The perioperative implications of herbal medicines

Transcription

1 The perioperative implications of herbal medicines By Nicole LaRocca, BSN, CCRN, SRNA, and Tandy Gustin, BSN, CCRN, SNRA The use of Complementary and Alternative Medicine (CAM) is prevalent among individuals requiring surgery. CAM is a broad field encompassing a diverse group of medical and healthcare systems and products that aren t part of conventional Western medicine. The types of CAM include mind and body medicine, manipulative and movement therapies, and natural products, such as herbal medicines. For more information about the different types of CAM, see the National Center for Complementary and Alternative Medicine s website at This article examines one of the most common types of CAM: herbal medicines. The growing use of herbal medicine has led to guidelines designed to inform healthcare providers and patients about potentially adverse consequences associated with herbal medicines and anesthesia. 1,2 Organizations including the American Association of Nurse Anesthetists (AANA), American Society of Anesthesiologists (ASA), and American Society of Regional Anesthesia (ASRA) recommend caution when caring for patients taking herbal medicines, as they aren t subjected to the same level of scrutiny and research requirements as prescription drugs or over-the-counter medications. The FDA addresses the misconception that, although these products are considered natural, they aren t necessarily free from harm. 3 In 2004, the FDA specifically recommended removing over-the-counter, Ephedra-containing products from the U.S. market. According to current ASRA recommendations, herbal medicines don t interfere with the performance of neuraxial techniques. 4 Mandatory discontinuation of herbal medicines, avoidance of regional techniques, and reversal of their effects on hemostasis preoperatively are considered unnecessary at this time. 4 Despite these guidelines, current research is studying the effects of herbal medicines on physiologic processes and specific alterations of metabolic enzyme functions. The AANA continues to recommend that patients discontinue herbal medicines at least 1 to 2 weeks prior to surgery. 3 The ASA hasn t published a position statement on herbal medicines except to support the AANA s recommendations. There are numerous herbal medicines that have potentially deleterious effects on patients, especially in the perioperative setting. Because their potency and purity depend on the manufacturer and distributor, significant variations in efficacy and adverse reactions may occur. The lack of standardization coupled with educational deficits among users and providers raises the risk of adverse physiologic reactions. 5 Greater awareness and understanding among healthcare providers regarding these alternative remedies are necessary to provide optimal patient care. May OR Nurse

2 Background Current evidence has identified a knowledge deficit about herbal medicines among healthcare providers. A recent investigation demonstrated that only 23% of anesthesia providers were aware of the current recommendations to discontinue supplements up to 2 weeks prior to surgery. 5 Additionally, providers scored only 21% when surveyed about the adverse reactions of common herbal medicines. 5 Research has also identified that both physicians and nurses poorly document the use of herbal medicines among their patients. Ninety percent of healthcare providers failed to assess patient use of herbal medicines during the preoperative assessment. 1 Over 85% of the participants requested further educational opportunities on herbal medicine uses and adverse reactions. 5,6 Regulation and quality control The lack of evaluation and safety reporting processes for herbal medicines means there s no standardization. This lack of organizational control leads to inconsistent potencies and pharmacologic activity. 7,8 Additionally, 39% of drug trials didn t address the potential for adverse reactions. 7 Because the FDA doesn t consider herbal medicines to be formal medications, they aren t subject to pharmaceutical regulations. 7,9 At this time, the only requirement for the manufacturers of these products is to send a copy of the product label to the FDA. 10 A variety of contaminants, including toxic metals, have been found in herbal supplements. 10 The lack of standardization makes it difficult for practitioners to advocate for patients and educate themselves on the adverse reactions and drug interactions of herbal medicines. The use of herbal medicines is rising, and the consequences of drug-herb interactions are becoming more significant. Induction (increases regulation) and inhibition (decreases regulation) of hepatic enzymes (the cytochrome oxidase family known as the CYP 450 enzymes) are currently being investigated. Many herbal medicines share the same metabolic pathways and drug transporters as drugs used in the perioperative period, including the specific enzymes glucuronosyltransferases and P-glycoprotein. 11 The The use of herbal medicines is rising, and the consequences of drug-herb interactions are becoming more significant. implications of this information are striking. Not only must anesthesia providers consider the herbal medicines that patients are taking, they must also understand the interactions of these substances with other perioperative medications. With more research focusing on the induction or inhibition of CYP450 enzymes, anesthesia providers will have the knowledge to provide safer and more evidencebased care. Clinically significant herbal medicines The following is a brief overview of some of the more common and noteworthy herbal medicines that may be encountered in everyday practice. The generic name appears first, the Latin name is in italics, followed by other common names in parentheses. Black Cohosh Actaea racemosa (black bugbane, black snakeroot, fairy candle) contains triterpene glycosides used to treat symptoms of menopause 12 acts on estrogen and serotonin receptors. 13 Triterpene glycosides are organic plant toxins and are considered the active ingredient in Black Cohosh. 12 inhibition of the CYP450 3A4 enzymes: Cytochrome P450 enzymes are a major source of drug metabolism. Inhibition may potentiate certain drugs that are metabolized by this pathway, including amiodarone, erythromycins, metoprolol, carvedilol, amlodipine, diltiazem, benzodiazepines, and warfarin. hepatoxicity should be avoided during pregnancy and lactation. 12 Echinacea Echinacea angustifolia (American coneflower, black sampson, comb flower) improved wound healing immune system enhancement arthritis therapy inhibits CYP450 3A4 enzymes tachyphylaxis if use exceeds 8 weeks 10 activates cell-mediated immunity causing allergic 18 OR Nurse 2013 May

3 reactions and reducing the actions of immunosuppressants 14 potential for wound infection with long-term use 6 hepatotoxicity when taken with other hepatotoxic drugs. 6 Ephedra Ephedra sinica (Ma huang) weight loss stimulatory effects that are similar to caffeine. cardiovascular toxicity leading to dysrhythmias, hypertension, myocardial infarction, stroke, seizure, psychosis, and anxiety inhibition of antihypertensive, antiseizure, and benzodiazepine medications severe hypertension can be seen when used with Monoamine Oxidase Inhibitors (MAOIs) 14 similar formulations exist, such as synephrine, which inhibits CYP450 3A4. 12 Feverfew Tanacetum parthenium (altamisa, chrysanthemum parthenium, pyrethrum parthenium, and wild chamomile) treatment of migraine headaches attenuation arthritis pain. inhibits platelet activity, bleeding risk. 10 Garlic Allium sativum antimicrobial immune system enhancement (used by HIV-positive patients) coronary artery disease prevention antihypertensive lipid lowering. 10,11 decreased platelet aggregation and potentiation of antiplatelet medications, including warfarin, heparin, aspirin, and NSAIDS. 9 While garlic can effect coagulation for up to 7 days, ASRA isn t formally recommending discontinuation of this herb prior to neuraxial anesthesia. 4 Ginger Zengiber Officinalis prevention of nausea and motion sickness 9 anti-inflammatory. inhibits platelet aggregation In a recent open-label, three-way crossover randomized controlled trial, healthy volunteers had no change in their international normalized ratio or platelet count associated with taking ginger. 8 Ginkgo Ginkgo Biloba (maidenhair tree) treatment of peripheral vascular disease improved symptoms of macular degeneration relief from vertigo dissipate cognitive dysfunctions (Alzheimer s disease) antioxidant properties minimize erectile dysfunction memory and cognition enhancement. 11 inhibitor of platelet activating factor (PAF) 15 perioperative bleeding. 16 Ginseng Panax Ginseng (Panax) BP management lipid lowering cognition enhancement lessen fatigue ulcer healing neuroprotection cancer prevention antioxidant properties immune system enhancement. 17 possible enhanced clearance of warfarin (research has yet to support this claim) increases the clearance of alcohol by 30% due to its induction of the CYP 2E1 enzyme hypertensive interactions with select MAOIs 18 possible delay in gastric emptying (cause for concern with patients who are high risk for aspiration). 10,12 Kava Piper methysticum (Kava Kava) sedative and anxiolytic properties by enhancing Gamma aminobutyric acid (GABA) 19 inhibitory neurotransmission. 10 potentiate the effects of both barbiturates and benzodiazepines liver failure May OR Nurse

4 St. John s wort Hypericum perforatum (Johnsroot, SJW) treat mild-to-moderate depression. 19 induces specific CYP 450 enzymes; potential to decrease duration of action interacts with over 30 commonly used medications including digoxin, erythromycin, ibuprofen, midazolam, nifedipine, omeprazole, oral contraceptives, phenytoin, verapamil, and warfarin. 11,20 Valerian Valeriana officinalis (valerian root) lessen anxiety and nervous tension promote sleep smoking cessation ease congestion relieve muscle spasms treat or prevent cancer. decreases sleep latency through enhancement of GABA neurotransmission potentiates the effects of barbiturates amplifies the effects of sedatives and anxiolytics. 10 The herbal medicines discussed above are among the most commonly seen in the perioperative setting. However, the list of herbal medicines and dietary supplements used by patients is growing. Ellagic acid (EA) is a product currently undergoing scrutiny. EA is a dietary supplement and polyphenol compound found in fruits, including strawberries, raspberries, and pomegranates; it s also found in nuts, such as pecans and walnuts. Therapeutic uses include antiinflammatory and antinociceptive properties, free radical scavenging, anticoagulation, and depressed tumor genesis, especially prostate cancer cells. The proposed anticoagulation has been attributed to the inhibition of the Hageman factor. Hageman factor, also known as Factor XII, is a plasma protein that contributes to clotting in the common pathway of the coagulation cascade. EA inhibits a number of cell-signaling pathways that are important to tumor growth. This inhibition is demonstrated in inflammatory signaling through tumor necrosis factor alphainduced COX-2 expression as well as nitric oxide synthase inhibition. 21,22 Animal research indicates that concurrent administration of EA and ketorolac (a nonopioid analgesic) may cause a significant decrease in platelet activity resulting in increased Summary of physiologic effects of herbal medicines 23 Herbal medicines that may cause bleeding Garlic Ginger Ginkgo Ginseng Echinacea Feverfew Ellagic acid (a dietary supplement) Herbal medicines that may cause hypoglycemia Garlic Ginseng Herbal medicines that affect the cardiovascular (CV) system Black cohosh (decreases BP) Ephedra (increases CV stimulation) Ginseng (increases CV stimulation) Herbal medicines that affect the central nervous system (CNS) Ephedra (increases CNS stimulation) Feverfew (increases CNS stimulation) Ginseng (increases CNS stimulation) Kava (decreases CNS stimulation) St. John s Wort (increases CNS stimulation) Valerian (decreases CNS stimulation) Herbal medicines that may be hepatotoxic Echinacea Kava St. John s Wort blood loss. 21,22 Further research, namely human trials, is necessary to determine EA s effects on COX-2 and additional contributions to pain management. Summary The best approach for the perioperative nurse in assessing and caring for patients is to begin with a thorough preoperative assessment to guide interventions and avoid potential adverse reactions (see Summary of physiologic effects of herbal medicines). The preoperative assessment should begin 2 weeks prior to surgery during the initial telephone or preoperative evaluation. Patients must be educated about the 20 OR Nurse 2013 May

5 importance of stopping all herbal medicines 2 weeks prior to surgery. This approach involves asking patients directly about their herbal medicine use, educating them about what herbal medicines are, and explaining why disclosure is a safety issue. On the day of surgery, perioperative nurses need to confirm that the patient has complied with the discontinuation instructions. In order to effectively educate patients, nurses must first possess a thorough understanding of herbal medicines and their potential impacts. Further research will assist all clinicians in anticipating drug and procedural interactions that may result from herbal medicine use. OR REFERENCES 1. Temple MD, Fagerlund K, Saewyc E. A national survey of certified registered nurse anesthetists knowledge, beliefs, and assessment of herbal supplements in the anesthesia setting. AANA J. 2005;73(5): Collins D, Oakey S, Ramakrishnan V. Perioperative use of herbal, complementary, and over the counter medicines in plastic surgery patients. Eplasty. 2011;11:e Using Herbal Products Safely. AANA Documents/herbal_english.pdf. 4. Horlocker TT, Wedel DJ, Rowlingson JC, et al. Regional anesthesia in the patient receiving antithrombotic or thrombolytic therapy: American Society of Regional Anesthesia and Pain Medicine Evidence-Based Guidelines. Reg Anesth Pain Med. 2010;35(1): Mikail CN, Hearney E, Nemesure B. Increasing physician awareness of the common uses and contraindications of herbal medicines: utility of a case-based tutorial for residents. J Altern Complement Med. 2003; 9(4); Skinner CM, Rangasami J. Preoperative use of herbal medicines: a patient survey. Br J Anaesth. 2002;89(5): Turner LA, Singh K, Garritty C, et al. An evaluation of the completeness of safety reporting in reports of complementary and alternative medicine trials. BMC Complement Altern Med. 2011;11: Lee A, Chui PT, Aun CS, Lau AS, Gin T. Incidence and risk of adverse perioperative events among surgical patients taking traditional Chinese herbal medicines. Anesthesiology. 2006;105(3): Pradhan SL, Pradhan PS. Ayurvedic medicine and anaesthesia. Indian J Anaesth. 2011;55(4): Rowe DJ, Baker AC. Perioperative risks and benefits of herbal supplements in aesthetic surgery. Aesthet Surg J. 2009;29(2): Chen XW, Serag ES, Sneed KB, et al. Clinical herbal interactions with conventional drugs: from molecules to maladies. Curr Med Chem. 2011;18(31): Tachjian A, Maria V, Jahangir A. Use of herbal products and potential interactions in patients with cardiovascular diseases. J Am Coll Cardiol. 2010;55(6): Dinman S. Black cohash: a contraindication in general anesthesia. Plast Surg Nurs. 2006;26(1): Ang-Lee MK, Moss J, Yuan CS. Herbal medicines and perioperative care. JAMA. 2001;286(2): Norred CL, Finlayson CA. Hemorrhage after the preoperative use of complementary and alternative medicines. AANA J. 2000;68(3): King AR, Russett FS, Generali JA, Grauer DW. Evaluation and implications of natural product use in preoperative patients: a retrospective review. BMC Complement Altern Med. 2009;9: Qi LW, Wang CZ, Du GJ, Zhang ZY, Calway T, Yuan CS. Metabolism of ginseng and its interactions with drugs. Curr Drug Metab. 2011;12(9): Norred CL. Complementary and alternative medicine use by surgical patients. AORN J. 2002;76(6): Holcomb SS. Common herb-drug interactions: what you should know. Nurse Pract. 2009;34(5): Di YM, Li CG, Xue CC, Zhou SF. Clinical drugs that interact with St. John s wort and implication in drug development. Curr Pharm Des. 2008;14(17): Gainok J, Daniels R, Golembiowski D, et al. Investigation of the anti-inflammatory, antinociceptive effect of ellagic acid as measured by digital paw pressure via the Randall-Selitto meter in male Sprague- Dawley rats. AANA J. 2011;79(suppl 4):S28-S Attilio P, Merritt C, Sims J, Kane N, O Sullivan J. The effect of ellagic acid on platelet activation as measured by the quantification of P-selectin using flow cytometry. AANA J. 2010;78(6): QuickFacts by Core Concepts Anesthesia Review, LLC. Barash P, Cullen B, Stoelting R, Calahan M, Stock M. Clinical Anesthesia. Philadelphia: Lippincott Williams & Wilkins; 2009:562. Nicole LaRocca is an SRNA in the MSNA/DNAP program at Virginia Commonwealth University, Richmond, Va. Tandy Gustin is an SRNA in the MSNA/DNAP program at Virginia Commonwealth University, Richmond, Va. The authors have disclosed that they have no financial relationships related to this article. DOI /01.ORN May OR Nurse