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

Different interventions for the treatment of patent ductus arteriosus in children: a protocol for a network meta-analysis

INTRODUCTION

Patent ductus arteriosus (PDA) is one of the most common congenital heart diseases. Once the PDA is diagnosed, it needs to be dealt with in time. At present, main methods include pharmacological treatment, surgical closure, and interventional closure for treatment of PDA. However, the effect of different interventions in PDA management is still controversial. Thus, our study aims to assess the effectiveness of different interventions together and estimate the sequence of these therapies for PDA children. Meanwhile, it is necessary to conduct a Bayesian network meta-analysis to compare the safety of different interventions comprehensively.

METHODS AND ANALYSIS

To the best of our knowledge, this is the first Bayesian network meta-analysis comparing the efficacy and safety of different interventions for the treatment of PDA. PubMed, Embase, Cochrane Library, Web of Science, gray literature, and trial registry databases were searched from inception to December 2022. We will extract and report data according to methodological guidelines for Bayesian network meta-analysis by the Preferred Reporting Items for Systematic Reviews and Meta-Analyses Protocols (PRISMA-P). Primary PDA closure, overall PDA closure, technical success, surgical success rate, mortality during hospital stay, operation time, intensive care unit stay, intraoperative radiation dose, radiation exposure time, total postoperative complication rate, and postoperative major complication rate will be defined as the outcomes. The quality of all random studies will be assessed using ROB, and quality of evidence for all outcomes will be judged by using the Grading of Recommendations Assessment, Development and Evaluation (GRADE).

ETHICS AND DISSEMINATION

The results will be disseminated through peer-reviewed publication. Since no private and confidential patient data will be contained in the reporting, there are no ethical considerations associated with this protocol.

SYSTEMATIC REVIEW REGISTRATION

INPLASY2020110067.

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.

Evidence-based use of indomethacin and ibuprofen in the neonatal intensive care unit

Indomethacin and ibuprofen are potent inhibitors of prostaglandin synthesis. Neonates have been exposed to these compounds for more than 3 decades. Indomethacin is commonly used to prevent intraventricular hemorrhage (IVH), and both drugs are prescribed for the treatment or prevention of patent ductus arteriosus (PDA). This review examines the basis for indomethacin and ibuprofen use in the neonatal intensive care population. Despite the call for restrained use of each drug, the most immature infants are likely to need pharmacologic approaches to reduce high-grade IVH, avoid the need for PDA ligation, and preserve the opportunity for an optimal outcome.

Continuous infusion versus intermittent bolus doses of indomethacin for patent ductus arteriosus closure in symptomatic preterm infants

BACKGROUND

Indomethacin is a prostaglandin inhibitor used for the prevention and the treatment of patent ductus arteriosus (PDA). Although a 3-dose schedule has been commonly used, there is no consensus on optimal dosage and duration of indomethacin therapy for PDA closure. There are potential adverse effects of indomethacin use in premature infants such as a reduction in cerebral, mesenteric and renal blood flow and platelet dysfunction. Administering indomethacin continuously over 36-hours has been suggested as a safer and more effective option to prevent such adverse effects.

OBJECTIVES

To compare the efficacy and safety of continuous infusion versus bolus administration of indomethacin in closing a symptomatic PDA in preterm infants.

SEARCH STRATEGY

The standard search strategy of Cochrane Neonatal Review was used: MEDLINE and EMBASE (1966 - March 2007), Cochrane Central Register of Controlled Trials (CENTRAL, The Cochrane Library, Issue 1, 2007), bibliographies of reviews and trials were examined for references to other trials, previous symposia proceedings published in Pediatric Research (Pediatric Academic Societies Annual Meeting Abstract Book, 1972 - 2006). No language restrictions were applied.

SELECTION CRITERIA

Randomized and quasi-randomized controlled trials comparing continuous indomethacin infusion to bolus doses for closure of a symptomatic PDA in preterm infants with a symptomatic PDA diagnosed clinically and/or by echocardiography.

DATA COLLECTION AND ANALYSIS

The methodological quality of each study was assessed. Authors were contacted regarding missing data as well as to inquire about the outcomes that were not reported. Meta-analysis was performed to calculate relative risk (RR), risk difference (RD) and 95% confidence intervals (CI).

MAIN RESULTS

Only two small trials comparing continuous versus bolus indomethacin were eligible. Analysis of these studies showed that, although the primary outcome of PDA closure on days two and five slightly favored bolus administration, there was no statistical difference between the two groups. The estimates for PDA closure were RR 1.57 (95% CI 0.54, 4.60), RD 0.10 (95% CI -0.13, 0.33) for day 2 and RR 2.77 (95% CI 0.33, 23.14), RD 0.15 (95% CI -0.13, 0.42) for day five. There was no statistical difference between the bolus and continuous groups for the secondary outcomes of reopening of PDA, neonatal mortality, intraventricular hemorrhage (IVH) and necrotizing enterocolitis (NEC). These analyses were based on a very small number of events reported by these trials. None of the trials reported on outcomes such as requirement for retreatment with indomethacin or surgical ligation, mortality, bronchopulmonary dysplasia (BPD), retinopathy of prematurity (ROP), neurodevelopmental outcome and isolated intestinal perforation. The review demonstrated that there was a decrease in cerebral blood flow velocity after bolus injections and that the difference between the bolus and continuous infusion groups remained significant for 12 - 24 hour. In one study (Christmann 2002), the decrease in blood flow was maximum at 10 minutes [MD -46.40 (95% CI -75.41, -17.39)], while the other study (Hammerman 1995) reported a maximum drop at 30 minutes [MD -55.60 (95% CI -62.92, -48.28)]. Similar decrease in blood flow to the renal and mesenteric circulations following bolus administration was reported in one study (Christmann 2002). In both of these circulations, the decrease was maximum 30 minutes after the bolus injection [typical estimates for renal and mesenteric circulations, respectively: MD -42.00 (95% CI -76.59, -7.41) and MD -26.50 (95% CI -45.34, -7.66)] and lasted about two hours. None of the trials detected predefined levels of decreased urine output and increased levels of BUN and creatinine.

AUTHORS' CONCLUSIONS

Due to a paucity of events and lack of precision, the available data was found to be insufficient to draw conclusions regarding the efficacy of continuous indomethacin infusion versus bolus injections for the treatment of PDA. Although continuous indomethacin seems to cause less alterations in cerebral, renal and mesenteric circulations, the clinical meaning of this effect is unclear. Definitive recommendations about the preferred method of indomethacin administration i.e. continuous versus bolus infusions for the treatment of PDA in premature infants cannot be made based on the current findings of this review.

Conservative treatment for patent ductus arteriosus in the preterm

BACKGROUND

A patent ductus arteriosus (PDA) is common among preterms, and prophylactic medical treatment has been advocated as the first-line approach. Conservative treatment may result in similar outcome, but without exposure to the harmful side effects of medication. A retrospective analysis revealed a ductal closure rate of 94% after conservative treatment with adjustment of ventilation (lowering the inspiratory time and increasing positive end expiratory pressure) and fluid restriction.

OBJECTIVE

To study prospectively over one year the rate of PDA closure, and morbidity and mortality following conservative treatment.

METHOD

Prospective study (1 January 2005 - 31 December 2005) including 30 newborns <or=30 weeks' gestation, all of whom were being ventilated and required surfactant. Echocardiography was performed 48-72 h after birth. Clinically important PDA was conservatively treated as described above. The percentage of children with PDA, ductal ligation and major complications was determined.

RESULTS

Ten neonates (33%) developed a clinical important PDA. Following conservative treatment the duct closed in all neonates (100%), and none required ductal ligation or medical treatment. The rates of major complications were no higher than those reported by the Vermont Oxford Network and in the literature.

CONCLUSION

The managed care plan resulted in an overall ductal closure rate of 100%. These results suggest that conservative treatment of PDA is a worthy alternative to prophylactic medical treatment.

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.

Pharmacological therapy for analgesia and sedation in the newborn

Rapid advances have been made in the use of pharmacological analgesia and sedation for newborns requiring neonatal intensive care. Practical considerations for the use of systemic analgesics (opioids, non-steroidal anti-inflammatory agents, other drugs), local and topical anaesthetics, and sedative or anaesthetic agents (benzodiazepines, barbiturates, other drugs) are summarised using an evidence-based medicine approach, while avoiding mention of the underlying basic physiology or pharmacology. These developments have inspired more humane approaches to neonatal intensive care. Despite these advances, little is known about the clinical effectiveness, immediate toxicity, effects on special patient populations, or long-term effects after neonatal exposure to analgesics or sedatives. The desired or adverse effects of drug combinations, interactions with non-pharmacological interventions or use for specific conditions also remain unknown. Despite the huge gaps in our knowledge, preliminary evidence for the use of neonatal analgesia and sedation is available, but must be combined with a clear definition of clinical goals, continuous physiological monitoring, evaluation of side effects or tolerance, and consideration of long-term clinical outcomes.

Pulmonary hypertension following L-lysine ibuprofen therapy in a preterm infant with patent ductus arteriosus

Patent ductus arteriosus is one of the most common congenital abnormalities found in premature infants. Ibuprofen, a nonsteroidal drug that is commonly used as an antipyretic, analgesic and anti-inflammatory agent, is also used to induce closure of symptomatic patent ductus arteriosus in preterm infants. Recently, we gave L-lysine ibuprofen to a preterm infant with respiratory distress to induce closure of a patent ductus arteriosus, and the infant experienced pulmonary hypertension. Only 3 cases of pulmonary hypertension following early administration of an ibuprofen solution buffered with tromethamine have previously been reported. However, this severe side effect has never been observed in multicentre, randomized, double-blind controlled trials, nor in recent reviews or meta-analyses of L-lysine ibuprofen use.

Anesthesia and analgesia during and after surgery in neonates

BACKGROUND

Historically, the use of anesthetics and analgesics in neonates and infants has been based on extrapolations from studies performed in adults and older children. Over the past 20 years, there has been a growing body of research on the clinical pharmacology and clinical outcomes of these agents in neonates and infants.

OBJECTIVE

This article summarizes clinical pharmacology and clinical outcomes studies of opioids, opioid antagonists, sedative-hypnotics, nonsteroidal anti-inflammatory drugs and acetaminophen, and local anesthetics in neonates and infants to highlight gaps in the available knowledge, review some concerns about study design, and identify drugs that should receive high priority for future study.

METHODS

Relevant studies were identified through a search of MEDLINE and a review of textbooks, conference proceedings, and abstracts. The available literature was subjected to expert committee-based review.

CONCLUSIONS

There is a growing body of information on analgesic and anesthetic pharmacokinetics, pharmacodynamics, and clinical outcomes in neonates and infants, permitting safe and effective use in some clinical settings. Major gaps in knowledge persist, however. Future research may involve a combination of clinical trials and preclinical studies in suitable infant animal surrogate models.

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

BACKGROUND

A patent ductus arteriosus (PDA) often complicates the clinical course of preterm infants and increases the risk of intraventricular hemorrhage (IVH), necrotizing enterocolitis (NEC), chronic lung disease (CLD) and death. The standard treatment to close a PDA is indomethacin. Its use is associated with renal, gastrointestinal and cerebral side-effects. Ibuprofen has been shown to be effective in closing a PDA without reducing blood flow velocity to the brain, gut or kidneys.

OBJECTIVES

To determine the effectiveness and safety of prophylactic ibuprofen compared to placebo/no intervention or other cyclo-oxygenase inhibitor drugs (indomethacin, mefenamic acid, etc) in the prevention of PDA in preterm infants.

SEARCH STRATEGY

Randomized controlled trials comparing prophylactic ibuprofen use with placebo/no intervention/indomethacin were identified by searching the Cochrane Central Register of Controlled Trial (CENTRAL, The Cochrane Library, Issue 3, 2005), MEDLINE (1966-July 2005), CINAHL (1982-July 2005), EMBASE (1980-July 2005), reference lists of published trials and abstracts published in Pediatric Research (1990-July 2005). No language restrictions were applied.

SELECTION CRITERIA

Randomized or quasi-randomized controlled trials comparing use of ibuprofen with placebo/no intervention or other cyclo-oxygenase inhibitor drugs (indomethacin, mefenamic acid, etc) for the prevention of PDA in preterm and/or low birth weight infants.

DATA COLLECTION AND ANALYSIS

Data regarding the clinical outcomes including presence of PDA on day three and day seven, need for surgical ligation, need for rescue treatment with cyclo-oxygenase inhibitors, IVH, mortality, renal and gastrointestinal complications were extracted. Meta-analyses were performed using RevMan 4.2 and treatment estimates were reported as weighted mean difference (WMD), typical relative risk (RR), typical risk difference (RD) and, if statistically significant, number needed to treat (NNT) or number needed to harm (NNH), along with their 95% confidence intervals (CI).

MAIN RESULTS

Four trials (n = 672) were included in the review. There was a statistically significant decrease in the incidence of PDA on day three in the ibuprofen group [typical RR 0.37 (95% CI 0.29, 0.49); typical RD -0.29 (95% CI -0.35, -0.22); NNT 3 (95% CI 3, 5); 4 trials, n = 672], in the need for rescue treatment with cyclo-oxygenase inhibitors [typical RR 0.17 (95% CI 0.11, 0.27), typical RD -0.27 (95% CI -0.35, -0.22); NNT 4 (95%CI 3, 5), and in the need for surgical ligation [typical RR 0.34 (95% CI 0.14, 0.81), typical RD -0.04 (95% CI -0.07, -0.01); NNT 25 (95% CI 14, 100). The PDA had closed spontaneously by day three in 60% of the neonates in the control group. There was a significant increase in the serum creatinine levels in the ibuprofen group [WMD 0.13 mg/dl (95% CI 0.08, 0.17); 2 trials, n = 495]. Ibuprofen reduces urine output. There were no statistically significant differences in mortality, grade 3/4 intraventricular hemorrhage, chronic lung disease at 28 days or 36 weeks, necrotizing enterocolitis , gastrointestinal hemorrhage, intestinal perforation or time to reach full feeds. One trial (Gournay 2002) (n = 135) reported on three infants in the ibuprofen group who developed pulmonary hypertension responsive to nitric oxide treatment.

AUTHORS' CONCLUSIONS

Prophylactic use of ibuprofen reduces the incidence of PDA, the need for rescue treatment with cyclo-oxygenase inhibitors and surgical closure. However, in the control group, the PDA had closed spontaneously by day three in 60% of the neonates. Prophylactic treatment therefore exposes a large proportion of infants unnecessarily to a drug that has important side effects (mainly involving the kidneys) without conferring any important short term benefits. Prophylactic treatment with ibuprofen is not recommended. Until long-term follow-up results are published from the trials included in this review, no further trials of prophylactic ibuprofen are recommended.

Efecto de la administración concomitante de indometacina o ibuprofeno en la farmacocinética de amikacina en neonatos prematuros

OBJECTIVE

To evaluate whether the concomitant administration of ibuprofen or indomethacin plus amikacin may alter the latter drug s pharmacokinetic parameters, and hence amikacin plasma levels.

METHOD

Retrospective cohort study performed by reviewing the medical records of premature children with persistent ductus arteriosus receiving amikacin and ibuprofen, or amikacin and indomethacin. They were divided up into three groups: group 1: treatment with amikacin went before indomethacin or ibuprofen; group 2: simultaneously treated with amikacin and indomethacin; group 3: simultaneously treated with amikacin and ibuprofen. Pharmacokinetic parameters, distribution volume, and amikacin clearance were measured using the PKS program (a non-linear regression method). Half life was determined from previous parameters.

RESULTS

Twenty-eight patients were included. No statistically significant differences were found among pharmacokinetic parameters corresponding to each study group.

CONCLUSIONS

Further studies are needed with a greater number of patients and currently recommended doses to assess the influence of indomethacin and ibuprofen in the pharmacokinetics of amikacin in premature children with persistent ductus arteriosus.

Prophylactic ibuprofen for the prevention of intraventricular hemorrhage among preterm infants: a multicenter, randomized study

OBJECTIVE

Ibuprofen enhances cerebral blood flow autoregulation and was shown to protect neurologic functions after oxidative stresses in an animal model. For these reasons, we hypothesized that the prophylactic use of ibuprofen would reduce the occurrence of intraventricular hemorrhage (IVH) and its worsening toward grades 2 to 4 among preterm infants. To confirm this hypothesis, we planned the present prospective study.

METHODS

This was a double-blind, randomized, controlled trial in which preterm infants with gestational ages of <28 weeks received ibuprofen or placebo within the first 6 hours of life. The infants were assigned randomly, at 7 neonatal care units, to receive ibuprofen (10 mg/kg, followed by 5 mg/kg after 24 and 48 hours) or placebo. Serial echoencephalography was performed 24 and 48 hours after the initial cerebral ultrasound study, on postnatal days 7, 15, and 30, and at 40 weeks' postconceptional age. Grade 1 IVH or no IVH was considered a successful outcome, whereas grade 2 to 4 IVH represented failure. The rates of ductal closure, side effects, and complications were recorded.

RESULTS

We studied 155 infants. Grade 2 to 4 IVH developed for 16% of the ibuprofen-treated infants and 13% of the infants in the placebo group. The occurrence of patent ductus arteriosus was less frequent only on day 3 of life in the ibuprofen group. There were no significant differences with respect to other complications or adverse effects.

CONCLUSIONS

Our study demonstrated that prophylactic ibuprofen is ineffective in preventing grade 2 to 4 IVH and that its use for this indication cannot be recommended.

The pharmacologic closure of the patent ductus arteriosus

The ductus arteriosus is a fetal vessel that allows most of the blood leaving the right ventricle of the heart to bypass the lungs. Fetal patency of the ductus, and its spontaneous closure after birth, is the result of a balanced interaction of locally produced and circulating mediators (of which prostaglandins seem to be the most important), and the unique structure of the vessel wall. Persistent patency of the ductus occurs in almost 60% of very low birthweight infants. A significant left-to-right shunt through the ductus increases morbidity and mortality in premature infants. As prostaglandins play a major role in patency of the ductus, cyclooxygenase inhibitors are conventionally used to induce its closure. This chapter focuses on some of the basic mechanisms underlying ductal patency and the clinical attempts to diminish side effects associated with indomethacin, including the alternative use of ibuprofen.

Clinical measures to preserve cerebral integrity in preterm infants

Impaired psychomotor development, often anteceded by major intraventricular hemorrhage or periventricular leukomalacia, constitutes the most important long-term morbidity of very preterm infants. We reviewed randomized controlled trials aimed at reducing the incidence of brain damage, as detected by ultrasound, or neurodevelopmental impairment during follow-up of preterm infants. Preliminary reports of reduced rates of intraventricular hemorrhage obtained with administration of fresh frozen plasma, ethamsylate, phenobarbitone, or morphine have not been confirmed in subsequent larger trials. Early administration of indomethacin may reduce intraventricular hemorrhage without affecting long-term outcome. Pancuronium, inositol, and vitamin E decreased intraventricular hemorrhage rates but later psychomotor development was not examined. Thyroxin supplementation failed to improve neurodevelopmental outcome while protein enrichment of formula and individualized developmental care appear to be beneficial. The largest reductions in cerebral palsy and neurodevelopmental impairment were achieved by avoidance of postnatal steroids. This finding emphasizes the need to include these late endpoints in any randomized trial involving preterm infants.

Cyclooxygenase isoenzymes and patency of ductus arteriosus

Prenatal patency of the ductus arteriosus is maintained mainly by prostaglandin (PG) E(2). Accordingly, the vessel is endowed in its muscular component with a complete, cyclooxygenase (COX) and PGE synthase (PGES), system for the synthesis of the compound. COX1 is better expressed than COX2, particularly in the premature, but COX2 is more extensively coupled with microsomal PGES (mPGES). No evidence was obtained of either COX being coupled with cytosolic PGES (cPGES). Functionally, these data translate into a differential constrictor response of the ductus to dual, COX1/COX2, vs. COX2-specific inhibitors (indomethacin vs. L-745,337), with the latter being less effective specifically prior to term. This difference, however, subsides upon treatment with endotoxin and the attendant upregulation of COX2 and mPGES. Furthermore, when studied separately, COX1 and COX2 prove to be unevenly responsive to indomethacin, and an immediate and fast developing contraction of the vessel occurs only when COX2 is inhibited. Deletion of either COX gene results into upregulation of NO synthase, and a similar compensatory reaction is expected when enzymes are suppressed pharmacologically. We conclude that PGE(2) and NO can function synergistically in keeping the ductus patent. This arrangement provides a possible explanation for failures of indomethacin or ibuprofen treatment in the management of the prematurely born infant with persistent ductus. Coincidentally, it opens the way to new therapeutic possibilities being based on interference with the NO effector or a more selective disruption, possibly having mPGES as a target, of the PGE(2) synthetic cascade.