Ch. 52 Fluid, Electrolyte, and Acid-Base Balance
a. 135
A 42 year old client has chronic hyponatremia which requires weekly blood labs to keep him from lapsing into convulsions or a coma. What is the level of serum sodium below which convulsions or coma can occur? a. 135 b. 145 c. 140 d. 142
c. Monitoring respiratory status for signs and symptoms of pulmonary complications.
A priority nursing intervention for a client with hypervolemia involves which of the following? a. Establishing I.V. access with a large-bore catheter b. Drawing a blood sample for typing and crossmatching c. Monitoring respiratory status for signs and symptoms of pulmonary complications d. Encouraging the client to consume sodium-free fluids.
a. BUN to creatinine ratio of 24:1
A volume depleted patient would present ith which of the following diagnostic lab results? a. BUN to Creatinine ratio of 24:1 b. Urinary output of 1.2 L/24 hours c. Urine specific gravity of 1.02 d. Capillary refill time of 3 seconds
-Maintaining fluid balance -Contributing to acid-base regulation -Facilitating enzyme reactions -Transmitting neuromuscular reactions
Electrolytes are important for (4)
b. Mental confusion
An older man is admitted to the medical unit with a diagnosis of dehydration. Which signs or symptom is most representative of a sodium imbalance? a. Hyperreflexia b. Mental confusion c. Irregular pulse d. Muscle weakness
b. Weak, rapid pulse
An older nursing home resident has refused to eat or drink for several days and is admitted to the hospital. The nurse should assess for which of the following? a. Increased blood pressure b. Weak, rapid pulse c. Moist mucous membranes d. Jugular vein distention
Respiratory acidosis
Any condition that causes carbonic acids to increase, carbon dioxide to be retained, and pH to fall below 7.35
c. Extreme anxiety
Before seeing a newly assigned client with respiratory alkalosis, a nurse quickly reviews the client's medical history. Which condition is a predisposing factor for respiratory alkalosis? a. Myasthenia gravis b. Type 1 diabetes mellitus c. Extreme anxiety d. Opioid overdose
22 to 26 mEq/L
Bicarbonate (HCO3-)
-Must use NSS -Must use Y-type tubing -Use 18-20G Jelco when possible -infused 2-4 hours (no longer than 4) -Run slow (start at 1-2 mL per min for 1st 15 min)
Blood transfusion musts
8.5 - 10.5 mg/dL
Calcium (Ca+) Normal Levels
Trousseau's sign
Carpopedal spasm induced by inflating the blood pressure cuff above systolic pressure
renal failure diabetic ketoacidosis starvation
Causes of metabolic acidosis
Prolonged vomiting, ingestion of antacids
Causes of metabolic alkalosis
Suppressed respiratory center asthma COPD anesthesia narcotic OD
Causes of respiratory acidosis (hypercapnia)
Anxiety-hyperventilation
Causes of respiratory alkalosis
95-108 mEq/L
Chloride (Cl-) Normal Levels
Osmolality
Concentration of solutes in body fluids
Respiratory alkalosis
Condition that occurs when carbonic acid levels fall, more carbon dioxide than normal is exhaled, and pH rises to greater than 7.45
Chvostek's sign
Consists of twitching of muscles supplied by the facial nerve when the nerve is tapped about 2 cm anterior to the earlobe, just below the zygomatic arch.
Renal disease Cardiovascular disease DM, Cancer, COPD Confusion leading to poor fluid intake Vomiting, Diarrhea, Nasogastric suctioning Burns Medications
Disturbances in fluid volume (7)
b. Hypoventilation
Which of the following would be a potential cause of respiratory acidosis? a. Vomiting b. Hypoventilation c. Diarrhea d. Hyperventilation
Age Gender and body size Environmental temperature Lifestyle
Factors affecting body fluid, electrolytes and acid-based balance
2,500 mL/day through fluids and foods
Fluid intake
Obligatory losses
Fluid losses are required to maintain normal body function (kidney filtration of waste, etc) approx. 500 mL/day
Third space syndrome
Fluid moves to an area not readily accessible as ECF (Puffy patient without edema)
Urine: 1,400-1,500 mL/day (0.5 mL/kg/hr) Feces: 100-200 mL/day Insensible Fluid loss - skin (400 mL/day) & lungs (400 mL/day) (NONMEASURABLE) Obligatory losses: approx. 500 mL/day
Fluid output (URINE, FECES, INSENSIBLE, OBLIGATORY)
Extracellular fluid (ECF)
Found outside the cells
22-26
HCO2 (bicarbonate) normal range
Acidosis
Happens when the ratio of bicarbonate to carbonic acid is upset with the depletion of bicarbonate
Hypertonic
Higher osmolality than ECF
Antidiuretic hormone (ADH) Renin-angiotensin aldosterone system Atrial natriuretic factor
Hormones that maintain homeostasis
K+ above 5.0 mEq/L
Hyperkalemia
Mg2+ above 2.5
Hypermagnesemia
Na+ above 145 mEq/L
Hypernatremia
Dehydration
Hyperosmolar fluid imbalance; water lost from body leaving client with excess sodium
PO4- above 4.6
Hyperphosphatemia
K+ below 3.5 mEq/L
Hypokalemia
Mg2+ below 1.5
Hypomagnesemia
Na+ below 133 mEq/L
Hyponatremia
PO4- below 2.5
Hypophosphatemia
Hypervolemia
Increased blood volume; FVE
Cations
Ions that carry a positive charge
-Osmolality -Urine specific gravity -Blood urea nitrogen -Creatinine -Hematocrit
Lab tests for evaluating fluid status
Hypotonic
Lower osmolality than ECF
1.5 - 2.5 mEq/L
Magnesium (Mg2+) Normal Levels
Kidneys and Hormones
Maintaining homeostasis
Hypovolemia
May be caused by decreased fluid intake, bleeding
Decreased pH, normal PaCO2, Decreased HCO3
Metabolic Acidosis
Increased pH, normal PaCO2, Increased HCO3
Metabolic Alkalosis
-Diet and excreted in urine -Some are not stored and must be consumed daily
Most electrolytes obtained through (2)
Anions
Negatively charged ions
10-20 mg/dL (3.6 to 7.2 mmol/L)
Normal BUN levels
0.7 to 1.4 mg/dL (62 to 124 mmol/L
Normal creatinine levels
42% to 52% for males 35 to 47% for females
Normal hematocrit levels (males and females)
275 to 300
Normal osmolality levels
1.010 to 1.025
Normal urine specific gravity levels
Metabolic acidosis
Occurs when bicarbonate levels are low in relation to the amount of carbonic acid in the body
Fluid volume deficit (FVD)
Occurs when body loses both water and electrolytes from the ECF in similar proportions
Metabolic alkalosis
Occurs when the amount of bicarbonate in the body exceeds the normal 20-1 ratio
Fluid volume excess (FVE)
Occurs when the body retains both water and sodium in similar proportions to normal ECF
2.5 - 4.6 mg/dL
Phosphate (PO4-) Normal Levels
3.5 - 5.0 mEq/L
Potassium (K+) Normal Levels
Vegetables: Avocado, raw carrot, baked potato, raw tomato, spinach. Meats and Fish: Beef, Cod, Pork, Veal Fruits: Dried fruits, banana, apricot, cantaloupe, orange Beverages: Milk, orange juice, apricot nectar Chocolate and Sphaghetti sauce
Potassium rich foods
Hydrostatic pressure
Pressure exerted by a fluid within a closed system against the walls of the contain in which it is contained
Colloid osmotic pressure
Pressure exerted by plasma proteins which pull water from the interstitial space into the vascular compartment when necessary
Buffer Ex. Antacid
Prevent excessive changes in pH by binding with or releasing hydrogen ions.
Arterial blood gases (ABGs)
Provide an accurate reflection of the gas exchange in the pulmonary system
Buffers Respiratory regulation Renal regulation
Regulation of acid-base balance (7.35-7.45) (3)
Decreased pH, Increased PaCO2, normal PaO2
Respiratory Acidosis
Increased pH, decreased PaCO2, normal PaO2
Respiratory Alkalosis
Alkalosis
Rise in pH that can be due to depletion of carbonic acid
Crystalloids
Salts that dissolve readily into true solutions
Isotonic
Same osmolality as ECF
d. "I will stop using my salt substitute."
Which client statement indicates a need for further teaching regarding treatment for hypokalemia? a. "I will use avocado in my salads." b. "I will be sure to check my heart rate before I take my digoxin." c. "I will take my potassium in the morning after eating breakfast." d. "I will stop using my salt substitute."
135 - 145 mEq/L
Sodium (Na+) Normal Levels
Acid
Substance that releases hydrogen ions in solution
a. Facial
Which nerve is implicated in the Chvostek's sign? a. Facial b. Hypoglossal c. Optic d. Spinal accessory
1. PaO2: 50-70 mmHg **(should be 80-100 mmHg)
The following are normal values of arterial blood gases EXCEPT: 1. PaO2: 50-70 mmHg 2. pH: 7.35-7.45 3. PaCO2: 35-45 mmHg 4.HCO3: 22-26 mEq/L
Renal regulation
The kidneys are the ultimate long-term regulator of acid-base balance. Slow to respond to changes, but permanent responses.
Respiratory regulation
The lungs help regulate acid-base balance by eliminating or retaining carbon dioxide, also by altering the rate and depth of respirations
3. Not as visible, because it will tend to roll away from the needle.
The nurse who is starting an intravenous infusion should avoid using all of the following EXCEPT a vein that is: 1. Damaged by previous use, phlebitis, infiltration, or sclerosis. 2. In an area of flexion. 3. Not as visible, because it will tend to roll away from the needle. 4. Continually distended with blood, knotted or tortuous.
Hydrostatic Pressure
The pressure a liquid exerts on the sides of the container that holds it' also called filtration force
pH
The relative acidity or alkalinity of a solution
1,300 mL/day
Total insensible and obligatory output
c. pH rises to greater than 7.45
Which of the following events occurs when an individual hyperventilates? a. Less carbon dioxide than normal is exhaled b. Carbonic acid levels increase c. pH rises to greater than 7.45 d. More oxygen than normal is exhaled
1. Vomiting for 3 days 2. Has a nasogastric tube 4. Refusal to eat or drink/starvation 5. Patient with c/o vomiting and diarrhea x 2 days with lethargy and c/o leg cramps 6. Alcoholic
Which patient is at most risk for a fluid and/or electrolyte imbalance? Select all that apply. 1. vomiting for 3 days 2. Has a nasogastric tube 3. Eating lost of high fat content foods 4. Refusal to eat or drink/starvation 5. Patient with c/o vomiting and diarrhea x 2 days with lethargy and c/o leg cramps 6. Alcoholic 7. Smoker
a. Dilute the infusion
You are caring for a c lient with severe hypokalemia. The physician has ordered IV potassium to be administered at 10 mEq/hr. The client complains of burning along their vein. What should you do? a. Dilute the infusion b. Switch to an oral formulation c. Increase the speed of transfusion d. Change the electrolyte
b. Limit sodium and water intake
Your client has a diagnosis of hypervolemia. What would be an important intervention that you would initiate? a. Give medications that promote fluid retention b. Limit sodium and water intake c. Assess for dehydration d. Teach client behaviors that decrease urination
Cantaloupe - highest food on menu in potassium
Your patient is on Lasix, a potassium depleting diuretic and this morning the potassium level was 3.4. What foods can you instruct him to choose from the dinner menu and why? -Baked chicken -Green beans -Cantaloupe -Iced tea
35-45
paCO2 normal range
80-100
paO2 normal range
Colloids
substances that do not readily dissolve in true solutions
a. BUN of 23 mg/DL b. Serum osmolality of 310 mOsm/kg c. Serum Na of 18 mEq/L e. Urine specific gravity of 1.02
A 54-year-old male patient is admitted to the hospital with a case of severe dehydration. The nurse reviews the patient's laboratory results. Which of the following results are consistent with the diagnosis? Select all that apply. a. BUN of 23 mg/dL b. Serum osmolality of 310 mOsm/kg c. Serum Na of 18 mEq/L d. Serum glucose 90mg/dL e. Urine specific gravity of 1.02 f. Hematocrit level of 48%
a. Third-spacing
A 57-year-old homeless female with a history of alcohol abusel has been admitted to your hospital unit. She was admitted with signs and symptoms of hypovolemia - minus the weight loss. She exhibits a localized enlargement of her abdomen. What condition could she be presenting? a. Third-spacing b. Pitting edema c. Anasarca d. Hypovolemia
d. No, sodium intake should be restricted
A 64-year-old client is brought into the clinic with thirsty, dry, sticky mucous membranes, decreased urine output, fever, a rough tongue, and lethargy. Serum sodium level is above 145 mEq/L. Should the nurse start salt tablets when caring for this client? a. Yes, this will correct the sodium deficit b. Yes, along with the hypotonic IV c. No, start with the sodium chloride IV d. No, sodium intake should be restricted
a. Trousseau's sign
A client has a serum calcium level of 7.2 mg/dL. During the physical examination, the nurse expects to assess: a. Trousseau's sign b. Homans' sign c. Hegar's sign d. Goodell's sign
d. metabolic alkalosis
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? a. Respiratory acidosis. b. Respiratory alkalosis c. Metabolic acidosis d. Metabolic alkalosis
d. Neuromuscular
A client is admitted to the hospital for hypocalcemia. Nursing interventions relating to which system would have the highest priority? a. Renal b. Caridac c. Gastrointestinal d. Neuromuscular
d. electrocardiogram (ECG) results (can indicate potentially lethal arrhythmias such as Vfib)
A client is taking spironolactone (Aldactone) to control her hypertension. Her serum potassium level is 6 mEq/L. For this client, the nurses' priority should be to assess her: a. neuromuscular function. b. bowel sounds c. respiratory rate d. electrocardiogram (ECG) results
d. Potassium (Norm is 3.8 to 5.5 mEq/L)
A client with pancreatic cancer has the following blood chemistry profile: Glucose, fasting: 204 mg/dL; blood urea nitrogen (BUN): 12 mg/dL; Creatinine: 0.9 mg/dL; Sodium: 136 mEq/L; Potassium: 2.2 mEq/L; Chloride: 99 mEq/L; CO2: 3 mEq/L. Which result should the nurse identify as critical and report immediately? a. CO2 b. Sodium c. Chloride d. Potassium
b. Review the results of serum electrolytes
A man brings his elderly wife to the emergency department. He states that she has been vomiting and has had diarrhea for the past 2 days. She appears lethargic and is complaining of leg cramps. What should the nurse do first? a. Start an IV. b. Review the results of serum electrolytes c. Offer the woman foods that are high in sodium and potassium content d. Administer an antiemetic.
4. Be sure the MD sees this child immediately
A mother presents to the MD office with her infant with c/o vomiting and diarrhea for 2 days. What should the nurse do for this child? 1. Have the mom try to feed pedialyte while in the office 2. Measure the urinary output for 24 hours 3. Have mom count diapers used while in the office 4. Be sure the MD sees this child immediately
d. Hypercalcemia
A nurse is caring for a client with metastatic breast cancer who is extremely lethargic and very slow to response to stimuli. The laboratory report indicates a serum calcium level of 12.0 mg?dL, a serum potassium level of 3.8 mEq/L, a serum chloride level of 101 mEq/L, and a serum sodium level of 140 mEq/L. Based on this information, the nurse determines that the client's symptoms are most likely associated with which electrolyte imbalance? a. Hyperkalemia b. Hypocalcemia c. Hypokalemia d. Hypercalcemia
d. Fatigue, cramps and weakness
A patient with a diagnosis of colon cancer has undergone a bowel resection with the creation of an ileostomy. The patient's ileostomy ouput has been unexpectedly high in the 2 days since surgery, and the patient's most recent blood work indicates a K+ level of 2.7 mEq/L. This potassium level should prompt the nurse to assess for which of the following physical manifestations? a, Confusion and decreased level of consciousness b. Shortness of breath, rales and peripheral edema c. Dysphagia, tetany, and emotional lability d. Fatigue, cramps, and weakness.
c. "Are you feeling any tingling in your hands or around your mouth?" (Removal of the parathyroid can precipitate hypocalcemia, which often results in tetany)
A patient with a diagnosis of thyroid cancer is postoperative day 1 following a total thyroidectomy in which her parathyroid gland was also removed. When assessing for related electrolytes imbalances, what question should the nurse ask the patient? a. "Do you feel like you're having heart palpitations where your heart feels like it skips a beat?" b. "How thirsty are you feeling right now?" c. "Are you feeling any tingling in your hands or around your mouth?" d. "How would you rate your energy level right now?"