1Servico of Anesthesiology, Hospital of Porto, Largo Professor Abel Salazar, 4099-001 Porto, Portugal
2Servico of Clinical Hematology, Hospital of Porto, Largo Professor Abel Salazar, 4099-001 Porto, Portugal
*Corresponding Author:
Humberto Machado, Servico of Anesthesiology, Hospital of Porto, Largo Professor Abel Salazar, 4099-001 Porto, Portugal, Tel: +351 935848 Email: