TOP 3 Summer Emergencies
By: Danna Torre, DVM, DACVECC
Board-Certified Critical Care Specialist
Now that summer is squarely upon us, we at VSEC start to think about and plan for emergencies that are more common in the warmer months. Taking an active role in educating clients as well as support staff is an important step we all can take to help prevent an issue or to act quickly in an emergency situation.
Here are three of the most common emergencies seen during the spring and summer months in the VSEC emergency room.
The springtime and summer definitely seems to bring more lilies exposures into the hospital. Plants in the Lilium and Hemerocallis genera (such as Easter lilies, tiger lilies, Japanese snow lilies, rubrum lilies, and day lilies) are toxic to pets. Cats are very sensitive to lily toxicity with dogs being less sensitive. You typically only see mild gastrointestinal signs in dogs. While in cats it causes severe systemic changes in the form of nephrotoxicity.
- The leaves and flowers are both nephrotoxic and as little as 2 to 3 leaves are reported to be lethal.
Typical clinical signs of ingestion include vomiting, depression, anorexia, and polyuria with dehydration. Cats usually vomit within 2 to 4 hours. By 12 to 24 hours, polyuria and then dehydration develops. This dehydration ultimately causes necrosis to the renal tubules and subsequent anuria develops. If this toxicity is left untreated cats usually die within 4 to 7 days.
- Therefore treatment for exposure to lilies should be immediate.
If a cat presents within 2 hours of ingestion, decontamination should be attempted. Getting cats to vomit can be challenging. I typically use dexdomitor (dexmedetomidine ) at a dose of 10mcg/kg intramuscularly. This can cause sedation in addition to vomiting so once the cat has vomited we recommend reversing immediately with an equal volume (of the dexmedetomidine dose) of atipamezole (antisedan). We would then recommend giving an anti-nausea medication and administering 5 to 10ml per pound of activated charcoal with sorbitol.
Cats with lily exposure should have a baseline specific gravity as well as renal enzymes check. Ideally we recommend hospitalization for at least 72 hours for fluid diuresis. These patients are also usually treated with anti-nausea medications and gastro-protectants. We typically recheck renal enzymes and electrolytes at least once a day. If cats become azotemic, unfortunately the only known effective treatment option is hemodialysis. Fluid diuresis at this time is ineffective at treating these cats. Hemodialysis has variable success rates.
Heat stroke is a serious and life threatening syndrome seen mostly in dogs in the late spring to early summer months. Heat stroke occurs when an individual is not given ample time to adjust to warm temperatures. The body has developed a relatively effective thermoregulatory system to protect itself from overheating. These systems develop over several weeks to a month. This process is called acclimatization. When a patient does not have enough time to develop these protective measures, heat stroke can occur.
Thermal homeostasis is maintained by a balance between heat load (environmental heat and heat generated through metabolism and exercise) and heat dissipating mechanisms controlled by temperature-sensitive centers in the hypothalamus. Body temperature increases when heat load exceeds heat dissipation. Heat dissipation occurs in four mechanisms: convection, conduction, radiation and evaporation. Dogs mainly dissipate heat by evaporation. They do this by panting. Heat loss in dogs also occurs via radiation and convection via the skin. This is facilitated by increased cutaneous circulation as a result of increased cardiac output and sympathetic-mediated peripheral vasodilation. Shunting of blood to the periphery is a trade-off with blood supply to the viscera (ie intestines and kidneys). Conduction is the transfer of heat from one substance to another. This form of heat dissipation is used least frequently in dogs. A warm, humid environment and exercise are the two most common heat loads that dogs experience and may cause extreme hyperthermia, even in animals that have functional heat dissipating mechanisms. Evaporative heat loss may be diminished by humid climatic conditions, closed confinement with poor ventilation, and upper respiratory abnormalities (such as conformation, laryngeal paralysis or collapsing trachea). Diminished radiation and convective heat loss from the skin may occur as a result of hypovolemia from any cause, such as poor cardiac output, obesity, extremely thick hair coat, or lack of acclimatization to heat. Such situations that combine high heat load and diminished heat dissipation may result in a rapid and extreme body temperature increase.
The severity of clinical signs varies from patient to patient. Some patients have only mild gastrointestinal signs while others are in fulminant multiple organ dysfunctions. These patients can have low, normal, or high temperatures. They typically are in a state of hypovolemic shock with weak pulses, hyperemic mucous membranes, and a short capillary refill time. Rarely ventricular arrhythmias can be present. The most severely affected patients can have protracted vomiting and diarrhea. In some instances, the vomiting can lead to aspiration pneumonia so evaluation of the respiratory system is essential. In addition, a risk factor for heat stroke is the initial presence of laryngeal paralysis so patients should be evaluated for the character of their breathing. In the most extreme cases of heat stroke patients can progress into a state of DIC (disseminated intravascular coagulopathy), anuric/oliguric renal failure, and neurologic dysfunction. Unfortunately when these changes occur heat stroke can be fatal.
The first line of defense for heat stroke is education of the client. It is important to speak to clients with older, obese, systemically ill or brachycephalic dogs about the pitfalls of excessive physical exertion with the new onset of the warmer months.
- It is important to educate clients about acclimatization and the importance of easing their pets into outdoor activities during the spring and early summer.
Dogs during this time should have plenty of access to fresh water. It is also essential to teach owners the warnings signs of heat stroke. Excessive panting, extreme lethargy, and an altered mentation can be warning signs of heat stroke. If these changes are evident owners should attempt to take their dogs temperatures at home. With a temperature above 104 F active cooling should be instituted. Owners should “hose” their pets with cool water until a temperature of 103 F to prevent over cooling. Owners should then be instructed to immediately transport their pet to an emergency facility. The key treatment at any emergency facility will be aggressive fluid support. Depending upon the severity of the patient’s condition, oxygen, antibiotic therapy, plasma therapy and renal support measures may be incorporated into the treatment regimen. Unfortunately heat stroke can be fatal. Prevention of this condition involves education to prevent excessive exposure to heat for those patients that are most sensitive.
Hit By a Car
Hit by a car is a tragically common emergency that we see at VSEC. The most common complications that we see following these types of accidents can be anything from superficial abrasions to significant orthopedic injuries to severe head trauma to massive abdominal and thoracic trauma to even acute death.
- The important systems to evaluate after vehicular trauma are heart, brain and lungs.
Mentation can be evaluated with the use of the Glascow coma scale and can be used to follow either improvement or deterioration. When evaluating the cardiovascular system heart rate, capillary refill, mucous membrane color and pulse quality are useful tools. Heart rate should be normal, capillary refill time should be 2 seconds or less, mucous membrane color should be pink and pulses should be strong and of good quality. If any of these parameters are altered or out of the normal limits we worry about adequate at the tissue level. Respiratory rate and effort are good indicators of pulmonary function but can also be altered from hypovolemia, pain and head trauma.
After the assessing and the triaging the patient, an intravenous catheter should be placed and a minimal database of packed cell volume, total solids, blood glucose and azostick should be performed. Obviously full bloodwork, urinalysis, chest and abdominal radiographs should be considered. If available an ultrasound is a valuable tool to evaluate for free gas or free fluid through the use of the T-FAST and A-FAST techniques. Monitoring heart rate, respiratory rate, pulse oximetry, and blood pressure is important every 4 to 6 hours depending upon the severity of the injuries.
Fluid support is an essential stabilization measure in the hit by a car patient. Fluid support in these patients is a dynamic, changing process that constantly needs to be re-assessed. A fluid bolus is usually the first step in treatment of the tachycardiac, hypotensive patient. This fluid challenge should be followed with re-assessment in order to determine future fluid support requirements. Pain control through the use of appropriate analgesics such as hydromorphine, methadone, fentanyl or the use of continuous infusion of ketamine/lidocaine and an opioid derivative depends upon the patients’ severity of injuries. Steroid therapy has fallen out of favor and is not recommended.
- Steroid therapy can actually be harmful in these patients.
A thorough orthopedic evaluation should be performed once the patient is stable. Wounds should be sterilely dressed and fractures/luxation should be stabilized in accordance with proper bandaging techniques. Client education is essentially to preventing this type of injury. Dogs should be on a leash with a properly fitting collar or harness when taking walks outside. And both dogs and cats should be microchipped to allow quick determination of ownership when necessary.
Dr. Danna Torre is a Board-Certified Emergency & Critical Care Specialist at the Veterinary Specialty & Emergency Center. The Veterinary Specialty & Emergency Center operates state-of-the-art emergency and specialty veterinary hospitals that are open 24/7/365 in both Levittown PA and Philadelphia PA. For more information about our world-class emergency and specialty care, please visit VSEC on the web at www.VSECVET.com.