The annual incidence of shock of any etiology is 0.3 to 0.7 per 1000, with hemorrhagic shock being most common in the intensive care unit.<unk>  is the most common type of shock in children, most commonly due to diarrheal illness in the developing world.<unk>  occurs as a result of either blood loss or extracellular fluid loss. Blood loss Hemorrhagic shock is<unk>  from blood loss. Traumatic injury is by far the most common cause of hemorrhagic shock, particularly blunt and penetrating trauma, followed by upper and lower gastrointestinal sources, such as gastrointestinal (GI) bleed. Other causes of hemorrhagic shock include bleed from an ectopic pregnancy, bleeding from surgical intervention, vaginal bleeding, and splenic rupture. Obstetrical, vascular, iatrogenic, and even urological sources have all been described. Bleeding may be either external or internal. A substantial amount of blood loss to the point of hemodynamic compromise may occur in the chest, abdomen, or the retroperitoneum. The thigh itself can hold up to 1 L to 2 L of blood. Localizing and controlling the source of bleeding is of utmost importance to the treatment of hemorrhagic shock. The sequence of the most-commonly-seen causes that lead to hemorrhagic type of<unk>  is given in order of frequencies: blunt or penetrating trauma including multiple fractures absent from vessel impairment, upper gastrointestinal bleeding e.g., variceal hemorrhage, peptic ulcer., or lower GI bleeding e.g., diverticular, and arteriovenous malformation. Except for the two most common causes, the less common causes are intra-operative and post-operative bleeding, abdominal aortic rupture or left ventricle aneurysm rupture, aortic–enteric fistula, hemorrhagic pancreatitis, iatrogenic e.g., inadvertent biopsy of arteriovenous malformation, severed artery., tumors or abscess erosion into major vessels, post-partum hemorrhage, uterine or vaginal hemorrhage owing to infection, tumors, lacerations, spontaneous peritoneal hemorrhage caused by bleeding diathesis, and ruptured hematoma. Fluid loss In spite of hemorrhage, the amount of circulating blood in the body may drop as well when one loses excessive body fluid owing to non-hemorrhagic reasons.<unk>  as a result of extracellular fluid loss can be of the 4 etiologies. Gastrointestinal Gastrointestinal (GI) losses can occur via many different etiologies. The gastrointestinal tract usually secretes between 3 and 6 liters of fluid per day. However, most of this fluid is reabsorbed as only 100 to 200 mL are lost in the stool. Volume depletion occurs when the fluid ordinarily secreted by the GI tract cannot be reabsorbed. This occurs when there is retractable vomiting, diarrhea, or external drainage via stoma or fistulas. Kidneys Renal losses of salt and fluid can lead to<unk> . The kidneys usually excrete sodium and water in a manner that matches sodium intake and water intake. Diuretic therapy and osmotic diuresis from hyperglycemia can lead to excessive renal sodium and volume loss. In addition, there are several tubular and interstitial diseases beyond the scope of this article that cause severe salt-wasting nephropathy. Skin Fluid loss also can occur from the skin. In a hot and dry climate, skin fluid losses can be as high as 1 to 2 liters/hour. Patients with a skin barrier interrupted by burns or other skin lesions also can experience large fluid losses that lead to<unk> . Third-spacing Sequestration of fluid into a third space also can lead to volume loss and<unk> . Third-spacing of fluid can occur in intestinal obstruction, pancreatitis, obstruction of a major venous system, vascular endothelium or any other pathological condition that results in a massive inflammatory response.
Hypovolemic shock
Obstructive shock
Distributive shock
Neurogenic shock
Cryptic shock
Septic shock
Spinal shock
Vasodilatory shock