Tissue Plasminogen Activator Use in Children: Bleeding Complications and Thrombus Resolution

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.

Clinical characteristics and outcomes of combined thrombolysis and anticoagulation for pediatric and young adult lower extremity and inferior vena cava thrombosis

Effective treatment for acute, extensive, symptomatic lower extremity (LE) thrombosis involves thrombolysis in addition to anticoagulation. There is limited available data on the outcomes and safety of thrombolysis to help guide its use in pediatrics and young adults. A retrospective study of children and young adults (<21 years of age) that received catheter directed thrombolysis (CDT) for LE and inferior vena cava (IVC) thrombosis was performed over a 5-year span at a pediatric tertiary care center. A total of 29 patients were identified for inclusion in the study, 76% (n = 22) received overnight CDT while 24% (n = 7) received tissue plasminogen activator as a bolus dose during a single interventional procedure. The median age of the cohort was 15.8 years (range 0-19.1). All patients were treated with a course of therapeutic anticoagulation. The thromboses represented were extensive, with 93% (n = 27) being occlusive and affecting multiple venous segments. Thrombus resolution occurred in 35% (n = 10) of patients. Rivaroxaban use (p < 0.01) during the course of anticoagulation and estrogen-containing hormonal therapy (p = 0.01) use prior to diagnosis were associated with thrombus resolution, while Hispanic ethnicity (p = 0.06) had a trend toward thrombus persistence. There were one major and 3 minor bleeding events that occurred as complications of thrombolysis and no treatment related deaths. This study provides baseline information that can be used to help guide clinicians treating similar patients and suggests the need to develop an improved, uniform treatment approach for superior resolution rates.

Catheter-directed thrombolysis for in situ pulmonary artery thrombosis in children

In situ pulmonary artery thrombosis (ISPAT) is a unique form of pulmonary embolism characterized by local formation of thrombus in the pulmonary arteries. We present here a baby with hypoplastic left heart syndrome who developed ISPAT after Glenn surgery. The patient underwent catheter-directed thrombolysis, followed by systemic anticoagulation with excellent results.

Patient Characteristics and Treatment Outcomes of Symptomatic Catheter-Related Arterial Thrombosis in Infants: A Retrospective Cohort Study

OBJECTIVE

To describe the clinical characteristics, outcomes, and adverse events of treatment for symptomatic infant catheter-related arterial thrombosis.

STUDY DESIGN

Single-center retrospective medical record review of 99 infants (age <365 days) with catheter-related arterial thrombosis, either following indwelling arterial catheter placement or cardiac catheterization, who were treated with anticoagulation over an 8-year span at a pediatric tertiary care center. Outcomes measured include thrombosis progression, bleeding events, and thrombus resolution following the treatment period.

RESULTS

Thromboses were secondary to indwelling arterial catheter placement in 51 (51.5%) and cardiac catheterization in 48 (48.5%). The median age at diagnosis of catheter-related arterial thrombosis was 52 days. All patients received therapeutic anticoagulation with either unfractionated heparin or low molecular weight heparin for a maximum of 28 days. Progression of catheter-related arterial thrombosis occurred in 8 (8.1%) patients. One (1%) major and 3 (3%) minor bleeding events occurred within the cohort. Complete thrombus resolution was observed in 60 (60.6%), partial resolution in 33 (33.3%), and no resolution in 6 (6.1%) following the treatment period. Factors associated with complete thrombus resolution included time from intervention to catheter-related arterial thrombosis diagnosis (median of 1 day vs 5 days in those who experienced thrombus resolution vs those who did not, P = .035), and iliac and/or femoral artery involvement (P = .015).

CONCLUSIONS

Our treatment approach to infant catheter-related arterial thrombosis is safe and effective. Limitations of the study are its retrospective nature with a limited number of patients from a single institution. Additional prospective studies are needed to determine the optimal treatment approach to catheter-related arterial thrombosis in infants.

Thrombolytic therapy in preterm infants: Fifteen-year experience

OBJECTIVE

To report a single-center experience with thrombolytic therapy using recombinant tissue plasminogen activator (rt-PA) in preterm neonates with severe thrombotic events, in terms of thrombus resolution and bleeding complications.

STUDY DESIGN

This retrospective study included 21 preterm neonates with severe venous thrombotic events admitted to the neonatal intensive care unit, identified in our pharmacy database from January 2001 to December 2016, and treated with rt-PA until complete or partial clot lysis, no-response or bleeding complications. Our primary outcome was thrombus resolution.

RESULTS

Twenty-one preterm neonates were treated with rt-PA for an average of 2.9 cycles. Seventeen patients (80.9%) had superior vena cava thrombosis and superior vena cava syndrome. All patients had a central venous catheter, parenteral nutrition, mechanical ventilation, and sepsis. Fifteen patients (71.4%) were extremely preterm, 11 (52.4%) were extremely low birth weight, and seven (33.3%) were very low birth weight. The patency rate was 85.7%, complete lysis occurred in 11 (52.4%) patients, and partial lysis in seven (33.3%). Minor bleeding occurred in five (23.8%) patients, three patients (14.2%) had clinically relevant nonmajor bleeding events, and major bleeding occurred in six (28%) patients.

CONCLUSION

In this study, the rate of thrombus resolution in preterm neonates treated with rt-PA were similar to the percentages reported in children and adolescents, with a high rate of bleeding. Therefore, rt-PA thrombolytic therapy should only be considered as a treatment option for severe life-threatening thrombosis in premature neonates for whom the benefits of the thrombolytic treatment outweigh the risks of bleeding.

Reperfusion Injury with Compartment Syndrome Following Systemic Thrombolysis for Cardiac Catheterization-Related Arterial Thrombosis in an Infant

Systemic thrombolysis is increasingly used for management of arterial thrombosis following cardiac catheterization, and complications apart from bleeding manifestations are not well reported. We report the case of an infant with lower limb ischemia secondary to femoral arterial thrombosis, which developed after cardiac catheterization. Systemic thrombolysis resulted in successful reperfusion of the lower limb. However, the infant subsequently developed compartment syndrome, requiring an emergent fasciotomy. This case highlights the importance of surveillance for the development of reperfusion injury-related compartment syndrome postsystemic thrombolysis for arterial thrombosis.

Thrombolysis Using Tissue Plasminogen Activator: Experience from a Critical Care Setting

To describe the experience of thrombolysis using tissue plasminogen activator (tPA) in critically ill children admitted to the pediatric intensive care unit (PICU), retrospective review of medical records of all children (1 month-16 years), who were admitted in PICU since January 2014 to December 2017 and received systemic tPA for thrombolysis was done. Data was collected on a structured proforma and included thrombus location, tPA dose and duration, outcome (resolution, survival) and complications (bleeding). Total 9 patients (7 males, 2 females) received systemic tPA therapy for thrombolysis with mean age of 74.64 ± 69.58 months. Two patients had thrombus in femoral artery, 3 in IVC and 4 had intra-cardiac thrombosis. Median number of doses was 2 with a range of 1-5 doses. Complete resolution of the clot was noted in all except one patient. A standard starting dose of 0.01 mg/kg/h was used in all patients. Only one patient developed melena after TPA therapy which self-resolved. Systemic tPA therapy was very safe in pediatric critically ill patients and was effective for thrombolysis and did not show any adverse effects in children with varying underlying diagnosis.

Efficacy and safety of recombinant tissue plasminogen activator for venous thrombosis after paediatric heart surgery

OBJECTIVE

Reports in the literature of treatment with recombinant tissue plasminogen activator following cardiac surgery are limited. We reviewed our experience to provide a case series of the therapeutic use of tissue plasminogen activator for the treatment of venous thrombosis in children after cardiac surgery. The data describe the morbidity, mortality, and clinical outcomes of tissue plasminogen activator administration for treatment of venous thrombosis in children following cardiac surgery.

DESIGN

The study was designed as a retrospective case series.

SETTING

The study was carried out in a 25-bed cardiac intensive care unit in an academic, free-standing paediatric hospital. Patients All children who received tissue plasminogen activator for venous thrombosis within 60 days of cardiac surgery, a total of 13 patients, were included. Interventions Data was collected, collated, and analysed as a part of the interventions of this study. Measurements and main results Patients treated with tissue plasminogen activator were principally young infants (median 0.2, IQR 0.07-0.58 years) who had recently (22, IQR 12.5-27.3 days) undergone cardiac surgery. Hospital mortality was high in this patient group (38%), but there was no mortality attributable to tissue plasminogen activator administration, occurring within <72 hours. There was one major haemorrhagic complication that may be attributable to tissue plasminogen activator. Complete or partial resolution of venous thrombosis was confirmed using imaging in 10 of 13 patients (77%), and tissue plasminogen activator administration was associated with resolution of chylous drainage, with no drainage through chest tubes, at 10 days after tissue plasminogen activator treatment in seven of nine patients who had upper-compartment venous thrombosis-associated chylothorax.

CONCLUSIONS

On the basis of our experience with administration of tissue plasminogen activator in children after cardiac surgery, tissue plasminogen activator is both safe and effective for resolution of venous thrombosis in this high-risk population.

Recombinant tissue plasminogen activator to restore catheter patency: efficacy and safety analysis from a multihospital NICU system

OBJECTIVE

In 2001, the US Food and Drug Administration approved recombinant tissue plasminogen activator (alteplase, Cathflo Activase) to reestablish patency of central catheters occluded, presumably, by a fibrin clot. We conducted a multicenter quality improvement study to determine the value of this procedure in our Neonatal Intensive Care Unit (NICUs), including analyses of efficacy, safety and costs.

STUDY DESIGN

We conducted a retrospective quality analysis of neonates in level III NICUs, who received alteplase for the purpose of reestablishing patency of occluded central catheters.

RESULTS

Alteplase was administered to 169 neonates, each given one to four doses, totaling 205 episodes of administration. The most common type of catheter where alteplase was used was percutaneously inserted central catheter (PICC) lines (78% of uses), 8% were umbilical venous catheters (UVCs), 6% arterial lines, 5% chest tubes and 3% other catheters. Postnatal age at first dose ranged from 0 to 132 days (median, 12); dosed patients were 22 to 41 weeks gestation at birth (median, 31). Fifty-eight percentage of administrations restored catheter function. Success was more likely at younger postnatal age (10±2 days old in successful vs 14±1 days in unsuccessful treatments; P=0.023). Seventy-two percentage of the re-canalized catheters remained functional until they were no longer needed (2 to 30 days later). Nine percentage of episodes were treated with a second dose 1 to 17 days later for re-occlusion and 50% of those were successful. Bleeding consequences were identified in only one case, where three separate lines were treated (chest tube, PICC and UVC) within a 6-h period. Costs to the health system of doses, minus savings to the system by not needing to replace lines, averaged a net of $34 per dose.

CONCLUSIONS

The apparent safety and favorable value analysis prompted us to develop a consistent approach to alteplase usage in the Intermountain Healthcare NICUs, using the data in this report to standardize the guidelines across our health system.