Management of Poisoning MOH Clinical Practice Guidelines Dec/2011 Health Ministry of Sciences Chapter of Emergency College of College of Family Manpower Authority Physicians Physicians, Physicians Academy of Medicine, Singapore Singapore Singapore Ministry of Health, Singapore College of Medicine Building 16 College Road Singapore 169854 Singapore Medical Pharmaceutical Society Society for Emergency Toxicology Singapore Paediatric TEL (65) 6325 9220 Association of Singapore Medicine in Singapore Society (Singapore) Society FAX (65) 6224 1677 WEB www.moh.gov.sg ISBN 978-981-08-9904-2 December 2011 Levels of evidence and grades of recommendation Levels of evidence Level Type of Evidence 1+ + High quality meta-analyses, systematic reviews of randomised controlled trials (RCTs), or RCTs with a very low risk of bias 1+ Well-conducted meta-analyses, systematic reviews of RCTs, or RCTs with a low risk of bias 1- Meta-analyses, systematic reviews of RCTs, or RCTs with a high risk of bias 2+ + High quality systematic reviews of case control or cohort studies. High quality case control or cohort studies with a very low risk of confounding or bias and a high probability that the relationship is causal 2+ Well conducted case control or cohort studies with a low risk of confounding or bias and a moderate probability that the relationship is causal 2- Case control or cohort studies with a high risk of confounding or bias and a signifi cant risk that the relationship is not causal 3 Non-analytic studies, e.g. case reports, case series 4 Expert opinion Grades of recommendation Grade Recommendation A At least one meta-analysis, systematic review of RCTs, or RCT rated as 1+ + and directly applicable to the target population; or A body of evidence consisting principally of studies rated as 1+, directly applicable to the target population, and demonstrating overall consistency of results B A body of evidence including studies rated as 2++, directly applicable to the target population, and demonstrating overall consistency of results; or Extrapolated evidence from studies rated as 1+ + or 1+ C A body of evidence including studies rated as 2+, directly applicable to the target population and demonstrating overall consistency of results; or Extrapolated evidence from studies rated as 2+ + D Evidence level 3 or 4; or Extrapolated evidence from studies rated as 2+ G P P Recommended best practice based on the clinical experience of the (good guideline development group practice points) CLINICAL PRACTICE GUIDELINES Management of Poisoning MOH Clinical Practice Guidelines December/2011 Published by Ministry of Health, Singapore 16 College Road, College of Medicine Building Singapore 169854 Printed by Golden City Colour Printing Co. (Pte.) Ltd. Copyright © 2011 by Ministry of Health, Singapore ISBN 978-981-08-9904-2 Available on the MOH website: http://www.moh.gov.sg/cpg Statement of Intent These guidelines are not intended to serve as a standard of medical care. Standards of medical care are determined on the basis of all clinical data available for an individual case and are subject to change as scientifi c knowledge advances and patterns of care evolve. The contents of this publication are guidelines to clinical practice, based on the best available evidence at the time of development. Adherence to these guidelines may not ensure a successful outcome in every case, nor should they be construed as including all proper methods of care or excluding other acceptable methods of care. Each physician is ultimately responsible for the management of his/her unique patient in the light of the clinical data presented by the patient and the diagnostic and treatment options available. Contents Page Executive summary of recommendations 1 1 Poison management systems 36 2 Principles of management of acute poisoning 55 3 Decontamination after poisoning 62 Enhancing the elimination of toxic substances from the 4 75 body 5 Antidotes 80 6 Analgesics 84 7 Antihistamines / Anticholinergics 118 8 Psychotropics 126 9 Organophosphates 152 10 Industrial chemicals 171 11 Caustics / detergents 179 12 Bites and stings 186 Annex A: Commonly-used antidotes 199 Annex B: Serum toxicity ranges and toxicology 255 laboratory services in Singapore Annex C: Socio-psychiatric aspects of poisons 265 management Annex D: Resources for industrial chemical 270 exposure Annex E: Alternative medicine 275 References 281 Self-assessment (MCQs) 328 Workgroup members 334 Acknowledgements 336 Foreword It is estimated that 350,000 people died worldwide from unintentional poisoning in 2002.1 In Singapore, injuries (including poisoning) ranked as the fi fth leading cause of death and the leading cause of hospitalisation from 2007 to 2009. The pattern of poisoning has changed as the public is now exposed to other new drugs and chemicals. New antidotes and therapies have also been developed for the management of such poisoning, and are now available to health professionals. The Ministry of Health released its fi rst handbook on management of poisoning twenty years ago with the objective of providing a quick and reliable reference for the complex management of drug overdoses / poisoning. In 2000, a newer edition of the handbook was published to meet the changing needs. This edition of the guideline updates the May 2000 guideline with a greater focus on the principles of emergency management of poisoning and the common toxins in the local context. A multidisciplinary expert workgroup reviewed the best available evidence from scientifi c literature and with their expertise in this area, has updated the guideline to assist healthcare professionals in the management of drug overdoses and poisoning. I hope this set of recommendations will be useful for healthcare professionals, particularly physicians, pharmacists and clinicians who are involved in the management and care of patients with drug overdoses and poisoning. PROFESSOR K SATKU DIRECTOR OF MEDICAL SERVICES 1 WHO Data: Poisoning Prevention and Management [Internet]. Th e International Programme on Chemical Safety (IPCS) [cited 5 September 2010]. Available from: http://www.who.int/ipcs/poisons/en/. Executive summary of key recommendations Details of recommendations can be found in the main text at the pages indicated. Principles of management of acute poisoning – resuscitating the poisoned patient GPP In a critically poisoned patient, measures beyond standard resuscitative protocol like those listed above need to be implemented and a specialist experienced in poisoning management should be consulted (pg 55). GPP D Prolonged resuscitation should be attempted in drug-induced cardiac arrest (pg 55). Grade D, Level 3 C Titrated doses of naloxone, together with bag-valve-mask ventilation, should be administered for suspected opioid-induced coma, prior to intubation for respiratory insuffi ciency (pg 56). Grade C, Level 2+ D In bradycardia due to calcium channel or beta-blocker toxicity that is refractory to conventional vasopressor therapy, intravenous calcium, glucagon or insulin should be used (pg 57). Grade D, Level 3 B Patients with actual or potential life threatening cardiac arrhythmia, hyperkalaemia or rapidly progressive toxicity from digoxin poisoning should be treated with digoxin-specifi c antibodies (pg 57). Grade B, Level 2++ B Titrated doses of benzodiazepine should be given in hyperadrenergic- induced tachycardia states resulting from poisoning (pg 57). Grade B, Level 1+ D Non-selective beta-blockers, like propranolol, should be avoided in stimulant toxicity as unopposed alpha agonism may worsen accompanying hypertension (pg 57). Grade D, Level 3 D Physostigmine should be considered for treating tachycardia resulting from pure anticholinergic poisoning (pg 58). Grade D, Level 3 1 GPP Lidocaine is the drug of choice for most ventricular arrhythmias due to drug toxicity (pg 58). GPP C Sodium bicarbonate should be used in impaired conduction defect caused by sodium channel blocking agents such as tricyclic antidepressants (pg 58). Grade C, Level 2+ B Titrated doses of benzodiazepine can be used to treat hypertension associated with drug-induced hyperadrenergic states (pg 59). Grade B, Level 1+ D High dose vasopressor therapy for hypotension caused by poisoning needs to be titrated to response and complications (pg 59). Grade D, Level 3 D Calcium chloride or gluconate can be given for calcium-channel blocker overdose (pg 59). Grade D, Level 3 D Glucagon can be given for beta-blocker and calcium-channel blocker overdose (pg 59). Grade D, Level 3 D High dose insulin euglycaemia therapy (HIE) is effi cacious for use during calcium-channel and beta-blocker overdose (pg 60). Grade D, Level 3 D Life support with circulatory assist device, such as intra-aortic balloon pump and bypass circuits (example: extracorporeal life support system) should be considered in severe refractory hypotension that is unresponsive to maximal medical therapy. Deployment of these devices should be preplanned in advance (pg 60). Grade D, Level 3 GPP For poisoned patients presenting with depressed conscious level due to unspecifi ed drugs, the following treatment should be considered: naloxone, glucose, oxygen and thiamine (pg 60). GPP B Routine toxicology screen for poisoning agents in the blood and urine or other body fl uids is not advised (pg 60). Grade B, Level 1- 2 D Checking serum paracetamol level should be considered, especially in a situation of parasuicide where the history may not be forthcoming. Paracetamol is the most common drug involved in parasuicides locally and is readily amenable to treatment with antidotes (pg 61). Grade D, Level 4 D Patients, who ingested drugs that are of sustained-release formulation; have a prolonged half-life; or active metabolites that have prolonged effects, should be observed for a longer period of time (pg 61). Grade D, Level 4 Decontamination after poisoning Single dose activated charcoal C Single dose activated charcoal is indicated as a gastric decontaminant agent if a patient has ingested a potentially toxic amount of a poison up to 1 hour following ingestion (pg 62). Grade C, Level 2+ GPP The recommended dose for activated charcoal is as follows (pg 63): • Children up to 1 year of age: 10-25 g or 0.5 – 1 g/kg.