The Use of Lung Ultrasonography in the Delivery Room in Neonates

Lung ultrasonography (LUS) was first used in adults in 1995 and has been used in neonatology and pediatrics in recent years and has become increasingly widespread. Lung ultrasonography has become frequently used in neonatal intensive care units because it is a diagnostic, useful, harmless, radiation-free, bedside, reproducible and practical method. (1, 2) In our clinic, lung ultrasonography imaging is performed in infants hospitalized with respiratory distress.

Lung ultrasonography is widely used especially in conditions that mainly cause respiratory distress such as respiratory distress syndrome (RDS), pneumonia, neonatal transient tachypnea (NTRT), congenital pneumonia, meconium aspiration syndrome and pneumothorax. (1, 2) The reliability and specificity of AUS imaging especially in the diagnosis of RDS have been proven in many studies. (1,2,3) The diagnosis of RDS on lung ultrasonography is made by "visualization of the transition zone (double lung point)" (3). In addition, "white lung appearance" in RDS, "absence of pleural motion and "barcode" appearance in M mode" in the presence of pneumothorax, one of the air leakage syndromes, and "hepatization/consolidation appearance" in pneumonia are among ultrasonographic findings (1,3).

In infants whose lung ultrasound findings are compatible with RDS and who clinically require surfactant, surfactant therapy is given in a shorter time without waiting for chest radiography. In a study involving 40 patients diagnosed with RDS, it was found that there was a significant improvement ultrasonographically in the 4th hour of surfactant treatment, and in another study, it was shown that chest radiography was dramatically reduced with the use of AUS. (4, 5) In the light of this information, we see that the use of AUS is becoming increasingly widespread in newborns. AUS imaging has now become an objective value by scoring. With these scores, the relationship between the diagnosis of the disease and the score has been tried to be determined and related studies have been conducted. (6,7) Images will be obtained using the linear probe of the device to be used for lung ultrasound and transferred to a cell phone. The AUS scoring described in the studies of Brat et al. and Raimondi et al. (8,9) Accordingly, both lungs will be evaluated as three areas on the right and left (anterior superior, anterior inferior and lateral) and scored separately. Anteriorly, the region between the anterior axillary line and the parasternal line is divided into two by the line passing through the nipple. Above is considered as the upper anterior region and below as the lower anterior region. The area in the middle of the anterior and posterior axillary line is evaluated as the lateral region. Each area is scored from 0 to 3 points. If A lines are present, 0 points are given, if there are more than 3 B lines in an area, 1 point is given, if B lines are very dense and there are no A lines, it is considered as white lung and 2 points are given. If there is a consolidation image on AUS, 3 points were given. The maximum total score was 18 (8,9) (Figure 1).

The transition from fetal to extrauterine life requires numerous rapid organ adaptations. Clearance of fetal lung fluid, surfactant secretion and the onset of steady breathing occur during pulmonary adaptation, and changes in blood flow, increased cardiac output and pulmonary vasodilation occur for the cardiovascular transition. (10) This period typically lasts for two hours. During this period, placental breathing is replaced by spontaneous breathing. When there is a delay in transition during this adaptation process, tachypnea and moaning may be observed. This process should be distinguished from transient tachypnea (wet lung) of the newborn. In case of respiratory distress that persists after the first two hours postnatally, the transition delay is avoided (10). Transient tachypnea of the newborn is considered as a possible diagnosis. If there is a risk factor or respiratory distress persists and laboratory and imaging methods support it, congenital pneumonia at 34 weeks and above is frequently included among the diagnoses presenting with respiratory distress. In addition, RDS can also be seen rarely in this period (3).

When we perform AUS imaging in the delivery room, i.e. within the first 30 minutes, we may see pulmonary edema, diffuse B lines, or a normal lung that has completed its transition and has more A lines. Newborns who do not require neonatal hospitalization due to respiratory distress will also be followed up in the maternal ward and their clinic will be evaluated according to the AUS score they received in the delivery room.

In the study, both AUS imaging and scoring will be performed in the delivery room within the first 30 minutes and AUS score evaluation will be performed in the intensive care unit for inpatients and in the maternity ward for maternal patients at postnatal 2nd, 6th and 24th hours. The hypothesis of this study is that newborns with high AUS scores will have high rates of respiratory morbidities and respiratory support in the neonatal unit. The primary aim of the study was to determine the role and importance of AUS scores measured in the delivery room in predicting respiratory morbidities of infants. The secondary aim was to investigate the value of the course of AUS scores at postnatal 2, 6 and 24 hours in predicting the respiratory prognosis of the newborn infant.

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