acrocyanosis: A bluish or purplish discoloration of the hands, feet, and distal parts of the face caused by disruptions in circulation. This condition is typically caused by decreased oxygenation to the tissues.

acute tubular necrosis (ATN): A medical condition characterized by damage to the tubules in the kidney. ATN often results in acute kidney failure.

airway obstruction: A partial or complete blockage of any of the breathing passages that lead to the lungs. Airway obstruction is usually classified as either upper or lower obstruction and can occur due to mechanical or disease-specific causes.

alternative airway: An adjunct often used to ensure that the newborn is adequately ventilated. In the neonate, the alternative airways typically used include the endotracheal tube or laryngeal mask.

alveolar sacs: The end of the alveolar ducts that become the alveoli in the lungs. These sacs are small collections of air in the lungs where capillary O2 and CO2 exchange takes place.

amniotic fluid: The fluid surrounding the fetus in the amniotic sac. This fluid protects the fetus and provides a medium for the exchange of nutrients and waste between the fetus and the maternal circulation.

anaerobic respiration: Respiration that occurs in the absence of oxygen. This process oxidizes nutrients to generate energy that can be used by the cell.

antepartum: The time period before the birth of the infant.

anteroposterior diameter: The diameter of the infant’s chest measured at the nipple line. This measurement is used in determining the depth of compressions during CPR. For the neonate, this depth is defined as 1/3 of the AP diameter of the chest.

apnea: A temporary cessation of breathing that results in no movement of air into or out of the lungs. 

arrhythmia: An abnormal heart rhythm. In the infant, PEA and bradycardia are the most common arrhythmias.

aseptic technique: The technique used during medical procedures to minimize the introduction of bacteria and viruses into the environment. It differs from sterile technique in that sterile technique is used to keep all microorganisms out of the field during a procedure. 

autonomy: The ethical principle that the provider must respect an individual’s right to make choices. For the fetus and neonate, autonomy resides in the parent(s).

Ballard Maturational Assessment score: A commonly used technique to assess the gestational age of the neonate. The scored elements include both neurological and physical criteria.

beneficence: The ethical principle that the provider must act for the benefit of the patient. 

bradycardia: An abnormally slow heart rate for the individual’s age. In the neonate, a sustained rate < 100 beats per minute is considered bradycardia.

caput succedaneum: Swelling of the newborn’s scalp that is usually caused by pressure on the head during the labor and delivery process. It is typically a harmless condition.

carbon dioxide detector: A device that detects CO2 in the airway and used to prevent the accumulation of excessive levels of CO2 in the systemic circulation.

carbon dioxide (CO2): Carbon dioxide is a colorless gas that is a byproduct of respiration and is given off by the body during normal expiration.

cardiac arrest: The sudden cessation of heart function. In the neonatal population, a cardiac arrest is rarely a primary event but is usually the result of deteriorating respiratory function leading to respiratory failure, which progresses to cardiac arrest. This condition is often called cardiopulmonary arrest or failure.

carina: The junction or bifurcation between the two mainstem bronchi, one of which leads to each lung.

central cyanosis: Bluish or purplish discoloration of the lips and mucous membranes. Central cyanosis can be caused by respiratory insufficiency/failure or certain congenital cardiac malformations and is a manifestation of decreased oxygen in the blood.

choanal atresia: A congenital abnormality in which the nasal airway is obstructed by bony growth. The choana is located in the back of the nasal passage. This abnormality is caused by the failed recanalization of the nasal passage during intrauterine fetal development. 

closed-loop communication: A communication technique that involves the sender giving a message that is repeated back by the individual receiving the message. If the receiver’s message is correct, the original sender responds with a confirmatory message. 

compressed gas: Stored air or oxygen that is maintained at a pressure greater than atmospheric pressure. These gasses can be stored in cylinders or a larger tank at a facility.

congenital diaphragmatic hernia: A defect in the diaphragm allows abdominal contents to move into the thoracic cavity, causing compression of the lungs and other mediastinal structures.

congenital heart disease: An abnormality or structural defect in the heart that is formed during fetal development and present before birth. These conditions may result in arrhythmias, cyanosis, respiratory problems, or fatigue.

continuous positive airway pressure (CPAP): A form of ventilation that applies continuous air pressure throughout the respiratory cycle to keep airways open even during expiration. It improves oxygenation and is typically used in infants who can breathe on their own.

coronary arteries: The blood vessels that supply blood to the myocardium. The two large arteries are the left main and the right coronary arteries. The left main further divides into the left anterior descending artery that supplies blood to the left ventricle and atrium and the circumflex artery that circles the heart and supplies blood to the outside and back of the heart. 

crystalloid fluids: Fluids that are isotonic and capable of easily passing through semipermeable membranes. In infants, the most frequently used crystalloids are normal saline (with a concentration of 0.9% sodium chloride) and Ringer lactate. If large fluid volumes are required for replacement of fluid losses, Ringer lactate is often the fluid of choice.

cyanosis: A bluish or purplish discoloration of the skin due to decreased oxygen in the blood. See acrocyanosis and central cyanosis.

decelerations: A slowing of the fetal heart rate that may occur during uterine contractions. Prolonged or reoccurring decelerations may indicate fetal hypoxia. If the decelerations suggest that the infant is compromised, the physician will often elect to do a cesarean section, and the resuscitation team should be readily available.

delayed cord clamping (DCC): The decision to delay clamping the umbilical cord for 30–60 seconds after delivery to allow blood from the placenta to pass to the neonate. This is a controversial procedure for an infant who might require resuscitation. However, in infants who do not require resuscitation, delayed cord clamping may result in higher blood pressure, reduced incidence of intraventricular hemorrhage, enterocolitis, and need for blood transfusions. Some neonates experience elevated bilirubin levels after delayed cord clamping, necessitating phototherapy.

DOPE: Mnemonic used to remind the team of possible causes of respiratory deterioration after intubation (displaced ET tube, obstructed ET tube, pneumothorax, equipment failure).

ductus arteriosus: One of two shunts during fetal life that allows blood to bypass the fluid-filled pulmonary circulation. It is a blood vessel connecting the pulmonary artery to the descending aorta. Usually, this structure closes at birth. When it fails to close, it leads to the condition called patent ductus arteriosus with a resulting left-to-right shunt. The result is pulmonary hypertension and cardiac arrhythmias.

E-C technique: A one-handed technique for holding a face mask on the infant during ventilation. In this technique, the thumb and index finger form a “C” over the top and bottom of the mask, and the other three fingers form an “E” by holding the infant’s mandible.

edema: An abnormal collection of fluid in the soft tissues resulting in swelling. In adults, it usually appears in the lower extremities. In the fetus, edema in fetal compartments (abdominal, pleural, or pericardial) is a severe condition that can be fatal.

electrocardiogram (ECG): A noninvasive recording of the electrical activity of the heart. Electrodes are placed in specific locations on the neonate’s skin to record activity in all areas of the heart.

endotracheal intubation: Also called tracheal intubation, the placement of a plastic tube into the trachea to keep the infant’s airway open, provide ventilation and oxygenation, and administer epinephrine during resuscitation. In the infant, endotracheal intubation is always done through the mouth. 

epiglottis: An elastic cartilage shaped like a flap that overlies the glottis.

epinephrine: A naturally occurring hormone that aids in the regulation of the sympathetic autonomic nervous system. As a powerful vasopressor, epinephrine (or adrenaline) increases blood pressure, heart rate, and cardiac output. In infant resuscitation, epinephrine is used as a cardiac stimulant to treat persistent bradycardia.

esophagus: A passageway between the mouth and stomach. The esophagus is located next to the trachea and bronchi.

extracorporeal membrane oxygenation (ECMO): A machine used to replace the work of the heart and lungs in seriously ill patients whose lungs are failing to keep up with the body’s needs. It removes carbon dioxide from the blood and replaces it with oxygen.

ET tube: A plastic tube used in the endotracheal intubation procedure to keep the airway patent.

fetus: The developing infant in the uterus. At the time of delivery, the fetus is known as a neonate.

flow-inflating bag: One of the two types of manual ventilation bags, the flow-inflating bag requires a constant flow of air into the bag. This bag is a good choice for neonates since the provider can maintain control of tidal volume. Also, see self-inflating bag.

flowmeter: An instrument that measures and regulates the rate of flow of oxygen or other compressed gasses. 

foramen ovale: One of two shunts that allows blood to enter the left atrium from the right atrium during fetal life since the lungs are not functional. Typically, this shunt closes at birth when the newly born takes the first breath. The lungs are exposed to oxygen and begin to function, increasing the left atrial pressure and causing closure of the shunt.

functional residual capacity (FRC): The amount of air left in the lungs at the end of passive expiration. During passive expiration, the lungs and chest wall are in equilibrium, and there is no pressure on the respiratory muscles. The air remaining in the lungs makes it easier to fill them with the next inspiration. If inhalation and exhalation are not in balance, the neonate will have a reduced ability to absorb oxygen or remove carbon dioxide.

gasping: Abnormal respiratory effort in which the infant attempts to inhale or exhale with quick ineffective breaths. The clinician should immediately intervene to provide adequate ventilation.

gestation: Time from the last menstrual period to delivery of the infant. A full-term gestation refers to an infant born at 39 to 40 weeks (or about 280 days). Preterm delivery refers to any delivery before 37 weeks gestation. Early term gestation refers to 37–38 weeks gestation. Late-term gestation refers to a 41-week delivery. Post-term refers to gestation and delivery at 42 weeks and later.

gestational age: The age of a fetus based on the mother’s last menstrual period or uterine sonogram. When the last menstrual period is used, the provider will typically add 14 days to the age to account for the unknown time of fertilization of the egg.

glottis: An opening of the larynx, a passageway into the trachea.

hematocrit: Also known as packed cell volume or erythrocyte volume fraction, it is the volume percentage of red blood cells in the blood. In the neonate, the normal range is between 55% and 68%. 

hyperkalemia: Higher than normal potassium level. Normal neonatal potassium level is between 4.1 and 5.3 millimoles per liter. Hyperkalemia is a normal variation in extremely premature infants.

hyperoxia: A condition in which there is a greater than normal oxygen content in the blood and other tissues.

hyperthermia: A higher than normal temperature. Normal neonatal temperature is 97.7 to 99.5 degrees Fahrenheit (36.5 to 37.5 degrees Centigrade).

hypocalcemia: A lower than normal calcium level. Hypocalcemia in the neonate is defined as < 7 mg per deciliter.

hypoglycemia: A lower than normal blood glucose level. Hypoglycemia in the neonate is defined as < 30 mg per deciliter in the first 24 hours after delivery.

hyponatremia: A lower than normal sodium level. Typically, abnormal sodium levels are not treated in the first 24 hours after delivery, particularly in a premature infant. Hyponatremia is defined as serum sodium < 130 mEq/L. 

hypotension: A lower than normal blood pressure. In the neonate, hypotension is defined as a clinical condition caused by low arterial blood pressure that affects organ perfusion. Typically, severe hypotension is treated with the administration of increased fluid or blood.

hypothermia: A lower than normal temperature. Normal neonatal temperature is 97.7 to 99.5 degrees Fahrenheit (36.5 to 37.5 degrees Centigrade).

hypovolemia: A lower than normal blood volume. Normal neonatal blood volume is approximately 80–85 mL/kg of body weight. Hypovolemia in neonates is typically caused by blood loss before and during delivery.

hypoxemic ischemic encephalopathy (HIE): A condition resulting from poor brain perfusion due to hypotension, hypoxemia, or metabolic acidosis.

hypoxia: Inadequate oxygen supply at the tissue level to meet the metabolic demands of the infant. Causes of hypoxia can include pulmonary disease, congenital heart disease, airway obstruction, and sepsis. Hypoxia will often lead to respiratory distress and hyperventilation. 

iatrogenic: A medical condition or illness caused by medical procedures or treatment

inspiratory time: The time duration of inhalation. In a ventilated infant, it is the amount of time to deliver the tidal volume to the lung. 

intraosseous (IO) access: Circulatory access through the bone marrow when the umbilical vein or other IV access is not readily available. In the case of cardiac arrest, IO access is a quick and easy way to establish circulatory access. It is contraindicated if there is a long-bone fracture in the extremity. 

intrapartum: During the time of delivery.

intravenous (IV) access: Circulatory access through a vein. Due to the small size of the veins in a neonate, this route is less commonly used than IO or umbilical vein access.

intraventricular hemorrhage: Bleeding into the ventricles of the brain; most common in cases of premature birth, particularly in the presence of respiratory distress and unstable blood pressure; frequently occurs in the first several days following birth and is relatively uncommon after the first month of life.

justice: The ethical principle that the provider must treat patients and families truthfully and fairly. For the fetus and neonate, autonomy resides in the parent(s).

laryngeal mask: A supraglottal airway that keeps the infant’s airway open. Easier to insert than an endotracheal tube, the laryngeal mask helps to ensure an airtight seal on top of the glottis.

laryngoscope: A type of endoscope used to visualize the larynx. In the neonatal population, the laryngoscope is typically a rigid instrument equipped with a light that illuminates the vocal cords.

larynx: An anatomical segment that connects the pharynx and the trachea.

left-to-right shunt: A condition that results when blood from the left side of the heart enters the right side due to a ventricular or atrial septal defect. It is more common than the right-to-left shunt.

main bronchi: Major air passageway leading to the right and left lungs.

manometer: A tool for measuring pressure and vacuum. Traditionally, the manometer included a column of fluid that measured the pressure, but the term is now applied to any instrument that measures pressures.

meconium: The viscous dark green, brown, or yellow stool of a neonate composed of any material ingested by the fetus before birth. Meconium is generally all passed by the infant in the first few days after birth.

meconium aspiration syndrome: A condition that occurs when the infant is born after passing meconium in the amniotic fluid and then breathing in the fluid before or during a difficult delivery. It is the leading cause of morbidity and mortality in newborns.

metabolic acidosis: An acid-base disturbance that results in a low serum pH. If caused by sepsis or other forms of shock, metabolic acidosis may be life-threatening.

1. MR. SOPA: A mnemonic that outlines the procedure the team should follow when the newborn is not responding to treatment within 30 seconds. The mnemonic stands for mask adjustment, reposition airway, suction mouth and nose, open mouth, pressure increase, alternative airway.

myocardium: The thick middle layer of the heart wall that contains primarily contractile muscle cells.

nasal-tragus length (NTL): The distance between the baby’s nasal septum and the tragus of the ear plus 1 centimeter.

Neonatal intensive care unit (NICU): A specialty unit in the hospital created specifically to treat premature or ill newborn infants.

Neonatal Resuscitation: An educational program that focuses on resuscitation skills for the newborn.

neonate: An infant during the initial hospitalization after birth. Also known as a newborn.

newly born: An infant at the time of birth.

nonmaleficence: The ethical principle that the provider must avoid doing harm. For the fetus and neonate, autonomy resides in the parent(s).

normothermia: A normal body temperature. For the newborn, the normal range is 97.7 to 99.5 degrees Fahrenheit (36.5 to 37.5 degrees Centigrade).

 

orogastric (OG) tube: A small tube placed through the mouth that passes through the esophagus to the stomach. It can be used for feedings, medication, or suction to decompress the stomach.

oxygen: The chemical element that is often specified as O2. Room air contains approximately 21% oxygen at sea level. Recommendations are to begin resuscitation at room air and then titrate oxygen delivery based on pulse oximetry.

oxygen blender: A device that mixes oxygen with compressed air. This device allows the clinician to deliver less than 100% oxygen but greater than room air (21% oxygen).

oxygen saturation: The percentage of oxygen-rich hemoglobin relative to the total hemoglobin. At the time of birth, all infants will have an oxygen saturation < 70%. Within the first 10 minutes, the normal neonate’s oxygen saturation should be 85–95%.

passive oxygen insufflation: Using an oropharyngeal airway with high-flow oxygen by nonrebreather mask. This technique is an alternative to bag-mask ventilation. Studies show that this method has outcomes comparable to or better than the more invasive ventilation techniques.

peak inspiratory pressure (PIP): The highest pressure in the lungs during the inspiratory phase. Studies have shown that infants who require high peak inspiratory pressures during mechanical ventilation are more likely to die subsequently of respiratory causes.

persistent pulmonary hypertension (PPHN): A condition in which the normal circulatory transition at birth fails, resulting in high pulmonary pressures that cause hypoxemia. It is considered a life-threatening emergency in the neonate that must be treated aggressively.

petechiae: Small red, brown, or purple spots on the skin caused by bleeding under the skin. This disorder is common in the newborn, particularly if there has been a local increase in venous pressure during delivery.

placenta previa: A condition in pregnant women in which the placenta grows low in the uterus and may even cover the cervix. Some women may have no symptoms at all, but others may have bleeding as the fetus grows. The condition may also result in premature contractions. 

placenta: The circular, blood-filled organ in the maternal uterus that provides blood and nutrients to the fetus and removes wastes through the umbilical cord. 

placental abruption: A condition in the pregnant woman in which the placenta separates from the wall of the uterus before delivery occurs. This condition causes painful bleeding with back and abdominal pain. Depending on the degree of separation, a cesarean section might be required.

pleural effusion: An abnormal collection of fluid in the pleural space. Although relatively uncommon in the neonate, the disorder can be caused by heart failure. The most common complication is respiratory failure.

pneumonia: Although relatively uncommon in the neonate, pneumonia is typically part of sepsis syndrome. It is a serious condition that must be treated aggressively with antibiotics and fluids.

pneumothorax: A condition in which a lung is partially or completely collapsed. In the neonatal population, this is typically a complication of a premature birth since the infant does not have enough surfactant to help the lungs remain inflated. Another common cause is over-inflation of the lungs from aggressive ventilation that causes the alveoli to rupture.

positive end-expiratory pressure (PEEP): A form of ventilation that applies air pressure at the end of exhalation in the respiratory cycle to keep airways from collapsing. 

positive pressure ventilation (PPV): Technique of artificial respiration using a mechanical ventilator to force air into the infant’s lungs when spontaneous breathing is either inadequate or absent. PPV is administered through a tube to expand the lungs. When the ventilator breath stops, the passive recoil of the chest occurs, causing exhalation. PPV is accomplished by volume cycled ventilators (those that terminate the inspiration at a preset volume), pressure cycled ventilators (those that terminate the inspiration at a preset pressure), or time cycled ventilators (those that terminate the inspiration at a preset time).  

preductal: The part of the aorta closest to the aortic opening of the ductus arteriosus.

pulmonary hypoplasia: Incomplete development of the lungs due to a congenital malformation. Pulmonary hypoplasia results in a reduced number or size of pulmonary cells, segments, or alveoli. These abnormalities result in diminished or impaired gas exchange. They are often associated with other cardiac, GI, GU, or skeletal malformations. Pulmonary hypoplasia can lead to acute or chronic respiratory distress or, in severe cases, neonatal death.

pulse oximetry: The measurement of oxygen through the skin. Pulse oximetry should always be available and utilized when resuscitation is anticipated or while supplementary oxygen or PPV is administered after birth. Studies show no benefit to resuscitation with high oxygen concentrations (> 65%) as compared to low concentrations (21–30%).

pulseless electrical activity (PEA): A common arrhythmia during resuscitation in which the cardiac monitor shows electrical activity without palpable pulses in the infant. In this situation, defibrillation is not the treatment of choice. Instead, the team must continue CPR and quickly identify the cause of the arrest from the Hs and Ts. The most common cause of PEA in the neonatal population is hypoxemia.

radiant warmer: A warming device used immediately after delivery that provides the required warmth and easy access to the infant by the resuscitation team. One of the most serious complications of the device is hyperthermia. Thus, the team must understand the safe use of the device, including proper placement and use of the sensor probe.

red blood cells (RBCs): The component of blood that contains hemoglobin and iron, the elements that are essential for carrying oxygen and carbon dioxide to and from the cells. Produced by the bone marrow, the life expectancy of a red blood cell is approximately 120 days. Anemia in newborns is seen as low hemoglobin and hematocrit and an abnormal reticulocyte count (percent of immature red blood cells in the blood).

renal failure: Relatively uncommon in newborns, renal disorders can be classified as congenital or acquired. The risk of renal disorder is higher in cases of maternal diabetes or maternal drug or alcohol use. Prenatal ultrasound can often detect obstructive uropathy or renal agenesis associated with pulmonary hypoplasia. Symptoms of renal disease may include a single umbilical artery, hypospadias, abdominal mass, urinary ascites, enlarged bladder, hypertension, anuria, and oliguria.

respiratory distress: In infants, respiratory distress is often seen in the premature neonate. The primary cause is a lack of lung development and surfactant. Without surfactant, the alveoli of the lungs deflate and are increasingly hard to inflate. Although uncommon in term infants after 39 weeks gestation, respiratory distress in this population is typically due to congenital abnormalities, a very rapid labor, or problems during delivery that reduce blood flow to the infant. 

respiratory failure: This occurs in the neonate when the gas exchange between the air and the blood cannot match the metabolic demands of the body. Respiratory failure is the most common cause of morbidity and mortality in the neonatal population. Signs and symptoms of impending respiratory failure include bradypnea or tachypnea, tachycardia or bradycardia, hypertension, stridor, diminished breath sounds, paradoxical chest wall movement, wheezing, and the use of accessory muscles during respiration.

right-to-left shunt: A cardiac defect that causes deoxygenated blood from the right side of the heart to pass into the left side without going through the pulmonary circulation. This shunt causes hypoxemia that results in the characteristic bluish discoloration of the skin.

Robin sequence: A congenital malformation marked by an underdeveloped mandible. The abnormality causes the tongue of the newborn to obstruct the pharynx. 

self-inflating bag: One of the two types of manual ventilation bag, the self-inflating bag refills itself when the provider stops squeezing the bag. Also, see flow-inflating bag.

sepsis: A potentially fatal response to infection that, without treatment, will lead to organ failure and death. The Sepsis Alliance defines the TIME acronym to remember potential signs and symptoms: temperature (although fever is not always apparent), infection, mental decline, extremely ill.

sniffing position: The optimal position for intubation in which the pharyngeal and laryngeal axes align, making the trachea relatively straight. It is called the sniffing position because it mimics how an individual tilts the head back slightly. This position is contraindicated if cervical spine injury is a possibility.

subcutaneous fat: The layer of fat that lies just under the dermis layer. Particularly critical in the newborn, this layer of fat helps to insulate the body and stores energy.

suction equipment: Including the catheter and machine, suction equipment is used to clear the airway of secretions. A bulb syringe might be used for initial suctioning of the healthy newborn. 

survival reflex: The newborn has several reflexes that are innate and help provide some control of the body. These include the rooting reflex, the Moro reflex, the stepping reflex, the grasp reflex, the tonic neck reflex, the righting reflex, the tongue-thrust reflex, and the withdrawal reflex. These primitive reflexes disappear over time as the infant grows and learns to control his body.

tachycardia: An abnormally high heart rate. In the newborn, the heart rate normally varies with activity. A faster than normal heart rate in the neonate can be caused by conditions such as infection, illness, fever, and medications.

tachypnea: An abnormally high respiratory rate (typically > 30–60 breaths per minute in the newborn). A frequent finding in the premature infant, it is also common in neonates born by cesarean section or to a mother with diabetes. Tachypnea is a sign of impending respiratory failure, so it should be monitored and treated.

therapeutic hypothermia: Lowering the core temperature using cooling devices. It is typically initiated after cardiac arrest to shunt blood from the periphery to the vital organs (brain, heart, and lungs). The temperature is usually lowered to 89–93 degrees Fahrenheit (32–34 degrees Centigrade) and maintained for 24 hours or less.

thoracentesis: A procedure where a catheter is inserted into the pleural space to remove air or fluid inside the thoracic cavity.

thrombocytopenia: One of the most common hematological disorders in neonates, affecting almost 25% of infants admitted to the NICU. It is categorized as early or late, and treatment for the neonate is a transfusion of platelets to correct the deficit.

thyroid cartilage: A thick cartilage surrounding the larynx to protect it.

T-piece resuscitator: The device that consistently provides inflation pressures at the target pressure and longer inspiratory times.

trachea: The segment of airway between the larynx and the carina.

transillumination of the chest: A screening test for pneumothorax. A high-intensity light is directed toward the newborn’s chest. The brightest side of the infant’s chest is the side of the suspected pneumothorax.

transitional circulation: The change of the circulatory system from the fetal and maternal circulation to that of the neonate. Usually, the changes happen smoothly, but the team must monitor the infant requiring resuscitation to ensure that the transition occurs, or appropriate interventions must be implemented. During this transition, the umbilical cord is clamped, and the placenta is no longer the blood reservoir. Blood flow increases to the heart and lungs, and the foramen ovale closes. After birth, blood flow reverses through the ductus arteriosus and arterial blood oxygen increases, resulting in the gradual closure of the ductus arteriosus. 

umbilical cord prolapse: A complication in which the umbilical cord drops through the open cervix and into the birth canal before or during delivery. This can cause compression of the cord and reduced blood and oxygen flow from the placenta to the fetus. One of the major signs of this complication is a decrease in the fetal heart rate, sometimes referred to as variable decelerations. Prolonged compression can result in fetal hypoxia and brain damage.

umbilical vein: The umbilical cord vein that carries blood and oxygen from the placenta into the fetus. This vessel is catheterized if blood or other volume expanders must be administered to the fetus after birth. 

umbilical vein catheterization: Insertion of a catheter through the umbilical vein in the umbilical cord to infuse volume expanders or medications during neonatal resuscitation.

vallecula: A pouch located at the base of the tongue and the epiglottis.

variable decelerations: A decrease in the fetal heart rate to < 115 beats per minute that lasts > 15 seconds and < 10 minutes. These decelerations are often caused by umbilical cord compression that reduces blood and oxygen flow to the fetus. 

vocal cords: Two membranous tissues at opposite locations in the larynx that project medially from the laryngeal walls, forming a slit across the glottis. The edges of the vocal folds vibrate when an airstream passes through, causing modulation to produce the voice.

volume expanders: When blood loss is known or suspected and the neonate is symptomatic (heart rate not responding to other measures), these can be used to increase volume. Isotonic crystalloid solutions or blood products are the most frequently used products for volume expansion.