Platelet Inhibition in Shunted Infants on Aspirin at Short and Midterm Follow-Up

Adverse Drug Reactions in Children with Congenital Heart Disease: A Scoping Review

BACKGROUND

Congenital heart disease (CHD) is one of the leading causes of death. Safe and timely medical interventions, especially in children, can prolong their survival. The drugs prescribed for children with CHD are mainly based on the outcomes of drug therapy in adults with cardiovascular diseases, and their adverse drug reactions (ADRs) might be different. Therefore, the aim of this study was to investigate ADRs in children with CHD.

METHODS

This was a scoping review conducted in 2023. PubMed, Web of Science, Scopus, the Cochrane Library, Ovid, ProQuest, and Google Scholar databases were searched. All studies that reported ADRs for children with CHD and were published in English by 1 November 2023 were included in this study. Finally, the results were reported using a content analysis method.

RESULTS

A total of 87 articles were included in the study. The results showed that symptoms/signs/clinical findings, and cardiovascular disorders were the most common ADRs reported in children with CHD. The results also showed that most of the ADRs were reported for prostaglandin E1, amiodarone, prostaglandin E2, dexmedetomidine, and captopril, respectively.

CONCLUSION

The review underscores the wide array of ADRs in children with CHD, particularly in antiarrhythmics, diuretics, beta-blockers, anticoagulants, and vasodilators, which affected cardiovascular, respiratory, endocrine, metabolic, genitourinary, gastrointestinal, and musculoskeletal systems. Tailored treatment is imperative, considering individual patient characteristics, especially in the vulnerable groups. Further research is essential for optimizing dosing, pharmacogenetics, and alternative therapies to enhance patient outcomes in CHD management.

The Effects of Aspirin dose in Children with Congenital and Acquired Heart Disease. Results from the Paediatric Study of Aspirin Efficacy using Diagnostic and Monitoring Tools (PAED-M)

The optimal dose of aspirin required in children with congenital and acquired heart disease is not known. The primary aim of this prospective observational study was to evaluate the effects of aspirin dose on platelet inhibition. The secondary aim was to determine the prevalence and clinical predictors of aspirin non-responsiveness. Measurements were by Thromboelastography with Platelet Mapping (TEGPM) only in children less than 2 years (y) of age with particular emphasis on the parameter known as maximum amplitude with arachidonic acid (MAAA) and using both TEGPM, and light transmission aggregometry (LTA) in children greater than 2 y. We prospectively studied 101 patients with congenital and acquired cardiac disease who were receiving empirical doses of aspirin for a minimum of 4 weeks but no other antiplatelet agents. Patients were stratified according to dose concentration and age. There was a trend toward lower age in patients with no response or semi-response to aspirin. All patients were considered responsive to aspirin in the higher-dose quartile (Q4) with a median dose of 4.72 (4.18-6.05) mg/kg/day suggesting that patients in this age group may require 5 mg/kg/day as an empirical dose. In children > 2 y, there was no significant difference in inhibition found in patients dosed at higher doses in Q3 versus Q4 suggesting that patients in this cohort are responsive with 3 mg/kg/day dose. The current practices may lead to reduced platelet inhibition in some children due to under-dosing or overdosing in others. In conclusion, younger children require higher doses of aspirin. Laboratory assessment is warranted in this population to mitigate against under and overdosing.

Current evidence for pharmacologic therapy following stage 1 palliation for single ventricle congenital heart disease

INTRODUCTION

Infants with single ventricle congenital heart disease are vulnerable to complications between stage 1 and stage 2 of palliation. Pharmaceutical treatment during this period is varied and often dependent on institutional practices as there is little evidence supporting a particular treatment path.

AREAS COVERED

This review focuses on medical management of patients following stage I palliation. We performed a scoping review of the current literature regarding angiotensin converting enzyme inhibitors and digoxin treatment in the interstage period. In addition, we discuss other medication classes frequently used in these patients.

EXPERT OPINION

Due to significant heterogeneity of anatomy, rarity of disease, and other confounding factors, there is limited evidence to support most commonly used medications within the interstage period. Digoxin is associated with improved mortality within the interstage period and should be considered; however, no large randomized controlled trial exists supporting its use. Prevention of thrombotic complication with aspirin is also associated with improved outcomes and should be considered unless a contraindication exists. The addition of other prescriptions in this patient population should be considered only after an evaluation of the risks and benefits of each medication, recognizing the burden and risk of polypharmacy in this fragile patient population.

Platelet Aggregation Before Aspirin Initiation in Pediatric Patients With Congenital Heart Disease at High Risk of Thrombosis

Background

Aspirin following unfractionated heparin is the most common anticoagulation strategy for pediatric patients who experienced cardiac surgery at high risk of thrombosis. The platelet aggregation test is the golden method to evaluate the aspirin effect on platelet function. However, the platelet aggregation basal status before postoperative aspirin initiation and the related clinical influencing factors hasn't been investigated systemically in this population.

Methods

In a prospective cohort of 247 children, arachidonic acid-induced platelet aggregation (PAG-AA) was measured by means of light transmission aggregometry (LTA) before the first dose of aspirin after cardiac surgical procedure and the perioperative variables were also collected. Distribution of this population's PAG-AA basal status was described. Univariate and multivariate logistic regression analysis were performed to identify the main influencing factors of PAG-AA.

Results

The median time of aspirin administration was 2 (1–27) days after surgery and the corresponding median value of basal PAG-AA was 20.70% (1.28–86.49%), with 67.6% population under 55% and 47.8% population under 20%. Patients undergoing cardiopulmonary bypass (CPB) had a significantly lower basal PAG-AA than those without (30.63 ± 27.35 vs. 57.91 ± 27.58, p = 0.013). While patients whose test done within 3 days after CPB had a significantly lower PAG-AA than those out of 3 days (25.61 ± 25.59 vs. 48.59 ± 26.45, p = 0.001). Univariate analysis implied that the influencing factors of the basal PAG-AA including CPB use, test time point, cyanosis, and platelet count. Multivariate regression analysis indicated that only CPB use, test time point, and platelet count were the main independent influencing factors for the basal PAG-AA.

Conclusion

The majority of children have impaired basal platelet aggregometry responses before postoperative aspirin initiation. The main influencing factors are CPB use, test time point, and platelet count. To establish the platelet aggregometry baseline prior to commencement of aspirin therapy, testing should be performed 3 days later following the procedure when effect of CPB is basically over.

Application of a TEG-Platelet Mapping Algorithm to Guide Reversal of Antiplatelet Agents in Adults with Mild-to-Moderate Traumatic Brain Injury: An Observational Pilot Study

BACKGROUND

Traumatic intracranial hemorrhages expand in one third of cases, and antiplatelet medications may exacerbate hematoma expansion. However, the reversal of an antiplatelet effect with platelet transfusion has been associated with harm. We sought to determine whether a thromboelastography platelet mapping (TEG-PM)-guided algorithm could limit platelet transfusion in patients with hemorrhagic traumatic brain injury (TBI) prescribed antiplatelet medications without a resultant clinically significant increase in hemorrhage volume, late hemostatic treatments, or delayed operative intervention.

METHODS

A total of 175 consecutive patients with TBI were admitted to our university-affiliated, level I trauma center between March 2016 and December 2019: 54 preintervention patients (control) and 121 patients with TEG-PM (study). After exclusion for anticoagulant administration, availability of neuroimaging and emergent neurosurgery, 62 study patients and 37 control patients remained. Intervention consisted of administration of desmopressin (DDAVP) for nonsurgical patients with significant inhibition at the arachidonic acid or adenosine diphosphate receptor sites. For surgical patients with significant inhibition, dual therapy with DDAVP and platelet transfusion was employed. Study patients were compared with a group of historical controls, which were identified from a prospectively maintained registry and typically treated with empiric platelet transfusion.

RESULTS

Median age was 75 years (interquartile range 85-67) and 77 years (interquartile range 81-65) in the TEG-PM and control patient groups, respectively. Admission hemorrhage volumes were similar (10.7 cm³ [20.1] in patients with TEG-PM vs. 14.1 cm³ [19.7] in controls; p = 0.41). There were no significant differences in admission Glasgow Coma Scale, mechanism of trauma, or baseline comorbidities. A total of 57% of controls versus 10% of patients with TEG-PM (p < 0.001) were transfused platelets; 52% of intervention patients and 0% controls were treated with DDAVP. Expansion hemorrhage volumes were not significantly different (14.0 cm³ [20.2] patients with TEG-PM versus 13.6 cm³ [23.7] controls; p = 0.93). There was no significant difference in rates of clinical deterioration, delayed neurosurgical intervention, or late platelet transfusion between groups.

CONCLUSIONS

Among patients with hemorrhagic TBI prescribed preinjury antiplatelet therapy, our study suggests that the use of a TEG-PM algorithm may reduce platelet transfusions without a concurrent increase in clinically significant hematoma expansion. Further study is required to prove a causative relationship.

A Narrative Review of Postoperative Anticoagulation Therapy for Congenital Cardiac Disease

Congenital heart disease encompasses a range of cardiac birth defects. Some defects require early and complex surgical intervention and post-operative thromboprophylaxis primarily for valve, conduit, and shunt patency. Antiplatelet and anticoagulant management strategies vary considerably and may or may not align with recognized consensus practice guidelines. In addition, newer anticoagulant agents are being increasingly used in children, but these medications are not addressed in most consensus statements.

This narrative review evaluated the literature from 2011 through 2021 on the topic of postoperative thromboprophylaxis after congenital heart disease operations. The search was focused on the descriptions and results of pediatric studies for replacement and/or repair of heart valves, shunts, conduits, and other congenital heart disease operations. Wide variability in practice exists and, as was true a decade ago, few randomized controlled trials have been conducted. Aspirin, warfarin, and perioperative heparin remain the most commonly used agents with varying dosing, duration, and monitoring strategies, making comparisons difficult. Only recently have data on direct oral anticoagulants been published in children, suggesting evolving paradigms of care. Our findings highlight the need for more research to strengthen the evidence for standardized thromboprophylaxis strategies.

Efficacy and Safety of NSAIDs in Infants: A Comprehensive Review of the Literature of the Past 20 Years

Non-steroidal anti-inflammatory drugs (NSAIDs) are commonly used in infants, children, and adolescents worldwide; however, despite sufficient evidence of the beneficial effects of NSAIDs in children and adolescents, there is a lack of comprehensive data in infants. The present review summarizes the current knowledge on the safety and efficacy of various NSAIDs used in infants for which data are available, and includes ibuprofen, dexibuprofen, ketoprofen, flurbiprofen, naproxen, diclofenac, ketorolac, indomethacin, niflumic acid, meloxicam, celecoxib, parecoxib, rofecoxib, acetylsalicylic acid, and nimesulide. The efficacy of NSAIDs has been documented for a variety of conditions, such as fever and pain. NSAIDs are also the main pillars of anti-inflammatory treatment, such as in pediatric inflammatory rheumatic diseases. Limited data are available on the safety of most NSAIDs in infants. Adverse drug reactions may be renal, gastrointestinal, hematological, or immunologic. Since NSAIDs are among the most frequently used drugs in the pediatric population, safety and efficacy studies can be performed as part of normal clinical routine, even in young infants. Available data sources, such as (electronic) medical records, should be used for safety and efficacy analyses. On a larger scale, existing data sources, e.g. adverse drug reaction programs/networks, spontaneous national reporting systems, and electronic medical records should be assessed with child-specific methods in order to detect safety signals pertinent to certain pediatric age groups or disease entities. To improve the safety of NSAIDs in infants, treatment needs to be initiated with the lowest age-appropriate or weight-based dose. Duration of treatment and amount of drug used should be regularly evaluated and maximum dose limits and other recommendations by the manufacturer or expert committees should be followed. Treatment for non-chronic conditions such as fever and acute (postoperative) pain should be kept as short as possible. Patients with chronic conditions should be regularly monitored for possible adverse effects of NSAIDs.

A systematic review of the evidence supporting post-operative antithrombotic use following cardiopulmonary bypass in children with CHD

OBJECTIVES

To determine the optimal antithrombotic agent choice, timing of initiation, dosing and duration of therapy for paediatric patients undergoing cardiac surgery with cardiopulmonary bypass.

METHODS

We used PubMed and EMBASE to systematically review the existing literature of clinical trials involving antithrombotics following cardiac surgery from 2000 to 2020 in children 0-18 years. Studies were assessed by two reviewers to ensure they met eligibility criteria.

RESULTS

We identified 10 studies in 1929 children across three medications classes: vitamin K antagonists, cyclooxygenase inhibitors and indirect thrombin inhibitors. Four studies were retrospective, five were prospective observational cohorts (one of which used historical controls) and one was a prospective, randomised, placebo-controlled, double-blind trial. All included were single-centre studies. Eight studies used surrogate biomarkers and two used clinical endpoints as the primary endpoint. There was substantive variability in response to antithrombotics in the immediate post-operative period. Studies of warfarin and aspirin showed that laboratory monitoring levels were frequently out of therapeutic range (variably defined), and findings were mixed on the association of these derangements with bleeding or thrombotic events. Heparin was found to be safe at low doses, but breakthrough thromboembolic events were common.

CONCLUSION

There are few paediatric prospective randomised clinical trials evaluating antithrombotic therapeutics post-cardiac surgery; most studies have been observational and seldom employed clinical endpoints. Standardised, validated endpoints and pragmatic trial designs may allow investigators to determine the optimal drug, timing of initiation, dosing and duration to improve outcomes by limiting post-operative morbidity and mortality related to bleeding or thrombotic events.

Preoperative Aspirin Management in Redo Tetralogy of Fallot Population: Single Centre Experience

Purpose: Redo operations and preoperative antiplatelet/anticoagulant therapy can significantly increase surgical risk in congenital heart surgery. This is a retrospective study on the impact of preoperative aspirin therapy on the outcome of Tetralogy of Redo Fallot patients undergoing right ventricle outflow tract (RVOT) conduit implantation. Methods: Ten-years retrospective analysis of medical records was carried out. A total of 72 patients were divided into two groups: “Daily-on-ASA” group on daily therapy with aspirin (ASA) until 5 days from surgery and “No-Home-ASA” without it. Propensity match analysis was done in order to standardize the populations. Intraoperative and postoperative lengths were compared as well as the need for inotropic support. In addition, differences in blood transfusions and need for Fresh frozen plasma (FFP)/platelets (PLT) were analysed. Findings: Intraoperative lengths were similar between the groups. Not statistically significative differences about postoperative time to extubation (p = 0.34), ICU Stay (p = 0.31) or in-hospital stay (p = 0.36) were found. Drain loss was higher in the “Daily-on-ASA” group (407.9 ± 96.7 mL vs. 349.5 ± 84.3 mL; p = 0.03) as well as blood transfusions (372.7 ± 255.1 mL vs. 220.1 ± 130.3 mL, p = 0.02) and PLT/FFP need (217.7 ± 132.1 mL vs. 118.7 ± 147.1 mL, p = 0.01). No differences were found in postoperative complications or re-explorations for bleeding. Implications: We found no advantages in surgical times and hospital stay comparing redo patients who stopped aspirin versus those that didn’t take it in the last 6 months. However, our results suggest that redo patients undergoing RVOT conduit implantation who take daily aspirin are at higher risk of bleeding even if it is stopped 5 days before surgery.

Platelet Inhibition With IV Glycoprotein IIb/IIIa Inhibitor to Prevent Thrombosis in Pediatric Patients Undergoing Aortopulmonary Shunting

OBJECTIVES

Shunt thrombosis, a potential complication of aortopulmonary shunting, is associated with high mortality. Commonly used oral antiplatelet drugs such as aspirin demonstrate variable absorption and inconsistent antiplatelet effect in critically ill patients early after surgery. IV glycoprotein IIb/IIIa inhibitors are antiplatelet agents with rapid and reproducible effect that may be beneficial as a bridge to oral therapy.

DESIGN

Retrospective review of pediatric patients undergoing treatment with IV tirofiban. Discarded blood samples were used to determine pharmacokinetic parameters.

SETTING

Pediatric cardiac ICU at a single institution.

PATIENTS

Fifty-two pediatric patients (< 18 yr) undergoing surgical aortopulmonary shunt procedure who received tirofiban infusion as a bridge to oral aspirin.

INTERVENTIONS

None.

MEASUREMENTS AND MAIN RESULTS

Primary outcome measures were shunt thrombosis and bleeding events, whereas secondary outcomes included measurement of platelet inhibition by thromboelastography with platelet mapping and pharmacokinetic analysis (performed in a subset of 15 patients). Shunt thrombosis occurred in two of 52 patients (3.9%) after prophylaxis treatment with tirofiban; both thrombosis events occurred after discontinuation of the drug. One patient (1.9%) experienced bleeding complication during the infusion. A tirofiban bolus of 10 µg/kg and infusion of 0.15 µg/kg/min resulted in significantly increased platelet inhibition via adenosine diphosphate pathway (median 66% [43-96] pre-tirofiban compared with 97% [92-99%] at 2 hr; p < 0.05). Half-life of tirofiban in plasma was 142 ± 1.5 minutes, and the average steady-state concentration was 112 ± 62 ng/mL. Age and serum creatinine were significant covariates associated with systemic clearance. Dosing simulations were generated based upon one compartment model.

CONCLUSIONS

IV glycoprotein IIb/IIIa inhibitor as a bridge to oral antiplatelet therapy is safe in pediatric patients after aortopulmonary shunting. Dosing considerations should include both age and renal function. Randomized trials are warranted to establish efficacy compared with current anticoagulation practices.

Aspirin in childhood acute ischemic stroke: The evidence for treatment and efficacy testing

Aspirin is the most commonly prescribed antiplatelet agent worldwide, but evidence supporting its use varies by age and disease process. Despite its frequent use in childhood acute ischemic stroke prevention and management, major knowledge gaps exist about optimal pediatric aspirin use, particularly in this setting, where high-quality clinical trials are urgently needed. This review focuses upon the evidence for aspirin use in childhood acute ischemic stroke, includes a summary of aspirin pharmacology to highlight misconceptions and common clinical situations which may limit its efficacy, and discusses the techniques and potential role of laboratory monitoring of aspirin efficacy in children.

High acetylsalicylic acid dosing in infants after modified Blalock-Taussig shunt

OBJECTIVE

Shunt-related adverse events are frequent in infants after modified Blalock-Taussig despite use of acetylsalicylic acid prophylaxis. A higher incidence of acetylsalicylic acid-resistance and sub-therapeutic acetylsalicylic acid levels has been reported in infants. We evaluated whether using high-dose acetylsalicylic acid can decrease shunt-related adverse events in infants after modified Blalock-Taussig.

METHODS

In this single-centre retrospective cohort study, we included infants ⩽1-year-old who underwent modified Blalock-Taussig placement and received acetylsalicylic acid in the ICU. We defined acetylsalicylic acid treatment groups as standard dose (⩽7 mg/kg/day) and high dose (⩾8 mg/kg/day) based on the initiating dose.

RESULTS

There were 34 infants in each group. Both groups were similar in age, gender, cardiac defect type, ICU length of stay, and time interval to second stage or definitive repair. Shunt interventions (18 versus 32%, p=0.16), shunt thrombosis (14 versus 17%, p=0.74), and mortality (9 versus 12%, p=0.65) were not significantly different between groups. On multiple logistic regression analysis, single-ventricle morphology (odds ratio 5.2, 95% confidence interval of 1.2-23, p=0.03) and post-operative red blood cells transfusion ⩾24 hours [odds ratio 15, confidence interval of (3-71), p&lt;0.01] were associated with shunt-related adverse events. High-dose acetylsalicylic acid treatment [odds ratio 2.6, confidence interval of (0.7-10), p=0.16] was not associated with decrease in these events.

CONCLUSIONS

High-dose acetylsalicylic acid may not be sufficient in reducing shunt-related adverse events in infants after modified Blalock-Taussig. Post-operative red blood cells transfusion may be a modifiable risk factor for these events. A randomised trial is needed to determine appropriate acetylsalicylic acid dosing in infants with modified Blalock-Taussig.

Antiplatelet Effect of Ketorolac in Children After Congenital Cardiac Surgery

Background:

Ketorolac is used for pediatric analgesia after surgery despite its known platelet inhibition via the arachidonic acid (AA) pathway. The degree of platelet inhibitory effect after cardiac surgery is not well characterized. Thromboelastography with platelet mapping (TEG-PM) is emerging as a frequently used test to evaluate platelet inhibition via the AA pathway.

Methods:

Post hoc analysis of a data set collected in a prospective observational cohort study evaluating platelet inhibition in children after congenital heart surgery with cardiopulmonary bypass (CPB). Categorization into two groups: (1) received ketorolac and (2) did not receive ketorolac for analgesia after surgery. The TEG-PM was evaluated at two time points (prior to surgery and 12-48 hours after CPB).

Results:

Fifty-three children were studied; mean age was 6.6 (range: 0.07-16.7) years and 45% (n = 24) were female. Participants were distributed into two groups by ketorolac use, 41 within the ketorolac group and 12 in the no ketorolac group. All 41 participants who received ketorolac had platelet inhibition and 11 (91.7%) of 12 participants who did not receive ketorolac had normal platelet function after surgery ( P < .0001). There was no difference in patient characteristics or clinical data between the two groups.

Conclusions:

Ketorolac use in a cohort of children after congenital cardiac surgery was associated with platelet inhibition via the AA pathway when evaluated by TEG-PM.