A Randomized Controlled Trial of Liposomal Bupivacaine Parasternal Intercostal Block for Sternotomy

Advances in the use of local anesthetic extended-release systems in pain management

Pain management remains among the most common and largely unmet clinical problems today. Local anesthetics play an indispensable role in pain management. The main limitation of traditional local anesthetics is the limited duration of a single injection. To address this problem, catheters are often placed or combined with other drugs in clinical practice to increase the time that local anesthetics act. However, this method does not meet the needs of clinical analgesics. Therefore, many researchers have worked to develop local anesthetic extended-release types that can be administered in a single dose. In recent years, drug extended-release systems have emerged dramatically due to their long duration and efficacy, providing more possibilities for the application of local anesthetics. This paper summarizes the types of local anesthetic drug delivery systems and their clinical applications, discusses them in the context of relevant studies on local anesthetics, and provides a summary and outlook on the development of local anesthetic extended-release agents.

Efficacy of bilateral catheter superficial parasternal intercostal plane blocks using programmed intermittent bolus for opioid-sparing postoperative analgesia in cardiac surgery with sternotomy: A randomized, double-blind, placebo-controlled trial

STUDY OBJECTIVE

This study investigated whether catheter superficial parasternal intercostal plane (SPIP) blocks, using a programmed intermittent bolus (PIB) with ropivacaine, could reduce opioid consumption while delivering enhanced analgesia for a period exceeding 48 h following cardiac surgery involving sternotomy.

DESIGN

A double-blind, prospective, randomized, placebo-controlled trial.

SETTING

University-affiliated tertiary care hospital.

PATIENTS

60 patients aged 18 or older, scheduled for cardiac surgery via sternotomy.

INTERVENTIONS

The patients were randomly assigned in a 1:1 ratio to either the ropivacaine or saline group. After surgery, patients received bilateral SPIP blocks for 48 h with 0.4% ropivacaine (20 mL per side) for induction, followed by bilateral SPIP catheters using PIB with 0.2% ropivacaine (8 mL/side, interspersed with a 2-h interval) or 0.9% normal saline following the same administration schedule. All patients were administered patient-controlled analgesia with hydromorphone.

MEASUREMENTS

The primary outcome was the cumulative morphine equivalent consumption during the initial 48 h after the surgery. Secondary outcomes included postoperative pain assessment using the Numeric Rating Scale (NRS) at rest and during coughing at designated intervals for three days post-extubation. Furthermore, recovery indicators and ropivacaine plasma levels were diligently documented.

MAIN RESULTS

Cumulative morphine consumption within 48 h in ropivacaine group decreased significantly compared to saline group (25.34 ± 31.1 mg vs 76.28 ± 77.2 mg, respectively; 95% CI, -81.9 to -20.0, P = 0.002). The ropivacaine group also reported lower NRS scores at all recorded time points (P < 0.05) and a lower incidence of nausea and vomiting than the saline group (3/29 vs 12/29, respectively; P = 0.007). Additionally, the ropivacaine group showed significant improvements in ambulation (P = 0.018), respiratory exercises (P = 0.006), and self-reported analgesia satisfaction compared to the saline group (P = 0.016).

CONCLUSIONS

Bilateral catheter SPIP blocks using PIB with ropivacaine reduced opioid consumption over 48 h, concurrently delivering superior postoperative analgesia in adult cardiac surgery with sternotomy.

Peripheral regional anaesthesia and outcomes: a narrative review of the literature from 2013 to 2023

The use of peripheral regional anaesthesia continues to increase, yet the evidence supporting its use and impact on relevant outcomes often lacks scientific rigour, especially when considering the use of specific blocks for a particular surgical indication. In this narrative review, we consider the relevant literature in a 10-yr period from 2013. We performed a literature search (MEDLINE and EMBASE) for articles reporting randomised controlled trials and other comparative trials of peripheral regional anaesthetic blocks vs systemic analgesia in adult patients undergoing surgery. We evaluated measures of effective treatment and complications. A total of 128 studies met our inclusion criteria. There remains variability in the technical conduct of blocks and the outcomes used to evaluate them. There is a considerable body of evidence to support the use of interscalene blocks for shoulder surgery. Saphenous nerve (motor-sparing) blocks provide satisfactory analgesia after knee surgery and are preferred to femoral nerve blocks which are associated with falls when patients are mobilised early as part of enhanced recovery programmes. There are additional surgical indications where the efficacy of cervical plexus, intercostal nerve, and ilioinguinal/iliohypogastric nerve blocks have been demonstrated. In the past 10 yr, there has been a consolidation of the evidence indicating benefit of peripheral nerve blocks for specific indications. There remains great scope for rigorous, multicentre, randomised controlled trials of many peripheral nerve blocks. These would benefit from an agreed set of patient-centred outcomes.

Peripheral Regional Anesthetic Techniques in Cardiac Surgery: A Systematic Review and Meta-Analysis

OBJECTIVE

The aim of this systematic review was to investigate postoperative pain outcomes and adverse events after peripheral regional anesthesia (PRA) compared to no regional anesthesia (RA), placebo, or neuraxial anesthesia in children and adults undergoing cardiac surgery.

DESIGN

A systematic review and meta-analysis with an assessment of the risk of bias (Cochrane RoB 1) and certainty of evidence (Grading of Recommendations, Assessment, Development, and Evaluation).

SETTING

Randomized controlled trials (RCTs).

PARTICIPANTS

Adults and children undergoing heart surgery.

INTERVENTIONS

Any kind of PRA compared to no RA or placebo or neuraxial anesthesia.

MEASUREMENTS AND MAIN RESULTS

In total, 33 RCTs (2,044 patients) were included-24 of these had a high risk of bias, and 28 were performed in adults. Compared to no RA, PRA may reduce pain intensity at rest 24 hours after surgery (mean difference [MD] -0.81 points, 95% CI -1.51 to -0.10; I2 = 92%; very low certainty evidence). Peripheral regional anesthesia, compared to placebo, may reduce pain intensity at rest (MD -1.36 points, 95% CI -1.59 to -1.13; I2 = 54%; very low certainty evidence) and during movement (MD -1.00 points, 95% CI -1.34 to -0.67; I² = 72%; very low certainty evidence) 24 hours after surgery. No data after pediatric cardiac surgery could be meta-analyzed due to the low number of included trials.

CONCLUSIONS

Compared to no RA or placebo, PRA may reduce pain intensity at rest and during movement. However, these results should be interpreted cautiously because the certainty of evidence is only very low.

Pain management after cardiac surgery via median sternotomy: A systematic review with procedure-specific postoperative pain management (PROSPECT) recommendations

BACKGROUND

Pain after cardiac surgery via median sternotomy can be difficult to treat, and if inadequately managed can lead to respiratory complications, prolonged hospital stays and chronic pain.

OBJECTIVES

To evaluate available literature and develop recommendations for optimal pain management after cardiac surgery via median sternotomy.

DESIGN

A systematic review using PROcedure-SPECific Pain Management (PROSPECT) methodology.

ELIGIBILITY CRITERIA

Randomised controlled trials and systematic reviews published in the English language until November 2020 assessing postoperative pain after cardiac surgery via median sternotomy using analgesic, anaesthetic or surgical interventions.

DATA SOURCES

PubMed, Embase and Cochrane Databases.

RESULTS

Of 319 eligible studies, 209 randomised controlled trials and three systematic reviews were included in the final analysis. Pre-operative, intra-operative and postoperative interventions that reduced postoperative pain included paracetamol, non-steroidal anti-inflammatory drugs (NSAIDs), intravenous magnesium, intravenous dexmedetomidine and parasternal block/infiltration.

CONCLUSIONS

The analgesic regimen for cardiac surgery via sternotomy should include paracetamol and NSAIDs, unless contraindicated, administered intra-operatively and continued postoperatively. Intra-operative magnesium and dexmedetomidine infusions may be considered as adjuncts particularly when basic analgesics are not administered. It is not clear if combining dexmedetomidine and magnesium would provide superior pain relief compared with either drug alone. Parasternal block/surgical site infiltration is also recommended. However, no basic analgesics were used in the studies assessing these interventions. Opioids should be reserved for rescue analgesia. Other interventions, including cyclo-oxygenase-2 specific inhibitors, are not recommended because there was insufficient, inconsistent or no evidence to support their use and/or due to safety concerns.

Regional anesthesia for transplantation surgery - A white paper part 1: Thoracic transplantation surgery

Transplantation surgery continues to evolve and improve through advancements in transplant technique and technology. With the increased availability of ultrasound machines as well as the continued development of enhanced recovery after surgery (ERAS) protocols, regional anesthesia has become an essential component of providing analgesia and minimizing opioid use perioperatively. Many centers currently utilize peripheral and neuraxial blocks during transplantation surgery, but these techniques are far from standardized practices. The utilization of these procedures is often dependent on transplantation centers' historical methods and perioperative cultures. To date, no formal guidelines or recommendations exist which address the use of regional anesthesia in transplantation surgery. In response, the Society for the Advancement of Transplant Anesthesia (SATA) identified experts in both transplantation surgery and regional anesthesia to review available literature concerning these topics. The goal of this task force was to provide an overview of these publications to help guide transplantation anesthesiologists in utilizing regional anesthesia. The literature search encompassed most transplantation surgeries currently performed and the multitude of associated regional anesthetic techniques. Outcomes analyzed included analgesic effectiveness of the blocks, reduction in other analgesic modalities-particularly opioid use, improvement in patient hemodynamics, as well as associated complications. The findings summarized in this systemic review support the use of regional anesthesia for postoperative pain control after transplantation surgeries. Part 1 of the manuscript focuses on regional anesthesia performed in thoracic transplantation surgeries, and part 2 in abdominal transplantations.

Practice Advisory for Preoperative and Intraoperative Pain Management of Cardiac Surgical Patients: Part 2

Pain after cardiac surgery is of moderate to severe intensity, which increases postoperative distress and health care costs, and affects functional recovery. Opioids have been central agents in treating pain after cardiac surgery for decades. The use of multimodal analgesic strategies can promote effective postoperative pain control and help mitigate opioid exposure. This Practice Advisory is part of a series developed by the Society of Cardiovascular Anesthesiologists (SCA) Quality, Safety, and Leadership (QSL) Committee's Opioid Working Group. It is a systematic review of existing literature for various interventions related to the preoperative and intraoperative pain management of cardiac surgical patients. This Practice Advisory provides recommendations for providers caring for patients undergoing cardiac surgery. This entails developing customized pain management strategies for patients, including preoperative patient evaluation, pain management, and opioid use-focused education as well as perioperative use of multimodal analgesics and regional techniques for various cardiac surgical procedures. The literature related to this field is emerging, and future studies will provide additional guidance on ways to improve clinically meaningful patient outcomes.

Comparison of regional anesthetic techniques for postoperative analgesia after adult cardiac surgery: bayesian network meta-analysis

Background

Patients usually suffer acute pain after cardiac surgery. Numerous regional anesthetic techniques have been used for those patients under general anesthesia. The most effective regional anesthetic technique was still unclear.

Methods

Five databases were searched, including PubMed, MEDLINE, Embase, ClinicalTrials.gov, and Cochrane Library. The efficiency outcomes were pain scores, cumulative morphine consumption, and the need for rescue analgesia in this Bayesian analysis. Postoperative nausea, vomiting and pruritus were safety outcomes. Functional outcomes included the time to tracheal extubation, ICU stay, hospital stay, and mortality.

Results

This meta-analysis included 65 randomized controlled trials involving 5,013 patients. Eight regional anesthetic techniques were involved, including thoracic epidural analgesia (TEA), erector spinae plane block, and transversus thoracic muscle plane block. Compared to controls (who have not received regional anesthetic techniques), TEA reduced the pain scores at 6, 12, 24 and 48 h both at rest and cough, decreased the rate of need for rescue analgesia (OR = 0.10, 95% CI: 0.016-0.55), shortened the time to tracheal extubation (MD = -181.55, 95% CI: -243.05 to -121.33) and the duration of hospital stay (MD = -0.73, 95% CI: -1.22 to -0.24). Erector spinae plane block reduced the pain score 6 h at rest and the risk of pruritus, shortened the duration of ICU stay compared to controls. Transversus thoracic muscle plane block reduced the pain scores 6 and 12 h at rest compared to controls. The cumulative morphine consumption of each technique was similar at 24, 48 h. Other outcomes were also similar among these regional anesthetic techniques.

Conclusions

TEA seems the most effective regional postoperative anesthesia for patients after cardiac surgery by reducing the pain scores and decreasing the rate of need for rescue analgesia.

Systematic Review Registration

https://www.crd.york.ac.uk/prospero/, ID: CRD42021276645.

Ultrasound Guided Parasternal Block for Perioperative Analgesia in Cardiac Surgery: A Prospective Study

Ultrasound guided parasternal block is a regional anaesthesia technique targeting the anterior branches of intercostal nerves, which supply the anterior thoracic wall. The aim of this prospective study is to assess the efficacy of parasternal block to manage postoperative analgesia and reduce opioid consumption in patients undergoing cardiac surgery throughout sternotomy. A total of 126 consecutive patients were allocated to two different groups, receiving (Parasternal group) or not (Control group) preoperative ultrasound guided bilateral parasternal block with 20 mL of 0.5% ropivacaine per side. The following data were recorded: postoperative pain expressed by a 0-10 numeric rating scale (NRS), intraoperative fentanyl consumption, postoperative morphine consumption, time to extubation and perioperative pulmonary performance at incentive spirometry. Postoperative NRS was not significantly different between Parasternal and Control groups with a median (IQR) of 2 (0-4.5) vs. 3 (0-6) upon awakening (p = 0.07); 0 (0-3) vs. 2 (0-4) at 6 h (p = 0.46); 0 (0-2) vs. 0 (0-2) at 12 h (p = 0.57). Postoperative morphine consumption was similar among groups. However, intraoperative fentanyl consumption was significantly lower in the Parasternal group [406.3 ± 81.6 mcg vs. 864.3 ± 154.4, (p < 0.001)]. Parasternal group showed shorter times to extubation [(191 ± 58 min vs. 305 ± 72 min, (p)] and better performance at incentive spirometer with a median (IQR) of 2 raised balls (1-2) vs. 1 (1-2) after awakening (p = 0.04). Ultrasound guided parasternal block provided an optimal perioperative analgesia with a significant reduction in intraoperative opioid consumption, time to extubation and a better postoperative performance at spirometry when compared to the Control group.

Sternotomy Wound Infiltration With Liposomal Versus Plain Bupivacaine for Postoperative Analgesia After Elective Cardiac Surgery

OBJECTIVES

Poor pain control after cardiac surgery can be associated with postoperative complications, longer recovery, and development of chronic pain. The authors hypothesized that adding liposomal bupivacaine (LB) to plain bupivacaine (PB) will provide better and long-lasting analgesia when used for wound infiltration in median sternotomy.

STUDY DESIGN

Prospective, randomized, and double-blinded clinical trial.

SETTING

Single institution, tertiary care university hospital.

PARTICIPANTS

Adult patients who underwent elective cardiac surgery through median sternotomy.

INTERVENTIONS

A single surgeon performed wound infiltration of LB plus PB or PB into the sternotomy wound, chest, and mediastinal tube sites.

MEASUREMENTS AND MAIN RESULTS

Patients were followed up for 72 hours for pain scores, opioid consumption, and adverse events. Sixty patients completed the study for analysis (LB group [n = 29], PB group [n = 31]). Patient characteristics, procedural variables, and pain scores measured at specific intervals from 4 hours until 72 hours postoperatively did not reveal any significant differences between the groups. Mixed-model regression showed that the trend of mean pain scores at movement in the LB group was significantly (p = 0.01) lower compared with the PB group. Opioid consumption over 72 hours was not significantly different between the 2 groups (oral morphine equivalents; median [interquartile range], 139 [73, 212] mg in LB v 105 [54, 188] mg in PB, p = 0.29). Recovery characteristics and adverse events were comparable.

CONCLUSIONS

LB added to PB for sternotomy wound infiltration during elective cardiac surgery did not significantly improve the quality of postoperative analgesia.

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.

Median sternotomy pain after cardiac surgery: To block, or not? A systematic review and meta-analysis

BACKGROUND

Inadequate pain control after median sternotomy leads to reduced mobilization, increased respiratory complications, and longer hospital stays. Typically, postoperative pain is controlled by opioid analgesics that may have several adverse effects. Parasternal intercostal block (PSB) has emerged as part of a multimodal strategy to control pain after median sternotomy. However, the effectiveness of this intervention on postoperative pain control and analgesic use has not been fully established.

METHODS AND RESULTS

We conducted a meta-analysis to assess the effect of PSB on postoperative pain and analgesic use in adult cardiac surgery patients undergoing median sternotomy. PubMed, Embase, Google Scholar, and the Cochrane database were searched with the following search strategy: ([postoperative pain] or [pain relief] OR [analgesics] or [analgesia] or [nerve block] or [regional block] or [local block] or [regional anesthesia] or [local anesthetic] or [parasternal block] and [sternotomy]) and (humans [filter]). Inclusion criteria were: patients who underwent cardiac surgery via median sternotomy, age >18 and parasternal block (continuous and single dose). Exclusion criteria were: noncardiac surgery, nonparasternal nerve blocks, and the use of NSAIDS in parasternal block. Quality assessment was performed by three independent reviewers via the Cochrane risk of bias assessment tool. Of 1165 total citations, 18 were found to be relevant. Of these 18 citations, 7 citations (N = 2223 patients) reported postoperative pain scores in an extractable format and 11 citations (N = 2155 patients) reported postoperative opioid use in an extractable format. For postoperative opioid use, morphine equivalent doses were calculated for all studies and postoperative pain scores were standardized to a 10-point visual analog scale for comparison between studies; both these were reported as total opioid use or cumulative score ranging from 24 to 72 h postoperative. All data analyses were run using a random effects model, using a restricted maximum likelihood estimator, to obtain summary standardized mean differences with 95% confidence interval (CI's). For studies which only reported median and interquatile range (IQR), the median was standard deviation was estimated by IQR/1.35. Following median sternotomy both postoperative pain (SMD [95% CI] -0.49 [-0.92 to -0.06]) and postoperative morphine equivalent use (SMD [95% CI] -1.68 [-3.11 to -0.25]) were significantly less in the PSB group.

CONCLUSION

Our meta-analysis suggests that parasternal nerve block significantly reduces postoperative pain and opioid use.

Randomized Trial of Bupivacaine Versus Liposomal Bupivacaine in Minimally Invasive Lobectomy

BACKGROUND

The objective of this single-blind randomized study is to compare local infiltration of bupivacaine or liposomal bupivacaine (LipoB) in narcotic naïve patients undergoing minimally invasive lobectomy for early stage lung cancer.

METHODS

Adult patients without previous lung surgery undergoing minimally invasive lobectomy (robotic or thoracoscopic) for early stage lung cancer were randomly assigned to bupivacaine (with epinephrine 0.25%, 1:200 000) or LipoB 1.3%. Pain level was documented using the visual analog scale and morphine equivalents for narcotic pain medications. Inhospital treatment cost and pharmacy cost were compared.

RESULTS

The study enrolled 50 patients (bupivacaine, 24; LipoB, 26). The mean age of patients was 66 years, 94% were non-Hispanic white, and 48% were male. There was no difference in baseline characteristics and comorbidities. Duration of surgery (105 vs 137 minutes, P = .152), chest tube duration (49 vs 55 hours, P = .126), and length of stay (2.45 vs 3.28 days, P = .326) were similar between treatments. Inhospital morphine equivalents were 42.7 mg vs 48 mg (P = .714), and the median pain score was 5.2 vs 4.75 (P = .602) for bupivacaine vs LipoB, respectively. There was no difference in narcotic use at 2 to 4 weeks (57.1% [12 of 21] vs 54.5% [12 of 22], P = 1.00), and at 6 months (5.9% [1 of 17] vs 9.5% [2 of 21], P = 1.00) after surgery. The overall cost ($20 252 vs $22 775, P = .225) was similar; however, pharmacy cost for LipoB was higher ($1052 vs $596, P = .0001).

CONCLUSIONS

In narcotic naïve patients undergoing minimally invasive lobectomy, short-term narcotic use, postoperative pain scores, length of stay, and long-term narcotic use were similar between bupivacaine and LipoB.

Regional anesthesia techniques for cardiac surgery: where are we?

PURPOSE OF REVIEW

Inadequate pain relief after cardiac surgery results in decreased patient experience and satisfaction, increased opioid consumption with its associated adverse consequences, and reduced efficiency metrics. To mitigate this, regional analgesic techniques are an increasingly important part of the perioperative cardiac anesthesia care plan. The purpose of this review is to compare current regional anesthesia techniques, and the relative evidence supporting their efficacy and safety in cardiac surgery.

RECENT FINDINGS

Numerous novel plane blocks have been developed in recent years, with evidence of improved pain control after cardiac surgery.

SUMMARY

The current data supports the use of a variety of different regional anesthesia techniques to reduce acute pain after cardiac surgery. However, future randomized trials are needed to quantify and compare the efficacy and safety of different regional techniques for pain control after cardiac surgery.

Use of Ultrasound-Guided Interfascial Plane Blocks in Anterior and Lateral Thoracic Wall Region as Safe Method for Patient Anesthesia and Analgesia: Review of Techniques and Approaches during COVID-19 Pandemic

Ultrasound-guided interfascial plane blocks performed on the anterior and lateral thoracic wall have become an important adjuvant method to general anesthesia and an independent method of local anesthesia and pain management. These procedures diminish the harmful effects of anesthesia on respiratory function and reduce the risk of phrenic nerve paralysis or iatrogenic pneumothorax. In postoperative pain management, interfascial plane blocks decrease the dosage of intravenous drugs, including opioids. They can also eliminate the complications associated with general anesthesia when used as the sole method of anesthesia for surgical procedures. The following procedures are classified as interfascial plane blocks of the anterior and lateral thoracic wall: pectoral nerve plane block (PECS), serratus anterior plane block (SAP), transversus thoracic muscle plane block (TTP), pectoral interfascial plane block (PIF), and intercostal nerve block (ICNB). These blocks are widely used in emergency medicine, oncologic surgery, general surgery, thoracic surgery, cardiac surgery, orthopedics, cardiology, nephrology, oncology, palliative medicine, and pain medicine. Regional blocks are effective for analgesic treatment, both as an anesthesia procedure for surgery on the anterior and lateral thoracic wall and as an analgesic therapy after trauma or other conditions that induce pain in this area. In the era of the COVID-19 pandemic, ultrasound-guided interfascial plane blocks are safe alternatives for anesthesia in patients with symptoms of respiratory distress related to SARS-CoV-2 and appear to reduce the risk of COVID-19 infection among medical personnel.

Regional analgesia techniques for effective recovery from coronary artery bypass surgeries: a retrospective study involving the experience of a single center

BACKGROUND

Pain after cardiac surgery is both multifocal and multifactorial. Sternotomy, sternal retraction, internal mammary dissection, posterior rib dislocation or fracture, potential brachial plexus injury, and mediastinal and pleural drains all contribute to pain experienced in the immediate postoperative period. Ineffective pain management can result in systemic and pulmonary complications and significant cardiac consequences.

METHODS

This study compared the effectiveness of regional anesthesia techniques for perioperative pain management in cardiac surgery patients at our clinic. The effects of different analgesic methods, in terms of contributing to recovery, were examined.

RESULTS

The records of 221 patients who had undergone coronary bypass surgery were evaluated retrospectively. The extubation rate in the operating room was 91%. No patient received balloon pump support, and 20 patients were transferred to the cardiovascular intensive care unit while intubated. Regional anesthesia was performed on two of these 20 patients, but not on the remaining 18. Examination of intraoperative and postoperative opioid consumption revealed significantly lower levels among patients receiving regional anesthesia. The most effective results among the regional anesthesia techniques applied were achieved with double injection erector spinae plane block.

CONCLUSION

Regional anesthesia techniques severely limit opioid consumption during cardiac surgery. Their importance will gradually increase in terms of rapid recovery criteria. Based on our study results, double injection of the erector spinae plane block seems to be the most effective technique in cardiac surgery. We therefore favor the use of fascial plane blocks during such procedures. Trial Numbers The study is registered with ClinicalTrials (NCT05282303). Ethics committee registration and approval were Granted under Number 2021.464.IRB1.131.

Efficacy of Liposomal Bupivacaine for Sternotomy Pain After Cardiac Surgery: A Retrospective Analysis

BACKGROUND

Multimodal analgesia is a cornerstone of postoperative pain management. Different formulations of local anesthetics are available. Data to support these treatment options are limited.

OBJECTIVE

To determine the efficacy of liposomal bupivacaine compared with bupivacaine or ropivacaine in patients undergoing sternotomy for coronary artery bypass graft (CABG) and/or valve surgery.

METHODS

Single-center, retrospective, observational study at a community teaching hospital. Patients included were 18 years of age or older undergoing CABG and/or valve surgery via median sternotomy and received either liposomal bupivacaine or an active comparator. The primary outcome was opioid utilization in morphine milligram equivalent (MME) from 0 to 72 hours.

RESULTS

A total of 376 patients were included, 223 in the liposomal bupivacaine arm and 153 in the active comparator arm. There was no difference in the MME use from 0 to 72 hours among patients in the liposomal bupivacaine group compared with the comparator group (114.2 mg [75.55] vs 107.6 mg [68.4], P = 0.38). After Bonferroni correction, there was no difference in pain scores at individual time points. At 24- and 48-hour post-op, pain scores were higher with liposomal bupivacaine at 4.4 (2.7) vs 3.5 (2.8) (P = 0.01) and 3.1 (2.9) vs 2.4 (2.6) (P = 0.02).

CONCLUSION AND RELEVANCE

Based on these findings and previous studies, liposomal bupivacaine should not be routinely used for CABG and/or valve surgery through a median sternotomy given lack of superiority. This helps inform surgical practice to the role of anesthetics as part of the multimodal analgesia regimen.

Novel Local Anesthetics in Clinical Practice: Pharmacologic Considerations and Potential Roles for the Future

The treatment of pain, both acute and chronic, has been a focus of medicine for generations. Physicians have tried to develop novel ways to effectively manage pain in surgical and post-surgical settings. One intervention demonstrating efficacy is nerve blocks. Single-injection peripheral nerve blocks (PNBs) are usually preferred over continuous PNBs, since they are not associated with longer lengths of stay. The challenge of single injection PNBs is their length of duration, which at present is a major limitation. Novel preparations of local anesthetics have also been studied, and these new preparations could allow for extended duration of action of anesthetics. An emerging preparation of bupivacaine, exparel, uses a multivesicular liposomal delivery system which releases medication in a steady, controlled manner. Another extended-release local anesthetic, HTX-011, consists of a combination of bupivacaine and low-dose meloxicam. Tetrodotoxin, a naturally occurring reversible site 1 sodium channel toxin derived from pufferfish and shellfish, has shown the potential to block conduction of isolated nerves. Neosaxitoxin is a more potent reversible site 1 sodium channel toxin also found in shellfish that can also block nerve conduction. These novel formulations show great promise in terms of the ability to prolong the duration of single injection PNBs. This field is still currently in development, and more researchers will need to be done to ensure the efficacy and safety of these novel formulations. These formulations could be the future of pain management if ongoing research continues to prove positive effects and low side effect profiles.

The Analgesic Effect of Ultrasound-guided Bilateral Pectointercostal Fascial Plane Block on Sternal Wound Pain After Open Heart Surgeries: A Randomized Controlled Study

OBJECTIVES

We aimed to evaluate the analgesic efficacy of ultrasound-guided bilateral pectointercostal fascial plane block after open heart surgeries.

METHODS

Seventy patients aged above 18 years and scheduled for on-pump coronary artery bypass grafting or valve replacement or both through median sternotomy were enrolled in this study. Patients were randomly allocated into 2 groups of 35 (block group or control group). The block group had the block performed through 20 ml of a solution of 0.25% bupivacaine plus epinephrine (5 mcg/mL), and the control group received dry needling. The primary outcome was the 24-hour cumulative morphine consumption. The secondary outcomes were time to the first analgesic request, pain score, quality of oxygenation, intensive care unit stays, and hospital stay.

RESULTS

The cumulative morphine consumption in the first 24 hours was significantly lower in the block group, with a mean difference of -3.54 (95% confidence interval=-6.55 to -0.53; P=0.015). In addition, the median estimate time to the first analgesic request was significantly longer in the block group than in the control group. Finally, during the postoperative period (4 to 24 h), mean sternal wound objective pain scores were, on average, 0.58 units higher in the block group.

CONCLUSION

pectointercostal fascial block is an effective technique in reducing morphine consumption and controlling poststernotomy pain after cardiac surgeries. Also, it may have a role in better postoperative respiratory outcomes.

Assessment of Intercostal Nerve Block Analgesia for Thoracic Surgery: A Systematic Review and Meta-analysis

IMPORTANCE

The use of intercostal nerve block (ICNB) analgesia with local anesthesia is common in thoracic surgery. However, the benefits and safety of ICNB among adult patients undergoing surgery is unknown.

OBJECTIVE

To evaluate the analgesic benefits and safety of ICNB among adults undergoing thoracic surgery.

DATA SOURCES

A systematic search was performed in Ovid MEDLINE, Ovid Embase, Scopus, and the Cochrane Library databases using terms for ICNB and thoracic surgery (including thoracic surgery, thoracoscopy, thoracotomy, nerve block, intercostal nerves). The search and results were not limited by date, with the last search conducted on July 24, 2020.

STUDY SELECTION

Selected studies were experimental or observational and included adult patients undergoing cardiothoracic surgery in which ICNB was administered with local anesthesia via single injection, continuous infusion, or a combination of both techniques in at least 1 group of patients. For comparison with ICNB, studies that examined systemic analgesia and different forms of regional analgesia (such as thoracic epidural analgesia [TEA], paravertebral block [PVB], and other techniques) were included. These criteria were applied independently by 2 authors, and discrepancies were resolved by consensus. A total of 694 records were selected for screening.

DATA EXTRACTION AND SYNTHESIS

This study followed the Preferred Reporting Items for Systematic Reviews and Meta-analyses (PRISMA) reporting guideline. Data including patient characteristics, type of surgery, intervention analgesia, comparison analgesia, and primary and secondary outcomes were extracted independently by 3 authors. Synthesis was performed using a fixed-effects model.

MAIN OUTCOMES AND MEASURES

The coprimary outcomes were postoperative pain intensity (measured as the worst static or dynamic pain using a validated 10-point scale, with 0 indicating no pain and 10 indicating severe pain) and opioid consumption (measured in morphine milligram equivalents [MMEs]) at prespecified intervals (0-6 hours, 7-24 hours, 25-48 hours, 49-72 hours, and >72 hours). Clinically relevant analgesia was defined as a 1-point or greater difference in pain intensity score at any interval. Secondary outcomes included 30-day postoperative complications and pulmonary function.

RESULTS

Of 694 records screened, 608 were excluded based on prespecified exclusion criteria. The remaining 86 full-text articles were assessed for eligibility, and 20 of those articles were excluded. All of the 66 remaining studies (5184 patients; mean [SD] age, 53.9 [10.2] years; approximately 59% men and 41% women) were included in the qualitative analysis, and 59 studies (3325 patients) that provided data for at least 1 outcome were included in the quantitative meta-analysis. Experimental studies had a high risk of bias in multiple domains, including allocation concealment, blinding of participants and personnel, and blinding of outcome assessors. Marked differences (eg, crossover studies, timing of the intervention [intraoperative vs postoperative], blinding, and type of control group) were observed in the design and implementation of studies. The use of ICNB vs systemic analgesia was associated with lower static pain (0-6 hours after surgery: mean score difference, -1.40 points [95% CI, -1.46 to -1.33 points]; 7-24 hours after surgery: mean score difference, -1.27 points [95% CI, -1.40 to -1.13 points]) and lower dynamic pain (0-6 hours after surgery: mean score difference, -1.66 points [95% CI, -1.90 to -1.41 points]; 7-24 hours after surgery: mean score difference, -1.43 points [95% CI, -1.70 to -1.17 points]). Intercostal nerve block analgesia was noninferior to TEA (mean score difference in worst dynamic panic at 7-24 hours after surgery: 0.79 points; 95% CI, 0.28-1.29 points) and marginally inferior to PVB (mean score difference in worst dynamic pain at 7-24 hours after surgery: 1.29 points; 95% CI, 1.16 to 1.41 points). The largest opioid-sparing effect of ICNB vs systemic analgesia occurred at 48 hours after surgery (mean difference, -10.97 MMEs; 95% CI, -12.92 to -9.02 MMEs). The use of ICNB was associated with higher MME values compared with TEA (eg, 48 hours after surgery: mean difference, 48.31 MMEs; 95% CI, 36.11-60.52 MMEs) and PVB (eg, 48 hours after surgery: mean difference, 3.87 MMEs; 95% CI, 2.59-5.15 MMEs).

CONCLUSIONS AND RELEVANCE

In this study, single-injection ICNB was associated with a reduction in pain during the first 24 hours after thoracic surgery and was clinically noninferior to TEA or PVB. Intercostal nerve block analgesia had opioid-sparing effects; however, TEA and PVB were associated with larger decreases in postoperative MMEs, suggesting that ICNB may be most beneficial for cases in which TEA and PVB are not indicated.

Evaluation of an Enhanced Recovery After Surgery Protocol Including Parasternal Intercostal Nerve Block in Cardiac Surgery Requiring Sternotomy

BACKGROUND

Recent guidelines for perioperative care in cardiac surgery recommend multimodal pain management to decrease opioid use. We evaluated the effect of multimodal pain management including parasternal intercostal nerve block on pain control and opioid use in patients who underwent coronary artery bypass grafting (CABG) requiring sternotomy and cardiopulmonary bypass.

STUDY DESIGN

Medical records of consecutive patients who underwent CABG from 2018 to 2019 at Huntington Hospital were retrospectively queried. Patients were divided in 2 groups based on whether an Enhanced Recovery After Surgery (ERAS) pain management protocol including parasternal intercostal nerve blocks was employed. Outcomes, including length of stay, pain scores, and opioid use, were compared.

RESULTS

There was no difference in length of stay (days) 5.43 vs. 5.38 (P = .45 and average pain score 2.23 vs. 3.27 (P = .137) for patients in the ERAS and non-ERAS groups. Maximum pain score, 7.74 to 6.15 (P = .015), and opioid use (total morphine mg equivalent), 149.64 to 32.01 (P < .01), were reduced in the ERAS group.

CONCLUSION

The ERAS multimodal pain management protocol utilizing intraoperative parasternal blocks appears to reduce pain and decrease opioid use after CABG.

Year in Review 2020: Noteworthy Literature in Cardiothoracic Anesthesiology

The year 2020 was marred by the emergence of a deadly pandemic that disrupted every aspect of life. Despite the disruption, notable research accomplishments in the practice of cardiothoracic anesthesiology occurred in 2020 with an emphasis on optimizing care, improving outcomes, and expanding what is possible for patients undergoing cardiac surgery. This year's edition of Noteworthy Literature Review will focus on specific themes in cardiac anesthesiology that include preoperative anemia, predictors of acute kidney injury following cardiac surgery, pain management modalities, anticoagulation strategies after transcatheter aortic valve replacement, mechanical circulatory support, and future directions in research.

Ultrasound-guided parasternal injection in dogs: a cadaver study

OBJECTIVES

To describe the technique of performing an ultrasound-guided distal parasternal intercostal block and to determine the distribution of two volumes of methylene blue dye solution injected in canine cadavers.

STUDY DESIGN

Prospective cadaver study.

ANIMALS

A group of seven canine cadavers weighing 12-34 kg.

METHODS

The space between the transversus thoracic and the internal intercostal muscles is a virtual cavity. Ultrasound-guided injections in the distal (parasternal) intercostal space were performed using dye solution at 0.05 mL kg^-1 in each intercostal space from the second to seventh (LV, low volume, six injections per dog) in one hemithorax, and 0.1 mL kg^-1 in the third, fifth and seventh intercostal spaces (HV, high volume, three injections in each dog) on the contralateral side. Anatomical dissection was carried out to describe dye spread characteristics and staining of intercostal nerves.

RESULTS

The ultrasonographic landmarks for injection were identified in each cadaver. In the LV group the solution was found in every intercostal space (36/36), whereas the HV injection stained six intercostal spaces in two dogs, five in two, and in two dogs the solution was found in four and three spaces, respectively, demonstrating multisegmental distribution. Intrapleural staining was observed after two injections.

CONCLUSIONS AND CLINICAL RELEVANCE

Ultrasound-guided injection of 0.05 mL kg^-1 at the distal intercostal space resulted in staining of the intercostal nerve in all dogs when performed in every space and may be an appropriate alternative to previously reported techniques. A single injection of 0.1 mL kg^-1 may anaesthetize more than one intercostal nerve, but not consistently. Clinical investigations are warranted to better characterize and to refine this locoregional technique.

The Efficacy of Liposomal Bupivacaine for Opioid and Pain Reduction: A Systematic Review of Randomized Clinical Trials

Background The opioid crisis has prompted surgeons to search for alternative postoperative methods of analgesia. Liposomal bupivacaine is a long-acting local anesthetic formulation used for pain, potentially reducing opioid use. Evaluation of liposomal bupivacaine as a viable alternative for pain management is needed. The objective was to assess the efficacy of randomized clinical trials (RCTs) of liposomal bupivacaine in postoperative pain management and opioid consumption. Material and Methods The authors extracted RCTs comparing liposomal bupivacaine versus placebo or active comparators for postoperative pain or opioid reduction from PubMED/MEDLINE, Cochrane Library, and ClinicalTrials.gov. Exclusion criteria included nonhuman studies, non-RCTs, pooled studies, and inability to access full text. The following variables were abstracted: surgical specialty, number of subjects, pain and opioid outcomes, and authors' financial conflicts of interest. Results We identified 77 published RCTs, of which 63 studies with a total of 6770 subjects met inclusion criteria. Liposomal bupivacaine did not demonstrate significant pain relief compared to placebo or active agents in 74.58% of RCTs. Of the studies evaluating narcotic use, liposomal bupivacaine did not show a reduction in opioid consumption in 85.71% of RCTs. Liposomal bupivacaine, when compared to standard bupivacaine or another active agent, yielded no reduction in opioid use in 83.33% and 100.00% of studies, respectively. Clinical trials with a financial conflict of interest relating to the manufacturer of liposomal bupivacaine were significantly more likely to show pain relief (OR: 14.31 [95% CI, 2.8, 73.10], P = 0.0001) and decreased opioid consumption (OR: 12.35 [95% CI 1.40, 109.07], P = 0.0237). Of the 265 unpublished RCTs on ClinicalTrials.gov, 47.54% were withdrawn, terminated, suspended, or completed without study results available. Conclusions The efficacy of liposomal bupivacaine for providing superior postoperative pain control relative to placebo or another active agent is not supported by a majority of RCTs. Underreporting of trial results and bias due to underlying financial relationships amongst authors are two major concerns that should be considered when evaluating the available evidence.

Pain relief following sternotomy in conventional cardiac surgery: A review of non neuraxial regional nerve blocks

Acute post-operative pain following sternotomy in cardiac surgery should be adequately managed so as to avoid adverse hemodynamic consequences and pulmonary complications. In the era of fast tracking, adequate and efficient technique of post-operative analgesia enables early extubation, mobilization and discharge from intensive care unit. Due to increasing expertise in ultrasound guided blocks there is a recent surge in trial of bilateral nerve blocks for pain relief following sternotomy. The aim of this article was to review non-neuraxial regional blocks for analgesia following sternotomy in cardiac surgery. Due to the paucity of similar studies and heterogeneity, the assessment of bias, systematic review or pooled analysis/meta-analysis was not feasible. A total of 17 articles were found to be directly related to the performance of non-neuraxial regional nerve blocks across all study designs. Due to scarcity of literature, comments cannot be made on the superiority of these blocks over each other. However, most of the reviewed techniques were found to be equally efficacious or better than conventional and established techniques.

Effectiveness of Standard Local Anesthetic Bupivacaine and Liposomal Bupivacaine for Postoperative Pain Control in Patients Undergoing Truncal Incisions: A Randomized Clinical Trial

IMPORTANCE

Liposomal bupivacaine for pain relief is purported to last 3 days compared with 8 hours with standard bupivacaine. However, its effectiveness is unknown in truncal incisions for cardiothoracic or vascular operations.

OBJECTIVE

To compare the effectiveness of single-administration standard bupivacaine vs liposomal bupivacaine in patients undergoing truncal incisions.

DESIGN, SETTING, AND PARTICIPANTS

This randomized clinical trial enrolled patients undergoing sternotomy, thoracotomy, minithoracotomy, and laparotomy from a single cardiovascular surgery department in an academic medical center between November 2012 and June 2018. The study was powered to detect a Cohen effect size of 0.35 with a power of greater than 80%. Data analysis was performed from July to December 2018.

INTERVENTION

Patients were randomized to standard bupivacaine or liposomal bupivacaine.

MAIN OUTCOMES AND MEASURES

Pain was assessed over 3 postoperative days by the Numeric Rating Scale (NRS). Adjunctive opioids were converted to morphine equivalents units (MEU). NRS scores were compared using Wilcoxon rank-sum (3-day area under the curve) and 2-way nonparametric mixed models (daily scale score) to assess time-by-group interaction. Secondary outcomes included cumulative opioid consumption.

RESULTS

A total of 280 patients were analyzed, with 140 in each group (single-administration standard bupivacaine vs liposomal bupivacaine). Mean (SD) age was 60.2 (14.4) years, and 101 of 280 patients (36%) were women. Irrespective of treatment assignment, pain decreased by a mean of approximately 1 point per day over 3 days (β = -0.87; SE = 0.11; mixed model regression P < .001). Incision type was associated with pain with patients undergoing thoracotomy (including minithoracotomy) reporting highest median (interquartile range [IQR]) pain scores on postoperative days 1 (liposomal vs standard bupivacaine, 6 [4-8] vs 5 [3-7]; P = .049, Wilcoxon rank-sum) and 2 (liposomal vs standard bupivacaine, 5 [4-7] vs 4 [2-6]; P = .003, Wilcoxon rank-sum) but not day 3 (liposomal vs standard bupivacaine, 3 [2-6] vs 3 [1-5]; P = .10, Wilcoxon rank-sum), irrespective of treatment group. Median (IQR) 3-day cumulative NRS was 12.0 (8.0-16.5) for bupivacaine and 13.5 (9.0-17.0) for liposomal bupivacaine (P = .15, Wilcoxon rank-sum) Furthermore, use of opioids was greater following liposomal bupivacaine compared with standard bupivacaine (median [IQR], 41.5 [21.3-73.8] MEU vs 33.0 [17.8-62.5] MEU; P = .03, Wilcoxon rank-sum). On multivariable analysis, no interaction by incision type was observed for mean pain scores or opioid use.

CONCLUSIONS AND RELEVANCE

In this randomized clinical trial involving truncal incisions for cardiovascular procedures, liposomal bupivacaine did not provide improved pain control and did not reduce adjunctive opioid use compared with conventional bupivacaine formulation over 3 postoperative days.

TRIAL REGISTRATION

ClinicalTrials.gov Identifier: NCT02111746.

Clinical Effectiveness of Liposomal Bupivacaine Administered by Infiltration or Peripheral Nerve Block to Treat Postoperative Pain

The authors provide a comprehensive summary of all randomized, controlled trials (n = 76) involving the clinical administration of liposomal bupivacaine (Exparel; Pacira Pharmaceuticals, USA) to control postoperative pain that are currently published. When infiltrated surgically and compared with unencapsulated bupivacaine or ropivacaine, only 11% of trials (4 of 36) reported a clinically relevant and statistically significant improvement in the primary outcome favoring liposomal bupivacaine. Ninety-two percent of trials (11 of 12) suggested a peripheral nerve block with unencapsulated bupivacaine provides superior analgesia to infiltrated liposomal bupivacaine. Results were mixed for the 16 trials comparing liposomal and unencapsulated bupivacaine, both within peripheral nerve blocks. Overall, of the trials deemed at high risk for bias, 84% (16 of 19) reported statistically significant differences for their primary outcome measure(s) compared with only 14% (4 of 28) of those with a low risk of bias. The preponderance of evidence fails to support the routine use of liposomal bupivacaine over standard local anesthetics.

Effect of Liposomal Bupivacaine on Postoperative Opioid Requirements for Total Hip Arthroplasty, Total Knee Arthroplasty, Laminectomy, Hysterectomy, and Abdominoplasty Procedures

Purpose: Opioid use postoperatively has been linked to adverse events and an increase in opioid dependency. This retrospective study evaluated the effect of using liposomal bupivacaine (LB) for postoperative pain control on total opioid consumption, pain control, serious opioid-related adverse events (ORAEs), and hospital length of stay (LOS) in total knee arthroplasty (TKA), total hip arthroplasty (THA), laminectomy, hysterectomy, and abdominoplasty procedures when compared with a control group. Methods: Patients receiving LB from August 1, 2017, to February 1, 2018, for the aforementioned procedures were included for evaluation, and patients undergoing similar procedures who did not receive LB served as the control group. The principal outcome was opioid consumption through postoperative day 5 or discharge, whichever came first, assessed by morphine milligram equivalents (MMEs). Secondary outcomes included pain scores within 72 hours postoperation, hospital LOS, and serious ORAEs. Results: A total of 323 patients were identified for inclusion in the study: TKA, n = 144; THA, n = 48; laminectomy, n = 73; hysterectomy, n = 30; and abdominoplasty, n = 28. Liposomal bupivacaine use was associated with reduced postoperative opioid consumption compared with alternative therapies with a median 71 MME (25%-75%; interquartile range [IQR] = 32.5-148.5) versus 102 MME (25%-75%; IQR = 57-165), P < .005. However, higher numeric pain scores were reported in the LB group compared with the control group for postoperative day 0 with a median of 5.5 (25%-75%; IQR = 4.5-7.4) versus 5.5 (25%-75%; IQR = 4-7) in the control group ( P < .001) and on postoperative day 1 with a median of 6 (25%-75%; IQR = 4.5-7) versus 5.5 (25%-75%; IQR = 4.3-7), P < .001. There was no difference in hospital LOS or ORAEs. Conclusion: In this retrospective analysis of pain management after TKA, THA, laminectomy, hysterectomy, and abdominoplasty procedures, patients receiving LB consumed significantly less opioid medications. However, this was not associated with clinically meaningful improvements in pain scores, hospital LOS, or serious ORAEs.

Future in regional anesthesia and pain medicine: the pharmacological view

Local anesthetics are still incompletely understood, and none of the currently available drugs are optimal. The primary target of local anesthetics is the voltage-gated sodium channel (VGSC), where they lead to a temporary interruption of nerve conduction. Unfortunately, local anesthetics are neither specific at blocking a specific VGSC isoform, nor a specific cell type. We realize now that the old classification of A and C fibers according to myelin thickness is outdated, that next to differing myelin configuration, cells differ also by their molecular biology, and that there are close to 20 different neuronal subgroups when function is concerned. The ideal local anesthetic would only block sensory impulses, or even only painful impulses. In the search for that drug, several research avenues have been followed. First, efforts have been undertaken to extend duration of local anesthetics, by additives or extended-release formulation. Second, blockade of specific pain fibers has been attempted by targeting permanently charged anesthetics specifically into nociceptors. Third, blockade of specific isoforms using antibodies, and adaptation of naturally occurring neurotoxins has shown promise. Lastly, combination of local anesthetics with other analgesics may improve their duration of action.

Future in regional anesthesia: new techniques and technological advancements

Regional anesthesia has a very interesting long history, initially preferred over general anesthesia because of safety concerns, then for a period general anesthesia became safer and was preferred. The use of innovative technologies such as ultrasound technology has made the blocks safer and successful by directly visualizing targeted nerves and the location of local anesthetics. With the wide use of ultrasound in the regional anesthesia field success rate of peripheral nerve blocks increased and novel blocks techniques developed. Moreover, new extended-release local anesthetic agents have begun to be promising time-efficient and longer duration of analgesia with a single injection. In this article, we attempt to summarize some of the novel block techniques, pharmacological agents, and new technologies in the field of regional anesthesia.

Reducing Opioid Use in Patients Undergoing Cardiac Surgery - Preoperative, Intraoperative, and Critical Care Strategies

Patients undergoing cardiothoracic surgery are exposed to opioids in the operating room and intensive care unit and after hospital discharge. Opportunities exist to reduce perioperative opioid use at all stages of care and include alternative oral and intravenous medications, novel intraoperative regional anesthetic techniques, and postoperative opioid-sparing sedative and analgesic strategies. In this review, currently used and investigational strategies to reduce the opioid burden for cardiothoracic surgical patients are explored.

Ultrasound-Guided Pecto-Intercostal Fascial Block for Postoperative Pain Management in Cardiac Surgery: A Prospective, Randomized, Placebo-Controlled Trial

OBJECTIVE

To explore the effect of pecto-intercostal fascial plane block (PIFB) on postoperative opioid requirements, pain scores, lengths of intensive care unit and hospital stays and incidence of postoperative delirium in cardiac surgical patients.

DESIGN

Single- center, prospective, randomized (1:1), quadruple- blinded, placebo-controlled trial.

SETTING

Single center, tertiary- care center.

PARTICIPANTS

The study comprised 80 adult cardiac surgical patients (age >18 y) requiring median sternotomy.

INTERVENTION

Patients were randomly assigned to receive ultrasound-guided PIFB, with either 0.25% bupivacaine or placebo, on postoperative days 0 and 1.

MEASUREMENTS AND MAIN RESULTS

Of the 80 patients randomized, the mean age was 65.78 ± 8.73 in the bupivacaine group and 65.70 ± 9.86 in the placebo group (p = 0.573). Patients receiving PIFB with 0.25% bupivacaine showed a statistically significant reduction in visual analog scale scores (4.8 ± 2.7 v 5.1 ± 2.6; p < 0.001), but the 48-hour cumulative opioid requirement computed as morphine milligram equivalents was similar (40.8 ± 22.4 mg v 49.1 ± 26.9 mg; p = 0.14). There was no difference in the incidence of postoperative delirium between the groups evaluated using the 3-minute diagnostic Confusion Assessment Method (3/40 [7.5%] v 5/40 [12.5%] placebo; p = 0.45).

CONCLUSION

Patients who received PIFB with bupivacaine showed a decline in cumulative opioid consumption postoperatively, but this difference between the groups was not statistically significant. Low incidence of complications and improvement in visual analog scale pain scores suggested that the PIFB can be performed safely in this population and warrants additional studies with a larger sample size.

Comparison of preincisional and postincisional parasternal intercostal block on postoperative pain in cardiac surgery

BACKGROUND

The optimum cardiac surgical pain management has known to maintain hemodynamic stability and, reduces respiratory and cardiovascular complications. Postoperative parasternal intercostal block has shown to reduce postoperative analgesic consumption after cardiac surgery. Therefore, this study sought to investigate the effectiveness of the preoperative ultrasound guided parasternal block in reducing postoperative pain after cardiac surgery.

METHODS

This was a randomized, prospective, interventional, single blind study comprised of 90 adult patients scheduled for cardiac surgery involving sternotomy. Preoperatively and postoperatively, 0.25% bupivacaine administered in 4 mL aliquots into the anterior (2nd-6th) intercostal spaces on each side about 2 cm lateral to the sternal edge with a total volume of 40 mL under ultrasound guidance and direct vision, respectively. Postoperative pain was rated according to visual analogue scale. Secondary outcomes included intraoperative and postoperative fentanyl consumptions, dosages of rescue medications, and time to extubation.

MAIN RESULTS

There was no significant differences in visual analogue score visual analogue score at all time points till 24 hours postoperatively. Intraoperative fentanyl requirements (microgram/kg) before cardiopulmonary bypass was significantly lower in pre-incisional group than the post-incisional group (0.16 ± 0.43 vs 0.68 ± 0.72; P = .0001). Furthermore, there were no significant difference in total fentanyl requirement (7.20 ± 2.66 vs 8.37 ± 3.13; P = .06) and tramadol requirement (0.02 ± 0.15 vs 0.07 ± 0.26; P = .28) within first 24 hours. However, time to extubation was significantly higher in the preoperative group (P = .02).

CONCLUSIONS

Preoperative and postoperative parasternal intercostal block provide comparable pain relief during the postoperative period.

Injectable Lipid-Based Depot Formulations: Where Do We Stand?

The remarkable number of new molecular entities approved per year as parenteral drugs, such as biologics and complex active pharmaceutical ingredients, calls for innovative and tunable drug delivery systems. Besides making these classes of drugs available in the body, injectable depot formulations offer the unique advantage in the parenteral world of reducing the number of required injections, thus increasing effectiveness as well as patient compliance. To date, a plethora of excipients has been proposed to formulate depot systems, and among those, lipids stand out due to their unique biocompatibility properties and safety profile. Looking at the several long-acting drug delivery systems based on lipids designed so far, a legitimate question may arise: How far away are we from an ideal depot formulation? Here, we review sustained release lipid-based platforms developed in the last 5 years, namely oil-based solutions, liposomal systems, in situ forming systems, solid particles, and implants, and we critically discuss the requirements for an ideal depot formulation with respect to the used excipients, biocompatibility, and the challenges presented by the manufacturing process. Finally, we delve into lights and shadows originating from the current setups of in vitro release assays developed with the aim of assessing the translational potential of depot injectables.

Intraoperative Anesthetic and Surgical Concerns for Robotic Thoracic Surgery

Robotic thoracic surgery continues to gain momentum and is emerging as the optimal method for minimally invasive thoracic surgery. As a rapidly advancing field, continued review of the surgical and anesthetic concerns unique to robotic thoracic operations is necessary to maintain safe and efficient practice. In this review, we discuss the intraoperative concerns as they pertain to pulmonary, esophageal, and mediastinal thoracic robotic operations.

Ultrasound-guided serratus anterior plane block combined with parasternal block in subcutaneous implantable cardioverter defibrillator implantation: Results of a pilot study

BACKGROUND

The standard approach to subcutaneous defibrillator (S-ICD) implantation often requires general anesthesia or anesthesiologist-delivered deep sedation. Ultrasound-guided serratus anterior plane block (SAPB) combined with parasternal block (PSB) has been proposed in order to provide anesthesia/analgesia and to reduce the need for sedation during S-ICD implantation. In this pilot study, we compared the double-block approach (SAPB + PSB) with the single-block approach (SAPB only) and with the standard approach involving local anesthesia and sedation.

METHODS

We prospectively enrolled 22 patients undergoing S-ICD implantation: in 10, the single-block approach was adopted; in 12, the double-block approach. As a control group, we retrospectively enrolled 14 consecutive patients who had undergone S-ICD implantation under standard local anesthesia and sedation in the previous 6 months. Intra- and postprocedural data, including patient-reported pain intensity, were collected and compared in the three study groups.

RESULTS

The double-block approach was associated with a shorter procedure duration than the single-block and standard approaches (63.3 ± 7.9 vs 70.1 ± 6.8 vs 76.9 ± 7.8 min; P < .05) and with a lower dose of local an aesthetic for infiltration (18.9 ± 1.7 vs 27.5 ± 4.6 vs 44.6 ± 4.0 cc; P < .001). Both the double- and single-block approaches were associated with lower pain intensity at the device pocket and the lateral tunneling site (P < .05). The double-block approach proved superior to the other two approaches in controlling intraoperative pain at the parasternal tunneling site (P < .05).

CONCLUSIONS

In our study, SAPB combined with PSB was superior to SAPB alone and to the standard approach in controlling intraoperative pain during S-ICD implantation. In addition, this approach resulted in shorter procedure durations.

Advances of Nano-Structured Extended-Release Local Anesthetics

Extended-release local anesthetics (LAs) have drawn increasing attention with their promising role in improving analgesia and reducing adverse events of LAs. Nano-structured carriers such as liposomes and polymersomes optimally meet the demands of/for extended-release, and have been utilized in drug delivery over decades and showed satisfactory results with extended-release. Based on mature technology of liposomes, EXPAREL, the first approved liposomal LA loaded with bupivacaine, has seen its success in an extended-release form. At the same time, polymersomes has advances over liposomes with complementary profiles, which inspires the emergence of hybrid carriers. This article summarized the recent research successes on nano-structured extended-release LAs, of which liposomal and polymeric are mainstream systems. Furthermore, with continual optimization, drug delivery systems carry properties beyond simple transportation, such as specificity and responsiveness. In the near future, we may achieve targeted delivery and controlled-release properties to satisfy various analgesic requirements.