The following is adapted from Medicine for the Outdoors:

In all first-aid situations, the rescuer must remain calm. If you panic, you may lose control of the victim, as well as of yourself. To establish authority, speak and act calmly and purposefully. Allow the victim to discuss the incident, his (or her) situation, and his fears. If you can involve the victim in his rescue and treatment, it is often good for morale. Try not to be judgmental and save criticism for after the event. Avoid laying any blame on people; they may get hurt emotionally or become argumentative as a result. When communicating with a victim and bystanders, remember that you are not only caring for the victim, but in many ways, for family and friends. It is important to communicate frequently, honestly, and in a manner that is reassuring and inspires cooperation and hope.

1. Do not endanger additional inexperienced rescuers. If you cannot get to the victim easily, send for help. Approach all victims safely; don’t allow the sense of urgency to transform a sensible rescue into a series of risky, or even foolhardy, maneuvers. If it appears that the victim is too ill to be moved, set up camp and create a shelter immediately. In all cases, protect the victim from the elements from above and below.

2. If you have paper and a writing instrument, record your observations. If you send someone for help, have him carry a piece of paper that states the victim or victims’ location, the nature of the emergency, the number of people needing help, the condition of the victim(s), what is being done to treat the victim(s), and any specific environmental conditions or physical obstacles. Accident report forms are available from organizations such as The Mountaineers.

3. Always assume the worst. Assume that each victim you encounter has a broken neck or a heart attack until proven otherwise. Always be conservative in your treatments and recommendations for further evaluation or rescue.

4. Never move a seriously injured victim unless he is in danger from the environment or needs to be moved for medical reasons. Don’t encourage a victim to get up and “shake it off” until you have examined him as fully as possible for a potentially serious problem. If you must remain in a wilderness location for a prolonged period of time caring for a victim, remember to attend to the basic survival requirements, which include air (oxygen) for breathing, shelter, water, food, psychological support, and human waste disposal.

5. Don’t administer medicines or perform procedures if you are not sure what you are doing. The good Samaritan has certain legal protections for his actions so long as he operates within prudent limits and takes reasonable care. A good rule to follow is primum non nocere: “First of all, do no harm.” If you are not certain what to do and the situation isn’t worsening, don’t interfere. Explain to the victim that you are not a physician, but will do your best to get him through whatever crisis he has encountered, to the best of your knowledge and ability. If you encounter a victim who may be seriously ill, seek an expert opinion as soon as possible. Even if your treatment seems successful, it is wise to consult a physician if you would have ordinarily done so.

6. Listen carefully to the patient. The story of what happened and the medical history can be extremely important in making swift and appropriate medical decisions. Let the victim tell you what happened in his or her own words, and try not to interrupt unless it is important. If a victim has a sprained ankle, a comprehensive discussion may not be necessary, but if it is appropriate, try to elicit the following:

Current illness: What happened? When did it happen? Why did it happen? If the victim is suffering pain, describe its location, time of onset, whether it came on suddenly or gradually, whether it comes and goes, its quality (dull, sharp, cramping, etc.), how it is made worse or relieved, and whether the victim has suffered anything similar before (and if so, whether there was a medical diagnosis). Have the victim describe all symptoms, such as nausea, vomiting, diarrhea, blurred vision, shortness of breath, fatigue, cough, etc.

Prior illnesses and preexisting conditions: Have the victim describe any previous illness (heart attack, asthma, pneumonia, meningitis, etc.) and any current conditions (diabetes, anemia, abnormal heart rhythms, etc.) and how they have been and are currently being treated.

Surgeries: Have the victim list any surgical operations, such as appendectomy or knee surgery.

Allergies: This includes allergies to food, plants, insects, and medication(s) and the nature of the allergic reaction(s).

Immunizations, exposure to communicable diseases, foreign travel, recent dietary history: Any of these may be appropriate if the victim is perhaps suffering from an infectious disease, including food poisoning or toxic ingestion.

Review of systems: This is a comprehensive questioning of each organ system to determine if the victim has or has ever had symptoms referable to each system:

Head: headache, dizziness
Eyes: blurred vision, double vision, decreased vision, discharge, pain
Ears: decreased hearing, ringing in the ears, discharge from the ears, pain
Nose: nosebleeds, difficulty breathing, nasal discharge, sinus infection
Throat: sore throat, foreign body sensation, tonsillitis, hoarseness or difficulty talking, painful swallowing, difficulty swallowing
Dental: tooth loss, abscess, dentures
Neck: pain, decreased range of motion, arthritis
General: fever, chills, weakness, unintentional weight loss or gain, dizziness, history of intravenous drug use
Chest(lungs): difficulty breathing, shortness of breath, wheezing, cough (productive of sputum or nonproductive), coughing blood, history of tobacco use
Heart: palpitations, chest pressure-like sensation, chest pain
Abdomen: pain, mass
Gastrointestinal: nausea, vomiting (describe what is vomited), diarrhea (describe consistency), red blood in stools or dark black stools, yellow skin (jaundice), perianal itching, constipation, excessive gas, bloating, belching
Hematologic/immune: anemia, frequent infections, exposure to HIV
Genitourinary: change in frequency of voiding, painful urination, discolored or malodorous urine, back pain, blood in urine, history of sexual contacts, penile or vaginal discharge, date and character of last menstrual period (normal, abnormal), vaginal bleeding
Neurologic: seizure, weakness in any body part, numbness or tingling of any body part, difficulty with coordination or walking, difficulty with speech or comprehension, fainting
Muscular: muscle cramps, weakness, incoordination, pain
Psychiatric: abnormal thinking, hallucinations (visual or auditory), desire to hurt self or others, inappropriate crying or laughing, depression

Reprinted with permission by the Author from Healthline.com