Transcript A patient with rat poison overdose

A patient with rodenticide
overdose
Dr WL Yip, AED, QMH
Case report
• F/44, housewife
• Found lying on the floor with decrease in
responsiveness
• Found an empty pack of ‘stilnox’ and an
empty can of beer lying around
• Argued with her husband one day ago
• Brought to AED ~0730
Examination
•
•
•
•
•
•
BP 120/60 P 100
Temp 35.70C
SaO2 98 with RR 22
Drowsy, with GCS E4 V5 M5
H’stix 4.7
ECG NSR 85/min
Further management
• Bld / Urine samples taken, with result
pending
• Admit medical due to full ‘O’ ward
• Patient woke up after 2 hours
• Admitted taken 20 tabs of stilnox and 1 can
of beer, and denied other drugs taken
• Pending seeing psychiatrist
Investigation…
• At 1400, found INR 7.7, PT 86.8, PTT 57.1
• Repeated… INR 7.6
• Further questioning… taken 1 pack of rat
poison bought over the counter few days
ago
• Contacted her husband…
• found a pack of rat poison ~5 days ago in
dust-bin at home
Other investigation results
• Hb 14.5
• Urine toxicology: BDZs, zolpidem
metabolites
• Otherwise unremarkable
Management
•
•
•
•
•
•
Clinically stable
No bleeding clinically
Transfusion of 4 units of FFP
Daily vitamin K1 10mg
INR 1.4 the next day
Seen by psychiatrist – depression
Psychiatric ward
• Form 123, transferred to PYNEH
psychiatric ward
• Continued daily oral vitamin K (10mg QD)
• INR finally back to 1.0 after 9 days
• Vitamin K was continued for 1 more week
afterwards
INR
Day 0
Day 1
Day 3
Day 6
Day 9
7.7
1.4
2.0
1.7
1.0
FFP
vit K1 (iv)
vit K (po)
Rodenticides
•
•
•
•
•
•
Warfarin / Superwarfarin
Arsenic
Cholecalciferol
Sodium monofluoroacetate
Strychine
Thallium
Warfarin / Superwarfarin
Warfarin / Superwarfarin
• Commonest in Hong Kong
• Anticoagulants
• prevent vitamin K from reducing to its
active form
• inhibit hepatic synthesis of coagulation
factors II, VII, IX, and X and the
anticoagulant proteins C and S
Vitamin K metabolism
Coagulation pathway
Initiation of coagulation
Superwarfarin
• Brodifacoum, bromadiolone
• Warfarin-resistance rats
• Clinical effects occur after depletion of the
mentioned factors (~3-4 days)
• Longer acting (weeks to months)
• Longer half-life (156 vs. 17 hrs)
• 100-folds more potent
Clinical features
• Rarely symptomatic, unless delayed
presentation
• Signs of bleeding
• Reported complications: Spontaneous intraabdominal hemorrhage, hematuria,
hematemesis, spontaneous
hemoperitoneum, intracerebral hemorrhage,
death
Investigation
• Clotting profile, repeated in 24-48 hours
• Drug level if available
• Pregnancy test for females of childbearing
age
Management
• GI decontamination
• Activated charcoal
• Specific treatment
– Vitamin K
– FFP
Vitamin K
•
•
•
•
•
15-120mg/d in divided doses
T1/2 = 6 hours
Antagonizes effects of warfarin
Indicated in INR>2
‘reverse’ anticoagulation, but not ‘prevent’ its
effect
• Anaphylactoid reaction if given iv
• Caution if already anticoagulated for other reasons
Superwarfarin poisoning
• Required higher daily dose and longer
duration (in months) of vitamin K
FFP
• Indicated if evidence of bleeding despite
use of vitamin K
比山埃毒百倍 警檢鼠藥器皿
毒鼠強奪命案枉死增至243人
16/09/2002
【中國組報道】南京驚天毒殺案後第二日，部分留醫者
家屬昨夜收到醫院發出病危通知，死亡人數可能進一步
攀升。而摻在受害者早餐中的毒藥，證實是毒性比山埃
還要強烈一百倍的老鼠藥「毒鼠強」；警方在案發地點
和盛園的水井旁發現殘留毒鼠強的器皿，一名案發後失
蹤的和盛園員工成重大疑犯。有消息稱，毒殺案死者人
數高達二百四十三名，而非官方公布的四十一人…
Tetramethylene Disulfotetramine
• C4H8N4O4S2
• GABA-antagonist, with CNS excitation
• Onset of symptoms several to 30 min (max.
13 hours)
• 6-12 mg is sufficient to cause death
• Proven to be toxic thru oral, inhalation and
dermal routes
• Rapid absorption with slow elimination
Mild toxicity
•
•
•
•
•
•
•
Headache
Dizziness
Fatigue
Anorexia
Nausea and vomiting
Numbness of lips
Listlessness
Severe toxicity
•
•
•
•
•
•
Loss of consciousness
Seizures
Foaming at the mouth
Urinary incontinence
Coma
Death from respiratory failure
Management
• Confirm its presence in vomitus, blood or
urine
• Symptomatic / supportive treatment
• Gastric lavage and activated charcoal
• Charcoal hemoperfusion
• Hemodialysis
?Antidote
• No specific antidote
• Vitamin B6 and DMPS (2,3-dimercapto-1sulphonate)
• Inhibit convulsion and reduce mortality in
animal studies
• No data a/v in human cases
Thank you