Owners can provide significant medical assistance at the scene of the injury. At the time of the initial telephone call, the owner should be questioned about the level of consciousness, breathing pattern, type of injury or toxicity, and even some aspects of the animal's perfusion (eg, gum color, level of responsiveness, heart rate). The first concern is for the safety of the owner. Placing a light cloth over the head of the animal can lessen external stimuli that may cause fearful and aggressive reactions. Owners can be instructed as to how to muzzle most dogs using a long strip of fabric if there are no facial injuries or respiratory distress. Cats can be placed in dark boxes to minimize stress during transport; the box should have holes large enough so that the cat can be observed. It is vital that the owner adequately restrain the pet before starting any first aid procedures to ensure the safety of the owner and pet. When moving the animal, motion of the head, neck, and spine should be minimized. A flat, firm board of wood, cardboard, or thick fabric can be used to provide support. Radiographs can also be taken through these materials without having to move the animal when it arrives at the hospital. Rapid detection of cardiopulmonary arrest (CPA) in an unconscious animal can be difficult for owners. The pet’s lack of response to external stimuli or presence of limp body tone are unreliable indicators of CPA. Instructing owners to feel for a pulse or heart rate can delay intervention. Instead, owners can be instructed to watch for chest excursions and to touch the cornea or eyelids to elicit a corneal or palpebral reflex in an unconscious pet, with absence of one or both indicative of CPA. Mouth-to-nose resuscitation and chest compressions (see Cardiopulmonary Resuscitation) may provide enough respiratory and circulatory support to maintain life during transport. If the animal is cyanotic and collapsed (and was pawing at the face), an upper airway obstruction may be present; the owner should be instructed how to perform a Heimlich maneuver or sudden chest compression to relieve the obstruction and then to manually clear the airway. If the animal is unconscious and not breathing, the owner should be instructed to close the animal’s mouth, place their lips over the animal’s nostrils, and initially give 3–4 strong breaths. If the animal’s breathing does not become spontaneous, the owner should breathe for the animal at a rate of 10 breaths/min. The owners can also be instructed to compress the esophagus behind the mandible on the left side so that most of the air will go down the airway instead of into the stomach. Chest compressions should be initiated at a rate of 100–120/min. A compression:ventilation ratio of 30:2 can be performed. This necessitates another person to drive during transport. Owners should be asked whether hemorrhage is ongoing or whether bleeding was seen at the site of injury. Pulsating arterial bleeding should be controlled by direct digital pressure and then by a pressure bandage. Any long pieces of fabric or gauze can be used. Often, washcloths and hand towels are adequate when applied with mild pressure. Additional material can be placed over the original bandage if it becomes soaked with blood. If the bleeding from a limb is venous (dark, oozing), the limb can be elevated above the heart. Tourniquets should be used only on appendages (eg, limbs, tail) when compression wraps have failed to control bleeding. The tension on the tourniquet must be relaxed to allow blood flow to the distal limb and then retightened every 5–8 min. Penetrating foreign objects (eg, sticks, arrows) should be left in place during transport; however, care should be taken to guard against movement of the object to prevent further injury. It is often necessary to stabilize the shaft of the penetrating object just outside the body and, holding it firmly, cut off the shaft, leaving a portion exposed so it can be easily located. In dogs with fractures below the elbow or stifle with significant displacement—and, therefore, concern for movement causing damage to muscle, nerve, vessels, or bone—support can be provided during transport. Once the pet has been adequately restrained, the owner can make a support splint from a rolled newspaper or magazine, which is secured in place by long pieces of fabric or duct tape. Animals with altered mentation after trauma should be transported with the head level with the body or elevated 20°. There should not be any jerking or thrashing motions, and manipulations of the neck or occlusion of the jugular veins should be minimized. If a toxic ingestion is present, the owner should be instructed to bring the animal immediately to a veterinarian. Instructing an owner by phone to administer hydrogen peroxide or other substances carries the risk of further injury such as a vagal response (resulting in collapse and bradycardia), choking on vomitus, aspiration pneumonia, further toxic injury from caustic substances, or mucosal injury from hydrogen peroxide administration. If possible, the container of the likely toxin should be brought in.