IB Fluids, Electrolytes, and Acid-Base Balance Lecture Notes PDF

FLUIDS ELECTROLYTES ACID-BASE BALANCE Inge Luce, MSN/Ed, RN-C, NRP  FLUIDS Fluid Distribution Water with dissolved or suspended substances Intracellular (in the cells) (glucose, protein, ions,...

FLUIDS ELECTROLYTES ACID-BASE BALANCE Inge Luce, MSN/Ed, RN-C, NRP  FLUIDS Fluid Distribution Water with dissolved or suspended substances Intracellular (in the cells) (glucose, protein, ions, cells) 65% Electrolyte Extracellular (outside of cells) Mineral salt that dissolves in water and separates into ions 35% Ion (charged particle) 25% Interstitial (between cells) Cation + 8% Intravascular (in blood Sodium, potassium, calcium magnesium vessels) Anion – 2% Transcellular (in small fluid Chloride, bicarbonate, phosphate pockets)  HOMEOSTASIS IONS MOVE WATER MOVES Diffusion Osmosis High to low Low to high Ion channels are open Ion channels are closed Equalizes concentration Active TransPort Filtration Uses ATP High to low Moves low to high to create pressure Edema results Uses pressure from an error in gradient Hydrostatic pushes filtration Colloid pulls  FACTORS OF INTAKE AND OUTPUT Fluid intake and Fluid distribution Fluid output absorption PO intake: Filtration between Sensible: fluid/food, G-Tube spaces (kidneys, kidneys/urine, Thirst is triggered vascular/interstitial diarrhea, emesis by hypovolemia, ) Insensible: increased blood Osmosis between lungs, skin osmolality, or cells decreased blood volume  Clients at risk for FV Imbalance: FLUID BALANCE Age, Medical Hx, Environment, Diet, Nutrition, Medications S/S Fluid volume overload S/S Fluid volume deficit WEIGHT GAIN WEIGHT LOSS HYPERTENSION HYPOTENSION (ORTHOSTATIC first) TACHYCARDIA, BOUNDING PULSE TACHYCARDIA CRACKLES, DYSPNEA, ORTHOPNEA TACHYPNEA PITTING EDEMA POOR/TENTING TURGOR, DRY CRACKED JUGULAR VEIN DISTENSION MUCUS MEMBRANES SCANT, DARK URINE (Oliguria)  FLUID BALANCE IN CHILDREN Causes Notes Output is greater than Intake Infants and children have a greater risk of dehydration than an adult Gastroenteritis: Diarrhea, Vomiting Fluid and electrolyte imbalances occur NPO status more frequently and rapidly in pediatric patients Fever, Sweating, Infections Infants and young children do not compensate well for fluid losses Medications, Diuretics In infants, 66% of their insensible losses Trauma, Burns are through the skin, which increases with a fever Diabetic ketoacidosis They lose 7ml/kg every 24 hours for each degree above 99  S/S OF DEHYDRATION IN CHILDREN Mild Moderate Severe Normal appearance, Tacky mucosa, Decreased Dry, cracked mucosa, Absent Increased thirst, tears, Decreased UOP tears, Oliguria or anuria Decreased UOP Increased thirst, slightly Intense thirst, Sunken orbits sunken orbits (flat fontanel (fontanels), Tenting turgor until closure) Tachycardia (>160), Lethargy, Tenting (poor) Tachypnea, Hypotension turgor (under 70) Tachycardia, Tachypnea, Cool and mottled skin TENTING (POOR) TURGOR  Maintain fluid and electrolyte balance Potassium only once urine output is adequate Replace volume deficits Oral rehydration is preferred for alert children who can swallow F LU I D R E S U S C I TAT I O N Goal is 10 ml/kg/hour plus losses from IN CHILDREN previous hour Parenteral routes for moderate to severe dehydration 20 ml/kg fluid boluses Use infusion pumps for accurate I&O Treat the underlying cause  The elderly are at greater risk of fluid volume deficit because: They have a lower percentage of body water normally They have decreased thirst mechanism FLUID They may have difficulty obtaining fluids if they BALANCE IN have impaired mobility Or may avoid drinking adequate fluids if they THE ELDERLY have an issue with elimination They may be taking medications that increase fluid excretion  ELECTROLYTES Know normal ranges and the terms Causes for highs and lows Signs and symptoms of highs and lows  ELECTROLYTES Electrolyte Normal Range Notes SODIUM 135-145 mEq/L PRIMARY EXTRACELLULAR CATION POTASSIUM 3.5-5 mEq/L PRIMARY INTRACELLULAR CATION CALCIUM 8.4-10.5 mg/dl Inverse relationship with PHO4--- MAGNESIUM 1.5-2.5 mEq/L CHLORIDE 95-105 mEq/L PRIMARY EXTRACELLUAR ANION BICARBONATE 22-26 ARTERIAL (24-30 VENOUS) PHOSPHATE 2.7-4.5 mg/dL Inverse relationship with Ca++  SODIUM 136-145 MEQ/L Hyponatremia < 136 Hypernatremia > 145 CAUSES: CAUSES: Increased water or loss of salt Decreased water or excess sodium Fluid volume overload, liver disease, adrenal Dehydration, kidney disease, insufficiency hypercortisolism S/S: S/S: Osmolality decreases Osmolality increases Lethargy, headache, confusion Fever, restless, hypertension, edema, dry mouth CRITICAL: CRITICAL: Altered mental status : seizures : safety Altered mental state : seizures : safety Respiratory depression, failure, or arrest  POTASSIUM 3.5-5 MEQ/L Hypokalemia < 3.5 Hyperkalemia > 5 CAUSES: CAUSES: GI losses: diarrhea, vomiting, suction (or poor Increased PO/IV potassium, cellular damage, kidney intake) failure Excess insulin, alkalosis, fluid volume overload Lack of insulin, acidosis, dehydration, adrenal insufficiency Potassium wasting diuretics (Lasix) Potassium sparing diuretics (Spironolactone) S/S; S/S: Muscle weakness, constipation, cardiac Muscle weakness, diarrhea, cardiac dysrhythmias dysrhythmias CRITICAL: CRITICAL: Cardiac monitor: dysrhythmias, hypotension, arrest Respiratory failure, arrest Bradycardia, tall, peaked T waves, wide QRS Cardiac monitor: dysrhythmias, arrest  CALCIUM 9-10.5 MG/DL Hypocalcemia < 9 Hypercalcemia >10.5 CAUSES: CAUSES: Nutrition deficiency, vit d deficiency, kidney failure, Prolonged immobilization, bone tumors chronic diarrhea, trauma/hemorrhage Alkalosis (causes Ca to bind to albumin – reversible) HypERparathyroid HypOparathyroid Thiazide diuretics Blood transfusions, laxatives S/S: S/S: Anorexia, n/v, constipation, loss of reflexes, Numbness, tingling, hyperreflexive muscles, Chvostek, Trousseau, tetany lethargy CRITICAL: CRITICAL: Cardiac monitor, bleeding Cardiac monitor, cardiac arrest  PHOSPHATE 3.0 - 4.5 MG/DL Hypophosphatemia < 3 Hyperphosphatemia >4.5 CAUSES: CAUSES: Malnutrition Kidney failure, DKA, rhabdomyolysis HypERcalcemia HypOcalcemia HypERparathyroid HypOparathroid Excessive antacid use. S/S: S/S: Typically asymptomatic Lethargy, weakness, anorexia, nausea May develop s/s of hypocalcemia Same as hypercalcemia  MAGNESIUM 1.8-2.6 MEQ/L Hypomagnesemia < 1.8 Hypermagnesemia > 2.6 CAUSES: CAUSES: End-stage Renal Disease (ESRD) Malnutrition, chronic alcoholism, chronic diarrhea, Will need dialysis as treatment for ESRD Magnesium based Laxatives and Antacids Laxative use, thiazide diuretics S/S: S/S: LETHARGY, LOSS OF REFLEXES, Chvostek and trousseau +, hyperactive DYSRHYTHMIAS, CARDIAC ARREST reflexes, muscle cramping CRITICAL: CRITICAL: Cardiac monitor, Cardiac Arrest Seizures and Safety Respiratory depression (diaphragm cannot contract)  ACID-BASE BALANCE Know normal values for pH, CO2, HCO3- Identify causes of acid-base imbalances Interpret blood gasses  ACID-BASE BALANCE pH is the “potential to accept more hydrogen” The higher the pH, the more acid the fluid could accept High pH = alkalosis (base) The lower the pH, the less acid the fluid could accept (the more acid it already has) Low pH = acidosis There are 2 main types of acids in the body Carbonic acid (H2CO3), broken down into CO2, is expelled during exhalation Metabolic acids= lactic and citric acids created as byproducts of metabolism, expelled through kidneys (hydrogen excretion) THE BICARBONATE BUFFER SYSTEM  ACID BASE BALANCE Management of acidosis Blood buffers act immediately to bind to hydrogen Bicarbonate (ECF), Phosphate (ICF), and hemoglobin and plasma proteins (blood) Respiration Regulation of carbon dioxide levels In response to increased CO2 (increased H+ ions) Rate increases to exhale more CO2 Quick but cannot maintain for a long period of time Kidneys movement of bicarbonate (retention) and hydrogen (excretion) More effective but take 24 to 48 hours to work  HCO3- pH level CO2 (amount of buffer (acid-alkaline) (amount of H+) available) Normal 7.35-7.45 35-45 mmHg 22-26 mEq/L Respiratory Acidosis ↓ 7.35 ↑ 45 Respiratory Alkalosis ↑ 7.45 ↓ 35 Metabolic Acidosis ↓ 7.35 ↓ 22 Metabolic Alkalosis ↑ 7.45 ↑ 26 ACID-BASE BALANCE RO - ME  ACIDOSIS METABOLIC RESPIRATORY Diabetic Ketoacidosis (DKA) Hypoventilation Starvation Head injury Diarrhea Stroke Excessive muscle use Overdose Anesthesia Acid ingestion Airway obstruction Kidney failure Respiratory muscle dysfunction Pancreatitis, liver failure PE, COPD  ALKALOSIS METABOLIC RESPIRATORY Antacid overuse Hyperventilation Blood transfusion Fear, anxiety TPN Mechanical ventilation (too fast/deep) Prolonged vomiting Aspirin overdose NG tube suction Early-stage acute respiratory Diuretics (loop and thiazide) problems Increased cortisol or aldosterone  PRACTICE 19-year-old male brought into the ED with a femur fracture. VS: 98.7, 110, 24, 117/63, 97% RA He is very anxious and complains of tingling around his mouth and fingers ABG: pH 7.48 CO2 32 HCO3- 24  PRACTICE 76-year-old with end-stage emphysema is brought to the ED by EMS with respiratory failure. VS: 99.4, 142 irregular, 44 shallow, 90/40, 80% with assisted ventilations (BVM) He is cyanotic, eye lids are drooping, does not follow objects, moans to painful stimulation. ABG: pH 7.30 PaO2 40% PaCO2 85 HCO3- 40  PRACTICE 40-year-old woman with diabetes has been admitted for a skin wound. VS: 101.9, 124, 22, 140/86, 94% RA She is complaining of severe thirst and frequent urination ABG: pH 7.28 CO2 30 HCO3- 18  PRACTICE 3-year-old with severe dehydration after 24 hours of recurrent vomiting from gastroenteritis. VS: 101.9, 140, 26, 76/40, 92% RA Lethargic, sunken eyes, tenting skin turgor, scant, dark, urine ABG: pH 7.46 CO2 36 HCO3- 30