Difference between revisions of "Chocolate Poisoning-Dog"

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Chocolate

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Introduction

Toxicity is due to the presence of methylxanthines such as theobromine and caffeine in chocolate ^[1]. The concentration of methylxanthines differs between products. For example the average methylxanthine content of milk chocolate is 2mg/g, while that of baking chocolate is 16mg/g. ^[1]. Concentrations ranging from of 100-250mg/kg of theobromine and 110-200mg/kg of caffeine have been reported to cause fatalities ^[1]. The consumption of more than 20mg/kg of total methylxanthines is considered the cut-off point in deciding whether or not to treat ^[1]. The concentration of methylxanthines differs between products ^[1] and therefore the number of grammes required to reach this threshold vary according to the product; in a 10kg dog 5000g of white chocolate provides the equivalent 20mg/kg dose of methylxanthines that 12-40g of plain chocolate, 83-117g of milk chocolate or 7-25g of cocoa powder does ^[1]. Methylxanthines are also present in beverages and foods other than chocolates ^[1].

Signalment

Dog that live indoors are more likely to have access to chocolate. Also puppies and dogs that scavenge are at a greater risk of eating food that is not intended for their consumption. Small breeds of dogs may reach the toxic level of methylxanthine concentration per body weight more easily ^[1].

Diagnosis

Clinical Signs

Chocolate poisoning results in CNS, gastrointestinal, cardiovascular and urological signs.^[1], ^[2]. These signs are observed quite quickly after ingestion of toxic amount of chocolate.^[2]

CNS: hyperexcitability, hyperactivity, ataxia initially can evolve into muscle tremors, clonic seizures and hyperthermia.^[1], ^[2]
Gastrointestinal: diarrhoea, emesis, haematemesis, colic.^[1], ^[2]
Cardiorespiratory: arrhythmias,infrequently bradycardia but usually tachycardia.^[1], ^[2]
Urological: polydypsia and polyuria may also be present ^[1]

Laboratory Tests

Diagnosis is usually on the basis of clinical signs and a known history of chocolate ingestion. The following laboratory tests are possible but not commonly used;

Detection of methylxanthines in bodily fluids such as plasma, urine and stomach contents ^[1].
Blood Glucose: Hypoglycaemia as a consequence of hyperactivity. not seen consistently with chocolate poisoning ^[1].
Urinalysis: Proteinuria, low specific gravity; not seen consistently with chocolate poisoning ^[1].

Other

ECG: rate and rhythm abnormalities

Pathology

The methylxanthines yield their effects through

Antagonism of Adenosine Receptors:^[1] this antagonism results in stimulation of the central nervous system, vasoconstriction and increase in heart rate ^[1] and also diureses ^[1]
Inhibition of Cyclic Nucleotide Phosphodiesterase:^[2] consequently there is an increase in cyclic AMP, which in turn leads to greater catecholamine release and their effects ^[1].
Modulation of Intracellular Calcium Concentrations:Enhanced uptake and decreased sequestration within the cell leads to amplification of intracellular calcium levels in cardiac and skeletal muscle, the net result of which is a positive inotropic effect on these muscles. ^[1].

Ventricular fibrillation, and other cardiac dysrhythmias are most frequently the ultimate cause of death.^[3], ^[4]

Treatment

Of dogs presenting with clinical signs
- Inital stabilisation of Cardiorespiratory System:
  - Tachycardia: beta-blockers, eg orally administered metoprolol at a dose of 0.5mg to 1mg per kg every 8 hours ^[1].
  - Premature Ventricluar Contractions: slow intravenous bolus of 2mg to 6mg per kg of lidocaine. Following this a constant rate infusion of 20ug to 70ug per kg per minute ^[1]
  - Bradycardia: Atropine at a dose of 0.01mg to 0.02mg per kg ^[1]

- Once stable treat as outlined below
Of dogs with a known history of recent chocolate ingestion but who have not yet developed clinical signs

Prognosis

References

↑ ^1.00 ^1.01 ^1.02 ^1.03 ^1.04 ^1.05 ^1.06 ^1.07 ^1.08 ^1.09 ^1.10 ^1.11 ^1.12 ^1.13 ^1.14 ^1.15 ^1.16 ^1.17 ^1.18 ^1.19 ^1.20 ^1.21 ^1.22 ^1.23 BSAVA Manual of Canine and Feline Emergency and Critical CareChapter 19, Second Edition,2007 Cite error: Invalid <ref> tag; name "multiples" defined multiple times with different content Cite error: Invalid <ref> tag; name "multiples" defined multiple times with different content Cite error: Invalid <ref> tag; name "multiples" defined multiple times with different content Cite error: Invalid <ref> tag; name "multiples" defined multiple times with different content Cite error: Invalid <ref> tag; name "multiples" defined multiple times with different content Cite error: Invalid <ref> tag; name "multiples" defined multiple times with different content Cite error: Invalid <ref> tag; name "multiples" defined multiple times with different content Cite error: Invalid <ref> tag; name "multiples" defined multiple times with different content Cite error: Invalid <ref> tag; name "multiples" defined multiple times with different content Cite error: Invalid <ref> tag; name "multiples" defined multiple times with different content Cite error: Invalid <ref> tag; name "multiples" defined multiple times with different content Cite error: Invalid <ref> tag; name "multiples" defined multiple times with different content Cite error: Invalid <ref> tag; name "multiples" defined multiple times with different content Cite error: Invalid <ref> tag; name "multiples" defined multiple times with different content Cite error: Invalid <ref> tag; name "multiples" defined multiple times with different content Cite error: Invalid <ref> tag; name "multiples" defined multiple times with different content Cite error: Invalid <ref> tag; name "multiples" defined multiple times with different content Cite error: Invalid <ref> tag; name "multiples" defined multiple times with different content Cite error: Invalid <ref> tag; name "multiples" defined multiple times with different content Cite error: Invalid <ref> tag; name "multiples" defined multiple times with different content Cite error: Invalid <ref> tag; name "multiples" defined multiple times with different content Cite error: Invalid <ref> tag; name "multiples" defined multiple times with different content Cite error: Invalid <ref> tag; name "multiples" defined multiple times with different content
↑ ^2.0 ^2.1 ^2.2 ^2.3 ^2.4 ^2.5 http://www.merckvetmanual.com/mvm/index.jsp?cfile=htm/bc/211104.htm. Cite error: Invalid <ref> tag; name "multiple" defined multiple times with different content Cite error: Invalid <ref> tag; name "multiple" defined multiple times with different content Cite error: Invalid <ref> tag; name "multiple" defined multiple times with different content Cite error: Invalid <ref> tag; name "multiple" defined multiple times with different content Cite error: Invalid <ref> tag; name "multiple" defined multiple times with different content
↑ Carson TL (2006) Methylxanthines. In: Small Animal Toxicology, ed. ME Peterson, PA Talcott, pp.845-852. Elsevier Saunders, St. Louis in BSAVA Manual of Canine and Feline Emergency Care Chapter 19, Second Edition,2007
↑ Holmgren P, Norden-Petterson L and Ahlner J (2004)Caffeine fatalaties: four case reports. Forensic Science International 139, 71-73 BSAVA Manual of Canine and Feline Emergency Care Second Edition,2007

[multiples-1] 1.00 ^1.01 ^1.02 ^1.03 ^1.04 ^1.05 ^1.06 ^1.07 ^1.08 ^1.09 ^1.10 ^1.11 ^1.12 ^1.13 ^1.14 ^1.15 ^1.16 ^1.17 ^1.18 ^1.19 ^1.20 ^1.21 ^1.22 ^1.23 BSAVA Manual of Canine and Feline Emergency and Critical CareChapter 19, Second Edition,2007 Cite error: Invalid <ref> tag; name "multiples" defined multiple times with different content Cite error: Invalid <ref> tag; name "multiples" defined multiple times with different content Cite error: Invalid <ref> tag; name "multiples" defined multiple times with different content Cite error: Invalid <ref> tag; name "multiples" defined multiple times with different content Cite error: Invalid <ref> tag; name "multiples" defined multiple times with different content Cite error: Invalid <ref> tag; name "multiples" defined multiple times with different content Cite error: Invalid <ref> tag; name "multiples" defined multiple times with different content Cite error: Invalid <ref> tag; name "multiples" defined multiple times with different content Cite error: Invalid <ref> tag; name "multiples" defined multiple times with different content Cite error: Invalid <ref> tag; name "multiples" defined multiple times with different content Cite error: Invalid <ref> tag; name "multiples" defined multiple times with different content Cite error: Invalid <ref> tag; name "multiples" defined multiple times with different content Cite error: Invalid <ref> tag; name "multiples" defined multiple times with different content Cite error: Invalid <ref> tag; name "multiples" defined multiple times with different content Cite error: Invalid <ref> tag; name "multiples" defined multiple times with different content Cite error: Invalid <ref> tag; name "multiples" defined multiple times with different content Cite error: Invalid <ref> tag; name "multiples" defined multiple times with different content Cite error: Invalid <ref> tag; name "multiples" defined multiple times with different content Cite error: Invalid <ref> tag; name "multiples" defined multiple times with different content Cite error: Invalid <ref> tag; name "multiples" defined multiple times with different content Cite error: Invalid <ref> tag; name "multiples" defined multiple times with different content Cite error: Invalid <ref> tag; name "multiples" defined multiple times with different content Cite error: Invalid <ref> tag; name "multiples" defined multiple times with different content

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[3] Carson TL (2006) Methylxanthines. In: Small Animal Toxicology, ed. ME Peterson, PA Talcott, pp.845-852. Elsevier Saunders, St. Louis in BSAVA Manual of Canine and Feline Emergency Care Chapter 19, Second Edition,2007

[4] Holmgren P, Norden-Petterson L and Ahlner J (2004)Caffeine fatalaties: four case reports. Forensic Science International 139, 71-73 BSAVA Manual of Canine and Feline Emergency Care Second Edition,2007

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 "[[File:Chocolate.jpg|thumb|Chocolate]]"
 ==Introduction==
-Toxicity is due to the presence of methylxanthines such as theobromine and caffeine in chocolate <ref name="multiples"> '''BSAVA Manual of Canine and Feline Emergency and Critical Care'''Chapter 19, Second Edition,2007 </ref>. The concentration of methylxanthines differs between products. For example the average methylxanthine content of milk chocolate is 2mg/g, while that of baking chocolate is 16mg/g. <ref name=multiples> Tilley, Smith'''The 5-Minute Veterinary Consult Canine and Feline''' (Second Edition), ''Lippencott, Williams and Wilkins''</ref>. Concentrations ranging from of 100-250mg/kg of theobromine and 110-200mg/kg of caffeine have been reported to cause fatalities <ref name="multiples"> '''BSAVA Manual of Canine and Feline Emergency and Critical Care'''Chapter 19, Second Edition,2007 </ref>.  The consumption of more than 20mg/kg of total methylxanthines is considered the cut-off point in deciding whether or not to treat <ref name="multiples"> '''Dietary intoxications, Chocolate (Theobromine and Caffeine)''', Warman SM, p253,''BSAVA Congress 2007 Scientific Proceedings, Veterinary Programme'' </ref>. The number of grammes required to reach this threshold vary according to the product; in a 10kg dog 5000g of white chocolate provides the equivalent 20mg/kg dose of methylxanthines that 12-40g of plain chocolate, 83-117g of milk chocolate or 7-25g of cocoa powder does <ref name="multiples"> '''Dietary intoxications, Chocolate (Theobromine and Caffeine)''', Warman SM, p253,''BSAVA Congress 2007 Scientific Proceedings, Veterinary Programme'' </ref>.
+Toxicity is due to the presence of methylxanthines such as theobromine and caffeine in chocolate <ref name="multiples"> '''BSAVA Manual of Canine and Feline Emergency and Critical Care'''Chapter 19, Second Edition,2007 </ref>. The concentration of methylxanthines differs between products. For example the average methylxanthine content of milk chocolate is 2mg/g, while that of baking chocolate is 16mg/g. <ref name=multiples> Tilley, Smith'''The 5-Minute Veterinary Consult Canine and Feline''' (Second Edition), ''Lippencott, Williams and Wilkins''</ref>. Concentrations ranging from of 100-250mg/kg of theobromine and 110-200mg/kg of caffeine have been reported to cause fatalities <ref name="multiples"> '''BSAVA Manual of Canine and Feline Emergency and Critical Care'''Chapter 19, Second Edition,2007 </ref>.  The consumption of more than 20mg/kg of total methylxanthines is considered the cut-off point in deciding whether or not to treat <ref name="multiples"> '''Dietary intoxications, Chocolate (Theobromine and Caffeine)''', Warman SM, p253,''BSAVA Congress 2007 Scientific Proceedings, Veterinary Programme'' </ref>. The concentration of methylxanthines differs between products <ref name=multiples> Tilley, Smith'''The 5-Minute Veterinary Consult Canine and Feline''' (Second Edition), ''Lippencott, Williams and Wilkins''</ref> and therefore the number of grammes required to reach this threshold vary according to the product; in a 10kg dog 5000g of white chocolate provides the equivalent 20mg/kg dose of methylxanthines that 12-40g of plain chocolate, 83-117g of milk chocolate or 7-25g of cocoa powder does <ref name="multiples"> '''Dietary intoxications, Chocolate (Theobromine and Caffeine)''', Warman SM, p253,''BSAVA Congress 2007 Scientific Proceedings, Veterinary Programme'' </ref>.
 Methylxanthines are also present in beverages and foods other than chocolates <ref name="multiples"> '''BSAVA Manual of Canine and Feline Emergency and Critical Care'''Chapter 19, Second Edition,2007 </ref>.