GI Study Guide: Intestinal Obstruction: defined as inability of intestinal contents to progress through bowel in a normal manner. Sites of blockage may be located in small intestine or colon. Pathophysiology: Blockage of intestine (regardless of cause) leads to intestinal distention by gas and air, pooling of gastric and biliary secretions, and loss of fluids, electrolytes and proteins. Impaired blood supply leads to increased peristalsis initially ischemia and acidosis bacterial invasion and possibly subsequent necrosis and peritonitis. Complications include fluid and electrolyte imbalances, gangrene of bowel, strangulation of a bowel segment and perforation. S/Sx: colicky pain, distension; Borborygmus bowel sounds changing to hypo/absent sounds. N/V, diarrhea, restlessness, electrolyte imbalances, hypovolemia and shock. ☞Two Classification Types of Obstruction: Mechanical & Functional 1. Mechanical most common caused by any condition that hinders patency of bowel lumen e.g. tumors, adhesions. a. volulus – referring to twisting of the bowel and results in large bowel obstruction (common in elderly). b. Intussusception is intrusion of part of the intestine into another part that lies distal to it. Most common in infants. 2. Functional or paralytic (adynamic) is caused by neurogenic or muscular impairment that hinders peristalsis (post surgery, prolonged bedrest). Peritonitis: Peritoneum is semipermeable membrane and as such an attempt to maintain homeostasis fluid shifts may occur with third-spacing into peritoneal cavity; dehydration, decreased urinary output, hypovolemia, electrolyte imbalance and even shock may occur. If secretions or chemical irritants leading into peritoneum are sterile, irritation is primarily chemical; if they are infected, an intense inflammatory response is generated. S/Sx: abdominal pain that is intense often localized, at the site of involvement then diffuse; chills and fever, anorexia, nausea, vomiting, guarding and rigidity of abdomen; abdominal distention, diminished or absent bowel sounds, sweating, tachycardia, oliguria, restlessness, elevated WBC, pallor, shallow inspiratory effort (relating to abdominal pain) tachypnea. Pancreatitis is Heptobilary Problem: defined as inflammation of pancreas. When pancreas is injured and or function is disrupted pancreatic enzymes lead into pancreatic tissue and initiate autolysis. Pancreatitis Causes Mnemonic: I GET SMASHED: Idiopathic Gallstones Ethanol Trauma Steroids Mumps Autoimmune Scorpion sting Hyperlipidemia/hypercalcemia ERCP Drugs S/Sx: Sudden onset of severe epigastric and abdominal tenderness and pain that radiates to back; maybe relieved by sitting up and leaning forward flexing leg or by walking; may be initiated by fatty meal or excessive alcohol intake. Tx: Pain management; pancreatic enzyme replacement, reduce gastric secretions (NGT to low suction), Maintain NPO status 3 to 7 days; nutritional support. Cholecystitis inflammation of cystic duct caused by lodging of a gallstone in duct. S/Sx: pain that suddenly or gradually develops (classically in back or right shoulder) fever, N/V jaundice, clay colored stools, intolerance to fat-containing foods, epigastric pain, heartburn. Liver Dysfunction Hepatitis: Inflammation of the Liver Hepatitis Type Populations at risk for Acquiring A Drinking contaminated milk or water and consumption of shellfish from contaminated water. Children in day care centers and institutionalized adults are at greater risk for contracting. B Contact with blood or serum and oral or sexual contact. C Iv drug abusers, persons receiving blood transfusions, health care workers, persons on hemodialysis those with high risk sexual behavior, and organ transplant recipients. D: IV drug users and those receiving clotting factor concentrates. E Pregnant women in developing countries Hepatic Encephalopathy –If the liver is not functioning ammonia is not broken down and it accumulates in bloodstream crosses the blood brain barrier and goes to brain tissue. The damage to the brain tissue caused by ammonia in brain is known as hepatic encephalopathy. This can be precipitated by any major event hemodynamic insult to the body such as bleeding, shock, toxins, hypovolemia anything that can cause increased metabolic demands of liver. Esophageal Varices – increased pressure in portal veins that occur from prolonged elevation of pressure. Most commonly located in stomach and lower esophagus but may also be found in rectum. Mortality is 30-60% most die within a year. Usually associate with portal hypertension increased pressure in portal vein caused by obstruction or congestion. Associated with alcohol abuse and cirrhosis. S/Sx: vomiting of dark colored blood . Endocrine Study Guide: Adrenal Gland Dysfunction: Overview Pathophysiology- Adrenal medulla secretes catecholamines(epinephrine and norepinephrine and dopamine. Adrenal cortex secretes mineralocorticoids (aldosterone), glucocorticoids (cortisol) and androgens and estrogens (sex hormones). Adrenal Cortex hyperfunction results in overproduction of a. Cortisol results in Cushings disease b. Aldosterone results in Conn disease. S/Sx Cushings; moon face, water retention edema, truncal obesity, buffalo hump (dorsocervical fat baad at back of neck and upper back, purple striae. Pituitary: Anterior & Posterior Anterior pituitary secretes growth hormones dysfunction results in acromegaly, giantism, and dwarfism Posterior pituitary secretes ADH (antidiuretic hormone). Hypofunction – results in decreases in ADH and Diabetes Insipidus (excessive water loss via kidneys). Causes; head trauma, brain tumor, removal/irradiation of pituitary gland Hyperfunction - results in increases in ADH and SIADH – excessive water retention. Thyroid: Secretes hormones; Thyroxine(T4) responsible for cellular metabolism; Triiodothyronine (T3) responsible for regulating cellular metabolism. T3 and T4 are referred to collectively as thyroid hormone TH and secretes Thryocalcitonin (calcitonin) role is calcium regulation. Iodine is necessary for thyroid gland to synthesize and secrete hormones. Calcitonin acts on kidneys and bones to decrease serum calcium levels. Causes of Thyroid dysfunction: autoimmune responses, neoplasms, excessive intake of thyroid medications and excess secretion of thyroid secreting hormone from anterior pituitary gland. Hyperthyroidism is an excess of thyroid hormone (TH) which places the body in a hypermetabolic state manifested by increases in appetite, body temperature, and oxygen consumption. hyper function of the thyroid gland leads to excess of TH (thyroid hormone). Thyroid hormone production depends on adequate secretion of TSH from anterior pituitary; hypothalamus regulates TSH secretion by negative feedback. Thryoid hyperfunction S/Sx: classic symptoms are weight loss, nervousness, exophthalmos increased appetite palpitations heat intolerance. Disorders include: Graves ’disease, toxic goiter, and Thyroid storm. Graves ’disease is then most common form of hyperthyroidism. Seen most frequently in women under 40. Exophthalmos relating to Graves ’disease results from accumulation of fat and by-products in the retro-orbital tissues – this is not reversible. The client needs to be provided with eye care instruction to prevent drying and injury to eyes. Toxic Goiter: exists when small independently functioning nodules either benign or malignant in thyroid gland are present and secrete TH seen in women over 60 with long term goiter. Thyroid storm: is a life threatening condition Hypothyroid: Myxedema coma is considered a life threatening emergency relating to hypothyroidism. Myxedema describes a generalized hypo-metabolic state occurring with untreated hypothyroidism accumulation of proteins in interstitial spaces results in an increase in interstitial fluids causing mucinous edema myxedema, a non-pitting edema. Myxedema coma hypothyroid crisis results from extreme or prolonged though rare it is a life threatening condition. S/Sx: hypothermia, cardiovascular collapse, coma, hyponatremia, hypoglycemia, lactic acidosis. Parathyroid Function: Major function is to maintain normal calcium levels by secreting parathyroid (PTH) which increase bone resorption of calcium. Hypercalcemia: Serum calcium (8.5 to 10.2mg/dL, according to Lewis 2014, pg 1501). There is general mnemonic for remembering the effects of hypercalcemia: "Stones, Bones, Groans, Thrones and Psychiatric Overtones" Stones (kidney or biliary) (see calculus) Bones (bone pain) Groans (abdominal pain, nausea and vomiting) Thrones (polyuria) resulting in dehydration due to nephrogenic diabetes insipidus from nephrocalcinosis Psychiatric overtones (Depression 30–40%, anxiety, cognitive dysfunction, insomnia, coma). Hypocalcemia: Serum calcium <8.5 mg/dL). Caused by inadequate intestinal absorption, deposition of ionized calcium into bone and or soft tissue, blood administration (citrated blood products) or decrease in PTH (parathyroid hormone) and vitamin D, nutritional deficiencies occur with inadequate sources of dairy product or green leafy vegetables. S/Sx: increased neuromuscular excitability, tingling muscle spasm particularly in hands, feet and facial muscles, intestinal cramping, hyperactive bowel sounds, severe cases show convulsions and tetany, prolonged QT and cardiac arrest. Chvostek’s (tetany) & Trousseau’s (hyperreflexia) signs. Pancreas: Beta cells (Islets of Langerhans) produced in head of pancreas. Diabetes mellitus: is defined as a lack of or inadequate secretion of insulin or insulin resistance resulting in hyperglycemia. Type I – results from destruction of pancreatic eta cells, which leads to insulin dependence (no insulin is produced from beta cells of pancreas). Insulin must be received exogenously. Causes: genetic, environmental, or immunological factors that damage beta cells. Type II- results from a decrease in beta cell weight and number or insulin resistance; may be managed with diet and exercise, and/or oral antidiabetic agents.; situations increasing stress on body (surgery, illness, trauma) may create a need for supplemental insulin temporarily because of rise in glucose levels because of adrenal cortex response to stress. Causes: unknown however obesity is most important risk factor.
