In: Nursing
A 29-year-old female develops sepsis and, as a consequence, she experiences profound vasodilation. a) What effect does vasodilation have on the afterload? Explain why. b) What effect does vasodilation have on blood pressure? Explain why. How will her body try to bring her blood pressure back to homeostasis?
a)Afterload
- The tension or stress developed in the wall of the LV during ejection. The 'load' against which the heart MUST contract to eject blood.
- Pathology of afterload:
Increasing left ventricular afterload include elevated BP & aortic valve disease
Vasodilators (alpha blockers, ACEi, ARBS, BBs, CCBs, nitrodilators, ganglionic blockers, PDE III inhibitors) reduces afterload as they reduce arterial pressure by decreasing systemic vascular resistance.
b) A patient taking a vasodilator relaxes smooth muscles in veins thus causes decrease in blood pressure
- Postural hypotension occurs when moving from a supine or seated position to an upright position. It is caused by relaxation of smooth muscle in veins, which allows blood to pool in veins and decreases venous return of blood to the heart. Patients taking such drugs should avoid abrupt transitions to prevent falls. Prolonged use of vasodilators can lead to expansion of blood volume and fluid overload. Tachycardia can occur when the blood pressure drops as a result of the baroreceptor reflex.
Homeostasis: The regulation of a relatively constant environment within the body
Examples of homeostasis
Control of body temperature, blood sugar level, hormone level and water balance
- The body maintain homeostasis by implementing feed back systems i.e positive and negative system.