Do Surgical Patients Benefit from Perioperative Gabapentin/Pregabalin? A Systematic Review of Efficacy and Safety

Designing intelligent anesthesia for a changing patient demographic: a consensus statement to provide guidance for specialist and non-specialist anesthetists written by members of and endorsed by the Society for Obesity and Bariatric Anaesthesia (SOBA)

BACKGROUND

As a result of the increasing prevalence of obesity in the UK, anesthetists are increasingly encountering overweight and obese patients in routine practice. There is currently a paucity of evidence to guide best clinical practice for anesthetists managing overweight and obese patients. The current guidelines from the Association of Anaesthetists of Great Britain and Ireland (AAGBI), entitled Peri-Operative Management of the Morbidly Obese Patient, give an excellent overview of organizational issues, but leave much clinical detail to the discretion of the individual clinician.

METHODS

In May 2010, a panel of experts convened to develop consensus on anesthesia of overweight, obese and morbidly obese patients, in consultation with the Society for Obesity and Bariatric Anaesthesia (SOBA). All Panel members are practicing clinicians from recognized bariatric surgical training centers and have extensive experience of anesthesia for obese patients. This statement aims to provide guiding principles on best practice for this challenging patient demographic, and to increase awareness of current issues so that these can be addressed more appropriately.

RESULTS

In this document, we emphasize key principles for best practice, rather than giving prescriptive guidance and specific regimens for all clinical eventualities. We provide evidence-based justification for best-practice techniques, where this exists. In areas for which there is no evidence, but there is clear consensus, we offer this as guidance. We also aim to dispel misconceptions that have arisen in the anesthetic practice of overweight, obese, and morbidly obese patients.

CONCLUSION

Ultimately, the choice of specific technique depends on clinician experience, patient characteristics, and center facilities. As well as providing guiding principles for anesthesia, this consensus statement also highlights other areas where anesthetists can contribute towards the enhanced recovery and overall quality of patient care.

Long-term use of gabapentin for musculoskeletal disease and trauma in three cats

Gabapentin has been widely used in human medicine to control acute and chronic pain. Although the exact mechanism of action has yet to be determined, its use in veterinary medicine is increasing. The clinical use of gabapentin for analgesia in cats has been reported in review articles and one case report. Managing chronic pain, particularly in the feline patient, poses a challenge to veterinary surgeons. This report details the long-term use of gabapentin for musculoskeletal pain or head trauma in three cats. All cats received gabapentin for several months at an average dose of 6.5 mg/kg q12h. Clinical signs suggestive of pain, such as aggression, avoiding human interaction and loss of appetite, were observed to decrease with the administration of gabapentin, used as part of an analgesia regime or as sole medication. Long-term follow-up with the owners of all cats indicated that satisfactory pain management was achieved, administration was easy and no obvious side effects during the period of administration occurred. We conclude that long-term treatment with gabapentin is of potential benefit in controlling pain in cases of head trauma, as well as musculoskeletal disease. It may provide a valuable adjunct for the management of chronic pain in cats and should be investigated further for its clinical use and safety.

Effect of Two Different Doses of Gabapentin on the Intraocular Pressure and Hemodynamic Stress Responses to Laryngoscopy and Tracheal Intubation

Background. The stress response to laryngoscopy and intubation causes an undesirable increase in heart rate, blood pressure, and intraocular pressure. This study was designed to compare the effect of two doses of gabapentin on the stress response to laryngoscopy and intubation. Patients and Methods. (ASA I and II) 60 patients, aged from 18 to 60 years undergoing elective eye surgery requiring endotracheal intubation, were randomly allocated into 3 groups, 20 patients each. 2 hours before the surgery, group I received oral placebo, and groups II and III received oral gabapentin 800 mg and 1200 mg, respectively. Heart rate (HR), mean arterial pressure (MAP), and intraocular pressure (IOP) were measured before and after induction of anesthesia, immediately after, 5 minutes, and 10 minutes after intubation. Results. Gabapentin 1200 mg prevented the increase in HR, MAP, and IOP, secondary to laryngoscopy and intubation, and kept them below the baseline till 10 minutes after intubation (), while with gabapentin 800 mg, the increase in HR, MAP, and IOP was nonsignificant () and returned to levels below the baseline at 5 and 10 minutes after intubation. Conclusion. Preoperative gabapentin 1200 mg effectively prevented the stress response to laryngoscopy and intubation; meanwhile, gabapentin 800 mg only prevented significant stress response.

Perioperative interventions to reduce chronic postsurgical pain

Approximately 10% of patients following a variety of surgeries develop chronic postsurgical pain. Reducing chronic postoperative pain is especially important to reconstructive surgeons because common operations such as breast and limb reconstruction have even higher risk for developing chronic postsurgical pain. Animal studies of posttraumatic nerve injury pain demonstrate that there is a critical time frame before and immediately after nerve injury in which specific interventions can reduce the incidence and intensity of chronic neuropathic pain behaviors-so called "preventative analgesia." In animal models, perineural local anesthetic, systemic intravenous local anesthetic, perineural clonidine, systemic gabapentin, systemic tricyclic antidepressants, and minocycline have each been shown to reduce pain behaviors days to weeks after treatment. The translation of this work to humans also suggests that brief perioperative interventions may protect patients from developing new chronic postsurgical pain. Recent clinical trial data show that there is an opportunity during the perioperative period to dramatically reduce the incidence and severity of chronic postsurgical pain. The surgeon, working with the anesthesiologist, has the ability to modify both early and chronic postoperative pain by implementing an evidence-based preventative analgesia plan.

Post-thoracotomy pain syndrome: assessment and intervention

Surgery is a cornerstone of treatment in early-stage non-small cell lung cancer. Chronic postoperative thoracotomy pain, post-thoracotomy pain syndrome (PTPS), is a condition occurring in 50% of postsurgical patients with lung cancer and is largely unrecognized. This article examines the diagnosis and treatment of PTPS to assist oncology nurses in providing better care to this patient population. Post-thoracotomy pain in patients with lung cancer may be under-reported and undertreated. Causes from the thoracotomy can be trauma and compression to the intercoastal nerves, fractured and compressed ribs, inflammation of the chest muscles, atrophy of chest muscles, or scar tissue rubbing. This article examines the diagnosis and treatment of PTPS to assist oncology nurses in providing better care to this patient population. If left untreated, chronic pain can have a deleterious effect on patients' recovery and overall well-being. Oncology nurses should be aware of the signs and symptoms of PTPS so that more patients are diagnosed and choose to seek treatment.

Effects of Preoperative Gabapentin on Postoperative Pain after Radical Retropubic Prostatectomy

Objective:

The impact of preoperative gabapentin on tramadol consumption using patient-controlled analgesia (PCA) and postoperative pain was assessed in patients undergoing radical retropubic prostatectomy (RRP).

Methods:

In this prospective, randomized trial, 51 patients undergoing RRP were randomized into two groups: the gabapentin group received 900 mg gabapentin orally 2 h before surgery; the control group did not receive gabapentin. Postoperative analgesia was provided by tramadol PCA. Pain was assessed using a visual analogue scale for 24 h, postoperatively.

Results:

Mean cumulative tramadol consumption at 24 h was comparable in the two groups. Pain scores at 45 min, 60 min and 2 h postoperatively, and the number of patients who required rescue analgesia, were significantly lower in the gabapentin group than in the control group. Side-effects were similar in the two groups.

Conclusions:

Preoperative administration of 900 mg gabapentin did not decrease tramadol consumption, but was associated with lower pain scores in the early postoperative phase and a reduced need for rescue analgesia, compared with controls, in patients undergoing RRP.

Contemporary perioperative care strategies

Background

Historically, the preoperative and postoperative care of patients with gastrointestinal cancer was provided by surgeons. Contemporary perioperative care is a truly multidisciplinary endeavour with implications for cancer-specific outcomes.

Methods

A literature review was performed querying PubMed and the Cochrane Library for articles published between 1966 to 2012 on specific perioperative interventions with the potential to improve the outcomes of surgical oncology patients. Keywords used were: fast-track, enhanced recovery, accelerated rehabilitation, multimodal and perioperative care. Specific interventions included normothermia, hyperoxygenation, surgical-site infection, skin preparation, transfusion, non-steroidal anti-inflammatory drugs, thromboembolism and antibiotic prophylaxis, laparoscopy, radiotherapy, perioperative steroids and monoclonal antibodies. Included articles had to be randomized controlled trials, prospective or nationwide series, or systematic reviews/meta-analyses, published in English, French or German.

Results

Important elements of modern perioperative care that improve recovery of patients and outcomes in surgical oncology include accelerated recovery pathways, thromboembolism and antibiotic prophylaxis, hyperoxygenation, maintenance of normothermia, avoidance of blood transfusion and cautious use of non-steroidal anti-inflammatory drugs, promotion of laparoscopic surgery, chlorhexidine–alcohol skin preparation and multidisciplinary meetings to determine multimodal therapy.

Conclusion

Multidisciplinary management of perioperative patient care has improved outcomes.

Patient directed self management of pain (PaDSMaP) compared to treatment as usual following total knee replacement: study protocol for a randomized controlled trial

BACKGROUND

In 2009, 665 patients underwent total knee replacements (TKRs) at the Norfolk and Norwich University Hospitals NHS Foundation Trust (NNUH), representing nearly 1% of the national total. Pain control following the operation can be poor, and this can cause poor mobilization and potential long-term adverse events. Although high levels of pain are not associated with patient dissatisfaction, brief periods of pain may lead to neuronal remodeling and sensitization. Patient controlled oral analgesia (PCOA) may improve pain relief; however, the evidence to date has been inconclusive. Patient directed self management of pain (PaDSMaP) is a single center randomized controlled trial, which aims to establish if patient self-medication improves, or is equivalent to, treatment as usual and to create an educational package to allow implementation elsewhere.

METHODS/DESIGN

Patients eligible for a TKR will be recruited and randomized in the outpatient clinic. All patients will undergo their operations according to normal clinical practice but will be randomized into two groups. Once oral medication has commenced, one group will have pain relief administered by nursing staff in the usual way (treatment as usual; TAU), whilst the second group will self manage their pain medication (patient directed self management of pain; PaDSMaP). Those recruited for self-medication will undergo a training program to teach the use of oral analgesics according to the World Health Organization (WHO) pain cascade and how to complete the study documentation. The primary endpoint of the trial is the visual analogue scale (VAS) pain score at 3 days or discharge, whichever is sooner. The follow-up time is 6 weeks with a planned trial period of 3 years. The secondary objectives are satisfaction with the management of patient pain post-operatively whilst an inpatient after primary TKR; overall pain levels and pain on mobilization; satisfaction with pain management information provided; global outcomes, such as quality of life (QOL) and activities of daily living (ADLs); time to mobilization and whether time to mobilization is associated with frequency of adverse events, improvements in QOL, ADLs and pain at 6 weeks after the operation; incidence of adverse events; quantity and type of pain medications used whilst an inpatient; the acceptability of PaDSMaP and/or TAU protocols for patients and the healthcare professionals involved in their care; to investigate the health-related costs associated with a PaDSMaP system; and to estimate the cost-effectiveness of PaDSMaP compared to TAU.

TRIAL REGISTRATION

Current Controlled Trials ISRCTN: 10868989.

Acute pain management in the opioid-tolerant patient

SUMMARY Opioid use is increasing worldwide leading to an increasing number of opioid-tolerant patients requiring acute pain management after surgery, trauma and acute diseases. Provision of analgesia in opioid-tolerant patients is complex due to the pharmacological effects of long-term opioid exposure, but also due to pre-existing pain states, comorbidities and psychosocial issues. Acute pain management in these patients is governed by the principles of provision of good analgesia, avoidance of withdrawal and organized discharge. Pain relief needs to be achieved by the use of multimodal analgesia, including regional anesthetic techniques and, if needed, opioids in increased doses. Withdrawal is best prevented by ongoing opioid substitution at previously established doses. Discharge planning requires multidisciplinary input and good communication with all healthcare providers involved.

Recent advances in the pharmaceutical management of pain

Pain is an unpleasant sensory and emotional experience for patients. Management of pain is the most frequent issue encountered by clinicians and treatment is usually with pharmacological therapy. This review discusses recent pharmaceutical advances in pain management with respect to new modes of analgesic delivery, as well as new analgesic agents and adjuvants that are currently being investigated for their analgesic properties. New modes of administration include transdermal delivery in the form of skin patches, transmucosal delivery, inhalational administration, various patient-controlled devices and extended-release analgesic formulations. Up-to-date research is presented on classical analgesics, such as opioids, anti-inflammatory agents, including cyclo-oxygenase-2 inhibitors and paracetamol (acetaminophen), local anesthetics and ketamine. In addition, newer agents such as antidepressants and antiepileptic drugs as well as medicinal cannabinoids are discussed. As our understanding of the multiple pain pathways involved in the pathogenesis of pain expands, further compounds with analgesic properties will be developed.

Fast-track hip and knee arthroplasty: clinical and organizational aspects

Fast-track hip and knee arthroplasty aims at giving the patients the best available treatment at all times, being a dynamic entity. Fast-track combines evidence-based, clinical features with organizational optimization including a revision of traditions resulting in a streamlined pathway from admission till discharge – and beyond. The goal is to reduce morbidity, mortality and functional convalescence with an earlier achievement of functional milestones including functional discharge criteria with subsequent reduced length of stay and high patient satisfaction. Outcomes are traditionally measured as length of stay; safety aspects in the form of morbidity/mortality; patient satisfaction; and – as a secondary parameter – economic savings. Optimization of the clinical aspects include focusing on analgesia; DVT-prophylaxis; mobilization; care principles including functional discharge criteria; patient-characteristics to predict outcome; and traditions which may be barriers in optimizing outcomes. Patients should be informed and motivated to be active participants and their expectations should be modulated in order to improve satisfaction. Also, organizational aspects need to be analyzed and optimized. New logistical approaches should be implemented; the ward ideally (re)structured to only admit arthroplasties; the staff educated to have a uniform approach; extensive preoperative information given including discharge criteria and intended length of stay. This thesis includes 9 papers on clinical and organizational aspects of fast-track hip and knee arthroplasty (I–IX). A detailed description of the fast-track set-up and its components is provided. Major results include identification of patient characteristics to predict length of stay and satisfaction with different aspects of the hospital stay (I); how to optimize analgesia by using a compression bandage in total knee arthroplasty (II); the clinical and organizational set-up facilitating or acting as barriers for early discharge (III); safety aspects following fast-track in the form of few readmissions in general (IV) and few thromboembolic complications in particular (V); feasibility studies showing excellent outcomes following fast-track bilateral simultaneous total knee arthroplasty (VI) and non-septic revision knee arthroplasty (VII); how acute pain relief in total hip arthroplasty is not enhanced by the use of local infiltration analgesia when multi-modal opioid-sparing analgesia is given (VIII); and a detailed description of which clinical and organizational factors detain patients in hospital following fast-track hip and knee arthroplasty (IX). Economic savings following fast-track hip and knee arthroplasty is also documented in studies, reviews, metaanalyses and Cochrane reviews – including the present fast-track (ANORAK). In conclusion, the published results (I–IX) provide substantial, important new knowledge on clinical and organizational aspects of fast-track hip and knee arthroplasty – with concomitant documented high degrees of safety (morbidity/mortality) and patient satisfaction. Future research strategies are multiple and include both research strategies as efforts to implement the fast-track methodology on a wider basis. Research areas include improvements in pain treatment, blood saving strategies, fluid plans, reduction of complications, avoidance of tourniquet and concomitant blood loss, improved early functional recovery and muscle strengthening. Also, improvements in information and motivation of the patients, preoperative identification of patients needing special attention and detailed economic studies of fast- track are warranted.

A protocol for a systematic review for perioperative pregabalin use

BACKGROUND

Perioperative pain management has recently been revolutionized with the recognition of novel mechanisms and introduction of newer drugs. Many randomized trials have studied the use of the gabapentinoid anti-epileptic, pregabalin, in acute pain. Published systematic reviews suggest that using pregabalin for perioperative pain management may decrease analgesic requirements and pain scores, at the expense of troublesome side effects. A major limitation of the extant reviews is the lack of rigorous investigation of clinical characteristics that would maximize the benefit harms ratio in favor of surgical patients. We posit that effects of pregabalin for perioperative pain management vary by the type of surgical pain model and propose this systematic review protocol to update previous systematic reviews and investigate the heterogeneity in findings across subgroups of surgical pain models.

METHODS/DESIGN

Using a peer-reviewed search strategy, we will search key databases for clinical trials on perioperative pregabalin use in adults. The electronic searches will be supplemented by scanning the reference lists of included studies. No limits of language, country or year will be imposed. Outcomes will include pain; use of co-analgesia, particularly opioids; enhanced recovery; and drug-related harms. We will focus on the identification of surgical models and patient characteristics that have shown benefit and adverse effects from pregabalin.Two clinical experts will independently screen the studies for inclusion using eligibility criteria established a priori. Data extracted by the reviewers will then be verified. Publication bias will be assessed, as will risk of bias using the Cochrane Risk of Bias tool. Meta-analysis and meta-regression are planned if the studies are deemed statistically, methodologically and clinically homogenous. Evidence will be graded for its strength for a select number of outcomes.

DISCUSSION

We will explore the findings of perioperative clinical trials studying the use of pregabalin for acute pain. We will comment on the implications of the findings and provide further direction for the appropriate use of pregabalin in acute pain. This protocol will attempt to bridge the growing gap between clinical experience and emerging evidence, and has the potential to aid future guideline development in the perioperative use of pregabalin.

TRIAL REGISTRATION

PROSPERO registration number CRD42012002078.

Room for improvement: unmet needs in postoperative pain management

Postoperative pain treatment is an important healthcare issue. However, the management of pain in patients after surgery remains insufficient. In the present review, several key areas important for postoperative pain management are discussed. New findings about efficacy and side effects of nonopioid analgesics, such as paracetamol, NSAIDs and COX-2 inhibitors, are presented and discussed in light of acute, short-term application in the perioperative period. Second, new findings about postoperative pain management in patients with preoperative pain and chronic opioid consumption are reported. Third, feasibility of the transversus abdominal plane block as a new and promising regional anesthesia technique is discussed. Finally, potential predictors, mechanisms and preventive treatment strategies of persistent chronic pain after surgery are presented.

Anxiolytic use in the postoperative care unit

Postoperative anxiety has received less attention historically than preoperative anxiety. Recognition that anxiety occurs throughout the perioperative period has led to increased interest in identifying and treating anxiety in the postoperative period. This article outlines the causes of postoperative anxiety, how it is classified, the effects of anxiety on outcomes after surgery, and some of the clinical procedures that produce the highest levels of anxiety for patients. In addition, an attempt is made to delineate the major risk factors for developing postoperative anxiety and the classic therapeutic modalities used to reduce symptoms and treat the psychological manifestations of anxiety.

Effect of oral pregabalin premedication on post-operative pain in laparoscopic gastric bypass surgery

Background

Post-operative pain and the administration of opioids to relieve it, is considered to be one of the important issues in surgery wards. This issue is even more significant in obese patients, because of the side effects of opioids. Pregabalin is an analog of gamma aminobutyric acid (GABA) which can be effective in dealing with post-operative pain.

Objectives

This study will consider the effect of oral pregabalin in relieving the pain of obese patients after gastric bypass surgery.

Patients and Methods

In a double blind clinical trial, 60 candidates for laparoscopic gastric bypass surgery were enrolled in the study through convenience and non-random sequential sampling, into two groups; pregabalin group and control group. Inclusion criteria consisted of: morbid obesity with a body mass index (BMI) > 35, age 18–50, American Society of Anesthesiologists (ASA) status I or II, and willingness to take part in the study. Patients in the pregabalin group received 300 mg of oral pregabalin on the morning of the surgery. Post-operative pain was controlled by the patient-controlled intravenous analgesia (PCIA) method, an AutoMed infusion pump containing 20 mg of morphine and normal saline (total volume 100 cc) was administered to all patients after surgery. Patients’ level of pain were compared by considering their pain intensity on a visual analog scale (VAS), and the occurrence of nausea/vomiting from recovery, until 24 hours after surgery.

Results

A total of 60 patients were compared; 30 patients in each of the pregabalin and control groups. Both groups were similar in age and sex distribution. Mean pain intensity levels during the whole follow up were lower in the pregabalin group than in the control group, up to a maximum of 24 hours after the operation (P < 0.001). Incidence of nausea/vomiting was greater in the control group than in the pregabalin group (P < 0.001).

Conclusions

The findings of this study indicate that oral pregabalin (300 mg dose) can alleviate patients’ pain and nausea/vomiting and notably reduce adverse effects.

Managing co-occurring substance use and pain disorders

The safest pain treatment strategy for an individual at risk or recovering from addiction is a nonopioid and benzodiazepine-free approach. If an opioid treatment is necessary, the extent of the risk can be stratified by the use of a biopsychosocial assessment and opioid screening tools. Individuals at high risk should have the greatest amount of structure and monitoring. A written informed consent and treatment agreement can provide a framework for the patient and the patient’s family, as well as the clinician. The structure of treatment should specify only that one prescribing physician will write a limited supply of opioids, without refills, until the analgesic efficacy, adverse events, and goals for functional restoration can be assessed. An additional recommendation is that prescriptions should be filled at the same pharmacy with no refill by phone or opportunity for replacement because of loss, damage, or stolen medications. Additionally, random urine drug screens and PDMP reports obtained will help determine if the patient is taking other substances, as well as monitor the patient’s medication use patterns. It is important to assess for risk factors in treating chronic pain with opioids; clinicians need to have a realistic appreciation of the resources available to them and the types of patients that can be managed in their practice. Chronic pain treatment with opioids should not be undertaken in patients who are currently addicted to illicit substances or alcohol. With the support of family and friends, ideally the patient can be motivated to participate in an intensive substance abuse treatment. In patients without an immediate risk, precautionary steps should be taken when prescribing opioids. Clinicians and patients need to review the risk factors for opioid-related problems including younger age, benzodiazepine use, and comorbid conditions such as depression, anxiety, and heavy smoking. Both the provider and the patient need a personal investment in the treatment plan and protocol to increase the safety of opioid treatment. New medications and treatment monitoring are being developed to provide maximal relief for the patient while protecting the public health. The optimal ingredients for safe opioid treatment include a strong provider-patient relationship and clinician training in the assessment and treatment of addiction and pain.

Pain management in dermatologic procedures: before and after

BACKGROUND

Periprocedural analgesic therapy is an often overlooked, but critical component of ensuring adequate surgical patient care and overall satisfaction with surgical outcomes. Adequate pain management requires thorough assessment of pain and complete knowledge and understanding of the various therapeutic agents available.

OBJECTIVES

To further the knowledge and understanding of current strategies in pain management.

METHODS

A literature review was conducted through PubMed to define current pain assessment and management strategies.

RESULTS AND CONCLUSIONS

Appropriate pain assessment leads to the selection of optimal pharmacologic options for pain control in the acute postoperative setting.

Prevention of chronic pain after surgical nerve injury: amputation and thoracotomy

Although techniques for acute pain management have improved in recent years, a dramatic reduction in the incidence and severity of chronic pain following surgery has not occurred. Amputation and thoracotomy, although technically different, share the commonalities of unavoidable nerve injury and the frequent presence of persistent postsurgical neuropathic pain. The authors review the risk factors for the development of chronic pain following these surgeries and the current evidence that supports analgesic interventions. The inconclusive results from many preemptive analgesic studies may require us to reconceptualize the perioperative treatment period as a time of gradual neurologic remodeling.

Preventing Chronic Pain following Acute Pain: Risk Factors, Preventive Strategies, and their Efficacy

Chronic pain is the leading cause of disability in the United States. The transition from acute to persistent pain is thought to arise from maladaptive neuroplastic mechanisms involving three intertwined processes, peripheral sensitization, central sensitization, and descending modulation. Strategies aimed at preventing persistent pain may target such processes. Models for studying preventive strategies include persistent post-surgical pain (PPP), persistent post-trauma pain (PTP) and post-herpetic neuralgia (PHN). Such entities allow a more defined acute onset of tissue injury after which study of the long-term effects is more easily examined. In this review, we examine the pathophysiology, epidemiology, risk factors, and treatment strategies for the prevention of chronic pain using these models. Both pharmacological and interventional approaches are described, as well as a discussion of preventive strategies on the horizon.

Evaluation of efficacy of oral pregabalin in reducing postoperative pain in patients undergoing total knee arthroplasty

BACKGROUND

Optimal pain treatment with minimal side effects is essential for early mobility and recovery in patients undergoing total knee arthroplasty (TKA). We investigated the effect of pregabalin as an adjuvant for postoperative analgesia provided by opioid-based patient-controlled epidural analgesia (PCEA) in such patients.

MATERIALS AND METHODS

Forty patients undergoing unilateral primary TKA were randomly assigned to two equal groups, to receive either placebo or pregabalin 75 mg twice a day. The drug was administered orally starting before surgery and was continued for 2 days after surgery. Anesthetic technique was standardized. Postoperatively, static and dynamic pain was assessed by verbal rating score. Mean morphine consumption, PCEA usage, rescue analgesic requirement, and overall patient satisfaction were also assessed. Treatment emergent adverse drug reactions were recorded.

RESULTS

Mean morphine consumption was significantly reduced by pregabalin. Postoperative pain (both static and dynamic) and PCEA consumption too was significantly reduced in the pregabalin group during the first 48 h after surgery. This group needed fewer rescue analgesics and recorded higher overall patient satisfaction. Pregabalin-treated patients had fewer opioid-related adverse reactions like nausea, vomiting, and constipation. Dizziness was noted in two of the patients receiving pregabalin. There was no statically significant difference in the incidence of sedation in the two groups.

CONCLUSIONS

Oral pregabalin 75 mg started preoperatively is a useful adjunct to epidural analgesia following TKA. It reduces opioid consumption, improves postoperative analgesia, and yields higher patient satisfaction levels.

Acute postoperative pain management in the older patient

Acute pain management in the older adult is both challenging and rewarding. This review addresses the difficulty with assessment of pain in the older adult, variations in the pain experience of older adults, physiological differences between the young and old, changes in pharmacokinetics and pharmacodynamics with age, and useful pharmacological treatments for acute pain in older adults. It then presents a few representative cases of pain management in older adults. The goal of this review is to provide relevant information that can be used to manage acute postoperative pain in the older adult.

Why still in hospital after fast-track hip and knee arthroplasty?

BACKGROUND AND PURPOSE

Length of stay (LOS) following total hip and knee arthroplasty (THA and TKA) has been reduced to about 3 days in fast-track setups with functional discharge criteria. Earlier studies have identified patient characteristics predicting LOS, but little is known about specific reasons for being hospitalized following fast-track THA and TKA.

PATIENTS AND METHODS

To determine clinical and logistical factors that keep patients in hospital for the first postoperative 24-72 hours, we performed a cohort study of consecutive, unselected patients undergoing unilateral primary THA (n = 98) or TKA (n = 109). Median length of stay was 2 days. Patients were operated with spinal anesthesia and received multimodal analgesia with paracetamol, a COX-2 inhibitor, and gabapentin-with opioid only on request. Fulfillment of functional discharge criteria was assessed twice daily and specified reasons for not allowing discharge were registered.

RESULTS

Pain, dizziness, and general weakness were the main clinical reasons for being hospitalized at 24 and 48 hours postoperatively while nausea, vomiting, confusion, and sedation delayed discharge to a minimal extent. Waiting for blood transfusion (when needed), for start of physiotherapy, and for postoperative radiographic examination delayed discharge in one fifth of the patients.

INTERPRETATION

Future efforts to enhance recovery and reduce length of stay after THA and TKA should focus on analgesia, prevention of orthostatism, and rapid recovery of muscle function.

Pregabalin in acute and chronic pain

Pregabalin is a gamma-amino-butyric acid analog shown to be effective in several models of neuropathic pain, incisional injury, and inflammatory injury. In this review, the role of pregabalin in acute postoperative pain and in chronic pain syndromes has been discussed. Multimodal perioperative analgesia with the use of gabapentinoids has become common. Based on available evidence from randomized controlled trials and meta-analysis, the perioperative administration of pregabalin reduces opioid consumption and opioid-related adverse effects in the first 24 h following surgery. Postoperative pain intensity is however not consistently reduced by pregabalin. Adverse effects like visual disturbance, sedation, dizziness, and headache are associated with higher doses. The advantage of the perioperative use of pregabalin is so far limited to laparoscopic, gynecological, and daycare surgeries which are not very painful. The role of the perioperative administration of pregabalin in preventing chronic pain following surgery, its efficacy in more painful surgeries and surgeries done under regional anesthesia, and the optimal dosage and duration of perioperative pregabalin need to be studied. The efficacy of pregabalin in chronic pain conditions like painful diabetic neuropathy, postherpetic neuralgia, central neuropathic pain, and fibromyalgia has been demonstrated.

A randomized controlled trial to compare pregabalin with gabapentin for postoperative pain in abdominal hysterectomy

Background:

Pregabalin is a potent ligand for alpha-2-delta subunit of voltage-gated calcium channels in the central nervous system, which exhibits potent anticonvulsant, analgesic and anxiolytic activity. The pharmacological activity of pregabalin is similar to that of gabapentin and shows possible advantages. Although it shows analgesic efficacy against neuropathic pain, very limited evidence supports its postoperative analgesic efficacy. We investigated its analgesic efficacy in patients experiencing acute pain after abdominal hysterectomy and compared it with gabapentin and placebo.

Methods:

A randomized, double-blind, placebo-controlled study was conducted in 90 women undergoing abdominal hysterectomy who were anaesthetized in a standardized fashion. Patients received 300 mg pregabalin, 900 mg gabapentin or placebo, 1–2 hours prior to surgery. Postoperative analgesia was administered at visual analogue scale (VAS) ≥3. The primary outcome was analgesic consumption over 24 hours and patients were followed for pain scores, time to rescue analgesia and side effects as secondary outcomes.

Results:

The diclofenac consumption was statistically significant between pregabalin and control groups, and gabapentin and control groups; however, pregabalin and gabapentin groups were comparable. Moreover, the consumption of tramadol was statistically significant among all the groups. Patients in pregabalin and gabapentin groups had lower pain scores in the initial hour of recovery. However, pain scores were subsequently similar in all the groups. Time to first request for analgesia was longer in pregabalin group followed by gabapentin and control groups.

Conclusion:

A single dose of 300 mg pregabalin given 1–2 hours prior to surgery is superior to 900 mg gabapentin and placebo after abdominal hysterectomy. Both the drugs are better than placebo.

A systematic review of interventions to facilitate ambulatory laparoscopic cholecystectomy

OBJECTIVES

  We aimed to perform a systematic review of the literature to identify interventions that may facilitate ambulatory laparoscopic cholecystectomy (LC).

METHODS

The PubMed and CENTRAL databases were interrogated for key MeSH headings. To be eligible for systematic review, trials were required to include outcome measures of postoperative pain, nausea or vomiting and time to discharge following LC. Interventions were subsequently assessed for the level of evidence and grade of recommendation given.

RESULTS

A total of 331 trials were identified, 68 of which met the predefined study inclusion criteria. Interventions which met Level I, Grade A recommendation included the administration of 8 mg i.v. dexamethasone, preoperative administration of analgesia including the use of non-steroidal anti-inflammatory or COX II inhibitors, intraoperative use of an anti-emetic, pre-incisional use of bupivacaine, administration of intraperitoneal bupivacaine on establishment of pneumoperitoneum, and avoidance of drains.

CONCLUSIONS

  High-quality evidence describing interventions that minimize barriers to ambulatory LC exists. Further studies will be required to determine the optimal combination of these interventions.

The analgesic and antiemetic efficacy of gabapentin or ergotamine/caffeine for the treatment of postdural puncture headache

PURPOSE

We investigated the analgesic and antiemetic efficacy of gabapentin or ergotamine/caffeine (Cafergot), in addition to conservative treatment consisting of bed rest and adequate fluid intake, for the treatment of postdural puncture headache (PDPH).

METHODS

In this randomized, prospective, controlled study, gabapentin or Cafergot was administered to 42 adult patients suffering from PDPH. Patients were asked to record the severity of their headache and the number of vomiting episodes on a visual analogue scale (VAS) on days 1, 2, 3 and 4. The pain scale consisted of a 10 cm horizontal line marked from 0 (denoting no pain) to 10 (denoting worst possible imaginable pain) Emesis was scored as 0 = no emetic symptoms, 1 = nausea or 2 = vomiting.

RESULTS

Demographic and anesthetic variables were similar between the groups. Gabapentin group had less pain, nausea and vomiting compared to the Cafergot group. No patients withdrew, gabapentin and Cafergot were well tolerated, and adverse events (somnolence, dizziness, tremor, and ataxia) did not occur.

CONCLUSIONS

Gabapentin significantly reduced pain, nausea and vomiting compared to Cafergot in patients with PDPH. Lastly, we hypothesize that the gabaergic action of gabapentin, perhaps combined with other mechanisms, such as calcium channel blockade, may be responsible for its remarkable effects on PDPH.

Evidence-based management of postoperative pain in adults undergoing open inguinal hernia surgery

Background

Open inguinal hernia repair is associated with moderate postoperative pain, but optimal analgesia remains controversial. The aim of this systematic review was to evaluate the available literature on the management of pain after open hernia surgery.

Methods

Randomized studies, in English, published between January 1966 and March 2009, assessing analgesic and anaesthetic interventions in adult open hernia surgery, and reporting pain scores, were retrieved from the Embase and MEDLINE databases. In addition to published evidence, clinical practice was taken into account to ensure that the recommendations had clinical validity.

Results

Of the 334 randomized studies identified, 79 were included. Quantitative analysis suggested that regional anaesthesia was superior to general anaesthesia for reducing postoperative pain. Spinal anaesthesia was associated with a higher incidence of urinary retention and increased time to home-readiness compared with regional anaesthesia.

Conclusion

Field block with, or without wound infiltration, either as a sole anaesthetic/analgesic technique or as an adjunct to general anaesthesia, is recommended to reduce postoperative pain. Continuous local anaesthetic infusion of a surgical wound provides a longer duration of analgesia. Conventional non-steroidal anti-inflammatory drugs or cyclo-oxygenase 2-selective inhibitors in combination with paracetamol, administered in time to provide sufficient analgesia in the early recovery phase, are optimal. In addition, weak opioids are recommended for moderate pain, and strong opioids for severe pain, on request.

An expert opinion on postoperative pain management, with special reference to new developments

IMPORTANCE OF THE FIELD

Recently, much attention has been directed towards the effect of opioid-sparing strategies on postoperative morbidity and hospitalization, and on different nociceptive mechanisms involved in various postoperative pain states and surgical procedures. This has resulted in an increased interest in secondary, or adjunct, analgesics and procedure-specific analgesic methods.

AREAS COVERED IN THIS REVIEW

The present paper aims to review and discuss recent developments within the field of various adjunct, systemic analgesics and local/regional anesthetic methods for management of postoperative pain, based on evidence from randomized, clinical trials published within the last 5 years.

WHAT THE READER WILL GAIN

The reader will gain insight into the current role of pregabalin, glucocorticoids and systemic lidocaine for the management of postoperative pain. In addition, the current status of local infiltration analgesia for hip and knee arthroplasty, transversus abdominis plane block for abdominal operations, and the analgesic effect of wound instillation of capsaicin are reviewed.

TAKE HOME MESSAGE

The evidence of a substantial analgesic effect of pregabalin on acute postoperative pain is questionable, and more convincing evidence of the role of glucocorticoids and systemic lidocaine is needed before they should be recommended as analgesics in daily clinical practice. Local infiltration analgesia after hip and knee arthroplasty, transversus abdominis plane block after abdominal operations and local application of capsaicin lend some promise, but there is still a lack of well-performed RCTs to draw any firm conclusions. Procedure-specific analgesic combinations within well-defined rehabilitation paradigms should be explored further to reduce adverse effects associated with the use of conventional analgesic treatment protocols, and to improve postoperative outcome.

Morphine use in cancer surgery

Morphine is the core of perioperative pain management. However, when it comes to cancer surgery the possibility that this drug might affect tumor recurrence and metastasis has raised concerns. The results of two recent retrospective clinical trials indicated that regional anesthesia/analgesia might be beneficial in prostate and breast cancer surgery. It was proposed that morphine could be responsible for the higher recurrence and mortality rate observed in the general anesthesia/opioid analgesia groups. Nevertheless, the results of several other retrospective studies and one randomized prospective trial failed to confirm any advantage for regional anesthesia/analgesia over general anesthesia and opioid analgesia. Moreover laboratory data on the effect of morphine on cancer are contradictory, ranging from tumor-promoting to anti-tumor effects. Considering that surgical stress and pain promote the recurrence and spread of cancer, choosing a proper analgesic strategy is of high significance. Although the question of whether morphine causes any harm to cancer patients remains unanswered, alternative analgesic regimens could be used concomitant to or instead of morphine to limit its potential adverse effects.

High-volume infiltration analgesia in bilateral hip arthroplasty. A randomized, double-blind placebo-controlled trial

BACKGROUND AND PURPOSE

High-volume infiltration analgesia may be effective in postoperative pain management after hip arthroplasty but methodological problems prevent exact interpretation of previous studies.

METHODS

In a randomized, double-blind placebo-controlled trial in 12 patients undergoing bilateral total hip arthroplasty (THA) in a fast-track setting, saline or high-volume (170 mL) ropivacaine (0.2%) with epinephrine (1:100,000) was administered to the wound intraoperatively along with supplementary postoperative injections via an intraarticular epidural catheter. Oral analgesia was instituted preoperatively with a multimodal regimen (gabapentin, celecoxib, and acetaminophen). Pain was assessed repeatedly for 48 hours postoperatively, at rest and with 45° hip flexion.

RESULTS

Pain scores were low and similar between ropivacaine and saline administration. Median hospital stay was 4 (range 2-7) days. Interpretation Intraoperative high-volume infiltration with 0.2% ropivacaine with repeated intraarticular injections postoperatively may not give a clinically relevant analgesic effect in THA when combined with a multimodal oral analgesic regimen with gabapentin, celecoxib, and acetaminophen.