Theory Nephrology PDF

NEPHROLOGY Chronic Kidney Disease (CKD) Discussion Chronic kidney disease (CKD) is defined as abnormalities of kidney structure or function that persist for more than three months and have health implications. CKD includes all people with markers of kidney damage, and individuals...

NEPHROLOGY Chronic Kidney Disease (CKD) Discussion Chronic kidney disease (CKD) is defined as abnormalities of kidney structure or function that persist for more than three months and have health implications. CKD includes all people with markers of kidney damage, and individuals with a glomerular filtration rate (GFR) of less than 60 mL/min/1.73 m2 on at least two occasions separated by at least 90 days, with or without markers of kidney damage. CKD is characterized by a progressive and irreversible loss of kidney function. As nephrons lose functionality, the glomerular filtration rate (GFR) declines, hindering the kidneys' ability to filter waste products from the blood, a condition known as azotemia. A normal GFR is 125 mL/min, reflected by urine creatinine clearance. The two primary causes of renal failure are diabetes mellitus and hypertension. Effects and Manifestations of CKD CKD impacts various body systems, leading to diverse manifestations: o Cardiovascular: Elevated blood pressure, heart rate, and fluid retention can lead to peripheral and pulmonary edema. Dysrhythmias, abnormal heart sounds, and pericardial friction rub may also occur. o Respiratory: Increased respiratory rate, Kussmaul respirations (deep, rapid breathing), crackles (abnormal lung sounds), decreased oxygen saturation, and shortness of breath. o Renal: Reduced urinary output, azotemia, proteinuria (protein in the urine), hematuria (blood in the urine), and hyperuricemia (high uric acid levels in the blood). o Integumentary: Bruising, itching (pruritus), dry skin, changes in skin color (ashen gray to yellowish), and dry, brittle hair and nails. o Gastrointestinal: Anorexia, nausea, vomiting, halitosis (bad breath), metallic taste in the mouth, and gastrointestinal bleeding. o Neurological: Peripheral neuropathy, restless legs syndrome, altered level of consciousness, lethargy, confusion, encephalopathy (brain dysfunction), and changes in motor function. o Musculoskeletal: Renal osteodystrophy (bone disease), decreased calcium levels, impaired vitamin D metabolism, hyperparathyroidism (overactive parathyroid gland), and pathological fractures (bone fractures caused by underlying disease). o Immune: Increased susceptibility to both local and systemic infections. o Hematological: Anemia, manifesting as weakness, fatigue, pallor, lethargy, and bleeding. End-Stage Renal Disease (ESRD): When GFR falls below 15 mL/min/1.73m2, the kidneys can no longer effectively filter, secrete, reabsorb, and excrete. This stage, known as ESRD, worsens existing manifestations and necessitates renal replacement therapy for survival. Common Lab Tests and Findings in CKD  Creatinine: A breakdown product of creatinine phosphate in muscle, creatinine is filtered by the kidney and used to estimate kidney function. Higher creatinine levels indicate lower filtration (GFR). Blood Urea Nitrogen (BUN): Urea is formed by the liver during protein breakdown. Filtered by the kidney, BUN is also used to assess kidney function. Elevated BUN levels reflect reduced filtration. However, certain medications like steroids and some antibiotics can increase BUN levels without indicating kidney dysfunction. Oliguria and Anuria: Oliguria is defined as urine output less than 400-500 mL in 24 hours, while anuria is urine output less than 100 mL in 24 hours. Key Concepts Not Covered in the Sources It is important to note that the provided sources do not cover certain key aspects of CKD, such as: Staging of CKD: CKD is classified into five stages based on the level of kidney function (GFR). Specific treatment options for different stages of CKD: Treatment approaches vary depending on the stage and underlying causes of CKD. Complications of CKD: CKD can lead to various complications, including cardiovascular disease, bone disease, anemia, and electrolyte imbalances. Long-term management of CKD: Managing CKD involves a multidisciplinary approach, including lifestyle modifications, medications, and, in advanced stages, renal replacement therapy. Here is a discussion of Renal Replacement Therapies based on the provided sources: Renal Replacement Therapies Renal replacement therapies are used when a patient's kidneys are no longer able to function properly. When the glomerular filtration rate (GFR) is less than 15 ml/min, fluids, waste products, and electrolytes build up in the blood, and very little urine is produced. When this happens, renal replacement therapy is needed to keep the patient alive. There are two main types of renal replacement therapy: o Peritoneal Dialysis: In this type of dialysis, the peritoneum, the lining of the abdominal cavity, is used as a membrane to filter fluids and waste from the blood. Dialysate is put into the peritoneum and left there for a certain amount of time before it is drained. During this "dwell time," fluids move from the blood into the dialysate through a process called osmosis. Waste products, such as urea, creatinine, potassium, and sodium, move from the blood into the dialysate by diffusion. Osmosis is the movement of water from an area of low solute concentration (the blood) to an area of high solute concentration (the dialysate). Diffusion is the movement of solutes from an area of high concentration to an area of low concentration. o Hemodialysis: Hemodialysis uses a machine to clean the blood and then returns the filtered blood to the patient's body. Each hemodialysis treatment removes about two liters of fluid from the body. In order for hemodialysis to work, the patient needs to have a way for the blood to be taken out and returned to the body. This is called vascular access.  Components of a Hemodialysis System:  Blood is removed through a needle placed in a fistula or a catheter lumen.  A blood pump moves the blood to the dialyzer.  Heparin is infused to prevent clotting.  Dialysate is pumped into the dialyzer and flows in the opposite direction of the blood.  The dialyzed blood is returned to the patient through a second needle or catheter lumen.  The old dialysate and ultrafiltrate are drained and thrown away.  Vascular Access for Hemodialysis:  Arteriovenous fistula (AVF): This is created by surgically joining an artery and a vein. The high-pressure blood from the artery flows into the vein, which makes the vein thicker and larger in diameter. It takes 2–6 months for an AVF to mature before it can be used for hemodialysis. As it matures, the vein will become more visible on the skin. Hand and arm exercises, such as squeezing a rubber ball, can help the AVF mature faster by increasing blood flow and strengthening the muscles around it. Hemodialysis requires blood flow rates of 300–600 ml/min, and the thicker vein wall in the AVF can tolerate these higher rates.  Example of a vascular access sign:  "Client has (write name of access) ____________ (fistula, graft) in __________________________ (write location of body) for hemodialysis. No blood pressure on this extremity. No venipuncture, capillary puncture, or arteriopuncture in this extremity. No peripherally inserted central catheter (PICC) in this extremity. No arterial line in this extremity. No identification band on this extremity. Nothing tight on this extremity. Do not bend this extremity."  Assessment of an Arteriovenous Fistula and/or Graft:  Inspect: Inspect the area around the extremity for continuity of skin color, signs and symptoms of infection and/or inflammation, edema, rash or unhealed scars, and broken skin or bleeding. Call the physician if bleeding does not stop.  Palpate: Feel for a thrill (vibration) over and around the access, pulses above and below the access, capillary refill  in fingernails or toenails, and continuity of skin temperature.  Auscultate: Listen for a bruit (a whooshing sound) with a stethoscope. Call the dialysis unit immediately if there is no bruit. Care of a Patient Receiving Hemodialysis Frequency of treatment: Patients receiving hemodialysis are usually treated three times a week for two hours each time or six times a week for two hours each time. Some patients can have hemodialysis at home during the night (nocturnal dialysis) or during the day (independent dialysis). Assessment and care after hemodialysis: o Dry Weight: Dry weight is the lowest weight a patient can tolerate after hemodialysis without experiencing symptoms of hypovolemia (too little fluid in the blood) or hypervolemia (too much fluid in the blood). Dry weight is achieved by gradually changing the patient's post-dialysis weight. One of the goals of hemodialysis is to help the patient maintain euvolemia, which is a normal amount of fluid in the body. One liter of fluid equals 1 kg of weight. o Volume Status: A large amount of fluid, usually more than two liters, is removed from the blood during hemodialysis. Intradialytic hypotension, or low blood pressure during dialysis, can happen if the body doesn't replace this fluid quickly enough. After fluid is removed from the blood, fluid in the tissues and cells of the body should move into the blood vessels by osmosis. If this doesn't happen, hypotension can occur. In the long term, the low blood flow (hypoperfusion) and hypotension caused by low fluid volume can lead to myocardial infarction (heart attack), heart failure, stroke, cognitive deficits, and bowel ischemia. o Blood Pressure: Blood pressure can be affected by the amount of fluid in the blood vessels, but it can also be affected by other things, like coronary artery disease. Therefore, blood pressure is not a perfect measure of fluid volume.  Assessing for hypervolemia (fluid volume excess) and hypovolemia (fluid volume deficit):  Signs of Fluid Volume Excess Before Hemodialysis: Increased blood pressure, bounding pulse, jugular vein distention (JVD), increased respiratory rate, shortness of breath, crackles in the lungs, peripheral/pitting edema (swelling in the legs, ankles, feet, or sacrum), generalized edema (anasarca), increased weight, headache, fatigue, and changes in activity level.  Signs of Fluid Volume Deficit After Hemodialysis: Decreased blood pressure (especially postural hypotension, which is a drop in blood pressure when standing up), increased heart rate (with a weak pulse), increased respiratory rate, fever, dry mucous membranes, tenting of the skin, flat neck veins when lying down, weight loss, neurological changes, and decreased urine output (although this may not be a reliable indicator in patients with kidney disease). o Acid-Base and Electrolytes: Patients with end-stage renal disease (ESRD) may have a number of acid-base and electrolyte imbalances.  Pre-Dialysis Imbalances: Metabolic acidosis (low blood pH and low bicarbonate), high potassium, low sodium (although this can vary depending on fluid volume), low calcium, high phosphate, high magnesium, high glucose, and uremia (a buildup of waste products in the blood, which can cause nausea, vomiting, fluid overload, hyperkalemia, and severe acidosis).  Post-Dialysis Imbalances: Metabolic alkalosis (high blood pH and high bicarbonate) can occur if the dialysate is high in bicarbonate. Patients may also experience shifts in electrolyte levels after dialysis; these shifts are usually the opposite of the pre-dialysis levels but can depend on the type of dialysate used.  Nursing assessments of electrolyte imbalances:  Hyponatremia: Irritability, apprehension, confusion, seizures, headache, nausea, vomiting, weight loss, dehydration, lethargy, intense thirst.  Hypernatremia: Restlessness, agitation, twitching, seizures, coma.  Hypokalemia: Fatigue, muscle weakness, bradycardia, leg cramps, weak, soft, flabby muscles, polyuria (may not be present due to underlying kidney disease), hyperglycemia, arrhythmias, and ECG changes.  Hyperkalemia: Weakness, fatigue, paresthesia, depression of deep tendon reflexes, palpitations, and cardiac arrhythmias.  Hypocalcemia: Neuromuscular symptoms, such as tetany, paresthesia of the hands and feet, positive Chvostek’s and Trousseau’s signs, seizures, easy fatigability, depression, anxiety, and confusion, as well as cardiac symptoms like hypotension and ECG changes, and respiratory symptoms like laryngeal spasm, bronchospasm, and stridor.  Hypercalcemia: Lethargy, muscle weakness, depressed deep tendon reflexes, decreased memory, confusion, personality changes, psychosis, stupor, coma, bone pain, fractures, anorexia, nausea, vomiting, increased thirst, and constipation.  Hypophosphatemia: Muscle weakness, tremors, paresthesia, bone pain, diminished reflexes, seizures, delirium, hallucinations, tissue hypoxia, bleeding, possible infection, weak pulse, hyperventilation, respiratory weakness, anorexia, and dysphagia.  Hyperphosphatemia: Tetany, hyperreflexia, muscle weakness, flaccid paralysis, painful joints, tachycardia, nausea, vomiting, abdominal cramps, and dry, itchy skin. o Malnutrition: Malnutrition is a common problem for dialysis patients, with studies showing it affects anywhere from 18% to 75% of patients. Malnutrition occurs when a patient doesn't eat enough, loses nutrients during dialysis, or has other health problems that speed up their metabolism (like an infection).  Malnutrition can lead to muscle wasting. Albumin levels and dry weight can be used to assess for malnutrition. o Mineral and Bone Disorder (MBD): Patients with chronic kidney disease (CKD) and ESRD have problems regulating Vitamin D. This can lead to low levels of Vitamin D and calcium, and high levels of phosphorus and parathyroid hormone (PTH). MBD can lead to cardiovascular disease and bone fractures. o Anemia: The kidneys typically produce erythropoietin, a hormone that regulates red blood cell (RBC) production. Anemia in patients with kidney disease is caused by a decrease in RBC production by the bone marrow, which results in low hemoglobin levels. When RBC levels are low, the body's tissues and organs don't get enough oxygen.  Manifestations of Anemia: Weakness, fatigue, headaches, problems concentrating, pale skin, dizziness, difficulty breathing or shortness of breath, chest pain, tachycardia, and irregular heartbeat. o Inflammation/Infection: Patients with kidney disease often have diabetes, which puts them at higher risk of developing infections. These patients may also have impaired wound healing and chronic wounds. When tissues don't get enough blood, it can lead to tissue death (necrosis) and ultimately amputation of the affected limb if the infection isn't treated. o Medications:  Medications to Control Blood Pressure:  ACE Inhibitors: These medications block the conversion of angiotensin I to angiotensin II, which lowers blood pressure by widening blood vessels. ACE inhibitors also stop the adrenal glands from releasing aldosterone, which can also help lower blood pressure. ACE inhibitors usually end in "-pril."  Angiotensin Receptor Blockers (ARBs): ARBs lower blood pressure by blocking the action of angiotensin II. They work by preventing angiotensin II from binding to its receptors on the muscles that surround blood vessels, which causes the blood vessels to relax and widen (dilate). ARBs typically end in "- sartan."  Calcium Channel Blockers: These medications lower blood pressure by preventing calcium from entering the cells of the heart and blood vessel walls. Calcium channel blockers also relax and widen blood vessels by affecting the muscle cells in the arterial walls. Some calcium channel blockers can also slow down the heart rate, which can further reduce blood pressure, relieve chest pain (angina), and control an irregular heartbeat.  Other Medications:  Phosphate Binders: Phosphate binders are used to decrease the amount of phosphate that is absorbed from food. Phosphate binders that contain calcium are often the first choice of treatment for dialysis patients, although research is being done on other types of phosphate binders, such as magnesium-based binders.   Calcium Carbonate: Calcium carbonate pills should be given with meals unless the nephrologist orders otherwise.  Iron Pills: Iron pills, such as ferrous gluconate, should be given between meals. o Diet: When the kidneys aren't working properly, patients need to be careful about the types and amounts of food they eat. Working with a dietitian, patients can create individualized meal plans that minimize or control the intake of certain nutrients:  Potassium: Foods high in potassium include potatoes, squash, bananas, oranges, tomatoes, and dried peas and beans.  Sodium: Processed foods, like deli meats, canned foods, convenience foods, fast foods, salty snacks, and salty seasonings are high in sodium.  Phosphorus: Milk, cheese, and other dairy products, as well as protein foods like meat, fish, and poultry, are high in phosphorus.  Protein: Patients with kidney disease need to consume the right amount of protein. Too much protein can lead to a buildup of urea, while too little protein can lead to malnutrition and problems with tissue repair. Foods high in protein include meat, fish, poultry, eggs, tofu, and milk. o Fluid Restrictions: Fluid intake for dialysis patients is usually calculated by adding 400–600 ml to the patient's urine output. The extra 400–600 ml accounts for the fluid that is lost through the skin and lungs. Most patients on dialysis do not produce urine. For these patients, a safe daily fluid intake is between 500 and 1000 ml, which should limit weight gain to 0.5–1.0 kg. Nursing Assessments in Renal Disease The sources discuss nursing assessments related to chronic kidney disease (CKD) and end-stage renal disease (ESRD), including assessments related to the cardiovascular, respiratory, renal, integumentary, gastrointestinal, neurological, musculoskeletal, immune, and hematological systems. Cardiovascular System Before Hemodialysis: Monitor for signs of fluid volume excess such as increased blood pressure, bounding pulse, jugular vein distention, increased respiratory rate, shortness of breath, crackles in the lungs, peripheral/pitting edema, generalized edema, increased weight, headache, fatigue, and changes in activity. General: Monitor lab values (CBC, electrolytes), vital signs frequently, auscultate lungs for edema, assess for jugular vein distention, assess peripheral vascular changes, take pulse and BP both upright and supine, listen to heart sounds for abnormalities, weigh daily, inspect skin for fluid retention, and ask the patient if they feel any irregular heartbeats. Respiratory System  General: Inspect thorax for symmetrical movement, inspect skin for pallor, auscultate lung fields, note changes in rate, rhythm, effort of breathing and presence of fluid, and monitor oxygen saturation and arterial blood gases. Renal System General: Maintain strict intake and output records, assess for costovertebral tenderness, abdominal distention and tenderness, test urine for protein and red blood cell casts, and monitor renal function tests (BUN, creatinine). Other Systems Integumentary System: Inspect skin, hair, and nails, monitor liver function tests, uric acid levels, and platelets. Abdomen: Weigh daily, monitor nutrition status closely, assess emesis, monitor bowel movements for frank or occult blood, palpate abdomen for tenderness, auscultate bowel sounds and listen over abdominal aorta for bruits, and inspect the abdomen for distention. Neurological System: Assess the 3 spheres (person, place, and time), assess for changes in level of consciousness, assess memory, perform a cranial nerve assessment, perform a motor assessment, and perform a muscle tone assessment. Musculoskeletal System: Assess for musculoskeletal pain and limitations, and monitor electrolyte levels (especially phosphate and calcium). Immune System: Monitor wounds for signs of infection (redness, swelling, pain, heat, drainage), assess for fever, chills, malaise, and leukocytosis, and monitor WBCs. Hematological System: Monitor CBC (hemoglobin, platelets, albumin, hematocrit). Assessments Before and After Hemodialysis Fluid Status: Monitor for fluid volume excess before hemodialysis and fluid volume deficit after hemodialysis. Signs and symptoms of each are detailed in the source. Acid-Base and Electrolytes: Be aware of potential acid-base and electrolyte imbalances pre and post-dialysis and watch for electrolyte shifts. Report abnormal values. Other Assessments: Monitor dry weight, blood pressure, uremia, anemia, malnutrition, mineral and bone disorder, inflammation, infection, medications, and diet. Electrolyte Imbalances The sources provide detailed information on the nursing assessments for electrolyte imbalances, including: Hyponatremia: Irritability, apprehension, confusion, seizures, headache, nausea and vomiting, weight loss, dehydration, lethargy. Hypernatremia: Intense thirst, restlessness, agitation, twitching, seizures, coma. Hypokalemia: Fatigue, muscle weakness, bradycardia, leg cramps, weak, soft, flabby muscles, polyuria, hyperglycemia, arrhythmias.  Hyperkalemia: Cardiac and neuromuscular symptoms, weakness, fatigue, paresthesia, depression of deep tendon reflexes, palpitations, cardiac arrhythmias. Hypocalcemia: Neuromuscular: tetany, paresthesia of hands and feet, + Chvostek’s and Trousseau’s sign, seizures, easily fatigued, depression, anxiety, confusion; Cardiac: hypotension, ECG changes; Respiratory: laryngeal spasm, bronchospasm, stridor. Hypercalcemia: Neuromuscular: lethargy, muscle weakness, depressed deep tendon reflexes, decreased memory, confusion, personality changes, psychosis, stupor, coma, bone pain, fractures; Gastrointestinal: anorexia, nausea, vomiting, increased thirst, constipation. Hypophosphatemia: Neuromuscular: muscle weakness, tremors, paresthesia, bone pain, diminished reflexes, seizures, delirium, hallucinations; Hematopoietic: tissue hypoxia, possible bleeding, possible infection; Cardiac: weak pulse; Respiratory: hyperventilation, respiratory weakness; Gastrointestinal: anorexia, dysphagia. Hyperphosphatemia: Neuromuscular: tetany, hyperreflexia, muscle weakness, flaccid paralysis, painful joints; Cardiac: tachycardia; Gastrointestinal: nausea, vomiting, abdominal cramps; Integumentary: dry, itchy skin. Vascular Access Assessment Inspection: Assess for continuity of skin color, signs and symptoms of infection/inflammation, edema, rash or unhealed scars, broken skin or bleeding. Palpation: Feel for thrill over and around the vascular access, pulses above and below the access, capillary refill, and continuity of skin temperature. Auscultation: Listen for bruit over and around the vascular access.