Med Surg Chapter 16
The weight of a client with congestive heart failure is monitored daily and entered into the medical record. In a 24-hour period, the client's weight increased by 2 lb. How much fluid is this client retaining?
1 L; A 2-lb weight gain in 24 hours indicates that the client is retaining 1L of fluid.
diagnostic findings of metabolic acidosis
ABG values usually show decreased pH and plasma bicarbonate HCO3 Initially PaCO2 is normal, a condition referred to as uncompensated state
A client with excess fluid volume and hyponatremia is in a comatose state. What are the nursing considerations concerning fluid replacement?
Administer small volumes of a hypertonic solution.
Signs and Symptoms of Fluid Volume Deficit
BP low; weight loss >2lb/24 hr Temp elevated Pulse rapid, weak, thready respirations rapid, shallow urine scant, dark yellow stool dry, small volume kin warm, flushed, dry mucous dry, sticky Eyes sunken mental state sleepy jugular veins flat
Hypovolemia
Blood volume is low; electrolytes usually depleted, lethargic, depressed or vomiting. Urine specific gravity >1.030 Have dementia, fever, difficulty swallowing or diarrhea, cannot speak to communicate their needs, eat poorly, weakness, paralysis or limited range of motion, take diuretics, laxatives or drugs that Inuit cell hydration or receive tube feeding with additional installations of water
The nurse is providing care for a client with chronic obstructive pulmonary disease (COPD). When describing the process of respiration the nurse explains how oxygen and carbon dioxide are exchanged between the pulmonary capillaries and the alveoli. The nurse is describing what process?
Diffusion; is the natural tendency of a substance to move from an area of higher concentration to one of lower concentration. It occurs through the random movement of ions and molecules. Examples of diffusion are the exchange of oxygen and carbon dioxide between the pulmonary capillaries and alveoli and the tendency of sodium to move from the ECF compartment, where the sodium concentration is high, to the ICF, where its concentration is low.
The nurse is assigned to care for a client with a serum phosphorus concentration of 5.0 mg/dL (1.61 mmol/L). The nurse anticipates that the client will also experience which electrolyte imbalance?
Hypocalcemia; elevated serum phosphorus concentration. Hyperphosphatemia is defined as a serum phosphorus that exceeds 4.5 mg/dL (1.45 mmol/L). Because of the reciprocal relationship between phosphorus and calcium, a high serum phosphorus concentration tends to cause a low serum calcium concentration.
Which could be a potential cause of respiratory acidosis?
Hypoventilation respiratory acidosis is always due to inadequate excretion of CO2, with inadequate ventilation, resulting in elevated plasma CO concentration, which causes increased levels of carbonic acid. In addition to an elevated PaCO2, hypoventilation usually causes a decrease in PaO2.
The nurse is evaluating a newly admitted client's laboratory results, which include several values that are outside of reference ranges. Which of the following alterations would cause the release of antidiuretic hormone (ADH)?
Increased serum sodium; causes increased osmotic pressure, increased thirst, and the release of ADH by the posterior pituitary gland. When serum osmolality decreases and thirst and ADH secretions are suppressed, the kidney excretes more water to restore normal osmolality. Levels of potassium, hemoglobin, and platelets do not directly affect ADH release
The nurse is caring for a client undergoing alcohol withdrawal. Which serum laboratory value should the nurse monitor most closely?
Magnesium; Chronic alcohol abuse is a major cause of symptomatic hypomagnesemia in the United States. The serum magnesium concentration should be measured at least every 2 or 3 days in clients undergoing alcohol withdrawal.
The nurse is caring for a client with severe diarrhea. The nurse recognizes that the client is at risk for developing which acid-base imbalance?
Metabolic acidosis; The client is at risk for developing metabolic acidosis. Metabolic acidosis is caused by diarrhea, lower intestinal fistulas, ureterostomies, and use of diuretics; early renal insufficiency; excessive administration of chloride; and the administration of parenteral nutrition without bicarbonate or bicarbonate-producing solutes (e.g., lactate).
A nurse caring for a patient with metabolic alkalosis knows to assess for the primary, compensatory mechanism of:
The respiratory system compensates by decreasing ventilation to conserve CO2 and increase the PaCO2.
manifestations of respiratory alkalosis
acute anxiety, high fever, thyrotoxicosis (overactive thyroid), early salicylate poisoning, hypoxemia, or mechanical ventilation
BNP
brain natriuretic peptide synthesized in the ventricles of the heart despite originally being attributed to the brain Are released in response to over-stretching of the atrial and ventricular walls Are vasodilators that reduce blood volume by promoting the excretion of sodium, inhibiting the release of renin
hyperkalemia
cn occur with severe renal failure in which the kidneys cannot excrete potassium; severe burns; administration of potassium sparing diuretics; overuse of potassium supplements, salt substitutes or some diet sodas, or potassium rich foods, crushing injuries; Addison disease and rapid administration of parenteral potassium salts
dependent edema
edema in body areas most affected by gravity, such as feet, ankles, sacrum or buttocks in clients confined to bed. Jugular neck veins may appear prominent when client sits. Eventually, fluid congestion in the lungs leads to moist breath sounds
Oral fluid Intake
can range from 1800 and 3000 ml/day
hyponatremia
causes include profuse diaphoresis, excessive ingestion of plain water or administration of nonelectrolye IV fluids, profuse diuresis, loss of GI secretion, prolonged vomiting, GI suctioning, draining fistulas and Addison disease
Aldosterone
causes kidneys to reabsorb sodium, which in turn increased blood volume and BP
hypomagnesemia
condition that result include chronic ETOH, diabetic ketoacidosis, severe renal disease, severe burns, severe malnutrition, pregnancy induced hypertension, intestinal malabsorption syndromes, excessive diuresis, hyperaldosteronism, and prolonged gastric suction
signs and sx of metabolic acidosis
deep and rapid breathing (Kussmauls breathing), compensatory mechanize to rid body of CO2 and thus prevent carbonic acid from forming. anorexia, N/V, headache, confusion, fusing, lethargy, malaise, drowsiness, abdominal pain or discomfort and weakness
manifestations of hypercalcemia
deep bone pain, constipation, anorexia, nausea, vomiting, pleura, thirst, pathologic factories, and mental changes such as decreased memory and attention span. calcium level is above 10 mg, and ionized calcium level is above 5.4
manifestations of hyperkalemia
diarrhea, nausea, muscle weakness, paresthesias, and cardiac arrhythmias. Can cause unique changes in ECG serum potassium level is above 5.5
Electrolytes, Acids and Bases
electrolytes are substances that carry an electrical charge when dissolved in fluid Acids are substances that release hydrogen into fluid Bases are substances that bind w/hydrogen
Metabolic alkalosis med mgt
eliminating the cause. prescribe potassium (potassium salt), prescribing sodium chloride
trousseau sign
evidenced by a spasm of fingers, hand, and wrist when blood pressure cuff is inflated to al level between the clients systolic and diastolic blood pressure for 3 minutes
manifestations of hypermagnesemia
experience flossing, warmth, hypotension, lethargy, drowsiness, bradycardia, muscle weakness, depressed respirations and coma serum amp level is above 2.1
Body fluid primary sources
food and liquids
Pathophysiology and Etiology of Hypovolemia
inadequate fluid intake, fluid loss in excess of fluid intake such as with hemorrhage, prolonged committing or diarrhea, wound loss with burn injury or profuse urination or perspiration and translocation of fluid to compartments where it is trapped such as the abdominal cavity or interstitial spaces (3rd spacing)
Factors of Metabolic Alkalosis
increase base bicarbonate include excessive oral or parenteral use of bicarbonate containing drugs or other alkaline salts, a rapid decrease in extracellular fluid volume & loss of hydrogen and chloride ions (vomiting, prolonged gastric suctioning, hyperkalemai, hyperaldosteronism) the result is retention of sodium bicarbonate and increased bas bicarbonate
Early signs of hypervolemia include
increased breathing effort and weight gain.
pitting edema
indentation in the skin after compression, may be noted 1+ slight indentation 2mm, normal contours 2+ deeper pit after pressing 4mm, last longer 3+ deep pit 6mm, remains several seconds after 4+ deep pit, 8mm remains for a prolonged time/minutes Brawny Edema-fluid can no longer be displaced secondary to excessive interstitial fluid accumulation, no pitting, tissue firm/hard, skin shiny warm and moist
metabolic acidosis
is a condition that results in decreased plasma pH because of increased organic acids or decreased bicarbonate it occurs during shock and cardiac arrest
Passive diffusion
is a physiologic process by which dissolved substances move from an area of high concentration to an area of lower concentration thru a semipermeable membrane; like osmosis remains unchanged once equilibrium occurs
glucose
is an example of a substance that requires facilitated diffusion because once in the blood stream, glucose cannot permeate cell walls. it is available to cells in combination with insulin and glucose; without insulin, glucose transport is very low but in the the presence of insulin glucose transport is rapidly stimulated
hypernatremia
is excess sodium in the blood; causes include profuse watery diarrhea, excessive salt intake without sufficient water intake, high fever, decreased water intake, debilitated, unconscious, or developmentally delayed, excessive administration of solutions that contain sodium, excessive water loss without an accompanying loss of sodium and severe burns
facilitated diffusion
is the process in which certain dissolved substances require the assistance of a carrier molecule to pass from one side of a cellular membrane to the other
hypervolemia
means a high volume of water in the intravascular fluid compartment; caused by fluid intake that exceeds fluid loss; such as from excessive oral intake or rapid IV infusion of fluid a consequence of heart failure when the heart cannot adequately distribute fluid to the kidneys for filtration can result from inadequate fluid elimination accompany kidney disease; also can occur 2d'ry to excessive salt intake, adrenal glad dysfunction or corticosteroid drugs -prednisolone-
acidosis
means excessive accumulation of acids or excessive loss of bicarbonate in body fluids
alkalosis
means excessive accumulation of bases or loss of acid in body fluid can stem from metabolic or respiratory alterations
manifestations of hyponatremia
mental confusion, muscular weakness, anorexia, restlessness, elevated body temp, tachycardia, nausea, vomiting, and personality changes. lethargy, headache, confusion, apprehension, seizures, coma serum sodium level is below 135
A client who is semiconscious presents with restlessness and weakness. The nurse assesses a dry, swollen tongue; body temperature of 99.3 °F; and a urine specific gravity of 1.020. What is the most likely serum sodium value for this client? 165 mEq/L
normal sodium level is 135- 145 mEq/L (135-145 mmol/L). In hypernatremia, the serum sodium level exceeds 145 mEq/L (145 mmol/L) and the serum osmolality exceeds 300 mOsm/kg (300 mmol/L). The urine specific gravity and urine osmolality are increased as the kidneys attempt to conserve water (provided the water loss is from a route other than the kidneys). Body temperature may increase mildly, but it returns to normal after the hypernatremia is corrected.
Magnesium Gerontologic Considerations
older adults may use magnesium sulfate soaks, leading to absorption of magnesium through the skin
hypokalemia
potassium wasting diuretics such as furosemide(Lasix), ethacrynic acid (Edercin), and hydrocaholorothiazide (HydroDIURIL) Loss of fluid from the GI tract with severe vomiting or diarrhea, draining intestinal fistulae, or prolonged suctioning causes potassium deficit Large doses of corticosteroids, IV administration of insulin and glucose and prolonged administration of non electrolyte parenteral fluids can deplete potassium
ANP
produced by the hearts atrial muscle Are released in response to overstretching of the atrial and ventricular walls Are vasodilators that reduce blood volume by promoting the excretion of sodium, inhibiting the release of renin
filtration
promotes the movement of fluid & some dissolved substances through a semipermeable membrane according to pressure differences; it relocates water and chemicals from an areas of high pressure to an area of low pressure
active transport
requires an energy source, a substance called adenosine triphosphate (ATP) to drive dissolved chemicals from an area of low concentration to an area of higher concentration; the opposite of pave diffusion ex. active transport is the sodium potassium pump system
respiratory acidosis conditions
respiratory acidosis include pneumothorax, hemthorax, pulmonary edema, acute bronchial asthma, atelectasis, hyaline membrane disease or other forms fo respiratory distress in newborn, pneumonia, some drug o/d, and head injuries Disorders: emphysema, bronchiectasis, bronchial asthma, and cystic fibrosis
nursing management hypovolemia
respond to thirst, consume at 8-10 (8oz) glasses of fluid daily, drink water, avoid ETOH/caffeine, do not restrict salt or sodium, rise slowly from a sitting or lying position to avoid dizziness/injury
respiratory alkalosis
results from carbonic acid deficit that occurs when rapid breathing releases more CO2 with expired air. Tachypnea (rapid breathing)
Metabolic Alkalosis
results in increased plasma pH because of accumulated base bicarbonate or decreased hydrogen ion concentrations.
dehydration
results when the volume of body fluid is reduced in both extracellular and intracellular compartments Most common in older adults; reduced thirst sensation causing them to drink less water
baroreceptors
sensitive to change in BP; are stretch receptors in the aortic arch & carotid sinus that signal the brain to release ADH when blood volume decreases by 10%, systolic BP falls below 90, or right atrium is underfilled; signal brain to suppress ADH when blood volume increases, systolic BP rises or right atrium is overfilled
serum osmolaity
specialized neurons that sense concentration of substances in blood; when blood becomes overly concentrated osmoreceptors stimulate hypothalamus to synthesize ADH released by the posterior lobe of pituitary gland; ADH inhibits urine formation by increasing reabsorption of water in nephrons of the kidneys
manifestations of hypomagnesemia
tachycardia, and other cardiac arrhythmias, neuromuscular irritability, paresthesias of the extremities, leg and foot cramps, hypertension, mental changes, positive Chvostek, and Trousseau signs, dysphagia, and seizures. Magnesium level is below 1.3 (1.3 -2.1)
Renin
the transformation of angiotensinogen to angiotensin I to angiotensin II; causes vasoconstriction and raised BP; also stimulates release of aldosterone from adrenal cortex
manifestations of hypernatremia
thirst, dry, sticky mucous membranes, decreased urine output, even rough dry tongue and lethargy which can progress to coma if the excess is severe sodium level is above 145
manifestations of hypocalcemia
tingling in extremities and area around mouth, muscle and abdominal cramps, positive Chvostek sign (spasms of facial muscles when facial nerve is tapped, carpopdeal spasms referred to trousseau sign, mental changes, laryngeal spasms with airway obstruction, tetany (muscle twitching), seizures, bleeding, and cardiac arrhythmias. calcium level is below 8.8
chvostek sign
unilateral spasm of facial muscles, is elicited by tapping over the facial nerve which lies approx 2 cm anterior to the earlobe
A client has been diagnosed with an intestinal obstruction and has a nasogastric tube set to low continuous suction. Which acid-base disturbance is this client at risk for developing?
Metabolic alkalosis is a clinical disturbance characterized by a high pH and a high plasma bicarbonate concentration. The most common cause of metabolic alkalosis is vomiting or gastric suction with loss of hydrogen and chloride ions. Gastric fluid has an acid pH, and loss of this acidic fluid increases the alkalinity of body fluids.
A nurse in the Medical ICU has orders to infuse a hypertonic solution into a patient with low blood pressure. This solution will increase the number of dissolved particles in the patient's blood, creating pressure for fluids in the tissues to shift into the capillaries and increase the blood volume. What term or terms are associated with this process?
Osmosis and osmolality
A nurse is caring for a client admitted with a diagnosis of exacerbation of myasthenia gravis. Upon assessment of the client, the nurse notes the client has severely depressed respirations. The nurse would expect to identify which acid-base disturbance?
Respiratory acidosis; is always from inadequate excretion of CO2 with inadequate ventilation, resulting in elevated plasma CO2 concentrations. Respiratory acidosis can occur in diseases that impair respiratory muscles such as myasthenia gravis.
The nurse is caring for an older adult client who has been involved in a motor vehicle accident. The client's labs indicate minimally elevated serum creatinine levels. The nurse should assess for signs of what change?
Substantially reduced renal function
A newly graduated nurse is admitting a client with a long history of emphysema. The nurse learns that the client's PaCO2 has been between 56 and 64 mm Hg for several months. Why should the nurse be cautious administering oxygen?
Using oxygen may result in the client developing carbon dioxide narcosis and hypoxemia.
Signs and Symptoms of Fluid Volume Excess
Weight gain >2lb 24 hr; BP high Temp high Pulse full, bounding Respirations moist, labored Urine light yellow stool bulky skin cool, pale, moist skin pitting & dependent edema eyes swollen lungs crackles, gurgles jugular neck distended mental state anxious breathing dyspnea, orthopnea
hypermagnesemia
a consequence of renal failure, Addison disease, excessive use of antacids or laxatives that contain magnesium, and hyperparathyroidism
Hypervolemia/Circulatory Overload
a fluid volume that exceeds what is normal for the intravascular space and can potentially compromise cardiopulmonary function. The excess volume raises BP and causes the heart to increase its force of contraction
Hemoconcentration
a high ratio of blood components in relation to watery plasma, increased the potential for blood clots and urinary stones and compromises the kidneys ability to exert nitrogen wastes; ex change in mentation
renin angiotensin aldosterone system
a series of chemicals released to increase both BP & blood volume; triggered by juxtaglomerular apparatus (ring of pressure sensing cells that surround arterioles leading to each glomerulus in kidneys arterial blood supplying glomeruli is reduced juxtaglomerular cells release renin
filtration (kidney)
also affects how the kidneys excrete fluid and wastes and then selectively reabsorb water & other chemicals that need to be conserved. Kidney filter about 180L of fluid from blood daily; 1-1.5 L is reabsorbed
Acids
also increase in starvation and diabetic ketoacidosis, as fatty acids accumulate because the body cannot use glucose for energy Accumulation of acids may follow renal failure because kidneys cannot reabsorb bicarbonate to buffer blood Accumulate with aspirin o/d or profuse diarrhea, & intestinal fluid through wound drainage
Assessment findings of metabolic alkalosis
anorexia, nausea, vomiting, circumoral paresthesias, confusion, carpopedal spasm, hypertonic reflexes, and tetany. RR and volume decrease in compensatory effort to produce more carbonic acid to increase and restore acidic level in blood ABG show increased pH & HCO3 and normal PaCO2 levels
natriuretic peptides
are hormone like substances that act in opposition to the renin angiotensin aldosterone system
hypercalcemia
associated with parathyroid gland tumors, multiple fractures, Paget disease, hyperparathyroidism, excessive doses of vitamin D, prolonged immobilization, some chemo agents, and certain malignant diseases (multiple myeloma, acute leukemia, lymphomas)
assessment finding of respiratory acidosis
extreme respiratory insufficiency, frantic efforts to breathe, breathe slowly or irregularly or stop breathing. Expiratory volumes decreased Lungs sounds moist or absent in some lobes Tachycardia usually present and cardiac arrhythmias develop Cyanosis appearance to skin Behavioral changes Tremors, muscle twitching, flushed skin headache, weakness, stupor and coma ABG value show a < pH and > PaCO2 above 45
Manifestations of hypokalemia
fatigue, weakness, anorexia, nausea, vomiting, cardiac arrhythmias, leg cramps, muscle weakness, and paresthesias (abnormal sensations), changes in ECG severe cases result in hypotension, flaccid paralysis, and even death from cardiac or respiratory arrest potassium is below 3.5
What to check for hypervolemia
have altered cardiac or kidney function have increased ADH production, which sometimes accompanies brain trauma are receiving corticosteroid therapy, large rapid volumes of IV fluid or IV colloid solutions consume oral fluids to excess, such as clients w/schizophrenia who can develop water intoxication ingest high salted food or large amounts of sodium
assessment findings of respiratory alkalosis
increased respiratory rate, include light headedness, numbers and tingling of fingers and toes, circumoral paresthesias, sweating, panic, dry mouth and in severe cases conclusions. ABG values indicate a pH above 7.45 and PaCO2 below 35mm tx aims to correct the cause of rapid breathing (using a paper bag)
osmoreceptors
regulated in the hypothalamus; fluid volume is regulated primarily by the excretion of water in the form of urine and promotion of thirst; senses thirst when extracellular volume < by 700mL or about 2% of body wt
Hypocalcemia
vitamin D deficiency, hypoparathyroidism, severe burns, acute pancreatitis, certain drugs such as corticosteroids, rapid administration of multiple units of blood that contain an anti calcium advice, intestinal malabsorption disorders and accidental surgical removal of parathyroid glands (normal 9 - 11) (ionized 4.4 - 5.4)
nursing assessment hypovolemia
weight daily at the same time same scale and dressed similarly, report a loss of 2 lb or more in 24 hrs, recovered vital signs regularly, check for postural hypotension a drop in systolic pressure of 15 mm after rising from a sitting or recumbent position, ask about thirst, examination skin for dryness, assess turgor (elasticity), look for gross sources of fluid loss: vomiting, diarrhea, bleeding, wound drainage, GI suctioning and diaphoresis, note medications
circulatory volume
when circulatory volume is decreased, BP falls and the heart compensates by increasing the heart rate to maintain adequate cardiac output BP falls w/postural changes
C-type
which is made in the brain, c-type natriuretic peptide
respiratory acidosis
which may be either acute or chronic, is caused by excess carbonic acid, which causes the blood pH to grow below 7.35