Retinopathy of Prematurity/ Periventricular–Intraventricular Hemorrhage

ROP is a potentially blinding retinal vascular eye disease that occurs in very-low-birth-weight and preterm infants. Supplemental oxygen, birth weight, multiple births, white race, mechanical ventilation, and early gestational age are the major risk factors for the development of ROP. The incidence of ROP in preterm newborns is inversely proportional to their birth weight. Of the approximately 4 million infants born in the United States annually, about 28,000 weigh 1,500 g (2.75 lb) or less. According to the National Eye Institute (NEI), each year an estimated 1,400 to 1,600 infants in the United States develop ROP severe enough to require medical treatment. Of these infants, 400 to 600 become legally blind annually (NEI, 2019). ROP can also lead to vitreous hemorrhage and retinal detachment, which is the major cause of visual impairment and blindness (CDC, 2019i).

Predisposing factors for the development of ROP include preterm birth, low birth weight, level of oxygen saturation, genetics, and the severity of underlying illnesses present at birth. Additionally, the level of oxygen saturation and genetics seem to play a role in the severity of ROP.

Pathophysiology

The eye begins to develop early in gestation, at approximately 16 weeks. Blood vessels begin to form and grow to supply the retina, which transmits visual information to the brain with oxygen and nutrients. These vessels continue to grow gradually until about the last 12 weeks of pregnancy (between 28 and 40 weeks’ gestation), at which time the eye undergoes rapid development. Thus, an infant born at term has retinal vessels that are almost completely developed. However, when the infant is born preterm, normal blood vessel development is interrupted. In terms of the developing retina, preterm birth interrupts the normal development of the vascular bed that will nourish the eye. The lack of blood vessels in the retina initiates anaerobic metabolism, further increasing the already existing hypoxia. Without blood flow through the eye, the retina is deprived of oxygen and its metabolic needs go unmet.

ROP typically develops in both eyes secondary to an injury such as hyperoxemia due to prolonged assistive ventilation and high oxygen exposure, acidosis, and shock. Exposure to high oxygen concentrations leads to severe retinal vasoconstriction with endothelial damage and vessel obliteration. Abnormal blood vessels develop in an attempt to nourish the retina. These vessels, which proliferate in the retina, are highly fragile and bleed easily, leading to the formation of scar tissue. They can also enlarge and twist, pulling the retina away from the wall of the eye and resulting in retinal detachment.

TAKE NOTE!

Although the precise levels of hyperoxemia that can be sustained without causing retinopathy are not known, very immature newborns who develop respiratory distress often must be given high oxygen concentrations to maintain life (Cunningham et al., 2018).

ROP is classified in five stages, ranging from mild (stage I) to severe (stage V). The grades are based on three criteria: (1) severity, (2) location by zones in the retina, and (3) extent or proportion of the retinal circumference (CDC, 2019i). The degree of abnormal blood vessel growth and evidence of retinal detachment are used to stage this disorder.

Therapeutic Management

With the increasing survival of premature infants and increased incidence of ROP, it is important to screen for ROP risk and treat at-risk clients in a timely manner to preserve their visual function and reduce complications. The key to treating ROP is prevention by minimizing the risk of preterm birth through providing quality prenatal care and health counseling to all pregnant women. When ROP does develop, treatment depends on the stage and degree of retinal findings. Typically, stages I and II resolve on their own and require only periodic evaluation by the ophthalmologist. For more advanced stages, surgical intervention such as laser photocoagulation therapy or cryotherapy can be done. Laser ablation is the most common treatment modality. A laser is directed to a designated spot to destroy abnormal vessels and seal leaks. A second method of treatment involves an injection of Avastin or Lucentis into the eye that stops the signal that is causing the abnormal vessels to form. Further research is being done to determine long-term safety and optimal dosages of injections (Coats, 2020).

Nursing Assessment

The newborn who develops ROP exhibits no signs or symptoms, so assessment involves identifying the newborn at risk. Review the maternal prenatal history for risk factors such as substance abuse, hypertension, preeclampsia, heavy cigarette smoking, or evidence of placental insufficiency. Also assess the newborn’s gestational age and weight. Be especially alert for newborns weighing 1,500 g or less or those born at 28 weeks’ gestation or less. Oxygen plays a critical role in ROP and reducing the level and length of exposure to it will reduce the incidence of ROP. Evaluate the newborn’s history for the duration of intubation and the use of oxygen therapy, IVH, and sepsis (Fanaroff & Fanaroff, 2019). Prepare the infant for an ophthalmologic examination.

Nursing Management

By integrating the most recent evidence-based practice guidelines with clinical practice management, newborn outcomes can be improved. In light of the growing body of evidence regarding ROP prevention, many NICUs have adopted lower oxygen saturation ranges for preterm infants. Oxygen saturation target ranges in the mid-80s to lower mid-90s are usually safe and can reduce the severity of ROP in newborns born before 32 weeks’ gestation. Institute measures for prevention. Administer oxygen therapy cautiously and monitor oxygen saturation levels to ensure that the lowest oxygen concentration possible is used and for the shortest possible duration. Cover the isolette with a blanket and dim the surrounding lights to protect the newborn’s eyes.

Clear evidence exists that lower oxygen saturation levels once considered insufficient are in fact safe and have fewer harmful effects (Raghuveer & Zackula, 2020). It is essential that nurses understand the evidence base on which preventive strategies are founded so they can help improve the visual outcomes for all preterm infants assigned to their care. Nurses should implement good practices such as achieving target oxygen saturation, encouraging breast-feeding, hand hygiene and asepsis to reduce infections, and nutritional support to achieve weight gain. These interventions help reduce ROP in preterm infants.

TAKE NOTE!

Any newborn with a birth weight of less than 1,500 g or born at less than 28 weeks’ gestation should be examined by a pediatric ophthalmologist within 4 to 6 weeks after birth.

Assist with scheduling an ophthalmic examination for the newborn. Expect to administer a mydriatic eye agent to dilate the newborn’s pupils approximately 1 hour prior to the examination as ordered. During this time, take extra care to protect the newborn’s eyes from bright light. If necessary, provide assistance with the examination by holding the newborn’s head. Assist with scheduling follow-up eye examinations, usually every 2 to 3 weeks depending on the severity of the clinical findings at the first examination (Kenner et al., 2019).

The American Academy of Pediatrics (AAP) has issued practice guideline recommendations for ROP screening and treatment that aid in creating a consistent and reliable ROP protocol. Newborns with ROP are at risk of developing strabismus (abnormal alignment of the eyes), nystagmus (rapid involuntary movements of the eyes), high myopia (eyeball stretches and becomes too long, which can lead to retinal detachment), and abnormal retinal structure and should therefore receive continued long-term follow-up. Challenges exist though in screening for and treating ROP, including delayed or omitted exams, lack of qualified examiners, and lack of parental adherence to instructions in following up after leaving the hospital (March of Dimes, 2019e).

Provide support to the parents. This is an extremely difficult time for them; in addition to learning to meet the needs of their preterm newborn, they must also deal with the possibility that their baby may have a condition that could lead to blindness. Consider the family’s needs and provide individualized support and guidance. Provide information about the newborn’s condition and treatment options. Stress the need for follow-up vision screenings, because ROP is considered a lifelong disease. Post-discharge follow-up of infants who are still at risk for severe ROP is paramount for timely detection and treatment.

Periventricular–Intraventricular Hemorrhage

Periventricular–intraventricular hemorrhage (PVH–IVH) in preterm infants continues to be a major clinical challenge associated with neurodevelopmental abnormalities manifested by cognitive, behavioral, attention, social, and motor deficits. PVH–IVH is defined as bleeding that usually originates in the subependymal germinal matrix region of the brain with extension into the ventricular system. The germinal matrix is the embryonic structure that is unique to preterm infants, which provides vascular supply for 24 to 32 weeks’ gestation. It is primitive and made of smooth endothelial cells which are highly vascular and prone to bleeding (de Vries & Leijser, 2020). It is a common problem in preterm infants, especially in those born before 32 weeks. It remains a significant cause of both morbidity and mortality in infants who are born prematurely. Sequelae of PVH–IVH include lifelong neurologic deficits, such as cerebral palsy, developmental delay, and seizures (Annibale, 2019).

When a fetus is born prematurely, the infant is suddenly thrust from a well-controlled uterine environment into a highly stimulating, hostile one. The tremendous physiologic stress and shock experienced by a premature infant after birth may cause the periventricular capillaries to rupture. Bleeding occurs initially in the immediate periventricular areas causing a periventricular hemorrhage (PVH). If the bleeding persists, the expanding volume of blood dissects into the adjacent lateral ventricles leading to an IVH.

A significant number of these newborns will incur brain injury, leading to complications that may include hydrocephalus, seizure disorders, periventricular leukomalacia (an ischemic injury resulting from inadequate perfusion of the white matter adjacent to the ventricles), cerebral palsy, learning disabilities, vision or hearing deficits, language difficulties, behavioral and personality disorders, and intellectual disability. Unfortunately, the different areas of the cerebral cortex are not even used by an infant for months or even years after birth, so it may take this length of time before developmental problems resulting from damage to the cerebral cortex become evident. This emphasizes the need for long-term developmental follow-up for high-risk infants. Identifying preventive strategies to reduce the incidence of these brain insults is a national public health priority (Vlasyuk, 2019).

The incidence of ventricular hemorrhage depends on the gestational age at birth. Up to 45% of newborns weighing 1,500 g or less or born at 30 weeks’ gestation or less will have evidence of hemorrhage, while only about 4% of term newborns show evidence of ventricular hemorrhage (van Bel et al., 2019). Very-low-birth-weight infants have the earliest onset of hemorrhage and the highest mortality rate. This brain injury may lead to cerebral palsy and learning difficulties, and can have a major impact on the quality of life (van Bel et al., 2019).

Pathophysiology

The pathogenesis of IVH is attributed to the intrinsic weakness of germinal vasculature and to the fluctuation in the cerebral blood flow. The fluctuation in the cerebral blood flow is attributed to the cardiorespiratory and hemodynamic instability associated with preterm infants. Hypotension, hypoxia, pneumothorax, patent ductus arteriosus, and genetics appear to also play a role in this condition (Fanaroff & Fanaroff, 2019). The preterm newborn is at greatest risk for PVH–IVH because cerebrovascular development is immature, making it more vulnerable to injury. The more premature the newborn is, the greater the likelihood for brain damage. While all areas of the brain can be injured, the periventricular area is the most vulnerable. A recent study found that an elevated midline head position of 30 degrees for the first 4 days of life decreased the likelihood of severe PVH and improved survival (Kochan et al., 2019).

Each ventricular area contains a rich network of capillaries that are very thin and fragile and can rupture easily. The causes of rupture vary and include fluctuations in systemic and cerebral blood flow, increases in cerebral blood flow from hypertension, IV infusions, seizure activity, increases in cerebral venous pressure due to vaginal delivery, hypoxia, and respiratory distress. With a preterm birth, the fetus is suddenly transported from a well-controlled uterine environment into a highly stimulating one. This tremendous physiologic stress and shock may contribute to the rupture of periventricular capillaries and subsequent hemorrhage. Most hemorrhages occur in the first 72 hours after birth (Cunningham et al., 2018).

The diagnosis of PVH–IVH is commonly made with a cranial ultrasound, a computed tomography (CT), or a magnetic resonance imaging (MRI) and then classified according to a grading system of I to V (least severe to most severe) (Starr & Borger, 2019). The prognosis is guarded, depending on the grade and severity of the hemorrhage. Generally, newborns with mild hemorrhage (grades I and II) have a much better developmental outcome than those with severe hemorrhage (grades III and IV).

Nursing Assessment

The signs of PVH–IVH vary significantly; no clinical signs may be evident. Approximately 50% of PVH–IVH occurs by 24 hours of age, and 90% occurs by 72 hours of age. Closely monitor newborns who are at an increased risk, such as those who are preterm or of low birth weight. Also assess for risk factors such as acidosis, asphyxia, unstable blood pressure, meningitis, seizures, acute blood loss, hypovolemia, respiratory distress with mechanical ventilation, intubation, apnea, hypoxia, suctioning, use of hyperosmolar solutions, rapid volume expansion, and activities that involve handling.

Evaluate the newborn for an unexplained drop in hematocrit, pallor, and poor perfusion as evidenced by respiratory distress and oxygen desaturation. Note seizures, lethargy or other changes in level of consciousness, bulging fontanelle, weak sucking, metabolic acidosis, high-pitched cry, or hypotonia/flaccidity. Palpate the anterior fontanelle for tenseness. Assess vital signs, noting bradycardia and hypotension. Evaluate laboratory data for changes indicating metabolic acidosis or glucose instability (Annibale, 2019). A bleed can often progress rapidly and result in shock and death. Prepare the newborn for cranial ultrasonography, the diagnostic tool of choice to detect hemorrhage.

Nursing Management

Prevention of preterm birth is essential in preventing PVH–IVH. Promote community awareness of factors that may contribute to PVH–IVH, such as a lack of prenatal care, maternal infection, alcohol consumption, and smoking (Kenner et al., 2019). Identify risk factors that can lead to hemorrhage and focus care on interventions to decrease the risk of hemorrhage. For example, institute measures to prevent perinatal asphyxia and birth trauma and provide developmental care in the NICU. If a preterm birth is expected, having the mother deliver at a tertiary care facility with a NICU would be preferable.