Author: Glossary

  • Sister chromatid exchange

    The exchange of corresponding parts of homologous maternal and paternal chromosomes during the first meiotic division. This contributes to genetic diversity in the offspring.  

  • Exchange

    To give up or substitute something for something else.  

  • Base excess of extracellular fluid

    The substance concentration of base in extracellular fluid determined at a pH of 7.40 and Pco2 of 40 mm Hg. Because this quantity cannot be determined directly, a model of extracellular fluid is used as a basis. The model consists of one volume of blood plus two volumes of plasma. As with the base excess…

  • Base excess of blood

    The substance concentration of base in whole blood determined at a pH of 7.40 and Pco2 of 40 mm Hg. This measurement helps one assess the relative contribution of respiratory versus metabolic components in acid-base imbalances in the blood.  

  • Excerebration

    Removal of the brain, especially that of the dead fetus to facilitate delivery.  

  • Caries excavation

    The removal of the diseased portion of a tooth, before it is filled. It may be accomplished with air, burs, chemicals, drills, lasers, ultrasound, and other means.  

  • Atrophic excavation

    A cupped appearance of the optic nerve due to atrophy of the nerve fibers.  

  • Exarticulation

    Amputation of a limb through a joint.  

  • Rectoabdominal examination

    Physical examination of the abdomen and rectum (e.g., to determine the cause of abdominal pain or to identify occult bleeding).  

  • Focused history and physical examination

    In emergency medicine, a combination of appropriate questions (i.e., sample, History, and OPQRST) and physical examination directed to the specific body system (i.e., cardiopulmonary, neurological, musculoskeletal) that an EMS provider suspects may be causing a patient’s presenting problem. The assessment is conducted after the initial assessment has been completed and differs for medical or trauma…