Carbon Monoxide Toxicosis in Dogs
Carbon monoxide, an odorless and colorless gas, poses a significant threat to both dogs and humans alike. It stems from the incomplete combustion of carbon fuels and can prove toxic upon inhalation. Dogs may encounter carbon monoxide from various sources such as unventilated kerosene or propane heaters, vehicle exhausts, gasoline engines, or fumes from carbon-based heating systems.
Upon inhalation, carbon monoxide swiftly enters the bloodstream where it binds with hemoglobin, forming carboxyhemoglobin. This process diminishes the delivery of oxygen throughout the body, resulting in decreased oxygen utilization within the brain and heart. Dogs typically face carbon monoxide toxicity due to human errors, such as being confined in areas where carbon monoxide is present. For instance, leaving a dog in a closed garage with a running car can expose them to dangerous levels of carbon monoxide in as little as ten minutes. Similarly, animals trapped in burning buildings are at risk of carbon monoxide poisoning. Prolonged exposure to carbon monoxide results in hypoxemia and, ultimately death.
Symptoms and Types
Symptoms of carbon monoxide poisoning can vary depending on the concentration and duration of exposure. They may manifest as acute or chronic conditions.
Acute symptoms include:
- Sleepiness
- Cherry red skin and mucous membranes (e.g., nostrils, lips, ears, genitals), though this may not be readily visible in most animals
- Weakness
- Lethargy
- Difficulty breathing
- Seizures
- Abortion in pregnant animals, particularly in late gestation
- Depression
- Deafness
- Uncoordinated movements
- Coma
- Death
Chronic exposure to carbon monoxide may result in:
- Nausea
- Elevated levels of acids in the blood (acidosis)
- Vomiting
- Coughing
- Flu-like symptoms
- Decreased exercise stamina
- Gait disturbances
Causes
Causes of carbon monoxide exposure include:
- Incomplete combustion of carbon fuels
- Accidental confinement of a dog in a garage with a running automobile engine
- Insufficient ventilation in areas containing carbon monoxide sources (e.g., fireplace, oven, barbecue grill)
- Poorly ventilated furnaces
- Gas water heaters
- Gas or kerosene heaters
- House fires
Diagnosis
Diagnosing carbon monoxide toxicity in your dog begins with immediately removing them from the carbon monoxide source, as it poses a life-threatening situation requiring prompt veterinary attention. Upon arrival at the veterinary clinic, your veterinarian will initiate oxygen therapy to eliminate carbon monoxide from the blood and restore your dog’s oxygen levels to normalcy.
During oxygen therapy, your veterinarian will conduct various diagnostic tests, including collecting blood samples for analysis. These tests encompass a complete blood count, biochemistry profile, urinalysis, and other relevant fluid tests. Additionally, samples will be collected to measure carboxyhemoglobin levels in the blood, which is crucial for determining the severity of carbon monoxide exposure and tailoring the initial treatment plan.
In acute cases, carboxyhemoglobin levels typically increase and decline within a few hours once the source of carbon monoxide exposure has been eliminated. Blood tests will also assess acid levels, as they tend to elevate in response to carbon monoxide poisoning and guide the diagnostic process and subsequent medical intervention. Your veterinarian may also employ an electrocardiogram (ECG) to evaluate potential cardiac involvement.
Treatment
If you suspect that your dog has been exposed to high levels of carbon monoxide, immediately contact your veterinarian for assistance. Meanwhile, move your dog away from the source of the toxic gas to an area with fresh air. Upon arrival at the veterinary clinic, emergency treatment will commence to restore sufficient levels of oxygen to the vital organs.
The primary method for initiating rapid recovery is the administration of 100 percent pure oxygen supplementation. Additionally, fluids will be administered to enhance blood perfusion to vital organs such as the brain and to normalize elevated acid levels in the blood.
Living and Management
During your dog’s recovery from carbon monoxide poisoning, it’s important to limit its activity for at least six weeks. Instead of engaging in long walks, opt for shorter ones, and reduce playtime and exercise until your dog has fully regained its physical capabilities. Providing extra affection and creating a calm and relaxed environment for your dog can be beneficial during this period.
Monitor your dog closely for any recurrence of symptoms and seek veterinary assistance if you observe any concerning signs. Some animals may exhibit nervous system abnormalities weeks after initial recovery, so remain vigilant and consult your veterinarian if needed.
As carbon monoxide poses a threat to both humans and dogs, it’s essential to install carbon monoxide detectors at home to prevent potential or recurring incidents. The primary line of prevention lies in human awareness and proactive measures to safeguard dogs from exposure to carbon monoxide sources.