ch 41 fluid, electrolyte, and acid-base balance

cations

+ electric charge -major cations are sodium, potassium, calcium, hydrogen, and magnesium

The nurse is assessing an adult client who has presented to the emergency department with general weakness. The nurse reviews the client's health record to find there is no history of underlying health conditions. The nurse will begin preparing for the insertion of a peripheral intravenous line if which assessment finding(s) are present? Select all that apply.

-The client reports using laxative substances daily. -The client has been vomiting for several days. -The client has a serum potassium level of 2.0 mEq/l (2.0 mmol/l). -The client has severe iron-deficiency anemia.

hypochloremia ECF

-below normal level of chloride in ECF -result from vomiting, diarrhea, drainage of gastric fluid, metabolic alkalosis, diuretic therapy, burns -manifestations: hyperexcitability of muscles, tetany, hyperactive DTRs, fever

Hypophosphatemia

-below-normal serum concentration of inorganic phosphorus in ECF -result from administration of calories to malnourished pts, alcohol withdrawal, diabetic ketoacidosis, hyperventilation, diuretic use -manifestations: slurred speech, dysphagia, decreased DTR, muscle weakness, constipation

major electrolytes: sodium Na -functions -sources and losses -regulation

-chief electrolyte of ECF 135-145 mEq/L function: loss or gain of water; regulates EC fluid volume; role in muscle contraction and transmission of nerve impulses sources and losses: enters through GI tract from dietary sources; lost from GI tract, kidneys, and skin regulation: transported out by sodium-potassium pump

variations in fluid content

-depends on persons age, body fat, and sex -fat cells contain little water/lean tissue is rich in water (more obese a person is, the smaller the percentage of total body water)

fluid balance

-ingestion of liquids provides largest amount of water -water contained in food is second largest source of water for the body -fluid intakes averages 2,600 ml per day -in hypothalamus, thirst control center is stimulated by IC dehydration sensible losses: can be measured; include fluid lost during urination, defecation, and wounds insensible losses: cannot be measured or seen; fluid lost from evaporation through skin

hypocalcemia ECF

-insufficient amount of calcium in ECF, hypoparathyroidism, celiac and Crohn's disease, kidney disease -manifestations: numbness and tingling of fingers, mouth, or feet, tetany, positive trousseau sign, Chvostek sign,

hypomagnesemia ICF

-insufficient amount of magnesium in the ECF -occurs with NG suction, diarrhea, chronic alcohol use, PN, burns -leads to muscle weakness, tremors, hyperactive deep tendon reflexes DTRs (buck wild), tachycardia, high BP

hypokalemia ICF

-insufficient amount of potassium in the ECF -lost through vomiting, gastric suction, alkalosis, diarrhea, use of diuretics -affects skeletal muscles, muscle weakness, leg cramps, arrhythmias, weak pulse, constipation

hyponatremia ECF

-insufficient amount of sodium in the ECF -caused by gain of water -may be lost through vomiting, diarrhea, fistula, sweating, use of diuretics -resulting in confusion, hypotension, edema, muscle cramps and weakness, dry skin

respiratory and renal regulation of H ions/ regular levels

-lungs are primary controller of carbonic acid PaCO2 -bicarbonate is regulated by kidneys HCO3 PaCO2: 35-45 >45 is acid; <35 is base HCO3: 22-26

major electrolytes: Potassium K -function -sources and losses -regulation

-major cation of ICF 3.5-5.0 mEq/L function: role in transmission of electrical impulses in nerve, heart, skeletal, intestinal, and lung tissue, also cardiac muscle sources and losses: leading food sources: fruits and veggies, dried peas and beans, whole grains; lost via kidneys, stool, sweat, emesis regulation: regulated by aldosterone; eliminated by kidneys

hypermagnesemia ICF

1.3-2.1 mEq/L -excess of magnesium in ECF -keeps muscle cells relax after contraction; nerve function -occurs with renal failure, antacids or laxative containing mg -manifestations: n/v, weakness, flushing, lethargy, hypoactive DTRs (calm and quiet), hypotension, bradycardia, weak pulse

major electrolyte: magnesium Mg -function -sources and losses -regulation

1.3-2.3 mEq/L function: neuromuscular; produces vasodilation sources and losses: enters body via GI tract; sources include green veggies, nuts, seafood, whole grains regulation: eliminated by kidneys; regulated by parathyroid hormone

hypernatremia ECF

135-145 mEq/L -function: fluid balance, bp, blood volume -excess of sodium in ECF, dehydration, fluid loss -caused by excess water loss -neurological impairment, muscle contraction, restlessness, weakness, delusions, excessive thirst, edema, increased muscle tone -0.45% NaCl is often used to treat hypernatremia bc it contains a small amount of Na

hyperphosphatemia PO4

2.5-4.5 mg/dL function: bone and teeth, muscle and RBC function, energy metabolism remember calcium and phosphorus are inverse -above-normal serum concentration of inorganic phosphorus in ECF -causes are impaired kidney excretion and hypoparathyroidism -can result in hyperreflexia, anorexia, chvek sign, trossou sign

phosphate PO4 function sources and losses regulation

2.5-4.5 mg/dL function: energy storage; role in muscle and red blood cell function sources and losses: enters GI tract; sources include animal products regulation: eliminated by kidneys; regulated by parathyroid hormone; phosphate and calcium are inversely proportional

bicarbonate HCO3

25-29 mEq/L -regulated by kidneys -regulates blood pH and maintains acid-base balance; bodies buffer system

hyperkalemia ICF

3.5-5 mEq/L -potassium is major intracellular electrolyte; maintains heart and muscle contraction -excess of potassium in ECF -can result from renal failure, certain meds like potassium chloride, heparin, ACE inhibitors, NSAIDs, burn and tissue damage -nerve conduction, muscle contractility, muscle weakness,decreased DTR

Normal pH range

7.35-7.45

major electrolytes: calcium Ca -function -sources and losses -regulation

8.6-10.2 mg/dL function: blood coagulation and transmission of nerve impulses; regulate muscle contraction and relaxation; bones and teeth sources and losses: absorbed from foods; lost via faces and urine; sources include milk, green veggies; fish regulation: excretion by GI tract; regulated by parathyroid hormone and calcitonin

hypercalcemia ECF

8.9-10.5 mg/dL -calcium is major component of bones n teeth, blood clotting, and muscle contraction -excess of calcium in ECF -causes: cancer and hyperparathyroidism, and excessive use of vitamin D and calcium supplements -manifestations: n/v, constipation, bone pain, excessive urination, thirst, confusion, kidney stone formation, decreased DTR -severe hypercalcemia >15 is emergency situation

chloride Cl -function -sources and losses -regulation

97-107 mEq/L function: component of interstitial and lymph fluid sources and losses: enters body GI tract; chloride in diet comes from salt regulation: paired with sodium; regulated by aldosterone; low K level leads to low Cl levels

hyperchloremia ECF

98-108 mEq/L -above-normal level of chloride in ECF -does the same as SODIUM -function: fluid balance, bp, blood volume -result from metabolic acidosis, hypernatremia, hyperparathyroidism -manifestations: tachypnea, weakness, lethargy, decreased cardiac output, N/V, dry tongue, confusion

acidosis

<7.35

alkalosis

>7.45

blood types

A, B, AB, O -A blood have A antigens; B blood have B antigens; AB group have both A and B; type O have neither A or B antigens -AB universal recipients; O are universal donors -Rh negative person must receive blood from another Rh negative person -1 unit over 2 to 3 hours, no longer than 4 hours

The nurse is planning to discontinue a peripherally inserted central catheter (PICC) for a client who is prescribed warfarin therapy. Which intervention will individualize care for this client?

Apply pressure to insertion site for at least 3 minutes.

A client needs an intravenous fluid that will pull fluids into the vascular space. What type of fluid does the nurse prepare to administer as prescribed?

Hypertonic

ROME method

Respiratory Opposite Metabolic Equal full compensation: pH is normal while co2 and hco3 are abnormal partial: all systems abnormal uncompensated: when 1 system is not helping out (ex: pH and hco3 are abnormal but co2 is normal)

A nurse is preparing to re-site a client's IV during the client's hospital stay following a mastectomy. What accurately describes an assessment that should be made before starting the infusion?

The nurse should assess the preferred site, ideally the dorsal and ventral surfaces of the upper extremities.

The nurse writes a a problem-based care plan, citing the client's excess fluid volume. What risk factor does the nurse expect to assess in this client?

acute kidney injury

ion

atom or molecule carrying an electric charge in solution

The nurse is caring for a client who had a parathyroidectomy. Upon evaluation of the client's laboratory studies, the nurse would expect to see imbalances in which electrolytes related to the removal of the parathyroid gland?

calcium and phosphorus

reliable indicator of fluid balance

daily weight

A client who is NPO prior to surgery reports feeling thirsty. What is the physiologic process that drives the thirst factor?

decreased blood volume and intracellular dehydration

cross-matching

determining compatibility between blood specimens

The nurse is preparing to change the IV tubing of a client receiving a peripheral venous IV infusion 5% dextrose and water based on the understanding that IV tubing is generally changed at which interval?

every 96 hrs

hypervolemia

excess of plasma; fluid volume excess (FVE) causes this which is excess water and sodium intake in ECF; causes of fve is malfunction of kidneys (crackles, distended neck veins)

pH

expression of hydrogen ion concentration and resulting acidity of a substance

Extracellular fluid (ECF)

fluid outside cells -sodium, chloride, calcium, and bicarbonate

Intracellular fluid (ICF)

fluid within the cell -potassium, phosphorus, and magnesium

hydrostatic pressure

force exerted by a fluid against the container wall

hypertonic solution

having greater concentration than solution with which it is being compared; water moves out of cells causing cells to shrink -3% saline; given to pts with edema

hypotonic solution

having less concentration than solution with which it is being compared; causes cells to swell and possibly burst -0.45% NaCl

isotonic

having same concentration as solution with which it is being compared 0.9% NS; lactated ringers solution

diffusion

high concentration to low concentration until equilibrium is established; ex: gases like oxygen and co2 exchange in lungs alveoli and capillaries

complications of IV therapy

infiltration: iv fluid leaks into surrounding tissue (swelling, pain, coolness, numbness) IV was not properly placed in vein (put on gloves and remove catheter) extravasation: inadvertent leakage of vesicant (not capable of causing tissue damage) IV solution into surrounding tissue phlebitis: inflammation of vein (heat, redness, tenderness) (should be removed) thrombophlebitis: blood clot in vein hematoma: collection of blood in tissues; "blow the vein'" (blood, hard and painful lump, bruising) speed shock: injected into circulatory system too rapidly (headache, rapid HR, chills, dyspnea) fluid overload: 2 large a volume of fluid infused (engorged neck veins, increased BP, dyspnea) air embolus: air in circulatory system (respiratory distress, cyanosis, decreased BP)

magnesium and phosphorus

inverse

calcium and phosphorus

inverse relationship; high Ca = low Phos

sodium and potassium

inverse relationship; high Na = low K

anions

ions with a negative charge -major anions are chloride, bicarbonate, and phosphate

solvents

liquid holding a substance in solution

hypovalemia

loss of water and solutes in same proportion from ECF space; causes fluid volume deficit (FVD) (sluggish skin turgor)

A client is taking a diuretic such as furosemide. When implementing client education, what information should be included?

low k levels

Homeostasis

maintain a balanced state

metabolic acidosis and alkalosis

metabolic acidosis: deficit of HCO3 in ECF; increase in acidity lungs attempt to increase carbon dioxide by increasing rate n depth of respirations Kidney disease and diarrhea -hyperkalemia, decreased BP, palpitations, metabolic alkalosis: excess of HCO3; decreased acidity respirations become slow and shallow Diuretics, vomiting Tachycardia, tetany, hypokalemia, tremors

active transport

movement of ions or molecules across cell membranes; requires energy

capillary filtration

passage of fluid across the wall of the capillary; results from the force of blood "pushing" against the walls of the capillaries; pushing force is hydrostatic pressure; the pulling force that puts fluid back into capillaries is colloid osmotic pressure

vascular access devices: peripheral venous catheters midline catheters central venous access devices (CVADs)

peripheral venous catheters: reside in veins of peripery that include all extremities; short PIVCs are inserted into superficial veins; long PIVCs are inserted in either superficial or deep peripheral veins; when infusion therapy is <4 days midline catheter: duration of infusion therapy is 5 to 14 days; inserted peripherally into upper arm into basilic, cephalic, or brachial veins CVADs: >15 days; terminates in central venous circulation by superior vena cava near right atrium; require xray confirmation of position after insertion (PICC) for long term (6wks to 6 months) nontunneled: <14 days; tunneled: long term use

A client sustained severe trauma in a motor vehicle accident and has had 26 units of packed red blood cells infused since admission 2 days previously. What does the nurse predict will be prescribed to replace the clotting factors lost with the infusion of large amounts of packed red blood cells?

plasma

A client who recently had surgery is bleeding. What blood product does the nurse anticipate administering for this client?

platelets

colloid osmotic pressure

pressure exerted by plasma proteins on permeable membranes in the body

what should you do if peripheral venous access site leaks fluid when flushed

remove it from site; restart IV in another site

A client's blood pressure has dropped from 146/92 mmHg to 107/68 mmHg over the course of several minutes. Increased levels of which of the following will be released into the client's bloodstream?

renin

respiratory acidosis and alkalosis

respiratory acidosis: excess of carbonic acid in ECF respiratory alkalosis: deficit of carbonic acid in ECF

Calcium and Vitamin D

similar relationship; high Ca = high Vit D

magnesium and calcium

similar relationship; low Mg = low Ca

magnesium and potassium

similar relationship; low Mg = low K

electrolytes

substance capable of breaking into ions and developing an electric charge when dissolved in solution; measured in mEq

acid

substance containing hydrogen ion that can be released

solutes

substance dissolved in a solution (electrolytes and nonelectrolytes)

base

substance that can trap a hydrogen ion

buffer

substance that prevents body fluid from becoming overly acid or alkaline

osmosis

water (solvent) passes from area of lesser concentration to an area of greater concentration until equilibrium is established -major method of transporting body fluids

autologous transfusion

when a pt donates ones own blood for a transfusion