Neonatal Respiratory Distress Syndrome
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Transcript of Neonatal Respiratory Distress Syndrome
Neonatal Respiratory Distress SyndromeNeonatal respiratory distress syndrome (RDS, formerly termed as hyaline membrane disease, most often
occurs in preterm infants, infants of diabetic mothers, infants born by cesarean birth, or those for any reason have decreased perfusion of the lungs. The pathologic feature of RDS is a hyaline-like membrane formed from exudates of an infant’s blood that begins to line the terminal bronchioles, alveolar ducts and the alveoli. This membrane prevents exchange of oxygen and carbon dioxide at the alveolar- capillary membrane. The cause of RDS is a low level of absence of surfactant that normally lines the alveoli and reduces surface tension on expiration to keep the alveoli from collapsing on expiration. The condition makes it difficult to breathe.
CAUSES
Neonatal RDS occurs in infants whose lungs have not yet fully developed.
The disease is mainly caused by a lack of a slippery, protective substance called surfactant, which helps the lungs inflate with air and keeps the air sacs from collapsing. This substance normally appears in fully developed lungs.
Neonatal RDS can also be the result of genetic problems with lung development.
In addition to prematurity, the following increase the risk of neonatal RDS:
A brother or sister who had RDS Diabetes in the mother
Cesarean delivery
Delivery complications that reduce blood flow to the baby
Multiple pregnancy (twins or more)
Rapid labor
The risk of neonatal RDS may be decreased if the pregnant mother has chronic, pregnancy-related high blood pressure or prolonged rupture of membranes, because the stress of these situations can cause the infant's lungs to mature sooner.
PATHOPHYSIOLOGY
Risk factors
A brother or sister who had RDSDiabetes in the motherCesarean delivery
Reduced perfusion to the lungs Multiple pregnancy Rapid labor
Increased cardiac rate Venous vasoconstriction
Central blood redistribution
Acidosis
Increased cardiac work load
Increased respiratory rate
Increased in size of right ventricle
Blood regurgitates to systemic circulation
Edema
Decreased urine output
Decreased cardiac output
Aerobic respiration shifts to anaerobic
respiration
Lactic acid as a byproduct of anaerobic respiration
Hyaline membrane formation
Nasal flaring, expiratory grunting, chest retractions
Decreased cardiac filling time
Absence or decreased surfactant production
Decreased lung compliance
Shunting
Ductus areteriosus and foramen ovale
remains open
Pulmonary hypertension
Poor perfusion
Increased work of breathing
Alveolar dead space
Haziness seen in chest x-ray
Tissue hypoxia
Increase oxygen demand
Poor O2 and CO2 exchange
Tissue injury
Activation of the inflammatory
process
Carbon dioxide
accumulationCyanotic mucous membrane
Apnea
Increased surface tension in alveoli
Decreased functional residual capacity
Heart failure
High pressure is required to fill the lungs with air for the first time. Id alveoli collapse with each expiration, forceful inspirations are required to inflate them.
With deficient surfactant, areas of hypoinflation begin to occur and pulmonary resistance increases. Blood then shunts through the foramen ovale and the ductus arteriosus as it did during fetal life. The lungs are poorly perfused, affecting gas exchange. As a result, the production of surfactant decreases even further.
The poor exchange leads to tissue hypoxia which causes the release of lactic acid. This, combined with the increasing carbon dioxide level resulting from the formation of hyaline membrane on the alveolar surface, leads to severe acidosis. Acidosis causes venous vasoconstriction which leads to poor perfusion further compounding the ill surfactant production. In addition, vasoconstriction causes blood to shunt centrally increasing the workload of the heart.
EXAMS AND TESTS
Blood culture - may indicate bacteremia. Not helpful initially because results may take >48 hours
Blood gas - used to assess degree of hypoxemia if arterial sampling, or acid/base status if capillary
sampling
Chest radiography
Complete blood count with differential
Leukocytosis or bandemia indicates stress or infection
Neutropenia correlates with bacterial infection
Low hemoglobin level shows anemia
High hemoglobin level occurs in polycythemia
Low platelet level occurs in sepsis
Lumbar puncture - if meningitis is suspected
Pulse oximetry - used to detect hypoxia and need for oxygen supplementation
THERAPEUTIC MANAGEMENT
Surfactant Therapy
Surfactant can be given to help the air sacs in the lungs expand and take in more oxygen. There are two options, both of which are delivered directly into the baby's windpipe. One type of surfactant comes from cows and the other is synthetic. As the surfactant takes effect, use of the respirator can gradually be reduced.
Muscle Relaxants
Pancuronium (Pavulon) abolishes spontaneous respiratory action, therefore allowing mechanical ventilation to be accomplished at lower pressures because there is no normal muscle resistance to overcome.
Mechanical Respirator
A mechanical respirator is used to keep the air sacs from collapsing and to improve the exchange of oxygen and other gases in the lungs. This treatment helps the baby breathe better and is almost always required in severe RDS. High-frequency ventilation may be used to reduce lung injury.
A breathing machine can be lifesaving, especially for babies with the following:
High levels of carbon dioxide in the arteries Low blood oxygen in the arteries
Low blood pH
Extracorporeal Membrane Oxygenation
Blood is removed from the baby by gravity using a venous catheter advanced into the right atrium of the heart. The blood circulates from the catheter to the ECMO machine, where it is oxygenated and rewarmed. It is then returned to the baby’s aortic arch by a catheter advanced through the carotid artery.
Liquid Ventilation
Liquid ventilation involves the use of perfluorocarbons, substances used in industry to assess for leakage in pipes. This helps to distend the lungs and aid in oxygen exchange.
Nitric Oxide
Nitric oxide caused pulmonary vasodilatation which can be helpful to increase blood flow to the alveoli when persistent pulmonary hypertension is present.
Nutritional Support
Newborns with RDS may be given food and water by the following means:
Tube feeding—a tube is inserted through the baby's mouth and into the stomach
Parenteral feeding—nutrients are delivered directly into a vein
It is important that all babies with RDS receive excellent supportive care, including the following, which help reduce the infant's oxygen needs:
Few disturbances Gentle handling
Maintaining ideal body temperature
Infants with RDS also need careful fluid management and close attention to other situations, such as infections, if they develop.
OUTLOOK (PROGNOSIS)
The condition often worsens for 2 to 4 days after birth with slow improvement thereafter. Some infants with severe respiratory distress syndrome will die, although this is rare on the first day of life. If it occurs, it usually happens between days 2 and 7.
Long-term complications may develop as a result of too much oxygen, high pressures delivered to the lungs, the severity of the condition itself, or periods when the brain or other organs did not receive enough oxygen.
POSSIBLE COMPLICATIONS
Air or gas may build up in:
The space surrounding the lungs (pneumothorax) The space in the chest between two lungs (pneumomediastinum)
The area between the heart and the thin sac that surrounds the heart (pneumopericardium)
Other complications may include:
Bleeding into the brain (intraventricular hemorrhage of the newborn) Bleeding into the lung (sometimes associated with surfactant use)
Delayed mental development and mental retardation associated with brain damage or bleeding
Retinopathy of prematurity and blindness
PREVENTION
Good prenatal care beginning as early as possible in pregnancy. Eat a healthful diet and take vitamins suggested by thedoctor. Do not smoke or use alcohol or drugs.
If you are at high risk of giving birth to a premature baby: Steroids administration Amniocentesis Surfactant administration right after birth
FOCUS CHARTING
Date Focus Data, Action, Response
In from EINC cuddled by Nurse Roberto
010912/5am dyspnea D: pale; c nasal flaring; c subcostal retractions
A: placed under radiant warmer
5:01 am
A: oxygen administered at 10LPM via hood; placed on moderate high back rest
5:05 am A: attended by Dr. Fancubit c orders
Marie Paz P. Hementera, RN
5:10am Admission A: condition explained to mother and mother by Dr. Fancubit; consent for admission obtained c consent form signed
A: 25cc D10 Water placed in volumetric chamber and inserted aseptically by Dr. Fabcubit thru umbilical cannulation and regulated at 3mgtts
A: 99.4cc D5 Water + 0.6 Dopamine placed in volumetric chamber and hooked as side drip and regulated at 3mgtts/min
Marie Paz P. Hementera, RN
5:30am Diagnostic procedure D: CBC APC BT
A: request and specimen sent to laboratory
Marie Paz P. Hementera, RN
5:45am Diagnostic procedure D: CXR APL + Abd
A: sent to radiology department cuddled by Nurse Villanueva accompanied by father and came back after 20 minutes
Marie Paz P. Hementera, RN
6am Hypoglycemia D: jittery, skin cold to touch, diaphoretic
6:05 am A: capillary blood glucose taken and revealed 20mg/ dl
6:05 am A: referred to Dr. Fancubit c orders
A: 2.2 cc of D10 Water given as IV bolus as ordered
6:35am R: capillary blood glucose retaken and revealed 100mg/dl
7am Endorsed for continuity of care
Marie Paz P. Hementera, RN