Veterinary Clinical Medicine-I (General and Systemic)

TOXICOLOGICAL EMERGENCIES

• Amitraz:It affects the peripheral alpha1 an d alpha2 adrenergic site in CNS system
• Toxicity: Oral or dermal route
• History: Ingestion, vomition, polyurea, ataxia, depression that may progress to coma.
• Signs: Hypotension, hypothermia, mydriasis, bradycardia, hypopesistalsis, vomiting, diarrhea, polyurea, ataxia, sedation, disprientation, coma.
• Note: Atropine sulpate contraindicated

Treatment

• Spontaneous recovery in mildly affected animals.  In comatosed animal, attempt to remove by gastric lavage.
  • Administer activated charcoal 2-5 g/kg b.wt PO (in slurry), 1g / 5 ml, repeat after 3-4 hrs.
  • Cathartic: osmotic or saline cathartic after 30 min of administration of charcoal.
  • Sorbitol – 4g / kg b.wt PO as 7% preparation
  • Mix 200 – 500 mg of magnesium sulfate in water and give at the rate of 5ml – 10ml / kg b.wt. PO.
  • Yohimbine – 0.11 mg/kg b.wt. slow i/v competitively inhibit alpha2 receptor and removes depression, hypotension and bradycardia.
  • Atipamazole – 50 mg/kg b.wt i/m q 3-4 hrs. can also be combined with yohimbine at dose rate of 0.1 mg/kg b.wt 8 hrs.

Organophosphorous Compounds and Carbamate Poisoning

• Clinical Signs
  • Muscarinic signs – SLUD, bradycardia
  • Nicotinic signs – muscle tremor, twitching, paresis, paralysis
  • Depression, seizures
• Treatment
  • Dermal exposure – wash
  • Ingestion – emesis, lavage
  • Death due to cardiac arrhythmia, dyspnoea caused by excessive pulmonary secretion.
  • Atropine – 0.1 – 0.5 mg/kg .wt, ¼^th i/v q 6 hrs (if muscarnic signs returns) and wait 5 min ¾^th s/c or i/m. Atropine counteracts only muscarinic sings.
  • Antidote – 2 pralidoxine chloride (2PAM).
    • Small animals – 20 mg/kg .wt twice daily i/v slowly, i/m q 8-12 hrs
    • Horse - 2g slow i/v TID
    • Cattle - 20-50 mg/kg b.wt i/v

Organochlorine Poisoning

• Clinical Signs
  • Nervous system – severity of clinical signs not corretated with prognosis.
    • Earlier:- Salivation, nausea, vomiting, nervousness, tremors, hyperexitability, incordination.
    • Advanced:- clonic, tonic spasms, seizures, opisthotonus, paddling, champing of jaws.
  • In cattle:- abnormal posture, lick excessively, walk backwards.
• Treatment
  • Dermal - wash
  • Ingestion - Activated charcoal, phenobarbitone, pentobarbitone, diazepam, propofol.
  • Supportive therapy and place the animal in comfortable place.

Pyrethrin Poisoning

• Clinical Signs
  • Mild:- Mild hypersalivation, ear twitching, depression, vomiting, diarrhea.
  • Moderate:- hyperaesthesia, incoordination, muscle tremor
  • Severe:- seizure and death 
  • Emergic reaction: pruritis, hyperaemia, shock, urticaria, death (rare)
• Treatment
  • Topical decontamination
    • Detergent bath (hand wash)
    • Adverse reactions are mild and self limiting
    • Maintenance of body temperature is critical.
  • Tremous:- Diazepam – 0.5 mg/kg b.wt i/v to effect
  • Phenobarbitone – 2-4 mg/kg b.wt i/v to effect
  • Atropine sulfate contraindicated

Ivermectin Poisoning

• Clinical Signs
  • Ataxia, vocalization, disorientation, aggression, blindness, head pressing, loss of menace reflex, incomplete PLR.
  • Severe cases: Bradycardia, hypothermia, respiratory depression, multifocal impairment of thalamus, coma, death.
• Treatment
  • Symptomatic and supportive care
  • CNS depression may last for a week, institute nutritional care.
  • Affected animal remain recumbent for long period. Physiotherapy with frequent turning and nursing care.

Rodenticide or Anticoagulant Poisoning

• Clinical Signs
  • Bleeding through nose, bowel, gums, wounds
  • Pale mucosa, depression, lethargic, haematuria, melena
  • Lameness, haemrrhage in cavity, hypovolemic shock
• Treatment
  • Phythomenodione – 2.5 – 5 mg / kg b.wt P/O, i/v, i/m, s/c, 5 days – 6 weeks
  • Bioavailability enhanced by fat.
  • Fresh blood or plasma transfusion. Anaphylactic reaction may occur during vitamin K administration.

Cyanide Poisoning

• Sodium nitrate - 22 mg / kg b.wt i/v
• Sodium thiosulfate - 660 mg/kg .wt i/v

Nitrate Poisoning

• Methylene blue - 4-15 mg/kg b.wt i/v as 1% solution
• Repeat dose at 6-8 hrs.