Local anaesthetics and regional anaesthesia versus conventional analgesia for preventing persistent postoperative pain in adults and children

Integrating mechanistic-based and classification-based concepts into perioperative pain management: an educational guide for acute pain physicians

Chronic pain begins with acute pain. Physicians tend to classify pain by duration (acute vs chronic) and mechanism (nociceptive, neuropathic and nociplastic). Although this taxonomy may facilitate diagnosis and documentation, such categories are to some degree arbitrary constructs, with significant overlap in terms of mechanisms and treatments. In clinical practice, there are myriad different definitions for chronic pain and a substantial portion of chronic pain involves mixed phenotypes. Classification of pain based on acuity and mechanisms informs management at all levels and constitutes a critical part of guidelines and treatment for chronic pain care. Yet specialty care is often siloed, with advances in understanding lagging years behind in some areas in which these developments should be at the forefront of clinical practice. For example, in perioperative pain management, enhanced recovery protocols are not standardized and tend to drive treatment without consideration of mechanisms, which in many cases may be incongruent with personalized medicine and mechanism-based treatment. In this educational document, we discuss mechanisms and classification of pain as it pertains to commonly performed surgical procedures. Our goal is to provide a clinical reference for the acute pain physician to facilitate pain management decision-making (both diagnosis and therapy) in the perioperative period.

Local Wound Infiltration for Thyroidectomized Patients in the Era of Multimodal Analgesia

The first few hours following thyroidectomy are the most crucial for pain management. Adequate postoperative pain control, reduction in opioid abuse and the possibility of implementing one-day operations are the considered parameters when developing the postoperative analgesic strategy. A study of the available literature was conducted, exploring the efficacy of (open) thyroidectomy wound infiltration. Seventeen full-text RCTs were extracted. Local anesthetics and non-steroidal anti-inflammatory drugs were infiltrated. Emphasis was given to postoperative pain scores and requirements for rescue analgesia with opioids. Most authors agree that local wound infiltration for thyroidectomized patients is effective in the management of postoperative pain parameters. In the era of multimodal analgesia, thyroidectomy wound infiltration could represent an essential adjunct contributing to lower VAS scores and reduced opioid requirements.

The Acute Perioperative Pain Service: Impact, Organization, and Future Directions

PURPOSE OF REVIEW

The Acute Perioperative Pain Service has been established as a relatively new but important concept and service in clinical patient care. Many surgical institutions have dedicated inpatient acute pain services with variable compositions. This review aims to investigate the purpose, clinical and economic implications, and future direction of the Acute Perioperative Pain Service (APPS).

RECENT FINDINGS

There is growing evidence of the multiple benefits of a dedicated APPS, especially pertaining to patients at higher risk of poorly controlled postoperative pain. Healthcare providers furthermore realize the importance of the perioperative pain management continuity of care, consisting of preoperative pain evaluations and post-discharge follow-up in an outpatient pain management setting, in coordination with the primary teams. The Transitional Pain Service (TPS) has emerged as the next step in this evolution and has been successfully implemented at various medical centers. With the growing number of surgical procedures and the increasing complexity of the patient population, effective management of acute postoperative pain continues to be challenging, despite ongoing advances in clinical care, analgesic modalities, and research. The APPS is becoming the clinical standard of care for managing postoperative pain, and its role continues to expand worldwide.

The mechanisms and management of persistent postsurgical pain

An estimated 10%-50% of patients undergoing a surgical intervention will develop persistent postsurgical pain (PPP) lasting more than 3 months despite adequate acute pain management and the availability of minimally invasive procedures. The link between early and late pain outcomes for surgical procedures remains unclear-some patients improve while others develop persistent pain. The elective nature of a surgical procedure offers a unique opportunity for prophylactic or early intervention to prevent the development of PPP and improve our understanding of its associated risk factors, such as pre-operative anxiety and the duration of severe acute postoperative pain. Current perioperative pain management strategies often include opioids, but long-term consumption can lead to tolerance, addiction, opioid-induced hyperalgesia, and death. Pre-clinical models provide the opportunity to dissect mechanisms underpinning the transition from acute to chronic, or persistent, postsurgical pain. This review highlights putative mechanisms of PPP, including sensitisation of peripheral sensory neurons, neuroplasticity in the central nervous system and nociceptive signalling along the neuro-immune axis.

Identifying risk factors for chronic postsurgical pain and preventive measures: a comprehensive update

INTRODUCTION

Chronic postsurgical pain (CPSP) is a prevalent condition that can diminish health-related quality of life, cause functional deficits, and lead to patient distress. Rates of CPSP are higher for certain types of surgeries than others (thoracic, breast, or lower extremity amputations) but can occur after even uncomplicated minimally invasive procedures. CPSP has multiple mechanisms, but always starts as acute postsurgical pain, which involves inflammatory processes and may encompass direct or indirect neural injury. Risk factors for CPSP are largely known but many, such as female sex, younger age, or type of surgery, are not modifiable. The best strategy against CPSP is to quickly and effectively treat acute postoperative pain using a multimodal analgesic regimen that is safe, effective, and spares opioids.

AREAS COVERED

This is a narrative review of the literature.

EXPERT OPINION

Every surgical patient is at some risk for CPSP. Control of acute postoperative pain appears to be the most effective approach, but principles of good opioid stewardship should apply. The role of regional anesthetics as analgesics is gaining interest and may be appropriate for certain patients. Finally, patients should be better informed about their relative risk for CPSP.

Perioperative Administration of Pregabalin and Esketamine to Prevent Chronic Pain After Breast Cancer Surgery: A Randomized Controlled Trial

Background

Perioperative multimodal analgesia can prevent chronic pain after breast cancer surgery. This study aimed to investigate the efficacy of combined perioperative oral pregabalin and postoperative esketamine in preventing chronic pain after breast cancer surgery.

Methods

Ninety patients undergoing elective breast cancer surgery were randomized into the combined pregabalin and esketamine group (EP group) and the general anesthesia alone group (Control group). The EP group received 150 mg of oral pregabalin 1 h before surgery and twice daily for seven days postoperatively, and a patient-controlled analgesia pump after surgery that delivered 100 μg sufentanil + 1.25 mg/kg esketamine + 4 mg tropisetron in 100 mL saline solution intravenously. The Control group received placebo capsules before and after the surgery and routine postoperative analgesia (100 μg sufentanil + 4 mg tropisetron in 100 mL saline solution). The primary outcome was the incidence of chronic pain three and six months after surgery. Secondary outcomes included acute postoperative pain, postoperative opioid consumption, and incidence of adverse events.

Results

The incidence of chronic pain in the EP group was significantly lower than in the Control group three (14.3% vs 46.3%, P = 0.005) and six (7.1% vs 31.7%, P = 0.009) months postoperatively. The rest numerical rating scale (NRS) pain scores 1-3 days postoperatively and coughing NRS pain scores 1-7 days postoperatively in the EP group were significantly lower than in the Control group (all P ˂ 0.05). The cumulative sufentanil consumption in the EP group during postoperative 0-12, 12-24, and 24-48, 0-24, and 0-48 hours were significantly lower than in the Control group (all P ˂ 0.05).

Conclusion

Combined perioperative oral pregabalin and postoperative esketamine effectively prevented chronic pain after breast cancer surgery, improved acute postoperative pain, and reduced postoperative opioid consumption.

Paravertebral Blocks in Tissue Expander Breast Reconstruction: Propensity-Matched Analysis of Opioid Consumption and Patient Outcomes

BACKGROUND

The paravertebral block (PVB) is an adjunctive perioperative pain control method for patients undergoing breast reconstruction that may improve perioperative pain control and reduce narcotic use. This study determined the efficacy of preoperative PVBs for perioperative pain management in patients undergoing tissue expander breast reconstruction.

METHODS

A retrospective review was performed of patients who underwent tissue expander breast reconstruction from December of 2017 to September of 2019. Two patients with PVBs were matched using propensity scoring to one no-block patient. Perioperative analgesic use, pain severity scores on days 2 to 10 after discharge, and BREAST-Q Physical Well-Being scores before surgery and at 2 weeks, 6 weeks, and 3 months after surgery were compared between the two groups.

RESULTS

The propensity-matched cohort consisted of 471 patients (314 PVB and 157 no block). The PVB group used significantly fewer morphine milligram equivalents than the no-block group (53.7 versus 69.8; P < 0.001). Average daily postoperative pain severity scores were comparable, with a maximum difference of 0.3 points on a 0-point to 4-point scale. BREAST-Q Physical Well-Being scores were significantly higher for the PVB group than the no-block group at 6 weeks after surgery (60.6 versus 51.0; P = 0.015) but did not differ significantly at 2 weeks or 3 months after surgery.

CONCLUSIONS

PVBs may help reduce perioperative opioid requirements but did not reduce pain scores after discharge when used as part of an expander-based reconstruction perioperative pain management protocol. Continued research should examine additional or alternative regional block procedures as well as financial cost and potential long-term impact of PVBs.

CLINICAL QUESTION/LEVEL OF EVIDENCE

Therapeutic, III.

One year follow-up on a randomized study investigating serratus anterior muscle and pectoral nerves type I block to reduced neuropathic pain descriptors after mastectomy

Breast cancer is the second most common diagnosed type of cancer in women. Chronic neuropathic pain after mastectomy occurs frequently and is a serious health problem. In our previous single-center, prospective, randomized controlled clinical study, we demonstrated that the combination of serratus anterior plane block (SAM) and pectoral nerve block type I (PECS I) with general anesthesia reduced acute postoperative pain. The present report describes a prospective follow-up study of this published study to investigate the development of chronic neuropathic pain 12 months after mastectomy by comparing the use of general anesthesia alone and general anesthesia with SAM + PECS I. Additionally, the use of analgesic medication, quality of life, depressive symptoms, and possible correlations between plasma levels of interleukin (IL)-1 beta, IL-6, and IL-10 collected before and 24 h after surgery as predictors of pain and depression were evaluated. The results showed that the use of SAM + PECS I with general anesthesia reduced numbness, hypoesthesia to touch, the incidence of patients with chronic pain in other body regions and depressive symptoms, however, did not significantly reduce the incidence of chronic neuropathic pain after mastectomy. Additionally, there was no difference in the consumption of analgesic medication and quality of life. Furthermore, no correlation was observed between IL-1 beta, IL-6, and IL-10 levels and pain and depression. The combination of general anesthesia with SAM + PECS I reduced the occurrence of specific neuropathic pain descriptors and depressive symptoms. These results could promote the use of SAM + PECS I blocks for the prevention of specific neuropathic pain symptoms after mastectomy.Registration of clinical trial: The Research Ethics Board of the Hospital Sirio-Libanes/Brazil approved the study (CAAE 48721715.0.0000.5461). This study is registered at Registro Brasileiro de Ensaios Clinicos (ReBEC), and ClinicalTrials.gov, Identifier: NCT02647385.

Editorial for the Special Issue: "Advances in Postoperative Pain Management and Chronic Postoperative Pain"

Acute and chronic pain are two completely distinct universes [...].

Erector Spinae Plane Block Decreases Chronic Postoperative Pain Severity in Patients Undergoing Coronary Artery Bypass Grafting

Up to 56% of patients develop chronic postsurgical pain (CPSP) after coronary artery bypass grafting (CABG). CPSP can affect patients’ moods and decrease daily activities. The primary aim of this study was to investigate CPSP severity in patients following off-pump (OP) CABG using the Neuropathic Pain Symptom Inventory (NPSI). This was a prospective cohort study conducted in a cardiac surgery department of a teaching hospital. Patients undergoing OP-CABG were enrolled in an erector spinae plane block (ESPB) group (n = 27) or a control (CON) group (n = 24). Before the induction of general anesthesia, ESPB was performed on both sides under ultrasound guidance using 0.375% ropivacaine. The secondary outcomes included cumulative oxycodone consumption, acute pain intensity, mechanical ventilation time, hospital length of stay, and postoperative complications. CPSP intensity was lower in the ESPB group than in the CON group 1, 3, and 6 months post-surgery (p < 0.001). Significant between-group differences were also observed in other outcomes, including postoperative pain severity, opioid consumption, mechanical ventilation time, and hospital length of stay, in favor of the ESPB group. Preemptive ESPB appears to decrease the risk of CPSP development in patients undergoing OP-CABG. Reduced acute pain severity and shorter mechanical ventilation times and hospital stays should improve patients’ satisfaction and reduce perioperative complications.

The Role of Regional Anesthesia in the Development of Chronic Pain: a Review of Literature

Purpose of Review

The acute management of pain using regional anesthesia techniques may prevent the development of persistent postsurgical pain (PPP), ultimately improving patient outcomes and enhancing overall quality of life in postsurgical patients. The purpose of this review is to describe the current literature regarding the role of regional anesthesia techniques in the perioperative setting to address and prevent PPP.

Recent Findings

Data was collected and analyzed using results from randomized controlled studies stratified into categories based on different surgical subspecialties. Conclusions were drawn from each surgical category regarding the role of regional anesthesia and/or local analgesia in acute and chronic pain management on the long-term results seen in the studies analyzed.

Summary

Preoperative consultations and optimized perioperative analgesia using regional anesthesia and local analgesia play a fundamental role preventing and treating postoperative pain after many types of surgery by managing pain in the acute setting to mitigate the future development of PPP. Additional studies in different surgical subspecialties are needed to confirm the role regional anesthesia plays in chronic postsurgical pain (CPSP) prevention.

Postoperative analgesic effectiveness of quadratus lumborum block: systematic review and meta-analysis for adult patients undergoing hip surgery

BACKGROUND

Quadratus lumborum block is a truncal block with several technique variations. It has been reported as providing effective analgesia for postoperative pain. The aim of this study is to determine the efficacy of the QL block in providing postoperative analgesia for hip surgery when compared with placebo or no block or other analgesic techniques.

METHODS

Randomized trials evaluating quadratus lumborum block benefits in elective hip surgery were sought. The primary outcome was the 24 h opioid requirement after surgery. Two independent reviewers selected the studies and extracted the data.

RESULTS

Thirteen randomized-controlled trials were included in this study. The included studies had significant heterogeneity regarding comparator groups; therefore, a limited quantitative analysis was undertaken for the comparison of QL block versus no block or placebo only. QL block reduced the opioid use by 15.78 (95% CI, 2.31 to 29.26) mg IME in the first postoperative 24 h compared with no block or placebo with no difference in static pain scores, pain grade was reduced by 2.95 (95% CI, 2.40 to 3.60) in the QL block group compared with placebo or no block in the first postoperative 24 h during movement.

CONCLUSIONS

Our meta-analysis indicates that QL block may be effective for analgesia in patients after hip surgery compared with placebo or no block. There is currently limited evidence comparing QL block with other analgesic techniques for hip surgery.

Effect of perineural bupivacaine infiltration on reducing inguinodynia in patients undergoing inguinal meshplasty - a randomized controlled trial

INTRODUCTION

Inguinodynia after inguinal meshplasty is a notable complication with an incidence of 13-37%. We wanted to determine if a perineural infiltration of bupivacaine given intraoperatively would reduce the incidence of immediate postoperative pain and inguinodynia.

METHODOLOGY

We have conducted a single-blinded randomized controlled trial including 100 patients with inguinal hernia. Patients in the control group received only spinal anaesthesia. The intervention group received perineural bupivacaine infiltration in addition to spinal anaesthesia. Intraoperatively Ilioinguinal, iliohypogastric, and genital branch of the genitofemoral nerve was identified and 2 mL of 0.5% bupivacaine was given perineurally along these identified nerves. Presence of inguinodynia, immediate post-operative pain scores using the Wong-Baker faces pain scale, duration of analgesics use, use of additional analgesics along with Paracetamol 500 mg tablet, and the length of hospital stay between the groups were recorded.

RESULTS

100 patients were randomized in the study, 49 in control and 51 in the intervention group. Both the group was comparable in terms of demographic characteristics. The intervention group had significantly lower median pain score at 3 h [4 ± 1.662 vs. 6 ± 1.55; p = .0001] and 6 h [4 ± 1.33 vs. 6 ± 1.307; p = .0001]. The incidence of inguinodynia did not significantly differ between the two groups (p-value = .12).

CONCLUSION

Intraoperative Perineural bupivacaine infiltration significantly reduces the immediate postoperative pain. However, there was no significant reduction in the incidence of inguinodynia or additional analgesic requirement.

Chest Wall Nerve Blocks for Cardiothoracic, Breast Surgery, and Rib-Related Pain

PURPOSE OF REVIEW

Perioperative analgesia in patients undergoing chest wall procedures such as cardiothoracic and breast surgeries or analgesia for rib fracture trauma can be challenging due to several factors: the procedures are more invasive, the chest wall innervation is complex, and the patient population may have multiple comorbidities increasing their susceptibility to the well-defined pain and opioid-related side effects. These procedures also carry a higher risk of persistent pain after surgery and chronic opioid use making the analgesia goals even more important.

RECENT FINDINGS

With advances in ultrasonography and clinical research, regional anesthesia techniques have been improving and newer ones with more applications have emerged over the last decade. Currently in cardiothoracic procedures, para-neuraxial and chest wall blocks have been utilized with success to supplement or substitute systemic analgesia, traditionally relying on opioids or thoracic epidural analgesia. In breast surgeries, paravertebral blocks, serratus anterior plane blocks, and pectoral nerve blocks have been shown to be effective in providing pain control, while minimizing opioid use and related side effects. Rib fracture regional analgesia options have also expanded and continue to improve.  Advances in regional anesthesia have tremendously improved multimodal analgesia and contributed to enhanced recovery after surgery protocols. This review provides the latest summary on the use and efficacy of chest wall blocks in cardiothoracic and breast surgery, as well as rib fracture-related pain and persistent postsurgical pain.

Postoperative Pain Management in Enhanced Recovery Pathways

Postoperative pain is a common but often inadequately treated condition. Enhanced recovery pathways (ERPs) are increasingly being utilized to standardize perioperative care and improve outcomes. ERPs employ multimodal postoperative pain management strategies that minimize opioid use and promote recovery. While traditional opioid medications continue to play an important role in the treatment of postoperative pain, ERPs also rely on a wide range of non-opioid pharmacologic therapies as well as regional anesthesia techniques to manage pain in the postoperative setting. The evidence for the use of these interventions continues to evolve rapidly given the increasing focus on enhanced postoperative recovery. This article reviews the current evidence and knowledge gaps pertaining to commonly utilized modalities for postoperative pain management in ERPs.

[Diagnostics and therapy of neuropathic pain]

Neuropathic pain is pain caused by a lesion or disease of the somatosensory nervous system. Scientific studies have shown that neuropathic pain is the result of complex altered signalling processes in the peripheral and central nervous system. Current forms of treatment of neuropathic pain are causally oriented but also aim at symptomatic analgesia by pharmacological and nonpharmacological methods. Furthermore, psychological pain management techniques are used in a supportive role. This review summarizes the contemporary diagnostics of neuropathic pain using frequent diseases as examples and presents the evidence from randomized controlled trials on the treatment of neuropathic pain. Treatment guidelines for pharmacological management of neuropathic pain include evidence-based use of antidepressants, anticonvulsants, opioids, capsaicin and lidocaine.

Pain in the Cancer Survivor

Recent decades have demonstrated significant strides in cancer screening, diagnostics and therapeutics. As such there have been dramatic changes in survival following a diagnosis of cancer.

Big Data in Studying Acute Pain and Regional Anesthesia

The digital transformation of healthcare is advancing, leading to an increasing availability of clinical data for research. Perioperative big data initiatives were established to monitor treatment quality and benchmark outcomes. However, big data analyses have long exceeded the status of pure quality surveillance instruments. Large retrospective studies nowadays often represent the first approach to new questions in clinical research and pave the way for more expensive and resource intensive prospective trials. As a consequence, the utilization of big data in acute pain and regional anesthesia research has considerably increased over the last decade. Multicentric clinical registries and administrative databases (e.g., healthcare claims databases) have collected millions of cases until today, on which basis several important research questions were approached. In acute pain research, big data was used to assess postoperative pain outcomes, opioid utilization, and the efficiency of multimodal pain management strategies. In regional anesthesia, adverse events and potential benefits of regional anesthesia on postoperative morbidity and mortality were evaluated. This article provides a narrative review on the growing importance of big data for research in acute postoperative pain and regional anesthesia.

[Prediction and prevention of chronic postoperative pain]

Chronic postoperative pain has been identified as a major medical and socioeconomic problem. A prevention of the chronification processes is potentially possible and preventive treatment could start early (e.g. preoperatively). So far, however, evidence for the effectiveness of preventive strategies is basically low. Important reasons for this dilemma are the lack of appropriate risk assessment as well as effective and mechanism-based preventive (procedure-sepcific) strategies for the chronification process, a lack of stratification of treatment approaches and a so far barely investigated combination of various treatment approaches. In this review article recent findings on the appropriate identification of patients at risk for developing postoperative chronic pain are presented, predictive models for the valid estimation of the individual risk of patients are assessed and studies on pharmaceutical and regional analgesia techniques influencing the pain chronification process are discussed. As a chronification process is, however, extremely complex and dynamic and also necessitates adaptation of the prevention during the course of the process, only combinations of treatment, interdisciplinary and if necessary even longer term approaches might be successful. Future studies are needed to address with which preventive treatment strategies and in which patients chronic pain after surgery can effectively be prevented.

Melatonin for preoperative and postoperative anxiety in adults

BACKGROUND

Anxiety in relation to surgery is a well-known problem. Melatonin offers an alternative treatment to benzodiazepines for ameliorating this condition in the preoperative and postoperative periods.

OBJECTIVES

To assess the effects of melatonin on preoperative and postoperative anxiety compared to placebo or benzodiazepines.

SEARCH METHODS

We searched the following databases on 10 July 2020: CENTRAL, MEDLINE, Embase, CINAHL, and Web of Science. For ongoing trials and protocols, we searched clinicaltrials.gov and the World Health Organization (WHO) International Clinical Trials Registry Platform.

SELECTION CRITERIA

We included randomized, placebo-controlled or standard treatment-controlled (or both) studies that evaluated the effects of preoperatively administered melatonin on preoperative or postoperative anxiety. We included adult patients of both sexes (15 to 90 years of age) undergoing any kind of surgical procedure for which it was necessary to use general, regional, or topical anaesthesia.

DATA COLLECTION AND ANALYSIS

One review author conducted data extraction in duplicate. Data extracted included information about study design, country of origin, number of participants and demographic details, type of surgery, type of anaesthesia, intervention and dosing regimens, preoperative anxiety outcome measures, and postoperative anxiety outcome measures.

MAIN RESULTS

We included 27 randomized controlled trials (RCTs), involving 2319 participants, that assessed melatonin for treating preoperative anxiety, postoperative anxiety, or both. Twenty-four studies compared melatonin with placebo. Eleven studies compared melatonin to a benzodiazepine (seven studies with midazolam, three studies with alprazolam, and one study with oxazepam). Other comparators in a small number of studies were gabapentin, clonidine, and pregabalin. No studies were judged to be at low risk of bias for all domains. Most studies were judged to be at unclear risk of bias overall. Eight studies were judged to be at high risk of bias in one or more domain, and thus, to be at high risk of bias overall. Melatonin versus placebo Melatonin probably results in a reduction in preoperative anxiety measured by a visual analogue scale (VAS, 0 to 100 mm) compared to placebo (mean difference (MD) -11.69, 95% confidence interval (CI) -13.80 to -9.59; 18 studies, 1264 participants; moderate-certainty evidence), based on a meta-analysis of 18 studies. Melatonin may reduce immediate postoperative anxiety measured on a 0 to 100 mm VAS compared to placebo (MD -5.04, 95% CI -9.52 to -0.55; 7 studies, 524 participants; low-certainty evidence), and may reduce delayed postoperative anxiety measured six hours after surgery using the State-Trait Anxiety Inventory (STAI) (MD -5.31, 95% CI -8.78 to -1.84; 2 studies; 73 participants; low-certainty evidence). Melatonin versus benzodiazepines (midazolam and alprazolam) Melatonin probably results in little or no difference in preoperative anxiety measured on a 0 to 100 mm VAS (MD 0.78, 95% CI -2.02 to 3.58; 7 studies, 409 participants; moderate-certainty evidence) and there may be little or no difference in immediate postoperative anxiety (MD -2.12, 95% CI -4.61 to 0.36; 3 studies, 176 participants; low-certainty evidence). Adverse events Fourteen studies did not report on adverse events. Six studies specifically reported that no side effects were observed, and the remaining seven studies reported cases of nausea, sleepiness, dizziness, and headache; however, no serious adverse events were reported. Eleven studies measured psychomotor and cognitive function, or both, and in general, these studies found that benzodiazepines impaired psychomotor and cognitive function more than placebo and melatonin. Fourteen studies evaluated sedation and generally found that benzodiazepine caused the highest degree of sedation, but melatonin also showed sedative properties compared to placebo. Several studies did not report on adverse events; therefore, it is not possible to conclude with certainty, from the data on adverse effects collected in this review, that melatonin is better tolerated than benzodiazepines.

AUTHORS' CONCLUSIONS

When compared with placebo, melatonin given as premedication (as tablets or sublingually) probably reduces preoperative anxiety in adults (measured 50 to 120 minutes after administration), which is potentially clinically relevant. The effect of melatonin on postoperative anxiety compared to placebo (measured in the recovery room and six hours after surgery) was also evident but was much smaller, and the clinical relevance of this finding is uncertain. There was little or no difference in anxiety when melatonin was compared with benzodiazepines. Thus, melatonin may have a similar effect to benzodiazepines in reducing preoperative and postoperative anxiety in adults.

Recommendations from the Italian intersociety consensus on Perioperative Anesthesa Care in Thoracic surgery (PACTS) part 2: intraoperative and postoperative care

Introduction

Anesthetic care in patients undergoing thoracic surgery presents specific challenges that require a multidisciplinary approach to management. There remains a need for standardized, evidence-based, continuously updated guidelines for perioperative care in these patients.

Methods

A multidisciplinary expert group, the Perioperative Anesthesia in Thoracic Surgery (PACTS) group, was established to develop recommendations for anesthesia practice in patients undergoing elective lung resection for lung cancer. The project addressed three key areas: preoperative patient assessment and preparation, intraoperative management (surgical and anesthesiologic care), and postoperative care and discharge. A series of clinical questions was developed, and literature searches were performed to inform discussions around these areas, leading to the development of 69 recommendations. The quality of evidence and strength of recommendations were graded using the United States Preventive Services Task Force criteria.

Results

Recommendations for intraoperative care focus on airway management, and monitoring of vital signs, hemodynamics, blood gases, neuromuscular blockade, and depth of anesthesia. Recommendations for postoperative care focus on the provision of multimodal analgesia, intensive care unit (ICU) care, and specific measures such as chest drainage, mobilization, noninvasive ventilation, and atrial fibrillation prophylaxis.

Conclusions

These recommendations should help clinicians to improve intraoperative and postoperative management, and thereby achieve better postoperative outcomes in thoracic surgery patients. Further refinement of the recommendations can be anticipated as the literature continues to evolve.

Enhanced Recovery With Paravertebral and Transversus Abdominis Plane Blocks in Microvascular Breast Reconstruction

Purpose:

We have shown previously that a preoperative paravertebral nerve block is associated with improved postoperative recovery in microvascular breast reconstruction. The purpose of this study was to compare the outcomes of a complete enhanced recovery after surgery (ERAS) protocol with complete regional anesthesia coverage to our traditional care with paravertebral block.

Patients and methods:

This was a retrospective cohort study of 83 patients who underwent autologous breast reconstruction by T.M.M. between May 2014 and February 2018 at a tertiary academic center. Patients in the ERAS group were additionally administered acetaminophen, non-steroidal anti-inflammatory drugs (NSAIDs), gabapentin, a transversus abdominis plane block (liposomal or plain bupivacaine), and primarily oral opioids postoperatively. The patients were mobilized earlier with more rapid diet progression. All patients received a preoperative paravertebral block.

Results:

Forty-four patients in the ERAS cohort were compared with 39 retrospective controls. The 2 groups were similar with respect to demographics and comorbidities. The ERAS cohort required significantly less opioids (291 vs 707 mg oral morphine equivalent, P < .0001) with unchanged postoperative pain scores and a shorter time to oral only opioid use (16.0 vs 78.2 hours, P < .0001). Median length of stay (3.20 vs 4.62, P < .0001) and time to independent ambulation (1.86 vs 2.88, P < .0001) were also significantly decreased in the ERAS cohort. Liposomal bupivacaine use did not significantly affect the results (P ⩾ .2).

Conclusions:

Implementation of a robust enhanced recovery protocol with complete regional anesthesia coverage was associated with significantly decreased opioid use despite unchanged pain scores, with improved markers of recovery including length of stay, time to oral only narcotics, and time to independent ambulation.

Drugs for preventing postoperative nausea and vomiting in adults after general anaesthesia: a network meta-analysis

BACKGROUND

Postoperative nausea and vomiting (PONV) is a common adverse effect of anaesthesia and surgery. Up to 80% of patients may be affected. These outcomes are a major cause of patient dissatisfaction and may lead to prolonged hospital stay and higher costs of care along with more severe complications. Many antiemetic drugs are available for prophylaxis. They have various mechanisms of action and side effects, but there is still uncertainty about which drugs are most effective with the fewest side effects.

OBJECTIVES

• To compare the efficacy and safety of different prophylactic pharmacologic interventions (antiemetic drugs) against no treatment, against placebo, or against each other (as monotherapy or combination prophylaxis) for prevention of postoperative nausea and vomiting in adults undergoing any type of surgery under general anaesthesia • To generate a clinically useful ranking of antiemetic drugs (monotherapy and combination prophylaxis) based on efficacy and safety • To identify the best dose or dose range of antiemetic drugs in terms of efficacy and safety SEARCH METHODS: We searched the Cochrane Central Register of Controlled Trials (CENTRAL), MEDLINE, Embase, the Cumulative Index to Nursing and Allied Health Literature (CINAHL), the World Health Organization International Clinical Trials Registry Platform (WHO ICTRP), ClinicalTrials.gov, and reference lists of relevant systematic reviews. The first search was performed in November 2017 and was updated in April 2020. In the update of the search, 39 eligible studies were found that were not included in the analysis (listed as awaiting classification).

SELECTION CRITERIA

Randomized controlled trials (RCTs) comparing effectiveness or side effects of single antiemetic drugs in any dose or combination against each other or against an inactive control in adults undergoing any type of surgery under general anaesthesia. All antiemetic drugs belonged to one of the following substance classes: 5-HT₃ receptor antagonists, D₂ receptor antagonists, NK₁ receptor antagonists, corticosteroids, antihistamines, and anticholinergics. No language restrictions were applied. Abstract publications were excluded.

DATA COLLECTION AND ANALYSIS

A review team of 11 authors independently assessed trials for inclusion and risk of bias and subsequently extracted data. We performed pair-wise meta-analyses for drugs of direct interest (amisulpride, aprepitant, casopitant, dexamethasone, dimenhydrinate, dolasetron, droperidol, fosaprepitant, granisetron, haloperidol, meclizine, methylprednisolone, metoclopramide, ondansetron, palonosetron, perphenazine, promethazine, ramosetron, rolapitant, scopolamine, and tropisetron) compared to placebo (inactive control). We performed network meta-analyses (NMAs) to estimate the relative effects and ranking (with placebo as reference) of all available single drugs and combinations. Primary outcomes were vomiting within 24 hours postoperatively, serious adverse events (SAEs), and any adverse event (AE). Secondary outcomes were drug class-specific side effects (e.g. headache), mortality, early and late vomiting, nausea, and complete response. We performed subgroup network meta-analysis with dose of drugs as a moderator variable using dose ranges based on previous consensus recommendations. We assessed certainty of evidence of NMA treatment effects for all primary outcomes and drug class-specific side effects according to GRADE (CINeMA, Confidence in Network Meta-Analysis). We restricted GRADE assessment to single drugs of direct interest compared to placebo.

MAIN RESULTS

We included 585 studies (97,516 randomized participants). Most of these studies were small (median sample size of 100); they were published between 1965 and 2017 and were primarily conducted in Asia (51%), Europe (25%), and North America (16%). Mean age of the overall population was 42 years. Most participants were women (83%), had American Society of Anesthesiologists (ASA) physical status I and II (70%), received perioperative opioids (88%), and underwent gynaecologic (32%) or gastrointestinal surgery (19%) under general anaesthesia using volatile anaesthetics (88%). In this review, 44 single drugs and 51 drug combinations were compared. Most studies investigated only single drugs (72%) and included an inactive control arm (66%). The three most investigated single drugs in this review were ondansetron (246 studies), dexamethasone (120 studies), and droperidol (97 studies). Almost all studies (89%) reported at least one efficacy outcome relevant for this review. However, only 56% reported at least one relevant safety outcome. Altogether, 157 studies (27%) were assessed as having overall low risk of bias, 101 studies (17%) overall high risk of bias, and 327 studies (56%) overall unclear risk of bias. Vomiting within 24 hours postoperatively Relative effects from NMA for vomiting within 24 hours (282 RCTs, 50,812 participants, 28 single drugs, and 36 drug combinations) suggest that 29 out of 36 drug combinations and 10 out of 28 single drugs showed a clinically important benefit (defined as the upper end of the 95% confidence interval (CI) below a risk ratio (RR) of 0.8) compared to placebo. Combinations of drugs were generally more effective than single drugs in preventing vomiting. However, single NK₁ receptor antagonists showed treatment effects similar to most of the drug combinations. High-certainty evidence suggests that the following single drugs reduce vomiting (ordered by decreasing efficacy): aprepitant (RR 0.26, 95% CI 0.18 to 0.38, high certainty, rank 3/28 of single drugs); ramosetron (RR 0.44, 95% CI 0.32 to 0.59, high certainty, rank 5/28); granisetron (RR 0.45, 95% CI 0.38 to 0.54, high certainty, rank 6/28); dexamethasone (RR 0.51, 95% CI 0.44 to 0.57, high certainty, rank 8/28); and ondansetron (RR 0.55, 95% CI 0.51 to 0.60, high certainty, rank 13/28). Moderate-certainty evidence suggests that the following single drugs probably reduce vomiting: fosaprepitant (RR 0.06, 95% CI 0.02 to 0.21, moderate certainty, rank 1/28) and droperidol (RR 0.61, 95% CI 0.54 to 0.69, moderate certainty, rank 20/28). Recommended and high doses of granisetron, dexamethasone, ondansetron, and droperidol showed clinically important benefit, but low doses showed no clinically important benefit. Aprepitant was used mainly at high doses, ramosetron at recommended doses, and fosaprepitant at doses of 150 mg (with no dose recommendation available). Frequency of SAEs Twenty-eight RCTs were included in the NMA for SAEs (10,766 participants, 13 single drugs, and eight drug combinations). The certainty of evidence for SAEs when using one of the best and most reliable anti-vomiting drugs (aprepitant, ramosetron, granisetron, dexamethasone, ondansetron, and droperidol compared to placebo) ranged from very low to low. Droperidol (RR 0.88, 95% CI 0.08 to 9.71, low certainty, rank 6/13) may reduce SAEs. We are uncertain about the effects of aprepitant (RR 1.39, 95% CI 0.26 to 7.36, very low certainty, rank 11/13), ramosetron (RR 0.89, 95% CI 0.05 to 15.74, very low certainty, rank 7/13), granisetron (RR 1.21, 95% CI 0.11 to 13.15, very low certainty, rank 10/13), dexamethasone (RR 1.16, 95% CI 0.28 to 4.85, very low certainty, rank 9/13), and ondansetron (RR 1.62, 95% CI 0.32 to 8.10, very low certainty, rank 12/13). No studies reporting SAEs were available for fosaprepitant. Frequency of any AE Sixty-one RCTs were included in the NMA for any AE (19,423 participants, 15 single drugs, and 11 drug combinations). The certainty of evidence for any AE when using one of the best and most reliable anti-vomiting drugs (aprepitant, ramosetron, granisetron, dexamethasone, ondansetron, and droperidol compared to placebo) ranged from very low to moderate. Granisetron (RR 0.92, 95% CI 0.80 to 1.05, moderate certainty, rank 7/15) probably has no or little effect on any AE. Dexamethasone (RR 0.77, 95% CI 0.55 to 1.08, low certainty, rank 2/15) and droperidol (RR 0.89, 95% CI 0.81 to 0.98, low certainty, rank 6/15) may reduce any AE. Ondansetron (RR 0.95, 95% CI 0.88 to 1.01, low certainty, rank 9/15) may have little or no effect on any AE. We are uncertain about the effects of aprepitant (RR 0.87, 95% CI 0.78 to 0.97, very low certainty, rank 3/15) and ramosetron (RR 1.00, 95% CI 0.65 to 1.54, very low certainty, rank 11/15) on any AE. No studies reporting any AE were available for fosaprepitant. Class-specific side effects For class-specific side effects (headache, constipation, wound infection, extrapyramidal symptoms, sedation, arrhythmia, and QT prolongation) of relevant substances, the certainty of evidence for the best and most reliable anti-vomiting drugs mostly ranged from very low to low. Exceptions were that ondansetron probably increases headache (RR 1.16, 95% CI 1.06 to 1.28, moderate certainty, rank 18/23) and probably reduces sedation (RR 0.87, 95% CI 0.79 to 0.96, moderate certainty, rank 5/24) compared to placebo. The latter effect is limited to recommended and high doses of ondansetron. Droperidol probably reduces headache (RR 0.76, 95% CI 0.67 to 0.86, moderate certainty, rank 5/23) compared to placebo. We have high-certainty evidence that dexamethasone (RR 1.00, 95% CI 0.91 to 1.09, high certainty, rank 16/24) has no effect on sedation compared to placebo. No studies assessed substance class-specific side effects for fosaprepitant. Direction and magnitude of network effect estimates together with level of evidence certainty are graphically summarized for all pre-defined GRADE-relevant outcomes and all drugs of direct interest compared to placebo in http://doi.org/10.5281/zenodo.4066353.

AUTHORS' CONCLUSIONS

We found high-certainty evidence that five single drugs (aprepitant, ramosetron, granisetron, dexamethasone, and ondansetron) reduce vomiting, and moderate-certainty evidence that two other single drugs (fosaprepitant and droperidol) probably reduce vomiting, compared to placebo. Four of the six substance classes (5-HT₃ receptor antagonists, D₂ receptor antagonists, NK₁ receptor antagonists, and corticosteroids) were thus represented by at least one drug with important benefit for prevention of vomiting. Combinations of drugs were generally more effective than the corresponding single drugs in preventing vomiting. NK₁ receptor antagonists were the most effective drug class and had comparable efficacy to most of the drug combinations. 5-HT₃ receptor antagonists were the best studied substance class. For most of the single drugs of direct interest, we found only very low to low certainty evidence for safety outcomes such as occurrence of SAEs, any AE, and substance class-specific side effects. Recommended and high doses of granisetron, dexamethasone, ondansetron, and droperidol were more effective than low doses for prevention of vomiting. Dose dependency of side effects was rarely found due to the limited number of studies, except for the less sedating effect of recommended and high doses of ondansetron. The results of the review are transferable mainly to patients at higher risk of nausea and vomiting (i.e. healthy women undergoing inhalational anaesthesia and receiving perioperative opioids). Overall study quality was limited, but certainty assessments of effect estimates consider this limitation. No further efficacy studies are needed as there is evidence of moderate to high certainty for seven single drugs with relevant benefit for prevention of vomiting. However, additional studies are needed to investigate potential side effects of these drugs and to examine higher-risk patient populations (e.g. individuals with diabetes and heart disease).

Managing rebound pain after regional anesthesia

Rebound pain after regional anesthesia can be defined as transient acute postoperative pain that ensues following resolution of sensory blockade, and is clinically significant, either with regard to the intensity of pain or the impact on psychological well-being, quality of recovery, and activities of daily living. Current evidence suggests that it represents an unmasking of the expected nociceptive response in the absence of adequate systemic analgesia, rather than an exaggerated hyperalgesic phenomenon induced by local anesthetic neural blockade. In the majority of patients, it does not appear to significantly impact cumulative postoperative opioid consumption, quality of recovery, or patient satisfaction, and is not associated with longer-term sequelae such as persistent post-surgical pain. Nevertheless, it must be considered whenever regional anesthesia is incorporated into perioperative management. Strategies to mitigate the impact of rebound pain include routine prescribing of a systemic multimodal analgesic regimen, as well as patient education on appropriate expectations regarding block offset and expected surgical pain, and timely initiation of analgesic medication. Prolonging the duration of action of regional anesthesia with continuous catheter techniques or local anesthetic adjuncts may also help alleviate rebound pain, although further research is required to confirm this.

Topical anaesthesia plus intracameral lidocaine versus topical anaesthesia alone for phacoemulsification cataract surgery in adults

BACKGROUND

Phacoemulsification cataract surgery is usually performed in adults under local anaesthesia. Topical anaesthesia, which involves instilling anaesthetic drops to the ocular surface prior to and during surgery, has found large acceptance internationally. It is safe and allows for rapid patient turnover and visual recovery. Some surgeons have supplemented topical anaesthesia with intracameral lidocaine, reasoning that this may further reduce intraoperative pain, particularly during surgical stages involving manipulation of intraocular structures and rapid changes in fluid dynamics. This review, originally published in 2006 and updated in 2020, explores the efficacy and safety of using supplementary intracameral lidocaine in phacoemulsification cataract surgery.

OBJECTIVES

To assess whether supplementing topical anaesthesia with intracameral lidocaine for phacoemulsification cataract surgery in adults reduces intraoperative and postoperative pain, and to assess differences in participant satisfaction, need for additional intraoperative anaesthesia, surgeon satisfaction, measures of intraocular toxicity, and adverse effects attributable to choice of anaesthesia.

SEARCH METHODS

We searched CENTRAL, MEDLINE, Embase, LILACS BIREME iAH, and six trial registries on 4 February 2020. We also searched the reference lists of identified studies. There were no language restrictions.

SELECTION CRITERIA

We included only randomized controlled trials (RCTs) where participants underwent phacoemulsification for age-related cataract under topical anaesthesia with or without intracameral lidocaine either in two eyes of the same participant, or in different participants. We also included studies that used oral or intravenous sedation in addition to local anaesthesia.

DATA COLLECTION AND ANALYSIS

Two review authors independently extracted data and assessed trial methodological quality using standard Cochrane procedures.

MAIN RESULTS

We identified five new RCTs in this updated review. We included a total of 13 trials in the review, conducted in the UK, the USA, Australia, Italy, Canada, Taiwan, Singapore, India, and Pakistan, and comprising 2388 eyes of 2355 participants (one study was a paired-eye study with each participant acting as their own control). The age range of participants was 34 to 95 years. We excluded studies that only included low-risk participants and excluded more difficult operative cases, for example hard lens nuclei or small pupils. We excluded studies assessing only participants with Fuchs' endothelial dystrophy. We judged one study as at high risk for selection bias. We assessed five studies as having an unclear risk of bias for random sequence generation and seven studies an unclear risk of bias for allocation concealment. We judged three studies as at high risk of performance bias, as the surgeon was not blinded, and two studies as at unclear risk of bias for this domain. No studies were judged as at high risk for detection bias, but five studies were judged to have an unclear risk of bias for this domain. We judged all 13 included studies to have a low risk of attrition bias and an unclear risk of reporting bias. Data from eight RCTs favoured topical anaesthesia plus intracameral lidocaine 0.5% to 1% over topical anaesthesia alone for reducing intraoperative pain when measured using a 10-point visual analogue scale, analysed as a continuous outcome. Mean pain score was 0.26 lower in the supplemental intracameral lidocaine group (95% confidence interval (CI) -0.39 to -0.13, 1692 eyes, moderate-quality evidence). Data from seven RCTs favoured supplemental intracameral lidocaine for reducing intraoperative pain when measured as a dichotomous outcome. The odds ratio of experiencing any pain was 0.40 versus the topical anaesthesia-only group (95% CI 0.29 to 0.57, 1268 eyes, moderate-quality evidence). Data from four RCTs did not show any additional benefit on postoperative pain when measured using a 10-point visual analogue scale (mean difference 0.12 points, 95% CI -0.29 to 0.05, 751 eyes, moderate-quality evidence). The impact on participant satisfaction was uncertain as only one small study investigated this outcome. The study suggested no difference between groups (mean difference 0.1 points, 95% CI -0.47 to 0.27, 60 eyes, low-quality evidence). Data from seven RCTs did not demonstrate a difference between groups in the need for additional intraoperative anaesthesia (odds ratio 0.88, 95% CI 0.56 to 1.39, 1194 eyes of 1161 participants; low-quality evidence), although this result is uncertain. A variety of measures were reported relating to possible intraocular toxicity. Data from four RCTs did not demonstrate a difference between groups in mean percentage corneal endothelial cell count change from pre- to postoperatively (mean difference 0.89%, 95% CI -1.12% to 2.9%, 254 eyes of 221 participants, moderate-quality evidence). Synthesis of the evidence from eight RCTs identified no difference in intraoperative adverse events between groups (odds ratio 1.00, 95% CI 0.32 to 3.16, 1726 eyes, low-quality evidence). This result should be interpreted with caution, mainly due to a lack of clear definitions of adverse events, low numbers of events, heterogeneity between studies, and large confidence intervals. Large observational studies may have been more appropriate for looking at this outcome.

AUTHORS' CONCLUSIONS

There is moderate-quality evidence that supplementation of topical anaesthesia with intracameral lidocaine 0.5% to 1% for phacoemulsification cataract surgery in adults reduces participant perception of intraoperative pain. The odds of experiencing any pain (as opposed to no pain) were 60% less for the topical anaesthesia plus intracameral lidocaine group versus the topical anaesthesia-only group. However, the numerical amplitude of the effect may not be of great clinical significance on the continuous pain score scale. Generally, the pain scores were consistently low for both techniques. We found moderate-quality evidence that there is no additional benefit of intracameral lidocaine on postoperative pain. There is insufficient evidence to determine the impact on participant satisfaction and need for additional intraoperative anaesthesia due to low-quality evidence. There is moderate-quality evidence that intracameral lidocaine supplementation does not increase measures of intraocular toxicity, specifically loss of corneal endothelial cells. There is low-quality evidence that the incidence of intraoperative adverse events is unchanged with intracameral lidocaine supplementation, but as RCTs are not the optimum medium for looking at this, this result should be interpreted with caution. Further research specifically investigating the adverse effects of intracameral anaesthesia might help to better determine its safety profile. Economic evaluations would also be useful for detailing cost implications.

Pectoral nerve block as the sole anesthetic technique for a modified radical mastectomy in a comorbid patient

Breast surgery operations are generally performed by general anesthesia. In order to decrease postoperative pain, regional anesthesia is usually combined with general anesthesia. Pectoral nerve blocks is a novel technique to provide perioperative and postoperative pain control for patients underwent breast surgery. We performed pectoral nerve block I and pectoral nerve block II as a sole anesthetic technique with sedation by dexmedetomidine for modified radical mastectomy, for a 75-year-old female patient with multiple diseases. Pectoral nerve blocks with sedation could be a good technique for breast surgery than general anesthesia in comorbid patients.

Transient neurological symptoms (TNS) following spinal anaesthesia with lidocaine versus other local anaesthetics in adult surgical patients: a network meta-analysis

BACKGROUND

Spinal anaesthesia has been implicated as one of the possible causes of neurological complications following surgical procedures. This painful condition, occurring during the immediate postoperative period, is termed transient neurological symptoms (TNS) and is typically observed after the use of spinal lidocaine. Alternatives to lidocaine that can provide high-quality anaesthesia without TNS development are needed. This review was originally published in 2005, and last updated in 2009.

OBJECTIVES

To determine the frequency of TNS after spinal anaesthesia with lidocaine and compare it with other types of local anaesthetics by performing a meta-analysis for all pair-wise comparisons, and conducting network meta-analysis (NMA) to rank interventions.

SEARCH METHODS

We searched CENTRAL, MEDLINE, Elsevier Embase, and LILACS on 25 November 2018. We searched clinical trial registries and handsearched the reference lists of trials and review articles.

SELECTION CRITERIA

We included randomized and quasi-randomized controlled trials comparing the frequency of TNS after spinal anaesthesia with lidocaine to other local anaesthetics. Studies had to have two or more arms that used distinct local anaesthetics (irrespective of the concentration and baricity of the solution) for spinal anaesthesia in preparation for surgery. We included adults who received spinal anaesthesia and considered all pregnant participants as a subgroup. The follow-up period for TNS was at least 24 hours.

DATA COLLECTION AND ANALYSIS

Four review authors independently assessed studies for inclusion. Three review authors independently evaluated the quality of the relevant studies and extracted the data from the included studies. We performed meta-analysis for all pair-wise comparisons of local anaesthetics, as well as NMA. We used an inverse variance weighting for summary statistics and a random-effects model as we expected methodological and clinical heterogeneity across the included studies resulting in varying effect sizes between studies of pair-wise comparisons. The NMA used all included studies based on a graph theoretical approach within a frequentist framework. Finally, we ranked the competing treatments by P scores.

MAIN RESULTS

The analysis included 24 trials reporting on 2226 participants of whom 239 developed TNS. Two studies are awaiting classification and one is ongoing. Included studies mostly had unclear to high risk of bias. The NMA included 24 studies and eight different local anaesthetics; the number of pair-wise comparisons was 32 and the number of different pair-wise comparisons was 11. This analysis showed that, compared to lidocaine, the risk ratio (RR) of TNS was lower for bupivacaine, levobupivacaine, prilocaine, procaine, and ropivacaine with RRs in the range of 0.10 to 0.23 while 2-chloroprocaine and mepivacaine did not differ in terms of RR of TNS development compared to lidocaine. Pair-wise meta-analysis showed that compared with lidocaine, most local anaesthetics were associated with a reduced risk of TNS development (except 2-chloroprocaine and mepivacaine) (bupivacaine: RR 0.16, 95% confidence interval (CI) 0.09 to 0.28; 12 studies; moderate-quality evidence; 2-chloroprocaine: RR 0.09, 95% CI 0.01 to 1.51; 2 studies; low-quality evidence; levobupivacaine: RR 0.13, 95% CI 0.02 to 0.69; 2 studies; low-quality evidence; mepivacaine: RR 1.01, 95% CI 0.18 to 5.82; 4 studies; very low-quality evidence; prilocaine: RR 0.18, 95% CI 0.07 to 0.49; 4 studies; moderate-quality evidence; procaine: RR 0.14, 95% CI 0.04 to 0.52; 2 studies; moderate-quality evidence; ropivacaine: RR 0.10, 95% CI 0.01 to 0.78; 2 studies; low-quality evidence). We were unable to perform any of our planned subgroup analyses due to the low number of TNS events.

AUTHORS' CONCLUSIONS

Results from both NMA and pair-wise meta-analysis indicate that the risk of developing TNS after spinal anaesthesia is lower when bupivacaine, levobupivacaine, prilocaine, procaine, and ropivacaine are used compared to lidocaine. The use of 2-chloroprocaine and mepivacaine had a similar risk to lidocaine in terms of TNS development after spinal anaesthesia. Patients should be informed of TNS as a possible adverse effect of local anaesthesia with lidocaine and the choice of anaesthetic agent should be based on the specific clinical context and parameters such as the expected duration of the procedure and the quality of anaesthesia. Due to the very low- to moderate-quality evidence (GRADE), future research efforts in this field are required to assess alternatives to lidocaine that would be able to provide high-quality anaesthesia without TNS development. The two studies awaiting classification and one ongoing study may alter the conclusions of the review once assessed.

Medicaid insurance status predicts postoperative mortality after total knee arthroplasty in state inpatient databases

Aim: Medicaid versus private primary insurance status may predict in-hospital mortality and morbidity after total knee arthroplasty (TKA). Materials & methods: Regression models were used to test our hypothesis in patients in the State Inpatient Database (SID) from five states who underwent primary TKA from January 2007 to December 2014. Results: Medicaid patients had greater odds of in-hospital mortality (odds ratio [OR]: 1.73; 95% CI: 1.01-2.95), greater odds of any postoperative complications (OR: 1.25; 95% CI: 1.18-1.33), experience longer lengths of stay (OR: 1.09; 95% CI: 1.08-1.10) and higher total charges (OR: 1.03; 95% CI: 1.02-1.04). Conclusion: Medicaid insurance status is associated with higher in-hospital mortality and morbidity in patients after TKA compared with private insurance.

PECS II block is associated with lower incidence of chronic pain after breast surgery

Background

Breast cancer is complicated by a high incidence of chronic postoperative pain (25%–60%). Regional anesthesia might play an important role in lowering the incidence of chronic pain; however it is not known if the pectoral nerve block (PECS block), which is commonly used for breast surgery, is able to prevent this complication. Our main objective was therefore to detect any association between the PECS block and chronic pain at 3, 6, 9, and 12 months in patients undergoing breast surgery.

Methods

We conducted a prospective, monocentric, observational study. We enrolled 140 consecutive patients undergoing breast surgery and divided them in patients receiving a PECS block and general anesthesia (PECS group) and patients receiving only general anesthesia (GA group). Then we considered both intraoperative variables (intravenous opioids administration), postoperative data (pain suffered by the patients during the first 24 postoperative hours and the need for additional analgesic administration) and development and persistence of chronic pain (at 3, 6, 9, and 12 mo).

Results

The PECS group had a lower incidence of chronic pain at 3 months (14.9% vs. 31.8%, P = 0.039), needed less intraoperative opioids (fentanyl 1.61 μg/kg/hr vs. 3.3 μg/kg/hr, P < 0.001) and had less postoperative pain (3 vs. 4, P = 0.017).

Conclusions

The PECS block might play an important role in lowering incidence of chronic pain, but further studies are needed.

Chronified Pain Following Operative Procedures

BACKGROUND

Over 18 million operative procedures are performed each year in Germany alone. Approximately 10% of surgical patients develop moderate to severe chronic post-surgical pain (CPSP), which can severely impair their quality of life. The pain must persist for at least three months to be called chronic; pain that arises after a symptom-free interval is not excluded. The perioperative use of local anesthetic agents may lessen the incidence of CPSP.

METHODS

We selectively reviewed the pertinent literature, including two current Cochrane Reviews. Local and regional anesthetic techniques are discussed, as is the intravenous administration of lidocaine.

RESULTS

The main risk factors for CPSP are pre-existing (preoperative) chronic pain, opioid intake, a pain-related catastrophizing tendency, intraoperative nerve injury, and severe acute postoperative pain. CPSP is reported to be especially common after thoracic surgery, breast surgery, amputations, and orthopedic procedures. Local and regional anesthetic techniques have been shown to significantly lower the incidence of CPSP after thoracotomy (number needed to treat for an additional beneficial outcome [NNTB] = 7), breast cancer surgery (NNTB = 7), and cesarean section (NNTB = 19). Intravenous lidocaine also lowers the incidence of CPSP after various types of procedures.

CONCLUSION

Local and regional anesthetic techniques and intravenous lidocaine lower the incidence of CPSP after certain types of operative procedures. The intravenous administration of lidocaine to prevent CPSP is off label and requires the patient's informed consent. The evidence for the measures presented here is of low to medium quality.