PCEP BOOK 4: SPECIALIZED NEWBORN CARE 212 Alpha fetoprotein: A normal fetal serum protein. When a fetus has an open neural tube defect, such as anencephaly or meningomyelocele, increased amounts of this protein pass into the amniotic fluid and the pregnant woman’s blood, thus providing the basis for an antenatal screening test. Low or high maternal serum alpha fetoprotein levels may also indicate certain other fetal chromosomal defects or congenital malformations. ALT: Alanine transaminase. The serum level of this enzyme is used as a measure of liver function. When liver cells are destroyed by disease or trauma, transaminases are released into the bloodstream. The higher the ALT, the greater the number of destroyed or damaged liver cells. Alveoli: The numerous, small, saclike structures in the lungs where the exchange of oxygen and carbon dioxide between the lungs and blood takes place. Amniocentesis: A procedure used to obtain amniotic fluid for tests to determine genetic makeup, health, or maturity of the fetus. Using ultrasound guidance, a needle is inserted through a pregnant woman’s abdominal wall and into the uterus where a sample of amniotic fluid is withdrawn, usually at 16 to 20 weeks’ gestation. If done earlier (11–13 weeks), there is often insufficient amniotic fluid and the complication rate is higher. Amnioinfusion: Infusion of fluid into the amniotic cavity. Amnioinfusion may be done by either of the following procedures: after membranes have ruptured, by passing a catheter through the cervix and into the uterus and infusing physiologic (normal) saline solution or otherwise by infusing saline through an amniocentesis needle placed through the maternal abdominal wall and into the uterus. Amnioinfusion may be used to reduce cord compression (as indicated by variable fetal heart rate decelerations) during labor when oligohydramnios is present. Amnion: The inner membrane surrounding the fetus. The amnion lines the chorion but is separate from it. Together these membranes contain the fetus and amniotic fluid. Amniotic fluid: Fluid that surrounds the fetus and makes up the “water” in the “bag of waters.” It provides a liquid environment in which the fetus can grow freely and serves as insulation, protecting the fetus from temperature changes. It also protects the fetus from a blow to the uterus by distributing equally in all directions any force applied to the uterus. Amniotic fluid is composed mainly of fetal urine, but also contains cells from the fetus’s skin and chemical compounds from the fetus’s respiratory passages. Amniotic fluid analysis: Evaluation of various compounds in the amniotic fluid that relate to fetal lung maturity and fetal health. Fetal skin cells that normally float in the amniotic fluid may also be obtained with amniocentesis and grown in a culture to allow determination of fetal chromosomal status. Amniotic fluid embolism: Amniotic fluid that escapes into the maternal circulation, usually late in labor or immediately postpartum. Rather than causing a mechanical blockage in the circulation as emboli of other origin might do, amniotic fluid embolism is thought to cause an anaphylactic-type response in sus- ceptible women. This response is dramatic and severe, with sudden onset of hypoxia and hypotension. Seizures or cardiac arrest may occur. If a woman survives the initial phase, disseminated intravascular coagulation often follows. Although rare, it is associated with a high maternal mortality rate. Analgesia: Relative relief of pain without loss of consciousness. Administration of specific medications is the most common way to provide analgesia. Anemia: Abnormally low number of red blood cells. The red blood cells may be lost because of bleeding, destroyed because of disease process, or produced in insufficient numbers. Anemia is determined by measuring the hemoglobin or hematocrit. Anencephaly: A lethal congenital defect of neural tube development in which there is partial or complete absence of the skull and brain. Anesthesia: Total relief of pain, with or without loss of consciousness. Usually requires more invasive techniques than that required for analgesia. General inhalation anesthesia produces loss of conscious- ness, while major conduction anesthesia, such as spinal or epidural injection of long-lasting local anes- thetics, produces total loss of pain in a specific area of the body without loss of consciousness. 10-Glossary_BKIV_PCEP_211-244.indd 212 5/29/21 8:06 AM
Previous Page Next Page