Subgroup analysis of the early paracetamol trial to preterm infants found haemodynamic changes and improved oxygenation

Blood pressure increase preceded spontaneous and paracetamol-induced, early ductal closure in very preterm infants

AIM

To investigate the blood pressure (BP) and ductal calibre patterns associated with early ductal closure in very low gestational age (<32 weeks) infants.

METHODS

Blood pressure was continuously measured intra-arterially among 43 infants participating in a randomised, double-blind trial of 4 days prophylactic intravenous paracetamol. Early closure of the ductus was verified by daily ultrasound examinations. The BP recordings, before and after the verified ductal closure, were examined and compared to control infants without ductal closure. In the 24-h preceding the ultrasound-verified ductal closure, periods of increased BP were searched and identified as suggestive ductal closure time points. In control infants without ductal closure, BP trends were examined during the corresponding age.

RESULTS

Mean arterial BP increased significantly before ductal closure (p < 0.001) and stayed higher than in the control group. Mean BP during the 8 h preceding closure significantly predicted the ductal closure [OR 2.094 (95% CI 1.209-3.630), p = 0.008], and multiple potential confounders failed to abolish this association. A linear decrease pattern in ductal calibre was significantly associated with the ductal closure.

CONCLUSION

Blood pressure increased and stabilised before the early ductal closure, offering potential implications on treatment strategies of very premature infants.

Long-term neurodevelopmental outcomes in very low birth weight infants with and without patent ductus arteriosus: A retrospective case control observational study

BACKGROUND

Patent ductus arteriosus (PDA) has been associated with early morbidities and long-term developmental problems in very preterm infants.

AIMS

The aim of this study is to investigate the effect of patent ductus arteriosus and medical treatment on long-term developmental outcomes in very low birth weight infants.

STUDY DESIGN

This is a retrospective case control observational study.

SUBJECT

The study included preterm infants who were born before 30 weeks' gestation and birth weight less than 1,500 g and underwent neurodevelopmental testing at a corrected age of 24 months during follow-up in our centre. The results of neurodevelopmental assessment using the Bayley Scales of Infant Development II at 24 months of corrected age and other morbidities were recorded.

RESULTS

Of 820 infants screened, the 2-year data of 647 infants (78%) were analysed. The mean gestational age was 27.4 weeks (±1.7 weeks), mean birth weight was 980 g (±250 g) and 283 (44%) of the infants received pharmaceutical treatment for hemodynamically significant PDA. The prevalence of neurodevelopmental impairment was higher in infants with PDA compared to those without PDA (odds ratio [OR], 1.6; 95% CI, 1.13-2.29; chi-square, Fisher's exact test P = .009). However, when birth weight and gestational age were corrected for as covariates and other risk factors were added to the analysis, PDA alone was not an independent risk factor for neurodevelopmental problems (OR, 1.12; 95% CI, 0.824-1.549; P = .450). There was no difference between the groups who received ibuprofen or paracetamol for PDA.

CONCLUSION

Although we have not found an association between hemodynamically significant PDA and poor neurodevelopment, this potentially needs to be investigated.

Paracetamol preceding very preterm birth: Is it safe?

INTRODUCTION

The use of paracetamol for pain relief in pregnancy is common. However, the influence of paracetamol on the perinatal adaptation of high-risk infants has not been studied. These data are important for safety, since another inhibitor of prostaglandin synthesis is harmful to infants born very preterm and increases serious morbidity. We studied whether the use of paracetamol had an adverse influence on neonatal adaptation and the outcomes of infants during the first hospitalization.

MATERIAL AND METHODS

We studied the patient records of high-risk mothers and their infants born before 32 weeks of gestation for multiple variables over a period of 84 months in Oulu University Hospital, a regional tertiary care hospital caring for high-risk deliveries and providing neonatal intensive care. In a matched cohort setting, the exposition was defined as paracetamol use <24 h before childbirth. The controls had consumed no paracetamol up to 1 week before delivery. Infants with major anomalies were excluded. The primary outcome was defined as the need for early interventional treatments for the preterm infants. Outcomes during the first hospitalization were also studied.

RESULTS

Altogether, 170 fetuses from 149 mothers were exposed to paracetamol during the study period. The control population, delivering during the same period, consisted of 118 non-exposed fetuses from 104 mothers. Among them, the mothers were pairwise matched according to their medications, amniotic fluid leakage time, clinical infections, and delivery mode. After matching, 72 mothers/group remained, resulting in 88 paracetamol-exposed infants and 85 controls. No perinatal adverse reactions were detected. There were no differences in either circulatory support during the first postnatal day or in the risk for major diseases during the first hospitalization. Paracetamol-exposed infants needed fewer acute delivery room therapies (51.1% vs 65.9%, mean difference -14.89; 95% confidence interval -0.29 to -0.003). Maternal total paracetamol dose in the 1 week before delivery correlated positively with Apgar scores.

CONCLUSIONS

Antenatal paracetamol given within 24 h before birth had no adverse effects on extremely or very preterm infants. The long-term safety of paracetamol and the potential acute benefits for preterm infants during perinatal transition remain to be proven in larger, prospective settings.

Management Practices During Perinatal Respiratory Transition of Very Premature Infants

The present review considers some controversial management practices during extremely premature perinatal transition. We focus on perinatal prevention and treatment of respiratory distress syndrome (RDS) in immature infants. New concerns regarding antenatal corticosteroid management have been raised. Many fetuses are only exposed to potential adverse effects of the drug. Hence, the formulation and the dosage may need to be modified. Another challenge is to increase the fraction of the high-risk fetuses that benefit from the drug and to minimize the harmful effects of the drug. On the other hand, boosting anti-inflammatory and anti-microbial properties of surfactant requires further attention. Techniques of prophylactic surfactant administration to extremely immature infants at birth may be further refined. Also, new findings suggest that prophylactic treatment of patent ductus arteriosus (PDA) of a high-risk population rather than later selective closure of PDA may be preferred. The TREOCAPA trial (Prophylactic treatment of the ductus arteriosus in preterm infants by acetaminophen) evaluates, whether early intravenous paracetamol decreases the serious cardiorespiratory consequences following extremely premature birth. Lastly, is inhaled nitric oxide (iNO) used in excess? According to current evidence, iNO treatment of uncomplicated RDS is not indicated. Considerably less than 10% of all very premature infants are affected by early persistence of pulmonary hypertension (PPHN). According to observational studies, effective ventilation combined with early iNO treatment are effective in management of this previously fatal disease. PPHN is associated with prolonged rupture of fetal membranes and birth asphyxia. The lipopolysaccharide (LPS)-induced immunotolerance and hypoxia-reperfusion-induced oxidant stress may inactivate NO-synthetases in pulmonary arterioles and terminal airways. Prospective trials on iNO in the management of PPHN are indicated. Other pulmonary vasodilators may be considered as comparison drugs or adjunctive drugs. The multidisciplinary challenge is to understand the regulation of pregnancy duration and the factors participating the onset of extremely premature preterm deliveries and respiratory adaptation. Basic research aims to identify deficiencies in maternal and fetal tissues that predispose to very preterm births and deteriorate the respiratory adaptation of immature infants. Better understanding on causes and prevention of extremely preterm births would eventually provide effective antenatal and neonatal management practices required for the intact survival.

Prophylactic cyclo-oxygenase inhibitor drugs for the prevention of morbidity and mortality in preterm infants: a network meta-analysis

BACKGROUND

Patent ductus arteriosus (PDA) is associated with significant morbidity and mortality in preterm infants. Cyclooxygenase inhibitors (COX-I) may prevent PDA-related complications. Controversy exists on which COX-I drug is the most effective and has the best safety profile in preterm infants.

OBJECTIVES

To compare the effectiveness and safety of prophylactic COX-I drugs and 'no COXI prophylaxis' in preterm infants using a Bayesian network meta-analysis (NMA).

SEARCH METHODS

Searches of Cochrane CENTRAL via Wiley, OVID MEDLINE and Embase via Elsevier were conducted on 9 December 2021. We conducted independent searches of clinical trial registries and conference abstracts; and scanned the reference lists of included trials and related systematic reviews.

SELECTION CRITERIA

We included randomised controlled trials (RCTs) that enrolled preterm or low birth weight infants within the first 72 hours of birth without a prior clinical or echocardiographic diagnosis of PDA and compared prophylactic administration of indomethacin or ibuprofen or acetaminophen versus each other, placebo or no treatment.

DATA COLLECTION AND ANALYSIS

We used the standard methods of Cochrane Neonatal. We used the GRADE NMA approach to assess the certainty of evidence derived from the NMA for the following outcomes: severe intraventricular haemorrhage (IVH), mortality, surgical or interventional PDA closure, necrotizing enterocolitis (NEC), gastrointestinal perforation, chronic lung disease (CLD) and cerebral palsy (CP).

MAIN RESULTS

We included 28 RCTs (3999 preterm infants). Nineteen RCTs (n = 2877) compared prophylactic indomethacin versus placebo/no treatment, 7 RCTs (n = 914) compared prophylactic ibuprofen versus placebo/no treatment and 2 RCTs (n = 208) compared prophylactic acetaminophen versus placebo/no treatment. Nine RCTs were judged to have high risk of bias in one or more domains.We identified two ongoing trials on prophylactic acetaminophen. Bayesian random-effects NMA demonstrated that prophylactic indomethacin probably led to a small reduction in severe IVH (network RR 0.66, 95% Credible Intervals [CrI] 0.49 to 0.87; absolute risk difference [ARD] 43 fewer [95% CrI, 65 fewer to 16 fewer] per 1000; median rank 2, 95% CrI 1-3; moderate-certainty), a moderate reduction in mortality (network RR 0.85, 95% CrI 0.64 to 1.1; ARD 24 fewer [95% CrI, 58 fewer to 16 more] per 1000; median rank 2, 95% CrI 1-4; moderate-certainty) and surgical PDA closure (network RR 0.40, 95% CrI 0.14 to 0.66; ARD 52 fewer [95% CrI, 75 fewer to 30 fewer] per 1000; median rank 2, 95% CrI 1-2; moderate-certainty) compared to placebo. Prophylactic indomethacin resulted in trivial difference in NEC (network RR 0.76, 95% CrI 0.35 to 1.2; ARD 16 fewer [95% CrI, 42 fewer to 13 more] per 1000; median rank 2, 95% CrI 1-3; high-certainty), gastrointestinal perforation (network RR 0.92, 95% CrI 0.11 to 3.9; ARD 4 fewer [95% CrI, 42 fewer to 137 more] per 1000; median rank 1, 95% CrI 1-3; moderate-certainty) or CP (network RR 0.97, 95% CrI 0.44 to 2.1; ARD 3 fewer [95% CrI, 62 fewer to 121 more] per 1000; median rank 2, 95% CrI 1-3; low-certainty) and may result in a small increase in CLD (network RR 1.10, 95% CrI 0.93 to 1.3; ARD 36 more [95% CrI, 25 fewer to 108 more] per 1000; median rank 3, 95% CrI 1-3; low-certainty). Prophylactic ibuprofen probably led to a small reduction in severe IVH (network RR 0.69, 95% CrI 0.41 to 1.14; ARD 39 fewer [95% CrI, 75 fewer to 18 more] per 1000; median rank 2, 95% CrI 1-4; moderate-certainty) and moderate reduction in surgical PDA closure (network RR 0.24, 95% CrI 0.06 to 0.64; ARD 66 fewer [95% CrI, from 82 fewer to 31 fewer] per 1000; median rank 1, 95% CrI 1-2; moderate-certainty) compared to placebo. Prophylactic ibuprofen may result in moderate reduction in mortality (network RR 0.83, 95% CrI 0.57 to 1.2; ARD 27 fewer [95% CrI, from 69 fewer to 32 more] per 1000; median rank 2, 95% CrI 1-4; low-certainty) and leads to trivial difference in NEC (network RR 0.73, 95% CrI 0.31 to 1.4; ARD 18 fewer [95% CrI, from 45 fewer to 26 more] per 1000; median rank 1, 95% CrI 1-3; high-certainty), or CLD (network RR 1.00, 95% CrI 0.83 to 1.3; ARD 0 fewer [95% CrI, from 61 fewer to 108 more] per 1000; median rank 2, 95% CrI 1-3; low-certainty). The evidence is very uncertain on effect of ibuprofen on gastrointestinal perforation (network RR 2.6, 95% CrI 0.42 to 20.0; ARD 76 more [95% CrI, from 27 fewer to 897 more] per 1000; median rank 3, 95% CrI 1-3; very low-certainty). The evidence is very uncertain on the effect of prophylactic acetaminophen on severe IVH (network RR 1.17, 95% CrI 0.04 to 55.2; ARD 22 more [95% CrI, from 122 fewer to 1000 more] per 1000; median rank 4, 95% CrI 1-4; very low-certainty), mortality (network RR 0.49, 95% CrI 0.16 to 1.4; ARD 82 fewer [95% CrI, from 135 fewer to 64 more] per 1000; median rank 1, 95% CrI 1-4; very low-certainty), or CP (network RR 0.36, 95% CrI 0.01 to 6.3; ARD 70 fewer [95% CrI, from 109 fewer to 583 more] per 1000; median rank 1, 95% CrI 1-3; very low-certainty). In summary, based on ranking statistics, both indomethacin and ibuprofen were equally effective (median ranks 2 respectively) in reducing severe IVH and mortality. Ibuprofen (median rank 1) was more effective than indomethacin in reducing surgical PDA ligation (median rank 2). However, no statistically-significant differences were observed between the COX-I drugs for any of the relevant outcomes.

AUTHORS' CONCLUSIONS

Prophylactic indomethacin probably results in a small reduction in severe IVH and moderate reduction in mortality and surgical PDA closure (moderate-certainty), may result in a small increase in CLD (low-certainty) and results in trivial differences in NEC (high-certainty), gastrointestinal perforation (moderate-certainty) and cerebral palsy (low-certainty). Prophylactic ibuprofen probably results in a small reduction in severe IVH and moderate reduction in surgical PDA closure (moderate-certainty), may result in a moderate reduction in mortality (low-certainty) and trivial differences in CLD (low-certainty) and NEC (high-certainty). The evidence is very uncertain about the effect of acetaminophen on any of the clinically-relevant outcomes.

Inflammatory biomarkers in very preterm infants during early intravenous paracetamol administration

BACKGROUND

Paracetamol promotes early closure of patent ductus arteriosus (PDA), and it may affect inflammation after preterm birth.

OBJECTIVE

The aim of this study was to evaluate the association between paracetamol treatment and serum inflammatory biomarkers in very preterm infants with respiratory distress.

STUDY DESIGN

The infants were randomly assigned to intravenous paracetamol or placebo during the first 4 days of life, and others received a lower dose of paracetamol unblinded. Serum samples were used for the analysis of 10 cytokines, C-reactive protein (CRP) and malondialdehyde (MDA). The impact of paracetamol on the biomarkers was evaluated, based on the levels during the early (<60 h) and the later (60-120 h) postnatal age.

RESULTS

Altogether, 296 serum samples from 31 paracetamol and 25 placebo group infants were analysed. Paracetamol had no effect on cytokine levels during the first 60 h when most induced PDA contractions took place. Later paracetamol treatment was associated with lower serum levels of several cytokines, including interleukin (IL-) 10, interferon gamma-induced protein (IP-) 10, and monocyte chemoattractant protein-1. CRP levels were lower in the paracetamol group during the early treatment. Amongst the infants who had severe morbidities, MDA was higher (p = .045), regardless of paracetamol treatment.

CONCLUSION

No significant differences in the cytokine levels were evident between the treatment and placebo groups. However, during early treatment, CRP levels were lower in the paracetamol group. To clarify whether this was due to a decrease in cardiopulmonary distress, or a distinct anti-inflammatory effect, requires further studies.

Intravenous paracetamol for neonates: long-term diseases not escalated during 5 years of follow-up

OBJECTIVE

To evaluate the long-term adverse reactions of paracetamol in children who required intensive care shortly after birth. Paracetamol is a widely used analgesic in neonates, but the long-term studies are lacking. Previous epidemiological studies have reported associations between early paracetamol intake and diseases in childhood.

DESIGN

Five-year follow-up cohort of children who required intensive care shortly after birth.

SETTING

Single tertiary care hospital; neonatal and paediatric intensive care units.

INTERVENTIONS

Intravenous paracetamol was administered for pain and discomfort to the neonates during their intensive care, while for the control infants, it was not available.

MAIN OUTCOME MEASURES

The primary outcome was the incidence of asthma; secondary outcomes were neonatal diseases and long-term morbidities (atopic dermatitis, inflammatory bowel disease, autism, speech disorders, cerebral palsy). Long-term morbidities were adjusted based on antenatal and neonatal risk factors.

RESULTS

We screened all neonates admitted to the intensive care units soon after birth in Oulu University Hospital, Oulu, Finland, during 1 October 2007 to 31 December 2013. Altogether, 1552 infants needed intensive care. Of them, 735 (47%) were treated with intravenous paracetamol. We obtained their long-term data from the Finnish National Institute for Health and Welfare, including all physician-made diagnoses from all primary healthcare units and hospitals in Finland. We found no difference in the asthma incidence or in other long-term morbidities between paracetamol-treated and non-exposed infants.

CONCLUSIONS

Intravenous paracetamol given to neonates did not associate with childhood disorders compared with the non-exposed infants during the 5-year follow-up. The previous hypothesis that early paracetamol use causes childhood morbidities was not confirmed.