Approach to Acute Poisoning By Adel Altamimi,MD EM consultant

paracetamol before one hour , he is fully conscious ,alert 25 years male present after ingestion of 20 tap of paracetamol before one hour , he is fully conscious ,alert and vital signs are stable. Next step? induce vomiting gastric lavage activated charcoal extract blood for investigation and send for level at 4 hours

16 years female present with sever decrease in level of conscious after ingestion of large amount of epilepsy medication She is unconscious, normal BP and HR Next step? NG and gastric lavage intubated and ventilated CT brain IV fluids

30 years K/C of depression came with tonic colonic SZ aborted with Benz , the patient intubated because of decrease level of conscious , BP 100/60 HR 160 Next step CT brain EEG ECG TOX screen

Acute poisoning is a dynamic medical illness usually representing an acute and potentially life threatening exacerbation of a chronic underlying psychosocial disorder. the patient’s form a heterogeneous group that requires a systematic approach based on early resuscitation where needed, risk assessment to guide further management and early consideration of the underlying psychosocial issues. the overall mortality rate from drug overdose and poison exposure is 0.05 %. the mortality rate for hospitalized patients is approximately 1 to 2 %.

5% of all ICU admission . Acute poising : account for 5 to 10 percent of all emergency department visits. 5% of all ICU admission . The most commonly implicated poisoning exposures were due to analgesics .

Toxidrome: Physical findings attributed to a specific class of toxins that can provide important clues to narrow the differential diagnosis.

The general rules have many exceptions, and polydrug overdoses may result in overlapping and confusing mixed syndromes.

General Approach : Resuscitation Examination Risk assessment Investigation Decontamination Antidotes. Supportive Therapy . Disposition .

Resuscitation: initial assessment and treatment should target potential life threats and occur in an appropriately staffed and equipped resuscitation area. extended ABC approach ( low threshold of intubation). VITAL SIGNS !

Consider intubation in depress level of conscious. sever acidosis respiratory failure. risk of aspiration (gastric lavage)

Early detection of Seizure ( benzodiazepein) Hypoglycemia Hypothermia Hypotension Arrhythmia.

in cardiac arrest from toxicological causes , resuscitation should be prolonged.

Examination: Detailed examination: Vital signs Eyes Mucous Membranes Breath and Bowel sounds Skin Assessment Reflexes

Risk assessment : Agent(s) Dose(s) Time since ingestion Current clinical status Patient factors

Investigation: ECG and paracetamol level are the only routine tests. ECG provide diagnostic and prognostic information. Urine toxicology screens are of little use in the acute setting.

Further tests are required as indicated by the specific presentation calculate the Anion gap

Anion gap: Na+ – (Cl- + HCO3-) An elevated anion gap strongly suggests the presence of a metabolic acidosis.The normal anion gap varies with different assays, but is typically 4 to 12mmol/L. High anion metabolic acidosis.

Decontamination : The sooner decontamination is performed, the more effective it is at preventing poison absorption.

Severity of poisoning Time from ingestion Risk of intervention

Activated charcoal: 1g/kg usually given if patient presents within 1 hour of ingestion. can reduce absorption of many drugs: aspirin, para, phenobarbitone, digoxin, carbamazepine, theophylline, phenytoin. little value with: acids, alkalis, arsenic,, cyanide,, ethanol, ethylene glycol, heavy metals, hydrocarbons, iodide, iron, lithium, methanol.

Gastric lavage: should be only consider in patient present with toxic lethal dose in first one hour after exposure with protected airway. associated with visceral damage and aspiration. don’t give with corrosive, caustic, acids or petroleum ingestion.

Whole-bowel irrigation: using polyethylene glycol (golytely). suitable for conscious patients who have ingested tablets that don’t bind well to charcoal and can be identified on a plan radiograph. don’t use with charcoal 1-4 L/hr until patient passes clear fluid from bowel. Vomiting is common side effect.

Enhanced elimination techniques: the goal of enhanced elimination is to increase the clearance of the poison from the body , after it has been systemically absorbed .

Exposure of the eye to caustic chemicals and irritants requires immediate irrigation with large amounts of water or readily available fluids.

Antidote : Antidotes dramatically reduce morbidity and mortality in certain intoxications, but they are unavailable for most toxic agents and therefore are used in only about 1 percent of cases. They may prevent absorption, bind and neutralize poisons directly, antagonized-organ effects, or inhibit conversion to more toxic metabolites.

naloxone (opiates) digibind (digoxin) NaHCO3 (sodium channel blockers) high dose insulin euglycemic therapy (calcium channel blockers and beta- blockers)

Supportive care: Supportive care is the most important aspect of treatment . Supportive care for the poisoned patient is generally similar to that utilized for other critically ill patients, but certain issues are managed slightly differently.

Drug-associated agitated behavior : generally best treated with benzodiazepine administration, supplemented with high potency neuroleptics (eg,haloperidol) as needed.

Disposition : Patients who develop only mild toxicity and who have only a low predicted severity can be observed in the emergency department until they are asymptomatic. An observation period of four to six hours is usually adequate for this purpose.

Patients with moderate observed toxicity or those who are at risk for such on the basis of history or initial laboratory data should be admitted to an intermediate-care floor or an appropriate observation unit for continued monitoring and treatment.

Summary Common ED problem. Look for toxidrome ABC ECG

Paracetamol level Antidotes Supportive care