Coagulation and the surgical neonate

Abstract

Both coagulopathy and abnormal thrombosis can complicate the anesthetic and surgical management of neonatal patients; however, the patterns of bleeding and thrombosis in neonates differ from those in adults or older children. Severe coagulopathic bleeding most commonly occurs during heart surgery and almost certainly contributes to morbidity and mortality in this population. Such severe bleeding is rare during other surgery; the exception is babies presenting to the operating room with established coagulopathy secondary to severe sepsis. Alternatively, pathological thrombosis will mainly occur in association with indwelling vascular access devices or surgically created vascular shunts. There are important differences between the coagulation system in neonates and older patients. The implication of this is that therapies established in other patient groups will not be optimal for neonates without adaptation. While evidence from high-quality clinical trials is rarely available, an understanding of how coagulation in neonates differs can help to guide practice. This review will discuss important differences between the coagulation system of neonates and older patients and how these relate to newer models of coagulation. The emphasis will be on issues likely to impact on perioperative care. In particular, the management of severe bleeding, the manipulation of coagulation during heart surgery, and the management of coagulopathy in septic neonates will be discussed in detail.

Guidelines on transfusion for fetuses, neonates and older children

“…This large but observational study was limited by the lack of data on comparative dosing. Overall, UK paediatric cardiac surgery practice in the use of antifibrinolytics is variable due to a persisting lack of clarity on appropriate dosing (Arnold, ).…”

Thoracoabdominal and General Surgery

“…Few would hesitate to transfuse platelets if the platelet count was <50,000/mm 3 preoperatively. Prothrombin time (PT) and partial thromboplastin time (APTT) vary during the neonatal period, being prolonged immediately after birth due to reduced procoagulants and then decrease toward normal childhood values throughout the neonatal period [ 5 ]. Fresh frozen plasma (FFP) 15 ml/kg is recommended if the prothrombin time (PT) or activated partial thromboplastin time (APTT) ratio is >1.5 times normal.…”

“…Thrombocytopenia is common, particularly in neonates with sepsis, and should be corrected before undertaking surgery. Platelet concentrations <150,000/mm 3 are considered abnormal in neonates in many centers, but surgical bleeding is uncommon when the count is >50,000/mm 3 [ 5 ]. A platelet transfusion consisting of 10-20 ml/kg should be considered if the platelet count is <100 × 10 9 /l before surgery, although in the case of necrotizing enterocolitis (NEC), the platelet count is often <100,000/mm 3 preoperatively and platelet transfusions have not been shown to be benefi cial in the absence of bleeding [ 6 ].…”

Management of fluids in neonatal surgery

“…In a recent review, Arnold recommends aiming for >1 g dl À1 initially, but setting the threshold at >2 g dl À1 if bleeding subsequently continues. 16…”