Systemic-to-pulmonary artery shunts are amongst the most common palliative procedures performed in neonates with congenital heart defects. These procedures require immediate postoperative thromboprophylaxis to prevent life-threatening shunt thrombosis. The novel use of intravenous P2Y12 platelet receptor antagonists has led to a need for dosing recommendations and monitoring. This study aims to determine cangrelor dosing in neonates through laboratory assessment of P2Y12 receptor reactivity and adverse events.
Observational retrospective cohort study on the use of cangrelor for thromboprophylaxis in the immediate postoperative period of neonates undergoing placement of systemic-to-pulmonary artery shunts in a tertiary children's hospital from March 2020 to March 2021.
Ten neonates receiving cangrelor post systemic-to-pulmonary artery shunt placement were included in the study. Median age and weight were 4 days (IQR, 2.75–5.25) and 3.49 kg (IQR, 3.1–3.75), respectively. Five (50%) patients received a 3.5-mm shunt, while the remaining patients received a 4-mm shunt. For thrombin inhibition, 5 (50%) patients received heparin and 5 (50%) received bivalirudin. Median cangrelor dose was 0.1 mcg/kg/min (IQR, 0.1–0.1). Median achieved P2Y12 reaction units (PRU) at this cangrelor dose was 127.5 (IQR, 72.5–173.75). No shunt thrombosis occurred in these patients; however, there was 1 minor hemorrhagic event.
Our study suggests that a cangrelor dose of 0.1 mcg/kg/min is associated with therapeutic PRU and prevents shunt thrombosis in neonates post systemic-to-pulmonary artery shunt, with minimal hemorrhagic complications.