Prologue

Horses are impressive animals that have been domesticated and highly regarded by human civilizations for thousands of years. Horses have changed the lives of people in momentous ways throughout the advancement of human culture and continue to provide important functions for human societies as both working and pleasure animals. Veterinary medicine developed around the health of the horse because of people's dependence on the horse for various tasks from transportation, agriculture, and war time support to shipping, commerce, and sport.

Advances in the human and veterinary medical fields flourished during the last century and continue to develop at a rapid pace. Emergency and critical care medicine and surgery only recently blossomed in veterinary medicine over the last three decades and advances continue in both large and small animals (Mathews 2017). Emergency triage in human medicine is an older field - dating to the 1960s, and its scope and importance continue to evolve (Suter 2012).

Veterinarians often look to human physicians for guidance on emerging ideas and techniques since they often lead the medical field. Similarly, we can look to our human colleagues for advice on emergency triage and learn from their mistakes and experiences.

More than three decades have passed since the publication of "The Ten Commandments of Emergency Medicine" where Wrenn and Slovis provided emergency doctors with guidance on triage of the critically ill human patient (Wrenn and Slovis 1991). Recently, Evans and Slovis updated this editorial, providing a resident's perspective (Evans and Slovis 2020).

The editors are excited to present the first "Ten commandments of Equine Emergency Medicine" as applied to the horse, and based upon the recommendations from Wrenn, Evans, and Slovis.

Ten commandments of Equine Emergency Medicine:

1. Secure the ABCs quickly, carefully, and safely
2. Remember fluids, electrolytes, oxygen, and glucose
3. Always perform a thorough physical exam
4. Assume the worst and prioritize triage over diagnosis
5. Stabilize patients first and triage effectively
6. Look for the common red flags
7. Trust no one, believe nothing (not even yourself)
8. Learn from your mistakes
9. Do unto others as you would your family (including clients, colleagues, trainers, and referring veterinarians)
10. When in doubt, always err on the side of the patient

1. Secure the ABCs Quickly, Carefully, and Safely

The most important aspect of emergency triage is stabilization of the patient's airway, breathing and circulation (Wrenn and Slovis 1991; Evans and Slovis 2020). Specifically, the veterinarian should act to ensure the airway is patent, the patient's ventilation is adequate, and the cardiovascular function is sufficient (Chapter 1 - How to triage emergency conditions in the horse). Securing these vital parameters first will allow continued safe evaluation and management of the horse whether medical or surgical treatment is indicated. In human medicine, an ABCDE approach to emergency triage assessment has been described and is considered standard of care (Thim et al. 2012). The letters D and E represent the level of Disability or consciousness and Exposure of the body to look for any problems, respectively. Wrenn and Slovis expanded ABCDE to ABCDEFG, adding F and G; the letter F stands for Fetal viability, an essential part of evaluation for the pregnant female patient. The letter G in humans represents injury from falling off the stretcher and a reminder to always ensure the guard rails are in place. In the horse, the authors propose G stands for danGer. Horses are potentially dangerous animals, and when injured or sick they become more unpredictable and the risk of human injury increases. Veterinarians must prioritize human safety for themselves and all others working near the animal.

ABCDEFG emergency triage of horses:

• A - secure animal's Airway
• B - maintain adequate Breathing
• C - ensure sufficient Cardiovascular function
• D - evaluate level of consciousness or Disability
• E - perform thorough physical Exam
• F - assess Fetal viability in pregnant mare
• G - prioritize human safety as horses are danGerous

2. Remember Fluids, Electrolytes, Oxygen, and Glucose

Emergency fluid resuscitation is the foundation of veterinary emergency critical care, and targeted fluid therapy is invaluable in both primary and referral clinical practice. Fluid therapy with crystalloids and colloids will help stabilize the cardiovascular system and restore tissue and organ oxygenation in states of hypovolemia and shock. Electrolytes are an important step in emergency assessment as many conditions result from or are exasperated by electrolyte abnormalities. Oxygen therapy via face mask, intranasal or intratracheal routes in the critical equine patient is a simple, effective step for stabilizing animals suffering cardiorespiratory problems or other critical illness. The provision of nutritional support via glucose or other treatments should be considered with all emergency cases in horses, especially those that are malnourished, chronically ill, or have not eaten for several days.

3. Always Perform a Thorough Physical Exam

Emergency problems in horses may result from disease, injury, or abnormalities with many body systems. A concise, preliminary evaluation will guide emergency triage, and, in many situations, veterinarians must work quickly to stabilize the animal. Following patient stabilization, a more focused clinical exam is indicated to assess the affected body system(s). This exam should be focused yet thorough to avoid missing associated problems, complications, or sequalae. For example, a horse suffering thoracic trauma may initially need the following for emergency stabilization: close or bandage open chest wounds, control hemorrhage if required, remove pleural air, provide intranasal oxygen therapy, administer intravenous fluids, antibiotic, and anti-inflammatory medications. Once stable, a focused examination of the thoracic and abdominal cavities is indicated to determine the extent of injury. This may include palpation of the chest wall for asymmetry or signs of chest wall instability and rib fracture, thoracic and abdominal auscultation and ultrasound, rectal palpation, thoracic and/or abdominal fluid collection, and evaluation of the patient for other extra-thoracic injury.

4. Assume the Worst and Prioritize Triage Over Diagnosis

Remember it is the primary goal of the emergency clinician to identify or rule out problems that are life-threatening (Evans and Slovis 2020). We must consider the most serious problems that could be associated with a given clinical sign, even if they are unlikely (Wrenn and Slovis 1991). To do this effectively, veterinarians should work to identify problems that require emergency attention and not focus on obtaining a diagnosis. For example, it is not paramount to know that a horse with colic has colitis versus a large colon volvulus, but rather to make the correct decision for medical or surgical management. Once that decision is made, securing the diagnosis parallels triage, and if the patient's condition deteriorates despite management, re-evaluation of that initial decision is appropriate. Making the correct triage decisions is the foundation of emergency medicine whether human or horse.

5. Stabilize Patients First and Triage Effectively

Emergency stabilization of humans, horses, and other animals is the primary responsibility of the emergency clinician; and effective triage skills are essential. Navigating the triage of a critical horse patient requires knowledge, experience, and leadership. Knowledge: the clinician must consider the various clinical problems and diseases that may cause various clinical signs; experience: nothing replaces experience for stabilizing a sick or injured horse; leadership: effective clinicians will be able to manage the situation to secure the safety of themselves and others, and to provide quick decisions for management. Most horses with emergency conditions present with some degree of hypovolemia, and fluid therapy is one foundation of patient stabilization. Other life-saving triage decisions may include blood transfusion for acute hemorrhage, limb stabilization for long bone fractures, tracheostomy for respiratory distress, and fetal manipulation for dystocia.

6. Look for the Common Red Flags

Because emergency triage happens quickly with limited medical history and patient information, understanding important signs and problems to look for in patients will help guide effective triage (Wrenn and Slovis 1991). First and foremost, evaluation of a horse's vital signs is indicated: Heart Rate, Respiratory Rate, Body Temperature, and Blood Pressure. Effective triage depends upon early recognition of disease, and these vital parameters help detect problems and guide decision making. For example, a horse with a high respiratory rate or labored breathing will receive respiratory support (e.g., intranasal oxygen or tracheostomy) and a focused respiratory exam. Second, an animal's age -...