31 – Household Hazards Flashcards
(37 cards)
1
Q
Ethylene glycol
A
- Major component of antifreeze
- All species susceptible (most in dogs and cats)
o Cats more vulnerable
2
Q
Ethylene glycol: exposure scenario
A
- Sweet taste previously
- Seasonal? (not necessarily)
- Leakage from machinery
- Left in garage with access
3
Q
Ethylene glycol calculation question: Antifreeze brand you use contains 50% ethylene glycol. How much would a 10lb cat have to drink to receive a lethal exposure? (cat LD: 1.5mL/kg BW)
A
- 10lbs BW = 4.5kg BW
- 4.5kg x 1.5mL/kg BW = 6.75mL
- Account for dilution: 13.5mL (less than 1 tablespoon)
4
Q
Ethylene glycol: target organ
A
- KIDNEYS
- Secondary: CNS, CV system
5
Q
Ethylene glycol: mechanism of toxicity
A
- Will resemble ethanol poisoning to begin
- Bioactivation reaction in liver
- Different rate limiting steps
o EG to glycolaldehyde via alcohol dehydrogenase
o Glycolic acid to glyoxylic acid via aldehyde dehydrogenase - Oxalic acid: sequesters calcium
- Urinary filtrate: precipitation of calcium oxalate crystals=obstructive nephropathy
6
Q
*Ethylene glycol: phase 1 clinical features
A
- Due to UNMETABOLIZED EG
- 30mins to 12 hrs
- CNS depression: resembles ethanol intoxication
- Nausea, vomiting, depression, ataxia, hypothermia, polyuria
- With worsening CNS depression, animals drink less
7
Q
*Ethylene glycol: phase 2 clinical features
A
- Due to EG metabolites
- Species differences: quicker in cats
- Severe metabolic acidosis: myocardial depression, tachypnea, tachycardia
- Severe lethargy progressing to coma
- Oliguria progressing to anuria
8
Q
Ethylene glycol: clinical pathology
A
- HYPOCALCEMIA, hyperphosphatemia
- Azotemia (only with 50% impaired)
- Increased osmolal gap
- High anion gap, titration type METABOLIC ACIDOSIS
o Due to accumulation of glyoxylic acid and decreased GFR
9
Q
Ethylene glycol: urinalysis
A
- Isosthenuria or hyposthenuria
- Aciduria
- Cellular debris from necrosis
- HALLMARK: CALCIUM OXALATE CRYSTALS
10
Q
*Ethylene glycol: histologic pathology
A
- ACUTE TUBULAR NECROSIS WITH CALCIUM OXALATE CRYSTALS
o Kidney
o Birefringent crystals under polarized light
o Renal tubular epithelial lesions
11
Q
Ethylene glycol: management
A
- Likely not possible to decontamination or induce emesis
- ANTIDOTES
- Symptomatic and supportive care for kidneys: fluids, monitor urine output, correct acidosis
- If available: dialysis is very helpful
12
Q
*Ethylene glycol: ANTIDOTES
A
- Ethanol: competition for alcohol dehydrogenase
o Disadvantage: CNS depression, metabolic acidosis - 4-methylpyrazole (fomepizole): inhibition of alcohol dehydrogenase
- *caveats
o Timing is key: need to give prior to complete bioactivation of EG
o Wont work if already have significant kidney damage
13
Q
Ethylene glycol: diagnosis
A
- Examine muzzle, paws, vomitus, urine with a Woods lamp
- EG semi-quantitative test (limit of detection corresponds to lethal dose in cats)
- Send out test
- Supportive clinical pathology tests: blood gas, chemistry, UA
- Abdominal ultrasound: medullary rim sign and hyperchoic (due to crystals)
- Histologic findings: CaOx crystals
14
Q
Ethylene glycol: prognosis
A
- Depends on amount consumed AND time elapsed since ingestion and treatment
- Good if treated by 5hrs post ingestion (dogs) or 3hrs (cats)
- Poor prognostic indicators
o Calcium oxalate crystals in urine
o Azotemia and oliguria
o Anuria
15
Q
Nicotine
A
- Ingestion of different products (cigarettes, nicotine gum or patches, chewing tobacco, etc)
16
Q
Nicotine: target and mechanism
A
- TARGET: CNS
- Activation of nicotinic acetylcholine receptors in autonomic ganglia
17
Q
Nicotine: clinical features
A
- Lower dose: CNS/neuromuscular excitation
- Higher dose: CNS excitation followed by CNS depression
- GI: vomiting, defecation, salivation
- CV: bradycardia or tachycardia, hypotension or hypertension, arrythmias
- Miosis
- CNS: agitation, hyperexcitability, tremors, convulsions
o High doses=depression (respiratory failure)
18
Q
Nicotine: management
A
- No specific antidote
- Decontamination: emesis induction, AC if NOT contraindicated
- Renal excretion: IVFT
- Frequent monitoring of CV system
- Respiratory depression: oxygen, intubation, manual ventilation
- Tremor/seizure control
- Nicotine gum may contain xylitol: manage xylitol toxicosis as well
19
Q
Nicotine: diagnosis
A
- History of exposure
- Send OUT test for nicotine in serum/plasma/urine
- *lots of DDx
20
Q
Nicotine: prognosis
A
- Poor with higher doses
o Prognosis improves if animals can stabilize within 4hrs
21
Q
Bleach
A
- Strength varies between products
- Exposure: chewing on containers, drinking product from buckets, swimming in recently treated pools
- MUCOSAL irritation: household
- Corrisivie injury: concentrated products
22
Q
Bleach: MUCOSAL IRRITATION
A
- Hypochlorite + acid=chlorine gas, hypochlorite + ammonia=chloramine
- Corrosive to GIT
- Inhalation: irritation and respiratory symptoms
- Ocular: corneal irritation, damage
23
Q
Bleach: dilute clinical features
A
- Hypersalivation
- Mild vomiting
- Anorexia
- Diarrhea
- Depression
24
Q
Bleach: concentrated products clinical features
A
- CORRISVE INJURY
- Can lead to SERIOUS SECONDARY PROBLEMS
o Perforation, septic peritonitis
o Stricture formation
o Non-cardiogenic pulmonary edema
25
Bleach: respiratory
- Coughing, sneezing, retching
- Severe: pulmonary edema, dyspnea
26
Bleach clin path
- Hypernatremia, hyperchloremia=hyperchloremic metabolic acidosis
27
Bleach: decontamination
- DO NOT INDUCE VOMITING
- AC=wont work b/c corrosive
- Dermal: gentle washing and E-collar
- Respiratory: fresh air
- Ocular: rinse with physiologic saline
28
Bleach management
- Decontamination (other card)
- Oral administration of milk or water (trying to dilute the bleach)
- Anti-emetic
- Evaluate severity of corrosive injury and monitor progression
- Gastroprotectants
29
Bleach: diagnosis
- History of possible exposure
- Smell of bleach on the patient or see bleached hair
30
Smoke inhalation
- Major cause of death from housefires
- Complex mixtures
- Thermal injury, chemical injury, systemic toxicity
- Toxic agents: extremely variable
31
What are the categories of toxic combustion products?
- IRRITANTS
- SIMPLE ASPHYXIANTS
- CHEMICAL ASPHYXIANTS
32
*Irritants: smoke inhalation
- Produce local effects on respiratory tract
- Hydrophilic=upper respiratory tract
- Lipophilic=deeper into lungs
- Ammonia, acrolein, PVC, sulfur dioxide, etc
- *mucous production=difficulty breathing
33
*Simple asphyxiants: smoke inhalation
- Displace oxygen
- CO2, methane, oxygen-deprived environments
34
*chemical asphyxiants: smoke inhalation
- Prevent O2 utilization
- CO, HCN, H2S, nitrogen oxides
35
Smoke inhalation: clinical features
- Severe respiratory problems
o Cough, stridor, bark change
o Injury of face, lips, eyes
o Dyspnea, tachypnea, tachycardia
o Cyanotic or cherry red MM
o Cause of death=asphyxiation
- CNS depression due to asphyxiation
- May have burns to other areas of body
36
Smoke inhalation: diagnostics
- Arterial blood gas
- carboxyHg
- MetHg
- Thoracic radiographs
- *consider bronchoscopy and laryngoscopy
37
Smoke inhalation: management
- Respiratory support: priorities are maintenance of ventilation and oxygenation
o Get 100% O2
o Bronchodilators
o Mechanical ventilation
o Coupage
o Tracheosomy may be required
- CV monitoring and treatment as needed
- Regular neurological monitoring
- Generatl supportive care: IVFT, pain control
