Overview Different Types of Shock Shock Type Skin Wedge Pressure (PCWP) (Preload) Systemic Vascular Resistance (SVR) (Afterload) Cardiac Output Hypovolemic Cold and clammy skin ↓↓ ↑ ↓ Cardiogenic Cold and clammy skin ↑ or ↓ ↑ ↓↓ Obstructive Cold and clammy skin ↑ or ↓ ↑ ↓↓ Distributive Warm or dry skin ↓ ↓↓ ↓ (dry)↑ (warm) Introduction Clinical definition decreased oxygen delivery, increased oxygen consumption, or impaired oxygen utilization that results in cellular and tissue hypoxia this occurs in cases of reduced tissue perfusion (e.g., hemorrhage) there are 4 types of shock cardiogenic hypovolemic distributive obstructive Cardiogenic Clinical definition shock secondary to intracardiac causes results in a decreased cardiac output self-perpetuating since hypotension will result in decreased perfusion to the coronary vessels thus worsening ischemia decreased stroke volume will in turn increase the amount of blood in the left ventricle (LV) which increases LV size and thus myocardial oxygen demand Etiology causes of cardiogenic shock can be divided into three categories cardiomyopic myocardial infarction (e.g., > 40% of the LV mass is infarcted) heart failure exacerbations (e.g., dilated cardiomyopathy) myocarditis stunned myocardium in the setting of prolonged ischemia drug induced (e.g., β-blockers) arrhythmic tachyarrhythmias (e.g., atrial fibrillation) bradyarrhythmias (e.g., Mobitz type II second degree heart block) mechanical valvular pathology (e.g., valvular rupture, insufficiency, and severe stenosis) atrial myxoma Clinical findings cold and clammy skin Treatment intravenous inotropes (e.g., dobutamine) intra-aortic balloon pump in certain cases percutaneous left ventricular assist device (LVAD) in cases where more extensive and prolonged support is needed to achieve hemodynamic stability Hypovolemic Clinical definition shock secondary to reduced intravascular volume the reduced preload results in a decreased cardiac output Etiology causes of hypovolemic shock can be divided into hemorrhagic (e.g., trauma and gastrointestinal bleeding) non-hemorrhagic decreased intravascular volume not due to loss of blood gastrointestinal losses (e.g., diarrhea) skin loss (e.g., heat stroke and burns) Clinical findings cold and clammy skin Treatment intravenous fluids Distributive Clinical definition shock secondary to severe peripheral vasodilation Etiology septic shock presents with decreased vasopressin levels non-septic causes include systemic inflammatory response syndrome (SIRS) neurogenic shock (e.g., traumatic brain and spinal cord injury and neuro-axial anesthesia) anaphylaxis Clinical findings warm or dry skin Treatment intravenous fluids and vasopressors in patients with septic shock and hypotension refractory to fluids and vasopressors, adrenal insufficiency should be suspected and treated empirically with hydrocortisone Obstructive Clinical definition shock secondary to extracardiac causes of pump failure (most common) typically is associated with impaired right ventricular output Etiology causes of obstructive shock can be divided into pulmonary vascular (e.g., severe pulmonary embolism and pulmonary hypertension) mechanical (e.g., tension pneumothorax, pericardial tamponade, and constrictive pericarditis Clinical findings cold and clammy skin Treatment manage the obstruction