Surgical versus medical treatment with cyclooxygenase inhibitors for symptomatic patent ductus arteriosus in preterm infants

Pharmacological Benefits and Risk of Using Hormones in Organ Perfusion and Preservation Solutions in the Aspect of Minimizing Hepatic Ischemia-Reperfusion Injury during Storage

For several years, research has been carried out on the effectiveness of solutions for perfusion and preservation of organs, including the liver. There is a search for an optimal pharmacological composition of these solutions, allowing to preserve or improve vital functions of the organ for as long as possible until it is transplanted into a recipient. Hormones due to their properties, often resulting from their pleiotropic effects, may be a valuable component for optimizing the composition of liver perfusion and preservation solutions. The paper presents the current state of knowledge on liver perfusion and preservation solutions modified with hormones. It also shows the characteristics of the hormones evaluated, taking into account their physiological functions in the body.

Drug Closure of a Patent Ductus Arteriosus in An Extremely Low Birth Weight Premature Newborn. A Case Report

Introduction

Patent ductus arteriosus involves maintaining the permeability of the vascular ductus located between the pulmonary artery and the descending aorta, due to the failure of transition from foetal to adult type circulation. This malformation is characteristic to premature newborns with extremely low birth weight. The main pathophysiological factors identified in this pathology are immaturity of the smooth muscles, presence of vasodilator mediators and persistent hypoxaemia. Ductal-dependent cardiac malformations require drug therapy for keeping the permeability of the ductus arteriosus until the time of corrective surgery.

Case presentation

We present the case of an extremely low birth weight premature newborn, derived from twin pregnancy with suspected specific pathology, respectively feto-fetal transfusion syndrome, admitted to the Regional Centre of Neonatal Intensive Care Unit Tîrgu-Mureş.Premature newborn with gestational age 31-32 weeks, extremely low birth weight, derived from twin pregnancy, with adequate prenatal follow up, was born by caesarean section for severe intrauterine growth restriction secondary to feto-fetal transfusion syndrome suspicion. The newborn developed respiratory distress syndrome by surfactant deficiency, intraventricular-haemorrhage grade I/II, and severe retinopathy. The detection of a systolic murmur in the second week of life, the diastolic theft revealed by trans-fontanellar ultrasound as well as lowered diastolic blood pressure values raised the suspicion of a patent ductus arteriosus and therefore specific treatment with ibuprofen, a cyclooxygenase inhibitor, was initiated. Progressive alteration of the newborn's condition and the evidence of a coarctation of the aorta imposed the initiation of Prostaglandin E1 therapy and subsequent surgical correction.

Conclusions

Although beneficial, prophylactic or therapeutic closure of persistent ductus arteriosus may worsen the evolution of a newborn with a "silent" cardiac malformation and associated pathology.

The timing of surgical ligation for patent ductus arteriosus is associated with neonatal morbidity in extremely preterm infants born at 23-25 weeks of gestation

The purpose of this study was to evaluate prognostic factors associated with surgical ligation for patent ductus arteriosus (PDA) in extremely preterm infants born at the limits of viability. Ninety infants who were born at 23-25 weeks of gestation and who received surgical ligation were included and their cases were retrospectively reviewed. Infants were classified into two different groups: survivors with no major morbidity (N), and non-survivors or survivors with any major morbidity (M). Clinical characteristics were compared between the groups. Possible prognostic factors were derived from this comparison and further tested by logistic regression analysis. The mean gestational age and the mean birth weight of M were significantly lower than those of N. Notably, the mean postnatal age at time of ligation in N was significantly later than that of the other group (17 ± 12 vs 11 ± 8 days in N and M, respectively). An adjusted analysis showed that delayed ligation (>2 weeks) was uniquely associated with a significantly decreased risk for mortality or composite morbidity after surgical ligation (OR, 0.105; 95% CI, 0.012-0.928). In conclusion, delayed surgical ligation for PDA (>2 weeks) is associated with decreased mortality or morbidities in extremely preterm infants born at 23-25 weeks of gestation.

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.

Comparison of oral paracetamol versus ibuprofen in premature infants with patent ductus arteriosus: a randomized controlled trial

TRIAL DESIGN

Oral ibuprofen has demonstrated good effects on symptomatic patent ductus arteriosus (PDA) but with many contraindications and potential side-effects. In the past two years, oral paracetamol administration to several preterm infants with PDA has been reported. Here, a randomized, non-blinded, parallel-controlled and non-inferiority trial was designed to evaluate the efficacy and safety profiles of oral paracetamol to those of standard ibuprofen for PDA closure in premature infants.

METHODS

One hundred and sixty infants (gestational age ≤ 34 weeks) with echocardiographically confirmed PDA were randomly assigned to receive either oral paracetamol (n = 80) or ibuprofen (n = 80). After the initial treatment course in both groups, the need for a second course was determined by echocardiographic evaluation. The main outcome was rate of ductal closure, and secondary outcomes were adverse effects and complications.

RESULT

The ductus was closed in 65 (81.2%) infants of the paracetamol group compared with 63 (78.8%) of the ibuprofen group. The 95% confidence interval of the difference between these groups was [-0.080,0.128], demonstrating that the effectiveness of paracetamol treatment was not inferior to that of ibuprofen. In fact, the incidence of hyperbilirubinemia or gastrointestinal bleeding in the paracetamol group was significantly lower than that of the ibuprofen group. No significant differences in other clinical side effects or complications were noted.

CONCLUSION

This comparison of drug efficacy and safety profiles in premature infants with PDA revealed that oral paracetamol was comparable to ibuprofen in terms of the rate of ductal closure and even showed a decreased risk of hyperbilirubinemia or gastrointestinal bleeding. Therefore, paracetamol may be accepted as a first-line drug treatment for PDA in preterm infants.

TRIAL REGISTRATION

ChiCTR.org ChiCTR-TRC-12002177.

Management of patent ductus arteriosus in preterm infants--where do we stand?

Patent ductus arteriosus (PDA) in preterm infants is a controversial topic in the management of preterm neonates. There are no generally accepted guidelines for diagnosis, treatment, and follow-up of PDA, and few publications have covered the whole topic or have been conclusively summarized to give a proper direction for the treating physician. Major issues remain to be clarified, both with respect to diagnosis and treatment. The definition of hemodynamic significance varies because of different use of echocardiographic criteria and uncertainty about the role of biomarkers. The detailed risks and benefits of available treatment alternatives are still under investigation. There has been a general shift in the management of PDA in preterm neonates from the "aggressive approach" to a more "conservative approach," but the effects of this strategy on morbidity in a longer time perspective are not fully known. An individualized therapeutic strategy with special emphasis on identification of hemodynamically significance seems to be the way forward. In this review we put forward the scientific background in favor of a seemingly growing body of evidence against active treatment, but we raise caution against shying away from all forms of treatment or instituting them too late. Finally, we try to integrate the current knowledge into suggestions for the management of PDA in premature infants.

Primary surgical closure should be considered in premature neonates with large patent ductus arteriosus

BACKGROUND

Treatment for patent ductus arteriosus (PDA) in premature infants can consist of medical or surgical approaches. The appropriate therapeutic regimen remains contentious. This study evaluated the role of surgery in improving the survival of premature neonates weighing less than 1,500 g with PDA.

MATERIALS AND METHODS

From January 2008 to June 2011, 68 patients weighing less than 1,500 g with PDA were enrolled. The patients were divided into three groups: a group managed only by medical treatment (group I), a group requiring surgery after medical treatment (group II), and a group requiring primary surgical treatment (group III).

RESULTS

The rate of conversion to surgical methods due to failed medical treatment was 67.6% (25/37) in the patients with large PDA (≥2 mm in diameter). The number of patients who could be managed with medical treatment was nine which was only 20.5% (9/44) of the patients with large PDA. There was no surgery-related mortality. Group III displayed a statistically significantly low rate of development of bronchopulmonary dysplasia (BPD) (p=0.008). The mechanical ventilation time was significantly longer in group II (p=0.002).

CONCLUSION

Medical treatment has a high failure rate in infants weighing less than 1,500 g with PDA exceeding 2.0 mm. Surgical closure following medical treatment requires a longer mechanical ventilation time and increases the incidence of BPD. Primary surgical closure of PDA exceeding 2.0 mm in the infants weighing less than 1,500 g should be considered to reduce mortality and long-term morbidity events including BPD.

Therapeutic strategies, including a high surgical ligation rate, for patent ductus arteriosus closure in extremely premature infants in a North American centre

OBJECTIVE

To document the rate of surgical ligation of a patent ductus arteriosus (PDA) in extremely premature infants who had received more than one course of indomethacin. Outcomes were compared among three subgroups (ligation, further indomethacin and no further treatment) of infants who received at least one course of indomethacin, and between two subgroups (one course of indomethacin and more than one course) among infants who underwent ligation.

STUDY DESIGN

A retrospective chart review of all 23 weeks+0 days to 26 weeks+6 days' gestational age infants with a PDA born between 1994 and 2005 was performed. Secondary outcomes were compared among the subgroups.

RESULTS

The final study population consisted of 196 extremely premature infants with a PDA. The rate of surgical ligation in the 88 infants who received more than one course of indomethacin was 64%. The ligation subgroup, in comparison with the no further treatment subgroup, spent a greater median time on mechanical ventilation (39 versus 29 days, P<0.001) and in hospital (115 versus 92 days P=0.002), while trending toward lower mortality (18% versus 40%, P=0.07). The PDA closed following the first course of indomethacin in only 20% of infants.

CONCLUSIONS

A majority of extremely premature infants receiving more than one course of indomethacin underwent surgical ligation. Repeated indomethacin courses were generally well tolerated, but were mostly unsuccessful. Ligation appears to have potential risks and benefits. A randomized trial should be performed after studies define a hemodynamically significant PDA that will result in morbidity and/or mortality unless treated.

Surgical versus medical treatment with cyclooxygenase inhibitors for symptomatic patent ductus arteriosus in preterm infants

BACKGROUND

A patent ductus arteriosus (PDA) with significant left to right shunt increases morbidity and mortality in preterm infants. Early closure of the ductus arteriosus may be achieved pharmacologically or by surgery. The preferred initial treatment of a symptomatic PDA, surgical ligation or treatment with indomethacin, is not clear.

OBJECTIVES

To compare the effect of surgical ligation of PDA versus medical treatment with cyclooxygenase inhibitors (indomethacin, ibuprofen or mefenamic acid), each used as the initial treatment, on neonatal mortality in preterm infants with a symptomatic PDA.

SEARCH METHODS

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

SELECTION CRITERIA

Randomised or quasi-randomised trials in preterm or low birth weight neonates with symptomatic PDA and comparing surgical ligation with medical treatment with cyclooxygenase inhibitors, each used as the initial treatment for closure of PDA.

DATA COLLECTION AND ANALYSIS

The authors independently assessed methodological quality and extracted data for the included trial. We used RevMan 5.1 for analyses of the data.

MAIN RESULTS

One study reporting on 154 neonates was found eligible. No significant difference between surgical closure and indomethacin treatment was found for in-hospital mortality, chronic lung disease, necrotising enterocolitis, sepsis, creatinine level or intraventricular haemorrhage. There was a significant increase in the surgical group in the incidence of pneumothorax (risk ratio (RR) 2.68; 95% confidence interval (CI) 1.45 to 4.93; risk difference (RD) 0.25; 95% CI 0.11 to 0.38; number needed to treat to harm (NNTH) 4 (95% CI 3 to 9)) and retinopathy of prematurity stage III and IV (RR 3.80; 95% CI 1.12 to 12.93; RD 0.11; 95% CI 0.02 to 0.20; NNTH 9 (95% CI 5 to 50)) compared to the indomethacin group. There was a statistically significant decrease in failure of ductal closure rate in the surgical group as compared to the indomethacin group (RR 0.04; 95% CI 0.01 to 0.27; RD -0.32; 95% CI -0.43 to -0.21, number needed to treat to benefit (NNTB) 3 (95% CI 2 to 4)). No new trials were identified for inclusion in the 2012 update.

AUTHORS' CONCLUSIONS

There are insufficient data to conclude whether surgical ligation or medical treatment with indomethacin is preferred as the initial treatment for symptomatic PDA in preterm infants.

Vocal cord paralysis post patent ductus arteriosus ligation surgery: risks and co-morbidities

OBJECTIVES

1. To determine the prevalence of left vocal cord paralysis (LVCP) post patent ductus arteriosus (PDA) ligation at a Tertiary Care Centre. 2. To identify risk factors associated with LVCP. 3. To identify co-morbidities associated with LVCP. 4. To determine the frequency of pre- and post-operative nasopharyngolaryngoscopic (NPL) examination in this patient population.

METHODS

Retrospective chart review of all infants who underwent PDA ligation surgery at a tertiary care academic hospital between July 2003 and July 2010. Data on patient age, gender, weight, method of PDA ligation, and results of NPL scoping were collected, as well as patient co-morbidities post PDA ligation.

RESULTS

One hundred and fifteen patients underwent PDA ligation surgery. Four patients were excluded due to bilateral vocal cord paralysis. Of the remaining 111 patients, nineteen patients (17.1%) were found to have LVCP. Low birth weight was identified as a significant risk factor for LVCP (p=0.002). Gastroesophageal reflux was identified as a significant co-morbidity associated with LVCP post PDA ligation (p=0.002). Only 0.9% of patients were scoped pre-operatively, and 27.9% were scoped postoperatively.

CONCLUSIONS

LVCP is associated with multiple morbidities. The authors strongly recommend routine post-operative scoping of all patients post PDA ligation surgery, and preoperative scoping when possible. A prospective study is warranted, in order to confirm the prevalence of LVCP as well as risk factors and associated co-morbidities.

Managing the patent ductus arteriosus in the premature neonate: a new look at what we thought we knew

Over recent years, the clinical approach to patency of the ductus arteriosus in the premature neonate has been the subject of intensive reevaluation. What had once been considered inherently obvious is no longer to be taken for granted. In this review we will focus on some of the controversies surrounding various aspects of the pharmacologic treatment regimens for patent ductus arteriosus closure. The pros and cons of prophylactic vs therapeutic indomethacin, of early vs late therapy, of high- vs low-dose indomethacin, of single vs multiple courses of treatment, and of ibuprofen vs indomethacin will be considered. In addition, the possibility that patency of the ductus arteriosus is merely a physiological manifestation of extreme prematurity, and thus does not necessarily need to be therapeutically closed, has become a viable approach in some cases. As such, we will examine echocardiographic and biochemical criteria aimed at determining the clinical and hemodynamic significance of ductal shunting, and thereby of the need to treat. Finally, we speculate on potential therapeutic directions for the future, including individualized treatment regimens and multidrug treatment cocktails for those who fail initial monodrug therapy.

Improved closure of patent ductus arteriosus with high doses of ibuprofen

The patent ductus arteriosus (PDA) is associated with various complications of prematurity. Cyclooxygenase-inhibitors are the first-line intervention for closure of the PDA. However, the rates of PDA closure still are unsatisfactory. Therefore, an individual trial was performed by changing the strategy for treating neonates with ibuprofen to induce the closure of PDA. In a retrospective study, patients receiving 20, 10, and 10 mg/kg bodyweight ibuprofen (group 1) were compared by chart review with those receiving 10, 5, 5 mg/kg (group 2). The rate of PDA closure, the incidence of side effects related to the use of ibuprofen, and the need for surgical intervention for closure of the PDA were analyzed. A higher rate of closure after three doses in group 1 could be observed (60.9 vs 52.6%; p = 0.75), which was not significant but indicated a clear positive trend. If closure of the PDA was unsuccessful, intravenous ibuprofen was continued for an additional 2 days. After 5 days, 91.3% of PDA in group 1 was closed compared with 68.4% PDA in group 2. In summary, only 8.7% of the group 1 neonates needed surgical closure of PDA after insufficient medicamentous closure compared with 31.6% in group 2 (p = 0.25). Although not statistically significant, a clear positive trend for using the higher-dose medication can be seen. More work dealing with the limitations of a retrospective study must be done. Based on the data from this study, high-dose ibuprofen seems able to increase the rate of effective medicamentous PDA closure without any further unwanted side effects.

Role of prophylactic surgical ligation of patent ductus arteriosus in extremely low birth weight infants: Systematic review and implications for clinical practice

Objectives:

To investigate the effectiveness and safety of prophylactic surgical ligation of patent ductus arteriosus (PDA) on mortality and morbidity of preterm infants weighing less than 1000 g at birth.

Materials and Methods:

The study conducted a systematic search of available database from 1996-2008. Retrieved articles were assessed for eligibility and data was abstracted independently by two reviewers. Decisions to include studies for review and the methodological quality of included studies were asssessed in duplicate based on predetermined criteria. No language restrictions were applied.

Results:

Only one eligible study that enrolled 84 extremely low birth weight infants was identified. Prophylactic surgical ligation of PDA resulted in a statistically significant reduction of severe stage II or III necrotizing enterocolitis, [RR 0.25, 95% CI (0.08, 0.83), P value 0.02, number needed to treat 5]. The study, however, found no statistically significant difference in mortality, intraventricular hemorrhage, bronchopulmonary dysplasia, and retinopathy of prematurity.

Conclusions:

Current evidence does not support the use of prophylactic surgical ligation of PDA in the management of the preterm infants.

Patent ductus arteriosus in the preterm infant: a survey of clinical practices in French neonatal intensive care units

Patent ductus arteriosus (PDA) is one of the most common problems in the care of premature infants, especially the extremely premature. There is no real consensus regarding the diagnostic criteria or treatment of a hemodynamically significant PDA. Its diagnosis, assessment, and treatment still remain challenges. Therefore, we investigated clinical practices in French tertiary neonatology centers regarding the management of PDA to compare their similarities and differences. We sent a questionnaire by email to the PDA specialist in every French tertiary neonatal intensive care unit. It contained 27 items regarding the unit's structure, method of diagnosing PDA, and treatment choices. The completed questionnaire were returned via email and analyzed blindly. The questionnaire response rate was 87.5%, which allowed us to draw some conclusions regarding French clinical practices in the care of neonates with PDA. Although the diagnostic criteria are quite similar, the therapeutic practices are rather different across neonatal care units. We highlight the great variability in French clinical practices when it comes to treating PDA and underscore the necessity for harmonization of these practices, which could be achieved using multicenter, randomized studies to identify the advantages of one approach compared with another.

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.

Commonly encountered surgical problems in the fetus and neonate

Neonatal surgical care requires a current understanding of pre- and postnatal intervention for a myriad of congenital anomalies. This article includes an update of the recent information on commonly encountered fetal and neonatal surgical problems, highlighting specific areas of controversy and challenges in diagnosis. The authors hope that this article is useful for trainees and practitioners involved in any aspect of fetal and neonatal care.

Therapeutic management of patent ductus arteriosus

Management of patent ductus arteriosus (PDA) in premature neonates has always been a challenge to the neonatologist and continues to be a controversial topic. Indications for treatment are not clear. Approximately 40% of ductus arteriosus close spontaneously even in extremely-low-birth-weight neonates. Prophylactic or early pre-symptomatic treatment may unnecessarily expose these babies, in whom the ductus might close spontaneously, to pharmacologic agents and their adverse effects. On the other hand, with advancing postnatal age, delaying treatment could potentially decrease successful medical closure thereby increasing the rate of surgical ligation and the complications associated with surgery. We tried to develop some clinical guidelines for management of PDA in premature neonates based on evidence, or lack thereof, and experience.

Prophylactic surgical ligation of patent ductus arteriosus for prevention of mortality and morbidity in extremely low birth weight infants

BACKGROUND

Patent ductus arteriosus (PDA) is associated with increased mortality and morbidity in preterm infants. Prophylactic indomethacin results in favorable intermediate outcomes such as reduction of significant PDA, need for surgical ligation, severe intraventricular hemorrhage and serious pulmonary hemorrhage without modifying long-term neurosensory outcomes. Little is known about the effectiveness and safety of prophylactic surgical closure of the PDA in extremely low birth weight (ELBW) infants.

OBJECTIVES

To identify and summarize evidence from randomized controlled trials investigating the effectiveness and safety of prophylactic surgical ligation of the PDA on mortality and morbidities of preterm infants less than 1000 g at birth as compared to no prophylaxis or prophylactic cyclooxygenase inhibitors.

SEARCH STRATEGY

The standard search strategy for the Cochrane Neonatal Review Group was performed by two review authors. Searches were made of MEDLINE (1966 to December 2006), EMBASE (1980 to December 2006), the Cochrane Central Register of Controlled Trials (The Cochrane Library, Issue 4, 2006), and abstracts of annual meetings of the Society for Pediatric Research (1995 - 2006). Contacts were made with the authors of published articles.

SELECTION CRITERIA

Randomized or quazi-randomized controlled trials that enrolled infants less than 28 weeks gestation or less than 1000 g at birth who are on assisted ventilation and/or supplemental oxygen without clinical signs of hemodynamic significance of the ductus arteriosus were considered. Trials addressing prophylactic surgical ligation of the patent ducts arteriosus (i.e. procedure done during the first 72 hours of life) versus no intervention or cyclooxygenase inhibitor prophylaxis were included. The primary outcome was bronchopulmonary dysplasia (BPD). Other important short and long-term neonatal outcomes were also considered.

DATA COLLECTION AND ANALYSIS

Standard methods of the Cochrane Collaboration and its Neonatal Review Group were used to assess the methodologic quality of the trials. Retrieved articles were assessed for eligibility and data was abstracted independently by two reviewer authors. Where data were incomplete, the primary investigators were contacted for further information and clarifications. For dichotomous outcomes, relative risk (RR) and its associated confidence interval were calculated. For continuous outcomes, treatment effect was expressed as mean difference and its calculated standard deviation. When appropriate, meta-analysis of pooled data was performed assuming a fixed effect model

MAIN RESULTS

Only one eligible study that enrolled 84 ELBW infants was identified. The prophylactic group had ductal ligation performed within 24 hours of life following a pre-specified protocol, while the control group received standard care without indomethacin. Prophylactic surgical ligation of the PDA resulted in a statistically significant reduction of severe stage II or III necrotizing enterocolitis (NEC), [RR 0.25, 95% CI (0.08,0.83), p value 0.02, NNT 5]. The study found no statistically significant difference in mortality, severe grade III and IV intraventricular hemorrhage (IVH), BPD, and retinopathy of prematurity (ROP). Of note, the study was unblinded and underpowered to detect clinically important differences in the above mentioned outcomes.

AUTHORS' CONCLUSIONS

Prophylactic surgical ligation of the PDA did not decrease mortality or BPD in ELBW infants. A significant reduction of stage II or III NEC was noted. Based on the current evidence, the high rate of spontaneous closure, availability of effective safe medical therapies, and the potential short and long-term complications of surgical ligation, the use such prophylactic surgical therapy is not indicated in the management of the preterm infants.

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.