Current Practice Patterns of Phamacological Thromboprophylaxis for Prevention of Venous Thromboembolism in Hospitalized Children: A Survey of Pediatric Hemostasis and Thrombosis Experts in North America

Background:

The prevalence of venous thromboembolism (VTE) is on the rise in critically sick hospitalized children. It is one of the most common hospital acquired complications (HAC) and Joint Commission for Accreditation for Hospitals (JCAHO) has mandated to develop institutional guidelines to prevent VTE. It is recommended to use pharmacologic thromboprophylaxis (PTP), the most effective intervention for VTE prevention, for eligible adult population. Unfortunately this strategy is not systematically evaluated in children due to sample size and recruitment issues. Therefore the risks and benefits of universal PTP in critically sick children are unclear specifically in the context of exposure to acquired risk factors including central venous lines (CVLs), age, cancer, infection and trauma/surgery. We sought to understand expert clinical decision-making.

Aims:

To understand the current practice patterns of pharmacological thromboprophylaxis and the perceived risks of VTE in hospitalized children.

Methods:

This cross-sectional self-administered multiple-choice survey questionnaire was administered to pediatric hematologists who are members of Hemostasis Thrombosis Research Society (HTRS) with at least 5 years of experience. The survey designed to collect physicians’ demographics, thromboprophylaxis policies and opinions about the use of PTP using 13 multiple choice questionnaire and 4 clinical scenarios.

Results:

The response rate was 47.3% [53/112]. Majority practiced at University affiliated hospitals (73%). Only 44% of respondents were in favor of adoption of universal PTP policy for children and 65% of them didn’t support thromboprophylaxis for CVL. Only one third of the participants had established policy for PTP mainly for intensive care unit, orthopedic and trauma patients.

Almost all respondents (98 %) used PTP for a select patient population based on following risk factors: known inherited thrombophilia, morbid obesity, chronic inflammatory condition, history of idiopathic deep venous thrombosis (DVT), CVL related DVT, detected antiphospholipid antibody and teenagers with DVT risk factors. The factors that were not important for thromboprophylaxis included: underlying malignancy, positive blood culture, diabetic ketoacidosis, immobilization and CVLs, whether being critically sick newborns or not. Four different adolescent, child, and infant scenarios were answered by 94 % of respondents.

Case (1) A newborn on mechanical ventilation with sepsis, thrombocytopenia and femoral line dysfunction without CVL-thrombosis. About 72% of respondents didn’t consider AC, 68% of them didn’t consider mechanical thromboprophylaxis. If developed MRSA sepsis and right hip osteomyelitis later on, only 42% of all respondents would not consider AC. So, in the newborns, PTP may not benefit for CVL malfunction but may be beneficial in the setting of osteomyelitis. LMWH was the preferred choice of PTP.

Case (2): A 10 years old boy with a fracture femur with 4 weeks immobilization, 66 % of respondents were not in favor of AC, 69 % of them would consider mechanical thromboprophylaxis. So, Mechanical thromboprophylaxis was preferred over PTP in orthopedic patients.

Case (3): An overweight teenager girl with Down syndrome on mechanical ventilation for pneumonia and receiving mechanical thromboprophylaxis, 46% of all respondents considered AC and only 34% of them would continue AC post-discharge. If she has been on oral contraceptive pills (OCPs), 68% would prescribe TPT. So, PTP in critically ill teenagers is equipoise even with overweight and immobilization. OCPs were perceived as important risk factor for VTE.

Case (4): A child with ALL who had an acute stroke following induction chemotherapy including Asparginase, 82% of all respondents would consider AC for re-induction regimen containing Asparginase. So, PTP is recommended in children with ALL and Asparginase related strokes if re-exposed.

Conclusions:

The results of survey revealed that despite concerns about rising VTE prevalence, there is equipoise about the adoption of a universal PTP policy for children. Experts take into consideration multiple risk factors when deciding about primary thromboprophylaxis. The variability in clinical thromboprophylaxis practices highlights the need for rigorous prospective randomized trials so as to develop evidence-based VTE prevention strategies for children.