General Approach to Management of Intoxication PDF

Principles of Toxicology 1140-115 General Approach to Management of Intoxication Dr. Bedoor Qabazard Objectives: By the end of all lectures the student should be able to: Know the principles of treating and managing poisoning (clinical toxicol...

Principles of Toxicology 1140-115 General Approach to Management of Intoxication Dr. Bedoor Qabazard Objectives: By the end of all lectures the student should be able to: Know the principles of treating and managing poisoning (clinical toxicology). Describe supportive care measures for treating seriously intoxicated persons. Identify & compare the various strategies for decreasing poison absorption (GI decontamination, AC, emesis, gastric lavage, WBI). Discuss different techniques for enhancing poison elimination (dialysis, hemoperfusion, alteration of urine pH). Recognize the basic toxicologic features and treatment of poisoning with some agents, such as carbon monoxide, cyanide, alcohols, acetaminophen, salicylates and others.  Introduction Poisoning is an adverse effect from a chemical, drugs, or other xenobiotics that have been taken in excessive amounts. The body is able to tolerate or detoxify a certain dose of a chemical; however, once a critical threshold is exceeded, toxicity results. Poisoning can produce minor local effects that can be treated readily or systemic life-threatening effects that require intensive medical intervention. Clinical toxicology is concerned with the pathophysiological changes caused by exposure to toxic agents, and symptoms and management of intoxicated persons. Case A 16-year-old female patient arrives in the ED by ambulance after being found by a parent in what appeared to be an intoxicated state with empty pill bottles scattered about her room. The patient was given 1.5 g/kg oral activated charcoal as a slurry in a sorbitol cathartic and placed in the intensive monitoring section of the ED while the laboratory tests were being performed. Forty minutes later, the laboratory results returned and showed liver transaminase values were elevated at approximately three times the upper limit of normal Principles of Poisoning Treatment and Management 1- Initial stabilization and supportive care (ABCD approach) 2- Diagnostic assessment and laboratory evaluation 3- Decontamination 4- Enhancing Elimination of poisons 5- Administration of specific antidotes  Pre-Hospital Care: First Aid for Poison Exposures Inhaled poison Immediately get the person to fresh air. Avoid breathing fumes. Open doors and windows. If victim is not breathing, start artificial respiration. Poison on the skin Remove contaminated clothing and flood skin with water for 10 minutes. Wash gently with soap and water and rinse. Avoid further contamination of victim or first aid providers. Poison in the eye Flood the open eye with water. Repeat for 10 to 15 continuous minutes. Remove contact lenses. Avoid ocular vasoconstrictor drops. Swallowed poison Provide supportive care. 1- Initial stabilization and supportive care (ABCD approach) Airways: no obstruction by vomit or flaccid tongue. Breathing: maintain adequate oxygenation and ventilation. oxygenmask Circulation: maintain perfusion of vital organs. checkBP HR Drugs: treatment of comatose pt using ‘coma cocktail’: composenknow *Dextrose (50 mL D50W IV) to treat hypoglycemia. vitBI *Thiamine (100 mg IV) to avoid or treat Wernicke’s f arm IE encephalopathy following dextrose loading (esp. for alcoholics). *Naloxone (0.4-2 mg IV) for suspected opioid poisoning. 0 *Flumazenil (controversial !) Placing the patient on the left side may afford easier clearance of the airway if emesis occurs and may slow drug absorption from GIT. Management of seizures, arrhythmias, hypotension, acid-base balance, fluid/electrolytes status, & hypoglycemia.  ptconditionisstable 2- Diagnostic assessment and laboratory evaluation o Obtaining history of exposure o Identify the substance(s) ingested & quantity; route & duration of exposure; signs & symptoms of overdose or any illness. o Physical examination oNeurological examination: evaluates any seizures, altered consciousness, confusion, ataxia, slurred speech, tremor, headache. oCardiopulmonary examination: evaluates any syncope, palpitations, cough, chest pain, SOB, or irritation of upper airways. oGIT examination: evaluates any abdominal pain, nausea, vomiting, diarrhea, or difficulty in swallowing. o Past medical history oMedications, alcohol, drug abuse, allergies, prior ingestion, travel, social history, psychiatric history, pregnancy. o Routine laboratory assessment afterstabilization of pt oCBC, serum electrolytes, BUN, Scr, blood glucose, urine analysis, ECG, chest/kidney/bladder X-rays. after 1 4hrs exposure totoxicagent 3- Decontamination (preventing absorption) o Skin Decontamination Ig Should be performed when percutaneous absorption of a substance may result in systemic toxicity, or when a local toxic effect may occur (e.g., acid burns). Contaminated clothing is removed & the area is irrigated with large quantities of water. Neutralization should NOT be attempted. acid base antidoteis02 o Inhaled poison test 5h1to fresh air, avoid breathing fumes, open a tf Immediately get the person doors & windows. Artificial respiration if patient is not breathing. o Gastric Decontamination (a) Emesis with Ipecac syrup (no longer recommended/not for corrosives) Pa (b) Gastric lavage This 4 tube Fci locally (c) Single-Dose Activated Charcoal (d) Cathartics laxiative t (e) Whole Bowel Irrigation (WBI) this IÉ Gastric Decontamination: Gastric Lavage (stomach wash) The placement of an orogastric tube and washing out of the gastric contents through repetitive instillation and withdrawal of fluid. May be considered only if a potentially toxic agent has been ingested within the past 1 hour. Not in unconscious patient unless intubated (risk of aspiration) Contraindications: ingestion of a corrosive (strong acid or alkali) or hydrocarbon agent (high aspiration risk). has Complications: aspiration pneumonitis, laryngospasm, mechanical injury to the oesophagus and stomach, hypothermia, and fluid and electrolyte imbalance. Gastric Decontamination: Gastric Lavage Performed with warm (37°C to 38°C) normal saline or tap water until the gastric return is clear; this usually requires 2-4 L of fluid instilled in small volumes of 50-100 ml in children or 200-300 ml in adults at one time to avoid pushing the poison into the intestine. When the lavage is complete, the stomach may be left empty or an antidote may be instilled through the tube. If no specific antidote is known for the poison, an aqueous suspension of activated charcoal and a cathartic is often given. Usually used in combination with activated charcoal: AC/GL/AC.  left IFadarco Gastric lavage using Y-tube say to 5 4 W laciative mention telemination tabs Gastric Decontamination: Single-Dose Activated Charcoal It is a highly purified, adsorbent form of carbon that prevents GI absorption of a drug by chemically binding (adsorbing) the drug to the charcoal surface. Adsorbs almost all commonly ingested drugs & chemicals & is usually administered to most overdose patients as quickly as possible. AC provides the most consistent efficacy & best safety profile. gas Not effective for cyanide, me iron, lead, lithium, alcohols, and corrosives. Dosage: - Activated charcoal is most effective when given within the first few hours after ingestion, ideally within the first hour. Mixed with water or sorbitol (laxative effect). - Adult dose:- 25 -100 g as a single dose - Children dose:- 1 to 12 years: 25 - 50 g;