The team must be aware of conditions that can develop after resuscitation:

Pneumonia

Neonates with pneumonia, perinatal infections, or meconium aspiration will show signs of respiratory distress, such as tachypnea, retractions, nasal flaring, and grunting. The mother’s perinatal history provides insights into any risk factors for pneumonia.

Other common respiratory problems among babies in the NICU include respiratory distress syndrome (RDS) and retained fetal lung fluid. Chest X-ray findings are similar for pneumonia, retained fetal lung fluid, and RDS.

Pneumothorax

Pneumothorax can occur during resuscitation secondary to volutrauma if too much pressure is applied while giving ventilation. Pneumothorax can present as the sudden deterioration of a recovering baby during or after resuscitation. A pneumothorax is readily diagnosed with a chest X-ray.

Displacement of the endotracheal tube during ventilatory support can also contribute to pneumothorax.

Related Video: Hs and Ts: Tension Pneumothorax

Infant with right-sided pneumothorax

Pulmonary Hypertension

Pulmonary hypertension occurs when the pulmonary vasculature fails to dilate during the transition to extrauterine life. Persistent pulmonary hypertension of the newborn (PPHN) is a condition most often observed in babies who are ≥ 34 weeks gestation.  

Management of PPHN includes respiratory support with oxygen and mechanical ventilation. In severe cases, the patient may need inhaled nitric oxide (a potent vasodilator) or extracorporeal membrane oxygenation (ECMO).

The pulmonary vascular tone in newborns who have undergone neonatal resuscitation may be extremely sensitive to hypothermia or sudden changes in oxygen saturation. However, maintaining high concentrations of arterial oxygen may cause complications later. SpO₂ monitoring and arterial blood gases are equally necessary for informing the attending physician on the appropriate supplemental oxygen concentration level for the neonate.

Hypotension

After successful neonatal resuscitation, patients are prone to hypotension. Low oxygen levels affect cardiac function and vascular tone. If the baby has had blood loss, the resultant hypovolemia can be a cause of hypotension. Sepsis dilates the peripheral blood vessels and contributes to hypotension. 

Blood pressure monitoring is essential until it is certain that the newborn can maintain normotension. Volume expanders are indicated for patients with hypotension secondary to hypovolemia. Volume can be administered via intravenous infusions of crystalloid solution. If severe anemia is present, blood transfusions may be necessary. Sympathomimetic drugs such as dopamine and dobutamine help increase blood pressure and improve cardiac function.

Neonatal blood pressure cuff and machine.

Neonatal blood pressure cuff placed on the leg.

Hypoglycemia

Hypoglycemia occurs in the face of anaerobic metabolism caused by inadequate ventilation and perinatal stress. Blood glucose levels initially increase in stressed newborns and then fall. The body utilizes glucose quickly during anaerobic metabolism, and the depletion of glucose quickly results in hypoglycemia.

Since glucose is a major fuel for brain function, persistent hypoglycemia can cause brain injury. After neonatal resuscitation, the baby’s blood glucose should be checked. If hypoglycemia is present, IV dextrose is indicated to support normal blood glucose while the newborn is unable to feed.

Feeding Problem

Feeding intolerance, uncoordinated gastrointestinal (GI) motility, inflammation, bleeding, and perforation result from poor perfusion to the GI tract. If neurologic function is also affected, the newborn may have uncoordinated sucking and feeding patterns. Therefore, it may be necessary to provide parenteral nutrition or other alternative feeding methods to the newborn who has undergone resuscitation.

Breastmilk is the best source of nutrition for the newborn. If the baby is unable to feed, mothers should start milk production in anticipation of feeding their child. The mother should receive support from a lactation expert, receive assistance in using a breast pump, and be provided with a method to store her breast milk.

Renal Failure

Inadequate perfusion of the kidneys during cardiac arrest can cause acute tubular necrosis (ATN). ATN results in fluid retention and electrolyte imbalances. Low urine output is a significant clinical finding. Impaired renal function may leave excessive volume in the circulation.

To prevent volume dilution, hypertension, the harmful effects of edema, and further damage to the kidneys, the neonate undergoes fluid restriction for several days. An increase in urine output is a positive sign that the newborn is recovering from ATN.

Neonates who have undergone resuscitation should have monitoring of their urine output, serum electrolyte levels, and body weight. If the neonate exhibits increased urine output, IV fluid supplementation and electrolyte supplementation might be necessary.

Metabolic Acidosis

Anaerobic metabolism during cardiac arrest may precipitate metabolic acidosis secondary to acid production by the tissues in the face of insufficient oxygenation and tissue perfusion. Metabolic acidosis degrades cardiac function and causes the pulmonary vasculature to constrict.

When cardiac and respiratory function return to normal, metabolic acidosis resolves. Thus, the goal of the attending physician is to diagnose and treat the cause of metabolic acidosis.

Related Video – Understanding and Interpreting ABGs Part 7: Metabolic Acidosis

Hypoxemic Ischemic Encephalopathy

Hypoxemic ischemic encephalopathy (HIE) results from poor brain perfusion secondary to hypotension, hypoxemia, and metabolic acidosis. Newborns in need of resuscitation are prone to HIE. Infants with HIE present with poor muscle tone, lethargy, apnea, poor respiratory function, and seizures. Therefore, patients who have undergone neonatal resuscitation must undergo neurologic examinations and neurologic function monitoring using a standardized assessment tool. 

Consultation with a pediatric neurologist is recommended in the postresuscitation period. Therapeutic hypothermia should be considered for infants born at > 36 weeks gestation with worsening HIE. Studies show that these newborns may benefit from therapeutic hypothermia.¹²

Fetal exposure to maternal narcotic use, anesthetics, perinatal infections, perinatal electrolyte imbalances, and perinatal metabolic abnormalities also contribute to neurologic complications during the postnatal period.

Hypothermia and Hyperthermia

Preterm newborns are prone to hypothermia and at risk for increased mortality. These patients need specific interventions to avoid and resolve hypothermia. 

On the other hand, newborns with hyperthermia may have contracted an illness from mothers with fever or from chorioamnionitis during prolonged labor. Babies may also develop hyperthermia if the radiant warmer is set at too high a temperature. Babies with HIE and hyperthermia are at risk of poor outcomes.