From the Journals

Lung ultrasound predicts need for first-dose surfactant in neonates

 

Key clinical point: LUS to predict the need for lung surfactant is of greatest value to preterm neonates under 34 weeks’ gestation.

Major finding: A LUS cutoff value between 6 and 8 provides optimal sensitivity and specificity for predicting the need for the first surfactant dose.

Study details: Prospective cohort diagnostic accuracy study that included 133 infants.

Disclosures: The authors had no relevant financial disclosures.

Source: De Martino L et al. Pediatrics. 2018. doi: 10.1542/peds.2018-0463.

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Point-of-care ultrasound underutilized in U.S.

Point-of-care ultrasound (POCUS) has been recognized for years for its value in assessing sick neonates, but a recent survey showed that less than one-third of U.S. neonatal-perinatal medicine programs actually use bedside ultrasound for health care diagnosis and management. Although its use historically has been confined to pediatric cardiology and radiology, it has gained more of a foothold in acute pediatric care settings, and its use in evaluating neonate lungs is a “relatively new and potentially revolutionary approach,” Maria V. Fraga, MD, and her associates wrote in an accompanying editorial.

A growing body of data over the past 2 decades is available to help radiologists and bedside providers to better understand the applications and limitations of POCUS. Findings in similar studies looking at the use of LUS in neonates “make the article by De Martino et al. so important,” Dr. Fraga and her associates emphasized. Dr. De Martino and her colleagues were able to use POCUS of the lung “to develop reliable predictive models for the need for surfactant treatment and re-dosing” in a group of preterm infants.

Although it would seem reasonable to expect the potential benefits of POCUS to have worldwide application, implementation is inconsistent. Clinicians in Australia, New Zealand, and Canada are trained and use POCUS daily, but this is not the case in other countries such as the United States. Concern over legal risks and training, as well as turf disputes with cardiology and radiology, the lack of clinicians actively using ultrasound, and scarce evidence showing benefit of its use could be to blame.

“The development of a POCUS program requires an accessible dedicated ultrasound machine kept in close proximity to clinical areas, a core group of interested clinicians, and a training and accreditation program with a commitment to continuing professional development,” advised Dr. Fraga and her associates.

“It is important to understand the limitation of bedside ultrasound, which should always be performed for a specific clinical purpose and to answer a clinical question and does not always mandate a full comprehensive study,” they added.

Dr. Fraga and her associates are affiliated with the department of pediatrics at the University of Pennsylvania, Philadelphia. There was no external funding and the authors had no relevant financial disclosures. These comments are adapted from an editorial accompanying the article by De Martino et al. (Pediatrics. 2018. doi: 10.1542/peds.2018-1621).


 

FROM PEDIATRICS

Lung ultrasound score (LUS) is an effective means of predicting whether extremely preterm neonates undergoing continuous positive airway pressure (CPAP) treatment for respiratory distress syndrome (RDS) require surfactant, according to results of study published in Pediatrics.

premature infant in incubator Herjua/Thinkstock

Lucia De Martino, MD, of the division of pediatrics and neonatal critical care at the A. Béclère Medical Centre of the South Paris University Hospital and her associates enrolled 133 neonates of 30 weeks’ gestation or less born between 2015 and 2016. They designed the prospective diagnostic accuracy cohort study, which was conducted in an academic tertiary care referral neonatal ICU.

The first dose of surfactant was administered at a mean 4 hours of life. Those that required further treatment received a second dose of surfactant at a mean 28 hours of life. Each patient received a single lung ultrasound lasting an average of 3 minutes. In each case, the procedure was well tolerated.

In particular, the study demonstrated that LUS is able to accurately predict the need for a first dose and “reveals fair accuracy when it comes to predicting surfactant retreatment,” they observed. The authors speculate that using LUS to predict retreatment is somewhat less reliable because of either the lower number of patients requiring retreatment or reasons related to the biology of surfactant.

“A LUS cutoff value between 6 and 8 provides optimal sensitivity and specificity for predicting the need for the first surfactant dose, whereas a cutoff value of 10 predicts the need for surfactant retreatment,” Dr. De Martino and her colleagues advised.

Of key importance was the finding that LUS is of greatest value to preterm infants less than 34 weeks’ gestation; the authors observed that LUS had significantly lower diagnostic accuracy in infants who were either late term or term. They offered that this outcome was likely attributable to the homogeneous nature of preterm neonates, who are commonly affected by RDS and tend to present with a variety of respiratory disorders and surfactant injury to differing degrees.

At present, international guidelines only recommend surfactant replacement in cases where CPAP has failed, but administering surfactant within the first 2-3 hours of life is key to reducing bronchopulmonary dysplasia as well as the risk of death, they said.

Current surfactant replacement is determined solely by fraction of inspired oxygen cutoff levels, which can result in delayed or even unnecessary treatment. Because neonates who are extremely preterm benefit the most from treatment, “both situations are potentially harmful because late surfactant replacement is less efficacious and giving surfactant when it is not needed may be invasive and seems to increase lung inflammation in animal models,” Dr. De Martino and her associates cautioned.

The authors had no relevant financial disclosures.

SOURCE: De Martino L et al. Pediatrics. 2018. doi: 10.1542/peds.2018-0463.

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