Comparative evaluation of the effects of indomethacin and ibuprofen on cerebral perfusion and oxygenation in preterm infants with patent ductus arteriosus

Interventions for patent ductus arteriosus (PDA) in preterm infants: an overview of Cochrane Systematic Reviews

BACKGROUND

Patent ductus arteriosus (PDA) is associated with significant morbidity and mortality in preterm infants. Several non-pharmacological, pharmacological, and surgical approaches have been explored to prevent or treat a PDA.

OBJECTIVES

To summarise Cochrane Neonatal evidence on interventions (pharmacological or surgical) for the prevention of PDA and related complications, and interventions for the management of asymptomatic and symptomatic PDA in preterm infants.

METHODS

We searched the Cochrane Database of Systematic Reviews on 20 October 2022 for ongoing and published Cochrane Reviews on the prevention and treatment of PDA in preterm (< 37 weeks' gestation) or low birthweight (< 2500 g) infants. We included all published Cochrane Reviews assessing the following categories of interventions: pharmacological therapy using prostaglandin inhibitor drugs (indomethacin, ibuprofen, and acetaminophen), adjunctive pharmacological interventions, invasive PDA closure procedures, and non-pharmacological interventions. Two overview authors independently checked the eligibility of the reviews retrieved by the search, and extracted data from the included reviews using a predefined data extraction form. Any disagreements were resolved by discussion with a third overview author. Two overview authors independently assessed the methodological quality of the included reviews using the AMSTAR 2 (A MeaSurement Tool to Assess systematic Reviews) tool. We reported the GRADE certainty of evidence as assessed by the respective review authors using summary of findings tables.

MAIN RESULTS

We included 16 Cochrane Reviews, corresponding to 138 randomised clinical trials (RCT) and 11,856 preterm infants, on the prevention and treatment of PDA in preterm infants. One of the 16 reviews had no included studies, and therefore, did not contribute to the results. Six reviews reported on prophylactic interventions for the prevention of PDA and included pharmacological prophylaxis with prostaglandin inhibitor drugs, prophylactic surgical PDA ligation, and non-pharmacologic interventions (chest shielding during phototherapy and restriction of fluid intake); one review reported on the use of indomethacin for the management of asymptomatic PDA; nine reviews reported on interventions for the management of symptomatic PDA, and included pharmacotherapy with prostaglandin inhibitor drugs in various routes and dosages, surgical PDA ligation, and adjunct therapies (use of furosemide and dopamine in conjunction with indomethacin). The quality of reviews varied. Two reviews were assessed to be high quality, seven reviews were of moderate quality, five of low quality, while two reviews were deemed to be of critically low quality. For prevention of PDA, prophylactic indomethacin reduces severe intraventricular haemorrhage (IVH; relative risk (RR) 0.66, 95% confidence interval (CI) 0.53 to 0.82; 14 RCTs, 2588 infants), and the need for invasive PDA closure (RR 0.51, 95% CI 0.37 to 0.71; 8 RCTs, 1791 infants), but it does not appear to affect the composite outcome of death or moderate/severe neurodevelopmental disability (RR 1.02, 95% CI 0.90 to 1.15; 3 RCTs, 1491 infants). Prophylactic ibuprofen probably marginally reduces severe IVH (RR 0.67, 95% CI 0.45 to 1.00; 7 RCTs, 925 infants; moderate-certainty evidence), and the need for invasive PDA closure (RR 0.46, 95% CI 0.22 to 0.96; 7 RCTs, 925 infants; moderate-certainty evidence). The evidence is very uncertain on the effect of prophylactic acetaminophen on severe IVH (RR 1.09, 95% CI 0.07 to 16.39; 1 RCT, 48 infants). Necrotising enterocolitis (NEC) was lower with both prophylactic surgical ligation (RR 0.25, 95% CI 0.08 to 0.83; 1 RCT, 84 infants), and fluid restriction (RR 0.43, 95% CI 0.21 to 0.87; 4 RCTs, 526 infants). For treatment of asymptomatic PDA, indomethacin appears to reduce the development of symptomatic PDA post-treatment (RR 0.36, 95% CI 0.19 to 0.68; 3 RCTs, 97 infants; quality of source review: critically low). For treatment of symptomatic PDA, all available prostaglandin inhibitor drugs appear to be more effective in closing a PDA than placebo or no treatment (indomethacin: RR 0.30, 95% CI 0.23 to 0.38; 10 RCTs, 654 infants; high-certainty evidence; ibuprofen: RR 0.62, 95% CI 0.44 to 0.86; 2 RCTs, 206 infants; moderate-certainty evidence; early administration of acetaminophen: RR 0.35, 95% CI 0.23 to 0.53; 2 RCTs, 127 infants; low-certainty evidence). Oral ibuprofen appears to be more effective in PDA closure than intravenous (IV) ibuprofen (RR 0.38, 95% CI 0.26 to 0.56; 5 RCTs, 406 infants; moderate-certainty evidence). High-dose ibuprofen appears to be more effective in PDA closure than standard-dose ibuprofen (RR 0.37, 95% CI 0.22 to 0.61; 3 RCTs, 190 infants; moderate-certainty evidence). With respect to adverse outcomes, compared to indomethacin administration, NEC appears to be lower with ibuprofen (any route; RR 0.68, 95% CI 0.49 to 0.94; 18 RCTs, 1292 infants; moderate-certainty evidence), oral ibuprofen (RR 0.41, 95% CI 0.23 to 0.73; 7 RCTs, 249 infants; low-certainty evidence), and with acetaminophen (RR 0.42, 95% CI 0.19 to 0.96; 4 RCTs, 384 infants; low-certainty evidence). However, NEC appears to be increased with a prolonged course of indomethacin versus a shorter course (RR 1.87, 95% CI 1.07 to 3.27; 4 RCTs, 310 infants).

AUTHORS' CONCLUSIONS

This overview summarised the evidence from 16 Cochrane Reviews of RCTs regarding the effects of interventions for the prevention and treatment of PDA in preterm infants. Prophylactic indomethacin reduces severe IVH, but does not appear to affect the composite outcome of death or moderate/severe neurodevelopmental disability. Prophylactic ibuprofen probably marginally reduces severe IVH (moderate-certainty evidence), while the evidence is very uncertain on the effect of prophylactic acetaminophen on severe IVH. All available prostaglandin inhibitor drugs appear to be effective in symptomatic PDA closure compared to no treatment (high-certainty evidence for indomethacin; moderate-certainty evidence for ibuprofen; low-certainty evidence for early administration of acetaminophen). Oral ibuprofen appears to be more effective in PDA closure than IV ibuprofen (moderate-certainty evidence). High dose ibuprofen appears to be more effective in PDA closure than standard-dose ibuprofen (moderate-certainty evidence). There are currently two ongoing reviews, one on fluid restriction for symptomatic PDA, and the other on invasive management of PDA in preterm infants.

Differential effects of ibuprofen and indomethacin on cerebral oxygen kinetics in the very preterm baby

BACKGROUND

Ibuprofen is preferred to indomethacin for treatment of a significant patent ductus arteriosus (PDA) in preterm babies despite indomethacin being associated with a lower risk of intraventricular haemorrhage. This difference is thought to relate to the discrepant effects of each medication on cerebral oxygen kinetics yet the effect of ibuprofen on cerebral perfusion is uncertain.

METHODS

Forty-eight babies < 30 weeks with a significant PDA, defined by echocardiography, were randomly assigned to either indomethacin or ibuprofen (n = 24 per group) and stratified by gestation and chronologic age. Cerebral blood flow [total internal carotid blood flow (TICF)] and oxygen physiology [oxygen delivery (modCerbDO₂) and consumption (modCerbVO₂)] were measured using cranial Doppler ultrasound and near-infrared spectroscopy, and cerebral oxygen extraction (cFTOE) calculated, immediately before and following administration. Temporal and treatment related changes were analysed.

RESULTS

A fixed effect of time was seen for TICF (p = 0.03) and therefore modCerbDO₂ (p = 0.046) and cFTOE (p = 0.04) for indomethacin alone. In the indomethacin group, TICF and modCerbDO₂ fell from baseline to 5 and 30 min respectively (TICF p < 0.01, cDO₂ p = 0.01) before increasing from 5 min to 24 h (p < 0.01) and 30 min and 24 h (p < 0.01) timepoints. cFTOE peaked at 30 min (p = 0.02) returning to baseline at 24 h. There was a parallel increase in arterial lactate.

CONCLUSION

Indomethacin significantly reduces cerebral blood flow soon after administration, resulting in a parallel increase in oxygen extraction and arterial lactate. This implies that the balance of oxygen kinetics at the time of treatment may be critical in very preterm babies with significant PDA.

Comparison of Gastrointestinal Complications of Paracetamol and Ibuprofen in the Management of Infants with Patent Ductus Arteriosus: A Randomized Clinical Trial Study

Background:

Patent ductus arteriosus (PDA) is one of the more common congenital heart defects in preterm neonates. The closure of PDA can be done with ibuprofen; however, this drug is associated with many contraindications and potential side-effects. In the past years, paracetamol has been proposed for the treatment of PDA. This study was designed to evaluate the efficacy and gastrointestinal complications of paracetamol and ibuprofen for the pharmacological closure of PDA in preterm infants.

Methods:

In a clinical trial study, 40 preterm infants with echocardiographically confirmed PDA were randomly assigned to receive either paracetamol (n = 23; 15 mg/kg every 6 h for 2 days) or ibuprofen (n = 17; initial dose of 10 mg/kg, followed by 5 mg/kg every 12 h for 2 days). The neonates matched for gestational age and weight. We used t-test for parametric, Chi-square for categorial, and Wilcoxson for nonparametric variables. Significant level was considered less than 0.05.

Results:

Platelet count, BUN and creatinine levels, and closure of PDA had not significant difference between two groups (P > 0.05). Incidence and severity of GI bleeding, feeding intolerance, and NEC were significantly more in infants who received paracetamol than ibuprofen (P < 0.05).

Conclusions:

There were no differences in the rate of PDA closure between the two drugs, but with respect to complications, rate and severity of GI bleeding, feeding intolerance, and NEC were significantly more in infants who received paracetamol than ibuprofen. Therefore, paracetamol could not be used as a proper alternative agent for ibuprofen in the treatment of PDA in preterm infants.

Simulating the effect of cerebral blood flow changes on regional quantification of [18F]flutemetamol and [18F]florbetaben studies

Global and regional changes in cerebral blood flow (CBF) can result in biased quantitative estimates of amyloid load by PET imaging. Therefore, the current simulation study assessed effects of these changes on amyloid quantification using a reference tissue approach for [¹⁸F]flutemetamol and [¹⁸F]florbetaben. Previously validated pharmacokinetic rate constants were used to simulate time-activity curves (TACs) corresponding to full dynamic and dual-time-window acquisition protocols. CBF changes were simulated by varying the tracer delivery (K₁) from +25 to -25%. The standardized uptake value ratio (SUVr) was computed and TACs were fitted using reference Logan (RLogan) and the simplified reference tissue model (SRTM) to obtain the relative delivery rate (R₁) and volume of distribution ratio (DVR). RLogan was least affected by CBF changes (χ² = 583 p < 0.001, χ² = 81 p < 0.001, for [¹⁸F]flutemetamol and [¹⁸F]florbetaben, respectively) and the extent of CBF sensitivity generally increased for higher levels of amyloid. Further, SRTM-derived R₁ changes correlated well with simulated CBF changes (R² > 0.95) and SUVr's sensitivity to CBF changes improved for later uptake-times, with the exception of [¹⁸F]flutemetamol cortical changes. In conclusion, RLogan is the preferred method for amyloid quantification of [¹⁸F]flutemetamol and [¹⁸F]florbetaben studies and SRTM could be additionally used for obtaining a CBF proxy.

Ibuprofen for the treatment of patent ductus arteriosus in preterm or low birth weight (or both) infants

BACKGROUND

Indomethacin is used as standard therapy to close a patent ductus arteriosus (PDA) but is associated with reduced blood flow to several organs. Ibuprofen, another cyclo-oxygenase inhibitor, may be as effective as indomethacin with fewer adverse effects.

OBJECTIVES

To determine the effectiveness and safety of ibuprofen compared with indomethacin, other cyclo-oxygenase inhibitor(s), placebo, or no intervention for closing a patent ductus arteriosus in preterm, low-birth-weight, or preterm and low-birth-weight infants.

SEARCH METHODS

We used the standard search strategy of Cochrane Neonatal to search the Cochrane Central Register of Controlled Trials (CENTRAL 2017, Issue 10), MEDLINE via PubMed (1966 to 30 November 2017), Embase (1980 to 30 November 2017), and CINAHL (1982 to 30 November 2017). 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 or quasi-randomised controlled trials of ibuprofen for the treatment of a PDA in preterm, low birth weight, or both preterm and low-birth-weight newborn infants.

DATA COLLECTION AND ANALYSIS

Data collection and analysis conformed to the methods of the Cochrane Neonatal Review Group. We used the GRADE approach to assess the quality of evidence.

MAIN RESULTS

We included 39 studies enrolling 2843 infants. Ibuprofen (IV) versus placebo: IV Ibuprofen (3 doses) reduced the failure to close a PDA compared with placebo (typical relative risk (RR); 0.62 (95% CI 0.44 to 0.86); typical risk difference (RD); -0.18 (95% CI -0.30 to -0.06); NNTB 6 (95% CI 3 to 17); I² = 65% for RR and I² = 0% for RD; 2 studies, 206 infants; moderate-quality the evidence). One study reported decreased failure to close a PDA after single or three doses of oral ibuprofen compared with placebo (64 infants; RR 0.26, 95% CI 0.11 to 0.62; RD -0.44, 95% CI -0.65 to -0.23; NNTB 2, 95% CI 2 to 4; I² test not applicable). Ibuprofen (IV or oral) compared with indomethacin (IV or oral): Twenty-four studies (1590 infants) comparing ibuprofen (IV or oral) with indomethacin (IV or oral) found no significant differences in failure rates for PDA closure (typical RR 1.07, 95% CI 0.92 to 1.24; typical RD 0.02, 95% CI -0.02 to 0.06; I² = 0% for both RR and RD; moderate-quality evidence). A reduction in NEC (necrotising enterocolitis) was noted in the ibuprofen (IV or oral) group (18 studies, 1292 infants; typical RR 0.68, 95% CI 0.49 to 0.94; typical RD -0.04, 95% CI -0.07 to -0.01; NNTB 25, 95% CI 14 to 100; I² = 0% for both RR and RD; moderate-quality evidence). There was a statistically significant reduction in the proportion of infants with oliguria in the ibuprofen group (6 studies, 576 infants; typical RR 0.28, 95% CI 0.14 to 0.54; typical RD -0.09, 95% CI -0.14 to -0.05; NNTB 11, 95% CI 7 to 20; I² = 24% for RR and I² = 69% for RD; moderate-quality evidence). The serum/plasma creatinine levels 72 hours after initiation of treatment were statistically significantly lower in the ibuprofen group (11 studies, 918 infants; MD -8.12 µmol/L, 95% CI -10.81 to -5.43). For this comparison, there was high between-study heterogeneity (I² = 83%) and low-quality evidence. Ibuprofen (oral) compared with indomethacin (IV or oral): Eight studies (272 infants) reported on failure rates for PDA closure in a subgroup of the above studies comparing oral ibuprofen with indomethacin (IV or oral). There was no significant difference between the groups (typical RR 0.96, 95% CI 0.73 to 1.27; typical RD -0.01, 95% CI -0.12 to 0.09; I² = 0% for both RR and RD). The risk of NEC was reduced with oral ibuprofen compared with indomethacin (IV or oral) (7 studies, 249 infants; typical RR 0.41, 95% CI 0.23 to 0.73; typical RD -0.13, 95% CI -0.22 to -0.05; NNTB 8, 95% CI 5 to 20; I² = 0% for both RR and RD). There was low-quality evidence for these two outcomes. There was a decreased risk of failure to close a PDA with oral ibuprofen compared with IV ibuprofen (5 studies, 406 infants; typical RR 0.38, 95% CI 0.26 to 0.56; typical RD -0.22, 95% CI -0.31 to -0.14; NNTB 5, 95% CI 3 to 7; moderate-quality evidence). There was a decreased risk of failure to close a PDA with high-dose versus standard-dose of IV ibuprofen (3 studies 190 infants; typical RR 0.37, 95% CI 0.22 to 0.61; typical RD - 0.26, 95% CI -0.38 to -0.15; NNTB 4, 95% CI 3 to 7); I² = 4% for RR and 0% for RD); moderate-quality evidence). Early versus expectant administration of IV ibuprofen, echocardiographically-guided IV ibuprofen treatment versus standard IV ibuprofen treatment, continuous infusion of ibuprofen versus intermittent boluses of ibuprofen, and rectal ibuprofen versus oral ibuprofen were studied in too few trials to allow for precise estimates of any clinical outcomes.

AUTHORS' CONCLUSIONS

Ibuprofen is as effective as indomethacin in closing a PDA. Ibuprofen reduces the risk of NEC and transient renal insufficiency. Therefore, of these two drugs, ibuprofen appears to be the drug of choice. The effectiveness of ibuprofen versus paracetamol is assessed in a separate review. Oro-gastric administration of ibuprofen appears as effective as IV administration. To make further recommendations, studies are needed to assess the effectiveness of high-dose versus standard-dose ibuprofen, early versus expectant administration of ibuprofen, echocardiographically-guided versus standard IV ibuprofen, and continuous infusion versus intermittent boluses of ibuprofen. Studies are lacking evaluating the effect of ibuprofen on longer-term outcomes in infants with PDA.

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.

Cerebral Hemodynamics Are Not Affected by the Size of the Patent Ductus Arteriosus

INTRODUCTION

Although patent ductus arteriosus (PDA) has been implicated to play a role in the development of cerebral ischemia and intraventricular hemorrhage (IVH) through a cerebral steal phenomenon, there is conflicting data on the impact of PDA size on cerebral blood flow (CBF). Cerebral autoregulation is the brain's innate protective mechanism to maintain constant CBF despite changes in blood pressure, and it is unclear if it is influenced by PDA hemodynamics.

OBJECTIVE

To delineate the relationship between PDA size and CBF velocity (CBFv) in premature infants.

METHODS

113 premature infants born at 23-29 weeks' gestation had echocardiograms performed during the first week after birth to evaluate for PDA. The infants were divided into 3 groups according to PDA size: none-to-small, moderate, or large. All infants had continuous recordings of umbilical artery blood pressure (ABP) and CBFv during the first week after birth. Critical closing pressure (CrCP) was calculated from ABP and CBFv tracings. Diastolic closing margin (DCM), defined as diastolic blood pressure minus CrCP, was calculated as a marker for the risk of developing IVH.

RESULTS

Infants with a large PDA (n = 16) had the lowest ABP across all phases of the cardiac cycle (systole [p = 0.003], mean [p = 0.005], and diastole [p = 0.012]) compared to infants with a moderate (n = 19) or none-to-small PDA (n = 78). Despite blood pressure being different, systolic, mean, and diastolic CBFv were not different across groups. Cerebral autoregulation, as measured during systole, was intact regardless of the PDA size. CrCP and DCM were also not different across groups.

CONCLUSIONS

In this cohort, CBFv and cerebral autoregulation during systole were not influenced by PDA size. Intact cerebral autoregulation may play a role in maintaining CBFv regardless of PDA size and differences in ABP.

Efficacy and safety of pharmacological treatments for patent ductus arteriosus closure: A systematic review and network meta-analysis of clinical trials and observational studies

Efficacy and safety profiles of different pharmacological interventions used to treat patent ductus arteriosus (PDA) are relatively unexplored. Integrating the findings of randomized clinical trials (RCTs) with those from observational studies may provide key evidence on this important issue. We aimed at estimating the relative likelihood of failure to close the PDA, need for surgical closure, and occurrence of adverse events among preterm and full-term infants treated with indomethacin, ibuprofen, or acetaminophen, placebo, or no treatment including both RCTs and observational studies. We searched PubMed, Embase, and the Register of Controlled Trials from inception to October 30, 2018. We first estimated proportions of subjects with failure to close the PDA, subjects in whom surgical closure was performed after pharmacological treatment, death, and subjects with selected adverse events (AEs). These estimates were obtained using frequentist random-effect meta-analysis of arm-specific proportions. We then compared active drugs with each other and with control (either placebo or no treatment) by summarizing results at the end of treatment reported in the papers, regardless of number of administration(s), dose, route and type of administration, and study design and quality. We also summarized primary outcome results separately at first, second and third cycles of treatment. These estimates were obtained using Bayesian random-effects network meta-analysis for mixed comparisons, and frequentist random-effect pairwise meta-analysis for direct comparisons. We included 64 RCTs and 24 observational studies including 14,568 subjects (5339 in RCTs and 9229 in observational studies, 8292 subjects received indomethacin, 4761 ibuprofen, 574 acetaminophen, and 941 control (including placebo or no intervention).The proportion of subjects with failure to close the PDA was 0.24 (95% Confidence Interval, CI: 0.20, 0.29) for indomethacin, 0.18 (0.14, 0.22) for ibuprofen, 0.19 (0.09, 0.30) for acetaminophen, and 0.59 (0.48, 0.69) for control. At end of treatment, compared to control, we found inverse associations between all active drugs and failure to close PDA (for indomethacin Odds Ratio, OR, was 0.17 [95% Credible Interval, CrI: 0.11-0.24], ibuprofen 0.19 [0.12-0.28], and acetaminophen 0.15 [0.09-0.26]), without differences among active drugs. We showed inverse associations between effective drugs and need for surgical closure, as compared to control (for indomethacin OR was 0.28 [0.15-0.50], ibuprofen 0.30 [0.16-0.54], and acetaminophen 0.19 [0.07-0.46]), without differences among drugs. Indomethacin was directly associated with intraventricular hemorrhage (IVH) (1.27; 1.00, 1.62) compared to ibuprofen, and to oliguria as compared to ibuprofen (3.92; 1.69, 9.82) or acetaminophen (10.8; 1.86, 93.1). In conclusion, active pharmacological treatment, with indomethacin, ibuprofen, or acetaminophen, is inversely associated with failure to close the PDA compared to non-treatment. Ibuprofen should be preferred to indomethacin to avoid occurrence of IVH or oliguria, acetaminophen should be preferred to indomethacin to avoid oliguria.

Patent ductus arteriosus ligation on neurodevelopmental outcomes at corrected 2 years

Background

Our aim in this study was to evaluate whether very low birth weight infants (VLBWI) ligated for patent ductus arteriosus (PDA) were associated with worse neurodevelopmental outcomes at corrected 2 years. The ligated group was subdivided into ≤2 weeks of life (early) and ligated > 2 weeks of life (late) groups and compared the in-hospital morbidities and long term outcomes.

Methods

Between Dec 2013 and Dec 2015, VLBWI diagnosed with hs PDA were evaluated.

Results

Of the 191 VLBW infants with hs PDA, 28 (14.7%) infants had surgical ligation for PDA; 11 (39%) infants had EL and 17 (61%) infants had LL. Surgical ligation of hs PDA group had higher morbidities and mortality. Among the142 (83.0%) infants of 171 VLBWI with PDA survived, infants who were ligated had significantly lower scores of Bayley Scales of Infant and Toddler Development III at corrected age of 18 months. However, among the ligated group, there was little evidence of differences between the EL and LL groups. In a multivariable logistic regression analysis, only longer exposure of hs PDA and mechanical ventilation were consistently associated with worse neurodevelopmental outcomes.

Conclusion

Our results suggest that surgical ligation for hs PDA may not increase risk for poor neurodevelopmental outcomes at corrected 2 years of age. The early surgical ligation may not be a risk factor.

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.

Ibuprofen for the treatment of patent ductus arteriosus in preterm or low birth weight (or both) infants

BACKGROUND

Indomethacin is used as standard therapy to close a patent ductus arteriosus (PDA) but is associated with reduced blood flow to several organs. Ibuprofen, another cyclo-oxygenase inhibitor, may be as effective as indomethacin with fewer adverse effects.

OBJECTIVES

To determine the effectiveness and safety of ibuprofen compared with indomethacin, other cyclo-oxygenase inhibitor(s), placebo, or no intervention for closing a patent ductus arteriosus in preterm, low-birth-weight, or preterm and low-birth-weight infants.

SEARCH METHODS

We used the standard search strategy of Cochrane Neonatal to search the Cochrane Central Register of Controlled Trials (CENTRAL 2017, Issue 10), MEDLINE via PubMed (1966 to 30 November 2017), Embase (1980 to 30 November 2017), and CINAHL (1982 to 30 November 2017). 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 or quasi-randomised controlled trials of ibuprofen for the treatment of a PDA in preterm, low birth weight, or both preterm and low-birth-weight newborn infants.

DATA COLLECTION AND ANALYSIS

Data collection and analysis conformed to the methods of the Cochrane Neonatal Review Group. We used the GRADE approach to assess the quality of evidence.

MAIN RESULTS

We included 39 studies enrolling 2843 infants.Ibuprofen (IV) versus placebo: IV Ibuprofen (3 doses) reduced the failure to close a PDA compared with placebo (typical relative risk (RR); 0.62 (95% CI 0.44 to 0.86); typical risk difference (RD); -0.18 (95% CI -0.30 to -0.06); NNTB 6 (95% CI 3 to 17); I² = 65% for RR and I² = 0% for RD; 2 studies, 206 infants; moderate-quality the evidence). One study reported decreased failure to close a PDA after single or three doses of oral ibuprofen compared with placebo (64 infants; RR 0.26, 95% CI 0.11 to 0.62; RD -0.44, 95% CI -0.65 to -0.23; NNTB 2, 95% CI 2 to 4; I² test not applicable).Ibuprofen (IV or oral) compared with indomethacin (IV or oral): Twenty-four studies (1590 infants) comparing ibuprofen (IV or oral) with indomethacin (IV or oral) found no significant differences in failure rates for PDA closure (typical RR 1.07, 95% CI 0.92 to 1.24; typical RD 0.02, 95% CI -0.02 to 0.06; I² = 0% for both RR and RD; moderate-quality evidence). A reduction in NEC (necrotising enterocolitis) was noted in the ibuprofen (IV or oral) group (18 studies, 1292 infants; typical RR 0.68, 95% CI 0.49 to 0.94; typical RD -0.04, 95% CI -0.07 to -0.01; NNTB 25, 95% CI 14 to 100; I² = 0% for both RR and RD; moderate-quality evidence). There was a statistically significant reduction in the proportion of infants with oliguria in the ibuprofen group (6 studies, 576 infants; typical RR 0.28, 95% CI 0.14 to 0.54; typical RD -0.09, 95% CI -0.14 to -0.05; NNTB 11, 95% CI 7 to 20; I² = 24% for RR and I² = 69% for RD; moderate-quality evidence). The serum/plasma creatinine levels 72 hours after initiation of treatment were statistically significantly lower in the ibuprofen group (11 studies, 918 infants; MD -8.12 µmol/L, 95% CI -10.81 to -5.43). For this comparison, there was high between-study heterogeneity (I² = 83%) and low-quality evidence.Ibuprofen (oral) compared with indomethacin (IV or oral): Eight studies (272 infants) reported on failure rates for PDA closure in a subgroup of the above studies comparing oral ibuprofen with indomethacin (IV or oral). There was no significant difference between the groups (typical RR 0.96, 95% CI 0.73 to 1.27; typical RD -0.01, 95% CI -0.12 to 0.09; I² = 0% for both RR and RD). The risk of NEC was reduced with oral ibuprofen compared with indomethacin (IV or oral) (7 studies, 249 infants; typical RR 0.41, 95% CI 0.23 to 0.73; typical RD -0.13, 95% CI -0.22 to -0.05; NNTB 8, 95% CI 5 to 20; I² = 0% for both RR and RD). There was low-quality evidence for these two outcomes. There was a decreased risk of failure to close a PDA with oral ibuprofen compared with IV ibuprofen (5 studies, 406 infants; typical RR 0.38, 95% CI 0.26 to 0.56; typical RD -0.22, 95% CI -0.31 to -0.14; NNTB 5, 95% CI 3 to 7; moderate-quality evidence). There was a decreased risk of failure to close a PDA with high-dose versus standard-dose of IV ibuprofen (3 studies 190 infants; typical RR 0.37, 95% CI 0.22 to 0.61; typical RD - 0.26, 95% CI -0.38 to -0.15; NNTB 4, 95% CI 3 to 7); I² = 4% for RR and 0% for RD); moderate-quality evidence).Early versus expectant administration of IV ibuprofen, echocardiographically-guided IV ibuprofen treatment versus standard IV ibuprofen treatment, continuous infusion of ibuprofen versus intermittent boluses of ibuprofen, and rectal ibuprofen versus oral ibuprofen were studied in too few trials to allow for precise estimates of any clinical outcomes.

AUTHORS' CONCLUSIONS

Ibuprofen is as effective as indomethacin in closing a PDA. Ibuprofen reduces the risk of NEC and transient renal insufficiency. Therefore, of these two drugs, ibuprofen appears to be the drug of choice. The effectiveness of ibuprofen versus paracetamol is assessed in a separate review. Oro-gastric administration of ibuprofen appears as effective as IV administration. To make further recommendations, studies are needed to assess the effectiveness of high-dose versus standard-dose ibuprofen, early versus expectant administration of ibuprofen, echocardiographically-guided versus standard IV ibuprofen, and continuous infusion versus intermittent boluses of ibuprofen. Studies are lacking evaluating the effect of ibuprofen on longer-term outcomes in infants with PDA.

Early treatment versus expectative management of patent ductus arteriosus in preterm infants: a multicentre, randomised, non-inferiority trial in Europe (BeNeDuctus trial)

BACKGROUND

Much controversy exists about the optimal management of a patent ductus arteriosus (PDA) in preterm infants, especially in those born at a gestational age (GA) less than 28 weeks. No causal relationship has been proven between a (haemodynamically significant) PDA and neonatal complications related to pulmonary hyperperfusion and/or systemic hypoperfusion. Although studies show conflicting results, a common understanding is that medical or surgical treatment of a PDA does not seem to reduce the risk of major neonatal morbidities and mortality. As the PDA might have closed spontaneously, treated children are potentially exposed to iatrogenic adverse effects. A conservative approach is gaining interest worldwide, although convincing evidence to support its use is lacking.

METHODS

This multicentre, randomised, non-inferiority trial is conducted in neonatal intensive care units. The study population consists of preterm infants (GA < 28 weeks) with an echocardiographic-confirmed PDA with a transductal diameter > 1.5 mm. Early treatment (between 24 and 72 h postnatal age) with the cyclooxygenase inhibitor (COXi) ibuprofen (IBU) is compared with an expectative management (no intervention intended to close a PDA). The primary outcome is the composite of mortality, and/or necrotising enterocolitis (NEC) Bell stage ≥ IIa, and/or bronchopulmonary dysplasia (BPD) defined as the need for supplemental oxygen, all at a postmenstrual age (PMA) of 36 weeks. Secondary outcome parameters are short term sequelae of cardiovascular failure, comorbidity and adverse events assessed during hospitalization and long-term neurodevelopmental outcome assessed at a corrected age of 2 years. Consequences regarding health economics are evaluated by cost effectiveness analysis and budget impact analysis.

DISCUSSION

As a conservative approach is gaining interest, we investigate whether in preterm infants, born at a GA less than 28 weeks, with a PDA an expectative management is non-inferior to early treatment with IBU regarding to the composite outcome of mortality and/or NEC and/or BPD at a PMA of 36 weeks.

TRIAL REGISTRATION

This trial is registered with the Dutch Trial Register NTR5479 (registered on 19 October 2015), the registry sponsored by the United States National Library of Medicine Clinicaltrials.gov NCT02884219 (registered May 2016) and the European Clinical Trials Database EudraCT 2017-001376-28 .

In vitro and in silico study of the biological activity of manganese(III) inverse-[9-MC-3]-metallacrowns and manganese(II) complexes with the anti-inflammatory drugs diclofenac or indomethacin

In the present contribution, the biological properties of four manganese complexes with the non-steroidal anti-inflammatory drugs sodium diclofenac (Nadicl) or indomethacin (Hindo) in the presence or absence of salicylaldoxime (Η₂sao), i.e. [Μn₆(O)₂(dicl)₂(sao)₆(CH₃OH)₆] 1, [Μn₆(O)₂(indo)₂(sao)₆(H₂O)₄], 2, [Μn(dicl)₂(CH₃OH)₄], 3, and [Μn(indo)₂(CH₃OH)₄], 4 are presented. More specifically, the in vitro cytotoxic effects of the complexes were evaluated against three cancer cell lines (HeLa, MCF-7 and A549 cells) as well as their combinatory activity with the well-known chemotherapeutic drugs irinotecan, cisplatin, paclitaxel and 5-fluorouracil. The biological activity of the complexes was investigated in vitro by studying their affinity to calf-thymus DNA and their binding towards bovine or human serum albumin (HSA). Molecular docking simulations on the crystal structure of HSA and human estrogen receptor alpha (hERa) were employed in order to study in silico the ability of the studied complexes to bind to these proteins.

The dark side of ibuprofen in the treatment of patent ductus arteriosus: could paracetamol be the solution?

INTRODUCTION

Patent ductus arteriosus (PDA) persistence is associated, in prematures, to several complications. The optimal PDA management is still under debate, especially regarding the best therapeutic approach and the time to treat. The available drugs are not exempt from contraindications and side effects; ibuprofen itself, although representing the first-choice therapy, can show nephrotoxicity and other complications. Paracetamol seems a valid alternative to classic nonsteroidal anti-inflammatory Drugs, with a lower toxicity. Areas covered: Through an analysis of the published literature on ibuprofen and paracetamol effects in preterm neonates, this review compares the available treatments for PDA, analyzing the mechanisms underlining ibuprofen-associated nephrotoxicity and the eventual paracetamol-induced hepatic damage, also providing an update of what has been yet demonstrated and a clear description of the still open issues. Expert Opinion: Paracetamol is an acceptable alternative in case of contraindication to ibuprofen; its toxicity, in this setting, is very low. Lower doses may be effective, with even fewer risks. In the future, paracetamol could represent an efficacious first-line therapy, although its safety, optimal dosage, and global impact have to be fully clarified through long-term trials, also in the perspective of an individualized and person-based therapy taking into account the extraordinary individual variability.

Effect on cerebral oxygenation of paracetamol for patent ductus arteriosus in preterm infants

Paracetamol seems to have similar success rates compared with indomethacin and ibuprofen in closing patent ductus arteriosus (PDA) in preterm infants, but with a better safety profile. The aim of our study was to evaluate the possible effects of paracetamol on cerebral oxygenation and cerebral blood flow velocity (CBFV). Infants with gestational age < 32 weeks with hemodynamically significant PDA (hsPDA) were prospectively studied by near infrared spectroscopy (NIRS) after the first dose of paracetamol (15 mg/kg) or ibuprofen (10 mg/kg). Cerebral regional oxygenation (rSO₂C) and fractional oxygen extraction ratio (FOEC) were recorded 30 min before (T₀) and 60 ± 20 min (T₁), 180 ± 30 min (T₂), and 360 ± 30 min (T₃) after the beginning of drug infusion. Moreover, mean flow velocity (Vmean) and resistance index (RI = PSV-DV/PSV) measured with Doppler ultrasound in pericallosal artery were recorded at the same times. Significant changes in rSO₂C and FOEC were not found during the study period within and between the groups. Similarly, Vmean did not vary in infants treated with paracetamol or ibuprofen, while RI decreased in the ibuprofen group.

CONCLUSION

The treatment of hsPDA with paracetamol does not affect cerebral oxygenation in very preterm infants; there were no differences in cerebral oxygenation in infants treated with paracetamol or ibuprofen, although in the ibuprofen group, the possible closure progression of PDA was associated to changes of RI. What is Known: • Paracetamol has similar success rates to indomethacin and ibuprofen in closing PDA with a better safety profile since previous studies did not report adverse effects. What is New: • Paracetamol does not affect cerebral oxygenation and perfusion in very preterm infants with PDA and this confirms its good safety profile.

Association of Placebo, Indomethacin, Ibuprofen, and Acetaminophen With Closure of Hemodynamically Significant Patent Ductus Arteriosus in Preterm Infants: A Systematic Review and Meta-analysis

IMPORTANCE

Despite increasing emphasis on conservative management of patent ductus arteriosus (PDA) in preterm infants, different pharmacotherapeutic interventions are used to treat those developing a hemodynamically significant PDA.

OBJECTIVES

To estimate the relative likelihood of hemodynamically significant PDA closure with common pharmacotherapeutic interventions and to compare adverse event rates.

DATA SOURCES AND STUDY SELECTION

The databases of MEDLINE, Embase, and the Cochrane Central Register of Controlled Trials were searched from inception until August 15, 2015, and updated on December 31, 2017, along with conference proceedings up to December 2017. Randomized clinical trials that enrolled preterm infants with a gestational age younger than 37 weeks treated with intravenous or oral indomethacin, ibuprofen, or acetaminophen vs each other, placebo, or no treatment for a clinically or echocardiographically diagnosed hemodynamically significant PDA.

DATA EXTRACTION AND SYNTHESIS

Data were independently extracted in pairs by 6 reviewers and synthesized with Bayesian random-effects network meta-analyses.

MAIN OUTCOMES AND MEASURES

Primary outcome: hemodynamically significant PDA closure; secondary: included surgical closure, mortality, necrotizing enterocolitis, and intraventricular hemorrhage.

RESULTS

In 68 randomized clinical trials of 4802 infants, 14 different variations of indomethacin, ibuprofen, or acetaminophen were used as treatment modalities. The overall PDA closure rate was 67.4% (2867 of 4256 infants). A high dose of oral ibuprofen was associated with a significantly higher odds of PDA closure vs a standard dose of intravenous ibuprofen (odds ratio [OR], 3.59; 95% credible interval [CrI], 1.64-8.17; absolute risk difference, 199 [95% CrI, 95-258] more per 1000 infants) and a standard dose of intravenous indomethacin (OR, 2.35 [95% CrI, 1.08-5.31]; absolute risk difference, 124 [95% CrI, 14-188] more per 1000 infants). Based on the ranking statistics, a high dose of oral ibuprofen ranked as the best pharmacotherapeutic option for PDA closure (mean surface under the cumulative ranking [SUCRA] curve, 0.89 [SD, 0.12]) and to prevent surgical PDA ligation (mean SUCRA, 0.98 [SD, 0.08]). There was no significant difference in the odds of mortality, necrotizing enterocolitis, or intraventricular hemorrhage with use of placebo or no treatment compared with any of the other treatment modalities.

CONCLUSIONS AND RELEVANCE

A high dose of oral ibuprofen was associated with a higher likelihood of hemodynamically significant PDA closure vs standard doses of intravenous ibuprofen or intravenous indomethacin; placebo or no treatment did not significantly change the likelihood of mortality, necrotizing enterocolitis, or intraventricular hemorrhage.

TRIAL REGISTRATION

PROSPERO Identifier: CRD42015015797.

The Ontogeny of Cerebrovascular Critical Closing Pressure

Premature infants are at risk of vascular neurological insults. Hypotension and hypertension are considered injurious, but neither condition is defined with consensus. Critical closing pressure (CrCP) is the arterial blood pressure (ABP) at which cerebral blood flow ceases. CrCP may serve to define subject-specific low or high ABP. Our objective was to quantify CrCP as a function of gestational age (GA). One hundred eighty-six premature infants with a GA range of 23-33 weeks, were monitored with umbilical artery catheters and transcranial Doppler insonation of middle cerebral artery flow velocity (FV) for 1-h sessions over the first week of life. CrCP was calculated using an impedance model derivation with Doppler-based estimations of cerebrovascular resistance and compliance. CrCP increased significantly with GA (r = 0.47; slope = 1.4 mmHg/week gestation), an association that persisted with multivariate analysis (p < 0.001). Higher diastolic ABP and higher GA were associated with increased CrCP (p <0.001 for both). CrCP increases significantly at the end of the second and beginning of the third trimester. The low CrCP observed in premature infants may explain their ability to tolerate low ABP without global cerebral infarct or hemorrhage.

Timing of surgical ligation and morbidities in very low birth weight infants

The present study examined whether early patent ductus arteriosus (PDA) surgical ligation at ≤2 weeks of life was associated with increased morbidities and mortality in very low birth weight infants (VLBWIs) who were diagnosed with hemodynamically significant (hs) PDA. Between December 2013 and December 2015, a total of 407 VLBWIs were admitted, of whom 145 (35.6%) infants were diagnosed with an hs PDA. The clinical data for these infants were retrospectively collected for analysis. Among the 145 VLBWIs with an hs PDA, 58 (40%) infants had surgical ligation for PDA; of these, 29 (50%) infants had early ligation (EL; ligation at ≤2 weeks of life) and 29 (50%) infants had late ligation (LL; ligation at ≥2 weeks of life). The mean gestational age and birth weight were significantly lower in the PDA-ligated group compared with the nonligated group. In addition, pulmonary hypertension at ≤1 week of life and neonatal seizures were significantly more prevalent in the ligated group (P < 0.05). Increased rate of ROP laser treatment, bronchopulmonary dysplasia, longer hospital stays, and longer duration of mechanical ventilation were found in ligated group (P < 0.05). However, the morbidities and mortality did not differ significantly between the EL and LL groups. Pulmonary hypertension at ≤1 week of life was significantly associated with LL (P = 0.019), which was consistently a risk factor for hs PDA ligation in our multivariable logistic regression analysis. EL was not significantly associated with increased hospital morbidities and mortality in VLBWIs with hs PDA. Pulmonary hypertension at ≤1 week of life can be a risk factor for the need for surgical ligation of hs PDA.

Recent Advances in Neonatal Pharmacotherapy

Objective:

To provide commentary and reviews and brief discussions in controversial or innovative recent advances in neonatal pharmacotherapy. To discuss cutting edge drug delivery systems that may become useful in neonatal drug delivery in the future.

Data Sources:

Articles were identified through searches of MEDLINE (1990–October 2005), key articles in the authors' files, and in some cases, through data generated and/or published by the author of a particular topic.

Data Selection:

Article selection and relevance to the topics under discussion was determined by individual authors.

Data Synthesis:

Therapeutic strategies addressed in this review include the use of hematopoietic growth factors including a simulated amniotic fluid preparation containing these growth factors for neonates with selected gastrointestinal problems, erythropoietin for neuroprotection following perinatal asphyxia, drug therapy advances in treatment of patent ductus arteriosus (PDA), evaluation of advances in transdermal drug delivery, and its potential application to neonates and advances in the treatment of persistent pulmonary hypertension (PPHN) of the newborn.

Conclusions:

Despite being over 30 years old, the practice of neonatology is as much of an art as a science. Advances in the basic science research have improved our understanding of use of pharmacologic agents in the premature and full-term neonate including drug disposition pathways. Expanding our knowledge on issues such as physiology of hematopoietic factors, the pharmacologic responses of conditions such as PDA and PPHN, and newer technologies for drug administration, as well as other pharmacologic reponses in the neonate are vital in the development of safe and efficacious treatments for neonates. Many questions remain unanswered, and every clinician must make an effort to contribute to the knowledge and understanding of pharmacotherapy in this patient population.

Near-infrared spectroscopy for detection of a significant patent ductus arteriosus

BACKGROUND

Near-infrared spectroscopy (NIRS) may assist with characterization of a hemodynamically significant patent ductus arteriosus (hsPDA) by measuring cerebral and renal saturation (Csat and Rsat) levels. We hypothesized that Csat and Rsat in preterm infants with an hsPDA would be decreased compared to those with no PDA or nonsignificant PDA.

METHODS

This non a-priori designed study retrospectively investigated clinical and ECHO characteristics of preterm infants <29 wk gestation who underwent routine NIRS monitoring. Logistic regression assessed association between NIRS measures and an hsPDA by ECHO.

RESULTS

Of 47 infants, 21 had a confirmed hsPDA by ECHO, 14 had a nonsignificant PDA, and 12 had no ECHO performed due to low clinical suspicion for PDA. Logistic regression adjusted for gestational age found that lower Rsat was associated with an hsPDA by ECHO (OR 0.9, 95% CI 0.83-0.98, P = 0.01). Using ROC curves, Rsat < 66% identified an hsPDA with a sensitivity of 81% and specificity of 77%, while Csat was not significant.

CONCLUSION

Low Rsat < 66% was associated with the presence of an hsPDA in the preterm infant. Csat may be preserved if cerebral autoregulation is largely intact. Bedside NIRS monitoring may reasonably increase suspicion for a significant PDA in the preterm infant.

Comparison of two dose regimens of ibuprofen for the closure of patent ductus arteriosus in preterm newborns

OBJECTIVE

To compare the efficacy of intravenous ibuprofen at high (20-10-10mg/kg/dose) and low doses (10-5-5mg/kg/dose) the closure of patent ductus arteriosus in preterm newborns.

METHODS

A cohort study with historical control of newborns that received high- and low-dose intravenous ibuprofen, from 2010 to 2013 in a neonatal intensive care unit, for closure of the patent ductus arteriosus, documented by echocardiography. Secondary outcomes included the number of ibuprofen cycles, incidence of bronchopulmonary dysplasia, necrotizing enterocolitis, changes in renal function, and death.

RESULTS

Seventy-seven patients received three doses of ibuprofen for the treatment of patent ductus arteriosus, with 33 receiving high-dose and 44 low-dose therapy. The ductus closed after the first cycle in 25 (56.8%) low-dose patients and in 17 (51.5%) high-dose patients (p>0.99). Sixteen patients received a second cycle of ibuprofen, and the ductus closed in 50% after low-dose and in 60% after high-dose therapy (p>0.99). Seven patients required surgery for ductus closure, 13.6% in the low-dose group and 3% in the high-dose group (p=0.22). Thirty-nine patients developed bronchopulmonary dysplasia, 50% in the low-dose group and 51.5% in the high-dose group (p>0.99). Twenty-two (50%) low-dose patients died vs. 15 (45.5%) high-dose patients (p=0.86).

CONCLUSIONS

There was no difference in closure of the ductus arteriosus or occurrence of adverse effects between the two dose regimens.

Pharmacological Closure of Patent Ductus Arteriosus: Selecting the Agent and Route of Administration

Opinions are divided regarding the management of a persistently patent ductus arteriosus (PDA). Some of the adverse effects associated with a large hemodynamically significant duct, including prolonged ventilation, pulmonary hemorrhage, bronchopulmonary dysplasia (BPD), necrotizing enterocolitis (NEC), intraventricular hemorrhage (IVH), and mortality, indicate that active management of infants with large ductal shunts may sometimes be necessary. Indomethacin and ibuprofen are the two US FDA-approved cyclooxygenase (COX) inhibitors used for the closure of a ductus in preterm babies. Both these drugs are effective in 70-80% of extremely low birthweight infants. Treatment with COX inhibitors may be associated with renal impairment, gastrointestinal hemorrhage, NEC, and spontaneous intestinal perforation when given concurrently with steroids, as well as changes in cerebrovascular auto-regulation. Ibuprofen appears to be a better choice for PDA closure, with a better side effect profile and efficacy that equals that of indomethacin. However, long-term outcome studies of ibuprofen are lacking, and prophylactic ibuprofen is ineffective in decreasing severe IVH. The choice of one drug over the other also depends on local availability of both drugs and the intravenous or enteral preparation. The oral preparation of ibuprofen appears as effective as the intravenous preparation. The use of paracetamol to close a hemodynamically significant PDA has increased in recent years. Paracetamol also decreases prostacyclin synthesis; however, unlike COX inhibitors, it does not have a peripheral vaso-constrictive effect and can be given to infants with contraindications to non-steroidal anti-inflammatory drugs. It appears to have similar efficacy based on limited data available from randomized trials. Until more data are available on efficacy, safety, and long-term outcomes, it cannot be recommended as the first choice.

Oral medications regarding their safety and efficacy in the management of patent ductus arteriosus

Patent ductus arteriosus (PDA) is a common clinical condition in preterm infants which is inversely related to birth weight and gestational age. Cyclooxygenase inhibitors such as indomethacin and ibuprofen which block the prostaglandin conversion from arachidonic acid are the most commonly used drugs for ductal closure. This review focuses on the safety and efficacy oral medications in the management of PDA in preterm infants. Ibuprofen seems to be the first choice due to its higher safety profile, as it is associated with fewer gastrointestinal and renal side effects when compared to indomethacin. PDA closure rates are better with oral than with intravenous ibuprofen probably due to the pharmacokinetic of the drug. However, these medications were reported to be associated with several adverse including transient renal failure, gastrointestinal bleeding and perforation, hyperbilirubinemia and platelet dysfunction. Paracetamol seems be an alternative to PDA therapy with lower adverse events and side effects.

Ibuprofen Versus Indomethacin for Medical Closure of the Patent Arterial Duct: A Pooled Analysis by Route of Administration

Introduction:

Preterm infants are at increased risk of having a patent arterial duct (PAD). PADs may cause congestive heart failure, respiratory distress, necrotizing enterocolitis, and renal impairment. Consequently, in some infants, it becomes necessary to attempt closure of the PAD. Surgical closure can be difficult in small infants and is not without its risks; thus, medical closure offers advantages. Cyclooxygenase inhibitors have been used for medical closure of the PAD with both ibuprofen and indomethacin having been used clinically.

Methods:

We performed a systematic review of the literature to identify all studies comparing ibuprofen and indomethacin. Studies comparing ibuprofen and indomethacin for closure of the PAD in premature infants were included in the meta-analysis. A subanalysis was performed to compare the route of administration. Efficacy endpoints studied were PAD closure and surgical ligation while adverse effects studied were death in the first month of life, necrotizing enterocolitis, gastrointestinal bleeding, intestinal perforation, bronchopulmonary dysplasia in the first month of life, Grade 3 or 4 intraventricular hemorrhage, and change in the serum creatinine after treatment.

Results:

Ibuprofen and indomethacin were equally effective in closing the PAD in premature infants and demonstrated no difference in the incidence of adverse events. In respect to the route of administration, oral ibuprofen was as effective as intravenous indomethacin. When comparing both drugs via the intravenous route, the only difference noted between the ibuprofen and indomethacin was that ibuprofen was associated with a lesser increase in serum creatinine after treatment.

Conclusion:

Ibuprofen and indomethacin are equally effective in PAD closure without any difference in the incidence of adverse events. Importantly, oral ibuprofen was as effective as intravenous indomethacin.

Ontogeny of cerebrovascular critical closing pressure

BACKGROUND

Premature infants are at risk of vascular neurologic insults. Hypotension and hypertension are considered injurious, but neither condition is defined with consensus. Cerebrovascular critical closing pressure (CrCP) is the arterial blood pressure (ABP) at which cerebral blood flow (CBF) ceases. CrCP may serve to define subject-specific low or high ABP. Our objective was to determine the ontogeny of CrCP.

METHODS

Premature infants (n = 179) with gestational age (GA) from 23-31 wk had recordings of ABP and middle cerebral artery flow velocity twice daily for 3 d and then daily for the duration of the first week of life. All infants received mechanical ventilation. CrCP was calculated using an impedance-model derivation with Doppler-based estimations of cerebrovascular resistance and compliance. The association between GA and CrCP was determined in a multivariate analysis.

RESULTS

The median (interquartile range) CrCP for the cohort was 22 mm Hg (19-25 mm Hg). CrCP increased significantly with GA (r = 0.6; slope = 1.4 mm Hg/wk gestation), an association that persisted with multivariate analysis (P < 0.0001).

CONCLUSION

CrCP increased significantly from 23 to 31 wk gestation. The low CrCP observed in very premature infants may explain their ability to tolerate low ABP without global cerebral infarct or hemorrhage.

Ibuprofen for the treatment of patent ductus arteriosus in preterm or low birth weight (or both) infants

BACKGROUND

Indomethacin is used as standard therapy to close a patent ductus arteriosus (PDA) but is associated with reduced blood flow to several organs. Ibuprofen, another cyclo-oxygenase inhibitor, may be as effective as indomethacin with fewer adverse effects.

OBJECTIVES

To determine the effectiveness and safety of ibuprofen compared with indomethacin, other cyclo-oxygenase inhibitor, placebo or no intervention for closing a patent ductus arteriosus in preterm, low birth weight, or preterm and low birth weight infants.

SEARCH METHODS

We searched The Cochrane Library, MEDLINE, EMBASE, Clincialtrials.gov, Controlled-trials.com, and www.abstracts2view.com/pas in May 2014.

SELECTION CRITERIA

Randomised or quasi-randomised controlled trials of ibuprofen for the treatment of a PDA in newborn infants.

DATA COLLECTION AND ANALYSIS

Data collection and analysis conformed to the methods of the Cochrane Neonatal Review Group.

MAIN RESULTS

We included 33 studies enrolling 2190 infants.Two studies compared intravenous (iv) ibuprofen versus placebo (270 infants). In one study (134 infants) ibuprofen reduced the incidence of failure to close a PDA (risk ratio (RR) 0.71, 95% confidence interval (CI) 0.51 to 0.99; risk difference (RD) -0.18, 95% CI -0.35 to -0.01; number needed to treat for an additional beneficial outcome (NNTB) 6, 95% CI 3 to 100). In one study (136 infants), ibuprofen reduced the composite outcome of infant mortality, infants who dropped out, or infants who required rescue treatment (RR 0.58, 95% CI 0.38 to 0.89; RD -0.22, 95% CI -0.38 to -0.06; NNTB 5, 95% CI 3 to 17). One study (64 infants) compared oral ibuprofen with placebo and noted a significant reduction in failure to close a PDA (RR 0.26, 95% CI 0.11 to 0.62; RD -0.44, 95% CI -0.65 to -0.23; NNTB 2, 95% CI 2 to 4).Twenty-one studies (1102 infants) reported failure rates for PDA closure with ibuprofen (oral or iv) compared with indomethacin (oral or iv). There was no significant difference between the groups (typical RR 1.00, 95% CI 0.84 to 1.20; I(2) = 0%; typical RD 0.00, 95% CI -0.05 to 0.05; I(2) = 0%). The risk of developing necrotising enterocolitis (NEC) was reduced for ibuprofen (16 studies, 948 infants; typical RR 0.64, 95% CI 0.45 to 0.93; typical RD -0.05, 95% CI -0.08 to -0.01; NNTB 20, 95% CI 13 to 100; I(2) = 0% for both RR and RD). The duration of ventilatory support was reduced with ibuprofen (oral or iv) compared with iv or oral indomethacin (six studies, 471 infants; mean difference (MD) -2.4 days, 95% CI -3.7 to -1.0; I(2) = 19%).Eight studies (272 infants) reported on failure rates for PDA closure in a subgroup of the above studies comparing oral ibuprofen with indomethacin (oral or iv). There was no significant difference between the groups (typical RR 0.96, 95% CI 0.73 to 1.27; typical RD -0.01, 95% CI -0.12 to 0.09). The risk of NEC was reduced with oral ibuprofen compared with indomethacin (oral or iv) (seven studies, 249 infants; typical RR 0.41, 95% CI 0.23 to 0.73; typical RD -0.13, 95% CI -0.22 to -0.05; NNTB 8, 95% CI 5 to 20; I(2) = 0% for both RR and RD). There was a decreased risk of failure to close a PDA with oral ibuprofen compared with iv ibuprofen (four studies, 304 infants; typical RR 0.41, 95% CI 0.27 to 0.64; typical RD -0.21, 95% CI -0.31 to -0.12; NNTB 5, 95% CI 3 to 8). Transient renal insufficiency was less common in infants who received ibuprofen compared with indomethacin. High dose versus standard dose of iv ibuprofen, early versus expectant administration of iv ibuprofen, echocardiographically guided iv ibuprofen treatment vs. standard iv ibuprofen treatment and continuous infusion of ibuprofen vs. intermittent boluses of ibuprofen and long-term follow-up were studied in too few trials to draw any conclusions.

AUTHORS' CONCLUSIONS

Ibuprofen is as effective as indomethacin in closing a PDA and currently appears to be the drug of choice. Ibuprofen reduces the risk of NEC and transient renal insufficiency. Oro-gastric administration of ibuprofen appears as effective as iv administration. To make further recommendations, studies are needed to assess the effectiveness of high-dose versus standard-dose ibuprofen, early versus expectant administration of ibuprofen, echocardiographically guided versus standard iv ibuprofen, and continuous infusion versus intermittent boluses of ibuprofen. Studies are lacking evaluating the effect of ibuprofen on longer-term outcomes in infants with PDA.

Neonatal pain management

The past 2-3 decades have seen dramatic changes in the approach to pain management in the neonate. These practices started with refuting previously held misconceptions regarding nociception in preterm infants. Although neonates were initially thought to have limited response to painful stimuli, it was demonstrated that the developmental immaturity of the central nervous system makes the neonate more likely to feel pain. It was further demonstrated that untreated pain can have long-lasting physiologic and neurodevelopmental consequences. These concerns have resulted in a significant emphasis on improving and optimizing the techniques of analgesia for neonates and infants. The following article will review techniques for pain assessment, prevention, and treatment in this population with a specific focus on acute pain related to medical and surgical conditions.

Pain management in newborns

As a standard of care for preterm/term newborns effective pain management may improve their clinical and neurodevelopmental outcomes. Neonatal pain is assessed using context-specific, validated, and objective pain methods, despite the limitations of currently available tools. Therapeutic approaches reducing invasive procedures and using pharmacologic, behavioral, or environmental measures are used to manage neonatal pain. Nonpharmacologic approaches like kangaroo care, facilitated tucking, non-nutritive sucking, sucrose, and others can be used for procedural pain or adjunctive therapy. Local/topical anesthetics, opioids, NSAIDs/acetaminophen and other sedative/anesthetic agents can be incorporated into NICU protocols for managing moderate/severe pain or distress in all newborns.

Outcomes of primary ligation of patent ductus arteriosus compared with secondary ligation after pharmacologic failure in very-low-birth-weight infants

This study aimed to determine whether primary surgical closure of patent ductus arteriosus (PDA) is a risk factor for morbidity and mortality compared with secondary surgical ligation. The study enrolled 178 very-low-birth-weight infants. The surgical group included 34 patients who did not respond to pharmacologic intervention and eventually required ligation of their PDA as well as 35 patients who underwent direct ligation because of contraindications to the use of oral ibuprofen. The overall outcomes for the primary and secondary ligation groups were compared. The outcome during hospitalization showed no statistically significant difference in terms of morbidity and mortality between the two groups. The group that had primary ligation for PDA experienced more complications associated with premature birth such as lower gestational age and birth weight. The two groups did not differ significantly in terms of overall outcomes.

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.

Observational study of cerebral hemodynamics during dopamine treatment in hypotensive ELBW infants on the first day of life

OBJECTIVE

To evaluate cerebral hemodynamics during dopamine treatment in hypotensive (mean arterial blood pressure (MABP)<gestational age) extremely low birth weight (ELBW) infants.

STUDY DESIGN

Continuous monitoring of cerebral blood flow velocity (CBFv), MABP and PCO2 was performed in hypotensive ELBW infants on the first day of life, beginning with an ∼15-min baseline reading and continued during advancing dopamine infusion until MABP was optimized. Physiological variables and CBFv reactivity were compared before and after MABP was optimized.

RESULT

Fifteen hypotensive ELBW infants (625±174 g; 24 (23 to 24.8) weeks) were studied. Mean CBFv increased from 10.9±3.7 to 15.7±5.7 cm s(-1) (P=0.001) simultaneously as MABP increased from 22.3±2.8 to 35.2±9.7 mm Hg (P<0.001). Mean CBFv reactivity (95% confidence interval (CI)) was 3.9 (1.6 to 6.2) %mm Hg(-1). Nine infants died and/or developed severe intraventricular hemorrhage (IVH).

CONCLUSION

Mean CBFv increased pressure-passively as MABP was optimized by dopamine treatment in very sick hypotensive ELBW infants on the first day of life.

Preservation of the metabolic rate of oxygen in preterm infants during indomethacin therapy for closure of the ductus arteriosus

BACKGROUND

The aim of this study was to assess and quantify the effects of indomethacin on cerebral blood flow (CBF), oxygen extraction fraction (OEF), and cerebral metabolic rate of oxygen (CMRO2) in preterm infants undergoing treatment for a patent ductus arteriosus (PDA).

METHODS

CBF and CMRO2 were measured before and after the first dose of a 3-d course of indomethacin to close hemodynamically significant PDA in preterm neonates. Indocyanine-green (ICG) concentration curves were acquired before and after indomethacin injection to quantify CBF and CMRO2.

RESULTS

Eight preterm neonates (gestational age, 27.6 ± 0.5 wk; birth weight, 992 ± 109 g; 6 males:2 females) were treated at a median age of 4.5 d (range, 4-21 d). Indomethacin resulted in an average CBF decrease of 18% (pre- and post-CBF = 12.9 ± 1.3 and 10.6 ± 0.8 ml/100 g/min, respectively) and an OEF increase of 11% (pre- and post-OEF = 0.38 ± 0.02 and 0.42 ± 0.02, respectively) but no significant change in CMRO2 (pre- and post-CMRO2 = 0.83 ± 0.07 and 0.76 ± 0.07 ml O2/100 g/min, respectively). Corresponding mean blood pressure (BP), arterial oxygen saturation (SaO2), heart rate, and end-tidal carbon dioxide tension levels remained unchanged.

CONCLUSION

Indomethacin resulted in significant reduction in CBF but did not alter CMRO2 because of a compensatory increase in OEF.

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

BACKGROUND

Indomethacin is used as standard therapy to close a patent ductus arteriosus (PDA) but is associated with reduced blood flow to several organs. Ibuprofen, another cyclo-oxygenase inhibitor, may be as effective as indomethacin with fewer side effects.

OBJECTIVES

To determine the efficacy and safety of ibuprofen for closing a PDA in preterm and/or low birth weight infants. Seperate comparisons are presented for 1. ibuprofen (iv) compared with placebo; 2. ibuprofen (oral) compared with placebo; 3. ibuprofen (oral or iv) compared with other cyclo-oxygenase inhibitors (given iv or orally); 4. ibuprofen (oral) versus indomethacin (given iv or orally); 5. ibuprofen (oral) versus iv ibuprofen; 6. high dose versus standard dose of iv ibuprofen; 7. early versus expectant administration of iv ibuprofen.

SEARCH METHODS

We searched The Cochrane Library, MEDLINE, EMBASE, Clincialtrials.gov, Controlled-trials.com, www.abstracts2view.com/pas, and personal files in July 2012.

SELECTION CRITERIA

Randomised or quasi-randomised controlled trials of ibuprofen for the treatment of a PDA in newborn infants.

DATA COLLECTION AND ANALYSIS

Data collection and analysis conformed to the methods of the Cochrane Neonatal Review Group.

MAIN RESULTS

Twenty-seven studies are included in this review. One study (n = 136) compared iv ibuprofen versus placebo. Ibuprofen reduced the composite outcome of infant deaths, infants who dropped out or required rescue treatment; risk ratio (RR) 0.58 (95% confidence interval (CI) 0.38 to 0.89); risk difference (RD) -0.22 (95% CI -0.38 to -06); number needed to benefit (NNTB) 5 (95% CI 3 to 17). One study (n = 64) compared oral ibuprofen with placebo. There was a significant reduction in the failure rate to close a PDA; RR 0.26 (95% CI 0.11 to 0.62); RD -0.44 (95% CI -0.65 to -0.23); NNTB 2 (95% CI 2 to 4). Failure rates for PDA closure with ibuprofen (oral or iv) compared with indomethacin (oral or iv) was reported in 20 studies (n = 1019 infants). There was no significant difference between the groups; typical RR 0.98 (95% CI 0.80 to 1.20) I(2) = 0%; typical RD -0.01 (95% CI -0.06 to 0.05); I(2) = 0%. The risk of developing necrotising enterocolitis (NEC) was reduced for ibuprofen (15 studies (n = 865); typical RR 0.68 (95% CI 0.47 to 0.99); typical RD -0.04 (95% CI -0.08 to -0.00; (P = 0.04); NNTB 25 (95% CI 13, infinity); I(2) = 0%). The duration of ventilatory support was reduced with ibuprofen (oral or iv) compared with iv or oral indomethacin (six studies, n = 471) mean difference (MD) -2.35 days (95% CI -3.71 to -0.99); I(2) = 19%. Failure rates for PDA closure with oral ibuprofen compared with indomethacin (oral or iv) were reported in seven studies (n = 189 infants). There was no significant difference between the groups; typical RR 0.82 (95% CI 0.52 to 1.29); typical RD -0.06 (95% CI -0.18 to 0.06). The risk of NEC was reduced with oral ibuprofen compared with indomethacin (oral or iv) six studies (n = 166); typical RR 0.44 (95% CI 0.23 to 0.82); RD -0.15 (95% CI -0.25 to -0.04); NNTB 7 (95% CI 4 to 25). There was no heterogeneity for this outcome. There was a decreased risk of failure to close a PDA with oral ibuprofen compared with iv ibuprofen, three studies (n = 236) typical RR 0.37 (95% CI 0.23 to 0.61); typical RD -0.24 (95% CI -0.35 to -0.13); NNTB 4 (95% CI 3 to 8). There was less evidence of transient renal insufficiency in infants who received ibuprofen compared with indomethacin. High dose versus standard dose of iv ibuprofen and early versus expectant administration of iv ibuprofen have only been studied in two trials.

AUTHORS' CONCLUSIONS

Ibuprofen is as effective as indomethacin in closing a PDA and reduces the risk of NEC and transient renal insufficiency. Given the reduction in NEC ibuprofen currently appears to be the drug of choice. Oro-gastric administration of ibuprofen appears at least as effective as iv administration. Too few patients have been enrolled in studies assessing the effectiveness of a high dose of ibuprofen versus the standard dose and early versus expectant administration of ibuprofen to make recommendations. Studies are needed to evaluate the effect of ibuprofen compared with indomethacin treatment on longer-term outcomes in infants with PDA.

Impact of patient selection on outcomes of PDA in very low birth weight infants

AIM

The aim of this study was to observe whether our patient selection maximized the benefits of PDA ligation by comparing the outcomes in a surgically ligated group of PDA to a medically closed group.

STUDY DESIGN

If a hemodynamically significant ductus arteriosus (HSDA) was found to meet both clinical and echocardiographic criteria (stage≥3), as proposed by NcNamara and Hellman, medical treatment was initiated with oral ibuprofen (maximum 2 courses). If the PDA of these patients failed to close medically, timed surgical closure was performed.

RESULT

Medical treatment was effective in 75 (72%) cases, and 29 (28%) patients required surgical ligation. The mean gestational age and birth weight were each significantly lower and the initial PDA shunt size was significantly larger in the surgically treated group. Additionally, the mean durations of mechanical ventilation, oxygen dependence and hospital admission were significantly longer in the surgically ligated group. However, our logistic regression analysis demonstrated no statistically significant difference in the outcomes of hospitalization (CLD, NEC, ARF, sepsis, IVH, ROP, PVL and death) between the two groups.

CONCLUSION

Comprehensive HSDA patient selection may maximize the benefits of timed PDA ligation without adverse outcomes in very low birth weight infants.

The SafeBoosC phase II randomised clinical trial: a treatment guideline for targeted near-infrared-derived cerebral tissue oxygenation versus standard treatment in extremely preterm infants

Near-infrared spectroscopy-derived regional tissue oxygen saturation of haemoglobin (rStO2) reflects venous oxygen saturation. If cerebral metabolism is stable, rStO2 can be used as an estimate of cerebral oxygen delivery. The SafeBoosC phase II randomised clinical trial hypothesises that the burden of hypo- and hyperoxia can be reduced by the combined use of close monitoring of the cerebral rStO2 and a treatment guideline to correct deviations in rStO2 outside a predefined target range.

AIMS

To describe the rationale for and content of this treatment guideline.

METHODS

Review of the literature and assessment of the quality of evidence and the grade of recommendation for each of the interventions.

RESULTS AND CONCLUSIONS

A clinical intervention algorithm based on the main determinants of cerebral perfusion-oxygenation changes during the first hours after birth was generated. The treatment guideline is presented to assist neonatologists in making decisions in relation to cerebral oximetry readings in preterm infants within the SafeBoosC phase II randomised clinical trial. The evidence grades were relatively low and the guideline cannot be recommended outside a research setting.

Oral ibuprofen versus intravenous indomethacin for closure of patent ductus arteriosus in very low birth weight infants

BACKGROUND

The purpose of this study is to compare the effects and complications of pharmacologic closure of patent ductus arteriosus (PDA) by intravenous indomethacin or oral ibuprofen in neonates weighing <1500 g at birth [very low birth weight (VLBW) infants].

METHODS

This is a retrospective study of infants treated with intravenous indomethacin (0.2 mg/kg initially followed by two doses at 24-hour intervals) or oral ibuprofen (10 mg/kg initially followed an interval of 24 hours by two doses of 5 mg/kg) for symptomatic PDA in a neonatal intensive care unit at a medical center in Taiwan during the period of January 2005 to December 2010.

RESULTS

A total of 88 infants received indomethacin and 52 received oral ibuprofen. Among the survivors, the closure rate without surgical ductal ligation was 70.5% (62/88) in the indomethacin group and 61.5% (32/52) in the ibuprofen group (p = 0.342). The incidence rates of oliguria and elevated serum creatinine were significantly lower in the ibuprofen group (p =0.002 and p =0.022, respectively). There was no significant difference in incidence of upper gastrointestinal hemorrhage or necrotizing enterocolitis between the ibuprofen and indomethacin groups (17.3% versus 23.9%; 3.8% versus 11.3%).

CONCLUSION

In infants with VLBW, oral ibuprofen is as effective as intravenous indomethacin for closure of PDA and is associated with significantly fewer cases of necrotizing enterocolitis among infants with birth body weights <1250 g and significantly lower rates of elevated creatinine levels among neonates with birth body weights ranging from 1000 to 1500 g.

Treatment of patent ductus arteriosus (PDA) using ibuprofen: renal side-effects in VLBW and ELBW newborns

OBJECTIVES

This study aims to determine whether or not treatment of preterm neonates with PDA using IV ibuprofen can impair renal function and in what range of birth weights and gestational ages the risk of major renal side-effects due to ibuprofen is highest.

METHODS

134 preterm newborns with PDA were enrolled and randomized to receive either placebo or a 3-day-course (10, 5 and 5 mg/kg) of IV ibuprofen. 67 newborns (mGA: 27(+3) w and mBW: 989 g) with PDA received ibuprofen.

RESULTS

Subdividing the infants according to BW and to GA, the values of creatinine and BUN were only significantly higher than initial values at the end of the therapy in newborns with a BW ≤1000 g and/or GA ≤26 weeks. Renal impairment is greater the lower the weight and gestational age of the infant at birth.

CONCLUSIONS

Ibuprofen significantly impairs renal function in preterm infants with a GA ≤26 weeks and/or in ELBW neonates, while it may be considered safe for infants with a BW >1000 g and/or GA >26 weeks. Thus, before starting therapy with IV ibuprofen, it is essential to take into account the BW and GA of newborns and the effective need for treatment from the point of view of the ratio of risks to benefits, due to its substantial renal side-effects.

Patent ductus arteriosus in premature neonates

Persistent patency of the ductus arteriosus is a major cause of morbidity and mortality in premature infants. In infants born prior to 28 weeks of gestation, a haemodynamically significant patent ductus arteriosus (PDA) can cause cardiovascular instability, exacerbate respiratory distress syndrome, prolong the need for assisted ventilation and increase the risk of bronchopulmonary dysplasia, intraventricular haemorrhage, renal dysfunction, cerebral palsy and mortality. We review the pathophysiology, clinical features and assessment of haemodynamic significance, and provide a rigorous appraisal of the quality of evidence to support current medical and surgical management of PDA of prematurity. Cyclo-oxygenase inhibitors such as indomethacin and ibuprofen remain the mainstay of medical therapy for PDA, and can be used both for prophylaxis as well as for rescue therapy to achieve PDA closure. Surgical ligation is also effective and is used in infants who do not respond to medical management. Although both medical and surgical treatment have proven efficacy in closing the ductus, both modalities are associated with significant adverse effects. Because the ductus does undergo spontaneous closure in some premature infants, improved and early identification of infants most likely to develop a symptomatic PDA could help in directing treatment to the at-risk infants and allow others to receive expectant management.

Echocardiography as a guide for patent ductus arteriosus ibuprofen treatment and efficacy prediction

OBJECTIVE

To evaluate echocardiography criteria in predicting the response to ibuprofen treatment.

DESIGN

A prospective cohort study of preterm infants untreated or treated with ibuprofen for patent ductus arteriosus.

SETTING

Three academic neonatal intensive care units.

PATIENTS

Two hundred fifty-two preterm infants of 27-31 wks gestation.

INTERVENTIONS

Ibuprofen treatment within the first 5 days of life was indicated when at least two out of four conventional echocardiography criteria were observed: ductal diameter >2 mm, left-right ductal shunt maximum velocity <2 m/sec, mean flow velocity in left pulmonary artery >0.4 m/sec, and end-diastolic flow velocity in left pulmonary artery >0.2 m/sec.

MEASUREMENTS AND MAIN RESULTS

Of the infants analyzed, 135 had a closed ductus at an average age of 1.9 ± 0.9 days, and 43 had an open ductus but <2 predefined criteria. Seventy-four infants (29%) received ibuprofen on day 2.2 ± 1.1. Sixteen infants failed ibuprofen and nine had to undergo surgical ligation. The left-right ductal shunt maximum velocity criterion had the best negative predictive value for treatment response, while the ductal diameter criterion had the best positive predictive value.

CONCLUSIONS

Echocardiography may be a useful tool to help patent ductus arteriosus management. A combined use of ductal diameter and left-right ductal shunt maximum velocity criteria allows a more accurate prediction of the response of infants with patent ductus arteriosus to ibuprofen treatment.

Patent ductus arteriosus: are current neonatal treatment options better or worse than no treatment at all?

Although a moderate-sized patent ductus arteriosus (PDA) needs to be closed by the time a child is 1-2 years old, there is great uncertainty about whether it needs to be closed during the neonatal period. Although 95% of neonatologists believe that a moderate-sized PDA should be closed if it persists in infants (born before 28 weeks) who still require mechanical ventilation, the number of neonatologists who treat a PDA when it occurs in infants who do not require mechanical ventilation varies widely. Both the high likelihood of spontaneous ductus closure and the absence of randomized controlled trials, specifically addressing the risks and benefits of neonatal ductus closure, add to the current uncertainty. New information suggests that early pharmacologic treatment has several important short-term benefits for the preterm newborn. By contrast, ductus ligation, while eliminating the detrimental effects of a PDA on lung development, may create its own set of morbidities that counteract many of the benefits derived from ductus closure.

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.

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.

The effects of closed tracheal suctioning plus volume guarantee on cerebral hemodynamics

OBJECTIVE

To compare the effects of open tracheal suctioning (OS) plus intermittent mandatory ventilation (IMV) vs. closed tracheal suctioning (CS) plus volume guarantee ventilation (VG) on changes in mean cerebral blood-flow velocity (CBFv) of ventilated very low birth weight (VLBW) infants.

STUDY DESIGN

A total of 75 normotensive, ventilated VLBW infants (with normal cranial ultrasounds) had monitoring of mean CBFv, PCO2 and mean arterial blood pressure (MABP) before, during and after 220 tracheal suctioning sessions during the first week of life. Multiple linear regression analysis was used to determine the factor(s) influencing the magnitude of relative changes from baseline in mean CBFv after suctioning.

RESULT

In all, 49 VLBW infants receiving IMV had monitoring during 124 OS sessions between July 2002 and May 2005; 26 VLBW infants receiving VG had monitoring during 96 CS sessions between January 2006 and July 2007. The average magnitude of relative changes in mean CBFv was significantly less with CS+VG, and was associated with the magnitude of relative changes in PCO2 and suctioning-ventilator group.

CONCLUSION

The average magnitude of relative changes in mean CBFv was reduced in VLBW infants with CS+VG vs. OS+IMV.

Cerebral Oxygenation Monitoring: A Strategy to Detect IVH and PVL

Premature infants are at risk for intraventricular hemorrhage (IVH) and periventricular leukomalacia (PVL) theorized to be a result from fluctuations in cerebral blood flow. Monitoring cerebral oxygenation offers a method to observe changes in cerebral blood flow that may be beneficial for detecting and preventing IVH and PVL. This article explains the potential for cerebral oxygenation monitoring in detecting IVH and PVL using cerebral oximetry, reviews current knowledge known about cerebral oxygenation, and describes current challenges for cerebral oxygenation to be the next neuroprotective vital sign.