Open-heart surgery in von Willebrand's disease

Perioperative blood transfusion and blood conservation in cardiac surgery: the Society of Thoracic Surgeons and The Society of Cardiovascular Anesthesiologists clinical practice guideline

BACKGROUND

A minority of patients having cardiac procedures (15% to 20%) consume more than 80% of the blood products transfused at operation. Blood must be viewed as a scarce resource that carries risks and benefits. A careful review of available evidence can provide guidelines to allocate this valuable resource and improve patient outcomes.

METHODS

We reviewed all available published evidence related to blood conservation during cardiac operations, including randomized controlled trials, published observational information, and case reports. Conventional methods identified the level of evidence available for each of the blood conservation interventions. After considering the level of evidence, recommendations were made regarding each intervention using the American Heart Association/American College of Cardiology classification scheme.

RESULTS

Review of published reports identified a high-risk profile associated with increased postoperative blood transfusion. Six variables stand out as important indicators of risk: (1) advanced age, (2) low preoperative red blood cell volume (preoperative anemia or small body size), (3) preoperative antiplatelet or antithrombotic drugs, (4) reoperative or complex procedures, (5) emergency operations, and (6) noncardiac patient comorbidities. Careful review revealed preoperative and perioperative interventions that are likely to reduce bleeding and postoperative blood transfusion. Preoperative interventions that are likely to reduce blood transfusion include identification of high-risk patients who should receive all available preoperative and perioperative blood conservation interventions and limitation of antithrombotic drugs. Perioperative blood conservation interventions include use of antifibrinolytic drugs, selective use of off-pump coronary artery bypass graft surgery, routine use of a cell-saving device, and implementation of appropriate transfusion indications. An important intervention is application of a multimodality blood conservation program that is institution based, accepted by all health care providers, and that involves well thought out transfusion algorithms to guide transfusion decisions.

CONCLUSIONS

Based on available evidence, institution-specific protocols should screen for high-risk patients, as blood conservation interventions are likely to be most productive for this high-risk subset. Available evidence-based blood conservation techniques include (1) drugs that increase preoperative blood volume (eg, erythropoietin) or decrease postoperative bleeding (eg, antifibrinolytics), (2) devices that conserve blood (eg, intraoperative blood salvage and blood sparing interventions), (3) interventions that protect the patient's own blood from the stress of operation (eg, autologous predonation and normovolemic hemodilution), (4) consensus, institution-specific blood transfusion algorithms supplemented with point-of-care testing, and most importantly, (5) a multimodality approach to blood conservation combining all of the above.

Closure of a ventricular septal defect in a patient with von Willebrand disease

Few reports of open heart surgery being performed in patients with von Willebrand disease (vWD) have been documented. We describe herein the case of a 5-year-old girl with a ventricular septal defect (VSD) and vWD who underwent patch closure under cardiopulmonary bypass (CPB). The hematological parameters relating to vWD, namely, factor VIII, von Willebrand factor, and factor VIII-related antigen were monitored perioperatively. These laboratory findings were elevated after the termination of CPB, and consistently maintained within the normal range for 4 months postoperatively. The operation was successfully completed without the administration of factor VIII concentrates or homologous blood products.

Coronary artery bypass in idiopathic thrombocytopenia without splenectomy

A patient with coronary artery disease and idiopathic thrombocytopenia purpura underwent coronary artery bypass grafting without splenectomy. Our experience indicates that use of cardiopulmonary bypass in patients with idiopathic thrombocytopenic purpura does not invariably mandate splenectomy.

Major surgery in von Willebrand's disease

Two patients with von Willebrand's disease underwent major surgery, the first had aortic valve replacement and the second a total hip replacement. Clinically, the best practical test for monitoring the dose of cryoprecipitate necessary to maintain haemostasis was the bleeding time. The response to coagulation factor replacement in von Willebrand's disease is extremely variable, and it is necessary to maintain close coagulation monitoring until the patient's surgical condition is satisfactory for discharge from hospital.

Cardiovascular surgery in patients with congenital plasma coagulopathies

From 1978 to 1986, fifteen cardiovascular operations were performed on 13 patients with known congenital bleeding disorders. The patients (10 men and 3 women) had a mean age of 51.1 +/- 3.4 years. Four were seen with cardiovascular lesions and documented hemophilia A (Factor VIII deficiency); 3 had hemophilia B (Factor IX deficiency); 3 had Factor XI deficiency; 2 had von Willebrand's disease, and 1 had dysfibrinogenemia. All patients had a history of major hemorrhage after dental extractions or general surgical procedures, and had clearly documented coagulation disorders on hematological evaluation. Elective cardiovascular procedures performed in these patients included aortocoronary bypass grafting (eight), cardiac valve replacement or repair (five), aortic graft placement (one), and carotid endarterectomy (one). The mainstay of perioperative management included appropriate replacement therapy with blood components. Coagulation factor levels were measured routinely to guide therapy. There were no deaths. Two hemorrhagic complications necessitated reexploration. We conclude that in patients known to have congenital coagulation disorders, cardiovascular operations using systemic heparinization can be performed with minimal morbidity and mortality when carried out with preoperative and perioperative support from the hematology service, adequate replacement therapy using blood components, and careful monitoring of the coagulation status.

Aortic valve replacement in a patient with von Willebrand's disease

Few cases have been reported to date of cardiac surgery performed on patients with von Willebrand's disease. This report details the management of such a patient, who underwent aortic valve replacement for severe calcific aortic stenosis.

Anesthesia and postoperative care for cardiac operations

Almost three decades have passed since the establishment of open-heart surgery, and in such a short life span the specialty has established itself scientifically and reached a certain maturity. New techniques, better understanding of the pathophysiology of cardiac problems, and the effective use of new drugs constantly improve the results of operation. Greater experience in anesthetic management and improved postoperative care will contribute much to the success of this youngest surgical specialty. This review outlines the current principles of anesthesia and postoperative care of patients undergoing cardiac operations. Preanesthetic evaluation provides guidance for anesthetic management, supportive techniques, and postoperative care. During operations, light anesthesia is usually sufficient for patients with cardiac disease and minimizes myocardial depression. Monitoring must provide data on the physiological changes that are taking place from moment to moment during and after operations. Perfusion produces a highly abnormal state, and the severity of complications varies with its duration. Introduction of new drugs has also facilitated hemodynamic management during and after operations. Postoperative care is based on careful observation of the patient and early detection of trends, both of which lead to preventive rather than curative treatment wheneven possible.