The endocrine system is a communicating system that controls functions inside the body. This system, along with other systems, maintains the body’s homeostasis. Endocrine glands secrete messenger hormones; when the hormone arrives, the cell, tissue, or organ receives the message and an action or cellular process takes place. Endocrine disorders are caused by an internal communication problem. If a gland is not functioning normally, it may produce more hormone (hypersecretion) than is needed, or it may not produce enough hormone (hyposecretion). A gland may be functioning correctly, but the receiving organ may not be responding.
In order to survive, the brain needs glucose and oxygen. Insulin is necessary for glucose to enter the cells for metabolism. Without enough insulin, the cells do not get fed. The pancreas produces glucagon and insulin. There are also the islets of Langerhans. Alpha cells produce glucagon and beta cells produce insulin. When a person eats, blood glucose levels rise, the pancreas secretes insulin into the blood, glucose enters the body’s cells and is used for energy. Glucose is also stored as glycogen in the liver and skeletal muscles for later use. Blood glucose levels return to normal, and insulin stops being produced. If a person is hungry but does not eat, a message is sent to the pancreas to secrete glucagon. Glucagon stimulates the liver and skeletal muscles to release glycogen, converting glycogen back to glucose for use as cellular fuel.
Diabetes mellitus is a disorder of glucose metabolism in which the body has an impaired ability to get glucose into the cells to be used for energy. A patient with diabetes has either impaired insulin production or not enough functional receptors on the surface of the cells for insulin to bind to. If glucose cannot get into the cell, the cell goes unfed and levels of glucose in the blood remain high and continue to rise. Without treatment, blood glucose levels can become too high, which can result in coma and death. People who are unable to manage their blood glucose levels often experience severe complications, including blindness, cardiovascular disease, and kidney failure. There are three types of diabetes: type 1, type 2, and pregnancy-induced gestational diabetes. Treatments include injectable hormones that lower the patient’s blood glucose level. Low blood glucose levels (hypoglycemia) can be life-threatening. Some levels to be aware of are the following: if 50 or lower, hypoglycemic crisis; if 50–80, hypoglycemia; if 80–120, normal; if 120–400, hyperglycemia; if 400 or above, DKA, HHNS, or symptomatic hyperglycemia.
With hyperglycemia, the onset is gradual (hours to days). The skin is warm and dry, infection is common, thirst is intense, hunger is present and increasing, and vomiting or abdominal pain is common. Breathing with DKA includes rapid, deep Kussmaul respirations. The odor of the breath with DKA may be a sweet, fruity odor. Blood pressure is typically normal to low, while the pulse is rapid, weak, and thready. Consciousness generally includes restlessness, possibly progressing to coma; abnormal or slurred speech; and an unsteady gait. The response is gradual, occurring over 6–12 hours.
With hypoglycemia, the onset is rapid (within minutes). The skin is typically pale, cool, and moist. Infection is uncommon, thirst is absent, and hunger is also absent. Vomiting and abdominal pain are uncommon. Breathing is normal but may become shallow or ineffective if hypoglycemia is severe and mental status is depressed. The odor of the breath is normal. Blood pressure is normal to low, and the pulse is rapid and weak. Consciousness typically includes irritability, confusion, seizures, or coma, along with an unsteady gait. Treatment is glucose if the person is conscious and not gagging. Hypoglycemia can develop if a person with diabetes takes their medication but fails to eat enough food or takes too much medication.
Diabetes Mellitus Type 1 is an autoimmune disorder in which the individual’s immune system produces antibodies against the pancreatic beta cells. Essentially, this disease is about the missing pancreatic hormone insulin. Without insulin, glucose cannot enter the cell. Onset usually occurs from early childhood through the fourth decade of life. Signs include polyuria, which is a large volume of urine in a given period as a result of glucose wasting in the urine. There is also polydipsia, defined as excessive thirst that persists for long periods despite reasonable fluid intake, often the result of excessive urination. There is also polyphagia, or excessive eating, as the inability to use glucose properly can cause hunger, weight loss, and fatigue. Patients must obtain insulin from an external source and cannot survive without it. People with type 1 diabetes need to check their blood glucose levels up to six times per day or more using a lancet and a glucometer. With advances in technology, it is now possible for someone with type 1 diabetes to have an implanted insulin pump. Some of these devices continuously measure the body’s glucose levels and provide an adjustable infusion of insulin based on carbohydrate intake at mealtimes. Unfortunately, they can malfunction, and hyperglycemic or hypoglycemic emergencies can develop.
The kidneys filter the blood and manage all substances present in the blood. When glucose levels are above normal, the kidney’s filtration system becomes overwhelmed and glucose spills into the urine. Increased amounts of glucose in the urine cause more water to be pulled out of the bloodstream, resulting in polyuria. This can lead to dehydration and increased thirst, which can result in severe electrolyte abnormalities. When the body’s cells do not receive the glucose they require for energy, the body resorts to burning fat for energy. As ketone levels increase in the blood, ketones begin to spill into the urine. This results in faster and deeper breathing due to an imbalance in the body. Kussmaul respirations are the body’s attempt to reduce acid levels by releasing more carbon dioxide. If fat metabolism and ketone production continue, a life-threatening illness called diabetic ketoacidosis (DKA) can develop in patients with diabetes. This presents as a generalized illness with abdominal pain, body aches, nausea, vomiting, and altered mental status or unconsciousness if severe.
Diabetes Mellitus Type 2 is caused by resistance to the effects of insulin at the cellular level. In type 1 diabetes, no insulin is produced; in type 2 diabetes, there are fewer insulin receptors. Obesity predisposes patients to type 2 diabetes. At first, the pancreas produces more insulin to compensate for increased blood glucose levels and cellular dysfunction. Over time, this response becomes inefficient in a process called insulin resistance. In some cases, this can be improved with exercise and dietary modification. Oral medications may be started to better control blood glucose levels. Injectable medications and insulin are also used for type 2 diabetes.
Symptomatic hyperglycemia leads to dehydration due to the discharge of fluids from all body systems and eventually through the kidneys, leading to a more ominous situation of fluid imbalance known as hyperosmolar hyperglycemic nonketotic syndrome (HHNS). This can present similarly to DKA in type 1 diabetes. Key signs include hyperglycemia, altered mental status, drowsiness, lethargy, dehydration, dark urine, visual or sensory deficits, partial paralysis or muscle weakness, and seizures.
The blood is composed of several components, including erythrocytes, leukocytes, platelets, and plasma. Erythrocytes (red blood cells) make up 43–47% of total blood volume. Red blood cells contain an important protein, hemoglobin, which carries 97% of oxygen. Leukocytes (white blood cells) make up about 0.1–0.2% of total blood volume and are part of the body’s defense system. They collect dead cells and provide for their proper disposal. Platelets make up 4–7% of total blood volume and function in clotting. Plasma is the transport medium for all blood components, as well as proteins and minerals.
There are several hematologic emergencies that everyone should be aware of. The first is sickle cell disease, which involves abnormally shaped cells that provide protection in areas where malaria is common. It leads to dysfunction in oxygen binding and unintentional clot formation called a vaso-occlusive crisis. Patients can experience hypoxia, or a lack of oxygen in the body’s cells and tissues. Complications include anemia, gallstones, jaundice, splenic dysfunction, vascular occlusion with ischemia (acute chest syndrome characterized by hypoxia, dyspnea, chest discomfort, and fever), stroke, bone necrosis, pain crises, acute and chronic organ dysfunction or failure, retinal hemorrhages, and an increased risk of infection.
Hemophilia involves acute bleeding from any source and may be life-threatening due to missing clotting factors. Other risks include joint problems, bleeding in the brain, and thrombosis due to treatment. Thrombophilia is a disorder affecting the body’s ability to maintain the viscosity and smooth flow of blood through the venous and arterial systems. Increased concentrations of certain blood elements can lead to clogging or blockage. Deep vein thrombosis is a high risk for patients who have had joint replacement surgery. Be suspicious of this condition in patients with a recent history of joint replacement who complain of leg swelling. If deep vein thrombosis develops, anticoagulation therapy may be administered. Patients prescribed anticoagulation medications are at increased risk for bleeding complications, and even minor trauma may cause hemorrhage. Anemia is a condition characterized by a low number of red blood cells. Tissues may become hypoxic because the blood is unable to deliver adequate amounts of oxygen.
Leave a Reply