Diagnosis & Management of Insecticide Poisoning Winai Wananukul, M.D. Ramathibodi Poison Center & Department of Medicine Ramathibodi Hospital

Winai Wananukul, Ramathibodi Poison Center Epidemiology of Toxic Exposure (May April 2001)

Winai Wananukul, Ramathibodi Poison Center Classification of Pesticide Exposure

Winai Wananukul, Ramathibodi Poison Center Classification of Insecticide Exposure

Winai Wananukul, Ramathibodi Poison Center Classification of Herbicide Exposure

Winai Wananukul, Ramathibodi Poison Center Classification of Rodenticide Exposure

Winai Wananukul, Ramathibodi Poison Center Ratio of Exposure with and without clinical manifestation of poisoning at the time consult to the Poison Center

Winai Wananukul, Ramathibodi Poison Center Medical Outcome of the Risk Group

Winai Wananukul, Ramathibodi Poison Center Medical Outcome of the Poisoned Group

Winai Wananukul, Ramathibodi Poison Center Medical Outcome of Selected Toxic Exposure

Winai Wananukul, Ramathibodi Poison Center Survival & Death Rate of Selected Pesticide Exposure (from high to low mortality rate) 61.3% 42.3% 22.9%20.0% 4.2%2.5%1.6%

Organophosphate and Carbamate Poisoning

Winai Wananukul, Ramathibodi Poison Center What is Acute Organophosphate & Carbamate Poisoning ? 4 State of Acetylcholine Excess 4 It is a combination of –Muscarinic receptor –Nicotinic receptor –CNS (unspecified)

Winai Wananukul, Ramathibodi Poison Center Organophosphate VS. Carbamate Poisoning 4 Reversible vs. Irreversible Inhibition –Reversible vs. Irreversible clinical poisoning –Time of clinical course 4 Blood brain barrier penetration –CNS symptoms (after exclude hypoxic effects)

Winai Wananukul, Ramathibodi Poison Center Clinical course after acute poisoning 4 Cholinergic Excess 4 Others (than cholinergic excess) –Intermediate syndrome –Delayed neuropathy –Arrthymias

Winai Wananukul, Ramathibodi Poison Center Diagnosis of Organophosphate or Carbamate Poisoning: 4 Clinical Diagnosis 4 Laboratory –Red cell cholinesterase –Plasma (Pseudo, Butyryl (Bu)) cholinesterase

Winai Wananukul, Ramathibodi Poison Center Management of OP & CB Poisoning 4 Supportive Care –Vital signs –Respiration: secretion block and airway obstruction respiratory motor weakness –Seizure 4 Specific Treatment

Airway Skin Parenteral GI. Circulation Tissues & Organs Ion Trapping RAC. Decontamination IncreaseElimination Antidotes Hemodialysis, Hemoperfusion

TOXIC ANTIDOTES

Muscarinic Effects Heart rate SweatingSecretionPupils Atropine

AChE Inhibitions NicotinicMuscarinic 2 PAM

Nicotinic Effects Motor Power + (Muscarinic Effects) 2 PAM

Winai Wananukul, Ramathibodi Poison Center Intermediate Syndrome 4 Develop only after some acute organophosphate poisoning 4 Mechanism: unknown –not directly relate to acetylcholine excess 4 Clinical Manifestation: –Proximal muscle weakness –Bulbar palsy

Winai Wananukul, Ramathibodi Poison Center Intermediate Syndrome 4 Spontaneous recover in 2 -3 weeks after develop 4 Treatment –Supportive care, especially respiratory care 4 Note: this condition must be differentiated from “Aged Acetylcholinesterase”

Winai Wananukul, Ramathibodi Poison Center Chronic Organophosphate Poisoning 4 Clinical Features: –Delay polyneuropathy –Neuropsychiatric disorder 4 Diagnosis –Clinical diagnosis, by suspicious & exclusion 4 Investigation –?? Plasmacholinesterase 4 Treatment –Not established

Winai Wananukul, Ramathibodi Poison Center ชายอายุ 31 ปี อาชีพชาวนา จังหวัดลพบุรี 1/2 ชั่วโมงก่อนกินยาฆ่าแมลงชื่อ “Egodan” ประมาณ ½ ขวด หลังจากกินมี อาการชักเกร็งตลอดเวลา ญาติจึงนำส่งรพ. ที่ ER ตรวจร่างกาย :HR 140/min, BP 160/110, RR 22/min ผู้ป่วยมี generalized tonic and clonic seizure ตลอดเวลา ได้ ET tube intubation ให้ iv fluid แล้วฉีด diazepam

Winai Wananukul, Ramathibodi Poison Center ชายอายุ 31 ปี อาชีพชาวนา จังหวัดลพบุรี ตรวจร่างกายเพิ่มเติม :unconscious Pupil 4 mm, react to light bilateral Lung : clear Abdomen : soft, normal bowel sound Neurological signs: no stiff neck, motor power grossly intact, absent of Babinsk’s sign.

Organochlorine Poisoning

Winai Wananukul, Ramathibodi Poison Center Classification of Organochlorine Dichlorodiphenylethanes DDTMethoxychlorHexachlorocyclohexane LindaneCyclodienes AldrinChlordane Dieldrin EndrinEndosulphanHepatochlor Chlordecone (kepone) Mirex

Winai Wananukul, Ramathibodi Poison Center Acute Organochlorine Poisoning 4 Prodomal symptoms: –tremor, ataxia, quick involuntary jerk (myoclonus) –dizziness, confusion –Paresthesia of month, –nausea, vomiting

Winai Wananukul, Ramathibodi Poison Center Acute Organochlorine Poisoning 4 The typical presentation: Status epilepticus 4 Followed by: –Respiratory failure –Cardiac arrhythmias –Rhabdomyolysis & acute renal failure

Winai Wananukul, Ramathibodi Poison Center Acute Organochlorine Poisoning 4 Treatment: –Control seizure as the same way as “Status epilepticus” Benzodiazepines Phenobarbital Phenytoin –Prevent complications

Winai Wananukul, Ramathibodi Poison Center Diagnosis of Organocholine Poisoning 4 Clinical Diagnosis –History of exposure –Clinical features of repeated seizure 4 Laboratory Test –Plasma level –Subcutaneous fat level

Winai Wananukul, Ramathibodi Poison Center Subacute Organochlorine Poisoning 4 Hyperexcitability stage: –Tachycardia –Tremor –Hyperreflexia 4 Treatment –Symptomatic Px: Anxiolytic –Enhance Elimination : Cholestyramine

Winai Wananukul, Ramathibodi Poison Center Chronic Organochlorine Poisoning –Organochlorine insecticides interfere with endocrine and reproductive systems. –People who working with the insecticides have low sperm count and motility, infertility and abortion. –The insecticides have also been reported to be carcinogenic to animals.

Pyrethroid Poisoning

Winai Wananukul, Ramathibodi Poison Center Classification of Pyrethrins & Pyrethroids Pyrethrins Cinerin ICinerin IIJustmolin IJusmolin II Pyrethrin IPyrethrin IIPyrethrum extract Type I Pyrethroids Allethrin BioallethrinCismethrinKadethrin PermethrinPhenothrinResmethrinTetramethrin Type II Pyrethroids CyhalothrinCypermethrinCyphenothrinDeltamethrin Fenpropenthrin FenvalerateFluvalinate

Winai Wananukul, Ramathibodi Poison Center Pyrethroids Exposure 4 Direct Toxic 4 Hypersensitivity –Allergic rhinitis –Bronchitis –Bronchial asthma –Anaphylactic shock 4 Local Irritation –Contact dermatitis –Corneal abrasion

Winai Wananukul, Ramathibodi Poison Center Pyrethroid Poisoning: Insect The type I syndrome (caused by type I pyrethroids): fine tremor reflex hyperexcitability sympathetic activation The type II syndrome (caused by type II pyrethroids): salivation coarse tremor choreoathetosia reflex hyperexcitability sympathetic activation, and seizure

Winai Wananukul, Ramathibodi Poison Center Pyrethroid Poisoning: Human Usually mild Common: nausea and vomiting after ingestion of pyrethroids. Sever Cases: drowsiness, seizure and coma ( In patient exposed to large amount of pyrethroids, especially the product used in agriculture in higher concentration) Death from pyrethroid poisoning is rare.

Winai Wananukul, Ramathibodi Poison Center Diagnosis of Pyrethroid Poisoning 4 Clinical Diagnosis 4 Laboratory Test –None

Winai Wananukul, Ramathibodi Poison Center Management of Pyrethroid Poisoning 4 Hypersensitivity: –Adrenaline –Corticosteroids –Bronchodilators –Antihistamine 4 Direct Toxic: –Supportive treatment