Neonatal thrombosis and its treatment

Symptomatic aortic thrombosis in a preterm neonate

Symptomatic aortic thrombosis is a devastating condition in the neonatal intensive care unit (NICU), which is now increasingly being diagnosed with the availability of bedside ultrasound. Early intervention can go a long way towards preventing adverse outcomes. In our case, a preterm, very low birth weight, growth-restricted baby developed aortic thrombosis with hypertensive emergency and later limb-threatening ischaemia, which usually requires thrombolysis. However, due to the parents' reservations, he was given only therapeutic anticoagulation (with closely monitored activated partial thromboplastin time targets), which resulted in complete thrombus resolution. A multidisciplinary team approach was followed, and early detection with frequent monitoring led us to a favourable outcome.

Evaluation of Patients with Neonatal Thrombosis

The aim of the study is to characterize acquired and genetic risk factors and to give an account of the hereditary thrombophilia panel in neonatal thrombosis. All newborns diagnosed with neonatal thrombosis in a level III NICU were included in this retrospective cohort study. A total of 1850 patients were admitted to the NICU during the 5-y period; and 11 patients were diagnosed with thrombosis (0.58%). The most common risk factors were central venous catheter placement, hypoxia and prematurity and related complications, and sepsis. Four patients were investigated regarding the inherited risk factors for thrombosis. In these 4 patients, homozygous A1298C alleles of MTHFR and heterozygous FXIIIV34L mutations; homozygous PAI-SERPINE1 and heterozygous MTHFRA1298C mutations; compound heterozygous mutations of MTHFRC677T and MTHFRA1298C; and compound heterozygous mutations of MTHFRC677T, MTHFRA1298C, and PAISERPINE1 were detected respectively. In conclusion, neonatal thrombosis is multifactorial; newborns with acquired risk factors may also have hereditary risk factors. TRIAL INFORMATION: ClinicalTrials.govIdentifier: NCT05367466.

Intracardiac Thrombi in Preterm Infants-A Case Study and Review of the Literature

Intracardiac thrombi in preterm infants are not common but may lead to fatal outcomes. Predisposing and risk factors include small vessel size, hemodynamic instability, immaturity of the fibrinolytic system, indwelling central catheters and sepsis. In this paper, we present our own experience with a case of a catheter-related right atrial thrombus in a preterm infant, which was successfully treated with an aspiration thrombectomy. Then, we review the literature on intracardiac thrombosis in preterm infants: epidemiology, pathophysiology, clinical signs, echocardiographic diagnostic features and treatment options are discussed.

Case Report of a Massive Life-threatening Neonatal Thrombosis Treated With a Targeted, Goal-oriented Scheme of Urokinase

BACKGROUND

Thrombotic events are severe, often under-diagnosed, complications occurring in newborn infants during their hospital stay. Currently, there is no consensus regarding the optimal treatment scheme for thrombolysis in neonates.

OBSERVATIONS

We present the case of a newborn suffering from a life-threatening thrombosis. Diagnosis was suggested by a gradual increase of C-reactive protein, with repeatedly normal procalcitonin. Thrombosis was successfully and safely treated with a long scheme of 21 days of urokinase, supported by vascular ultrasound and d-dimer trend.

CONCLUSIONS

Laboratory and ultrasound results may help in adjusting the duration of the thrombolytic treatment, allowing for longer therapeutic schemes that could optimize treatment success. In addition, our case may suggest a possible combined role of C-reactive protein and procalcitonin as an early diagnostic aid in neonatal thrombosis.

Use of thrombolytic agents to treat neonatal thrombosis in clinical practice

Among children, neonates have the highest incidence of thrombosis. Thrombolytic agents are used for the management of life and/or organ-threatening thrombosis. Literature on the efficacy and safety of thrombolytic agents in neonates is limited. We reviewed the evidence on dosing, administration, monitoring and treatment duration of tissue plasminogen activator (tPA), streptokinase and urokinase (URK) in neonates (≤ 28days). A systematic literature search was conducted of current databases from inception until 31 March 2021. The initial search yielded 6881 articles and 18 were retained for review. tPA, streptokinase and URK was utilized in 12, seven and four studies on 115, 51 and 16 patients, respectively. The dose range for tPA, streptokinase and URK was 0.01 -0.6 mg/kg/h, 50-2000 and 1000-0 000 units/kg/h, respectively, and treatment duration ranged from 30 min to 30 days. This is the first study to objectively summarize the efficacy and safety of thrombolytic agents in neonates. Overall, thrombolysis was associated with 87.9% complete or partial thrombus resolution and 7.4% recurrence risk. The bleeding risk associated with thrombolytic agents was 23.1% on pooled analysis, which is higher than other anticoagulants. Larger prospective studies are required to determine effective dosing regimens of these therapeutic drugs and further clarify their efficacy and safety. Blood Coagul Fibrinolysis 33:000-000 Copyright © 2022 Wolters Kluwer Health, Inc. All rights reserved.

Pentoxifylline in the treatment of neonatal vasospasm and thromboembolism: An observational case series study

WHAT IS KNOWN AND OBJECTIVE

Newborns, particularly preterm babies, are prone to vascular vasospasm and thromboembolism. Differences in the haemostatic system, small vessel diameter and presence of any serious diseases are predisposing causes of thromboembolic disease in newborns. The lack of randomized controlled studies on the management of vasospasm and thromboembolism exacerbates the problem. We present a case series of the successful and safe use of PTX for the treatment of vasospasm and thrombosis in neonates.

METHODS

The study was conducted in the Bezmialem Vakif University Hospital Neonatal Intensive Care Unit (NICU). A retrospective chart review was performed on consecutive patients treated for vascular spasm and thrombosis. Nine patients diagnosed with vasospasm or thrombosis were enrolled in the study.

RESULTS

Five patients had arterial injuries. Six patients were premature, and five patients were diagnosed with thrombosis by using Doppler ultrasonography (US). The drug was diluted with 5% dextrose and administered intravenously at a dose of 5 mg/kg/h over six hours, ranging from 1 to 5 days. No drug-related side effects were observed. All babies recovered, and no amputation was performed.

WHAT IS NEW AND CONCLUSION

PTX may be an alternative treatment for vascular vasospasm and thromboembolism with fewer side effects than anticoagulant and thrombolytic agents in neonates. Starting PTX in the early stages of vascular insult may prevent the development of vasospasm and thromboembolism and thus limb ischaemia.

Lower-Limb Ischemia at Birth Because of Spontaneous Arterial Thrombosis: A Case Report

CASE

A full-term neonate presented with right lower extremity ischemia at birth because of spontaneous thrombosis of the right common iliac artery. He was initially managed with supportive treatment, anticoagulation, and dressings; however, advanced gangrenous changes precluded salvage of the ischemic limb. A guillotine amputation was performed at day 15 of life, and the stump went on to heal well by secondary intention.

CONCLUSION

Thromboembolic events occurring in infancy are well-recognized phenomena; however, it is far rarer to encounter a neonate born with "congenital gangrene". We discuss the etiology, approach to diagnosis, and treatment of this rare but devastating condition.

Abdominal aortic thrombus formation in a neonate with an interrupted aortic arch

We note the risk of paradoxical embolism in patients with congenital heart defects with a right-to-left shunt. These patients should be managed to ensure that abdominal aortic thrombi are not overlooked when their clinical conditions change.

Catheter-related venous thrombosis in NICU: A case-control retrospective study

INTRODUCTION

Newborns treated in a neonatal intensive care unit (NICU) are susceptible to several complications one of them being vein thrombosis.

AIM

The study aims to evaluate risk factors of catheter-related venous thrombosis, clinical manifestations, treatment, and the outcomes of thrombotic events (TE) during the neonatal period.

METHODS

This work is a case-control retrospective study performed on patients in the tertiary NICU between January 2013 and June 2016. The analysis includes data from infants with CVC diagnosed with thrombosis and infants with CVC, not being diagnosed with thrombosis (control group). Statistica 10 software was used for statistical analysis.

RESULTS

Vein thrombosis was diagnosed in 19 NICU infants including 16 cases of catheter-related vein thrombosis (84% of complicated cases). Other statistically significant risk factors were asphyxia, infection, and the duration of CVC use. The incidence of thrombosis in our population increased during the study which may result from a statistically significant increase in the number of inserted CVC (294 vs 435), and more frequent diagnosis of incidental thrombosis (1 vs 9).

CONCLUSION

Vein catheterization, asphyxia, infection, and prolonged CVC use are critical risk factors for thrombosis in the neonatal period. Given the hereinbefore mentioned increased number of central line catheterizations in the NICU, it would be useful to conduct a prospective study with a scheduled routine ultrasound protocol applied not only as a tool to diagnose thrombosis but also to prevent it by determining a proper catheter for a particular vein.

Emerging predictors of femoral artery occlusion after pediatric cardiac catheterization

The Objective was to review the prevalence of femoral artery occlusion (FAO) after cardiac catheterization in children up to 12 years old from two centers in China and identify its related risk factors. After collecting clinical data from patients who had undergone pediatric cardiac catheterization, univariate and multivariate analysis were used to evaluate the correlations between FAO and clinical factors, including sex, age, height, weight, sheath size, operation time, therapeutic strategy, sheath/age, sheath/height and sheath/weight. The ROC curve was also used to assess the influence of risk factors to predict FAO. FAO occurred in 19 (0.9%) out of 2,084 children following cardiac catheterization. Patients with younger age, lower height, longer operation time, electrophysiological (EP) diagnosis or/and therapy for arrhythmias, higher Sheath/Age, higher Sheath/Height and higher Sheath/Weight ratios had higher risk for FAO compared to their respective control groups (p < 0.05). In the multivariate analysis, sheath/age and operation time were independent risk factors for FAO. Patients with operation time > 77.5 min or sheath/age > 0.5334 had a significantly higher risk for FAO. Operation time and sheath/age were confirmed as significant and independent risk factors associated with FAO. Operation time > 77.5 min and sheath/age > 0.5334 could effectively predict high risk of FAO after pediatric cardiac catheterization.

Fibrinolytic therapy in newborns with superior vena cava syndrome. Case report

Introduction: Superior vena cava syndrome is described as the obstruction of blood flow through the superior vena cava. The literature reports that the incidence of this pathology varies from 1 case in every 650 inhabitants and 1 case in every 3 100 inhabitants. Since this condition is very rare in the pediatric population, no clear figure has been reported regarding its incidence in children. The use of a central venous catheter in newborns is a risk factor for this condition, as it may cause a thrombus due to the inflammatory reaction against the device. Therefore, it is necessary to initiate anticoagulation management and remove the catheter.Case presentation: Premature male newborn, (31.4 weeks gestation), with acute respiratory distress syndrome, early neonatal sepsis, pneumonia, necrotizing enterocolitis on 2 occasions, intestinal obstruction due to adhesions and intestinal volvulus. At 90 days of age, he presented thrombosis of the superior vena cava without involvement of the jugular and subclavian vein junction in the right atrium. Anticoagulant management was started, but given his unfavorable evolution, a multidisciplinary medical board was held to assess the risks, benefits, and treatment options in this age group. It was decided to start intracavitary tissue plasminogen activator treatment associated with mechanical thrombectomy and angioplasty of the superior vena cava. Due to the difficulty of conducting clinical trials in this population and the rates of major bleeding complications obtained with thrombolytic therapies, there is very little information available on the use of tissue plasminogen activator in newborns. For this reason, alteplase is seldom considered as the therapy of choice. However, in patients with life-threatening thrombosis, such as the present case, the results obtained in adults could be extrapolated in search of a favorable outcome.Conclusions: Fibrinolytic therapy is a way to reduce the size of the thrombus, but it dramatically increases the risk of bleeding; consequently, these patients must be strictly monitored. In pediatric populations, due to the diameter of the blood vessels, thrombectomy is difficult to perform; additionally, recurrent thrombosis and the need for transfusion of blood products are frequent.

Epidemiology of thrombosis in Canadian neonatal intensive care units

OBJECTIVE

To assess the rate, location, risk factors, management, and outcomes of neonatal thrombosis (NT).

DESIGN

A retrospective study investigating infants admitted to NICUs in Canadian Neonatal Network between January 2014 and December 2016 and diagnosed with NT. Each infant with NT was matched with an infant without NT.

RESULTS

Of 39,971 infants, 587 (1.5%) were diagnosed with NT: 440 (75%) venous, 112 (19%) arterial, 29 (5%) both. NT rate was 1.4% in full-term and 1.7% in preterm infants. Venous thrombi occurred most commonly in the portal vein and arterial thrombi in the cerebral artery. Conservative management and low molecular weight heparin were the most common treatment modalities. Hospital stay was longer (p < 0.001) in the NT patients, but mortality was similar.

CONCLUSIONS

NT was diagnosed in ~15/1000 NICU admissions and most commonly in the portal vein and cerebral arteries. Management varied based on the type and location of thrombi. Large multicenter trials are needed to address the best management strategies.

Spontaneous aortic thrombosis in neonates: a case report and review of literature

Neonatal aortic thrombosis is a rare occurrence but can be life-threatening. Most aortic thrombosis in neonates is related to umbilical artery catheters. A case of a neonate with a spontaneous aortic thrombosis is described here along with a comprehensive review of the literature for cases of neonatal aortic thrombosis not related to any intravascular device or procedure. The aetiologies of these spontaneous thromboses and the relevance of hypercoagulable disorders are discussed. The cases were analysed for odds of death by treatment method adjusted for era. The reference treatment method was thrombolysis and anticoagulation. No other treatment modality had significantly lower odds than the reference. Surgery alone had higher odds for death than the reference, but this may be confounded by severity of case. The management recommendations for clinicians encountering neonates with spontaneous neonatal aortic thrombosis are discussed.

Respiratory failure secondary to congenital pulmonary arterial thrombus with lung dysplasia

Respiratory failure requiring extracorporeal membranous oxygenation in the newborn is commonly seen secondary to severe pathology such as congenital diaphragmatic hernia, meconium aspiration syndrome, pulmonary hypertension and pulmonary hypoplasia. However, atypical causes of respiratory failure, such as pulmonary arterial thrombi, are often refractory to traditional management and require careful multidisciplinary evaluation. We report a case of respiratory failure secondary to congenital pulmonary arterial thrombosis of unknown aetiology in an otherwise healthy neonate. We discuss the abnormal anatomy and pathophysiology that presented in our patient secondary to this condition and discuss our diagnostic process, management and outcomes. Additionally, we review the literature for reported cases and discuss current hypotheses on the development of congenital pulmonary arterial thrombi. Given the rare occurrence of this event, we hope to contribute to the understanding of future similar cases and emphasise the importance of keeping pulmonary arterial thrombi in the clinical differential.

Incidence and features of thrombosis in children with inherited antithrombin deficiency

Pediatric thromboembolism (≤18 years) is very rare (0.07-0.14/10,000/year) but may be more prevalent in children with severe thrombophilia (protein C, protein S or antithrombin deficiency). The aim of this study was to define the prevalence and clinical characteristics of pediatric thrombosis in subjects with inherited antithrombin deficiency. Our observational retrospective multicentric study from two countries recruited 968 patients of any age from 441 unrelated families with genetically, biochemically and functionally characterized antithrombin deficiency. Seventy-three subjects (7.5%) developed thrombosis before 19 years of age. Two high-risk periods for thrombosis were identified: adolescence (12-18 years, n=49) with thrombus localization (lower limb deep venous thrombosis or pulmonary embolism) and triggering factors common to adults (oral contraceptives, surgery or pregnancy); and the neonatal period (<30 days, n=15) with idiopathic thrombosis at unusual sites. The clinical evaluation of pediatric thrombosis in subjects with antithrombin deficiency revealed: i) a high prevalence of cerebral sinovenous thrombosis (n=13, 17.8%), mainly at young age (8 neonates and 4 children <6 years); ii) severe outcome with fatality in six cases (3 neonates, two of them homozygous for p.Leu131Phe). The majority of subjects (76.7%) carried quantitative type I deficiency. This retrospective analysis includes the largest cohort of subjects with inherited antithrombin deficiency so far and provides strong evidence for an increased risk of pediatric thrombosis associated with this thrombophilia (300-fold compared with the general population: 0.41%/year vs. 0.0014%/year, respectively). Our results support testing for antithrombin deficiency in children of affected families, particularly in case of type I deficiency.

Effectiveness and Safety of 4-factor Prothrombin Complex Concentrate (4PCC) in Neonates With Intractable Bleeding or Severe Coagulation Disturbances: A Retrospective Study of 37 Cases

BACKGROUND

To date, clinical experience with prothrombin complex concentrate (PCC) in the neonatal population has been limited.

AIM

The objective of this study was to describe our experience regarding the effectiveness and safety of PCC administration in newborns with severe bleeding or coagulopathy resistant to conventional therapy.

METHODOLOGY

We retrospectively analyzed data from 37 neonates with intractable bleeding or severe coagulation disturbances. All patients received intravenous bolus administration of 20 or 30 u/kg of PCC per dose, as a rescue procedure.

RESULTS

Hemostasis was achieved in the majority of neonates and we observed statistically significant improvement in prothrombin time, international normalized ratio, and activated partial thromboplastin time (P<0.001, P=0.044, P<0.001, respectively). Thirteen neonates survived, whereas 24 did not survive. In those who survived, PCC had been administered earlier (<24 h) in the disease process compared with those who died (P=0.043). Neither acute adverse events nor thromboembolic complications were observed in all neonates.

CONCLUSIONS

In our study, PCC seemed to be a safe and effective intervention for hemostasis and early intervention was more effective as a rescue therapy, without any adverse event. Further prospective controlled trials are required to determine optimal dose and timing of PCC administration in neonates.

Management of Extremity Venous Thrombosis in Neonates and Infants: An Experience From a Resource Challenged Setting

We aimed to evaluate the outcome of different treatment modalities for extremity venous thrombosis (VT) in neonates and infants, highlighting the current debate on their best tool of management. This retrospective study took place over a 9-year period from January 2009 to December 2017. All treated patients were referred to the vascular and pediatric surgery departments from the neonatal intensive care unit. All patients underwent a thorough history-taking as well as general clinical and local examination of the affected limb. Patients were divided into 2 groups: group I included those who underwent a conservative treated with the sole administration of unfractionated heparin (UFH), whereas group II included those who were treated with UFH plus warfarin. Sixty-three patients were included in this study. They were 36 males and 27 females. Their age ranged from 3 to 302 days. Forty-one (65%) patients had VT in the upper limb, whereas the remaining 22 (35%) had lower extremity VT. The success rate of the nonsurgical treatment was accomplished in 81% of patients. The remaining 19% underwent limb severing, due to established gangrene. The Kaplan-Meier survival method revealed a highly significant increase in both mean and median survival times in those groups treated with heparin and warfarin compared to heparin-only group ( P < .001). Nonoperative treatment with anticoagulation or observation (ie, wait-and-see policy) alone may be an easily applicable, effective, and a safe modality for management of VT in neonates and infants, especially in developing countries with poor or highly challenged resource settings.

Experience and Prognosis of Systemic Neonatal Thrombosis at a Level III NICU

OBJECTIVE

The objective of this article was to evaluate neonates diagnosed systemic thrombosis and their outcomes.

METHODS

We retrospectively evaluated data of neonatal systemic thrombosis between January 2011 and December 2016.

RESULTS

Among 4376 hospitalized, 30 neonates (0.69%) were diagnosed systemic thrombosis. Their mean birth weight was 2422±1152 g (680 to 4750 g), gestational age was 35±5.4 weeks (25 to 41 wk). There were 25 neonates (83.3%) with venous, 5 patients (16.7%) with arterial thrombosis. The most common sites that thrombi localized were major vessels (n=11) and central nervous system (n=8). Central catheter insertion (76.7%) and prematurity (46.7%) were the most common risk factors. Congenital prothrombotic risk factors included G1691A mutation in factor V Leiden (n=1), mutation in factor XIII (n=1), C677T mutation in methylenetetrahydrofolate reductase (n=6). More than 1 congenital risk factor was identified in 5 patients. The patients were treated with low-molecular weight heparin. The mortality rate was 13.3% (n=4). Two patients required amputation (left foot, left upper extremity). Unilateral renal atrophy (n=1), cerebral palsy (n=2), hemiparesis (n=1) were identified among followed 24 patients.

CONCLUSIONS

Critically ill neonates are at risk for thrombosis, and devastating consequences can result. As indwelling catheters and prematurity are important, careful monitorization, early diagnosis and therapy, cautious care of central catheter might reduce the incidence and adverse outcome.

Risk Factors for Neonatal Venous and Arterial Thromboembolism in the Neonatal Intensive Care Unit-A Case Control Study

OBJECTIVE

To identify risk factors associated with venous and arterial thrombosis in sick neonates admitted to the neonatal intensive care unit.

STUDY DESIGN

A case-control study was conducted at 2 centers between January 2010 and March 2014 using the Children's Hospital Neonatal Database dataset. Cases were neonates diagnosed with either arterial or venous thrombosis during their neonatal intensive care unit stay; controls were matched in a 1:4 ratio by gestational age and presence or absence of central access devices. Bivariable and conditional logistic regression analyses for venous and arterial thrombosis were performed separately.

RESULTS

The overall incidence of neonatal thrombosis was 15.0 per 1000 admissions. A higher proportion of neonates with thrombosis had presence of central vascular access devices (75% vs 49%; P < .01) were of extremely preterm gestational age (22-27 weeks; 26% vs 15.0%; P <.05) and stayed ≥31 days in the neonatal intensive care unit (53% vs 32.9%; P <.01), when compared with neonates without thrombosis. A final group of 64 eligible patients with thrombosis and 4623 controls were analyzed. In a conditional multivariable logistic regression model, venous thrombosis was significantly associated with male sex (AOR, 2.12; 95% CI, 1.03-4.35; P = .04) and blood stream infection (AOR, 3.47; 95% CI, 1.30-9.24; P = .01).

CONCLUSIONS

The incidence of thrombosis was higher in our neonatal population than in previous reports. After matching for central vascular access device and gestational age, male sex and blood stream infection represent independent risk factors of neonatal venous thrombosis. A larger cohort gleaned from multicenter data should be used to confirm the study results and to develop thrombosis prevention strategies.

[Spontaneous neonatal aortic thrombosis revealing protein S deficiency]

Arterial thrombosis of the newborn is rare and associated with poor prognosis, often attributed to umbilical arterial catheterization. The aortic and spontaneous forms are exceptional. Its severity requires fast and effective treatment. Although therapeutic means are numerous, no consensus has been established to date although thrombolysis and heparin therapy appear to give good results depending on the site and extent of thrombosis. We report a case of extensive thrombosis of the abdominal aorta in a 5-day-old newborn, revealed by acute hypernatremic dehydration. Thrombosis was not related to umbilical catheterization. The diagnosis was confirmed by Doppler ultrasound with discovery during the etiologic assessment of an authentic protein S deficiency. This observation was the occasion for a review of the literature concerning the evolutionary and therapeutic clinical aspects of neonatal arterial thrombosis.

Neonatal Venous Thromboembolism

Neonates are the pediatric population at highest risk for development of venous thromboembolism (VTE), and the incidence of VTE in the neonatal population is increasing. This is especially true in the critically ill population. Several large studies indicate that the incidence of neonatal VTE is up almost threefold in the last two decades. Central lines, fluid fluctuations, sepsis, liver dysfunction, and inflammation contribute to the risk profile for VTE development in ill neonates. In addition, the neonatal hemostatic system is different from that of older children and adults. Platelet function, pro- and anticoagulant proteins concentrations, and fibrinolytic pathway protein concentrations are developmentally regulated and generate a hemostatic homeostasis that is unique to the neonatal time period. The clinical picture of a critically ill neonate combined with the physiologically distinct neonatal hemostatic system easily fulfills the criteria for Virchow's triad with venous stasis, hypercoagulability, and endothelial injury and puts the neonatal patient at risk for VTE development. The presentation of a VTE in a neonate is similar to that of older children or adults and is dependent upon location of the VTE. Ultrasound is the most common diagnostic tool employed in identifying neonatal VTE, but relatively small vessels of the neonate as well as frequent low pulse pressure can make ultrasound less reliable. The diagnosis of a thrombophilic disorder in the neonatal population is unlikely to change management or outcome, and the role of thrombophilia testing in this population requires further study. Treatment of neonatal VTE is aimed at reducing VTE-associated morbidity and mortality. Recommendations for treating, though, cannot be extrapolated from guidelines for older children or adults. Neonates are at risk for bleeding complications, particularly younger neonates with more fragile intracranial vessels. Developmental alterations in the coagulation proteins as well as unique pharmacokinetics must also be taken into consideration when recommending VTE treatment. In this review, epidemiology of neonatal VTE, pathophysiology of neonatal VTE with particular attention to the developmental hemostatic system, diagnostic evaluations of neonatal VTE, and treatment guidelines for neonatal VTE will be reviewed.

Neonatal Hematologic Disorders

Neonatal hematology is a complex subspecialty of pediatric hematology, combining the unique aspects of the maternal/fetal relationship, the delicate balance of coagulation factors, and the distinctive physiologic conditions of the newborn period. The objective of this article is to briefly review specific hematologic disorders that commonly present in the newborn period. Alloimmune cytopenias, polycythemia, thrombosis and bleeding associated with vitamin K deficiency will be discussed through a focus on pathophysiology, signs and symptoms, current treatment strategies, and implications for nursing care.

Thromboembolism and anticoagulation management in the preterm infant

The incidence of preterm thromboembolism has been increasing due to advances in diagnostic imaging which allow better detection of thrombi in sick preterm infants. At the same time, improvement in neonatal intensive care unit supportive care has increased the number of surviving and living preterm infants with thromboembolic risk factors. Disruption in the fine balance of hemostasis with potential risk factors, specifically septicemia and indwelling catheters, increase the occurrence of thromboembolic events. Treatment strategies in preterm infants are challenging due to limited data.

Acute forearm compartment syndrome in a newborn caused by reperfusion after spontaneous axillary artery thrombosis

Acute compartment syndrome of the forearm in newborns is often misdiagnosed and can be disastrous if left untreated. Here, we report a full-term infant of a diabetic mother with underlying heterozygosity for MTHFR C677T and A1298C alleles. A spontaneous thrombosis occurred in the left axillary artery immediately after birth. The patient responded well to anticoagulant (heparin) and thrombolytic (tissue plasminogen activator) agents. After reperfusion of the extremity, acute compartment syndrome developed. Emergent fasciotomy was performed. In this case, effective collaboration between pediatricians and orthopedic surgeons resulted in salvage of the extremity, with good clinical and functional results.

Thrombosis in the Neonatal Intensive Care Unit

Neonates have the highest risk for pathologic thrombosis among pediatric patients. A combination of genetic and acquired risk factors significantly contributes to this risk, with the most important risk factor being the use of central venous catheters. Proper imaging is critical for confirming the diagnosis. Despite a significant number of these events being life- and limb-threatening, there is limited evidence on what the appropriate management strategy should be. Evaluation and treatment of any neonate with a clinically significant thrombosis should occur at a tertiary referral center that has proper support.

Prenatal Diagnosis of A Case with Frontoethmoidal Encephalocele and the Neonatal Outcome

Encephalocele is a rare congenital defect characterized by a sac-like protrusion of the neural tissue and/or meninges through a defect in the skull. We reported a case with a naso-frontal anterior encephalocele which was diagnosed by prenatally and confirmed by postnatal evaluation and complications such as hypoadrenalism, diabetes insipidus and arterial thrombosis in the lower limbs were diagnosed in the neonatal period.

Neonatal haemostasis and the management of neonatal thrombosis

Two detailed reviews of the management of neonatal thrombosis were published in 2012; one was an up-dated version of guidance first issued in 2004 and the other was a comprehensive review. Both of these publications gave very similar advice regarding the practical aspects of the indications, dosage and management of antithrombotic therapy. The authors stated that the evidence supporting most of their recommendations for anti-thrombotic therapy in neonates remained weak and so the therapy for a neonate with a thrombosis has to be based on an individualized assessment of estimated risk versus potential benefit. The aim of this present review is to give the treating physician an outline of the unique physiology of neonatal coagulation and how this affects the monitoring, dosing and even the choice of therapeutic strategy for the management of thrombosis in the neonate.

Axillary artery thrombosis in a neonate in utero: a case report

We describe a neonate of 38-week and 6-day gestation born by lower uterine cesarean section for breech presentation, where it was evident on delivery that there was significant edema of the right arm from the deltoid to the distal tips of the fingers. Doppler flow ultrasound revealed extensive arterial thromboembolus. Intravenous heparin was prescribed for three days at a dose of 27.5 U/kg/h, targeting an activated partial thromboplastin time (APTT) of 60–75 seconds, followed by a course of subcutaneous enoxaparin at a dose of 1.8 mg/kg and then 2 mg/kg twice daily, titrated to a factor Xa level of 0.5–1.0 U/mL for another three days. Significant clinical improvement occurred and the child was eventually, discharged on subcutaneous enoxaparin. Magnetic resonance imaging showed multiple intracranial abnormalities. At five months increased upper limb tone, brisk reflexes, and small head circumference were noted. At one year, increased tone and increased paucity of movement on the right side persisted, and some speech delay and visual inattention were noted. Recent follow-up at 16.5 months of age demonstrated a right sided hemiplegia with increased tone and brisk reflexes. We describe the case in detail and review current knowledge regarding the management of arterial thrombosis in the neonate.

Routine surveillance ultrasound for the management of central venous catheters in neonates

OBJECTIVES

To evaluate the frequency of central venous catheter (CVC)-related thrombi detected by routine surveillance ultrasound, and to assess whether positive findings had an impact on management or outcomes.

STUDY DESIGN

All neonates in a tertiary neonatal intensive care unit who had a CVC inserted for >14 days underwent routine surveillance ultrasound biweekly between January 2003 and December 2009. Data were reviewed retrospectively.

RESULTS

Although all neonates were asymptomatic at time of surveillance ultrasound, 645 of the total 1333 CVCs inserted in 1012 neonates underwent surveillance ultrasound, and thrombi were detected in 69 (10.7%). The CVCs with thrombi were more likely to be removed for nonelective reasons compared with CVCs without thrombi (59% vs 38%; P = .001; OR, 2.4, 95% CI 1.4-3.9). A total of 955 surveillance ultrasounds were performed to detect and monitor 69 CVCs with thrombi. The majority of thrombi were nonocclusive and nonprogressive. A change in management occurred in 8 cases of CVC-related thrombi (12%), or 1% of all screened cases. An average of 14 ultrasounds were required to detect and monitor 1 CVC with thrombus, at a cost of $951 per CVC with thrombus and $8106 per case of CVC-related thrombi with a change in treatment.

CONCLUSION

Asymptomatic thrombi were detected in a significant proportion of CVCs by routine surveillance ultrasound. There were significant costs, but infrequent changes to patient management.

Intrauterine upper limb ischemia: an unusual presentation of fetal thrombophilia-a case report and review of the literature

Upper limb ischemia presenting in neonatal period is extremely rare. Moreover, presenting newborn with evidence of intrauterine upper limb vascular occlusion is even rarer. It needs prompt intervention to restore perfusion and avoid morbidity. We present a newborn with right upper limb brachial artery thrombosis causing ischemia that was noted at birth and appeared later to be homozygous for factor V Leiden and glycoprotein IIIa with no other identifiable risk factors. In this report, we present the case, its successful medical management, proper counseling, and review of the literature. We recommend investigating the neonates and their parents for thrombophilia mutations when they present with unusual vascular occlusion site as newborns.

Neonatal ascending aortic thrombus: successful medical treatment

Neonatal aortic thrombosis is a potentially life-threatening condition with significant morbidity and mortality if undiagnosed and untreated. The most common location of arterial thrombosis in neonates is in the abdominal aorta and is associated with umbilical artery catheterisation. There are only a few previous reports of thrombosis in the ascending aorta. We describe a case of ascending aortic thrombosis in a neonate who underwent successful thrombolytic therapy.

Superior vena cava syndrome causing chylothoraces in a preterm neonate: a case report and literature review

A preterm neonate developed catheter-related central venous and dural sinus thrombosis. Superior vena cava (SVC) obstruction caused significant bilateral chylothoraces and SVC thrombotic obstruction led to generalized anasarca and multiple organ failure. Six weeks after the diagnosis of SVC and sagittal sinus occlusion and chylothoraces, the infant expired. We report a rare case of a chylothoraces secondary to SVC obstruction, and superior sagittal sinus thrombosis in a preterm neonate, and review the literature.

Antithrombotic therapy in neonates and children: Antithrombotic Therapy and Prevention of Thrombosis, 9th ed: American College of Chest Physicians Evidence-Based Clinical Practice Guidelines

BACKGROUND

Neonates and children differ from adults in physiology, pharmacologic responses to drugs, epidemiology, and long-term consequences of thrombosis. This guideline addresses optimal strategies for the management of thrombosis in neonates and children.

METHODS

The methods of this guideline follow those described in the Methodology for the Development of Antithrombotic Therapy and Prevention of Thrombosis Guidelines: Antithrombotic Therapy and Prevention of Thrombosis, 9th ed: American College of Chest Physicians Evidence-Based Clinical Practice Guidelines.

RESULTS

We suggest that where possible, pediatric hematologists with experience in thromboembolism manage pediatric patients with thromboembolism (Grade 2C). When this is not possible, we suggest a combination of a neonatologist/pediatrician and adult hematologist supported by consultation with an experienced pediatric hematologist (Grade 2C). We suggest that therapeutic unfractionated heparin in children is titrated to achieve a target anti-Xa range of 0.35 to 0.7 units/mL or an activated partial thromboplastin time range that correlates to this anti-Xa range or to a protamine titration range of 0.2 to 0.4 units/mL (Grade 2C). For neonates and children receiving either daily or bid therapeutic low-molecular-weight heparin, we suggest that the drug be monitored to a target range of 0.5 to 1.0 units/mL in a sample taken 4 to 6 h after subcutaneous injection or, alternatively, 0.5 to 0.8 units/mL in a sample taken 2 to 6 h after subcutaneous injection (Grade 2C).

CONCLUSIONS

The evidence supporting most recommendations for antithrombotic therapy in neonates and children remains weak. Studies addressing appropriate drug target ranges and monitoring requirements are urgently required in addition to site- and clinical situation-specific thrombosis management strategies.

Management of neonatal thrombosis

Neonates have one of the highest risks for thromboembolism among pediatric patients. This risk is attributable to a combination of multiple genetic and acquired risk factors. Despite a significant number of these events being either life threatening or limb threatening, there is limited evidence on appropriate management strategy. Most of what is recommended is based on uncontrolled studies, case series, or expert opinion. This review begins with a discussion of the neonatal hemostatic system, focusing on the common sites and imaging modalities for the detection of neonatal thrombosis. Perinatal and postnatal risk factors are presented and management options discussed.

Incidence and predictors of indwelling arterial catheter-related thrombosis in children

BACKGROUND

 Indwelling arterial catheters (IACs) are used for monitoring and blood sampling purposes in intensive care units. Very limited information is available on the incidence and risk factors of IAC-related thrombosis in children.

OBJECTIVE

 To investigate the incidence and predictors of IAC-related thrombosis in a tertiary care pediatric hospital.

METHODS

  For a period of 12 months, detailed information was prospectively recorded for all consecutive children requiring IACs.

RESULTS

 Six hundred and fifteen IACs were placed in a total of 473 children at a median age of 0.56 years for a total of 47440.84 catheter hours. Of the 615 IACs, 418 (68%) were placed in the radial artery, 137 (22%) in the femoral artery, 26 (4%) in the umbilical artery, 11 (2%) in the brachial artery, and 23 (3.7%) in another artery. Thrombosis occurred in 20 cases, reflecting an overall incidence of 3.25%. Eighteen of the 20 IAC-related thrombi were located in the femoral arteries, reflecting a relative incidence of 13% (18/137). Newborn age, lower body weight, low cardiac output and increased hematocrit were significantly related with an increased risk of femoral artery thrombosis. In logistic regression analysis, younger age (P<0.001, odds ratio 6.51) was independently associated with an increased thrombotic risk.

CONCLUSIONS

 This study demonstrates that arterial thrombosis occurs with an increased incidence in children requiring IACs in the femoral location. Younger age is independently associated with an increased risk of thrombosis. The radial location is safe, and should be preferred to the femoral location.

A neonate with left pulmonary artery thrombosis and left lung hypoplasia: a case report

INTRODUCTION

Spontaneous intrauterine arterial thrombosis and congenital pulmonary hypoplasia are rare conditions and have not been reported to occur together. The literature rather includes two reports of babies with neonatal pulmonary artery occlusion and post-infarction cysts of the lungs.

CASE PRESENTATION

We report a case of a live Caucasian male newborn with left lung hypoplasia that occurred in association with left pulmonary artery thrombosis. Despite a critical neonatal course, including extracorporeal membrane oxygenation, this infant is alive and well at 18 months of age without any neurodevelopmental sequelae or reactive airway disease.

CONCLUSION

This association suggests the possibility of an intrauterine vascular event between the fifth and eighth weeks of gestation during early pulmonary artery and lung development.

Neonatal thrombo-embolism: risk factors, clinical features and outcome

BACKGROUND

There are few data with respect to prothrombotic risk factors in neonates.

AIM

To determine the associated risk factors, clinical features and outcome in newborn infants diagnosed with thrombo-embolism.

METHODS

Case records of 25 infants (17 full-term and eight preterm) diagnosed with thrombo-embolism between January 2005 and April 2008 in a neonatal intensive care unit were reviewed.

RESULTS

Of the 25 infants, 18 cases of venous (72%) and seven of arterial (28%) thrombo-embolism were recorded; in 18 it was associated with central catheterisation. The sites of thrombosis were portal vein (15), right renal vein (one), right femoral vein (one), multiple veins (one), right femoral artery (3), right iliac artery (2), bilateral iliac and renal arteries (one) and left renal artery (one). Hereditary thrombotic mutations were detected in three patients and anticardiolipin antibody was detected in one, none of whom had been catheterised. The remaining three non-catheterised patients had perinatal risk factors. Venous catheter placement was undertaken in 12 patients (48%), eleven of whom had: umbilical venous catheterisation for exchange transfusion (9), partial exchange transfusion (one) and venous access (one), and one had femoral venous catheterisation for an angiographic study. Arterial catheterisation was undertaken in seven patients (28%) (one infant had both umbilical venous and arterial catheters) for angiographic studies (5) and blood sampling (2). Of the 18 catheterised patients (72%), thrombophilic studies were undertaken in 13 and none had abnormal results. Additional perinatal risk factors were present in 18 patients (72%) and included prematurity (8), congenital heart disease (8), septicaemia (5), dehydration (3), respiratory distress syndrome (3), polycythemia (2), meconium aspiration syndrome (one), pneumonia (one), maternal diabetes (one), necrotising enterocolitis (one) and perinatal asphyxia (one). Although most of the patients recovered after anticoagulant or fibrinolytic therapy, the five (20%) deaths were associated mainly with underlying diseases.

CONCLUSION

The most important risk factor for thrombo-embolic events in neonates is placement of central catheters and some perinatal prothrombotic conditions. Nevertheless, hereditary or acquired thrombophilic risk factors may also be a cause of thrombo-embolism.

Occlusive aortic arch thrombus in a preterm neonate

OBJECTIVE

To present the case of an extremely preterm infant with occlusive aortic arch clot managed with low-risk therapy.

DATA SOURCE

Case details were obtained from medical records and echocardiographic images from Excelera database.

STUDY SELECTION

Preterm infant with occlusive clot in the aortic arch.

DATA EXTRACTION AND SYNTHESIS

Demographic details (gestation age and birthweight), clinical and biochemical data (blood pressure, oxygen saturation, urine output, lactate levels, and coagulation profile) were obtained from medical records. A female infant was born at 28 wks gestation and had umbilical catheters inserted in satisfactory positions. On day 6, pre- and postductal oxygen saturation differences, a significantly higher blood pressure on right arm, and weak pulses were noted. Echocardiogram revealed an occlusive thrombus in the aortic arch distal to the innominate artery, extending into the carotid artery with retrograde flow in the left internal carotid and subclavian arteries. The distal aortic circulation was supported by ductus arteriosus shunting bidirectionally. Intravenous prostaglandin E and heparin were started, the latter was later replaced by enoxaparin. Serial echocardiograms over next 3 mos showed complete resolution of the thrombus.

CONCLUSIONS

Neonatal aortic arch thrombus is extremely rare with only 3 cases previously reported--all in term infants. Therapeutic options include anticoagulation, thrombolytic therapy, and thrombectomy. The risk/benefit ratio for anticoagulation and thrombolytic therapy is unknown and must be individualized. This preterm infant was managed with low-risk therapy and had an optimal outcome.