Pregnancy Induced Hypertension Sample Essay

Pregnancy Induced Hypertension (PIH) is a condition in which vasospasms occur during pregnancy in both small and large arteries. Signs of hypertension, proteinuria, and edema develop. Despite years of research, the cause of the disorder is still unknown. Originally it was called toxemia because researchers pictured a toxin of some kind being produced by a women in response to foreign protein of the growing fetus, the toxin leading to the topical symptoms. No such toxins have ever been identified.

A condition separate from chronic hypertension, PIH tends to occur most frequently in women of color or with a multiple pregnancy; primiparas are younger than 20 years of age or older than 40 years, women from low socio economic backgrounds, those who have an underlying disease such as heart disease, diabetes with vessel or renal involvement and essential hypertension. Pregnancy Induced Hypertension Sample Essay

PIH is classified as gestational hypertension, mild preeclampsia, severe preeclampsia and eclampsia, depending on how far development advances. Gestational hypertension when develops an elevated blood pressure but has no proteinuria or edema. Perinatal mortality is not increased with simple gestational hypertension, so no drug therapy is necessary; and blood pressure returns to normal after birth. Mild preeclampsia when blood pressure rises to 140/90 mmHg or systolic pressure elevated 15 mmHg above pregnancy level; mild edema in upper extremities or face. Severe preeclampsia when blood pressure has risen to 160 mmHg systolic and 110 mmHg diastolic; proteinuria; pulmonary or cardiac involvement; extensive peripheral edema; hepatic dysfunction; theombocytopenia. Eclampsia is the most severe classification of PIH and seizure or coma Accompanied by s/s of preeclampsia. Any woman who falls into one of the high-risk categories for PIH should be observed carefully for symptoms at prenatal visits. She needs instructions about what symptoms to watch for so she can alert her clinician if additional symptoms occur between visits.\

Anatomy and Physiology:

When most people hear the term cardiovascular system, they immediately think of the heart. We have all felt our own heart “pound” from time to time, and we tend to get a bit nervous when this happens. The crucial importance of the heart has been recognized for a long time. However, the cardiovascular system is much more than just the heart, and from a scientific and medical standpoint, it is important to understand why this system is so vital to life. Pregnancy Induced Hypertension Sample Essay

Most simply stated, the major function of the cardiovascular system is transportation. Using blood as the transport vehicle, the system carries oxygen, nutrients, cell wastes, hormones, and many other substances vital for body homeostasis to and from the cells. The force to move the blood around the body is provided by the beating heart. The cardiovascular system can be compared to a muscular pump equipped with one-way valves and a system of large and small plumbing tubes within which the blood travels.

HEART:The heart is a muscular organ found in all vertebrates that is responsible for pumping blood throughout the blood vessels by repeated, rhythmic contractions.
The heart is enclosed in a double-walled sac called the pericardium. The superficial part of this sac is called the fibrous pericardium. This sac protects the heart, anchors its surrounding structures, and prevents overfilling of the heart with blood. It is located anterior to the vertebral column and posterior to the sternum. The size of the heart is about the size of a fist and has a mass of between 250 grams and 350 grams. The heart is composed of three layers, all of which are rich with blood vessels. The superficial layer, called the visceral layer, the middle layer, called the myocardium, and the third layer which is called the endocardium. The heart has four chambers, two superior atria and two inferior ventricles. The atria are the receiving chambers and the ventricles are the discharging chambers. The pathway of blood through the heart consists of a pulmonary circuit and a systemic circuit. Blood flows through the heart in one direction, from the atrias to the ventricles, and out of the great arteries, or the aorta for example. This is done by four valves which are the tricuspid atrioventicular valve, the mitral atrioventicular valve, the aortic semilunar valve, and the pulmonary semilunar valve.
Systemic circulation is the portion of the cardiovascular system which carries oxygenated blood away from the heart, to the body, and returns deoxygenated blood back to the heart. The term is contrasted with pulmonary circulation.

Pulmonary circulation is the portion of the cardiovascular system which carries oxygen-depleted blood away from the heart, to the lungs, and returns oxygenated blood back to the heart. The term is contrasted with systemic circulation. A separate system known as the bronchial circulation supplies blood to the tissue of the larger airways of the lung. Pregnancy Induced Hypertension Sample Essay

Arteries are blood vessels that carry blood away from the heart. All arteries, with the exception of the pulmonary and umbilical arteries, carry oxygenated blood.

Pulmonary arteries: The pulmonary arteries carry deoxygenated blood that has just returned from the body to the heart towards the lungs, where carbon dioxide is exchanged for oxygen.

Systemic arteries: Systemic arteries can be subdivided into two types – muscular and elastic – according to the relative compositions of elastic and muscle tissue in their tunica media as well as their size and the makeup of the internal and external elastic lamina. The larger arteries (>10mm diameter) are generally elastic and the smaller ones (0.1-10mm) tend to be muscular. Systemic arteries deliver blood to the arterioles, and then to the capillaries, where nutrients and gasses are exchanged.

The Aorta:The aorta is the root systemic artery. It receives blood directly from the left ventricle of the heart via the aortic valve. As the aorta branches, and these arteries branch in turn, they become successively smaller in diameter, down to the arteriole. The arterioles supply capillaries which in turn empty into venules. The very first branches off of the aorta are the coronary arteries, which supply blood to the heart muscle itself. These are followed by the branches off the aortic arch, namely the brachiocephalic artery, the left common carotid and the left subclavian arteries.

Aorta the largest artery in the body, originating from the left ventricle of the heart and extends down to the abdomen, where it branches off into two smaller arteries (the common iliacs). The aorta brings oxygenated blood to all parts of the body in the systemic circulation. Pregnancy Induced Hypertension Sample Essay

The aorta is usually divided into five segments/sections:

• Ascending aorta—the section between the heart and the arch of aorta
• Arch of aorta—the peak part that looks somewhat like an inverted “U”
• Descending aorta—the section from the arch of aorta to the point where it divides into the common iliac arteries
  o    Thoracic aorta—the half of the descending aorta above the diaphragm
  o    Abdominal aorta—the half of the descending aorta below the diaphragm

Arterioles: Arterioles, the smallest of the true arteries, help regulate blood pressure by the variable contraction of the smooth muscle of their walls, and deliver blood to the capillaries.
Veins are blood vessels that carry blood towards the heart. Most veins carry deoxygenated blood from the tissues back to the lungs; exceptions are the pulmonary and umbilical veins, both of which carry oxygenated blood. Veins differ from arteries in structure and function; for example, arteries are more muscular than veins and they carry blood away from the heart.
Veins are classified in a number of ways, including superficial vs. deep, pulmonary vs. systemic, and large vs. small.

Superficial veins: Superficial veins are those whose course is close to the surface of the body, and have no corresponding arteries.

Deep veins: Deep veins are deeper in the body and have corresponding arteries. Pregnancy Induced Hypertension Sample Essay

Pulmonary veins: The pulmonary veins are a set of veins that deliver oxygenated blood from the lungs to the heart.

Systemic veins: Systemic veins drain the tissues of the body and deliver deoxygenated blood to the heart.
Atrium sometimes called auricle, refers to a chamber or space. It may be the atrium of the lateral ventricle in the brain or the blood collection chamber of a heart. It has a thin-walled structure that allows blood to return to the heart. There is at least one atrium in animals with a closed circulatory system.

Right atrium is one of four chambers (two atria and two ventricles) in the human heart. It receives deoxygenated blood from the superior and inferior vena cava and the coronary sinus, and pumps it into the right ventricle through the tricuspid valve. Attached to the right atrium is the right auricular appendix.

Left atrium is one of the four chambers in the human heart. It receives oxygenated blood from the pulmonary veins, and pumps it into the left ventricle, via the atrioventricular valve.
Ventricle is a chamber which collects blood from an atrium (another heart chamber that is smaller than a ventricle) and pumps it out of the heart.
Right ventricle is one of four chambers (two atria and two ventricles) in the human heart. It receives deoxygenated blood from the right atrium via the tricuspid valve, and pumps it into the pulmonary artery via the pulmonary valve and pulmonary trunk.

Left ventricle is one of four chambers (two atria and two ventricles) in the human heart. It receives oxygenated blood from the left atrium via the mitral valve, and pumps it into the aorta via the aortic valve. Pregnancy Induced Hypertension Sample Essay

Pathophysiology of Pregnancy Induced Hypertension (PIH): 

Preeclampsia is a characterized, by vasospasms, changes in the coagulation system, and disturbances in systems related to volume and BP control. Vasospasms results from an increased sensitivity to circulating pressures, such as angiotensin II, and possibly an imbalance between the prostaglandins prostacyclin and thromboxane A1.

Endothelial cell dysfunction, believed to result from decreased placental perfusion, may account for many changes in preeclampsia. Arteriolar vasospasm may cause endothelial damage and contribute to an increased capillary permeability. This increase edema and further decreases intravascular volume, predisposing the woman with preeclampsia to pulmonary edema.

Immunologic factors may play an important role in the development of preeclampsia. The presence of a foreign protein, the placenta, or the fetus maybe perceived by the mother’s immune system as an antigen. This may then trigger an abnormal immunologic response. This theory is supported by the increased incidence of preeclampsia or eclampsia in first-time mothers or to multiparous woman pregnant by a new partner. Preeclampsia maybe an immune complex disease in which the maternal antibody system is overwhelmed from excessive fetal antigens in the maternal circulation. This theory seems compatible with the high incidence ofpreeclampsia among women exposed to a large mass of trophoblastic tissue as seen in twin pregnancies or hydatidiform moles.

Genetic predisposition maybe another immunologic factor. Dekker reported a greater frequency of preeclampsia and eclampsia among daughters and granddaughters of women with a history of eclampsia, which suggests an autosomal recessive gene controlling the maternal immune response. Paternal factors are also examined.Pregnancy Induced Hypertension Sample Essay

Diets in inadequate nutrients, especially protein, calcium, sodium, magnesium, and vitamin E and C, maybe an etiologic factor in preeclampsia. Some practitioners prescribed high-protein diets (90 mg supplemental protein) without caloric restriction and moderate sodium intake in the prevention and treatment of this disorder. However, data are limited regarding the association between diet and preeclampsia.

Preeclampsia progress along a continuum from mild disease to severe preeclampsia, HELLP syndrome, or eclampsia. The pathophysiology of preeclampsia reflects alteration in the normal adaptations of pregnancy. Normal physiologic adaptations to pregnancy include increase blood plasma volume, vasodilation, and decreased systemic vascular resistance, elevated cardiac output, and decreased colloid osmotic pressure. Pathologic changes in the endothelial cells of the glomeruli are uniquely characteristic of preeclampsia, particularly in nulliparous women. The main pathogenic factor is not an increase in BP but poor perfusion as a result vasospasm. Arteriolar vasospasm diminishes the diameter of blood vessels, which impedes blood flow to all organs and raises BP. Function in organs such as the placenta, kidneys, liver and brain is deceased by as much as 40% to 60%.