Indomethacin prophylaxis to prevent intraventricular hemorrhage: association between incidence and timing of drug administration

Acquired Brain Injuries Across the Perinatal Spectrum: Pathophysiology and Emerging Therapies

The development of the central nervous system can be directly disrupted by a variety of acquired factors, including infectious, inflammatory, hypoxic-ischemic, and toxic insults. Influences external to the fetus also impact neurodevelopment, including placental health, maternal comorbidities, adverse experiences, environmental exposures, and social determinants of health. Acquired perinatal brain insults tend to affect the developing brain in a stage-specific manner that reflects the susceptible cell types, developmental processes, and risk factors present at the time of the insult. In this review, we discuss the pathophysiology, neurodevelopmental outcomes, and management of common acquired perinatal brain conditions. In the fetal brain, we divide insults based on trimester, and in the postnatal brain, we focus on common pathologies that have a presentation dependent on gestational age at birth: white matter injury and germinal matrix hemorrhage/intraventricular hemorrhage in preterm infants and hypoxic-ischemic encephalopathy in term infants. Although specific treatments for fetal and newborn brain disorders are currently limited, we emphasize therapies in preclinical or early clinical phases of the development pipeline. The growing number of novel cell type- and stage-specific emerging therapies suggests that in the near future we may have a dramatically improved ability to treat acquired perinatal brain disorders and to mitigate the associated neurodevelopmental consequences.

Brain Damage in the Preterm Infant: Clinical Aspects and Recent Progress in the Prevention and Treatment

Although the prevalence of brain injury and related neurodevelopmental disabilities resulting from preterm birth are major public health concerns, there are no definite neuroprotective strategies to prevent or reduce brain injury. The pattern of brain injury seen in preterm infants has evolved into more subtle lesions that are still essential to diagnose regarding neurodevelopmental outcomes. There is no specific effective method for the treatment of premature infant brain injury, and the focus of clinical treatment is still on prevention. Prevention of this injury requires insight into the pathogenesis, but many gaps exist in our understanding of how neonatal treatment procedures and medications impact cerebral hemodynamics and preterm brain injury. Many studies provide evidence about the prevention of premature infant brain injury, which is related to some drugs (such as erythropoietin, melatonin, mesenchymal stem cells, etc.). However, there are still some controversies about the quality of research and the effectiveness of therapy. This review aims to recapitulate the results of preclinical studies and provide an update on the latest developments around etiological pathways, prevention, and treatment.

A predictive clinical model for moderate to severe intraventricular hemorrhage in very low birth weight infants

IMPORTANCE

Intraventricular hemorrhage (IVH) occurs in 15-45% of all very low birth weight (VLBW) preterm infants. Despite improvements in the perinatal care, the incidence of IVH remains high. As more preterm infants survive, there will be a larger burden of neurodevelopmental abnormalities borne by former preterm infants.

OBJECTIVE

The objective of this study was to develop a predictive clinical model of IVH risk within the first few hours of life in an effort to augment perinatal counseling and guide the timing of future targeted therapies aimed at preventing or slowing the progression of disease.

DESIGN

This is a prospective observational cohort study of VLBW infants born in the NICU at John's Hopkins Children's Center from 2011 to 2019. The presence and severity of IVH was defined on standard head ultrasound screening (HUS) using the modified Papile classification. Clinical variables were identified as significant using absolute risk regression from a general linear model. The model predictors included clinically meaningful variables that were not collinear.

SETTING

This study took place at the Johns Hopkins Children's Center Level IV NICU.

PARTICIPANTS

The study sample included VLBW infants treated in the neonatal intensive care unit (NICU) at John's Hopkins Children's Center from 2011 to 2019. A total of 683 infants included in the study had no or grade I IVH, and 115 infants had grades II through IV IVH. Exclusion criteria included admission to the JHH NICU after 24 h of age, BW > 1500 g, and failure to consent.

MAIN OUTCOME

The main outcome of this study was the presence of grades II-IV IVH on standard head ultrasound screening using the modified Papile classification [1].

RESULTS

A total of 798 VLBW infants were studied in this cohort and 14.4% had moderate to severe IVH. Fifty four percent of the cohort was black, 33% white, and half of the cohort was male. A higher gestational age, 5-min Apgar score, hematocrit, and platelet count were significantly associated with decreased incidence of IVH in a multi-predictor model (ROC 0.826).

CONCLUSION AND RELEVANCE

In the face of continued lack of treatments for IVH, prevention is still a primary goal to avoid long-term developmental sequela. This model can be used for perinatal counseling and may provide important information during the narrow therapeutic window for targeted prevention therapies.

Development of an integrated risk scale for prediction of shunt placement after neonatal intraventricular hemorrhage

OBJECTIVE

Neonatal intraventricular hemorrhage (IVH) is a major cause of mortality and morbidity, particularly following premature birth. Even after the acute phase, posthemorrhagic hydrocephalus is a long-term complication, frequently requiring permanent ventriculoperitoneal shunt (VPS) placement. Currently, there are no risk classification methods integrating the constellation of clinical data to predict short- and long-term prognosis in neonatal IVH. To address this need, the authors developed a two-part machine learning approach for predicting short- and long-term outcomes after diagnosis of neonatal IVH. Integrating both maternal and neonatal characteristics, they developed a binary classifier to predict short-term mortality risk and a clinical scale to predict the long-term risk of VPS placement.

METHODS

Neonates with IVH were identified from the Optum Clinformatics Data Mart administrative claims database. Matched maternal and childbirth characteristics were obtained for all patients. The primary endpoints of interest were short-term (30 day) mortality and long-term VPS placement. Classification of short-term mortality risk was evaluated using 5 different machine learning approaches and the best-performing method was validated using a withheld validation subset. Prediction of long-term shunt risk was performed using a multivariable Cox regression model with stepwise variable selection, which was subsequently converted to an easily applied integer risk scale.

RESULTS

A total of 5926 neonates with IVH were identified. Most patients were born before 32 weeks' gestation (67.2%) and with low birth weight (81.2%). Empirical 30-day mortality risk was 10.9% across all IVH grades and highest among grade IV IVH (34.3%). Among the neonates who survived > 30 days, actuarial 12-month postdiagnosis risk of shunt placement was 5.4% across all IVH grades and 31.3% for grade IV IVH. The optimal short-term risk classifier was a random forest model achieving an area under the receiver operating characteristic curve of 0.882 with important predictors ranging from gestational age to diverse comorbid medical conditions. Selected features for long-term shunt risk stratification were IVH grade, respiratory distress syndrome, disseminated intravascular coagulation, and maternal preeclampsia or eclampsia. An integer risk scale, termed the Shunt Prediction After IVH in Neonates (SPAIN) scale, was developed from these 4 features, which, evaluated on withheld cases, demonstrated improved risk stratification compared with IVH grade alone (Harrell's concordance index 0.869 vs 0.852).

CONCLUSIONS

In a large cohort of neonates with IVH, the authors developed a two-pronged, integrated, risk classification approach to anticipate short-term mortality and long-term shunt risk. The application of such approaches may improve the prognostication of outcomes and identification of higher-risk individuals who warrant careful surveillance and early intervention.

Use of Prophylactic Indomethacin in Preterm Infants: A Systematic Review and Meta-Analysis

BACKGROUND

Prophylactic indomethacin has been widely used as an effective intervention for reducing mortalities and morbidities in preterm infants including the cardiopulmonary and neurodevelopmental morbidities such as intraventricular hemorrhage (IVH), but many studies have reported contradictory outcomes regarding its significance. Therefore, we aim to systematically review and meta-analyze the data of prophylactic indomethacin on preterm infants.

METHODS

Our systematic search included the following databases: Pubmed, Google Scholar, Scopus, Web of Science, The New York Academy of Medicine (NYAM), Virtual health library (VHL), and the System for Information on Grey Literature in Europe (SIGLE) to include studies that assessed the use of prophylactic indomethacin in preterm infants until 12 August 2021.

RESULTS

The final list of our included studies is comprised of 23 randomized trials and cohort studies. Among all the studies outcomes, significant favorable outcome was lowering the rate of PDA, surgical PDA ligation (P < 0.001) and severe IVH (P = 0.008) while no significance was recorded with BPD, pulmonary hemorrhage, intraventricular hemorrhage, necrotizing enterocolitis, intestinal perforation, mortality, and length of hospital stay.

CONCLUSION

Since the meta-analysis results regarding effectiveness of prophylactic indomethacin varied based on the study design particularly with regard to outcomes such as surgical PDA ligation and severe IVH, this warrants the need for more evidence regarding the effectiveness of prophylactic indomethacin in very low birth weight infants.

Prophylactic Indomethacin in extremely preterm infants: association with death or BPD and observed early serum creatinine levels

OBJECTIVES

To identify the relationship between prophylactic indomethacin (PI) administration and (1) mortality and bronchopulmonary dysplasia (BPD) at 36-week postmenstrual age (PMA) (primary outcome), and (2) to evaluate for PI-associated acute kidney injury.

STUDY DESIGN

Retrospective cohort investigation of 22-28 weeks gestation infants (N = 1167) who were admitted to Nationwide Children's Hospital on postnatal days 0-1 between May 2009 and September 2017 and survived ≥24-h postnatal. The associations of PI treatment with mortality or BPD, and other secondary outcomes, were evaluated via multivariable robust-error-variance Poisson regression.

RESULTS

The adjusted risks of death or BPD (1.02, 95% CI: 0.83, 1.25), BPD (0.97, 95% CI: 0.77, 1.21), and death 1.33 (95% CI: 0.84, 2.10) by 36-week PMA were unchanged following PI treatment after multivariable adjustment. No changes in mean creatinine levels were detected in exposed versus unexposed infants to suggest PI-induced AKI.

CONCLUSION

Prophylactic indomethacin treatment was unrelated to mortality or BPD outcomes.

Germinal Matrix-Intraventricular Hemorrhage: A Tale of Preterm Infants

Germinal matrix-intraventricular hemorrhage (GM-IVH) is a common intracranial complication in preterm infants, especially those born before 32 weeks of gestation and very-low-birth-weight infants. Hemorrhage originates in the fragile capillary network of the subependymal germinal matrix of the developing brain and may disrupt the ependymal lining and progress into the lateral cerebral ventricle. GM-IVH is associated with increased mortality and abnormal neurodevelopmental outcomes such as posthemorrhagic hydrocephalus, cerebral palsy, epilepsy, severe cognitive impairment, and visual and hearing impairment. Most affected neonates are asymptomatic, and thus, diagnosis is usually made using real-time transfontanellar ultrasound. The present review provides a synopsis of the pathogenesis, grading, incidence, risk factors, and diagnosis of GM-IVH in preterm neonates. We explore brief literature related to outcomes, management interventions, and pharmacological and nonpharmacological prevention strategies for GM-IVH and posthemorrhagic hydrocephalus.

Neuroprotective effect of indomethacin in normal perfusion pressure breakthrough phenomenon

Loss of cerebral autoregulation in normal perfusion pressure breakthrough (NPPB) phenomenon has been reported in other Central Nervous System diseases such as neonatal intraventricular haemorrhage. Several studies have demonstrated that low-dose indomethacin prevents this latter condition. A previous rat model was used to resemble NPPB phenomenon. Study animals were distributed in 4 groups that received 3 doses of indomethacin at different concentrations prior to fistula occlusion 60 days after its creation. Control animals received saline solution. Intracranial pressure (ICP) increased in all groups following fistula creation, whereas mean arterial pressure (MAP) and cerebral perfusion pressure (CPP) decreased as a manifestation of cerebral hypoperfusion and intracranial hypertension. The administration of indomethacin was associated with raised MAP and CPP, as well as decreased ICP. Sodium fluorescein extravasation was slight in study animals when comparing with control ones. Histological analysis evidenced diffuse ischaemic changes with signs of neuronal apoptosis in all brain layers in control animals. These findings were only focal and slight in study animals. The results suggest the usefulness of indomethacin to revert, at least partially, the haemodynamic effects of NPPB phenomenon in this experimental model, as well as to reduce BBB disruption and histological ischemia observed in absence of indomethacin.

A single-dose indomethacin prophylaxis for reducing perinatal brain injury in extremely low birth weight infants: a non-inferiority analysis

OBJECTIVE

To evaluate whether rates of perinatal brain injury among extremely low birth weight infants are comparable between two treatments: single-dose indomethacin prophylaxis (SGL-IP) (0.2 mg/kg, given once) vs. standard-dose indomethacin prophylaxis (STD-IP) (0.1 mg/kg/day, 3 days).

METHODS

In this retrospective study, the primary outcome was perinatal brain injury (neuro-imaging evidence of intraventricular hemorrhage or periventricular leukomalacia) or death before discharge. A non-inferior efficacy of an SGL-IP regimen compared with a STD-IP regimen was determined by calculating the adjusted difference in the risk of the primary outcome using a multivariable logistic regression model. A 10-percentage point non-inferiority margin was favored.

RESULTS

Prevalence rates of primary outcome were 41.7% in the SGL-IP group (n = 403) and 42.5% in the STD-IP group (n = 509) (adjusted risk difference: -1.2, 95% CI: -7.6 to +5.2, p = 0.71).

CONCLUSION

Use of a single prophylactic indomethacin dose was as effective as a standard regimen in preventing perinatal brain injury.

Development and validation of a novel scoring system to predict severe intraventricular hemorrhage in very low birth weight infants

OBJECTIVE

We sought to develop and validate a novel scoring system for the prediction of severe intraventricular hemorrhage (SIVH) in very low birth weight infants (VLBWI).

METHODS

This retrospective cohort multicenter study included 615 VLBWI born between 24 and 32 weeks gestational age (GA). Multivariable logistic regression analyses were used to determine which factors evaluated within the first 5 days of life were associated with SIVH and the weights of these variables. The accuracy of the predictive scoring system was prospectively tested in the same units.

RESULTS

The final SIVH scoring system included the following variables: antenatal steroid therapy, GA, birth weight (BW), 1-min Apgar score, mechanical ventilation and hypotension. The SIVH scores used to divide the subjects into three tiers (low-risk (<5), moderate-risk (5-8) and high-risk (>8)) were developed based on these variables. Of infants with a score below 5, 1.2% (4/339) developed SIVH. Of those with a score above 8, 42.5% (17/40) developed SIVH. The scores were successfully verified in 99 VLBWI.

CONCLUSIONS

These findings suggest that among infants with a score >8, the incidence of SIVH is significantly higher. This scoring system can be used to predict the incidence of SIVH during the first 5 days after birth and may contribute to the early intervention in and prevention of SIVH.

Risk factors associated with intraventricular hemorrhage in extremely premature neonates

: Intraventricular hemorrhage (IVH) is a significant cause of morbidity in extremely premature infants despite many advances in neonatal intensive care. We conducted an institutional retrospective review aimed to correlate risk factors associated with IVH. Clinical variables reported to the Vermont-Oxford Network on less than 30 weeks gestational age infants over a 5-year period were evaluated with Pearson's chi-square and multivariate logistic regression. Of 618 infants born less than 30-week gestational age, 178 (28.8%) experienced IVH. Of those less than 1000 g, 105 (36.5%) of 288 infants experienced IVH. Multivariate analysis revealed that thrombocytopenia [odds ratio (OR) 2.03, 95% confidence interval (CI) 1.30-3.19, P = 0.0020] and cardiopulmonary resuscitation (CPR) ± intubation at delivery (OR 1.84, 95% CI 1.12-3.02, P = 0.0162) were independently associated with IVH. Among infants less than 1000 g, thrombocytopenia (OR 2.09, 95% CI 1.22-3.60, P = 0.0077) and CPR ± intubation at delivery (OR 2.01, 95% CI 1.10-3.68, P = 0.0229) were also significantly associated with IVH. IVH is a complex phenomenon with many contributing risk factors. In our study, infants less than 30-week gestational age and less than 1000 g revealed thrombocytopenia and CPR ± intubation in delivery room were independently associated with IVH. These data should alert clinicians to those neonates most likely to suffer IVH.

Early lumbar puncture and risk of intraventricular hemorrhage in very low birth weight infants

BACKGROUND

Lumbar puncture (LP) is the gold standard for diagnosing meningitis; however it is unknown whether early LP (≤3days of life) is associated with increased risk of intraventricular hemorrhage (IVH) in very low birth weight (VLBW) infants.

OBJECTIVE

To determine whether early LP in VLBW infants is associated with severe IVH.

METHODS

VLBW infants from a cohort of 1,158,789 infants discharged from 382 neonatal intensive care units (1997-2015) were enrolled.

EXCLUSION CRITERIA

infants with major congenital anomalies, outborns, died/transferred prior to day of life 3, and those who had an LP performed only after day of life 3. Logistic regression was used to determine the association between early LP and the incidence of severe IVH (IVH grades 3/4) by 28days of life for each day of life from day 0 (birth) to day 3, adjusting for clinical covariates.

RESULTS

106,461 infants were included: 754 received an LP on Day-0, 640 on Day-1, 559 on Day-2 and 483 on Day-3. Severe IVH occurred in 4% (4130/104,025) of the infants in the no LP group and 9% (217/2436) of the LP group. Severe IVH was higher for infants with early LP: adjusted OR (95% confidence interval)=2.64 (1.96-3.54) on Day-0; 2.21 (1.61-3.04) on Day-1; 1.55 (1.03-2.34) on Day-2; and 2.25 (1.50-3.38) on Day-3.

CONCLUSIONS

Early LP was associated with severe IVH in VLBW infants by 28days of life. LP is either a surrogate for an unrecognized factor or is itself associated with an increased risk of IVH.

Ante-, peri- and postnatal factors associated with intraventricular hemorrhage in very premature infants

BACKGROUND

Intraventricular hemorrhage (IVH) is one of the most serious complications in preterm infants and is associated with neurological sequelae and mortality. Over the past few decades, the rate of IVH has decreased due to improved neonatal intensive care. However, up to 15-25% of very and extremely premature infants (<32 and <28weeks of pregnancy (WOP) respectively) still suffer from IVH.

STUDY PURPOSE

The aim of this study was to perform an updated, multicenter analysis to identify ante-, peri, and postnatal factors other than gestational age/birth weight associated with IVH of any grade in a large cohort of very and extremely premature infants.

METHODS

We performed a retrospective analysis in a prospectively conducted multicenter cohort study between 01/01/1998-31/12/2012 at 5 level 3 perinatal centers. All relevant ante-, peri- and neonatal data were collected and univariate as well as multivariate logistic regression analysis was performed.

RESULTS

765 inborn infants with a gestational age<32 WOP were enrolled into this study (369 (48.2%) female; 396 (51.8%) male). Birth weight ranged from 315g to 2200g (mean 1149.7g, SD 371.9g); 279 (36.5%) were born ≤27+6 WOP and 486 (63.5%)≥28+0 WOP. IVH was seen in 177 (23.1%) patients. Multivariate analysis revealed that in addition to higher gestational age (OR 0.7, CI [0.6-0.8]), antenatal steroid treatment (OR 0.3, CI [0.2-0.6]) and caesarian section without uterine contraction (OR 0.6, CI [0.4-0.9]) were associated with a lower rate of IVH while RDS (OR 5.6, CI [1.3-24.2]), pneumothorax (OR 2.8, CI [1.4-5.5]) and use of catecholamines (OR 2.7, CI [1.7-4.5]) were associated with an increased risk of IVH. After exclusion of gestational age and birth weight from multivariate analysis, early onset sepsis (OR 1.6, CI [1.01-2.7]) and patent ductus arteriosus (OR 1.9, CI [1.1-3.1]) were associated with a higher rate of IVH. In addition, univariate analysis revealed that Apgar scores at 5min (p<0.001), BDP/ROP/NEC (p<0.001), mechanical ventilation (p<0.001) and inhalative nitric oxide (p<0.001) were significantly associated with IVH.

CONCLUSIONS

Our comprehensive analysis demonstrated that the occurrence of IVH in very premature infants is significantly associated with ante-, peri- and postnatal factors being either related to the degree of immaturity or indicating a critical clinical course after birth. The analysis reiterates the necessity for a very close cooperation between obstetricians and neonatologists to reduce the incidence of IVH in this susceptible cohort.

Hospital volume and mortality due to preterm patent ductus arteriosus

BACKGROUND

Preterm patent ductus arteriosus (PDA) requires neonatal intensive care. The relationship between hospital volume and mortality of PDA remains poorly understood.

METHODS

This was a retrospective observational study, using a national inpatient database in Japan. We identified patients who were diagnosed with PDA; exclusion criteria were as follows: (i) other cardiac complications; (ii) mild PDA treated without oral/i.v. indomethacin, surgery, or catheter intervention; (iii) age >1 year at admission; (iv) gestational age ≥32 weeks; (v) death within 3 days of admission; and (vi) transferal to other hospitals. Information was collected using the Japanese Diagnosis Procedure Combination database from July 2010 to March 2013. Hospital volume was defined as the average annual number of neonates with gestational age <32 weeks at each hospital. The outcome measure was in-hospital mortality.

RESULTS

A total of 2437 eligible patients treated at 199 hospitals were included. Low, medium, and high volume were defined as average annual number of preterm infants <34, 34-65, and >65, respectively. There were no significant differences in in-hospital mortality according to hospital volume. In-hospital mortality was identical in patients who received indomethacin alone, surgical or catheter intervention, or both after adjustment for patient background.

CONCLUSIONS

There was no significant relationship between hospital volume and in-hospital mortality due to preterm PDA. Centralization of patients with this condition may not be necessary.

Intraventricular Hemorrhage and Platelet Indices in Extremely Premature Neonates

Intraventricular hemorrhage (IVH) is a multifactorial disorder, the most important risk factors of which are prematurity and low birth weight. Disturbances in cerebral blood flow, inherent fragility of the germinal matrix vasculature, and platelet/coagulation disturbances are the 3 major pathogenic mechanisms. In this context, we investigated the role of platelet indices and several maternal and neonatal characteristics in the development of IVH through a retrospective cohort analysis of 130 extremely premature neonates, 24% of whom presented with severe IVH. There was a significant difference in platelet counts between the IVH and the control group on the first day of life (P=0.046). Presence of IVH was linked with lower birth weight (P=0.006) and lower gestational age (P=0.001). Platelet count on the first day of life was positively correlated with survival (P=0.001) and, along with platelet mass, was indicative of the worst IVH grade recorded for each neonate (P=0.002 and 0.007, respectively). Prolonged prothrombin time was also correlated with IVH (P<0.001), but factor analysis supported no prominent role. Maternal medications seem to play a minor role as well. In conclusion, IVH in extremely premature infants cannot be solely explained by platelet parameters, and further studies are required to determine the relationships between IVH, platelet indices, and outcomes.

Effects of indomethacin prophylaxis timing on intraventricular haemorrhage and patent ductus arteriosus in extremely low birth weight infants

OBJECTIVE

Indomethacin prophylaxis (IP) reduces the risk of intraventricular haemorrhage (IVH) and patent ductus arteriosus (PDA) in preterm infants. However, the optimal time to administer IP has not been determined. We hypothesised that IP at ≤6 h is associated with a lower incidence of IVH or death than if administered at >6-24 h of age.

METHODS

We performed a retrospective cohort study of extremely low birth weight infants (≤1000 g birth weight) treated in the neonatal intensive care units in the Neonatal Research Network from 2003 to 2010 and who received IP in the first 24 h of age. Infants were dichotomised based upon receipt of IP at ≤6 or >6-24 h of age. The primary outcomes were IVH alone and IVH or death. Secondary outcomes were PDA alone and PDA or death. We used multivariable analyses to determine associations between the age of IP and the study outcomes expressed as an OR and 95% CI.

RESULTS

IP was given at ≤6 h to 2340 infants and at >6-24 h to 1915 infants. Infants given IP at ≤6 h had more antenatal steroid exposure, more inborn and less cardiopulmonary resuscitation (p<0.01). After multivariable analyses, age of IP receipt was not associated with IVH, and IVH or death but PDA receiving treatment/ligation or death was lower among IP at ≤6 h compared with IP at >6-24 h (OR 0.83, 95% CI 0.71 to 0.98).

CONCLUSIONS

IP at ≤6 h of age is not associated with less IVH or death, but is associated with less PDA receiving treatment/ligation or death.

Cellular and humoral coagulation profiles and occurrence of IVH in VLBW and ELWB infants

BACKGROUND AND STUDY PURPOSE

Intraventricular hemorrhage (IVH) is a major complication in preterm neonates with significant long-term morbidity and an increased mortality rate. The role of the immature coagulation system in the pathogenesis of IVH in these infants is still under debate. The aim of this study was to provide reference values for coagulation studies within the first 24h of life, and to relate these findings to the incidence of IVH.

PATIENTS AND METHODS

In this retrospective study, a total of 250 (male: 123/female: 127; VLBW: 150 and ELBW: 100) infants were included over a 4-year-period. Coagulation studies were performed within the first 24h of life in all infants. Multiple regression analysis was employed to demonstrate a potential association between IVH and a number of known risk and protective factors for IVH (antenatal steroids, birth weight, gender, IUGR, APGAR score at 10minutes, platelet count, INR, PTT, fibrinogen).

RESULTS

Mean birth weight was 1047.9±305.6 (range: 320-1490g). Both cellular (platelets, nucleated red blood cells) and plasmatic coagulation parameters (INR, fibrinogen and antithrombin III) were dependent on birth weight. Moreover, INR levels (p<0.05) were significantly increased in neonates with IVH of any grade. Also, INR was positively correlated with the severity of IVH (Spearman's correlation coefficient: 0.193; p=0.003). While overall fibrinogen levels were not associated with IVH, a fibrinogen level<100mg/dL significantly increased the risk for IVH (p<0.01).

CONCLUSIONS

Our data provide a robust set of reference values for both cellular and humoral coagulation studies in VLBW and ELBW infants for the first 24h of life. The results of our study indicate that abnormal INR levels and fibrinogen levels<100mg/dL are significantly associated with the occurrence of IVH in this susceptible cohort.