Читать книгу Managing Medical and Obstetric Emergencies and Trauma - Группа авторов - Страница 102

This form of shock is due to a drop in the effective circulating volume resulting in a decrease in venous return. This causes a drop in stroke volume. There is usually a compensatory increase in heart rate to preserve cardiac output and also a compensatory increase in vascular resistance. This vasoconstriction, mediated by endogenous catecholamine release, increases the diastolic pressure without having the same effect on the systolic pressure thus there is a narrowed pulse pressure. Compensatory fluid shifts occur from the extravascular space into the vascular compartment, resulting in intracellular dehydration and a sensation of thirst.