Management of preterm infants with intracardiac thrombi: use of thrombolytic agents

Addressing challenges in pediatric thrombosis: a comprehensive guideline development

Background

Pediatric thrombosis is a relatively rare but severe condition in the field of pediatrics, with far-reaching consequences. Recent studies have indicated a rising incidence of this disease in children over the years. Additionally, the pharmacological treatment of thrombotic diseases in children faces numerous challenges. Due to significant physiological differences between children and adults, guidelines for the prevention and treatment of thrombotic diseases in adults cannot be directly applied to pediatric patients.

Purpose

A systematic review of the existing evidence-based medical literature should be conducted to propose pharmacological prevention and treatment recommendations for pediatric thrombotic diseases. Developing a comprehensive and practical pharmacotherapy guideline for the prevention and treatment of pediatric thrombotic diseases is essential to enhancing the rational use of medications in managing these conditions in children.

Methods

The guideline development followed the World Health Organization's (WHO) Handbook for Guideline Development. This involves systematically searching and extensively collecting data on common medication issues in the prevention and treatment of pediatric thrombosis nationwide. The Delphi method was used to survey experts and identify the clinical issues to be included. Subsequently, a systematic literature review was conducted to evaluate existing primary studies, systematic reviews, and guidelines or consensus statements from professional organizations. The quality of the evidence was assessed using the Grading of Recommendations Assessment, Development and Evaluation (GRADE) approach. The Delphi method was employed again to reach a consensus on the recommendations and evidence levels. This process was culminated in the development of the Guideline for Pharmacological Management of Thrombotic Diseases in Children.

Results

During the guideline development process, a total of 29 clinical issues were collected and evaluated by 78 experts in clinical pharmacy and clinical medicine. Through two rounds of surveys, 13 clinical issues were selected. Under the supervision of two methodologists, 13 clinical pharmacotherapy recommendations were formulated.

Conclusion

By conducting a comprehensive assessment of the feasibility and safety of clinical practices, the guideline provides specific anticoagulant medication recommendations for pediatric healthcare professionals. This will help enhance the prevention and treatment of pediatric thrombosis, promoting more standardized and effective medical practices.

A Case of Enterococcal Patent Ductus Arteriosus-associated Endarteritis in a Preterm Neonate

INTRODUCTION

The persistent patency of the ductus arteriosus frequently occurs in premature neonates and can cause infective endocarditis (IE) or ductal endarteritis (DE) during sepsis. Even though neonatal IE and DE are believed to be a rare eventuality, their incidence has been increasing in the last decades due to the improved survival of even more preterm babies, favored by highly invasive procedures and therapies. In parallel, antimicrobial resistance is another rising problem in neonatal intensive care units, which frequently compels to treat infections with broad-spectrum or last generation antibiotics.

CASE PRESENTATION

We report the case of a preterm neonate affected by patent ductus arteriosus-associated DE that followed an episode of sepsis caused by a high-level aminoglycoside-resistant enterococcus. The neonate was successfully treated with the synergistic combination of ampicillin and cefotaxime.

DISCUSSION

IE and patent ductus arteriosus-associated DE are rising inside neonatal intensive care units and neonatologists should be aware of these conditions. Enterococcal IE and patent ductus arteriosus-associated DE sustained by high-level aminoglycoside-resistant strains can be successfully treated with the synergistic combination of ampicillin and cefotaxime even in preterm neonates.

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.

Assessment of clinical characteristics and treatment outcomes of pediatric patients with intracardiac thrombosis: a single-center experience

The prevalence of intracardiac thrombus (ICT) is gradually increasing, though it is rare among children. Data related to the occurrence of ICT among children are limited, and treatment recommendations have been made utilizing adult guidelines. The primary objective of this study is to determine associated factors, management, and outcomes of intracardiac thrombosis in children. Between January 2013 and January 2020, patients diagnosed with ICT at the Pediatric Hematology-Oncology and Pediatric Cardiology departments in our hospital were included in the study. Demographic characteristics, clinical and laboratory findings, treatment protocols, and outcomes were analyzed retrospectively. The median age at diagnosis was 10.5 months (2 days to 14.5 years), and the median follow-up period was 6.5 months (1 month to 3.1 years). The most common primary diagnoses of the patients, in order of frequency, were heart disease (n: 8), metabolic disease (n: 3), prematurity and RDS (n: 3), burns (n: 2), pneumonia (n: 2), and asphyxia (n: 2). CVC was present in 19/23 of the patients. The reasons for CVC insertion were the need for plasmapheresis in one patient with a diagnosis of HUS and the need for well tolerated vascular access because of long-term hospitalization in others. LMWH was administered to all patients as first-line therapy. Complete response was achieved in 19 (79%) of 24 patients and 4 patients (16.6%) were unresponsive to medical treatment. It was found out that the thrombus location, type, sepsis, and hemoculture positivity, as well as the presence of CVC, had no impact on treatment response (chi-square P = 0.16, 0.12, 0.3, 0.49, 0.56). Moreover, no correlation was determined between thrombus size and treatment response (Mann Whitney U test P = 0.47). The mortality rate was determined to be 12.5% (3/24). Spontaneous occurrence of ICT is rare in childhood, without any underlying primary disease or associated factor. The presence of CVC, sepsis, and heart disease are factors associated with ICT. The success rate is increased with medical treatment. There was no significant difference in treatment response between the newborn and 1 month to 18-year-old patient group. It has been demonstrated that thrombus size, type, localization; sepsis, and hemoculture positivity had no impact on the treatment response.

Occlusive Pulmonary Artery Thrombosis in a Healthy Neonate With No Identifiable Risk Factors

Pulmonary artery thrombosis is reported in neonates with risk factors for hypercoagulability. No consensus exists regarding standard therapy for this condition. We present a neonate, with no risk factors for thrombosis, who was admitted after birth to the Pediatric Cardiac Intensive Care Unit with an occlusive left pulmonary artery thrombus. (Level of Difficulty: Intermediate.).

Methicillin-Resistant Staphylococcus aureus Endovascular Infection in a Neonate: Prolonged, Safe, and Effective Use of Daptomycin and Enoxaparin

We report on a former 28-week gestation neonate with persistent methicillin-resistant Staphylococcus aureus (MRSA) endocarditis, with a heterozygous Factor V Leiden mutation. The neonate became clinically ill after 1 week of life, with positive blood cultures for MRSA. Echocardiography revealed large thrombi in the inferior vena cava and right atrium. Bacteremia persisted despite removal of umbilical arterial and venous catheters and empiric administration of therapeutic doses of vancomycin (minimum inhibitory concentration [MIC] 2 mg/L) and ceftazidime. To narrow therapy, ceftazidime was discontinued, while gentamicin and rifampin were added. Cultures remained positive and, therefore, linezolid was added, and subsequent blood cultures became negative. Since prolonged linezolid use of 2 weeks or longer carries potential adverse effects, antibiotics were changed to daptomycin, which is bactericidal and recommended for treatment of invasive MRSA infections when vancomycin MICs are ≥2 mg/L to minimize vancomycin treatment failure.

Enoxaparin was initiated, with anti-Xa assay monitoring. A workup for thrombophilia revealed heterozygous Factor V Leiden mutation. Serial echocardiograms demonstrated decreasing size of the thrombi, which were no longer visualized at 2 months of age. Creatinine kinase remained normal. The infant had no seizures on daptomycin. The management of persistent MRSA bacteremia in neonates associated with a large thrombus poses a unique challenge due to the long duration of treatment.

To our knowledge, this is the first case of prolonged and safe daptomycin and enoxaparin use in a preterm neonate. Daptomycin may be considered in cases of clinical failure with vancomycin when a lengthy treatment course is contemplated.

Clinical features and treatment results in preterm infants with intracardiac thrombus

INTRODUCTION

Thrombus incidence is higher among neonates, especially in preterm infants, due to the associated additional risk factors.

MATERIALS AND METHODS

The medical recordings of premature infants who had been diagnosed as having intracardiac thrombus between January 2016 and January 2019 were evaluated retrospectively. We use recombinant tissue plasminogen activator when the thrombus is relatively large compared to left atrium, pedunculated, mobile, or snake shaped.

RESULTS

A total of 13 premature patients were diagnosed as having intracardiac thrombus during the 3-year period. All were diagnosed during echocardiographic studies. Low molecular weight heparin was administered in four patients. In three, recombinant tissue plasminogen activator was started with low dose (0.01 mg/kg/h) and increased gradually to 0.06 mg/kg/h. In three, recombinant tissue plasminogen activators were started with standard dose (0.5 mg/kg/h). In one recombinant tissue, plasminogen activator was started with low dose (0.01 mg/kg/h) and increased to standard dose. Two patients died before treatment, three patients died during treatment, follow-up was not available for two patients, and thrombus completely resolved in six patients.

DISCUSSION

In preterm babies with risk factors, intracardiac thrombus should be kept in mind during all echocardiographic studies. In our patients, low and standard dose regimens were used, and the treatment results were similar.

Risk Factors for Intracardiac Thrombosis in the Right Atrium and Superior Vena Cava in Critically Ill Neonates who Required the Installation of a Central Venous Catheter

BACKGROUND

Central venous catheter (CVC) installation is essential for the treatment of critically ill neonates; however, it is associated with the development of neonatal intracardiac thrombosis, which is a complication that is associated with a poor prognosis. We aimed to identify specific risk factors for the development of intracardiac thrombosis in the right atrium (RA) and superior vena cava (SVC) related to the use of CVC in critically ill neonates.

METHODS

A case-control study was conducted at the tertiary referral neonatal intensive care unit of the Pediatric Hospital Siglo XXI in Mexico City, Mexico from 2008 to 2013. The included cases (n = 43) were de novo patients with intracardiac thrombosis in the RA and SVC diagnosed by echocardiography. The controls (n = 43) were neonates without intracardiac thrombosis or thrombosis at other sites. A logistic regression analysis was conducted, and odds ratios (ORs) and 95% confidence intervals (95% CIs) were calculated.

RESULTS

The independent risk factors for intracardiac thrombosis in the RA and SVC were the surgical cut-down insertion technique (OR = 2.98; 95% CI: 1.18-9.10), a maternal history of gestational diabetes/diabetes mellitus (OR = 10.64; 95% CI: 1.13-121.41), Staphylococcus epidermidis infection (OR = 7.09; 95% CI: 1.09-45.92), and CVC placement in the SVC (OR = 5.77; 95% CI: 1.10-30.18).

CONCLUSION

This study allowed us to identify several contributing factors to the development of intracardiac thrombosis in the RA and SVC related to the installation of a CVC in a subgroup of critically ill neonates. Multicenter and well-designed studies with a larger number of patients could help validate our findings and/or identify other risk factors that were not identified in the present study.

Pediatric Cardiac Intensive Care Society 2014 Consensus Statement: Pharmacotherapies in Cardiac Critical Care Hormone Replacement Therapy

OBJECTIVE

To provide an overview of the current literature on the use of hormone replacement therapies in pediatric cardiac critical care.

DATA SOURCES

PubMed, EMBASE, and the Cochrane Library were searched using keywords relevant to the hormonal therapy, with no limits on language but restricting the search to children 0-18 years old.

STUDY SELECTION

All clinical studies believed to have relevance were considered. Where studies in children were sparse, additional evidence was sought from adult studies.

DATA EXTRACTION

All relevant studies were reviewed, and the most relevant data were incorporated in this review.

DATA SYNTHESIS

All authors of this review contributed to the appraisal of the data extracted. Challenges and revisions by the authors were conducted by group e-mail debate.

CONCLUSIONS

Glycemic control: although it is likely that some children could benefit, the routine use of tight glycemic control cannot be recommended in children after cardiac surgery. Thyroid hormone replacement: routine use of thyroid hormone replacement to normalize levels after cardiac surgery cannot be recommended on current evidence. Until further evidence from adequately powered studies is available, therapeutic decisions should be based on individual patient circumstances. Corticosteroids: 1) cardiopulmonary bypass: although studies seem to favor steroid administration during surgery with cardiopulmonary bypass, a large randomized controlled trial is required before strong recommendations can be made; 2) refractory hypotension: the evidence for the use of steroid replacement in refractory hypotension is poor, and no firm recommendations can be made; and 3) abnormal adrenal function after cardiac surgery: there is inadequate evidence on which to make recommendations on the use of corticosteroid replacement in children with critical illness-related corticosteroid insufficiency in children following cardiac surgery.

Pediatric Cardiac Intensive Care Society 2014 Consensus Statement: Pharmacotherapies in Cardiac Critical Care Anticoagulation and Thrombolysis

OBJECTIVE

Thrombotic complications are increasingly being recognized as a significant cause of morbidity and mortality in pediatric and congenital heart disease. The objective of this article is to review the medications currently available to prevent and treat such complications.

DATA SOURCES

Online searches were conducted using PubMed.

STUDY SELECTION

Studies were selected for inclusion based on their scientific merit and applicability to the pediatric cardiac population.

DATA EXTRACTION

Pertinent information from each selected study or scientific review was extracted for inclusion.

DATA SYNTHESIS

Four classes of medications were identified as potentially beneficial in this patient group: anticoagulants, antiplatelet agents, thrombolytic agents, and novel oral anticoagulants. Data on each class of medication were synthesized into the follow sections: mechanism of action, pharmacokinetics, dosing, monitoring, reversal, considerations for use, and evidence to support.

CONCLUSIONS

Anticoagulants, antiplatelet agents, and thrombolytic agents are routinely used successfully in the pediatric patient with heart disease for the prevention and treatment of a wide range of thrombotic complications. Although the novel oral anticoagulants have been approved for a limited number of indications in adults, studies on the safety and efficacy of these agents in children are pending.

Recombinant tissue plasminogen activator as a novel treatment option for infective endocarditis: a retrospective clinical study in 32 children

Infective endocarditis is a life-threatening infectious syndrome, with high morbidity and mortality. Current treatments for infective endocarditis include intravenous antibiotics, surgery, and involve a lengthy hospital stay. We hypothesised that adjunctive recombinant tissue plasminogen activator treatment for infective endocarditis may facilitate faster resolution of vegetations and clearance of positive blood cultures, and therefore decrease morbidity and mortality. This retrospective study included follow-up of patients, from 1997 through 2014, including clinical presentation, causative organism, length of treatment, morbidity, and mortality. We identified 32 patients, all of whom were diagnosed with endocarditis and were treated by recombinant tissue plasminogen activator. Among all, 27 patients (93%) had positive blood cultures, with the most frequent organisms being Staphylococcus epidermis (nine patients), Staphylococcus aureus (six patients), and Candida (nine patients). Upon treatment, in 31 patients (97%), resolution of vegetations and clearance of blood cultures occurred within hours to few days. Out of 32 patients, one patient (3%) died and three patients (9%) suffered embolic or haemorrhagic events, possibly related to the recombinant tissue plasminogen activator. None of the patients required surgical intervention to assist vegetation resolution. In conclusion, it appears that recombinant tissue plasminogen activator may become an adjunctive treatment for infective endocarditis and may decrease morbidity as compared with current guidelines. Prospective multi-centre studies are required to validate our findings.

Thrombolysis for Severe Intestinal Ischemia due to Midgut Volvulus in a Neonate

Intestinal malrotation complicated by the development of midgut volvulus presents a difficult management dilemma because of the risk of short bowel syndrome. Here, we present our experience with a case of severe intestinal ischemia after derotation in a newborn successfully managed using systemic tissue plasminogen activator. The present report supports the usefulness of thrombolysis as a therapeutic option for reperfusion of ischemic small bowel due to midgut volvulus in neonates.

Treatment of neonatal fungal infective endocarditis with recombinant tissue plasminogen: activator in a low birth weight infant case report and review of the literature

With advances in medical sciences, an increase in survival rates of low birth weight; increased incidence in use of catheter and antibiotics, and total parenteral nutrition are reported, therefore, the rate of fungal infections in late and very late onset neonatal sepsis have increased. Although fungal endocarditis rarely occur in newborns, it has a high morbidity and mortality. Antifungal therapy is often insufficient in cases who develop fungal endocarditis and surgical treatment is not preferred due to its difficulty and high mortality. Herein, fungal endocarditis in a preterm newborn treated with single-dose recombinant tissue plasminogen activator in addition to antifungal therapy is presented and relevant literature has been reviewed. The vegetation completely disappeared following treatment and no complication was observed.

Intracardiac thrombus in children: the fine equilibrium between the risk and the benefit

The medical records of 16 patients diagnosed as intracardiac thrombus were searched. The size, location and outcome of thrombus together with demographic data of patients were assessed. The median age of the patients was 2.2 years. Six patients were newborn and two patients were infant. The median size of thrombus was 9 mm. The localization was right atrium in seven, right ventricle in five, left ventricle in one, pulmonary artery in one, and superior vena cava in two patients. There was prematurity in five, ciyanotic congenital heart disease in one, blood culture positivity in three, malignancy in four, nephrotic syndrome in one, indwelling catheters in 10, and acquired or genetic thrombophilia in six patients as risk factors. In the treatment, the first choice was tissue plasminogen activator in two patients, heparin infusion in one patient and low molecular weight heparin in remaining 12 patients. In nine patients, therapy included parenteral antimicrobials together with anticoagulants. The result was complete resolution in 15 patients and in one patient thrombus was surgically removed. The median time was 16 (2-70) days for 50% resolution and 26 (3-93) days for complete resolution. There was a statistically significant (P = .027 and r = 0.5) correlation between the size and the complete resolution time. There was no anticoagulant therapy related major complication. In patients with intracardiac thrombus, selection of anticoagulant therapy may decrease the risk of complications. Surgery is rarely required and thrombolytics are not usually necessary for resolution of thrombus.

Successful treatment of arterial thrombus in an extremely low-birth-weight preterm neonate

Arterial thromboembolism in the pediatric population frequently occurs secondary to arterial catheterization. Catheterization-related complications are more common in smaller and sicker infants, due to high prothrombotic activity, low levels of natural anticoagulants, and various fibrinolytic imbalances. Arterial thrombus management in neonates remains controversial. Recombinant tissue plasminogen activator is the most commonly used thrombolytic agent in children, however there is very little experience with recombinant tissue plasminogen activator therapy in small prematures, especially in the first week of life. This case study reports catheter-related femoral artery occlusion in an extremely low-birth-weight preterm infant. Despite continuous heparin infusion for 6 hours, no resolution of the thrombus was seen by clinicians. Heparin was stopped, and recombinant tissue plasminogen activator therapy enabled complete recovery from the thrombus. The risk of bleeding (including intracranial hemorrhage) with recombinant tissue plasminogen activator treatment, especially in small preterm neonates is unknown. However, in this extremely low-birth-weight preterm infant, recombinant tissue plasminogen activator therapy was effective, and limiting the infusion rate to ≤0.4 mg/kg/hour was safe.

Left atrium thrombus in an extremely low-birthweight infant with late-onset circulatory dysfunction

A left atrium thrombus, potentially a life-threatening complication, is an extremely rare in early infancy. Most cases are caused by mal-placement of central venous catheters or related to congenital heart diseases with left atrial blood congestion. Here we present an extremely low birth weight infant who developed a left atrial thrombus during the course of late onset circulatory dysfunction. The thrombus was successfully treated by recombinant tissue plasminogen activator. A hemodynamically unstable condition like late onset circulatory dysfunction should be taken into consideration as a potential risk condition of this rare disease.

Use of tissue plasminogen activator to treat intracardiac thrombosis in extremely low-birth-weight infants

OBJECTIVE

Intracardiac thrombosis is a life-threatening complication of extreme prematurity. We describe the use of tissue plasminogen activator to treat intracardiac thrombosis in extremely low-birth-weight preterm infants.

DESIGN

Case series, literature review, and practice guideline for recombinant tissue plasminogen activator treatment of intracardiac thrombosis in extremely low-birth-weight preterm infants.

SETTING

Neonatal intensive care.

PATIENTS

Four extremely low-birth-weight preterm infants coincidentally diagnosed with intracardiac thrombosis during neonatal intensive care.

INTERVENTIONS

Recombinant tissue plasminogen activator in a starting dose of 20 μg/kg/hr, increasing to 200-400 μg/kg/hr, infused for 2-6 days.

MEASUREMENTS AND MAIN RESULTS

Thrombolytic therapy with recombinant tissue plasminogen activator helped achieve rapid clot resolution in all infants and none had any major hemorrhagic complication associated with treatment.

CONCLUSIONS

Tissue plasminogen activator may safely be used to treat intracardiac thrombosis in extremely low-birth-weight preterm infants. Close monitoring of therapy is imperative. Further data are required to confirm the safety of tissue plasminogen activator in preterm infants.

A single-center experience with intracardiac thrombosis in children with dilated cardiomyopathy

Intracardiac thrombosis in patients with a dilated cardiomyopathy can be life threatening. This study investigated the incidence, risk factors, and outcome of intracardiac thrombosis in children with dilated cardiomyopathy. A retrospective review of the clinical records was performed in 83 children with dilated cardiomyopathy diagnosed from January 1995 to December 2008. Intracardiac thrombi were detected in 5 patients (6.0%). The intracardiac thrombi were found mainly in the left ventricle (n = 3). One patient had a thrombus in the left atrium at the time of diagnosis, and a right ventricular thrombus was found in 1 patient with unrepaired ventricular septal defect complicated by pulmonary hypertension. Intracardiac thrombosis developed during rapid deterioration of ventricular function, and all patients had a poor ejection fraction of the left ventricle. All patients were treated with heparinization, and thrombectomy was performed in 1 patient. Three patients achieved complete resolution of the thrombus without further embolic complications. Careful evaluation and aggressive anticoagulation are necessary for the prevention of intracardiac thrombosis in children with poor ventricular function, especially during rapid deterioration of ventricular function.

The use of recombinant tissue plasminogen activator in the management of infective intracardiac thrombi in pre-term infants with thrombocytopaenia

Bacterial endocarditis complicated by the development of intra-cardiac thrombus presents a difficult management dilemma in the pre-term infant. Here we present our experience with three infants who had this condition, all of whom were successfully managed using therapy with recombinant tissue plasminogen activator (r-TPA). Therapy in one of the infants was particularly instructive, as the condition was further complicated by severe thrombocytopaenia, making the decision to treat using r-TPA difficult.

The evaluation and management of postnatal thromboses

In the pediatric population, neonates have the highest risk for thromboembolism (TE), most likely due to the frequent use of intravascular catheters. This increased risk is attributed to multiple risk factors. Randomized clinical trials dealing with management of postnatal thromboses do not exist, thus, opinions differ regarding optimal diagnostic and therapeutic interventions. This review begins with an actual case study illustrating the complexity and severity of these types of cases, and then evaluates the neonatal hemostatic system with discussion of the common sites of postnatal thrombosis, perinatal and prothrombotic risk factors, and potential treatment options. A proposed step-wise evaluation of neonates with symptomatic postnatal thromboses will be suggested, as well as future research and registry directions. Owing to the complexity of ischemic perinatal stroke, this topic will not be reviewed.

The evaluation and management of neonatal coagulation disorders

Neonatal hemostatic abnormalities can present diagnostic and therapeutic challenges to the physician. Developmental deficiencies and/or increases of certain coagulation proteins, coupled with acquired or genetic risk factors, can result in a hemorrhagic or thromboembolic emergency. The timely diagnosis of a congenital hemorrhagic or thrombotic disorder can avoid significant long-term sequelae. However, due to the lack of randomized clinical trials addressing the management of neonatal coagulation disorders, treatment strategies are usually empiric and not evidence-based. In this chapter, we will review the neonatal hemostatic system and will discuss the most common types of hemorrhagic and thrombotic disorders. Congenital and acquired risk factors for hemorrhagic and thromboembolic disorders will be presented, as well as current treatment options. Finally, suggested evaluations for neonates with either hemorrhagic or thromboembolic problems will be reviewed.

Catheter-directed thrombolysis of inferior vena cava thrombosis in a 13-day-old neonate and review of literature

Complete inferior vena cava thrombosis (IVC) in neonates is uncommon, but may cause significant morbidity. A 13-day-old neonate suffered IVC thrombosis secondary to antithrombin III deficiency, possibly contributed to by a mutation in the methyl tetrahydrofolate reductase gene. Catheter-directed thrombolysis (CDT) with recombinant tissue plasminogen activator (rt-PA, Alteplase) was used successfully to treat extensive venous thrombosis in this neonate without complications. We also review the literature on CDT for treatment of IVC thrombosis in critically ill neonates and infants.

Tissue plasminogen activator for a left atrial thrombus after Senning repair

OBJECTIVE

To avoid the surgical removal of an obstructive thrombus in a Senning baffle by the administration of recombinant tissue-type plasminogen activator.

SETTING

A pediatric intensive care unit in a children's university hospital.

PATIENTS

A 3-yr-old male was diagnosed with a large left atrial thrombus 2 wks after Senning repair for D-transposition of the great arteries. The child presented with massive chylous pleural, pericardial effusions, and cardiac tamponade, secondary to partial obstruction of the pulmonary venous channel.

INTERVENTION

Thrombolysis with recombinant tissue-type plasminogen activator was instituted.

RESULTS

We observed a resolution of the thrombus in <48 hrs. Minor local bleeding was the only noted side effect. No signs of systemic thromboembolization were detected.

CONCLUSION

Early thrombolysis with recombinant tissue-type plasminogen activator could be considered a possible alternative to surgical thrombectomy in selected postoperative pediatric cases, although there may be a potential risk of serious bleeding.

A giant thrombus in the right ventricle of a newborn with Down syndrome: successful treatment with rt-PA

An association between thromboembolic events and Down syndrome (DS) has been increasingly reported in the literature. It is not clear whether patients with DS have increased risk for thrombotic disorders or there is a coincidence. We present a case of giant right ventricular thrombus in a neonate with DS. Risk factors for thrombosis in the present case were neonatal sepsis and dehydration. There was no congenital heart anomaly. The patient was treated successfully using recombinant tissue plasminogen activator. Recombinant tissue plasminogen activator seems to be a safe and effective thrombolytic therapy in neonates.

Cardiac thrombus in Omenn syndrome

Omenn syndrome is characterized by a generalized erythematous skin rash, lymph node enlargement, hepatosplenomegaly, Increased serum IgE levels, eosinophilia, and evidence of severe combined immune deficiency. Patients develop fungal, bacterial, and viral infections. We present the case of a 3-month-old girl with Omenn syndrome who developed right ventricular thrombosis. Echocardiographic study revealed a round structure that filled the apex and corpus of the the right ventricle. We investigated this patient for hypercoagulation and made a diagnosis of ventricular thrombosis, which is an uncommon finding in Omenn syndrome.

Central venous catheter techniques in infants and children

PURPOSE OF REVIEW

The placement of central venous catheters is often necessary to facilitate optimal anaesthetic and perioperative management or for the long-term management of chronic underlying diseases. Insertion may be a challenge in selected patients, and the risk of infection, thrombosis, and other complications may result in significant risk factors.

RECENT FINDINGS

Ultrasound visualization of the cervical veins with Valsalva manoeuvres significantly increases the rate and safety of central venous cannulation, and decreases needle passes in paediatric patients even with experienced operators. Pericardial effusion with tamponade is a more frequent phenomenon than generally realized, and accurate location of the catheter-tip position is essential. The femoral venous approach has proved to be safe even in premature babies. Clear guidelines for infection control and the prevention of intravascular catheter-related infections in children have been established; however, the high incidence of nosocomial catheter-related infections requires effective prevention strategies. The impact of antimicrobial-impregnated central venous catheters on the prevention of bloodstream infections in children is not yet clear. Routine use of prophylactic antibiosis (i.e. vancomycin) to prevent catheter-related infection cannot be recommended. Thrombolytic therapy with recombinant tissue plasminogen activator is safe, efficient, well tolerated and effective for lysis of catheter-induced intravascular and intracardiac thrombi even in neonates. Embolized catheter fragments can be retrieved in neonates and children by non-surgical interventions using standard procedures applied by paediatric cardiologists.

SUMMARY

Despite a variety of new techniques, the major problem of central venous catheterization in neonates and children remains the prevention of catheter-related infection and infection control.

Successful local low-dose urokinase treatment of acquired thrombosis early after cardiothoracic surgery

BACKGROUND AND OBJECTIVE

Recent surgery (<or=10 days) is considered an absolute contraindication for thrombolytic therapy. We report the successful use of low doses of urokinase locally infused to dissolve an intravascular thrombosis in the early postoperative period after congenital heart surgery.

PATIENTS

Two children, with catheter-related intravascular thrombosis after cardiac surgery, received urokinase treatment within 24 hrs and 6 days of surgery, respectively.

SETTING

Tertiary, 11-bed, pediatric intensive care unit.

INTERVENTIONS

Urokinase was administered through the catheter close to the site of thrombosis with a bolus of 4400 units/kg followed by a continuous infusion of 1300 units x kg(-1) x hr(-1).

MAIN RESULTS

Thrombosis resolved completely in both patients after 3 days of therapy. Signs of systemic thrombolysis were not observed.

CONCLUSIONS

A short course of local low-dose urokinase is feasible and seems to be effective for thrombolysis of catheter-related thrombosis early after cardiothoracic surgery. It was not associated with bleeding in the two cases presented. Further studies are required to confirm the safety of this approach and to define optimal dosing.