Snapshot A 55-year-old man presents to the emergency room after collapsing while hiking. His hiking group reports that he had not had any water to drink as he was nauseous from food poisoning the night before when he had copious amounts of diarrhea. His blood pressure is 85/53 mmHg. On physical exam, he has no jugular venous distention, his mucous membranes are dry and skin is cold and clammy with reduced skin turgor. He is given fluids. (Hypovolemic shock) Introduction Clinical definition shock secondary to ↓ intravascular volume Etiology Hemorrhagic trauma gastrointestinal bleeding ruptured aneurysm or hematoma fistula post-partum hemorrhage Non-hemorrhagic gastrointestinal fluid losses skin losses (e.g., burns or Stevens-Johnson syndrome) renal losses third space losses Pathogenesis an underlying event causes ↓ intravascular volume ↓ intravascular volume → ↓ cardiac output (CO) + wedge pressure and compensatory ↑ systemic vascular resistance (SVR) Presentation Symptoms typically present with features of the underlying cause Physical exam hypotension tachycardia reduced skin turgor nondistended jugular veins dry mucous membranes cold and clammy skin Imaging Imaging as needed to identify the underlying cause Studies Pulmonary artery catheterization findings ↓ pulmonary capillary wedge pressure (PCWP < 15 mmHg) ↓ cardiac output as severity progresses ↑ systemic vascular resistance Making the diagnosis most cases are clinically diagnosed Differential Different Types of ShockShock TypeSkinWedge Pressure (PCWP) (Preload)Systemic Vascular Resistance (SVR) (Afterload)Cardiac OutputHyovolemic Cold and clammy skin ↓↓ ↑ ↓Cardiogenic↑↑↓Obstructive ↑ or ↓ ↑ ↔ or ↓↓Distributive Warm or dry skin ↔ or ↓ ↓↓ ↓ or ↑ Treatment Management approach treat the underlying cause establish the ABCs - airway, breathing, and circulation Medical intravenous fluids with large-bore IVs indications for all patients transfuse blood for hemorrhagic shock Complications Acute renal failure