Opioid-free anesthesia: a practical guide for teaching and implementation

Opioid-free anesthesia (OFA) represents an innovative approach that prioritizes patient safety, reduces the risks associated with opioid use, and seeks to enhance recovery. Few descriptions regarding the practical and implementation aspects exist. This review serves as a practical guide on OFA teaching and application. We briefly discuss the historical use of opioids in anesthesia, side effects and their consequences. We discuss pedagogical avenues and challenges, as well as implementation of OFA in less experienced settings. Opioid use in anesthesia originally coexisted with OFA. During the last decades, the advent of multimodal analgesia has resulted in decreased opioid dosages both before and after surgery. Recently, OFA increased in popularity, supported by meta-analyses, due to reduced nausea and vomiting, with a potential, even if limited, impact on pain. OFA, as part of rational prescribing, may contribute to a more patient-centered approach. Different strategies for OFA implementation coexist. Educational aspects, leadership, guidelines, local guidance, and training are all important. We propose a framework for OFA implementation with concrete options, including patient preparation, choice of OFA pharmacological agents (according to type of surgery and patient), and postoperative care. Whilst opioids still have an important place in pain management, they have brought harms that we cannot ignore. Evidence for using opioid-sparing and OFA techniques continues to emerge and there is a need to personalize more approaches. In this review, we provide evidence-based, relatively simple methods that can be used in implementing and delivering OFA.

How to Modulate Peripheral and Central Nervous System to Treat Acute Postoperative Pain and Prevent Pain Persistence

Chronic postoperative pain (CPSP) is a major issue after surgery, which may impact on patient's quality of life. Traditionally, CPSP is believed to rely on maladaptive hyperalgesia and risk factors have been identified that predispose to CPSP, including acute postoperative pain. Despite new models of prediction are emerging, acute pain is still a modifiable factor that can be challenged with perioperative analgesic strategies. In this review we present the issue of CPSP, focusing on molecular mechanism underlying the development of acute and chronic hyperalgesia. Also, we focus on how perioperative strategies can impact directly or indirectly (by reducing postoperative pain intensity) on the development of CPSP.

Safety of spinal anesthesia and analysis of cerebrospinal fluid in SARS-CoV-2 pregnant women undergoing cesarean section: an observational prospective study

BACKGROUND

Systemic infection has always been considered a relative contraindication to neuraxial anesthesia, despite the fact that infectious complications are relatively uncommon. Pregnancy-related physiological changes and coronavirus disease (COVID-19) neurotropic features may facilitate the virus' entry into the central nervous system. The principal aim of this study was to test the safety of spinal anesthesia in "severe acute respiratory syndrome coronavirus 2" (SARS-CoV-2)-positive pregnant women and to examine cerebrospinal fluid (CSF) characteristics.

METHODS

We conducted a prospective observational single-center study in asymptomatic or paucisymptomatic consecutive pregnant SARS-CoV-2 patients who underwent spinal anesthesia for cesarean section. Women with severe infection were excluded because they underwent general anesthesia. At the time of spinal anesthesia, we collected CSF samples, and then we performed a chemical-physical analysis to look for signs of inflammation and for SARS-CoV-2 genome.

RESULTS

We included 26 women. No spinal anesthesia complications were reported in the perioperative period and after 2 months. All CSF samples were crystal clear, and all physical-chemical values were within physiological ranges: the median concentration of CSF/plasma glucose ratio was 0.66, IQR 0.5500 (0.6000-0.7100), and the average CSF protein concentration value was 23.2 mg/dl (SD 4.87). In all samples, genomes of SARS-CoV-2 and other neurotropic viruses were not detected.

CONCLUSIONS

Spinal anesthesia was safe in SARS-CoV-2 pregnant women with mild disease; no clinical maternal complications were detected, and no CSF changes indicative of inflammatory or infectious diseases that would compromise the safety of the procedure were found.

Prolonged continuous wound infusion of local anesthetic and steroid after major abdominal surgery to reduce opioid consumption: a randomized, double-blind trial

BACKGROUND

Continuous wound infusion (CWI) is effective for post-operative pain management, but the effect of prolonged infusions and the use of steroids in the infused mixture have never been addressed. We investigate the effect of prolonged CWI with ropivacaine 0.2% (R) over seven days and methylprednisolone (Mp) 1 mg/kg infused in the wound in the first 24 hours.

METHODS

This is a randomized, double blind, phase III trial (RCT) in major abdominal surgery with laparotomy. After a 24-hours pre-peritoneal CWI of R-Mp, patients were randomized to receive either R-Mp or placebo for the next 24 hours. Then, patient-controlled CWI with only ropivacaine 0.2% or placebo (according to the randomization group) was planned between 48 hours and seven days after surgery. Morphine equivalents at seven days were analyzed, together with any catheter- or drug-related side effect and PPSP at 3 months.

RESULTS

We enrolled 120 patients (63 in the CWI group, 57 in the placebo group). Prolonged CWI did not reduce opioid consumption in the first seven postoperative days (P=0.08). CWI was associated with reduced consumption of non-opioid analgesics (P=0.03). Most of the patients continued to require bolus in the surgical wound beyond 48 hours. PPSP prevalence was not different between groups.

CONCLUSIONS

Prolonged infusion with R-Mp is safe and effective but did not reduce opioid consumption in the seven days after surgery or PPSP prevalence.

Erector spinae plane block versus fascia iliaca block after total hip arthroplasty: a randomized clinical trial comparing analgesic effectiveness and motor block

Background

Ultrasound-guided, supra-inguinal fascia iliaca block (FIB) provides effective analgesia after total hip arthroplasty (THA), but is complicated by high rates of motor block. The erector spinae plane block (ESPB) is a promising motor-sparing technique. In this study, we test the analgesic superiority of FIB over ESPB, while also comparing motor impairment.

Methods

In this randomized, observer-blinded clinical trial, patients scheduled for THA with spinal anesthesia were randomly assigned to receive either ultrasound-guided FIB or ESPB preoperatively. Primary outcome was morphine consumption at 24 hours after surgery. Secondary outcomes were: pain scores; assessment of sensory and motor block; incidence of postoperative nausea and vomiting and other complications; and development of chronic post-surgical pain.

Results

Sixty patients completed the study. There were no statistically-significant differences in morphine consumption at 24 hours (p = 0.68) or pain scores at any time point. FIB produced more reliable sensory block in the femoral nerve (p = 0.001) and lateral femoral cutaneous nerve (p = 0.018) distributions. However, quadriceps motor strength was better preserved in the ESPB group when compared to the FIB group (p = 0.002). No differences were observed for hip adduction motor strength (p = 0.253). No differences between groups were observed in terms of side effects or chronic pain incidence.

Consclusions

ESPB may represent a promising alternative to FIB for postoperative analgesia after THA. ESPB and FIB offer similar opioid-sparing benefits within the first day after surgery, but ESPB results in less quadriceps motor impairment.

Opioid-Free Anesthesia and Postoperative Outcomes in Cancer Surgery: A Systematic Review

BACKGROUND

Surgery is an essential component of the treatment of solid tumors, but the perioperative course can be complicated by different factors (including anesthesia). Opioid-free anesthesia (OFA) may mitigate adverse outcomes of opioid-based anesthesia (OBA), but major questions remain on the actual impact in terms of analgesia and the improvement of surgical outcomes. To address this issue, we present a systematic review to evaluate the efficacy of OFA compared to OBA in the specific subset of cancer patients undergoing surgery.

METHODS

following the Preferred Reporting Items for Systematic reviews and Meta-Analyses (PRISMA), we searched MEDLINE, Embase and the Cochrane CENTRAL Library to include randomized controlled trials (RCTs) on adults undergoing oncological surgery, comparing OFA and OBA up to March 2022. Additional papers were added from the reference lists of identified sources. Papers were manually reviewed by two independent authors to ascertain eligibility and subsequent inclusion in qualitative analysis.

RESULTS

only two studies were eligible according to inclusion criteria. It was not possible to perform any meta-analysis. The two studies included patients undergoing prostate and gynecologic surgery on 177 patients, with significant heterogeneity in the outcomes.

CONCLUSIONS

randomized controlled trial specifically addressed to cancer patients are lacking. A knowledge gap exists, neither confirming nor rejecting the capacity of OFA to improve early postoperative outcomes in cancer surgery. Long-term consequences on specific oncological outcomes are far from being elucidated. We expect a growing body of literature in the coming years. Further studies are required with homogeneous methodology and endpoints.

Simulation-Based Medical Education and Training Enhance Anesthesia Residents' Proficiency in Erector Spinae Plane Block

Background

Advances in regional anesthesia and pain management led to the advent of ultrasound-guided fascial plane blocks, which represent a new and promising route for the administration of local anesthetics. Both practical and theoretical knowledge of locoregional anesthesia are therefore becoming fundamental, requiring specific training programs for residents. Simulation-based medical education and training (SBET) has been recently applied to ultrasound-guided regional anesthesia (UGRA) with remarkable results. With this in mind, the anesthesia and intensive care residency program of the University of Milano-Bicocca organized a 4-h regional anesthesia training workshop with the BlockSim^® (Accurate Srl, Cesena) simulator. Our study aimed to measure the residents' improvement in terms of reduction in time required to achieve an erector spinae plane (ESP) block.

Methods

Fifty-two first-year anesthesia residents were exposed to a 4-h training workshop focused on peripheral blocks. The course included an introductory theoretical session held by a locoregional anesthetist expert, a practical training on human models and mannequins using Onvision^® (B. Braun, Milano) technologies, and two test performances on the BlockSim simulator. Residents were asked to perform two ESP blocks on the BlockSim: the first without previous practice on the simulator, the second at the end of the course. Trainees were also also asked to complete a self-assessment questionnaire.

Results

The time needed to achieve the block during the second attempt was significantly shorter (131 [83, 198] vs. 68 [27, 91] s, p < 0.001). We also observed a reduction in the number of needle insertions from 3 [2, 7] to 2 [1, 4] (p = 0.002), and an improvement aiming correctly at the ESP from 30 (58%) to 46 (88%) (p < 0.001). Forty-nine (94%) of the residents reported to have improved their regional anesthesia knowledge, 38 (73%) perceived an improvement in their technical skills and 46 (88%) of the trainees declared to be “satisfied/very satisfied” with the course.

Conclusions

A 4-h hands-on course based on SBET may enhance first-year residents' UGRA ability, decrease the number of punctures and time needed to perform the ESP block, and improve the correct aim of the fascia.

Composition of the immunoglobulin G glycome associates with the severity of COVID-19

A large variation in the severity of disease symptoms is one of the key open questions in COVID-19 pandemics. The fact that only a small subset of people infected with SARS-CoV-2 develop severe disease suggests that there have to be some predisposing factors, but biomarkers that reliably predict disease severity have not been found so far. Since overactivation of the immune system is implicated in a severe form of COVID-19 and the IgG glycosylation is known to be involved in the regulation of different immune processes, we evaluated the association of inter-individual variation in IgG N-glycome composition with the severity of COVID-19. The analysis of 166 severe and 167 mild cases from hospitals in Spain, Italy and Portugal revealed statistically significant differences in the composition of the IgG N-glycome. The most notable difference was the decrease in bisecting N-acetylglucosamine (GlcNAc) in severe patients from all three cohorts. IgG galactosylation was also lower in severe cases in all cohorts, but the difference in galactosylation was not statistically significant after correction for multiple testing.

Effects of Environmental Factors on Severity and Mortality of COVID-19

Background: Most respiratory viruses show pronounced seasonality, but for SARS-CoV-2, this still needs to be documented. Methods: We examined the disease progression of COVID-19 in 6,914 patients admitted to hospitals in Europe and China. In addition, we evaluated progress of disease symptoms in 37,187 individuals reporting symptoms into the COVID Symptom Study application. Findings: Meta-analysis of the mortality risk in seven European hospitals estimated odds ratios per 1-day increase in the admission date to be 0.981 (0.973-0.988, p < 0.001) and per increase in ambient temperature of 1°C to be 0.854 (0.773-0.944, p = 0.007). Statistically significant decreases of comparable magnitude in median hospital stay, probability of transfer to the intensive care unit, and need for mechanical ventilation were also observed in most, but not all hospitals. The analysis of individually reported symptoms of 37,187 individuals in the UK also showed the decrease in symptom duration and disease severity with time. Interpretation: Severity of COVID-19 in Europe decreased significantly between March and May and the seasonality of COVID-19 is the most likely explanation.

Opioid free anesthesia: evidence for short and long-term outcome

The introduction of synthetic opioids in clinical practice played a major role in the history of anesthesiology. For years, anesthesiologists have been thinking that opioids are needed for intraoperative anesthesia. However, we now know that opioids (especially synthetic short-acting molecules) are definitely not ideal analgesics and may even be counterproductive, increasing postoperative pain. As well, opioids have revealed important drawbacks associated to poor perioperative outcomes. As a matter of fact, efforts in postoperative pain management in the last 30 years were driven by the idea of reducing/eliminating opioids from the postoperative period. However, a modern concept of anesthesia should eliminate opioids already intra-operatively towards a balanced, opioid-free approach (opioid-free anesthesia - OFA). In OFA drugs and techniques historically proven for their efficacy are combined in rational and defined protocols. They include ketamine, alpha-2 agonists, lidocaine, magnesium, anti-inflammatory drugs and regional anesthesia. Promising results have been obtained on perioperative outcome. For sure, analgesia is not reduced with OFA, but it is effective and with less opioid-related side effects. These benefits may be of particular importance in some high-risk patients, like OSAS, obese and chronic opioid-users/abusers. OFA may also increase patient-reported outcomes; despite it is difficult to specifically rule out the effect of intraoperative opioids. Finally, few data are available on long-term outcomes (persistent pain and opioid abuse, cancer outcome). New studies and data are required to elaborate the optimal approach for each patient/surgery, but interest and publication are increasing and may open the road to the wider adoption of OFA.

Genetics and Opioids: Towards More Appropriate Prescription in Cancer Pain

Opioids are extensively used in patients with cancer pain; despite their efficacy, several patients can experience ineffective analgesia and/or side effects. Pharmacogenetics is a new approach to drug prescription based on the “personalized-medicine” concept, i.e., the ability of tailoring treatments to each individual’s genetic/genomic profile. Pharmacogenetics aims to identify specific genetic variants that influence pharmacokinetics and pharmacodynamics of drugs, better determining their effectiveness/safety profile. Opioid response is a complex scenario, but some gene variants have shown a correlation with pain sensitivity, as well as with opioid metabolism and clinical efficacy/adverse events. Although questions remain unanswered, some of these gene variants may already be used to identify specific patients’ phenotypes that are more prone to experience better clinical response (i.e., better analgesia and/or less adverse events). Once adopted, this approach to opioid prescription may improve a patient’s outcome. This review summarizes the available data on genetic variants and opioid response: we will focus on basic pharmacogenetic and its impact in the clinical scenario discussing how they may lead to more appropriate opioid prescription in cancer patients.

In vitro and in vivo quantification of chloroprocaine release from an implantable device in a piglet postoperative pain model

Background

The pharmacokinetic properties and clinical advantages of the local anesthetic chloroprocaine are well known. Here, we studied the pharmacokinetic profile of a new hydrogel device loaded with chloroprocaine to investigate the potential advantages of this new strategy for postoperative pain (POP) relief.

Materials and methods

We performed both in vitro and in vivo analyses by considering plasma samples of four piglets receiving slow-release chloroprocaine. To quantify chloroprocaine and its inactive metabolite 4-amino-2-chlorobenzoic acid (ACBA), a HPLC–tandem mass spectrometry (HPLC-MS/MS) analytical method was used. Serial blood samples were collected over 108 hours, according to the exposure time to the device.

Results

Chloroprocaine was consistently found to be below the lower limit of quantification, even though a well-defined peak was observed in every chromatogram at an unexpected retention time. Concerning ACBA, we found detectable plasma concentrations between T₀ and T_12h, with a maximum plasma concentration (C_max) observed 3 hours after the device application. In the in vitro analyses, the nanogel remained in contact with plasma at 37°C for 90 minutes, 3 hours, 1 day, and 7 days. Chloroprocaine C_max was identified 1 day following exposure and C_min after 7 days, respectively. Additionally, ACBA reached the C_max following 7 days of exposure.

Conclusion

A thorough review of the literature indicates that this is the first study analyzing both in vivo and in vitro pharmacokinetic profiles of a chloroprocaine hydrogel device and is considered as a pilot study on the feasibility of including this approach to the management of POP.

Effects of anaesthesia and analgesia on long-term outcome after total knee replacement: A prospective, observational, multicentre study

BACKGROUND

Perioperative regional anaesthesia may protect from persistent postsurgical pain (PPSP) and improve outcome after total knee arthroplasty (TKA).

OBJECTIVES

Aim of this study was to evaluate the impact of regional anaesthesia on PPSP and long-term functional outcome after TKA.

DESIGN

A web-based prospective observational registry.

SETTING

Five Italian Private and University Hospitals from 2012 to 2015.

PATIENTS

Undergoing primary unilateral TKA, aged more than 18 years, informed consent, American Society of Anesthesiologists (ASA) physical status classes 1 to 3, no previous knee surgery.

INTERVENTION(S)

Personal data (age, sex, BMI and ASA class), preoperative pain assessed by numerical rating scale (NRS) score, and risk factors for PPSP were registered preoperatively. Data on anaesthetic and analgesic techniques were collected. Postoperative pain (NRS), analgesic consumption, major complications and patient satisfaction were registered up to the time of discharge. PPSP was assessed by a blinded investigator during a phone call after 1, 3 and 6 months, together with patient satisfaction, quality of life (QOL) and walking ability.

MAIN OUTCOME MEASURES

Experience of PPSP according to the type of peri-operative analgesia.

RESULTS

Five hundred sixty-three patients completed the follow-up. At 6 months, 21.6% of patients experienced PPSP, whereas autonomy was improved only in 56.3%; QOL was worsened or unchanged in 30.7% of patients and improved in 69.3%. Patients receiving continuous regional anaesthesia (epidural or peripheral nerve block) showed a lower NRS through the whole peri-operative period up to 1 month compared with both single shot peripheral nerve block and those who did not receive any type of regional anaesthesia. No difference was found between these latter two groups. Differences in PPSP at 3 or 6 months were not significantly affected by the type of anaesthesia or postoperative analgesia. A higher NRS score at 1 month, younger age, history of anxiety or depression, pro-inflammatory status, higher BMI and a lower ASA physical status were associated with a higher incidence of PPSP and worsened QOL at 6 months.

CONCLUSION

Continuous regional anaesthesia provides analgesic benefit for up to 1 month after surgery, but did not influence PPSP at 6 months. Better pain control at 1 month was associated with reduced PPSP. Patients with higher expectations from surgery, enhanced basal inflammation and a pessimistic outlook are more prone to develop PPSP.

TRIAL REGISTRATION

Clinicaltrials.gov identifier: NCT02147730.

Update on Selective Regional Analgesia for Hip Surgery Patients

In hip surgery, regional anesthesia offers benefits in pain management and recovery. There are a wide range of regional analgesic options; none have shown to be superior. Lumbar plexus block, femoral nerve block, and fascia iliaca block are the most supported by published literature. Other techniques, such as selective obturator and/or lateral femoral cutaneous nerve blocks, represent alternatives. Newer approaches, such as quadratus lumborum block and local infiltration analgesia, require rigorous studies. To realize long-term outcome benefits, postoperative regional analgesia must be tailored to the individual patient and last longer.

Immune function after major surgical interventions: the effect of postoperative pain treatment

INTRODUCTION

Impaired immune function during the perioperative period may be associated with worse short- and long-term outcomes. Morphine is considered a major contributor to immune modulation.

PATIENTS AND METHODS

We performed a pilot study to investigate postoperative immune function by analyzing peripheral blood mononuclear cells' functionality and cytokine production in 16 patients undergoing major abdominal surgery. All patients were treated with intravenous (i.v.) patient-controlled analgesia with morphine and continuous wound infusion with ropivacaine+methylprednisolone for 24 hours. After 24 hours, patients were randomized into two groups, one continuing intrawound infusion and the other receiving only i.v. analgesia. We evaluated lymphoproliferation and cytokine production by peripheral blood mononuclear cells at the end of surgery and at 24 and 48 hours postoperatively.

RESULTS

A significant reduction in TNF-α, IL-2, IFN-γ and lymphoproliferation was observed immediately after surgery, indicating impaired cell-mediated immunity. TNF-α and IFN-γ remained suppressed up to 48 hours after surgery, while a trend to normalization was observed for IL-2 and lymphoproliferation, irrespective of the treatment group. A significant inverse correlation was present between age and morphine and between age and lymphoproliferation. No negative correlation was present between morphine and cytokine production. We did not find any differences within the two groups between 24 and 48 hours in terms of morphine consumption and immune responses.

CONCLUSION

A relevant depression of cell-mediated immunity is associated with major surgery and persists despite optimal analgesia. Even though morphine may participate in immunosuppression, we did not retrieve any dose-related effect.

Sex differences in the daily rhythmicity of morphine consumption after major abdominal surgery

OBJECTIVE

The sex of the patients has been shown to affect postoperative pain and morphine consumption; still a clear understanding able to explain the reasons behind this difference struggles to emerge. Our research aimed to investigate one specific aspect of the variability in morphine consumption between sexes. Previous studies have shown that circadian rhythm can influence opioid consumption. Furthermore, circadian rhythm is different between female and male. Our analysis investigated the presence of differences in daily rhythmicity of morphine consumption between males and females.

DESIGN

This is a secondary analysis of data collected during 2 years long multicenter clinical trial (NCT01233752).

SETTINGS

Clinical data were collected in two Italian hospitals: IRCCS Foundation Policlinico S. Matteo (Pavia) and San Gerardo Hospital (Monza).

PATIENTS

The authors recorded data about morphine consumption in 157 patients who underwent major abdominal surgery, who received morphine intravenous patient-controlled analgesia (IV-PCA) as postoperative analgesia.

INTERVENTIONS

The authors analyzed the daily periodicity of effective boluses delivered by morphine IV-PCA with Poisson multilevel models, adjusted by the time of start for each pump. An effective bolus was defined as a correctly delivered bolus of 1 mg of morphine. The authors also evaluated the interactions among the time of the day and sex, age (</≥55 y), and body mass index (BMI;</≥30 kg/m²).

MAIN OUTCOME MEASURE(S)

Differences in sex of morphine consumption rhythms over the 24 hours of the day.

RESULTS

Morphine consumption showed a statistically significant daily periodicity (p < 0.001) in our study population. Consumption was higher around 2 AM (rate 0.4 mg/min·patient) and lower around 12 PM (rate 0.05 mg/min·patient). Global consumption was not associated with the pump start time, age, or sex. The daily periodicity of morphine consumption was different between males and females (p = 0.004), with males consuming more morphine during the night.

CONCLUSIONS

Our analysis confirmed the presence of daily rhythm for morphine consumption in patients treated with IV-PCA morphine after major abdominal surgery. A difference in the daily periodicity was observed between sexes. No difference emerged in daily periodicity for the categories of age and BMI.

Sublingual sufentanil tablet system Zalviso® for postoperative analgesia after knee replacement in fast track surgery: a pilot observational study

Background

Currently many TKA protocols rely on multimodal analgesic protocols with patient-controlled analgesia systems that administer opioids through a patient controlled IV infusion pump, in addition to concomitant peripheral nerve blocks and local anesthetics. Although effective, PCA IV opioids do not provide optimal results with fast track rehabilitation protocols.

Methods

The present is a retrospective study comparing the novel sublingual sufentanil PCA system (SSTS) to our standard of care foreseeing continuous femoral nerve block (cFNB) within a multimodal analgesic in a TKA fast-track protocol. The study evaluated 95 patients on SSTS (SSTS group) and 87 on cFNB (cFNB/control group) and collected data on numeric rating scores for pain from day 1–3 after surgery (T1, T2, T3), both at rest (NRS) and during movement (mNRS), patient’s ability to walk, need for supplementary analgesia (rescue dose), occurrence of adverse effects, length of hospital stay, and usability rating for SSTS by both patients and hospital staff.

Results

NRS at rest was lower in the cFNB than in the SSTS group for all 3 days after surgery, whereas mNRS scores were lower in the SSTS group at all time points measured. Adverse effects were significantly fewer among patients of the SSTS group (6% patients) than those of the cFNB (74% patients) (p <  0.001). Rescue doses were needed by 5% of SSTS patients vs 60% of cFNB. The fewer adverse events and lower pain scores for the SSTS group were associated to a notably better ability to ambulate, with all patients (100%) of the SSTS group being able to stand and walk for 10 m from T1 on; patients in the cFNB group showed a slower recovery with only 40% being able to stand and walk on T1, 70% on T2 and 85% on T3. All patients of the SSTS group had a length of stay of 4 days (day of surgery plus 3 after) as foreseen by the fast track protocol, in comparison only 36% of cFNB. Lastly, patient and nursing staff judged SSTS easy to use.

Conclusion

Our experience suggests that SSTS is a valuable strategy for routine postoperative analgesia following TKA in the context of a multimodal analgesic approach within the fast-track setting.

Continuous wound infusion with chloroprocaine in a pig model of surgical lesion: drug absorption and effects on inflammatory response

Continuous wound infusion (CWI) may protect from inflammation, hyperalgesia and persistent pain. Current local anesthetics display suboptimal pharmacokinetic profile during CWI; chloroprocaine (CP) has ideal characteristics, but has never been tested for CWI. We performed an animal study to investigate the pharmacokinetic profile and anti-inflammatory effect of CP during CWI. A total of 14 piglets received an infusion catheter after pararectal laparotomy and were randomly allocated to one of three groups: 5 mL/h infusion of saline (group A), CP 1.5% (group B) and CP 0.5% (group C). Blood sampling was performed to assess absorption and systemic inflammation at 0, 3, 6, 12, 24, 48, 72, 96, 102 and 108 hours. The wound and contralateral healthy abdominal wall were sampled for histological analyses. Absorption of CP from the site of infusion, evaluated as the plasmatic concentrations of CP and its metabolite, 4-amino-2-chlorobenzoic acid (CABA), showed a peak during the first 6 hours, but both CP and its metabolite rapidly disappeared after stopping CP infusion. Local inflammation was reduced in groups B and C (CP-treated p < 0.001), in a CP dose-dependent fashion. While CP inhibited in a dose-dependent manner pig mononuclear cells (MNCs) in vitro proliferation to a polyclonal activator, no effect on systemic cytokines’ concentrations or on ex vivo monocytes’ responsiveness was observed, suggesting the lack of systemic effects, in line with the very short half-life of CP in plasma. CP showed a very good profile for use in CWI, with dose-dependent local anti-inflammatory effects, limited absorption and rapid clearance from the bloodstream upon discontinuation. No cytotoxicity or side effects were observed. CP, therefore, may represent an optimal choice for clinical CWI, adaptable to each patient’s need, and protective on wound inflammatory response (and hyperalgesia) after surgery.

Continuous regional anesthesia: a review of perioperative outcome benefits

Routine use of regional anesthesia for patients having surgery is supported by general safety and proven effectiveness as a targeted modality in the prevention and treatment of acute pain. Recently, perioperative physicians have become much more interested in improving long-term outcomes after surgery rather than focusing on the well-established short-term benefits of regional anesthesia. This interest has raised important questions regarding the potential influence of regional anesthesia on morbidity and mortality, persistent pain and cancer prognosis. Tissue injury is responsible for the inflammatory reaction and physiologic stress response observed during the perioperative period and can influence a patient's recovery trajectory. Regional anesthesia can modulate the inflammatory response through the direct anti-inflammatory effect of local anesthetics, blocking neural afferents, and blunting sympathetic activation. Moreover, continuous techniques (e.g., epidural and perineural catheters) that provide longer duration and titratable pain relief in the perioperative period may be protective against the development of persistent post-surgical pain by providing effective acute pain management and decreasing exposure to opioids. To maximize the potential for long-term outcome benefits to surgical patients, continuous regional anesthesia techniques are preferred over single injection techniques. Although the data are not yet definitive, some studies have demonstrated better functional recovery after joint replacement and lower rates of cancer recurrence in patients treated with continuous regional anesthesia. Future research studies in regional anesthesia will have to focus on these long-term patient-centered outcomes and may need to incorporate novel study designs and analyses of big data.

Saving from unnecessary pancreaticoduodenectomy. Brunner's gland hamartoma: Case report on a rare duodenal lesion and exhaustive literature review

INTRODUCTION

Brunner's gland hamartoma (BGH) is an infrequently encountered, benign, polypoid proliferation of Brunner's glands. Usually these lesions are asymptomatic, just only occasionally presenting with duodenal obstruction or bleeding signs and mimicking a tumoral lesion.

CASE PRESENTATION

A 72-year-old male, referred for recurrent vomiting and epigastralgia, was investigated and all preoperative findings were suggestive of a tumour of the duodenum. During the scheduled pancreaticoduodenectomy a mass, resultant to a polyp, was palpatory felt inside the duodenum and then successfully and completely resected through a duodenotomy avoiding surgical overtreatment and connected postoperative morbidities. Histological analysis showed hyperplasia of Brunner's glands correspondent to a Brunner's gland hamartoma. BGH was undiagnosed before surgery, due to its particular sub-mucosal growth simulating an expanding process starting from the duodenum, and secondly due to unsuccessful biopsies performed during endoscopic procedure.

CONCLUSION

BGH is a rare lesion featuring, when symptomatic, obstructive or bleeding symptoms. Surgical treatment represents the gold standard approach in case of lesions that are technically impossible to remove endoscopically or in case of an undiagnosed lesion. Herein, we report a case of a patient presenting with a duodenal lesion mimicking, in all preoperative findings, a tumour of the duodenum. Duodenotomy and resection of the BGH provided a definitive cure avoiding surgical overtreatment. An intraoperative deep analysis of all surgical cases still remain crucial for a right therapeutic choice even in a new era for surgical technology. For similar intraoperative findings we recommend this technique.

Opioid less perioperative care

Opioids are the most frequently administered analgesics in the perioperative period. The analgesic potency of opioids is without question. While the opioid- free or opioid-less perioperative care concept is not a reality in most surgical centers of the United States and other developed countries, there is a significant number of healthcare problems (i.e. adverse events, opioid-induced hyperalgesia and opioid diversion) related to the indiscriminate use of opioids that warrants the implementation of multimodal analgesia strategies. Although it has been suggested an association between the use of opioids and cancer progression, there is a need of well-designed studies to confirm that association.

Surgical spacer placement prior carbon ion radiotherapy (CIRT): an effective feasible strategy to improve the treatment for sacral chordoma

Background

Sacral chordoma (SC) is a neoplasm arising from residual notochordal cells degeneration. SC is difficult to manage mainly because of anatomic location and tendency to extensive spread. Carbon ion radiotherapy (CIRT) is highly precise to selectively deliver high biological effective dose to the tumor target sparing the anatomical structure on its path even if when SC is contiguous to the intestine, and a surgical spacer might be an advantageous tool to create a distance around the target volume allowing radical curative dose delivery with a safe dose gradient to the surrounding organs. This paper describes a double approach—open and hand-assisted laparoscopic—for a silicon spacer placement in patients affected by sacral chordoma undergoing carbon ion radiotherapy.

Methods

Six consecutive patients have been enrolled for surgical spacer placement—open (three) or hand-assisted (three)—prior carbon ion radiotherapy treatment in order to increase efficacy of carbon ion radiotherapy minimizing its side effects.

Results

Results showed that silicon spacer placement for SC treatment is feasible both via laparoscopic and laparotomic approach.

Conclusions

Its use might improve CIRT safety and thus efficacy for SC treatment.

Changes in total plasma and serum N-glycome composition and patient-controlled analgesia after major abdominal surgery

Systemic inflammation participates to the complex healing process occurring after major surgery, thus directly affecting the surgical outcome and patient recovery. Total plasma N-glycome might be an indicator of inflammation after major surgery, as well as an anti-inflammatory therapy response marker, since protein glycosylation plays an essential role in the inflammatory cascade. Therefore, we assessed the effects of surgery on the total plasma N-glycome and the association with self-administration of postoperative morphine in two cohorts of patients that underwent major abdominal surgery. We found that plasma N-glycome undergoes significant changes one day after surgery and intensifies one day later, thus indicating a systemic physiological response. In particular, we observed the increase of bisialylated biantennary glycan, A2G2S[3,6]2, 12 hours after surgery, which progressively increased until 48 postoperative hours. Most changes occurred 24 hours after surgery with the decrease of most core-fucosylated biantennary structures, as well as the increase in sialylated tetraantennary and FA3G3S[3,3,3]3 structures. Moreover, we observed a progressive increase of sialylated triantennary and tetraantennary structures two days after surgery, with a concomitant decrease of the structures containing bisecting N-acetylglucosamine along with bi- and trisialylated triantennary glycans. We did not find any statistically significant association between morphine consumption and plasma N-glycome.

Italian Registry of Complications associated with Regional Anesthesia (RICALOR). An incidence analysis from a prospective clinical survey

BACKGROUND

Regional anesthesia (RA) is associated with many advantages, but side effects also occur. Several registries were developed to investigate such complications in many countries, which produced conflicting results. In consideration of the ongoing evolution and improvements in RA, and its widespread diffusion in Italy in the last decade (with increasing experience by anesthesiologists), a reappraisal of the incidence and the characteristics of major complications are useful to improve patient's safety.

METHODS

A web-based prospective registry was developed in Italy with: 1) quarterly report of total anesthetic acts and RA procedures performed; and 2) voluntary registration of complications on dedicated forms. We evaluated incidence of complications, describing their characteristics and outcomes.

RESULTS

Participants (N.=17 hospitals) registered 117,182 procedures, including 63,692 with RA (54.3%, both as primary anesthetic technique and for postoperative analgesia). A total of 34,147 neuraxial blocks (4954 epidurals/CSE, 29,193 subarachnoid blocks) and 29,545 peripheral (single shot and continuous) blocks were registered. Total incidence of complication was 4.6/10.000; incidence was 4.1/10,000 for central blocks and 5.1/10,000 for peripheral blocks, long-term neurologic deficit (at 6 months) was observed after an epidural abscess, while other complications did not lead to any long-term adverse outcomes. No hemorrhagic events or other infections have occurred. Incidence of major complications was 0.07/1000, while minor complications presented in 0.38/1000 cases.

CONCLUSIONS

We confirmed RA as generally safe, but monitoring and diagnosis, together with further research efforts, are needed to improve patients' care and clarify potential risk factors.

Human Genetic Variability Contributes to Postoperative Morphine Consumption

High interindividual variability in postoperative opioid consumption is related to genetic and environmental factors. We tested the association between morphine consumption, postoperative pain, and single nucleotide polymorphisms (SNPs) within opioid receptor μ 1 (OPRM1), catechol-O-methyltransferase (COMT), uridine diphosphate glucose-glucuronosyltransferase-2B7, and estrogen receptor (ESR1) gene loci to elucidate genetic prediction of opioid consumption. We analyzed 20 SNPs in 201 unrelated Caucasian patients who underwent abdominal surgery and who were receiving postoperative patient-controlled analgesia-administered morphine. Morphine consumption and pain intensity were dependent variables; age and sex were covariates. A haplotype of 7 SNPs in OPRM1 showed significant additive effects on opioid consumption (P = .007); a linear regression model including age and 9 SNPs in ESR1, OPRM1, and COMT explained the highest proportion of variance of morphine consumption (10.7%; P = .001). The minimal model including 3 SNPs in ESR1, OPRM1, and COMT explained 5% of variance (P = .007). We found a significant interaction between rs4680 in COMT and rs4986936 in ESR1 (P = .007) on opioid consumption. SNPs rs677830 and rs540825 of OPRM1 and rs9340799 of ESR1 were nominally associated with pain Numeric Rating Scale scores. Combinations of genetic variants within OPRM1, COMT, and ESR1 better explain variability in morphine consumption than single genetic variants. Our results contribute to the development of genetic markers and statistical models for future diagnostic tools for opioid consumption/efficacy.

PERSPECTIVE

This article presents the efforts dedicated to detect correlations between the genetic polymorphisms and the clinical morphine effect self-administered by patients using a patient-controlled analgesia pump after major surgery. The clinical effect is expressed in terms of morphine consumption and pain scores. REGISTERED ON CLINICALTRIALS.GOV: NCT01233752.

Effect of postoperative analgesia on acute and persistent postherniotomy pain: a randomized study

STUDY OBJECTIVE

The study objective is to identify differences in postoperative pain management according to different analgesic treatments, targeting 2 main pathways involved in pain perception.

DESIGN

The design is a randomized, parallel groups, open-label study.

SETTING

The setting is in an operating room, postoperative recovery area, and surgical ward.

PATIENTS

There are 200 patients undergoing open inguinal hernia repair (IHR) with tension-free technique (mesh repair).

INTERVENTIONS

The intervention is a randomization to receive ketorolac (group K) or tramadol (group T) for 3 days after surgery.

MEASUREMENTS

The measurements are differences in analgesic efficacy (numeric rating scale [NRS]) in the postoperative (up to 5 days) period, chronic pain incidence (1 and 3 months), side effects, and complications.

MAIN RESULTS

We found no differences in analgesic efficacy (NRS value ≥4 in the first 96 hours: 26% in group K vs 32% in group T, P = .43); the proportion of patients with NRS ≥4 was similar in both groups, and the time trajectories were not significantly different (P for interaction = .24). Side effects were higher (12% vs 6%) in the tramadol group, although not significantly (P = .14), with a case of bleeding in the ketorolac group and higher incidence of constipation in tramadol group. One patient in each group developed chronic pain.

CONCLUSIONS

Ketorolac or weak opioids are equally effective on acute pain and on persistent postsurgical pain development after IHR, and drug choice should be based on their potential side effects and patient's comorbidities. Further studies are needed to standardize the most rational approach to prevent persistent postsurgical pain after IHR.

Continuous wound infusion of local anesthetic and steroid after major abdominal surgery: study protocol for a randomized controlled trial

Background

Inflammatory response is one of the key components of pain perception. Continuous infusion (CWI) of local anesthetics has been shown to be effective in controlling pain and reducing postoperative morphine consumption, but the effect of adding a potent anti-inflammatory drug (such as a steroid) has never been addressed. In our study, we want to investigate the effect of CWI with local anesthetic + methylprednisolone on acute and persistent pain, correlating clinical data with biomarkers of inflammation and genetic background.

Methods/Design

After approval by their institutional review board, three hospitals will enroll 120 patients undergoing major abdominal surgery in a randomized, double-blind, phase III study. After a 24-h CWI of ropivacaine 0.2 % + methylprednisolone 1 mg/kg, patients will be randomly assigned to receive either ropivacaine + steroid or placebo for the next 24 h. Then, patient-controlled CWI with only ropivacaine 0.2 % or placebo (according to the group of randomization) is planned after 48 h up to 7 days (bolus 10 ml, lock-out 1 h, maximum dose of 40 ml in 4 h). Morphine equivalent consumption up to 7 days will be analyzed, together with any catheter- or drug-related side effect. Persistent post-surgical pain (PPSP) incidence will also be investigated. Our primary endpoint is analgesic consumption in the first 7 days after surgery; we will evaluate, as secondary endpoints, any catheter- or drug-related side effect, genotype/phenotype correlations between some polymorphisms and postoperative outcome in terms of morphine consumption, development of the inflammatory response, and incidence of PPSP. Finally, we will collect, in a subgroup of patients, wound exudate samples by micro-dialysis, blood samples, and urine samples up to 72 h to investigate local and systemic inflammation and oxidative stress.

Discussion

This is a phase III trial to evaluate the safety and efficacy of wound infusion with steroid and local anesthetic. The study is aimed also to evaluate how long this infusion has to be maintained in order to maximize effectiveness. Our data are intended to quantify the amount of ropivacaine and methylprednisolone needed by patients undergoing major abdominal surgery, to be stored in a new nanotechnology device for sustained pain treatment after surgery. We also aim to clarify the roles of inflammatory response, oxidative stress, and genetic background on postoperative and persistent pain after major abdominal surgery.

Trial registration

The trial was registered on ClinicalTrials.gov (NCT02002663) on 24 Oct. 2013.

Best practice in the administration of analgesia in postoncological surgery

The rationale for using multimodal analgesia after any major surgery is achievement of adequate analgesia while avoiding the unwanted effects of large doses of any analgesic, in particular opioids. There are two reasons why we can hypothesize that multimodal analgesia might have a significant impact on cancer-related outcomes in the context of oncological orthopedic surgery. First, because multimodal analgesia is a key component of enhanced-recovery pathways and can accelerate return to intended oncological therapy. And second, because some of the analgesic used in multimodal analgesia (i.e., COX inhibitors, local analgesics and dexamethasone) can induce apoptosis in cancer cells and/or diminish the inflammatory response during surgery which itself can facilitate tumor growth.

Postoperative Analgesia after Laparoscopic Ovarian Cyst Resection: Double-blind Multicenter Randomized Control Trial Comparing Intraperitoneal Nebulization and Peritoneal Instillation of Ropivacaine

STUDY OBJECTIVE

To compare the effects of local anesthetic intraperitoneal nebulization with intraperitoneal instillation during laparoscopic ovarian cystectomy on postoperative morphine consumption and pain.

DESIGN

Multicenter, randomized, case-control trial.

DESIGN CLASSIFICATION

Canadian Task Force Classification I.

SETTING

University hospitals in Italy.

PATIENTS

One hundred forty patients scheduled for laparoscopic ovarian cystectomy.

INTERVENTIONS

Patients were randomized to receive either nebulization of ropivacaine 150 mg before surgery or instillation of ropivacaine 150 mg before surgery. Nebulization was performed using the Aeroneb Pro device (Aerogen, Galway, Ireland).

MEASUREMENTS AND MAIN RESULTS

One hundred forty patients were enrolled, and 123 completed the study. There was no difference between the 2 groups in average morphine consumption (7.3 ± 7.5 mg in the nebulization group vs 9.2 ± 7.2 mg in the instillation group; p = .17). Eighty-two percent of patients in the nebulization group required morphine compared with 96% in the instillation group (p < .05). Patients receiving nebulization had a lower dynamic Numeric Ranking Scale compared with those in the instillation group in the postanesthesia care unit postanesthesia care unit and 4 hours after surgery (p < .05). Ten patients (15%) in the nebulization group experienced shivering in the postanesthesia care unit compared with 2 patients (4%) in the instillation group (p = .035).

CONCLUSION

Nebulization of ropivacaine prevents the use of morphine in a significant proportion of patients, reduced postoperative pain during the first hours after surgery, and was associated with a higher incidence of postoperative shivering when compared with instillation.