An acute obstruction of blood flow in central vessels of the systemic or pulmonary circulation causes the clinical symptoms of shock accompanied by disturbances of consciousness, centralization, oliguria, hypotension and tachycardia. In the case of an acute pulmonary embolism an intravascular occlusion results in an acute increase of the right ventricular afterload. In the case of a tension pneumothorax, an obstruction of the blood vessels supplying the heart is caused by an increase in extravascular pressure. From a hemodynamic viewpoint circulatory shock caused by obstruction is closely followed by cardiac deterioration; however, etiological and therapeutic options necessitate demarcation of cardiac from non-cardiac obstructive causes. The high dynamics of this potentially life-threatening condition is a hallmark of all types of obstructive shock. This requires an expeditious and purposeful diagnosis and a rapid and well-aimed therapy.