Successful use of surfactant to treat severe intrapulmonary hemorrhage after iatrogenic lung injury--A case report

Neonatal surfactant therapy beyond respiratory distress syndrome

Whilst exogenous surfactant therapy is central to the management of newborn infants with respiratory distress syndrome, its use in other neonatal lung diseases remains inconsistent and controversial. Here we discuss the evidence and experience in relation to surfactant therapy in newborns with other lung conditions in which surfactant may be deficient or dysfunctional, including meconium aspiration syndrome, pneumonia, congenital diaphragmatic hernia and pulmonary haemorrhage. We find that, for all of these diseases, administration of exogenous surfactant as bolus therapy is frequently associated with transient improvement in oxygenation, likely related to temporary mitigation of surfactant inhibition in the airspaces. However, for none of them is there a lasting clinical benefit of surfactant therapy. By virtue of interrupting disease pathogenesis, lavage therapy with dilute surfactant in MAS offers the greatest possibility of a more pronounced therapeutic effect, but this has yet to be definitively proven. Lavage therapy also involves a greater degree of procedural risk.

Early therapy with corticosteroid and surfactant for acute idiopathic pulmonary hemorrhage in infants: Two case reports

RATIONALE

Acute idiopathic pulmonary hemorrhage (AIPH) in infants is a rare condition, and a clear treatment protocol has not yet been established.

PATIENT CONCERNS

We report 2 infant cases of AIPH in a 3-month-old male and a 1-month-old female, who presented at an emergency room with epistaxis and respiratory distress. Both were immediately intubated, which revealed a bloody intratracheal aspirate.

DIAGNOSIS

Pulmonary hemorrhage was confirmed by X-ray and computed tomography imaging in both cases. The extensive evaluation revealed no specific etiology for the acute pulmonary hemorrhage, and AIPH was therefore diagnosed in both cases.

INTERVENTIONS

Intravenous methylprednisolone resulted in a rapid improvement in oxygenation and a reduction in high airway pressure during mechanical ventilation. Methylprednisolone was subsequently tapered off within 13 and 3 days in cases 1 and 2, respectively. In case 1, intratracheal administration of a surfactant also resulted in an immediate improvement in respiratory condition and the patient was extubated after 2 days; no effect was seen in case 2, and the patient was extubated after 10 days.

OUTCOME

Both infants recovered well without sequelae or further relapse after 23 and 71 months of follow-up, respectively.

LESSONS

Early administration of corticosteroid therapy and intratracheal administration of diluted surfactant should be considered for severe acute pulmonary hemorrhage in infants.

Surfactant for pulmonary haemorrhage in neonates

BACKGROUND

In the 1960s and 1970s, pulmonary haemorrhage (PH) occurred mainly in full-term infants with pre-existing illness with an incidence of 1.3 per 1000 live births. Risk factors for PH included severity of illness, intrauterine growth restriction, patent ductus arteriosus (PDA), coagulopathy and the need for assisted ventilation. Presently, PH occurs in 3% to 5% of preterm ventilated infants with severe respiratory distress syndrome (RDS) who often have a PDA and have received surfactant. The cause of PH is thought to be due to rapid lowering of intrapulmonary pressure, which facilitates left to right shunting across a PDA and an increase in pulmonary blood flow. Retrospective case reports and one prospective uncontrolled study have shown promising results for surfactant in treating PH.

OBJECTIVES

To evaluate the effect of surfactant treatment compared to placebo or no intervention on mortality and morbidities in neonates with PH.

SEARCH METHODS

For this update The Cochrane Library, Issue 2, 2012; MEDLINE; EMBASE; CINAHL; Clinicaltrials.gov; Controlled-trials.com; proceedings (2000 to 2011) of the Annual Meetings of the Pediatric Academic Societies (Abstracts2View) and Web of Science were searched on 8 February 2012.

SELECTION CRITERIA

Randomised or quasi-randomised controlled trials that evaluated the effect of surfactant in the treatment of PH in intubated term or preterm (< 37 weeks) neonates with PH. Infants were included up to 44 weeks' postmenstrual age. The interventions studied were intratracheal instillation of surfactant (natural or synthetic, regardless of dose) versus placebo or no intervention.

DATA COLLECTION AND ANALYSIS

If studies were identified by the literature search, the planned analyses included risk ratio, risk difference, number needed to treat to benefit or to harm for dichotomous outcomes, and mean difference for continuous outcomes, with their 95% confidence intervals. A fixed-effect model would be used for meta-analyses. The risk of bias for included trials would be assessed. Heterogeneity tests, including the I2 statistic, would be performed to assess the appropriateness of pooling the data and the results would be reported.

MAIN RESULTS

No trials were identified.

AUTHORS' CONCLUSIONS

No randomised or quasi-randomised trials that evaluated the effect of surfactant in PH were identified. Therefore, no conclusions from such trials can be drawn. In view of the promising results from studies with less strict study designs than a randomised controlled trial, there is reason to conduct further trials of surfactant for the treatment of PH in neonates.

Surfactant Replacement Therapy Beyond Respiratory Distress Syndrome in Neonates

BACKGROUND

Surfactant replacement therapy is an established modality of treatment in preterm neonates with respiratory distress syndrome. In addition, there are various neonatal respiratory disorders which are characterized by surfactant deficiency in which surfactant therapy can be a feasible and safe option.

OBJECTIVE

To collate the literature on the use of surfactant replacement therapy in neonates beyond respiratory distress syndrome and examine the evidence and newer developments.

SEARCH METHODS

We searched the Cochrane Central Register of Controlled Trials (CENTRAL, The Cochrane Library), MEDLINE, and EMBASE up to June 2015; and previous reviews, including cross-references, abstracts, and conference proceedings.

RESULTS

Evidence supports surfactant administration via bolus route in neonates with meconium aspiration syndrome, but additional robust evidence is required before its adoption in clinical practice. There is limited evidence to support surfactant therapy in neonates with pneumonia, pulmonary hemorrhage and bronchopulmonary dysplasia. Large multicenter randomized trials are needed to cement or refute the role of surfactant therapy in these disorders.

Exogenous surfactant therapy in 2013: what is next? Who, when and how should we treat newborn infants in the future?

Background

Surfactant therapy is one of the few treatments that have dramatically changed clinical practice in neonatology. In addition to respiratory distress syndrome (RDS), surfactant deficiency is observed in many other clinical situations in term and preterm infants, raising several questions regarding the use of surfactant therapy.

Objectives

This review focuses on several points of interest, including some controversial or confusing topics being faced by clinicians together with emerging or innovative concepts and techniques, according to the state of the art and the published literature as of 2013. Surfactant therapy has primarily focused on RDS in the preterm newborn. However, whether this treatment would be of benefit to a more heterogeneous population of infants with lung diseases other than RDS needs to be determined. Early trials have highlighted the benefits of prophylactic surfactant administration to newborns judged to be at risk of developing RDS. In preterm newborns that have undergone prenatal lung maturation with steroids and early treatment with continuous positive airway pressure (CPAP), the criteria for surfactant administration, including the optimal time and the severity of RDS, are still under discussion. Tracheal intubation is no longer systematically done for surfactant administration to newborns. Alternative modes of surfactant administration, including minimally-invasive and aerosolized delivery, could thus allow this treatment to be used in cases of RDS in unstable preterm newborns, in whom the tracheal intubation procedure still poses an ethical and medical challenge.

Conclusion

The optimization of the uses and methods of surfactant administration will be one of the most important challenges in neonatal intensive care in the years to come.

Surfactant for pulmonary haemorrhage in neonates

BACKGROUND

In the 1960s and 1970s, pulmonary haemorrhage (PH) occurred mainly in full-term infants with pre-existing illness with an incidence of 1.3 per 1000 live births. Risk factors for PH included severity of illness, intrauterine growth restriction, patent ductus arteriosus (PDA), coagulopathy and the need for assisted ventilation. Presently, PH occurs in 3% to 5% of preterm ventilated infants with severe respiratory distress syndrome (RDS) who often have a PDA and have received surfactant. The cause of PH is thought to be due to rapid lowering of intrapulmonary pressure, which facilitates left to right shunting across a PDA and an increase in pulmonary blood flow. Retrospective case reports and one prospective uncontrolled study have shown promising results for surfactant in treating PH.

OBJECTIVES

To evaluate the effect of surfactant treatment compared to placebo or no intervention on mortality and morbidities in neonates with PH.

SEARCH METHODS

For this update The Cochrane Library, Issue 2, 2012; MEDLINE; EMBASE; CINAHL; Clinicaltrials.gov; Controlled-trials.com; proceedings (2000 to 2011) of the Annual Meetings of the Pediatric Academic Societies (Abstracts2View) and Web of Science were searched on 8 February 2012.

SELECTION CRITERIA

Randomised or quasi-randomised controlled trials that evaluated the effect of surfactant in the treatment of PH in intubated term or preterm (< 37 weeks) neonates with PH. Infants were included up to 44 weeks' postmenstrual age. The interventions studied were intratracheal instillation of surfactant (natural or synthetic, regardless of dose) versus placebo or no intervention.

DATA COLLECTION AND ANALYSIS

If studies were identified by the literature search, the planned analyses included risk ratio, risk difference, number needed to treat to benefit or to harm for dichotomous outcomes, and mean difference for continuous outcomes, with their 95% confidence intervals. A fixed-effect model would be used for meta-analyses. The risk of bias for included trials would be assessed. Heterogeneity tests, including the I(2) statistic, would be performed to assess the appropriateness of pooling the data and the results would be reported.

MAIN RESULTS

No trials were identified.

AUTHORS' CONCLUSIONS

No randomised or quasi-randomised trials that evaluated the effect of surfactant in PH were identified. Therefore, no conclusions from such trials can be drawn. In view of the promising results from studies with less strict study designs than a randomised controlled trial, there is reason to conduct further trials of surfactant for the treatment of PH in neonates.

Surfactant for pulmonary hemorrhage in neonates

BACKGROUND

In the late 1960's and 1970's, pulmonary hemorrhage (PH) occurred mainly in full term infants with severe pre-existing illness. The incidence of PH was quoted as 1.3 per 1,000 live births. In the older medical literature, the risk factors associated with PH included the severity of the associated illness, intrauterine growth restriction, patent ductus arteriosus (PDA), coagulopathy, and the need for assisted ventilation. Presently, PH occurs mainly in preterm ventilated infants with severe respiratory distress syndrome (RDS) who often have a PDA and have received surfactant. Currently, PH complicates the hospital course of 3-5% of preterm infants with RDS. Although not clear, the cause of PH is thought to be due to a rapid lowering of intrapulmonary pressure, which facilitates left to right shunting across a patent ductus arteriosus and an increase in pulmonary blood flow. Retrospective case reports and one prospective uncontrolled study that used surfactant for PH in neonates have shown promising results in treating PH.

OBJECTIVES

To evaluate the effect of surfactant treatment compared to placebo or no intervention on mortality in neonates with pulmonary hemorrhage. In addition, the review will evaluate the effect of surfactant treatment on neonatal morbidities associated with PH compared to placebo or no intervention.

SEARCH STRATEGY

The following databases were searched in January 2008: The Cochrane Central Register of Controlled Trials (CENTRAL, The Cochrane Library, Issue 4, 2007) and MEDLINE from 1966 and EMBASE from 1980 to the time of the full review using the OVID interface. The proceedings of the Annual Meetings of the Pediatric Academic Societies and the European Society of Pediatric Research published in Pediatric Research or electronically on their web sites were searched from 1994 to the time of the full review. Science citation index (Web of Science) was searched for authors quoting key references of observational studies.

SELECTION CRITERIA

Randomised or quasi-randomised controlled trials that evaluated the effect of surfactant in the treatment of PH in intubated term or preterm (< 37 weeks) neonates with PH. Infants were included up to 44 weeks postmenstrual age. Infants were included regardless of prior treatment with surfactant. The interventions studied were intratracheal instillation of surfactant (natural or synthetic, regardless of dose) vs. placebo or no intervention.

DATA COLLECTION AND ANALYSIS

If studies were identified by the literature search, the planned analyses included calculation of the relative risk (RR), risk difference (RD), number needed to treat (NNT) or number needed to harm (NNH) for dichotomous outcomes, and weighed mean difference (WMD) for continuous outcomes, with their 95% confidence intervals (CI). A fixed effects model would be used for meta-analyses. Heterogeneity tests, including the I- squared (I(2)) statistic, would be performed to assess the appropriateness of pooling the data and the results would be reported.

MAIN RESULTS

No trials were identified.

AUTHORS' CONCLUSIONS

No randomized or quasi-randomized trials that evaluated the effect of surfactant in PH were identified. Therefore, no conclusions from such trials can be drawn. In view of the promising results from studies with less strict study designs than a randomized controlled trial, there is reason to conduct further trials of surfactant for the treatment of PH in neonates.

What's new in surfactant? A clinical view on recent developments in neonatology and paediatrics

Surfactant therapy has significantly changed clinical practice in neonatology over the last 25 years. Recent trials in infants with respiratory distress syndrome (RDS) have not shown superiority of any natural surfactant over another. Advancements in the development of synthetic surfactants are promising, yet to date none has been shown to be superior to natural preparations. Ideally, surfactant would be administered without requiring mechanical ventilation. An increasing number of studies investigate the roles of alternative modes of administration and the use of nasal continuous positive airway pressure to minimise the need for mechanical ventilation. Whether children with other lung diseases benefit from surfactant therapy is less clear. Evidence suggests that infants with meconium aspiration syndrome and children with acute lung injury/acute respiratory distress syndrome may benefit, while no positive effect of surfactant is seen in infants with congenital diaphragmatic hernia. However, more research is needed to establish potential beneficial effects of surfactant administration in children with lung diseases other than RDS. Furthermore, genetic disorders of surfactant metabolism have recently been linked to respiratory diseases of formerly unknown origin. It is important to consider these disorders in the differential diagnosis of unexplained respiratory distress although no established treatment is yet available besides lung transplantation for the most severe cases.

CONCLUSION

Research around surfactant is evolving and recent developments include further evolution of synthetic surfactants, evaluation of surfactant as a therapeutic option in lung diseases other than RDS and the discovery of genetic disorders of surfactant metabolism. Ongoing research is essential to continue to improve therapeutic prospects for children with serious respiratory disease involving disturbances in surfactant.