1. Audit of Blood Product Use in Paediatric Cardiac Bypass Surgery.
Dr J. P. R. Brown & Dr I. Jenkins.
Department of Anaesthesia, The Royal Bristol Children’s Hospital.
Introduction:
Cardiopulmonary bypass (CPB) associated coagulopathy is multi-factorial [1]; consumption through activation (bypass circuit, surgery), anticoagulation, hypofibrinogenaemia, hypothermia, dilution & aspirin. Paediatric practice brings specific challenges: increased dilution from a relatively greater volume of CPB prime, immature coagulation & specific defects in cyanotic disease. Higher postoperative (postop) chest drain outputs are associated with increased morbidity & mortality. These are reduced by correction of CPB related coagulopathy. There is variation in current practice & debate as to what represents best practice. The aim was to investigate anaesthetic perioperative management of CPB related coagulopathy, to inform recommendations & develop an agreed departmental consensus. Ultimately aiming to optimise patient outcome.
Discussion:
Administration of blood products has associated risks. They are a scarce, expensive resource. Rationale for exposing patients to them must be justified. Judicious use of clotting products will reduce transfusion of packed red cells and their associated risks. Some products, depending on volume (Plts & cryoprecipitate) are pooled. Reduction in exposure to different donors is a priority. In paediatric practice administration of cryoprecipitate may have advantages over FFP [3]. Identifying those most at risk of haemorrhage following CPB will allow appropriate targeting of therapy to those most likely to benefit & reduce unnecessary exposure. Risk factors indentified by this audit for increased drain output are in keeping with those described in the literature [1,3].
Methods:
Case notes review. Target: analyze 50 consecutive cases. Demographic data was recorded. Surgical operations were categorised as complex or simple. Data collection was divided into stages:
• Preoperative (Presence of cyanotic heart disease or on aspirin therapy. Emergency or redo case.)
• Intraoperative (Details of prime volume, CPB time & temperature cooled to, blood products given, ACT result)
• Postoperative (Coagulation blood tests, blood products given & chest drain output (first 12 hours postop).
Audit standards described below.
Results:
57 CPB cases.
72% Complex Operations. 3 Surgeons. 5 Anaesthetists.
Audit Standards:
To achieve 100% in the postoperative period: Achievement
Chest Drain Output Less than 10 mls/kg in first 12 hour 70%
To Measure Platelets (Plts) / INR / APTTR %
Activated Clotting Time (ACT) 89%
Fibrinogen (Fib) %
To Achieve [2] Plts> 100, ACT<140 , INR/APTTR<1.5, Fib >1 79%
Blood product replacement None in first 12 hours 79%
13 different combinations of intraoperative products (Plts, cryoprecipitate, FFP, tranexamic acid) were recorded. Mean drain output post operatively was 8 mls/kg . Those not given intraoperative products (13/57) had a mean of 6mls/kg drain loss, only 1 of these required products postop. Those receiving postop products:
FFP (7/57) – 85% < 6 months old, 66% Cyanotic Heart Disease
Plts (5/57)– 80% Cyanotic Heart Disease, 40% Preop Aspirin Therapy
Ages
Recommendations:
All paediatric CPB patients:
•should receive tranexamic acid intraoperatively.
•should have fibrinogen & platelets measured intraoperatively, post protamine administration.
•if stratified as low risk should not receive products intraoperatively
•if stratified as high risk should have platelets & fibrinogen available intraoperatively.
Consideration should be made to forwarding a business case for near patient testing (TEG®, ROTEM®).
LOW RISK:
Surgery
Simple Operation
Patients
> 18 months old
CPB
> 30oC
< 120 mins
HIGH RISK:
Patients
On aspirin
Cyanotic Heart Disease
< 6 months old
> 2 RFs
CPB
< 20oC
> 120 mins
References:
Eaton MP, Iannoli EM. Coagulation considerations for infants and children undergoing cardiopulmonary bypass. Review article. Pediatric Anesthesia 2011; 21: 31-42
British Committee for Standards in Haematology. Guidelines on the management of massive blood loss. British Journal of Haematology 2006; 135:
Miller BE, Mochizuki T, Levy JH, Bailey JM, Tosone SR, Tam VKH, Kanter KR. Predicting and treating coagulopathies after cardiopulmonary bypass in children. Anesthesia and Analgesia 1997; 85: