Copyright © 2016, 2013, 2010, 2006, 2002 by Saunders, an imprint of Elsevier Inc. CHAPTER 11 IGGY-PG Assessment and Care of Patients with Fluid and Electrolyte Imbalances

Copyright © 2016, 2013, 2010, 2006, 2002 by Saunders, an imprint of Elsevier Inc. OBJECTIVES  Describe basic concepts of fluid and electrolyte balance  Define ways fluids and electrolytes maintain homeostasis  Identify nursing interventions to promote fluid, electrolyte balance and how to correct.  Describe pathophysiology of selected fluid and electrolyte imbalances  Identify key electrolytes and their normal lab values  Identify considerations related to the older adult 2

Copyright © 2016, 2013, 2010, 2006, 2002 by Saunders, an imprint of Elsevier Inc. HOMEOSTASIS  Proper functioning of all body systems; requires fluid and electrolyte balance  Extracellular fluid (ECF)  Intracellular fluid (ICF)  Interstitial fluid  Transcellular fluids 3

Copyright © 2016, 2013, 2010, 2006, 2002 by Saunders, an imprint of Elsevier Inc. FILTRATION  Movement of fluid through cell or blood vessel membrane because of differences in water pressure (hydrostatic pressure)  This is related to water volume pressing against confining walls 4

Copyright © 2016, 2013, 2010, 2006, 2002 by Saunders, an imprint of Elsevier Inc. HYDROSTATIC PRESSURE  “ Water-pushing pressure”  Force that pushes water outward from a confined space through a membrane  Amount of water in any body fluid space determines pressure  Example: Blood pressure  Moving whole blood from the heart to capillaries where filtration occurs to exchange water, nutrients, and waste products between the blood and tissues 5

Copyright © 2016, 2013, 2010, 2006, 2002 by Saunders, an imprint of Elsevier Inc. CLINICAL SIGNIFICANCE: EDEMA  Develops with changes in normal hydrostatic pressure differences 6

Copyright © 2016, 2013, 2010, 2006, 2002 by Saunders, an imprint of Elsevier Inc. DIFFUSION  Free movement of particles (solute) across permeable membrane from area of higher to lower concentration  Important in transport of most electrolytes; other particles diffuse through cell membranes  Sodium pumps  Glucose cannot enter most cell membranes without help of insulin 7

Copyright © 2016, 2013, 2010, 2006, 2002 by Saunders, an imprint of Elsevier Inc. OSMOSIS & FILTRATION  Act together at capillary membrane to maintain normal ECF and ICF volumes  Thirst mechanism is example of how osmosis helps maintain homeostasis  Feeling of thirst caused by activation of brain cells responding to changes in ECF osmolarity 8

Copyright © 2016, 2013, 2010, 2006, 2002 by Saunders, an imprint of Elsevier Inc. FLUID BALANCE  Closely linked to/affected by electrolyte concentrations  Fluid intake  Fluid loss  Minimum urine amount needed to excrete toxic waste products = 400 to 600 mL/day  Insensible water loss – Through skin, lungs, stool 9

Copyright © 2016, 2013, 2010, 2006, 2002 by Saunders, an imprint of Elsevier Inc. HORMONAL REGULATION OF FLUID BALANCE  Aldosterone  Antidiuretic hormone  Natriuretic peptides and-medicine/circulatory- system/blood_pressure_control/v/aldosterone- raises-blood-pressure-and-lowers-potassium 10

Copyright © 2016, 2013, 2010, 2006, 2002 by Saunders, an imprint of Elsevier Inc. SIGNIFICANCE OF FLUID BALANCE: RENIN-ANGIOTENSIN II PATHWAY  Blood (plasma) volume and intracellular fluid most important to keep in balance  Kidneys are major regulator of water and sodium balance; maintain blood and perfusion pressure to all tissues/organs  When the kidneys sense a low parameter, they secrete renin  Renin-angiotensin II pathway is greatly stimulated with shock, or when stress response is stimulated 11

Copyright © 2016, 2013, 2010, 2006, 2002 by Saunders, an imprint of Elsevier Inc. ACE INHIBITORS  Disrupt renin-angiotensin II pathway by reducing amount of ACE produced  With less angiotensin II, less vasoconstriction and reduced peripheral resistance  Greater excretion of water and sodium in urine  By locking angiotensin II receptors, blood pressure lowers  Patients with hypertension often take ACE- inhibitor medications 12

Copyright © 2016, 2013, 2010, 2006, 2002 by Saunders, an imprint of Elsevier Inc. DEHYDRATION: COLLABORATIVE CARE  Fluid intake/retention does not meet body’s fluid needs; results in fluid volume deficit  Assessment  History  Physical assessment/clinical manifestations:  Cardiovascular  Respiratory  Skin  Neurologic  Renal 13

Copyright © 2016, 2013, 2010, 2006, 2002 by Saunders, an imprint of Elsevier Inc. FACTS TO REMEMBER...  1 L of water weighs 2.2 lb, equal to 1 kg  Weight change of 1 lb = fluid volume change of about 500 mL 14

Copyright © 2016, 2013, 2010, 2006, 2002 by Saunders, an imprint of Elsevier Inc. FLUID OVERLOAD: COLLABORATIVE CARE  Assessment  Patient safety  Pulmonary edema  Drug therapy  Nutrition therapy  Monitoring of intake and output (I&O) 15

Copyright © 2016, 2013, 2010, 2006, 2002 by Saunders, an imprint of Elsevier Inc. ELECTROLYTE IMBALANCE  Can occur in healthy people as result of changes in fluid I&O  Can be life threatening if severe; can occur in any setting 16

Copyright © 2016, 2013, 2010, 2006, 2002 by Saunders, an imprint of Elsevier Inc. SODIUM  Normal level: mmol/L  “Where sodium goes, water follows”  Hyponatremia  Hypernatremia 17

Copyright © 2016, 2013, 2010, 2006, 2002 by Saunders, an imprint of Elsevier Inc. POTASSIUM  Normal level: mEq/L  Some control over intracellular osmolarity and volume  Hypokalemia  Hyperkalemia 18

Copyright © 2016, 2013, 2010, 2006, 2002 by Saunders, an imprint of Elsevier Inc. CALCIUM  Normal level: mg/dL  Absorption requires active form of vitamin D  Stored in bones  Parathyroid hormone  Thyrocalcitonin  Hypocalcemia  Hypercalcemia 19

Copyright © 2016, 2013, 2010, 2006, 2002 by Saunders, an imprint of Elsevier Inc. HYPOCALCEMIA 20

Copyright © 2016, 2013, 2010, 2006, 2002 by Saunders, an imprint of Elsevier Inc. PHOSPHORUS  Normal level: mg/dL  Found in bones  Activates vitamins and enzymes; assists in cell growth and metabolism  Plasma levels of calcium and phosphorus exist in a balanced reciprocal relationship  Hypophosphatemia  Hyperphosphatemia 21

Copyright © 2016, 2013, 2010, 2006, 2002 by Saunders, an imprint of Elsevier Inc. MAGNESIUM  Normal level: 1.3 to 2.1 mg/dL  Critical for skeletal muscle contraction, carbohydrate metabolism, ATP formation, vitamin activation, cell growth  Hypomagnesemia  Hypermagnesemia 22

Copyright © 2016, 2013, 2010, 2006, 2002 by Saunders, an imprint of Elsevier Inc. CHLORIDE  Normal level: 98 to 106 mEq/L  Imbalance occurs as a result of other electrolyte imbalances  Treat underlying electrolyte imbalance or acid- base problem 23

Copyright © 2016, 2013, 2010, 2006, 2002 by Saunders, an imprint of Elsevier Inc. CONSIDERATIONS FOR OLDER ADULTS  At risk for most electrolyte imbalances from age- related organ changes  Have less total body water than younger adults; more at risk for fluid imbalances; more likely to be taking drugs affecting fluid or electrolyte balance Extra help/resource:  electrolyte-flash-cards electrolyte-flash-cards 24