Ibuprofen for the prevention of patent ductus arteriosus in preterm and/or low birth weight infants

Survey of PDA management in very low birth weight infants across Italy

Background

The optimal management of PDA in very low birth weight (VLBW) infants is still controversial. Aim of our study was to investigate the management of PDA in the Italian neonatal intensive care units (NICU).

Methods

We conducted an on-line survey study from June to September 2017. A 50-items questionnaire was developed by the Italian Neonatal Cardiology Study Group and was sent to Italian NICUs.

Results

The overall response rate was 72%. Diagnosis of PDA was done by neonatologists, cardiologists or both (62, 12 and 28% respectively). PDA significance was assessed by a comprehensive approach in all centers, although we found a heterogeneous combination of parameters and cut-offs used. None used prophylactic treatment. 19% of centers treated PDA in the first 24 h, 60% after the first 24 h, following screening echocardiography or clinical symptoms, 18% after the first 72 h and 2% after the first week. In the first course of treatment ibuprofen, indomethacin and paracetamol were used in 87, 6 and 7% of centers respectively. Median of surgical ligation was 3% (1–6%).

Conclusions

Significant variations exist in the management of PDA in Italy. Conservative strategy and targeted treatment to infants older than 24 h with echocardiographic signs of hemodynamic significance seemed to be the most adopted approach.

Ibuprofen for the prevention of patent ductus arteriosus in preterm and/or low birth weight infants

BACKGROUND

Patent ductus arteriosus (PDA) complicates the clinical course of preterm infants and increases the risk of adverse outcomes. Indomethacin has been the standard treatment to close a PDA but is associated with renal, gastrointestinal, and cerebral side effects. Ibuprofen has less effect on blood flow velocity to important organs.

OBJECTIVES

Primary objectives To determine the effectiveness and safety of ibuprofen compared to placebo/no intervention, or other cyclo-oxygenase inhibitor drugs in the prevention of PDA in preterm infants.

SEARCH METHODS

We used the standard search strategy of Cochrane Neonatal to search the Cochrane Central Register of Controlled Trials (CENTRAL; 2018, Issue 10), MEDLINE via PubMed (1966 to 17 October 2018), Embase (1980 to 17 October 2018), and CINAHL; 1982 to 17 October 2018). We searched clinical trials databases, conference proceedings, and the reference lists of retrieved articles for randomised controlled trials and quasi-randomised trials.

SELECTION CRITERIA

Randomised and quasi-randomised controlled trials comparing ibuprofen with placebo/no intervention or other cyclo-oxygenase inhibitor drugs to prevent PDA in preterm or low birth weight infants.

DATA COLLECTION AND ANALYSIS

We extracted outcomes data including presence of PDA on day three or four of life (after 72 hours of treatment), need for surgical ligation or rescue treatment with cyclo-oxygenase inhibitors, mortality, cerebral, renal, pulmonary, and gastrointestinal complications. We performed meta-analyses and reported treatment estimates as typical mean difference (MD), risk ratio (RR), risk difference (RD) and, if statistically significant, number needed to treat to benefit (NNTB) or to harm (NNTH), along with their 95% confidence intervals (CI). We assessed between-study heterogeneity by the I-squared test (I²). We used the GRADE approach to assess the quality of evidence.

MAIN RESULTS

In this updated analysis, we included nine trials (N = 1070 infants) comparing prophylactic ibuprofen (IV or oral) with placebo/no intervention or indomethacin. Ibuprofen (IV or oral) probably decreases the risk of PDA on day 3 or 4 (typical RR 0.39, 95% CI 0.31 to 0.48; typical RD -0.26, 95% CI -0.31 to -0.21; NNTB 4, 95% CI 3 to 5; 9 trials; N = 1029) (moderate-quality evidence). In the control group, the spontaneous closure rate was 58% by day 3 to 4 of age. In addition, ibuprofen probably decreases the need for rescue treatment with cyclo-oxygenase inhibitors (typical RR 0.17, 95% CI 0.11 to 0.26; typical RD -0.27, 95% CI -0.32 to -0.22; NNTB 4; 95% CI 3 to 5),and the need for surgical ductal ligation (typical RR 0.46, 95% CI 0.22 to 0.96; typical RD -0.03, 95% CI -0.05 to -0.00; NNTB 33, 95% CI 20 to infinity; 7 trials; N = 925) (moderate-quality evidence). There was a possible decrease in the risk of grade 3 or 4 intraventricular haemorrhage (IVH) in infants receiving prophylactic ibuprofen (typical RR 0.67, 95% CI 0.45 to 1.00; I² = 34%; typical RD -0.04, 95% CI -0.08 to- 0.00; I² = 60%; 7 trials; N = 925) (moderate-quality evidence). High quality evidence showed increased risk for oliguria (typical RR 1.45, 95% CI 1.04 to 2.02; typical RD 0.06, 95% CI 0.01 to 0.11; NNTH 17, 95% CI 9 to 100; 4 trials; N = 747). Low quality results from four studies (N = 202) showed that administering oral ibuprofen may decrease the risk of PDA (typical RR 0.47, 95% CI 0.30 to 0.74) and may increase risk of gastrointestinal bleeding (NNTH 7, 95% CI 4 to 25). No evidence of a difference was identified for mortality, any intraventricular haemorrhage (IVH), or chronic lung disease.

AUTHORS' CONCLUSIONS

This review shows that prophylactic use of ibuprofen, compared to placebo or no intervention, probably decreases the incidence of patent ductus arteriosus, the need for rescue treatment with cyclo-oxygenase inhibitors, and for surgical ductal closure. Adverse effects associated with ibuprofen (IV or oral) included increased risks for oliguria, increase in serum creatinine levels, and increased risk of gastrointestinal haemorrhage. There was a reduced risk for intraventricular haemorrhage (grade III - IV) but no evidence of a difference in mortality, chronic lung disease, necrotising enterocolitis, or time to reach full feeds. In the control group, the patent ductus arteriosus had closed spontaneously by day 3 or 4 in 58% of neonates. Prophylactic treatment exposes a large proportion of infants unnecessarily to a drug that has important side effects without conferring any important short-term benefits. Current evidence does not support the use of ibuprofen for prevention of patent ductus arteriosus. Until long-term follow-up results of the trials included in this review have been published, no further trials of prophylactic ibuprofen are recommended. A new approach to patent ductus arteriosus management is an early targeted treatment based on echocardiographic criteria within the first 72 hours of life, that have a high sensitivity for diagnosing a patent ductus arteriosus that is unlikely to close spontaneously. Such trials are currently ongoing in many parts of the world. Results of such trials will be included in updates of our "Ibuprofen for treatment of PDA" review.

Ibuprofen for the prevention of patent ductus arteriosus in preterm and/or low birth weight infants

BACKGROUND

Patent ductus arteriosus (PDA) complicates the clinical course of preterm infants and increases the risk of adverse outcomes. Indomethacin has been the standard treatment to close a PDA but is associated with renal, gastrointestinal, and cerebral side effects. Ibuprofen has less effect on blood flow velocity to important organs.

OBJECTIVES

Primary objectivesTo determine the effectiveness and safety of ibuprofen compared to placebo/no intervention, or other cyclo-oxygenase inhibitor drugs in the prevention of PDA in preterm infants.

SEARCH METHODS

We used the standard search strategy of Cochrane Neonatal to search the Cochrane Central Register of Controlled Trials (CENTRAL; 2018, Issue 10), MEDLINE via PubMed (1966 to 17 October 2018), Embase (1980 to 17 October 2018), and CINAHL; 1982 to 17 October 2018). We searched clinical trials databases, conference proceedings, and the reference lists of retrieved articles for randomised controlled trials and quasi-randomised trials.

SELECTION CRITERIA

Randomised and quasi-randomised controlled trials comparing ibuprofen with placebo/no intervention or other cyclo-oxygenase inhibitor drugs to prevent PDA in preterm or low birth weight infants.

DATA COLLECTION AND ANALYSIS

We extracted outcomes data including presence of PDA on day three or four of life (after 72 hours of treatment), need for surgical ligation or rescue treatment with cyclo-oxygenase inhibitors, mortality, cerebral, renal, pulmonary, and gastrointestinal complications. We performed meta-analyses and reported treatment estimates as typical mean difference (MD), risk ratio (RR), risk difference (RD) and, if statistically significant, number needed to treat to benefit (NNTB) or to harm (NNTH), along with their 95% confidence intervals (CI). We assessed between-study heterogeneity by the I-squared test (I²). We used the GRADE approach to assess the quality of evidence.

MAIN RESULTS

In this updated analysis, we included nine trials (N = 1070 infants) comparing prophylactic ibuprofen (IV or oral) with placebo/no intervention or indomethacin. Ibuprofen (IV or oral) probably decreases the risk of PDA on day 3 or 4 (typical RR 0.39, 95% CI 0.31 to 0.48; typical RD -0.26, 95% CI -0.31 to -0.21; NNTB 4, 95% CI 3 to 5; 9 trials; N = 1029) (moderate-quality evidence). In the control group, the spontaneous closure rate was 58% by day 3 to 4 of age. In addition, ibuprofen probably decreases the need for rescue treatment with cyclo-oxygenase inhibitors (typical RR 0.17, 95% CI 0.11 to 0.26; typical RD -0.27, 95% CI -0.32 to -0.22; NNTB 4; 95% CI 3 to 5),and the need for surgical ductal ligation (typical RR 0.46, 95% CI 0.22 to 0.96; typical RD -0.03, 95% CI -0.05 to -0.00; NNTB 33, 95% CI 20 to infinity; 7 trials; N = 925) (moderate-quality evidence). There was a possible decrease in the risk of grade 3 or 4 intraventricular haemorrhage (IVH) in infants receiving prophylactic ibuprofen (typical RR 0.67, 95% CI 0.45 to 1.00; I² = 34%; typical RD -0.04, 95% CI -0.08 to- 0.00; I² = 60%; 7 trials; N = 925) (moderate-quality evidence). High quality evidence showed increased risk for oliguria (typical RR 1.45, 95% CI 1.04 to 2.02; typical RD 0.06, 95% CI 0.01 to 0.11; NNTH 17, 95% CI 9 to 100; 4 trials; N = 747). Low quality results from four studies (N = 202) showed that administering oral ibuprofen may decrease the risk of PDA (typical RR 0.47, 95% CI 0.30 to 0.74) and may increase risk of gastrointestinal bleeding (NNTH 7, 95% CI 4 to 25). No evidence of a difference was identified for mortality, any intraventricular haemorrhage (IVH), or chronic lung disease.

AUTHORS' CONCLUSIONS

This review shows that prophylactic use of ibuprofen, compared to placebo or no intervention, probably decreases the incidence of patent ductus arteriosus, the need for rescue treatment with cyclo-oxygenase inhibitors, and for surgical ductal closure. Adverse effects associated with ibuprofen (IV or oral) included increased risks for oliguria, increase in serum creatinine levels, and increased risk of gastrointestinal haemorrhage. There was a reduced risk for intraventricular haemorrhage (grade III - IV) but no evidence of a difference in mortality, chronic lung disease, necrotising enterocolitis, or time to reach full feeds. In the control group, the patent ductus arteriosus had closed spontaneously by day 3 or 4 in 58% of neonates. Prophylactic treatment exposes a large proportion of infants unnecessarily to a drug that has important side effects without conferring any important short-term benefits. Current evidence does not support the use of ibuprofen for prevention of patent ductus arteriosus. Until long-term follow-up results of the trials included in this review have been published, no further trials of prophylactic ibuprofen are recommended.A new approach to patent ductus arteriosus management is an early targeted treatment based on echocardiographic criteria within the first 72 hours of life, that have a high sensitivity for diagnosing a patent ductus arteriosus that is unlikely to close spontaneously. Such trials are currently ongoing in many parts of the world. Results of such trials will be included in updates of our "Ibuprofen for treatment of PDA" review.

Trends and variation in management and outcomes of very low-birth-weight infants with patent ductus arteriosus

BACKGROUND

We examined recent trends and interhospital variation in use of indomethacin, ibuprofen, and surgical ligation for patent ductus arteriosus (PDA) in very-low-birth-weight (VLBW) infants.

METHODS

Included in this retrospective study of the Pediatric Hospital Information System database were 13,853 VLBW infants from 19 US children's hospitals, admitted at age < 3 d between 1 January 2005 and 31 December 2014. PDA management and in-hospital outcomes were examined for trends and variation.

RESULTS

PDA was diagnosed in 5,719 (42%) VLBW infants. Cyclooxygenase inhibitors and/or ligation were used in 74% of infants with PDA overall, however studied hospitals varied greatly in PDA management. Odds of any cyclooxygenase inhibitor or surgical treatment for PDA decreased 11% per year during the study period. This was temporally associated with improved survival but also with increasing bronchopulmonary dysplasia, periventricular leukomalacia, retinopathy of prematurity, and acute renal failure in unadjusted analyses. There was no detectable correlation between hospital-specific changes in PDA management and hospital-specific changes in outcomes of preterm birth during the study period.

CONCLUSION

Use of cyclooxygenase inhibitors and ligation for PDA in VLBW infants decreased over a 10-y period at the studied hospitals. Further evidence is needed to assess the impact of this change in PDA management.

Management of patent ductus arteriosus in premature infants

Patency of the ductus arteriosus is required for fetal survival in utero. In infants born prematurely, ductus fails to close and shunt reverses from left to right. Incidence of patent ductus arteriosus (PDA) is inversely proportional to the gestational age. A large PDA (>1.5 mm diameter) with left to right shunt in very low birth weight infants can cause pulmonary edema, congestive heart failure, pulmonary hemorrhage and increase the risk for bronchopulmonary dysplasia. Attempts to prevent or close the duct by pharmacological or surgical methods have not changed the morbidity or the long term outcome. Pharmacological treatment with indomethacin or ibuprofen is successful in 75 to 80 % of infants but its use also exposes these infants to undesirable side effects like gastrointestinal bleeding, perforation and necrotizing enterocolitis. Prophylactic therapy with indomethacin or ibuprofen to prevent PDA has not altered the morbidity or long term outcome. Currently, there is a dilemma as to how to treat, when to treat and whom to treat. Recent literature suggests a trial of conservative management during the first week followed by selective use of anti-inflammatory drugs. Surgical ligation is reserved for infants who fail medical therapy and still remain symptomatic. Spontaneous closure of the PDA has been reported in up to 40-67 % of very low birth weight (VLBW) infants by 7 d. In this review authors discuss these controversies and propose a more rational approach.

Differential renal adverse effects of ibuprofen and indomethacin in preterm infants: a review

OBJECTIVE

The objective of this study was to evaluate the extent of renal adverse effects caused by ibuprofen or indomethacin in order to choose the safer drug to administer to preterm infants.

METHODS

THE FOLLOWING THREE PARAMETERS OF RENAL FUNCTION WERE TAKEN INTO CONSIDERATION: 1) the urine output; 2) the serum creatinine concentration; and 3) the frequency of oliguria. The bibliographic search was performed using PubMed and Embase databases as search engines.

RESULTS

Urine output ranged from 3.5±1.2 to 4.0±1.4 mL/kg/h after ibuprofen treatment, and from 2.8±1.1 to 3.6±1.4 mL/kg/h after indomethacin treatment. The values for ibuprofen are significantly (P<0.05) higher than those for indomethacin. The serum creatinine concentrations ranged from 0.98±0.24 to 1.48±0.2 mg/dL after ibuprofen treatment, and from 1.06±0.24 and 2.03±2.10 mg/dL after indomethacin treatment. The values for ibuprofen are significantly (P<0.05) lower than those for indomethacin. The frequency of oliguria ranged from 1.0% to 9.6% (ibuprofen) and from 14.8% to 40.0% (indomethacin), and was significantly lower following ibuprofen than indomethacin administration. In infants with body weight lower than 1,000 g, oliguria appeared in 5% (ibuprofen) and 40% (indomethacin; P=0.02).

CONCLUSION

Indomethacin is associated with more severe renal adverse effects than ibuprofen. Ibuprofen is less nephrotoxic than indomethacin and should be used to treat patent ductus arteriosus in preterm infants. Immaturity increases the frequency of adverse effects of indomethacin.

The Association between Patent Ductus Arteriosus and Perinatal Infection in A Group of Low Birth Weight Preterm Infants

OBJECTIVE

Patent ductus arteriosus (PDA) is an extremely common occurrence in very premature infants. Untreated symptomatic PDA may be associated with chronic lung disease. PDA has a major role in neonatal mortality and morbidity. We compared the efficacy and safety of oral versus intravenous ibuprofen for the pharmacological closure of PDA in low birth weight (LBW) preterm infants.

METHODS

A randomized, single-blinded, controlled study was performed on premature neonates at the neonatal unit, University Hospital for Obstetrics and Gynecology "Koço Gliozheni", Tirana, Albania from January 2010 to December 2012. The study enrolled 68 preterm infants with a confirmed and significant PDA. The preterm infants received either intravenous or oral ibuprofen randomly as an initial dose of 10 mg/kg, followed by 5 mg/kg at 24 and 48 h. Findings : 36 patients were treated with oral ibuprofen and 32 with intravenous ibuprofen during this period. After the first course of the treatment, the PDA closed in 30 (83.3%) of the patients assigned to the oral ibuprofen group versus 23 (71.8%) of those enrolled in the intravenous ibuprofen group (P=0.355). 15 patiens needed a second treatment course and they all (100%) had clinical signs of infection and positive blood culture. There was no reopening of the ductus after the closure.

CONCLUSION

Our data indicate that, for LBW infants, the rate of early ductal closure was comparable and the adverse effects were fewer with oral ibuprofen in comparison to the intravenous route. Association of PDA with perinatal infection has a negative impact in pharmacological closure of the ductus, increasing the need for a second course of treatment or for surgery.

Patent ductus arteriosus in preterm infants: do we have the right answers?

Patent ductus arteriosus (PDA) is a common clinical condition in preterm infants. Preterm newborns with PDA are at greater risk for several morbidities, including higher rates of bronchopulmonary dysplasia (BPD), decreased perfusion of vital organs, and mortality. Therefore, cyclooxygenase (COX) inhibitors and surgical interventions for ligation of PDA are widely used. However, these interventions were reported to be associated with side effects. In the absence of clear restricted rules for application of these interventions, different strategies are adopted by neonatologists. Three different approaches have been investigated including prophylactic treatment shortly after birth irrespective of the state of PDA, presymptomatic treatment using echocardiography at variable postnatal ages to select infants for treatment prior to the duct becoming clinically significant, and symptomatic treatment once PDA becomes clinically apparent or hemodynamically significant. Future appropriately designed randomized controlled trials (RCTs) to refine selection of patients for medical and surgical treatments should be conducted. Waiting for new evidence, it seems wise to employ available clinical and echocardiographic parameters of a hemodynamically significant (HS) PDA to select patients who are candidates for medical treatment. Surgical ligation of PDA could be used as a back-up tool for those patients who failed medical treatment and continued to have hemodynamic compromise.

An Interesting Observation of PDA Closure with Oral Paracetamol in Preterm Neonates

Patent ductus arteriosus (PDA), in which there is a persistent communication between the descending thoracic aorta and the pulmonary artery that results from failure of normal physiologic closure of the fetal ductus, is one of the more common congenital heart defects in preterm neonates. The closure of PDA can be done with either Indomethacin or Brufen which are cyclooxygenase 1, 2 inhibitor; however these drugs are associated with side effects. We report an interesting findings of ductal closure in 10 preterm neonates (gestational age 27-33 wks) presenting with significant large PDA who had failed or had absolute contraindication with Brufen. These preterm neonates were treated with oral paracetamol in the dose of 15 mg/kg 8 hourly. The PDA closure was achieved within 48 h and there was no complication.

Early echocardiographic prediction of ductal closure in neonates ≤ 30 weeks gestation

OBJECTIVE

To determine the accuracy of the patent ductus arteriosus:left pulmonary artery ratio (PDA:LPA) on echocardiogram (ECHO) at 3-day postnatal in predicting spontaneous PDA closure in neonates ≤ 30 weeks gestational age (GA).

STUDY DESIGN

ECHOs were performed at 72 h to characterize PDA size as closed-to-small (PDA:LPA <0.5) or moderate-to-large (PDA:LPA ≥ 0.5) and at 10 days to determine spontaneous closure (defined as closed-to-small in the absence of medical and/or surgical treatment). Caretakers were blinded to results; treatment was based on standard care. Neonates were prospectively enrolled and stratified: <27 weeks (n=31) and 27 to 30 weeks (n=65).

RESULT

Neonates <27 weeks with closed-to-small PDAs had 60% spontaneous closure vs 9% when moderate-to-large (positive predictive value (PPV) 60%, negative predictive value (NPV) 91%). Neonates 27 to 30 weeks had 95% spontaneous closure vs 27%, respectively (PPV 95%, NPV 73%). Inter-observer variability for the initial ECHO was 0.84.

CONCLUSION

PDA size defined by PDA:LPA at 3 days postnatal in combination with GA predicts spontaneous PDA closure.

Predictors of bronchopulmonary dysplasia

Although significant advances in respiratory care have been made in neonatal medicine, bronchopulmonary dysplasia (BPD) remains the most common serious pulmonary morbidity in premature infants. The development of BPD is the result of the complex interactions between multiple perinatal and postnatal factors. Early identification of infants at the most risk of developing BPD through the use of estimators and models may allow a targeted approach at reducing BPD in the future.

Preterm patent ductus arteriosus: should we treat it?

Debate about the importance of the preterm patent ductus arteriosus (PDA) remains unresolved. Ultrasound studies of PDA have suggested that the haemodynamic impact may be much earlier after birth than previously thought, but we still do not know when to treat a PDA. Studies that have tested symptomatic or pre-symptomatic treatment are mainly historical and have not tested the effect of no treatment. Prophylactic treatment is the best studied regimen, but improvements in some short-term outcomes do not translate to any difference in longer term outcomes. Neonatologists have been reluctant to engage in trials that test treatment against not treating at all or very rarely. Targeting treatment on the basis of the early post-natal constrictive response of the duct is currently being tested as a possible strategy.

Ibuprofen for the prevention of patent ductus arteriosus in preterm and/or low birth weight infants

BACKGROUND

Patent ductus arteriosus (PDA) complicates the clinical course of preterm infants and increases the risk of adverse outcomes. Indomethacin has been the standard treatment to close a PDA but is associated with renal, gastrointestinal and cerebral side-effects. Ibuprofen has less effect on blood flow velocity to important organs.

OBJECTIVES

To determine the effectiveness and safety of prophylactic ibuprofen compared to placebo/no intervention in the prevention of PDA in preterm infants.

SEARCH STRATEGY

Randomized controlled trials of prophylactic ibuprofen were identified by searching in The Cochrane Library, MEDLINE, CINAHL, EMBASE and trials registries in December 2010.

SELECTION CRITERIA

Randomized or quasi-randomised controlled trials comparing ibuprofen with placebo/no intervention or other cyclo-oxygenase inhibitor drugs to prevent PDA in preterm and/or low birth weight infants.

DATA COLLECTION AND ANALYSIS

Outcomes data including presence of PDA on day three, need for surgical ligation or rescue treatment with cyclo-oxygenase inhibitors, mortality, intraventricular haemorrhage (IVH), renal, pulmonary and gastrointestinal complications were extracted. Meta-analyses were performed and treatment estimates are reported as typical weighted mean difference, relative risk (RR), risk difference (RD) and, if statistically significant, number needed to treat to benefit (NNT) or number needed to treat to harm (NNH) along with their 95% confidence intervals (CI).

MAIN RESULTS

In this update, seven studies (n = 931) comparing prophylactic ibuprofen with placebo/no intervention are included. Ibuprofen decreased the incidence of PDA on day three [typical RR 0.36 (95% CI 0.29 to 0.46); typical RD -0.27 (95% CI -0.32 to -0.21); NNT 4 (95% CI 3 to 5)], decreased the need for rescue treatment with cyclo-oxygenase inhibitors and decreased the need for surgical ligation. Results from two studies administering oral ibuprofen had similar results, but showed an increased risk of gastrointestinal bleeding (NNH 4, 95% CI 2 to 17). In the control group the spontaneous closure rate was 58% by day three. Ibuprofen negatively affects renal function. No significant differences in mortality, IVH, chronic lung disease were found.

AUTHORS' CONCLUSIONS

Prophylactic use of ibuprofen decreased the incidence of PDA, decreased the need for rescue treatment with cyclo-oxygenase inhibitors and decreased the need for surgical closure. In the control group, the PDA closed spontaneously by day three in 58% of the neonates. Prophylactic treatment exposes many infants to a drug that has concerning renal and gastrointestinal side effects without conferring any important short-term benefits and is not recommended. Until long-term follow-up results are published from the trials included in this updated review, no further trials of prophylactic ibuprofen are recommended.

Learning to live with patency of the ductus arteriosus in preterm infants

Treatment of persistent patency of the ductus arteriosus in preterm infants remains heterogeneous and controversial. Routine early treatment to induce ductal closure is not beneficial, but the potential criteria for, timing of, methods for and benefits of later ductal closure have not been determined. Management strategies for infants awaiting spontaneous closure or meeting criteria for treatment may be based on pathophysiological considerations but require evaluation in clinical trials. Better diagnostic tools allowing the identification of infants who might benefit from ductal closure, supplemented by data from clinical trials confirming realization of that potential, are urgently needed.

Should we definitively abandon prophylaxis for patent ductus arteriosus in preterm new-borns?

Although the prophylactic administration of indomethacin in extremely low-birth weight infants reduces the frequency of patent ductus arteriosus and severe intraventricular hemorrhage, it does not appear to provide any long-term benefit in terms of survival without neurosensory and cognitive outcomes. Considering the increased drug-induced reduction in renal, intestinal, and cerebral blood flow, the use of prophylaxis cannot be routinely recommended in preterm neonates. However, a better understanding of the genetic background of each infant may allow for individualized prophylaxis using NSAIDs and metabolomics.

Prophylactic intravenous indomethacin for preventing mortality and morbidity in preterm infants

BACKGROUND

Persistent patent ductus arteriosus (PDA) is associated with mortality and morbidity in preterm infants. Prostaglandin synthetase inhibitors such as indomethacin promote PDA closure but also have potential side effects. The effect of the prophylactic use of indomethacin, where infants who may not have gone on to develop a symptomatic PDA would be exposed to indomethacin, warrants particular scrutiny.

OBJECTIVES

To determine the effect of prophylactic indomethacin on mortality and morbidity in preterm infants.

SEARCH STRATEGY

The standard search strategy of the Cochrane Neonatal Review Group was used. This included searches of the Cochrane Central Register of Controlled Trials (CENTRAL, The Cochrane Library, Issue 5, 2010), MEDLINE, EMBASE and CINAHL (until April 2010), conference proceedings, and previous reviews.

SELECTION CRITERIA

Randomised or quasi-randomised controlled trials that compared prophylactic indomethacin versus placebo or no drug in preterm infants.

DATA COLLECTION AND ANALYSIS

The standard methods of the Cochrane Neonatal Review Group were used, with separate evaluation of trial quality and data extraction by two review authors.

MAIN RESULTS

Nineteen eligible trials in which 2872 infants participated were identified. Most participants were very low birth weight, but the largest single trial restricted participation to extremely low birth weight infants (N = 1202). The trials were generally of good quality.The incidence of symptomatic PDA [typical relative risk (RR) 0.44, 95% confidence interval (CI) 0.38 to 0.50] and PDA surgical ligation (typical RR 0.51, 95% CI 0.37,0.71) was significantly lower in treated infants. Prophylactic indomethacin also significantly reduced the incidence of severe intraventricular haemorrhage (typical RR 0.66, 95% CI 0.53 to 0.82). Meta-analyses found no evidence of an effect on mortality (typical RR 0.96, 95% CI 0.81 to 1.12) or on a composite of death or severe neurodevelopmental disability assessed at 18 to 36 months old (typical RR 1.02, 95% CI 0.90, 1.15).

AUTHORS' CONCLUSIONS

Prophylactic indomethacin has short-term benefits for preterm infants including a reduction in the incidence of symptomatic PDA, PDA surgical ligation, and severe intraventricular haemorrhage. However, there is no evidence of effect on mortality or neurodevelopment.

Treatment of persistent patent ductus arteriosus in preterm infants: time to accept the null hypothesis?

Medical and surgical interventions are widely used to close a persistently patent ductus arteriosus in preterm infants. Objective evidence to support these practices is lacking, causing some to question their usage. Emerging evidence suggests that treatments that close the patent ductus may be detrimental. This review examines the history of and evidence underlying these treatments. Neither individual trials, pooled data from groups of randomized-controlled trials, nor critical examination of the immediate consequences of treatment provide evidence that medical or surgical closure of the ductus is beneficial in preterm infants. These conclusions are supported by sufficient evidence. Neither continued routine use of these treatments nor additional clinical trials using similar designs seems to be justified. A definitive trial, comparing current standard management with novel strategies not primarily intended to achieve ductal closure, may be necessary to resolve doubts regarding the quality or conduct of prior studies.

Nonsteroidal Anti-Inflammatory Drugs: A survey of practices and concerns of pediatric medical and surgical specialists and a summary of available safety data

OBJECTIVES

To examine the prescribing habits of NSAIDs among pediatric medical and surgical practitioners, and to examine concerns and barriers to their use.

METHODS

A sample of 1289 pediatricians, pediatric rheumatologists, sports medicine physicians, pediatric surgeons and pediatric orthopedic surgeons in the United States and Canada were sent an email link to a 22-question web-based survey.

RESULTS

338 surveys (28%) were completed, 84 were undeliverable. Of all respondents, 164 (50%) had never prescribed a selective cyclooxygenase-2 (COX-2) NSAID. The most common reasons for ever prescribing an NSAID were musculoskeletal pain, soft-tissue injury, fever, arthritis, fracture, and headache. Compared to traditional NSAIDs, selective COX-2 NSAIDs were believed to be as safe (42%) or safer (24%); have equal (52%) to greater efficacy (20%) for pain; have equal (59%) to greater efficacy (15%) for inflammation; and have equal (39%) to improved (44%) tolerability. Pediatric rheumatologists reported significantly more frequent abdominal pain (81% vs. 23%), epistaxis (13% vs. 2%), easy bruising (64% vs. 8%), headaches (21% vs. 1%) and fatigue (12% vs. 1%) for traditional NSAIDs than for selective COX-2 NSAIDs. Prescribing habits of NSAIDs have changed since the voluntary withdrawal of rofecoxib and valdecoxib; 3% of pediatric rheumatologists reported giving fewer traditional NSAID prescriptions, and while 57% reported giving fewer selective COX-2 NSAIDs, 26% reported that they no longer prescribed these medications.

CONCLUSIONS

Traditional and selective COX-2 NSAIDs were perceived as safe by pediatric specialists. The data were compared to the published pediatric safety literature.

Genetic contribution to patent ductus arteriosus in the premature newborn

BACKGROUND

The most common congenital heart disease in the newborn population, patent ductus arteriosus, accounts for significant morbidity in preterm newborns. In addition to prematurity and environmental factors, we hypothesized that genetic factors play a significant role in this condition.

OBJECTIVE

The objective of this study was to quantify the contribution of genetic factors to the variance in liability for patent ductus arteriosus in premature newborns.

PATIENTS AND METHODS

A retrospective study (1991-2006) from 2 centers was performed by using zygosity data from premature twins born at < or =36 weeks' gestational age and surviving beyond 36 weeks' postmenstrual age. Patent ductus arteriosus was diagnosed by echocardiography at each center. Mixed-effects logistic regression was used to assess the effect of specific covariates. Latent variable probit modeling was then performed to estimate the heritability of patent ductus arteriosus, and mixed-effects probit modeling was used to quantify the genetic component.

RESULTS

We obtained data from 333 dizygotic twin pairs and 99 monozygotic twin pairs from 2 centers (Yale University and University of Connecticut). Data on chorioamnionitis, antenatal steroids, gestational age, body weight, gender, respiratory distress syndrome, patent ductus arteriosus, necrotizing enterocolitis, oxygen supplementation, and bronchopulmonary dysplasia were comparable between monozygotic and dizygotic twins. We found that gestational age, respiratory distress syndrome, and institution were significant covariates for patent ductus arteriosus. After controlling for specific covariates, genetic factors or the shared environment accounted for 76.1% of the variance in liability for patent ductus arteriosus.

CONCLUSIONS

Preterm patent ductus arteriosus is highly familial (contributed to by genetic and environmental factors), with the effect being mainly environmental, after controlling for known confounders.

Oral-ibuprofen-induced acute renal failure in a preterm infant

The side effects of indomethacin for ductal closure in preterm neonates (e.g. increased incidence of necrotizing enterocolitis, decreased cerebral blood volume and transient renal failure) have led clinicians to seek a safer alternative. Intravenous indomethacin and ibuprofen appear to be equally effective for patent ductus arteriosus closure, but oral ibuprofen remains an experimental option with theoretical advantages yet with potential side effects. We herein report a case of transient but severe acute renal failure developing in a preterm infant in whom oral ibuprofen was used and discuss the safety of this drug in relation to its pharmacokinetics.

Nephrotoxicity as a cause of acute kidney injury in children

Many different drugs and agents may cause nephrotoxic acute kidney injury (AKI) in children. Predisposing factors such as age, pharmacogenetics, underlying disease, the dosage of the toxin, and concomitant medication determine and influence the severity of nephrotoxic insult. In childhood AKI, incidence, prevalence, and etiology are not well defined. Pediatric retrospective studies have reported incidences of AKI in pediatric intensive care units (PICU) of between 8% and 30%. It is widely recognized that neonates have higher rates of AKI, especially following cardiac surgery, severe asphyxia, or premature birth. The only two prospective studies in children found incidence rates of 4.5% and 2.5% of AKI in children admitted to PICU, respectively. Nephrotoxic drugs account for about 16% of all AKIs most commonly associated with AKI in older children and adolescents. Nonsteroidal anti-inflammatory drugs (NSAIDs), antibiotics, amphotericin B, antiviral agents, angiotensin-converting enzyme (ACE) inhibitors, calcineurin inhibitors, radiocontrast media, and cytostatics are the most important drugs to indicate AKI as significant risk factor in children. Direct pathophysiological mechanisms of nephrotoxicity include constriction of intrarenal vessels, acute tubular necrosis, acute interstitial nephritis, and-more infrequently-tubular obstruction. Furthermore, AKI may also be caused indirectly by rhabdomyolysis. Frequent therapeutic measures consist of avoiding dehydration and concomitant nephrotoxic medication, especially in children with preexisting impaired renal function.

Patent ductus arteriosus: lack of evidence for common treatments

Patent ductus arteriosus (PDA) is a common diagnosis among extremely premature infants, especially in those with lung disease. Treatments are often used to close the PDA. Despite nearly three decades of research, the question of whether the benefits of treatments to prevent ductal patency or promote closure outweigh the risks of these treatments remains unanswered. The authors rarely use treatments designed to close the PDA. This article reviews three considerations in support of this restrained approach: rates of spontaneous closure of the ductus arteriosus; adverse effect of persistent ductal patency; and benefits and risks of treatments for closure.

Clinical considerations for the pharmacologic management of patent ductus arteriosus with cyclooxygenase inhibitors in premature infants

When medical management is warranted for closure of a persistent patent ductus arteriosus (PDA) in premature infants, treatment with a cyclooxygenase (COX) inhibitor is indicated. Indomethacin, available since 1976, has been the conventional pharmacologic treatment for PDA, but its use is associated with vasoconstrictive effects that impair renal, mesenteric and cerebral blood flow. Intravenous (IV) ibuprofen lysine, approved in the United States in 2006, has less severe vasoconstrictive effects on these vital organs than IV indomethacin. Clinical trials have shown both of these COX inhibitors to be equally effective in closing the PDA in approximately 70%-80% of treated infants, with less vasoconstrictive and adverse renal effects occurring with IV ibuprofen lysine.1,2 Several clinical considerations are important in the process of medical decision-making when faced with the need for PDA treatment with one of these pharmacologic agents in the premature infant. This paper focuses on these clinical considerations, including cerebral, renal and mesenteric blood flow, renal function, pulmonary effects, protein-binding capacity as it relates to hyperbilirubinemia, and platelet aggregation. No differences in chronic lung disease, pulmonary hypertension, hyperbilirubinemia and coagulopathy were observed in clinical trials when comparing these 2 COX inhibitors; however, significant differences have been observed in arterial blood flow to the cerebral, renal and mesenteric organs, suggesting that IV ibuprofen lysine may be the more favorable agent.

Clinical experience with intravenous Ibuprofen lysine in the pharmacologic closure of patent ductus arteriosus

Patent ductus arteriosus (PDA) is the failure of the ductus that arises from the distal dorsal aortic arch to close during the first few days of life. The treatment options for PDA include "watchful waiting," pharmacologic therapy with cyclooxygenase (COX) inhibitors (COX-1 and COX-2), such as indomethacin or intravenous (IV) ibuprofen lysine, and surgery when medical interventions have proved ineffective. The clinical trials evaluating the utilization of IV ibuprofen lysine focus on either preventing the persistence of a PDA or treating the PDA in premature infants in whom the ductus does not close within 48 hours of birth. Although the role of COX inhibitors in prophylaxis of PDA has been studied, it has not been clearly delineated. Treatment of PDA in preterm low birth weight infants from the second day of life on with IV ibuprofen lysine has been studied in 4 major and 3 smaller clinical trials. Overall, in 7 studies with 492 patients, the closure rate of PDA was 75.1% with IV ibuprofen lysine compared to 73.5% with indomethacin. In addition, neonates treated with IV ibuprofen lysine had significantly better creatinine clearance, urine output, serum creatinine, and blood urea nitrogen (BUN) profiles than indomethacin-treated patients. Overall, IV ibuprofen lysine is as effective as indomethacin for closure of PDA, yet is associated with a better safety profile with fewer negative side effects when compared to indomethacin.

Common clinical and practical questions on the use of intravenous Ibuprofen lysine for the treatment of patent ductus arteriosus

Cyclooxygenase inhibitors have proven efficacy in the treatment of patent ductus arteriosus (PDA). Intravenous indomethacin has been the only approved treatment for PDA available in the United States for the past 20 years. The armamentarium has recently been expanded with the approval of intravenous ibuprofen lysine in 2006. Ibuprofen lysine has been used for years in Europe, and the author reviews the extensive published literature. This review addresses common questions about ibuprofen lysine, summarizes the available literature, and discusses the data submitted to the Food and Drug Administration (FDA) in support of its approval. Three major trials served as the approval basis for the safety and efficacy of ibuprofen lysine. The author has summarized these studies and, where appropriate, presents pooled results from additional analyses that have not been previously published. Many practical questions regarding the drug, including dosing, administration, and storage are addressed. The results of recently completed but unpublished tests on stability and compatibility with commonly used drugs in the neonatal setting are also reviewed. Ibuprofen lysine now represents an alternative pharmacological option to surgery for the treatment of PDA.

Intravenous indomethacin for preventing mortality and morbidity in very low birth weight infants

BACKGROUND

This section is under preparation and will be included in the next issue.

OBJECTIVES

Indomethacin is used to treat symptomatic patent ductus arteriosus and may prevent or limit intraventricular haemorrhage in the neonatal period. This review examines the effectiveness of prophylactic intravenous indomethacin in reducing the mortality and morbidity associated with these conditions in infants weighing less than 1750 grams at birth.

SEARCH STRATEGY

A literature search from January 1980 to October 1994 was made in three computerised data bases: Medline; Embase; and the Oxford Database of Perinatal Trials. The search was updated in February 1997.

SELECTION CRITERIA

Strict selection criteria were applied to clinical trials: the population had to be newborn infants of birth weight < 1751 grams; the intervention had to be prophylactic intravenous indomethacin; the trial had to be randomised and controlled; and at least one of several prespecified outcomes had to be reported in the results.

DATA COLLECTION AND ANALYSIS

The methodological quality of each study was assessed using explicit criteria. Data on relevant outcome measures were extracted on two separate occasions and, where appropriate, the results of individual trials were combined using meta-analysis techniques to provide a pooled estimate of effect.

MAIN RESULTS

There is a trend towards reduced neonatal mortality in infants receiving prophylactic indomethacin, pooled relative risk (RR) = 0. 85 [95% CI 0.66 to 1.09]. The incidence of symptomatic patent ductus arteriosus is significantly reduced in treated infants, pooled RR = 0.35 [0.26 to 0.47] but there is no evidence that treatment affects respiratory outcomes. Prophylactic indomethacin significantly reduces the incidence of Grade 3 and 4 intraventricular haemorrhage in treated infants, pooled RR = 0.60 [0.43 to 0.83]. There is no evidence to suggest prophylactic indomethacin is associated with any long term adverse effect although there is a trend in treated infants towards an increased incidence of necrotizing enterocolitis, and some evidence that treatment may transiently impair renal function. There is no evidence that haemostasis is disturbed.

REVIEWER'S CONCLUSIONS

Prophylactic treatment with indomethacin has a number of immediate benefits, in particular a reduction in symptomatic patent ductus arteriosus and severe intraventricular haemorrhage. There is no evidence at present of long-term harm. Further trials are needed to assess more precisely the effects, both beneficial and harmful, on short and long-term outcomes.