June 04, 2010 01:43am EST 

Those who visit a hospital emergency room for the first time may not know what to expect when they first meet the emergency physician. The emergency room is a place where every second lost is a second that could have been used to save another, making every second count.
That being said, the job of the emergency physician is tough. Responsible for quick diagnoses and intuitive treatments, the emergency physician must see a patient, gather the right information, and prescribe the correct treatment. Emergency physicians are also specialists, requiring a three-to-four-year residency program devoted to acute care before practicing in the emergency room.
Assisting the emergency physician is the emergency room physician assistant, responsible for providing diagnostic, therapeutic, and preventive health care services. They are also responsible for ordering and interpreting laboratory tests and making diagnoses.
Diagnostic tests acts as a tool for determining symptoms and a subsequent diagnosis. In hospital emergency rooms, diagnostic tests and their accuracy, relevance, and timeliness are integral to the success of the physicians. For first time visitors to the hospital emergency room, these tests may be confusing and frightening. Here is a list of common diagnostic tests found in the hospital emergency room, and what they may say about your health:
Urine sample: This simple tests find urinary infections and screen for metabolic conditions, such as diabetes. It also confirms pregnancy and diagnoses dehydration.
Blood test: Blood tests are used to identify infections, look at blood counts, analyze blood clots, and determine electrolyte composition of bodily fluids. Doing so can determine whether or not a hospital patient is dehydrated or low on sodium or potassium. At times, a blood test will be ordered to target a specific organs or confirm diagnoses.
EGG or EKG: An EGG or EKG, or electrocardiogram, uses electrodes placed on the arms, legs, and chest to record the electrical activity of the heart. An EKG spots signs of cardiac problems, such as heart failure or irregular heart rhythm.
X-ray: X-rays are a form of electromagnetic radiation used for medical imaging. They are often used to diagnose lung and heart disease, pneumonia, heart failure, broken bones, degenerative joint disease, and internal trauma.
CT scan: A CT scan, or computer tomography, uses high-dose ionized radiation to provide a three-dimensional picture of a patient. During a CT scan, a hospital patient is placed inside a machine while an x-ray tube rotates around the body. They are used to diagnose bone tumors, cancers, and fractures; as well as detect internal injuries and bleeding. CT scans can also find the exact location of an infection, tumor, or blood clot. These tests are only ordered in specific circumstances as they are expensive and may force an overexposure to radiation on the patient.
MRI: A magnetic resonance image uses strong magnets and radio waves to create a picture of the inside of the body. MRIs are used to find tumors, bleeding, blood vessel diseases, infections, and bone and organ damage in different areas of the body, including chest, head, bones, spine and more.