Canine Pneumonia

By Beth Guerra, DVM  

Pneumonia is an infection in the lower airways that causes inflammation in the lungs. Organisms can be bacterial, viral or fungal in nature. The infection is established when these organisms are inhaled, aspirated (from gastrointestinal contents), or spread through the blood from other body systems. The usual defense system of the body traps infectious organisms in the mucus lining the respiratory tract and moves them upward where they can be expelled by coughing. Failure of this mechanism allows bacteria or fungi to colonize the airways. Once the infection is established, secondary inflammation can develop, impairing normal oxygen exchange.

Bacterial pneumonia is frequently seen at our facility. The two most dominant types of organisms are Bordatella bronchiseptica and E. coli. In young or incompletely vaccinated dogs, we often see Bordatella pneumonia, otherwise known as kennel cough pneumonia, which is a contagious disease. The E. coli organism is the most common inhabitant of the upper GI tract and infection results from aspiration of stomach contents.

Aspiration pneumonia is by far the most common type of pneumonia we encounter in our ICU. Patients at risk for aspiration include sedate or recumbent animals, or those recovering from anesthesia. Pets that have vomiting, regurgitation or reflux, or altered esophageal motility are also at high risk for aspiration. Another condition, known as laryngeal paralysis, can also precipitate an aspiration event.

Often the only symptom in these dogs is acute lethargy and inappetance. There may be weight loss, fever, or a moist or productive cough. Diagnosis is made by thoracic x-rays, but bloodwork often reveals an elevated white blood cell count, and can also help to rule out other predisposing conditions. To further support a diagnosis, samples of the lower airway bacteria are collected by endotracheal or transtracheal wash, where sterile saline is introduced in small amounts into the lower airway in an attempt to retrieve bacterial organisms for culture. This will help direct antibiotic therapy.

Dogs with pneumonia can range from fairly stable patients that are eating and active to patients that are severely ill and dependent on oxygen. In the former, treatment with oral antibiotics for an extended period may be all that is required. In the latter, hospitalization is recommended to provide more aggressive supportive care. Systemic hydration is important to help loosen secretions and also because the patient is usually not eating or drinking. Intravenous antibiotics are usually given for a minimum of 48 hours. Oxygen therapy, via nasal cannula or chamber, is needed in those patients with low oxygen saturation. Nebulization with saline, followed by coupage, or gentle percussion to the chest cavity, can help the patient cough up secretions.

Several years ago, we examined the records of the animals we had treated for pneumonia over a two-year period. We treated 94 cases and were able to send home 82%. In animals who were less than two years old, 95% went home. Most of the cases that we could not save were found to have an underlying condition such as a megaesophagus, laryngeal paralysis, other neurologic disease, or concurrent diabetes. 

The treatment for pneumonia often includes four to six weeks of antibiotic therapy. Follow-up chest x-rays are very helpful in tracking the progression of the disease. Once a patient is eating and stable without oxygen, convalescence can continue at home with rechecks as needed. 

Salmon Poisoning Disease

By Beth Guerra, DVM

Salmon poisoning disease (SPD) has been identified in the Pacific NW down through northern California. Because of the name, most people think of it as some sort of food poisoning obtained by eating bad salmon. The organism responsible for SPD is actually a small microscopic (rickettsial) organism located within the immature form of a fluke that colonizes the flesh of salmon. If raw fish are ingested by dogs, the fluke will mature within the intestine and release the rickettsial organism that causes disease.

Symptoms usually occur within five to seven days of ingestion of infected fish and may include fever up to 104F, vomiting, diarrhea, loss of appetite and weakness. The body’s lymph nodes are usually enlarged and can be palpated on exam. Diagnosis is often made by identifying the fluke eggs on a fecal exam, but a CBC/chemistry, abdominal x-rays or ultrasound should be performed to rule out any concurrent diseases.

Patients are generally hospitalized for aggressive supportive care due to rapid onset of symptoms. Diarrhea and vomiting can be severe or become bloody, so fluid support is required. Medications include a tetracycline antibiotic to eradicate the rickettsial organism as well as a general deworming medication to treat for the flukes. If SPD is caught early and treated appropriately, the prognosis is good and patients usually recovery fully. 

Are these foods REALLY toxic?

By Beth Davidow, DVM DACVECC

There are a number of foods that are now known to be toxic to pets. I tend to wonder each time I hear of a new toxicity, “is that really true?” I often think, “Well, I’ve seen lots of dogs who eat that who haven’t had a problem.” The growing list of toxic foods for pets now includes chocolate, onions, grapes, raisins, and chewing gum containing xylitol (many of the sugar free gums). Although I read these new reports critically, working in emergency, I have now seen all these toxicities first-hand.

Chocolate toxicity has been known to many of us for years. Theobromide, a methylxanthine, is the main toxic component, and causes extremely fast heart rates, tremors, and can lead to seizures. The darker the chocolate, the more theobromide is contained in each ounce and the less the pet has to eat of it to cause problems. White chocolate is actually not toxic at any amount. A 60-pound lab would need to eat 20 ounces of milk chocolate to have moderate to severe signs but only three ounces of dark bakers chocolate. Depending on when the chocolate was ingested, we might recommend inducing vomiting or having us administer activated charcoal. (Activated charcoal binds toxins that are in the stomach or intestinal tract so they can’t be absorbed into the blood stream.) We’ve seen many dogs that presented with agitation and severely elevated heart rates. Most have done well but some needed 24-48 hours in the hospital on IV fluids and medication to decrease the dangerously high heart rates.

Onion toxicity is one I hadn’t seen until a few years ago. Onions and other members of the Allium family (shallots, garlic, and green onions) contain a compound that can weaken red blood cells. The red blood cells break down causing anemia (lack of red blood cells) and hemoglobin (the protein inside red blood cells) to spill into the urine. Dog’s red blood cells have less antioxidants than people’s making their cells more prone to damage. Cats are even more susceptible to red blood cell damage. Ingestion of 5g/kg of onion in cats or 15-30 g/kg in dogs can lead to clinically important hemolysis. Damage consistently happens in dogs who ingest more than 0.5% of their body weight in onions at one time. A few years ago, an English setter was referred to us for inappropriate urination and red colored urine. It turns out he had eaten three cups of onions the day before – 1.5% of his body weight! The red color was hemoglobin in his urine. He became very anemic four days after he ate the onions and needed a transfusion. To complicate matters in his case, he also had a bacterial urinary infection. The combination of the hemoglobin going through his kidneys and the infection, despite antibiotics and IV fluids, led to acute kidney shut down. After 10 days of hospitalization, antibiotics, and IV fluids, he is doing well at home.

Grape and raisin toxicity was first reported by the National Animal Poison Center in 2001. At that time, they knew of 10 reported cases of acute kidney failure with ingestion of quantities varying from 0.2 oz/lb to 4.4 oz/lb. A retrospective study was published in 2005 in the Journal of Veterinary Internal Medicine involving 43 cases. Of the 43 cases, 20 died or were euthanized due to a poor prognosis. Unfortunately, it is still not known why some dogs, but not all dogs, develop acute kidney failure from ingestion of these foods. Pesticides, fungus and heavy metal contamination have been ruled out as causes and it appears that the toxic principle is in the flesh and not in the seed. Last year, we treated a dog who developed acute kidney shutdown after eating grapes off a vine at a friend’s house. The dog survived and is now doing well but was hospitalized for almost two weeks and required subcutaneous fluids for many weeks afterward. We do recommend inducing vomiting, activated charcoal and IV fluid diuresis with any grape ingestion over 0.7 oz/kg or raisin ingestions over 0.1oz/kg. Induction of vomiting is recommended up to eight hours after ingestion in these cases as in many of the cases reported to National Animal Poison Center, raisins were still found in the vomit at this point.

Xylitol is a sugar substitute that is good for people on a low carbohydrate diet, those with diabetes or those watching calories. It is found in sugar free gum, some toothpastes (it can prevent oral bacteria from producing acids that damage tooth surfaces), and can be bought as a powder for cooking. Although the lethal dose is >130 g/day in people and greater than 20g/kg in mice, the metabolism is different in dogs. It appears that doses greater than 0.1g/kg can lead to hypoglycemia 30 minutes to 12 hours after ingestion. This is because in dogs, but not in people, xylitol causes a dose-related rapid, severe insulin release. In addition, acute liver failure and bleeding problems has been reported in eight dogs after eating xylitol containing products. Most of the dogs presented with vomiting and lethargy nine to 72 hours after xylitol exposure. The reason for the liver failure is currently unknown. National Animal Poison Center does recommend vomiting induction, IV fluids, and careful monitoring of blood glucose and liver enzymes.

The NAPCC is a fantastic resource and we recommend that their phone number be easily accessible in your household. The Washington Poison Center now also has a veterinary toxicologist on staff and is also very helpful especially in cases of household chemicals or product exposure. In addition, our emergency doctors are very knowledgeable about toxicities and are always happy to answer questions at any time of day or night. (NAPCC, 888-426-4435 and Washington Poison Center, 800-222-1222)

Gastrointestinal Foreign Bodies

By Beth Guerra, DVM  

In my eleven years as a veterinarian, I have amassed quite a list of objects I have removed from the GI tract of dogs and cats. We veterinarians all have that one item we have pulled from the stomach or intestine that seems unique. I am constantly amazed at the ability of our furry friends to actually swallow these objects. I have seen some spectacular objects pass through with no problem, like straight pins and acorns, but I more frequently deal with patients where the offending object has caused an obstruction. Objects that make it into the stomach have two options; either they will be vomited up or try to leave the stomach through the pylorus. If the object is too big to advance into the intestine, it will remain in the body of the stomach and usually causes intermittent vomiting. Objects that advance into the small bowel will either pass without incident or cause a bowel obstruction.

Patients with GI foreign bodies can have a variety of symptoms, including vomiting, inappetance, or abdominal pain. Some pets will still want to eat but will vomit partially digested stomach contents shortly afterwards. In smaller dogs or cats, the foreign object can often be felt on abdominal palpation. Diagnosis is usually based on x-rays. Some objects, such as rocks or metal, show up easily on an x-ray, but others like cloth can be difficult to visualize, so a diagnosis of obstruction is made based on the appearance of the intestines and gas patterns. Abdominal ultrasound is used in those cases where the x-ray is inconclusive.

A rapid diagnosis and treatment of GI obstructions is ideal, especially when objects are obstructing the small bowel. The longer an object remains in the bowel, the greater the concern for complications such devitalized bowel or intestinal perforation. There can be pressure necrosis, or death of the tissue, over the object. This pressure necrosis can cause the tissue to tear and lead to leakage of intestinal contents into the abdominal cavity. In severe cases, the compromised bowel may need to be resected. If perforation has occurred, the resulting infection in the abdomen, called peritonitis, can be fatal.

Obstructing foreign bodies often need surgery. In some cases where a small, smooth object is in the stomach, the veterinarian may induce vomiting to see if the object can be retrieved. Alternatively, endoscopy can be attempted to pull the object out through the esophagus. If the object is sharp, very large or no longer in the stomach, surgery is indicated. The patient is usually started on aggressive fluid therapy to combat dehydration from vomiting, and in rare cases, this can encourage an object to pass. If the duration of symptoms is more than several days, or if there is concern for bowel perforation, surgery should not be delayed. With prompt treatment, pets often recover uneventfully from these surgeries.

Ingestion of foreign bodies can be prevented by providing your pet with toys that are adequately sized for the breed of dog to prevent accidental swallowing. You should also consider supervising your dog when offering treats such as large rawhides or greenies to make sure the treat is chewed slowly and not gulped down in large chunks. If you suspect that your pet has ingested something inappropriate or is showing clinical symptoms, a veterinary exam is recommended sooner rather than later.

Why Can’t Vets Diagnose My Pet Over the Phone?

By Beth Guerra, DVM

Our clinic fields numerous calls a day concerning pet emergencies. Owners will describe clinical signs and a bit of history, and then ask what could be wrong with their pet. Frequently, we encounter owners that are frustrated that we can’t give advice over the phone, or tell them what medications to give or if they can wait to see their regular veterinarian. Diagnosing a pet’s illness over the phone is almost impossible, and, if our guess is wrong, could be life threatening.  We always want to err on the side of caution to keep your pet safe.

The staff at ACCES is highly trained in phone triage, from receptionists to veterinary assistants and technicians. They will obtain basic information, such as age, breed, and prior medical problems, as well as current symptoms of concern. Their job is to determine if and when a pet needs to be evaluated by a veterinarian, but they are instructed to not try and diagnose over the phone. There are a variety of factors that go into making a diagnosis, and the most rudimentary, and often most important, are a basic history and physical exam by a veterinarian. In most cases, if there is any concern about a pet’s health, an exam is recommended.

In the veterinary profession, importance is placed on a valid veterinary-client-patient relationship. This means that the veterinarian has examined the pet and taken a thorough history. It is illegal to prescribe medications without establishing this type of relationship, which is why medications cannot be dispensed or recommended over the phone without seeing the pet. Even medications that are considered ‘common,' such as Benadryl, are known as off-label medications for pets and should not be given without direction from a veterinarian.

The most frequent request we get from owners is advice on how to treat their pet at home. In some cases, the owner may be financially restricted, or not able to bring their pet in for an exam due to a busy schedule. While it may seem like there should be a simple remedy for something like diarrhea, there can be myriad causes. Since pets can’t describe how they are feeling and often mask their illnesses, the owner may only have part of the picture. A history and exam can also help guide diagnostics to rule out certain diseases.

For example, we had a client call whose dog had been acutely vomiting. Based on the information obtained over the phone, the technician advised that the pet be seen on emergency. The owner was reluctant to come in and wanted to know how to treat the dog at home. Since vomiting can be caused by anything from dietary indiscretion to renal disease, it is difficult to determine an effective remedy over the phone. The owner was advised to withhold food and water for an hour and call if the dog continued vomiting. Several hours later, the owner did bring in the dog. A history and physical exam determined that the dog was exhibiting unproductive retching, not vomiting, and that the stomach had torsed in a condition known as bloat. The dog did well after fluid resuscitation and surgery, however, this condition can be fatal if undiagnosed and untreated.

The staff members at ACCES Seattle and Renton are available 24 hours a day to answer questions about your pet. One of our core values is client service, and we will do our best to provide you with helpful information. However, another of our core values is patient care, and that means receiving a diagnosis and proper medical care is of tantamount importance.