Approach to respiratory distress (newborn): Clinical sciences

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Introduction0:00–0:39

Newborn respiratory distress refers to an increased work of breathing beginning in the first days of life. If not recognized and treated promptly, respiratory distress can lead to respiratory failure.
Some important risk factors that can lead to respiratory distress in newborns include prematurity; conditions such as congenital diaphragmatic hernia and congenital heart disease; meconium aspiration syndrome; infections such as pneumonia and sepsis; pneumothorax; and transitory tachypnea of the newborn.When a newborn presents with respiratory distress, first perform an ABCDE assessment to determine if they are unstable or stable.

Unstable patient0:39–1:11

If unstable, stabilize their airway, breathing, and circulation. In severe cases, you might need to intubate your patient and start mechanical ventilation.
Next, obtain IV access and put your patient on continuous vital sign monitoring, including respiratory rate and pulse oximetry.
Finally, if needed, don’t forget to provide supplemental oxygen.Now, let’s return to the ABCDE assessment and take a look at stable patients.

Stable patient1:11–1:58

In this case, obtain a focused history and physical exam and check pulse oximetry. History reveals the beginning of respiratory distress in the newborn period.
The physical exam reveals signs of respiratory distress, such as grunting, nasal flaring, and suprasternal, intercostal, or subcostal retractions.
Tachypnea, or a respiratory rate above 60 per minute, will also be present. Depending on the underlying cause, you may also hear wheezing or crackles on auscultation.
Finally, pulse oximetry might show oxygen saturation below 90 percent.These findings are suggestive of respiratory distress, so your next step is to look for an underlying cause.

Respiratory distress1:58–2:26

Start by assessing prenatal ultrasound findings. If you detect an abnormal prenatal ultrasound finding that increases the risk of respiratory distress, you should consider congenital defects.
Then order a chest X-ray, as well as an echocardiogram, if needed.First, let’s start with congenital heart defects. In this case, your patient’s history usually reveals prenatal identification of a congenital heart defect, and there might even be a family history of congenital heart defects.

Congenital Heart Defect2:26–4:03

The physical examination could reveal a cyanotic newborn, with or without a heart murmur, loud S2, or hepatomegaly. Chest X-ray commonly shows cardiomegaly and increased pulmonary vascularity.
Finally, the echocardiogram will confirm the presence of structural heart abnormalities or defects with pulmonary overcirculation.
With these findings, you can confirm the diagnosis of a congenital heart defect. Now here’s a clinical pearl to keep in mind!
If an echocardiogram is not available, you could use the hyperoxia test to distinguish congenital heart conditions from lung conditions.
The test is based on the premise that supplemental oxygen will not increase the PaO2 in the presence of congenital heart disease to the same degree it would with isolated pulmonary disease.
To perform a hyperoxia test, provide the newborn with 100% oxygen for several minutes and check their oxygen saturation.
In newborns with cyanotic heart defects with an intracardiac shunt that bypasses the lungs, pulse oximetry will show little to no improvement in oxygenation.
On the other hand, when the disease is primarily a pulmonary condition, such as pneumonia or respiratory distress syndrome, the oxygen saturation will improve and rise beyond 90%.Next, up is the tracheoesophageal fistula.

Tracheoesophageal Fistula4:03–4:57

These patients might have a prenatal ultrasound finding of polyhydramnios, with features of VACTERL association, which includes Vertebral, Anal, Cardiac, Tracheo-Esophageal, Renal, or Limb abnormalities.
Physical examination usually reveals mucus and saliva bubbling from the nose and mouth. You might even notice a single artery in the umbilical cord, as well as various findings consistent with VACTERL, such as anal atresia or absent thumbs.
Before you order a chest X-ray, place an orogastric tube. In these patients, the radiograph will likely demonstrate a coiled tube within the esophagus, suggesting the presence of a tracheoesophageal fistula with esophageal atresia.
Finally, let’s go over the congenital diaphragmatic hernia, or CDH for short. In this case, prenatal ultrasound will mention a congenital diaphragmatic hernia.

Congenital Diaphragmatic Hernia4:57–6:17

The physical exam will reveal a scaphoid abdomen and the presence of bowel sounds in the chest. These findings are indicative of congenital diaphragmatic hernia, but if the diagnosis is still unclear, order a chest X-ray.
X-ray findings suggestive of CDH include bowel loops and gas visible in the left hemithorax, with displacement of the cardiac silhouette to the right.
Keep in mind that CDH most often occurs on the left side since the liver usually blocks the intestines from migrating into the chest cavity.
At this point, you can confirm the diagnosis of a congenital diaphragmatic hernia.Now here’s a clinical pearl to keep in mind!
Some craniofacial malformations can cause upper airway obstruction shortly after birth. One example is bilateral choanal atresia, which blocks the posterior nares.
Since neonates are obligate nose breathers, when feeding, they experience respiratory distress. While crying, however, respiratory distress is relieved when they breathe with an open mouth.Now, let’s switch gears and discuss newborns with normal prenatal ultrasound findings.

Meconium Aspiration Syndrome6:17–7:16

In this case assess perinatal risk factors. First, let’s focus on meconium-stained amniotic fluid.
In this case, you should consider meconium aspiration syndrome as a cause of respiratory distress, so make sure to order a chest X-ray!
Affected infants are typically born at term or post-term, and intrapartum fetal distress may have been noted. The physical exam will likely demonstrate a barrel-shaped chest with increased work of breathing, nasal flaring, grunting, or retractions, as well as diffuse crackles, rhonchi, or wheezing.
If the chest X-ray reveals bilateral fluffy densities and lung hyperinflation, you can diagnose meconium aspiration syndrome.

Respiratory Distress Syndrome7:16–8:23

Alright, next, let’s consider the next risk factor of prematurity. Prematurity should prompt you to consider complications, such as respiratory distress syndrome and patent ductus arteriosus.
In this case, order a chest X-ray or lung ultrasound. With respiratory distress syndrome, your physical exam will reveal poor air movement, tachypnea, and retractions; and crackles might be heard upon auscultation.
If the X-ray reveals a ground glass appearance with air bronchograms and hypoexpansion, or if the ultrasound shows compact B lines with an echographic white lung appearance, diagnose respiratory distress syndrome.
Here's a high-yield fact to keep in mind! Respiratory distress syndrome typically occurs in preterm infants due to underdeveloped lungs and surfactant deficiency!
But, term infants who are born to diabetic mothers also have an increased risk of respiratory distress syndrome, since fetal hyperglycemia and hyperinsulinemia can disrupt surfactant synthesis!

Patent Ductus Arteriosus8:23–8:54

Another important cause of respiratory distress in premature infants is patent ductus arteriosus or PDA for short. In these babies, more blood is traveling to the lungs, increasing pressure in the pulmonary circulation and causing respiratory distress.
The physical exam reveals a continuous, machinery-like murmur that radiates to the infant’s back, and bounding peripheral pulses.
If the chest X-ray shows increased pulmonary vascularity, diagnose PDA.Now let’s move on and discuss risk factors for infection.

Infection8:54–9:34

This includes maternal fever or chorioamnionitis; positive GBS with inadequate intrapartum antibiotic prophylaxis; or prolonged rupture of membranes.
The presence of any of these should make you consider the possibility of infection. In this case, order labs, including a procalcitonin or C-reactive protein, and obtain blood cultures.
Additionally, depending on your patient’s clinical picture, you might need to obtain urine and CSF cultures. Again, don’t forget to order a chest X-ray.
Let’s start with sepsis. Sepsis is typically associated with temperature instability, tachypnea, and normal lung findings.

Neonatal Sepsis9:34–9:52

The chest X-ray will be normal, but the blood culture will be positive. All of these findings are suggestive of sepsis!On the flip side, infants with pneumonia will usually have focal lung findings, such as rhonchi and crackles, in addition to temperature instability.

Neonatal Pneumonia9:52–10:12

In contrast to sepsis, the chest X-ray will show diffuse parenchymal infiltrates, air bronchograms, or lobar consolidation.
These findings are highly suggestive of pneumonia. Next, let’s discuss patients with respiratory distress who have been receiving mechanical ventilation.

Pneumothorax10:12–11:06

For these patients, be sure to consider the possibility of pneumothorax, and order a chest X-ray or lung ultrasound. The physical exam will reveal decreased breath sounds on the affected side, while chest X-ray findings include a shadow of visceral pleura with absent lung markings.
Additionally, lung ultrasound findings include the absence of lung sliding and B lines, with the presence of a lung point.
With these findings, you can confirm the diagnosis of pneumothorax. Now here’s a clinical pearl to keep in mind!
If your patient develops hypotension, tachycardia, and tracheal deviation, you should immediately suspect tension pneumothorax, and perform an emergency thoracostomy and tube placement!Now let’s switch our focus to risk factors for delayed transition of newborn.

Delayed transition of the newborn11:06–11:42

This includes infants born by cesarean delivery, who had a precipitous delivery, or whose mothers have diabetes; as well as newborns without any identifiable risk factors.
In this case, you should monitor your patient and assess for resolution of symptoms by 6 hours of age. If symptoms resolve within 6 hours, diagnose delayed transition of the newborn.On the other hand, if your patient has persistent respiratory distress, consider ordering imaging studies such as a chest X-ray or lung ultrasound.

Transient Tachypnea of the Newborn11:42–12:54

Infants with transient tachypnea of the newborn typically have respiratory distress that lasts beyond 6 hours of life. Physical exam findings are significant for grunting, nasal flaring, retractions, and tachypnea, often with a respiratory rate over 80 breaths per minute.
Typical chest X-ray findings are similar to pulmonary edema, with diffuse increased interstitial lung markings where fluid may be seen in an interlobar fissure.
include the presence of fluid in the interlobar fissure, with perihilar streaking, while a lung ultrasound will demonstrate double lung points.
With these findings, you can diagnose transient tachypnea of the newborn. And here’s one final clinical pearl to keep in mind!
If the newborn experiences persistent respiratory distress despite adequate treatment for pulmonary conditions, like meconium aspiration syndrome or respiratory distress syndrome, you should suspect persistent pulmonary hypertension of the newborn, or, PPHN.
In this case, order an echocardiogram, and if it reveals elevated pulmonary artery pressures with right-to-left shunting, you can diagnose PPHN.Alright, as a quick recap… When a newborn presents with respiratory distress, first perform an ABCDE assessment.

Review12:54–13:56

If they are unstable, stabilize their airway, breathing, and circulation. If needed, intubate and start mechanical ventilation.
For stable patients, review prenatal ultrasound findings to help you identify causes of respiratory distress, such as congenital heart defects, tracheoesophageal fistula, and congenital diaphragmatic hernia.
If prenatal ultrasound findings were normal, check perinatal risk factors, which can give clues to the underlying cause.The most important acquired causes of respiratory distress include meconium aspiration syndrome, respiratory distress syndrome, patent ductus arteriosus, infections, and pneumothorax.
Finally, don't forget that, in some infants,
Approach to respiratory distress (newborn): Video | Osmosis