Đo cung lượng tim tim IS đầu ra hữu ích như một trợ giúp chẩn đoán và theo dõi Cả hai điều trị ở bệnh nhân bị bệnh nặng. Một đầu ra thấp tim ở bệnh nhân hạ huyết áp với sốc tim bao gồm IS và Cho biết Cần hỗ trợ co cơ, trong khi một cú sốc tim tự hoại với sản lượng cao bao gồm IS. | Cardiac output Measurement of cardiac output is useful both as a diagnostic aid and to monitor therapy in the critically ill patient. A low cardiac output in the hypotensive patient is consistent with cardiogenic shock and indicates the need for inotropic support while a high cardiac output is consistent with septic shock. SVR In the clinical setting the determination of SVR is often used together with cardiac output and PAOP to assist in the diagnosis of the shocked patient Table . A low SVR is characteristic of septic shock while the SVR is usually raised in cardiogenic shock and hypovolaemia. Serial measurements of PAOP cardiac output and SVR can be used to monitor the effects of fluid administration and inotropic therapy. Blood oxygen saturations The differential diagnosis of the patient in cardiogenic shock after acute myocardial infarction includes VSD and mitral regurgitation due to papillary muscle rupture. Differentiating between the two may be difficult because both cause similar clinical presentations and a pansystolic murmur. If the diagnosis cannot be made by echo then blood oxygen saturations can be measured from the right ventricle and right atrium. A step-up in oxygen saturation in the right ventricle oxygen saturation higher than the right atrium would be consistent with a VSD. Mixed venous pulmonary artery blood oxygen saturation measurement is required for estimation of cardiac output by the Fick method. Cardiovascular System Table The differential diagnosis of shock using haemodynamic parameters obtained from Swan-Ganz catheterisation PAOP Cardiac index SVR Hypovolaemia ị ị T Cardiogenic shock T ị T Septic shock ị T ị PAOP pulmonary artery occlusion pressure SVR systemic vascular resistance Normal values PCWP 8-12 mmHg Cardiac index l min m2 SVR 770-1500 dynes s cm5 SCC pp 18-20 Vivas Key Questions in Surgical Critical Care 161 9. 9. Cardiovascular System What are the complications of blood transfusion The possible complications
