ABSTRACT
PURPOSE OF REVIEW: The goal of this review is to summarize updates to the broad array of complementary therapies available for cancer pain. This paper will serve as a reference for clinicians managing pain in cancer patients. RECENT FINDINGS: Patients are embracing integrative therapies in growing numbers; clinicians must be prepared to incorporate these therapies into patients' existing treatment regimens. This requires knowledge regarding risks, benefits, and potential interactions with existing cancer therapies. Integrative cancer pain management strategies have shown promise, with several proven effective for the management of cancer pain. Energy therapies, including acupuncture, and biologicals and nutraceuticals including overall diet and vitamin D, have the highest level of evidence for efficacy. The remaining therapies discussed in this chapter may be beneficial for patients on a case-by-case basis; risks and benefits of each individual therapy as described in the text must be further assessed in future rigorous trials to further clarify the role of these complementary therapies in cancer pain management.
Subject(s)
Cancer Pain , Complementary Therapies , Pain Management , Humans , Cancer Pain/therapy , Pain Management/methods , Complementary Therapies/methods , Neoplasms/complications , Neoplasms/therapy , Integrative Medicine/methodsABSTRACT
Early allograft dysfunction (EAD) is a functional hepatic insufficiency within a week of orthotopic liver transplantation (OLT) and is associated with morbidity and mortality. The etiology of EAD is multifactorial and largely driven by ischemia reperfusion injury (IRI), a phenomenon characterized by oxygen scarcity followed by paradoxical oxidative stress and inflammation. With the expanded use of marginal allografts more susceptible to IRI, the incidence of EAD may be increasing. This necessitates an in-depth understanding of the innate molecular mechanisms underlying EAD and interventions to mitigate its impact. Our central hypothesis is peri-reperfusion hyperoxemia and immune dysregulation exacerbate IRI and increase the risk of EAD. We will perform a pilot prospective single-center observational cohort study of 40 patients. The aims are to determine (1) the association between peri-reperfusion hyperoxemia and EAD and (2) whether peri-reperfusion perturbed cytokine, protein, and hypoxia inducible factor-1 alpha (HIF-1α) levels correlate with EAD after OLT. Inclusion criteria include age ≥ 18 years, liver failure, and donation after brain or circulatory death. Exclusion criteria include living donor donation, repeat OLT within a week of transplantation, multiple organ transplantation, and pregnancy. Partial pressure of arterial oxygen (PaO2) as the study measure allows for the examination of oxygen exposure within the confines of existing variability in anesthesiologist-administered fraction of inspired oxygen (FiO2) and the inclusion of patients with intrapulmonary shunting. The Olthoff et al. definition of EAD is the primary outcome. Secondary outcomes include postoperative acute kidney injury, pulmonary and biliary complications, surgical wound dehiscence and infection, and mortality. The goal of this study protocol is to identify EAD contributors that could be targeted to attenuate its impact and improve OLT outcomes. If validated, peri-reperfusion hyperoxemia and immune perturbations could be targeted via FiO2 titration to a goal PaO2 and/or administration of an immunomodulatory agent by the anesthesiologist intraoperatively.
Subject(s)
Liver Failure , Liver Transplantation , Humans , Adolescent , Liver Transplantation/adverse effects , Prospective Studies , Risk Factors , Graft Survival , Liver/metabolism , Cohort Studies , Allografts , Reperfusion , Oxygen/metabolism , Observational Studies as TopicABSTRACT
Fibromyalgia is a chronic pain syndrome that presents with a constellation of broad symptoms, including decreased physical function, fatigue, cognitive disturbances, and other somatic complaints. Available therapies are often insufficient in treating symptoms, with inadequate pain control commonly leading to opioid usage for attempted management. Cranial electrical stimulation (CES) is a promising non-pharmacologic treatment option for pain conditions that uses pulsed electrical current stimulation to modify brain function via transcutaneous electrodes. These neural mechanisms and the applications of CES in fibromyalgia symptom relief require further exploration. A total of 50 participants from the Atlanta Veterans Affairs Healthcare System (VAHCS) diagnosed with fibromyalgia were enrolled and then block-randomized into either a placebo plus standard therapy or active CES plus standard therapy group. Baseline assessments were obtained prior to the start of treatment. Both interventions occurred over 12 weeks, and participants were assessed at 6 weeks and 12 weeks after treatment initiation. The primary outcome investigated whether pain and functional improvements occur with the application of CES. Additionally, baseline and follow-up resting state functional connectivity magnetic resonance imaging (rs-fcMRI) were obtained at the 6-week and 12-week time points to assess for clinical applications of neural connectivity biomarkers and the underlying neural associations related to treatment effects. This is a randomized, placebo-controlled trial to determine the efficacy of CES for improving pain and function in fibromyalgia and further develop rs-fcMRI as a clinical tool to assess the neural correlates and mechanisms of chronic pain and analgesic response.
Subject(s)
Chronic Pain , Fibromyalgia , Humans , Fibromyalgia/therapy , Chronic Pain/diagnostic imaging , Chronic Pain/therapy , Brain/diagnostic imaging , Electric Stimulation , Biomarkers , NeuroimagingABSTRACT
Jacobsen SM, Moore T, Douglas A, Lester D, Johnson AL, Vassar M. Discontinuation and nonpublication analysis of chronic pain randomized controlled trials. PAIN Rep 2023;8:e1069.
ABSTRACT
Objective: To evaluate changes in cortical thickness and right posterior insula (r-pIns) gamma-aminobutyric acid (GABA) concentrations in veterans with fibromyalgia treated with auricular percutaneous electric nerve field stimulation (PENFS). Materials & methods: This was a randomized, controlled, open label investigation conducted in a government hospital. Twenty-one veterans with fibromyalgia were randomized to receive either standard therapy (ST; i.e., 4 weekly visits with a pain practitioner) or ST with auricular PENFS (STâ¯+â¯PENFS). Neuroimaging data was collected at baseline (i.e. before the first treatment session) and again within 2â¯weeks post-treatment.â Clinical pain and physical function were also assessed at these timepoints. Single-voxel magnetic resonance spectroscopy was carried out in r-pIns to assess changes in r-pIns GABA concentrations and high-resolution T1-weighted images were collected to assess changes in regional gray matter volume using cortical thickness. Results: Both the STâ¯+â¯PENFS and ST groups reported a decrease in pain with treatment. Volumetric: Cortical thickness significantly decreased in the left middle posterior cingulate (pâ¯=â¯0.018) and increased in the left cuneus (pâ¯=â¯0.014) following STâ¯+â¯PENFS treatment. These findings were significant following FDR correction for multiple comparisons. ST group right hemisphere insula cortical thickness increased post-treatment and was significantly (pâ¯=â¯0.02) inversely correlated with pain scores. STâ¯+â¯PENFS group right hemisphere posterior dorsal cingulate size significantly (pâ¯=â¯0.044) positively correlated with pain scores. GABA: There were no significant correlations with GABA, though a trend was noted towards increased GABA following treatment in both groups (pâ¯=â¯0.083) using a linear mixed effects model. Conclusions: Results suggest a novel effect of PENFS reflected by differential volumetric changes compared to ST. The changes in GABA that occur in both groups are more likely related to ST. Insular GABA and cortical thickness in key regions of interest may be developed as potential biomarkers for evaluating chronic pain pathology and treatment outcomes.
ABSTRACT
BACKGROUND: Posttraumatic stress disorder (PTSD) is a highly disabling condition associated with alterations in multiple neurobiological systems, including increases in inflammatory and sympathetic function, responsible for maintenance of symptoms. Treatment options including medications and psychotherapies have limitations. We previously showed that transcutaneous Vagus Nerve Stimulation (tcVNS) blocks inflammatory (interleukin (IL)-6) responses to stress in PTSD. The purpose of this study was to assess the effects of tcVNS on PTSD symptoms and inflammatory responses to stress. METHODS: Twenty patients with PTSD were randomized to double blind active tcVNS (N=9) or sham (N=11) stimulation in conjunction with exposure to personalized traumatic scripts immediately followed by active or sham tcVNS and measurement of IL-6 and other biomarkers of inflammation. Patients then self administered active or sham tcVNS twice daily for three months. PTSD symptoms were measured with the PTSD Checklist (PCL) and the Clinician Administered PTSD Scale (CAPS), clinical improvement with the Clinical Global Index (CGI) and anxiety with the Hamilton Anxiety Scale (Ham-A) at baseline and one-month intervals followed by a repeat of measurement of biomarkers with traumatic scripts. After three months patients self treated with twice daily open label active tcVNS for another three months followed by assessment with the CGI. RESULTS: Traumatic scripts increased IL-6 in PTSD patients, an effect that was blocked by tcVNS (p<.05). Active tcVNS treatment for three months resulted in a 31% greater reduction in PTSD symptoms compared to sham treatment as measured by the PCL (p=0.013) as well as hyperarousal symptoms and somatic anxiety measured with the Ham-A p<0.05). IL-6 increased from baseline in sham but not tcVNS. Open label tcVNS resulted in improvements measured with the CGI compared to the sham treatment period p<0.05). CONCLUSIONS: These preliminary results suggest that tcVNS reduces inflammatory responses to stress, which may in part underlie beneficial effects on PTSD symptoms.
ABSTRACT
Integrative medicine is an approach to medical care that embraces all effective therapies including complementary treatments such as acupuncture and hypnosis. There is growing use of complementary therapies in the cancer patient population, making it important that health care providers be aware of both the risks and benefits of treatments that lie outside of the traditional allopathic medicine paradigm. This chapter will explore some of the most common and well-investigated complementary therapies for the treatment and prevention of cancer-related pain. This will include discussions of: acupuncture, dietary supplements, massage, guided imagery and cryotherapy among others. The goal of this is to provide a framework for discussions between medical providers and their patients to ensure safety, discussion of all available treatments, and to facilitate open lines of communication.
Subject(s)
Acupuncture Therapy , Cancer Pain , Complementary Therapies , Integrative Medicine , Neoplasms , Cancer Pain/therapy , Humans , Massage , Neoplasms/complications , Neoplasms/therapyABSTRACT
Erythropoietin (EPO) is an exciting neurotherapeutic option. Despite its potential, concerns exist regarding the potential for thrombosis and adverse events with EPO administration in normonemic adults. Systematic review of literature using PRISMA guidelines to examine the application and risks of EPO as a treatment option for neuroprotection in normonemic adults. Independent, systematic searches were performed in July 2019. PubMed (1960-2019) and the Cochrane Controlled Trials Register (1960-2019) were screened. Search terms included erythropoietin, neuroprotection, and humans. The PubMed search resulted in the following search strategy: ("erythropoietin" [MeSH Terms] OR "erythropoietin" [All Fields] OR "epoetin alfa" [MeSH Terms] OR ("epoetin" [All Fields] AND "alfa" [All Fields]) OR "epoetin alfa" [All Fields]) AND ("neuroprotection" [MeSH Terms] OR "neuroprotection" [All Fields]) AND "humans" [MeSH Terms]. PubMed, Cochrane Controlled Trials Register, and articles based on prior searches yielded 388 citations. 50 studies were included, comprising of 4351 patients. There were 13 studies that noted adverse effects from EPO. Three attributed serious adverse effects to EPO and complications were statistically significant. Two of these studies related the adverse events to the co-administration of EPO with tPA. Minor adverse effects associated with the EPO group included nausea, pyrexia, headache, generalized weakness and superficial phlebitis. Most published studies focus on spinal cord injury, peri-surgical outcomes and central effects of EPO. We found no studies to date evaluating the role of EPO in post-operative pain. Future trials could evaluate this application in persistent post-surgical pain and in the peri-operative period.
Subject(s)
Erythropoietin/therapeutic use , Neuroprotection/drug effects , Neuroprotective Agents/therapeutic use , Central Nervous System Diseases/drug therapy , Erythropoietin/adverse effects , Humans , Neuroprotective Agents/adverse effects , Optic Neuritis/drug therapy , Peripheral Nervous System Diseases/drug therapyABSTRACT
OBJECTIVE: To evaluate the feasibility of recruitment, preliminary efficacy, and acceptability of auricular percutaneous electrical nerve field stimulation (PENFS) for the treatment of fibromyalgia in veterans, using neuroimaging as an outcome measure and a biomarker of treatment response. DESIGN: Randomized, controlled, single-blind. SETTING: Government hospital. SUBJECTS: Twenty-one veterans with fibromyalgia were randomized to standard therapy (ST) control or ST with auricular PENFS treatment. METHODS: Participants received weekly visits with a pain practitioner over 4 weeks. The PENFS group received reapplication of PENFS at each weekly visit. Resting-state functional connectivity magnetic resonance imaging (rs-fcMRI) data were collected within 2 weeks prior to initiating treatment and 2 weeks following the final treatment. Analysis of rs-fcMRI used a right posterior insula seed. Pain and function were assessed at baseline and at 2, 6, and 12 weeks post-treatment. RESULTS: At 12 weeks post-treatment, there was a nonsignificant trend toward improved pain scores and significant improvements in pain interference with sleep among the PENFS treatment group as compared with the ST controls. Neuroimaging data displayed increased connectivity to areas of the cerebellum and executive control networks in the PENFS group as compared with the ST control group following treatment. CONCLUSIONS: There was a trend toward improved pain and function among veterans with fibromyalgia in the ST + PENFS group as compared with the ST control group. Pain and functional outcomes correlated with altered rs-fcMRI network connectivity. Neuroimaging results differed between groups, suggesting an alternative underlying mechanism for PENFS analgesia.
Subject(s)
Fibromyalgia , Feasibility Studies , Fibromyalgia/diagnostic imaging , Fibromyalgia/therapy , Humans , Magnetic Resonance Imaging , Neuroimaging , Single-Blind MethodABSTRACT
Stellate ganglion block (SGB) is believed to modify the pathologic sympathetic pain response and has been commonly used to treat complex regional pain syndrome. We report successful treatment of cancer-related facial pain with SGB in three patients, suggesting a possible sympathetic pain-related mechanism. All patients exhibited clinically significant improvement of pain 12 weeks following the procedure. SGB should be considered a palliative pain treatment option in cancer-related facial pain.
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This chapter explores therapeutic targets and the anti-inflammatory nature of some naturally- occurring compounds and the current or potential use of these compounds in the treatment of chronic inflammatory pain states. We will review the mechanisms of chronic inflammatory pain, the molecular targets of selected natural compounds in inhibiting inflammatory pain, and the traditional and current approaches to treating pain using these compounds. Previous research on experimental as well as clinical pain will be summarized from in vitro to animal and human models. Potential areas for further research will also be discussed.
Subject(s)
Analgesics/pharmacology , Anti-Inflammatory Agents/pharmacology , Biological Products/pharmacology , Inflammation/drug therapy , Pain/drug therapy , Analgesics/therapeutic use , Animals , Anti-Inflammatory Agents/therapeutic use , Biological Products/therapeutic use , Disease Models, Animal , Drug Evaluation, Preclinical , Humans , Inflammation/complications , NF-kappa B/antagonists & inhibitors , NF-kappa B/metabolism , Pain/etiology , Prostaglandin-Endoperoxide Synthases/metabolism , Receptors, GABA/metabolism , Receptors, N-Methyl-D-Aspartate/antagonists & inhibitors , Receptors, N-Methyl-D-Aspartate/metabolism , Signal Transduction/drug effects , Transient Receptor Potential Channels/antagonists & inhibitors , Transient Receptor Potential Channels/metabolism , Treatment OutcomeABSTRACT
BACKGROUND: Fibromyalgia is a chronic pain state that includes widespread musculoskeletal pain, fatigue, psychiatric symptoms, cognitive and sleep disturbances, and multiple somatic symptoms. Current therapies are often insufficient or come with significant risks, and while there is an increasing demand for non-pharmacologic and especially non-opioid pain management such as that offered through complementary and alternative medicine therapies, there is currently insufficient evidence to recommend these therapies. Percutaneous electrical neural stimulation (PENS) is an evidence-based treatment option for pain conditions that involves electrical current stimulation through needles inserted into the skin. Percutaneous electrical neural field stimulation (PENFS) of the auricle is similar to PENS, but instead of targeting a single neurovascular bundle, PENFS stimulates the entire ear, covering all auricular branches of the cranial nerves, including the vagus nerve. The neural mechanisms of PENFS for fibromyalgia symptom relief are unknown. OBJECTIVE: We hypothesize that PENFS treatment will decrease functional brain connectivity between the default mode network (DMN) and right posterior insula in fibromyalgia patients. We expect that the decrease in functional connectivity between the DMN and insula will correlate with patient-reported analgesic improvements as indicated by the Defense and Veterans Pain Rating Scale (DVPRS) and will be anti-correlated with patient-reported analgesic medication consumption. Exploratory analyses will be performed for further hypothesis generation. METHODS: A total of 20 adults from the Atlanta Veterans Affairs Medical Center diagnosed with fibromyalgia will be randomized into 2 groups: 10 subjects to a control (standard therapy) group and 10 subjects to a PENFS treatment group. The pragmatic, standard therapy group will include pharmacologic treatments such as anticonvulsants, non-steroidal anti-inflammatory drugs, topical agents and physical therapy individualized to patient comorbidities and preferences, prescribed by a pain management practitioner. The PENFS group will include the above therapies in addition to the PENFS treatments. The PENFS subject group will have the Neuro-Stim System placed on the ear for 5 days then removed and replaced once per week for 4 weeks. The primary outcome will be resting functional magnetic resonance imaging connectivity between DMN and insula, which will also be correlated with pain relief and functional improvements. This connectivity will be analyzed utilizing functional connectivity magnetic resonance imaging (fcMRI) and will be compared with patient-reported analgesic improvements as indicated by the DVPRS and patient-reported analgesic medication consumption. Pain and function will be further evaluated using Patient-Reported Outcomes Measurement Information System measures and measures describing a person's functional status from Activity and Participation section of the International Classification of Functioning Disability and Health. RESULTS: This trial has been funded by the Veterans Health Administration Program Office. This study attained approval by the Emory University/Veterans Affairs (VA) institutional review board and VA Research & Development committee. Institutional review board expedited approval was granted on 2/7/17 (IRB00092224). The study start date is 6/1/17 and estimated completion date is 5/31/20. The recruitment started in June 2017. CONCLUSIONS: This is a feasibility study that is meant to demonstrate the practicality of using fcMRI to study the neural correlates of PENFS outcomes and provide information regarding power calculations in order to design and execute a larger randomized controlled clinical trial to determine the efficacy of PENFS for improving pain and function. TRIAL REGISTRATION: ClinicalTrials.gov NCT03008837; https://clinicaltrials.gov/ct2/show/NCT03008837 (Archived by WebCite at http://www.webcitation.org/6wrY3NmaQ).
ABSTRACT
Background: Fibromyalgia and complex regional pain syndrome (CRPS) are both chronic pain syndromes with pathophysiologic mechanisms related to autonomic nervous system dysregulation and central sensitization. Both syndromes are considered difficult to treat with conventional pain therapies. Case presentations: Here we describe a female veteran with fibromyalgia and a male veteran with CRPS, both of whom failed multiple pharmacologic, physical and psychological therapies for pain, but responded to percutaneous electrical neural field stimulation (PENFS) targeted at the auricular branches of the cranial nerves. Discussion: While PENFS applied to the body has been previously described for treatment of localized pain, PENFS effects on cranial nerve branches of the ear is not well-known, particularly when used for regional and full-body pain syndromes such as those described here. PENFS of the ear is a minimally-invasive, non-pharmacologic therapy that could lead to improved quality of life and decreased reliance on medication. However, further research is needed to guide clinical application, particularly in complex pain patients.
ABSTRACT
A patient underwent C2-T2 decompression and fusion with excessive intraoperative bleeding and no clear source. The patient denied the use of blood-thinning medications, but had consumed the equivalent of 12 g garlic daily in the days leading up to the surgery. He was treated with desmopressin acetate (DDAVP) and cryoprecipitate with adequate control of bleeding. Garlic is known to have an antiplatelet effect, although the dose range necessary to create a bleeding abnormality has not yet been well described nor has the effect of taking garlic with sertraline or other agents with an established or potential effect on coagulation.
Subject(s)
Blood Loss, Surgical , Decompression, Surgical/methods , Garlic/adverse effects , Hemostasis, Surgical/methods , Spinal Fusion/methods , Spinal Stenosis/surgery , Aged , Blood Loss, Surgical/prevention & control , Humans , Male , Treatment OutcomeABSTRACT
PURPOSE: This narrative review provides an overview of the complementary and alternative medicine (CAM) therapies that anesthesiologists and pain management practitioners commonly encounter along with recommendations for evaluation and implementation. SOURCE: A literature search of PubMed was performed using the comprehensive MeSH term, "Complementary Therapies OR Dietary Supplements", and a search was conducted of the various licensing organizations and books published on the topics of CAM and integrative medicine. PRINCIPAL FINDINGS: In North America, the most commonly encountered CAM therapies include 1) manipulation and procedural therapies; 2) herbs, nutritional supplements (nutraceuticals), and dietary therapies; and 3) mind-body and energy therapies. Controversy exists regarding many of these therapies, particularly those with a higher risk of harm, such as chiropractic manipulation, acupuncture, and nutraceutical use. Several well-conducted studies were analyzed to show how research in CAM can control for placebo responses. Practical considerations are provided for patients and practitioners interested in pursuing or already employing CAM in perioperative and chronic pain management settings. CONCLUSIONS: Complementary and alternative medicine therapies in general may provide a useful adjunct in the management of chronic pain. Nevertheless, many patients are not aware of the risks and benefits of individual therapies. In the perioperative setting, the most concerning CAM therapy is the use of herbs and other supplements that may produce physiologic and metabolic derangements and may interact with prescription medications. Resources exist to aid pain specialists, anesthesiologists, and patients in the evidence-based utilization of CAM therapies.
Subject(s)
Anesthesiology , Complementary Therapies , Dietary Supplements , Humans , Mind-Body Therapies , Musculoskeletal Manipulations , Pain ManagementABSTRACT
This study examined the short- and long-term neuroprotective and analgesic activity of honokiol (a naturally occurring lignan isolated from Magnolia) on developing brains in neonates exposed to inflammatory pain, known to cause neuronal cell death. Postnatal day 4 (P4) neonatal rat pups were subjected to intraplantar formalin injection to four paws as a model of severe neonatal pain. Intraperitoneal honokiol (10 mg/kg) or corn oil vehicle control was administered 1 h prior to formalin insult, and animals were maintained on honokiol through postnatal day 21 (P21). Behavioral tests for stress and pain were performed after the painful insult, followed by morphological examinations of the brain sections at P7 and P21. Honokiol significantly attenuated acute pain responses 30 min following formalin insult and decreased chronic thermal hyperalgesia later in life. Honokiol-treated rats performed better on tests of exploratory behavior and performed significantly better in tests of memory. Honokiol treatment normalized hippocampal and thalamic c-Fos and hippocampal alveus substance P receptor expression relative to controls at P21. Together, these findings support that (1) neonatal pain experiences predispose rats to the development of chronic behavioral changes and (2) honokiol prevents and reduces both acute and chronic pathological pain-induced deteriorations in neonatal rats.
Subject(s)
Analgesics/pharmacology , Biphenyl Compounds/pharmacology , Lignans/pharmacology , Magnolia/chemistry , Neuroprotective Agents/pharmacology , Pain/drug therapy , Animals , Biphenyl Compounds/chemistry , Formaldehyde , Lignans/chemistry , Male , Molecular Structure , Pain/chemically induced , RatsABSTRACT
Thrombin's role in the nervous system is not well understood. Under conditions of blood-brain barrier compromise (e.g., neurosurgery or stroke), thrombin can result in neuroapoptosis and the formation of glial scars. Despite this, preconditioning with thrombin has been found to be neuroprotective in models of cerebral ischemia and intracerebral hemorrhage. We investigated the effects of physiologically relevant concentrations of thrombin on cortical neurons using two culture-based assays. We examined thrombin's effect on neurites by quantitative analysis of fluorescently labeled neurons. To characterize thrombin's effects on neuron survival, we spectrophotometrically measured changes in enzymatic activity. Using receptor agonists and thrombin inhibitors, we separately examined the role of thrombin and its receptor in neuroprotection. We found that low concentrations of thrombin (1 nM) enhances neurite growth and branching, neuron viability, and protects against excitotoxic damage. In contrast, higher concentrations of thrombin (100 nM) are potentially detrimental to neuronal health as evidenced by inhibition of neurite growth. Lower concentrations of thrombin resulted in equivalent neuroprotection as the antifibrinolytic, aprotinin, and the direct thrombin inhibitor, argatroban. Interestingly, exogenous application of the species-specific thrombin inhibitor, antithrombin III, was detrimental to neuronal health; suggesting that some endogenous thrombin is necessary for optimal neuron health in our culture system. Activation of the thrombin receptor, protease-activated receptor-1 (PAR-1), via micromolar concentrations of the thrombin receptor agonist peptide, TRAP, did not adversely affect neuronal viability. An optimal concentration of thrombin exists to enhance neuronal health. Neurotoxic effects of thrombin do not involve activation of PAR receptors and thus separate pharmacologic manipulation of thrombin's receptor in the setting of direct thrombin inhibitors could be a potential neuroprotective strategy.