Spinal poisons

This is a powerpoint presentation of common spinal poisons encountered by physicians. Hope it would be helpful to you.

1. SPINAL POISONS DR. THOMAS JOHN

2. STRYCHNOS NUX VOMICA Strychnos nux vomica tree. Also known as dog button, poison nut. All parts of tree are toxic.

3. Toxicity - Seeds > Fruits > Leaves. Strychnine was used as rodenticide and for killing dogs(dog button). Medically used as tonics, stimulants etc. previously.

4. Strychnos nux vomica seeds Seeds are poisonous. Seeds are intensely bitter. Flat circular discs , slightly concave on one side and convex on other side. 2.5 cm in diameter. 6mmin thickness. Ash grey or light brown in colour , have a shiny surface covered with radiating silky fibres.

5. RIPE FRUIT OF STRYCHNINE Seeds obtained from ripe fruits are poisonous. Seeds are very hard , tough , and difficult to be reduced to fine particles . Bark , wood and leaves contain brucine.

6. ACTIVE PRINCIPLES Strychnine is a powerful alkaloid obtained from the seeds. Seeds contains strychnine and brucine . Seeds also contain glycoside , loganin . Strychnine is 10 to 20% more poisonous than brucine . Used as respiratory stimulant , as a rodenticide and for killing stray dogs .

7. Absorption and excretion ...... All mucus membrane absorb strychnine . Much is taken up by the liver and muscles to be either released again to blood stream or to be destroyed. Release of strychnine from the liver and muscles produces convulsions on second or third day of poisoning , after sedation is discontinued. About eighty 80% is oxidised mainly in liver . It is excreted slowly by the kidneys and traces in bile , milk and saliva. It may be found in cadaver in up to four years .

8. ACTION It inhibits inhibitory postsynaptic potentials in the spinal cord and prevents the effects of glycine . It releases the inhibitory effect on excitatory neurons, there by causing release excitation Action is particularly noted in anterior horn cells. It stimulates the cerebral cortex.

9. Symptoms onset..... If uncrushed seeds are swallowed ;no symptoms. If crushed seeds are taken ; symptoms are delayed for an hour or more. If the alkaloid is swallowed , symptoms occur within five to fifteen minutes.

10. SYMPTOMS ....... Bitter taste in mouth. Sense of uneasiness and restlessness , feeling of suffocation and great fear and difficulty in swallowing. Convulsions ; at first clonic , but eventually becomes tonic . Cyanosed face , anxious look , starring eyes , prominent eyeballs , dilated pupils . Contraction of jaws and facial muscles.

11. Symptoms continued...... Mouth is covered with froth , frequently blood stained, convulsion is most marked in antigravity muscles , so that the body typically arches in hyperextension [ Opisthonus ]

12. Trismus ( lockjaw), risus sardonicus (sardonic smile due to grimacing that results from facial muscle spasm) There may be frothing from the mouth. Pupils are usually dilated.

13. RISUS SARDONICUS

14. An important diagnostic feature is that there is complete muscle relaxation in between spasms and convulsions. Patient maintains a clear sensorium during and between the paralytic episodes.

15. COMPLICATIONS Hypoxia Hyperthermia Cardiac arrest Rhabdomyolysis Metabolic acidosis Acute renal failure Respiratory failure due to respiratory muscle paralysis- usual fatal event.

16. Fatal dose and treatment. one crushed seed (1-3gms). 30-60 mg of strychnine. One to two hours. Control of convulsions . With diazepam. Patient kept in dark room , free from noise and disturbance. Short acting barbiturates or sodium amytal . Stomach wash with dilute solution of potassium permanganate.

17. Physiological test. Injection of aqueous solution of suspected material into dorsal lymph sac of a frog , will produce tetanic convulsions in few minutes if strychnine is present.

18. Medico legal impotance . Suicide and homicide are rare Cattle poison. Arrow poison. Aphrodisiac.

19. Difference between strychnine poisoning and tetanus. Strychnine No h/o injury. Onset is sudden. All muscles of the body affected at a time. Tetanus h\o injury. Onset is gradual. All muscles not affeted at a time.

20. Strychnine has always had reputation of being the homicidal poisoner’s choice for murder. In reality, strychnine has been uncommonly employed in murder owing to various obvious reasons: bitter taste, dramatic nature of symptoms (that will always arouse suspicion of foul play), and easy detectability in body fluids and tissues.

21. Accidental poisoning can result in children who chew on the seeds out of curiosity while playing or foraging in the countryside. Previously, therapeutic misadventures used to be fairly common when strychnine was an approved constituent of various over-the-counter tonics and cathartics

22. DIAGNOSIS TLC gives reliable qualitative results on gastric aspirate, urine, blood or tissues. The best specimens are urine and gastric aspirate. HPLC provides accurate quantitative data. Blood levels in the range of 0.1-0.3 mg/100ml are generally lethal.

23. POISON HEMLOCK Conium maculatum ( botanical name) All parts of the plant are posonous. Coniine and gamma-coniceine are the toxins. Similar to nicotine.

24. The most serious effectoccurs at the neuromuscular junction where these alkaloidsact as non-depolarising blockers causing respiratory failuredue to flaccid paralysis. The second effect at the autonomic ganglia is nicotinic in nature resulting in salivation, mydriasis, and tachycardia, followed by bradycardia. Rarely rhabdomyolysis and ATN can occure.

25. CLINICAL FEATURES Nausea, vomiting and abdominal pain. Stimulant phase: tachycardia, tremors, sweating, mydriasis, convulsions. Depressive phase: bradycardia, ascending paralysis, and coma.

26. TREATMENT Aggressive GI decontamination. Benzodiazepines for convulsions. Respiratory support. Forced diuresis may prevent renal failure.

27. Hemlock was popular in ancient times as a means of execution. The most famous personality executed in this fashion was Socrates, who was condemned to death for his “crime” of introducing new divinities.

28. WATER HEMLOCH Cicuta maculata. All parts are poisons. Clinical features : nausea, vomiting and abdominal pain. Powerful convulsions leading to lethal status epilicticus.

29. TREATMENT Gastric decontamination. Control of convulsions. Hemodialysis. Aggressive supportive measures.

30. THANK YOU