoscopic procedures between September 1, 2018 and October 31, 2019 was conducted.

SETTING

University of Miami, single-institutional.

PARTICIPANTS

Patients.

INTERVENTIONS

Two hundred fifty-two patients had either LipoB intercostal nerve blocks (n = 129) or Bupi/Epi intercostal nerve blocks (n = 123) when undergoing robotic thoracic surgery.

MEASUREMENTS AND MAIN RESULTS

Comparative analysis of patient-reported pain levels, in-hospital and post-discharge opioid requirements, 90-day operative complications, length of hospital stay, and hospital costs was performed. Data were stratified to either anatomic lung resection or pulmonary wedge resection/mediastinal-pleural procedures. Bupi/Epi patients reported significantly more acute postoperative pain than LipoB patients, which correlated with higher in-hospital and post-discharge opioid requirements. There were no differences in postoperative complications, length of hospital stay, or hospital costs between the two groups.

CONCLUSIONS

As part of an ERATS protocol, infiltration of intercostal spaces and surgical wounds with LipoB for robotic thoracoscopic procedures afforded better postoperative subjective pain control and decreased opioid requirements without an increase in hospital costs as compared with use of Bupi/Epi.

Liposomal Bupivacaine Versus Bupivacaine Hydrochloride for Intercostal Nerve Blockade in Minimally Invasive Thoracic Surgery

OBJECTIVES

The objective of this study was to compare the effects of liposomal bupivacaine (Lipo-B) and bupivacaine hydrochloride (B-HCl), in the presence of multimodal analgesia, on postoperative analgesia and opioid consumption in minimally invasive thoracic surgery (MITS) lobectomy.

DESIGN

Retrospective observational cohort study.

SETTING

Tertiary care cancer center.

PARTICIPANTS

A total of 60 patients who underwent MITS lobectomy and received intercostal nerve blockade (ICNB) with either 0.66% Lipo-B (n = 29) or 0.5% B-HCl (n = 31).

INTERVENTIONS

All patients received intravenous patient-controlled analgesia for the first 12 hours postoperatively, followed by opioids and nonsteroidal anti-inflammatory drugs as needed.

MEASUREMENTS AND MAIN RESULTS

Perioperative opioid and nonopioid consumption and pain scores were compared between groups at 12-hour intervals for the first 72 hours. Between the two groups, there were no statistically significant differences in demographic characteristics, intraoperative (p = 0.46) and postoperative opioid consumption, Richmond Agitation-Sedation Scale scores and pain scores upon postanesthesia care unit arrival and after four hours, length of postanesthesia care unit stay (p = 0.84), or length of hospital stay (p = 0.55). Both groups received intra- and postoperative multimodal analgesia.

CONCLUSIONS

In this cohort, no differences in opioid consumption or pain scores were observed in the immediate postoperative period following MITS lobectomy between patients given ICNB with Lipo-B and those given ICNB with B-HCl in the presence of multimodal analgesia.