After the doctor has inquired carefully into the life history of the patient as related to his symptoms or his disease, a physical and laboratory examination may follow. A physical examination may vary from a casual use of inspection, palpation, auscultation, percussion and testing of reflexes, to the use of a great variety of instruments which now extend the senses of the doctor.
Inspection involves use of the eyes. The doctor can see eruptions on the skin, bumps below the surface which stretch the skin, ulcers, bruises, swellings, loss of hair or nails, redness of the throat, fluids coming from the eyes or nose or nipples of the breasts.
With his trained fingers he can feel the margin of the liver, lumps on the smooth surfaces of inner organs, organs out of place, areas of tenderness, broken bones or other disturbances.
He can hear, with his ear alone or with the aid of a stethoscope, changes in the sounds of the lungs and heart and intestines. He can thump the chest and abdomen and detect areas of fluid or solidity.
The reflexes, like the knee jerk, and reactions in the skin tell him about the integrity of the nervous system.
With a variety of instruments, he can look into the eye with the ophthalmoscope, the ear with the otoscope, the nose with the rhinoscope, the throat with the laryngoscope and the pharyngoscope, the lungs with the bronchoscope, the stomach with the gastroscope, the bladder with the cystoscope, and the rectum with the proctoscope. With the sphygmomanometer he measures the blood pressure; with the electrocardiograph he records the motions of the heart; with the basal metabolic apparatus he determines the rate of the body chemistry. The X-ray shows changes in organs and tissues far below the surface of the body. A spirometer may be used to determine the amount of air taken in by the lungs during respiration.