Pharmacogenomics, concepts for the future of perioperative medicine and pain management: A review.

Pharmacogenomics is the study of how genetic differences between individuals affect pharmacokinetics and pharmacodynamics. These differences are apparent to clinicians when taking into account the wide range of responses to medications given in clinical practice. A review of literature involving pharmacogenomics and pain management was performed. The implementation of preoperative pharmacogenomics will allow us to better care for our patients by delivering personalized, safer medicine. This review describes the current state of pharmacogenomics as it relates to many aspects of clinical practice and how clinicians can use these tools to improve patient outcomes.

Upper extremity regional anesthesia techniques: A comprehensive review for clinical anesthesiologists.

Surgeries and chronic pain states of the upper extremity are quite common and pose unique challenges for the clinical anesthesiology and pain specialists. Most innervation of the upper extremity involves the brachial plexus. The four most common brachial plexus blocks performed in clinical setting include the interscalene, supraclavicular, infraclavicular, and axillary brachial plexus blocks. These blocks are most commonly performed with the use of ultrasound-guided techniques, whereby analgesia is achieved by anesthetizing the brachial plexus at different levels such as the roots, divisions, cords, and branches. Additional regional anesthetic techniques for upper extremity surgery include wrist, intercostobrachial, and digital nerve blocks, which are most frequently performed using landmark anatomical techniques. This review provides a comprehensive summary of each of these blocks including anatomy, best practice techniques, and potential complications.

Fascia iliaca block, history, technique, and efficacy in clinical practice.

The facsia iliaca block (FIB) is a relatively new regional technique where local anesthetic is delivered within the fascia iliaca region. Indications for a FIB include surgical anesthesia to the lower extremity after knee, femoral shaft, hip surgery, management of cancer pain or pain secondary to inflammatory conditions of the lumbar plexus, as well as treatment of acute pain in the setting of trauma, fracture, or burns. The FIB may be performed using either a loss of resistance technique or an ultrasound (US)-guided technique; however, the use of US has become commonplace and resulted in improved femoral nerve and obturator nerve motor blocks. The main targets of the FIB are the predominant nerves contained in the fascia iliaca compartment (FIC), namely the femoral nerve and the lateral femoral cutaneous nerve. The FIB US guided technique is beneficial to patients and the possibility to perform FIB should be discussed and coordinated with surgical staff appropriately, considering its superiority to general or epidural anesthesia.

Truncal regional nerve blocks in clinical anesthesia practice.

Regional anesthetic techniques are important components of successful multimodal analgesic strategies. When used successfully, truncal nerve blocks of the chest wall, abdomen, and, paraneuraxial nerves, in combination with other analgesic modalities, may offer similar analgesic efficacy as neuraxial techniques, which are associated with a greater risk profile. Moreover, in comparison to neuraxial techniques, truncal nerve blocks are relatively simple to perform and technically straightforward to learn. The transversus abdominus plane (TAP) block is often incorporated into the multimodal analgesia regimen for surgical patients undergoing various abdominal and gynecological procedures. Rectus sheath blocks (RSB) were originally introduced to help relax the anterior abdominal wall during surgery and as an adjunct pain therapy. With the advancement of technology and the development of ultrasound guided techniques, RSB now have a more ubiquitous role and have been shown to decrease postoperative pain and opioid consumption. Different variations of the quadratus lumborum block may provide visceral and sensory analgesic coverage. Moreover, truncal blocks, including ilioinguinal, iliohypogastric, pectoralis nerve (PECS) blocks, serratus anterior, intercostal, and erector spinae plane blocks, have gained routine clinical use for various surgeries. In this review, we discuss the techniques, anatomy, indications, complications, and benefits of truncal nerve blocks commonly used in clinical practice.

Potential opioid-related adverse events following spine surgery in elderly patients.

OBJECTIVE: Understanding the clinical and economic impact of opioid-related adverse drug events (ORADEs) within spine surgery may guide both the clinician's and hospital administration's approach to treating perioperative pain, thus improving patient care and reducing hospital costs. The objective of this analysis is to understand how potential ORADEs after spine surgery in elderly patients affect length of stay, hospital revenue and their association with comorbid conditions. PATIENTS AND METHODS: We conducted a retrospective study utilizing the Center for Medicare/Medicaid Services Administrative Database to analyze Medicare discharges between April 2016 and March 2017 involving 14 spine surgery DRGs for major spine procedures in order to identify potential ORADEs. An analysis was conducted using this database to identify the incidence of potential ORADEs as well as their impact on mean hospital length of stay and hospital revenue. RESULTS: There were 177,432 discharges during the study period. The ORADE rate in patients undergoing spine surgery was 13.9% (24,642/177,432). The mean length of stay (LOS) for discharges with an ORADE was 3.13 days longer than without an ORADE (6.29 days with an ORADE vs 3.16 days without an ORADE). The adverse post-operative outcomes most strongly associated with potential ORADEs included shock, pneumonia, and septicemia. The mean hospital revenue per day with an ORADE was $3,076 less than without an ORADE ($7,263 with an ORADE vs $10,339 without an ORADE). CONCLUSION: Potential ORADEs in spine surgery in elderly patients are common and are associated with longer hospitalizations and decreased hospital revenue. Perioperative pain management strategies that reduce ORADEs may improve patient care and increase hospital revenue.

Regional Catheters for Outpatient Surgery-a Comprehensive Review.

PURPOSE OF REVIEW: This review summarizes and discusses the history of continuous catheter blockade (CCB), its current applications, clinical considerations, economic benefits, potential complications, patient education, and best practice techniques. RECENT FINDINGS: Regional catheters for outpatient surgery have greatly impacted acute post-operative pain management and recovery. Prior to development, options for acute pain management were limited to the use of opioid pain medications, NSAIDS, neuropathic agents, and the like as local anesthetic duration of action is limited to 4-8 h. Moreover, delivery of opioids post-operatively has been associated with respiratory and central nervous depression, development of opioid use disorder, and many other potential adverse effects. CCB allows for faster recovery time, decreased rates of opioid abuse, and better pain control in patients post-operatively. Outpatient surgical settings continue to focus on efficiency, quality, and safety, including strategies to prevent post-operative nausea, vomiting, and pain. Regional catheters are a valuable tool and help achieve all of the well-established endpoints of enhanced recovery after surgery (ERAS). CCB is growing in popularity with wide indications for a variety of surgeries, and has demonstrated improved patient satisfaction, outcomes, and reductions in many unwanted adverse effects in the outpatient setting.

The Role of Complementary and Alternative Medicine Treatments in Fibromyalgia: a Comprehensive Review.

PURPOSE OF REVIEW: Fibromyalgia is a complex chronic pain syndrome that can have debilitating consequences for affected patients. When compared to the general population, patients with fibromyalgia experience lowered mechanical and thermal pain thresholds, altered temporal summation of painful stimuli, and higher than normal pain ratings for known noxious stimuli. RECENT FINDINGS: There is no definitive cure for fibromyalgia and treatment primarily focuses on both symptom management and improving patient quality of life. This treatment strategy involves a comprehensive multidisciplinary approach consisting of lifestyle modifications, pharmacologic measures, and other complementary approaches including but not limited to acupuncture, yoga, tai chi, and meditation. This manuscript will discuss the diagnosis and treatment of fibromyalgia, as well as complementary and alternative therapies that should be considered by healthcare providers.

Responsible, Safe, and Effective Use of Antithrombotics and Anticoagulants in Patients Undergoing Interventional Techniques: American Society of Interventional Pain Physicians (ASIPP) Guidelines.

BACKGROUND: Interventional pain management involves diagnosis and treatment of chronic pain. This specialty utilizes minimally invasive procedures to target therapeutics to the central nervous system and the spinal column. A subset of patients encountered in interventional pain are medicated using anticoagulant or antithrombotic drugs to mitigate thrombosis risk. Since these drugs target the clotting system, bleeding risk is a consideration accompanying interventional procedures. Importantly, discontinuation of anticoagulant or antithrombotic drugs exposes underlying thrombosis risk, which can lead to significant morbidity and mortality especially in those with coronary artery or cerebrovascular disease. This review summarizes the literature and provides guidelines based on best evidence for patients receiving anti-clotting therapy during interventional pain procedures. STUDY DESIGN: Best evidence synthesis. OBJECTIVE: To provide a current and concise appraisal of the literature regarding an assessment of the bleeding risk during interventional techniques for patients taking anticoagulant and/or antithrombotic medications. METHODS: A review of the available literature published on bleeding risk during interventional pain procedures, practice patterns and perioperative management of anticoagulant and antithrombotic therapy was conducted. Data sources included relevant literature identified through searches of EMBASE and PubMed from 1966 through August 2018 and manual searches of the bibliographies of known primary and review articles. RESULTS: 1. There is good evidence for risk stratification by categorizing multiple interventional techniques into low-risk, moderate-risk, and high-risk. Also, their risk should be upgraded based on other risk factors.2. There is good evidence for the risk of thromboembolic events in patients who interrupt antithrombotic therapy. 3. There is good evidence supporting discontinuation of low dose aspirin for high risk and moderate risk procedures for at least 3 days, and there is moderate evidence that these may be continued for low risk or some intermediate risk procedures.4. There is good evidence that discontinuation of anticoagulant therapy with warfarin, heparin, dabigatran (Pradaxa®), argatroban (Acova®), bivalirudin (Angiomax®), lepirudin (Refludan®), desirudin (Iprivask®), hirudin, apixaban (Eliquis®), rivaroxaban (Xarelto®), edoxaban (Savaysa®, Lixiana®), Betrixaban(Bevyxxa®), fondaparinux (Arixtra®) prior to interventional techniques with individual consideration of pharmacokinetics and pharmacodynamics of the drugs and individual risk factors increases safety.5. There is good evidence that diagnosis of epidural hematoma is based on severe pain at the site of the injection, rapid neurological deterioration, and MRI with surgical decompression with progressive neurological dysfunction to avoid neurological sequelae.6. There is good evidence that if thromboembolic risk is high, low molecular weight heparin bridge therapy can be instituted during cessation of the anticoagulant, and the low molecular weight heparin can be discontinued 24 hours before the pain procedure.7. There is fair evidence that the risk of thromboembolic events is higher than that of epidural hematoma formation with the interruption of antiplatelet therapy preceding interventional techniques, though both risks are significant.8. There is fair evidence that multiple variables including anatomic pathology with spinal stenosis and ankylosing spondylitis; high risk procedures and moderate risk procedures combined with anatomic risk factors; bleeding observed during the procedure, and multiple attempts during the procedures increase the risk for bleeding complications and epidural hematoma.9. There is fair evidence that discontinuation of phosphodiesterase inhibitors is optional (dipyridamole [Persantine], cilostazol [Pletal]. However, there is also fair evidence to discontinue Aggrenox [dipyridamole plus aspirin]) 3 days prior to undergoing interventional techniques of moderate and high risk. 10. There is fair evidence to make shared decision making between the patient and the treating physicians with the treating physician and to consider all the appropriate risks associated with continuation or discontinuation of antithrombotic or anticoagulant therapy.11. There is fair evidence that if thromboembolic risk is high antithrombotic therapy may be resumed 12 hours after the interventional procedure is performed.12. There is limited evidence that discontinuation of antiplatelet therapy (clopidogrel [Plavix®], ticlopidine [Ticlid®], Ticagrelor [Brilinta®] and prasugrel [Effient®]) avoids complications of significant bleeding and epidural hematomas.13. There is very limited evidence supporting the continuation or discontinuation of most NSAIDs, excluding aspirin, for 1 to 2 days and some 4 to 10 days, since these are utilized for pain management without cardiac or cerebral protective effect. LIMITATIONS: The continued paucity of the literature with discordant recommendations. CONCLUSION: Based on the survey of current literature, and published clinical guidelines, recommendations for patients presenting with ongoing antithrombotic therapy prior to interventional techniques are variable, and are based on comprehensive analysis of each patient and the risk-benefit analysis of intervention. KEY WORDS: Perioperative bleeding, bleeding risk, practice patterns, anticoagulant therapy, antithrombotic therapy, interventional techniques, safety precautions, pain.

Opioid addiction, diversion, and abuse in chronic and cancer pain.

PURPOSE OF REVIEW: The primary cause of overdose death in the United States is related to pharmaceutical opioids. A few particular populations that struggle with adverse outcomes related to opioid abuse are those in palliative care, those with chronic pain, and those receiving pain treatments secondary to cancer or chemotherapy. RECENT FINDINGS: There have been massive efforts to decrease the use of opioid abuse in patient care in a gestalt manner, but palliative care provides unique challenges in applying these reduction tactics used by other specialties. SUMMARY: We explore behavioral interventions, provider education, alternative pain management techniques, postmarketing surveillance, and abuse-deterrent formulas as emerging methods to counteract opioid abuse in these populations.