Perinatal asphyxia
Encyclopedia
Perinatal asphyxia or neonatal asphyxia is the medical condition resulting from deprivation of oxygen
to a newborn infant that lasts long enough during the birth process to cause physical harm, usually to the brain. Hypoxic damage can occur to most of the infant's organs (heart
, lung
s, liver
, gut
, kidneys), but brain damage
is of most concern and perhaps the least likely to quickly or completely heal. In the more pronounced cases, an infant will survive, but with damage to the brain manifested as either mental, such as developmental delay or intellectual disability
, or physical, such as spasticity
— in fact, spastic diplegia
and the other forms of cerebral palsy
almost always feature asphyxiation during the birth process as a major, if not defining, factor.
It results most commonly from a drop in maternal blood pressure
or some other substantial interference with blood flow to the infant's brain
during delivery
. This can occur due to inadequate circulation
or perfusion
, impaired respiratory effort, or inadequate ventilation
. Perinatal asphyxia happens in 2 to 10 per 1000 newborns that are born at term, and more for those that are born prematurely.
An infant suffering severe perinatal asphyxia usually has poor color (cyanosis
), perfusion, responsiveness, muscle tone, and respiratory effort, as reflected in a low 5 minute Apgar score
. Extreme degrees of asphyxia can cause cardiac arrest
and death. If resuscitation is successful, the infant is usually transferred to a neonatal intensive care unit
.
1987 saw the first book with these words in the title, by Alberto Lacoius-Petruccelli, Perinatal Asphyxia, edited by Plenum, that was recently revised in 2006 by Vantage Press.
Hypoxia (medical)
Hypoxia, or hypoxiation, is a pathological condition in which the body as a whole or a region of the body is deprived of adequate oxygen supply. Variations in arterial oxygen concentrations can be part of the normal physiology, for example, during strenuous physical exercise...
to a newborn infant that lasts long enough during the birth process to cause physical harm, usually to the brain. Hypoxic damage can occur to most of the infant's organs (heart
Heart
The heart is a myogenic muscular organ found in all animals with a circulatory system , that is responsible for pumping blood throughout the blood vessels by repeated, rhythmic contractions...
, lung
Lung
The lung is the essential respiration organ in many air-breathing animals, including most tetrapods, a few fish and a few snails. In mammals and the more complex life forms, the two lungs are located near the backbone on either side of the heart...
s, liver
Liver
The liver is a vital organ present in vertebrates and some other animals. It has a wide range of functions, including detoxification, protein synthesis, and production of biochemicals necessary for digestion...
, gut
Gut (zoology)
In zoology, the gut, also known as the alimentary canal or alimentary tract, is a tube by which bilaterian animals transfer food to the digestion organs. In large bilaterians the gut generally also has an exit, the anus, by which the animal disposes of solid wastes...
, kidneys), but brain damage
Brain damage
"Brain damage" or "brain injury" is the destruction or degeneration of brain cells. Brain injuries occur due to a wide range of internal and external factors...
is of most concern and perhaps the least likely to quickly or completely heal. In the more pronounced cases, an infant will survive, but with damage to the brain manifested as either mental, such as developmental delay or intellectual disability
Intellectual disability
Intellectual disability is a broad concept encompassing various intellectual deficits, including mental retardation , deficits too mild to properly qualify as MR, various specific conditions , and problems acquired later in life through acquired brain injuries or neurodegenerative diseases like...
, or physical, such as spasticity
Spasticity
Spasticity is a feature of altered skeletal muscle performance in muscle tone involving hypertonia, which is also referred to as an unusual "tightness" of muscles...
— in fact, spastic diplegia
Spastic diplegia
Spastic diplegia, historically known as Little's Disease, is a form of cerebral palsy that is a neuromuscular condition of hypertonia and spasticity in the muscles of the lower extremities of the human body, usually those of the legs, hips and pelvis...
and the other forms of cerebral palsy
Cerebral palsy
Cerebral palsy is an umbrella term encompassing a group of non-progressive, non-contagious motor conditions that cause physical disability in human development, chiefly in the various areas of body movement....
almost always feature asphyxiation during the birth process as a major, if not defining, factor.
It results most commonly from a drop in maternal blood pressure
Blood pressure
Blood pressure is the pressure exerted by circulating blood upon the walls of blood vessels, and is one of the principal vital signs. When used without further specification, "blood pressure" usually refers to the arterial pressure of the systemic circulation. During each heartbeat, BP varies...
or some other substantial interference with blood flow to the infant's brain
Brain
The brain is the center of the nervous system in all vertebrate and most invertebrate animals—only a few primitive invertebrates such as sponges, jellyfish, sea squirts and starfishes do not have one. It is located in the head, usually close to primary sensory apparatus such as vision, hearing,...
during delivery
Childbirth
Childbirth is the culmination of a human pregnancy or gestation period with the birth of one or more newborn infants from a woman's uterus...
. This can occur due to inadequate circulation
Circulatory system
The circulatory system is an organ system that passes nutrients , gases, hormones, blood cells, etc...
or perfusion
Perfusion
In physiology, perfusion is the process of nutritive delivery of arterial blood to a capillary bed in the biological tissue. The word is derived from the French verb "perfuser" meaning to "pour over or through."...
, impaired respiratory effort, or inadequate ventilation
Ventilation (physiology)
In respiratory physiology, ventilation is the rate at which gas enters or leaves the lung. It is categorized under the following definitions:-Sample values:...
. Perinatal asphyxia happens in 2 to 10 per 1000 newborns that are born at term, and more for those that are born prematurely.
An infant suffering severe perinatal asphyxia usually has poor color (cyanosis
Cyanosis
Cyanosis is the appearance of a blue or purple coloration of the skin or mucous membranes due to the tissues near the skin surface being low on oxygen. The onset of cyanosis is 2.5 g/dL of deoxyhemoglobin. The bluish color is more readily apparent in those with high hemoglobin counts than it is...
), perfusion, responsiveness, muscle tone, and respiratory effort, as reflected in a low 5 minute Apgar score
Apgar score
The Apgar score was devised in 1952 by the eponymous Dr. Virginia Apgar as a simple and repeatable method to quickly and summarily assess the health of newborn children immediately after birth...
. Extreme degrees of asphyxia can cause cardiac arrest
Cardiac arrest
Cardiac arrest, is the cessation of normal circulation of the blood due to failure of the heart to contract effectively...
and death. If resuscitation is successful, the infant is usually transferred to a neonatal intensive care unit
Neonatal intensive care unit
A Neonatal Intensive Care Unit —also called a Special Care Nursery, newborn intensive care unit, intensive care nursery , and special care baby unit —is an intensive care unit specializing in the care of ill or premature newborn infants.The problem of premature and congenitally ill infants is not a...
.
1987 saw the first book with these words in the title, by Alberto Lacoius-Petruccelli, Perinatal Asphyxia, edited by Plenum, that was recently revised in 2006 by Vantage Press.
External links
- Asphyxia neonatorum, School of Child and Adolescent Health, University of Cape Town