**2. Definition of V-A ECMO**

Extracorporeal membrane oxygenation is essentially a modification of the cardiopulmonary bypass circuit, which is used routinely in cardiac surgery. Blood is removed from the venous system, oxygenated by an oxygenator and then returned back to the body by a pump. ECMO provides both full cardiac and respiratory support. In brief, every ECMO system is basically a closed tubing loop with the interpolation of a blood pump (centrifugal or roller) and an oxygenator. Two vessel cannulas complete the system. Technically the ECMO system is more complex and several configurations have been developed according to the primary etiology.

**c.** a cardiac index less than 1.8 L/min/m2 without inotropic support and 2.0–2.2 L/min/m2

Veno-Arterial Extracorporeal Membrane Oxygenation for Refractory Cardiogenic Shock and Cardiac Arrest

http://dx.doi.org/10.5772/54719

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**d.** high left ventricular (LV) filling pressures (pulmonary capillary wedge pressure more

**b.** alteration in mental status such delirium, confusion, clouded sensorium, psychomotor

**f.** hyperlactacidemia (more than 3.mmol/L) as expression of impaired peripheral microcir‐

Cardiac arrest is a major cause of unexpected death in developed countries with a low probability of patient survival. Survival is influenced by several variables common to both inhospital and out-of-hospital arrest, such as time to recognition of the cardiac arrest, time to initiation of CPR, rhythm presentation, first defibrillation [2, 11, 12]. In current resuscitation guidelines for in-hospital cardiac arrest (IHCA) patients [13], CPR using ECMO (E-CPR) has been assigned a low-grade recommendation. It is reported that ECMO for out-of-hospital cardiac arrest (OHCA) has worse outcomes compared with ECMO for IHCA patients [7, 14]. In the United States, more than 166,000 patients experience an OHCA annually [15] and approximately 60% are treated by emergency medical services. OHCA survival to hospital discharge range from 0.3% in Detroit [16] to 20.4% in Slovenia [17].Five clinical criteria to predict survival from OHCA [18] have recently been reported. They are: cardiac arrest witnessed by a bystander, arrest witnessed by emergency medical personnel, provision of bystander CPR, shockable cardiac rhythm, and return of spontaneous circulation (ROSC) in

Patient selection is a crucial point when the physician needs to take the decision to institute ECMO and several considerations must be focused up. Most importantly, it must be consider

with inotropic and intra-aortic balloon pump (IABP) support;

**3. Definition of in-hospital and out-hospital cardiac arrest**

End-organ hypoperfusion may be manifested clinically by:

**c.** decreased urine output (less than 1 ml/kg/min);

**g.** mixed venous saturation of less than 65%.

the field. These criteria are applicable on IHCA too.

**4. Indication and contraindications for v-a ECMO**

than 18 mmHg).

agitation;

**e.** tachycardia;

culation;

**a.** pale, cool, and clammy peripheries;

**d.** pulmonary congestion or edema;

The veno-arterial ECMO configuration is a tubing loop with a venous arm connected to a venous cannula to allow the venous blood drainage and an arterial arm to return back the oxygenated blood inside the patient's circulatory system. This mode provides both cardiac and respiratory support and can be achieved by either peripheral or central cannulation (Figure1).

**Figure 1.** Patient supported with peripheral V-A ECMO

The veno-venous ECMO mode refers to blood, which is drained from the venous system and returned back to the venous system. This mode only provides respiratory support and is obtained by peripheral cannulation, usually of both femoral veins and jugular vein. This ECMO configuration will be not discussed in this chapter.

#### **2.1. Definition of cardiogenic shock**

Cardiogenic shock is a state of impaired and non-physiologic end-organ perfusion owing to a low cardiac output. Being characterized by hypotension cardiogenic shock is defined mainly by haemodynamic parameters as follows [9,10]:


End-organ hypoperfusion may be manifested clinically by:


**2. Definition of V-A ECMO**

274 Principles and Practice of Cardiothoracic Surgery

**Figure 1.** Patient supported with peripheral V-A ECMO

**2.1. Definition of cardiogenic shock**

by haemodynamic parameters as follows [9,10]:

ECMO configuration will be not discussed in this chapter.

(Figure1).

Extracorporeal membrane oxygenation is essentially a modification of the cardiopulmonary bypass circuit, which is used routinely in cardiac surgery. Blood is removed from the venous system, oxygenated by an oxygenator and then returned back to the body by a pump. ECMO provides both full cardiac and respiratory support. In brief, every ECMO system is basically a closed tubing loop with the interpolation of a blood pump (centrifugal or roller) and an oxygenator. Two vessel cannulas complete the system. Technically the ECMO system is more complex and several configurations have been developed according to the primary etiology.

The veno-arterial ECMO configuration is a tubing loop with a venous arm connected to a venous cannula to allow the venous blood drainage and an arterial arm to return back the oxygenated blood inside the patient's circulatory system. This mode provides both cardiac and respiratory support and can be achieved by either peripheral or central cannulation

The veno-venous ECMO mode refers to blood, which is drained from the venous system and returned back to the venous system. This mode only provides respiratory support and is obtained by peripheral cannulation, usually of both femoral veins and jugular vein. This

Cardiogenic shock is a state of impaired and non-physiologic end-organ perfusion owing to a low cardiac output. Being characterized by hypotension cardiogenic shock is defined mainly

**a.** a systolic blood pressure of less than 90 mmHg for more than 30 min with normovolemia;

**b.** the need of inotropic drugs to obtain a systolic blood pressure more than 90 mmHg with;

