Approach to a poisoned child

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Guide –Dr Jyoti Singh

What is a poison?

▪ In common usage - poisons are chemicals or chemical products that are distinctly harmful to human

▪ More precisely - a poison is a foreign chemical (xenobiotic) that is capable of producing a harmful effect on a biologic system

Most common Pediatric Exposure Cosmetics and personal care products

(13%) Cleaning substances (10%) Analgesics (7.8%) Foreign Bodies (7.4%) Topicals (7.4%) Cold and Cough Preparations (5.5%) Plants (4.6%) Pesticides (4.1%)

May be difficult because of non-specific symptoms

High index of suspicion - especially occult poisoning▪ history may be unreliable▪ look for corroborative history - missing pills,

empty container

Course that a poison runs (toxidromes) ! - may help

Toxicology screening - helpful only in a few

▪ It is the association of several clinically recognizable features, signs, symptoms, phenomena or characteristics which often occur together, so that the presence of one feature alerts the physician to the presence of the others.

S alivation *D iaphoresis/diarrhea

L acrimation *U rinationU rination *M iosisD efecation *B

radycardia/bronchospasmG I secrestion/upset *E mesisE mesis *L acrimation excess

*S alivation excess

Hot as a hare

Dry as a bone

Red as a beet

Mad as a hatter

Blind as a bat

bowel, bladder

lose their tone, &

heart runs alone

Hot as a hare

Dry as a bone

Red as a beet

Mad as a hatter

Blind as a bat

bowel , bladder lose their tone, &

heart runs alone

Hot as a hare

Dry as a bone

Red as a beet

Mad as a hatter

Blind as a bat

bowel , bladder

lose their tone,

&heart runs alone

disorientation Amphetamine

hallucinations Cocaine

Hallucinogenic hyperactive bowel Pseudoephedrine

panic PhencyclidineBenzodiazepenes

seizure Ephedrine

Toxidrome Hypertension

Tachycardia

Tachypnea

disorientation Amphetamine

hallucinations Cocaine

Hallucinogenic hyperactive bowel Pseudoephedrine

panic PhencyclidineBenzodiazepenes

seizure Ephedrine

Toxidrome Hypertension

Tachycardia

Tachypnea

disorientation Amphetamine

hallucinations Cocaine

Hallucinogenic hyperactive bowel Pseudoephedrine

panic PhencyclidineBenzodiazepenes

seizure Ephedrine

Toxidrome Hypertension

Tachycardia

Tachypnea

disorientation Amphetamine

hallucinations Cocaine

Hallucinogenic hyperactive bowel Pseudoephedrine

panic PhencyclidineBenzodiazepenes

seizure Ephedrine

Toxidrome Hypertension

Tachycardia

Tachypnea

Very diverse and varied - depends on the poison

Clinical examination should be focused on the possible manifestations of common poisons in the geographical area

Skin and mucosal damage Neurotoxic manifestations Cardiovascular manifestations Metabolic consequences Eye manifestations Hepatic , renal dysfunction Multiorgan dysfunction

Respiratory

Airway protection

Respiratory failure

Cardiovascular

Hypotension despite fluid challenge

Heart block, arrhythmias, QTc prolongation as in TCA

Neurologic▪ Low GCS ▪ Seizures

Metabolic▪ Hypoglycaemia▪ Significant electrolyte abnormalities▪ metabolic acidosis▪ Hepatic failure▪ Coagulopathy with bleeding

ASSESSMENT & THERAPY should proceed in parallel

Treat the patient, not the poisonAssess

General appearance Work of breathing Circulation

ABCDs IV access and monitorsHigh Suspicion

Directed exam (after ABCs)

mental status vital signs pupillary size skin signs

Airway - ensure clear airway, clear secretions, check for cough/gag

Breathing - check oxygenation, supplemental O2, breathing pattern & adequacy

Circulation - heart rate, rhythm, blood pressure

Neurologic - GCS, seizures, agitation, spasms, pupils, autonomic dysfunction

Miscellaneous - odour, temperature, pallor, cyanosis, jaundice

Abdomen - rigidity, bleeding, urine output

Cyanosis methemoglobinemia secondary to

nitrites, nitrates, phenacetin, benzocaine-refractory tp o2

Red flush carbon monoxide, cyanide, boric acid,

anticholinergics

Joundice – c cl4. paracetamol

Dry anticholinergics

Salivation organophosphates, carbamates

Oral lesions corrosives, paraquat

Lacrimation caustics, organophosphates, irritant

gases

Anti-histamine Anti-depressant Anticholinergics (atropine) Sympathomimetics

amphetamine, cocaine, PCP

Cholinergics, Clonidine Opiates, Organophosphates Phenothiazine, Pilocarpine Sedatives (barbiturates, ethanol)

Alcohol PCP / marijuana LSD Anticholinergics Sympathomimet

ics Phenothiazines Cocaine Heroin heavy metals

Coma alcohols, anticholinergics, sedative hypnotics, opioids, carbon monoxide, TCAs, salicylates, organophosphates

Weakness/paralysis organophosphates, carbamates, heavy

metals

Atropine Salicylates Theophylline Cocaine TCA

Ethanol Narcotics Carbon

monoxide Clonidine

Bradycardia digitalis, sedative hypnotics, beta

blockers, opioids

Tachycardia anticholinergics, sympathomimetics,

amphetamines, alcohol, aspirin, theophylline, cocaine, TCAs

Arrythmias anticholinergics, TCAs, organophosphates,

digoxin, phenothiazines, beta blockers, carbon monoxide, cyanide

OTC cold remedies

Amphetamine PCP TCA Cocaine Diet pills

Calcium channel blockers

Carbon monoxide Cyanide Iron Narcotics Anti-hypertensives Met-hemoglobin

Hypoglycemia Oral hypoglycemic

agents Beta-blockers Insulin Ethanol Salicylates

Alcohol Narcotics Clonidine Sedatives

Of limited value

Paracetamol levels, salicylate levels, alcohol, Red cell/pseudocholinesterase, anti-epileptic drug levels

Urinary drug screen - opiates, barbiturates, benzodiazepines, amphetamines, cocaine

Anion gap & Osmolal gap

Increased anion gap (Normal 12 ± 4 mEq/L)▪ Ethylene glycol▪ Methanol▪ Salicylate poisoning

Increased osmolal gap (Normal 5 ± 7 m osmol/kg)▪ Ethylene glycol ▪ Methanol ▪ Acetone, ethanol, isopropyl alcohol,

propylene glycol

Electrolytes▪ Hypokalemia▪ Isuline ,oral hypoglysemics ▪ Diuretics, Methyl xanthine, Toluene

▪ Hyperkalemia▪ Digoxin▪ Beta-blocker

Liver function tests▪ Acetaminophen, Ethanol, Carbon tetrachloride

Renal function tests▪ Ethylene glycol, NSAIDS

ECGDigoxin toxicityTCA overdose - sinus tachycardia, QT prolongation,

increased QRSBeta-blockers - conduction abnormalities

Imaging

. CXR- hydrocarbon ingestion .Abdominal X-ray-- iron ingestion & radioopaque

ingestion. .Oesophagoscopy -for caustic ingestion.

. Abdominal usg- recently been used as a means of identifying presence of pharmaceutical material in GIT.

Opiates Cocaine metabolite Amphetamine Benzodiazepines Barbiturates

* No urine screen can confirm intoxication, only exposure

Reduce absorption of the toxin

Enhance elimination

Neutralise toxin

Removal from surface skin & eye

Emesis induction

Gastric lavage

Activated charcoal administration & cathartics

Dilution - milk/other drinks for corrosives

Whole bowel irrigation

Endoscopic or surgical removal of ingested chemical

Skin decontamination

▪ Important aspect – not to be neglected

▪ Remove contaminated clothing

▪Wash with soap and water (soaps containing 30% ethanol advocated)

▪However, no evidence for benefit even in OP poisoning

Gastric decontamination

▪ Forced emesis if patient is awake▪Gastric lavage▪ Activated charcoal 25 gm 2 hourly▪ Sorbitol as cathartic

Gastric lavage

▪ Gastric lavage decreases absorption by 42% if done 20 min and by 16% if performed at 60 min

▪ Performed by first aspirating the stomach and then repetitively instilling & aspirating fluid

▪ Left lateral position better - delays spont. absorption

▪ No evidence that larger tube better▪ Simplest, quickest & least expensive way ▪ Choice of fluid is tap water - 5-10 ml/kg

Gastric lavage

▪ Preferrably done on awake patients

▪ Presence of an ET tube does not preclude aspiration, though preferred if GCS is low

▪ No human studies in OP poisoning showing benefit of gastric lavage

Single dose activated charcoal 0.5-1 gm/kg, adolescents 50-100 grams

PO; maximum dose 100 grams More benefit if administered within 1

hour of ingestion, but still good for poison which slows gastric motility (anticholinergic, opiates, salicylates)

Strongly consider for acetaminophen overdose > 4 hours

P – Pesticides, petroleum distillates, unprotected airway

H – Hydrocarbons, heavy metals, > 1h delay in administration

A – Acids, alkali, alcohol, altered level of consciousness, aspiration risk

I – Iron, ileus, intestinal obstructionL – Lithium, lack of gag reflexS – seizures

Nonabsorbable, isotonic polyethylene glycol

Toxins “pushed” through GI tract; prevents absorption

Concentration gradient created by this allows absorbed toxin to diffuse back into GI tract

Used where toxins NOT absorbed by charcoal

Recommended for: Iron tablets Lead paint chips Theophylline Crack vials/packets Button batteries Sustained release calcium channel

blockers

Bowel perforation Bowel obstruction Clinically significant gastrointestinal

hemorrhage Ileus Unprotected or compromised airway Hemodynamic instability Uncontrollable intractable vomiting

Methods▪ Keeping a good urine output 150-200 ml/hr▪ Alkalinisation of urine - clinical efficacy accepted for salicylate & phenobarbital poisoning▪ Extracorporeal removal▪Hemodialysis - Barbiturates, Salicylates, Acetaminophen, Valproate, Alcohols, Glycols▪Hemoperfusion - theophylline, digitalis, lipid soluble drugs

Plasmapheresis Works very well with highly protein

(albumin) bound drugs Not a routine methodology, but has

been used to remove theophylline and digoxin/ digibind complexes

Exchange transfusion Use in smaller infants where

vascular access for extracorporeal techniques can’t be done

Renal failure. Congestive heart failure (relative). Acute lung injury. Persistent CNS disturbance. Severe acid-base or electrolyte

imbalance, despite appropriate treatment.

Hepatic compromise with coagulopathy.

Salicylate concentration (acute) >100 mg/dL.

Acetaminophen N-acetyl cysteine Anti-cholinergics Physostigmine Benzodiazepenes Flumazenil Ca channel blockers Glucagon, Insulin + dextrose, Calcium Carbamate Atropine Cyanide Thiosulphate, nitrate Digoxin Digoxin antibodies INAH Pyridoxine Methanol Ethanol, Fomepizole Glycol Ethanol, Fomepizole Opioid Naloxone Oral hypoglycaemics Glucose Organophosphate Atropine, PAM Warfarin(rat kill poison) Vitamin K

Iron Desferroxamine Copper Penicillamine, Dimercaprol, CaEDTA Lead CaEDTA, Dimercaprol (BAL) Mercury DMPS, DMSA, BAL Arsenic BAL & derivatives Antimony BAL & derivatives

Calcium channel blockers: bradycardia and hypotension; 1 - 10 mg tablet of nifedipine

Camphor: respiratory depression and seizures; 15 mL of Vicks vapo-rub (700 mg of camphor)

Clonidine: severe bradycardia; 0.1 mg

Tricyclic antidepressants: cardiovascular and CNS toxicity; 10-20mg/kg

Opioids: CNS and respiratory depression; 2.5 mg of hydrocodone.

Lomotil: anticholinergic overdose (tachycardia, seizures, coma); ½ tablet

Salicylates: cerebral edema, acidosis, coma; ½ teaspoon of wintergreen fatal

Sulfonylureas: severe hypoglycemia; 1 tablet

Toxic alcohols: cardiac and CNS depression; 2.9mL of 95% ethylene glycol has been fatal

National Poisons Information Centre (NPIC)

Department of  PharmacologyAll India Institute of Medical SciencesNew Delhi, IndiaTel. No.: 26589391, 26593677, Fax: 26850691, 26862663Email: npicaiims@hotmail.com provides round-the-clock, 7 days-a-

week, 365 days service on telephone.

Poisoning a common problem in our country

A high index of suspicion required to diagnose

Know common toxidrome & antidotes

Charcoal is only given if likely to benefit

Patients receiving decontamination must have airway protection

Don’t panic and follow a plan of actionDecreasing absorptionEnhancing eliminationNeutralising toxins

Avoid potentially harmful Rxs - risk vs benefit