Fluids Class - Fluids and Electrolytes

Fluids and Electrolytes Chapter 45 Objectives  Review of fluid dynamics  Recognize the different forms of fluid replacement  Identify conditions for which of the fluid therapies is used  Discuss body potassium and sodium imbalances and treatments to correct conditions  Identify imp...

Fluids and Electrolytes Chapter 45 Objectives  Review of fluid dynamics  Recognize the different forms of fluid replacement  Identify conditions for which of the fluid therapies is used  Discuss body potassium and sodium imbalances and treatments to correct conditions  Identify implications for care of clients receiving fluid and electrolyte therapies Fluid Balance Total body water (TBW) 60% of adult human body is water Three main compartments of TBW Intracellular fluid (ICF) 67% Interstitial fluid (IF) 25% Plasma volume (PV) 8% 33% = ECF Fluids Components of ECF Interstitial fluid Blood (plasma + cells)  Blood constituents  plasma proteins  RBCs  platelets  WBCs Fluid Balance Distribution of fluid in ECF determined by bulk flow Starling forces  Blood Pressure Plasma Proteins Balance of 2 main pressures Hydrostatic pressure (blood pressure) Colloid osmotic pressure due to plasma proteins Fluid Balance Water Balance Water Intake = Water Loss When balance goes wrong… Fluid (Out of) Balance Edema Dehydration and fluid loss IV Fluid Administration Dehydration Electrolyte imbalances Blood component deficiencies Nutrition IV Fluids Crystalloids Colloids Blood + Blood Products Crystalloids Fluids and Electrolytes: Crystalloids Contain water plus: electrolytes (eg Na+, K+, Cl-) small molecules (eg glucose, lactate) Do NOT contain proteins/large molecules (colloids) Crystalloids Solutions of electrolytes and other small molecules  Osmolarity (mOsm/L) Solution Na Cl K Normal saline 154 154 HYPERtonic Saline 513 513 Lactated Ringer (LR) 130 109 4 D5W 0 0 1 Fluids and Electrolytes: Crystalloids Normal saline (0.9% sodium chloride) Half normal saline (0.45% sodium chloride) Hypertonic saline (3% sodium chloride) Lactated Ringer’s D5W Normosol/Plasmalyte Fluids and Electrolytes: Crystalloids To treat dehydration Volume loss or maintenance Used as replacement/maintenance fluids Compensate for insensible fluid losses (eg NS) To replace fluids (eg NS) To manage specific fluid and electrolyte disturbances (eg Ringer’s lactate) Promote urinary flow (eg NS) Expand plasma volume (eg 3% NaCl) Crystalloids: Indications Indications include: Acute liver failure Acute nephrosis Burns Hypovolemic shock Renal dialysis Many other conditions Fluids and Electrolytes: Crystalloids NS (0.9% NaCl) NS-based fluids used with administration of blood cell products Crystalloids: Adverse Effects Edema - peripheral or pulmonary Fluid overload May dilute plasma proteins Effects may be short-lived Many other effects Colloids Fluids and Electrolytes: Colloids Increase COP (colloid osmotic pressure) Move fluid from interstitial compartment to plasma compartment “plasma volume expanders”  restore BP initiate diuresis eg removal ascites in patients with portal hypertension Fluids and Electrolytes: Colloids Dextran 40 or 70 (BIG glucose polymers) Hetastarch / hydroxyethyl starch (HES) synthetic, derived from cornstarch Modified gelatin albumin (from human donors) Colloids: Indications Indications include: Trauma Burns Sepsis Hypovolaemic shock Plasma Volume Expansion Colloid vs crystalloids Colloids versus crystalloids for fluid resuscitation in critically ill patients  Perel P, Roberts I, Ker K. Cochrane Database of Systematic Reviews 2013, Issue 2. Art. No.: CD000567. DOI: 10.1002/14651858.CD000567.pub6.  “There is no evidence from randomised controlled trials that resuscitation with colloids reduces the risk of death, compared to resuscitation with crystalloids, in patients with trauma, burns or following surgery” Colloids: Indications Superior to crystalloids in plasma volume expansion? colloids more expensive Colloids: Adverse effects Usually safe concerns in renal failure Disadvantages may cause altered coagulation  bleeding no oxygen-carrying capacity  Blood & Blood Products https://professionaleducation.blood.ca/en/transfusion/clinical-guide/blood-components Fluids and Electrolytes: Blood & Blood Products Most expensive and least available fluid because they require human donors Fluids and Electrolytes: Blood & Blood Products Whole blood RBC products carry oxygen Increase supply of various products eg clotting factors from plasma Platelets Blood Products: Indications Packed RBCs and whole blood To increase oxygen-carrying capacity anemia substantial hemoglobin deficits blood loss >25% of total blood volume Blood Products: Indications Fresh frozen plasma (FFP) Increase clotting factor levels in clients with demonstrated deficiency = coagulation disorder  eg disseminated intravascular coagulation (DIC) Cryoprecipitate and plasma protein factors (PPF) eg fibrinogen, Factor VIII, prothrombin complex concentrates Blood Products: Adverse effects Transfusion reaction Blood type and cross-match Transmission of pathogens to recipient (hepatitis B & C, HIV) Client Care Administer colloids slowly Monitor for fluid overload and possible heart failure Monitor closely for signs of transfusion reactions  Advantages Disadvantages Crystalloids Few side-effects Short duration of Low cost action Wide availability May cause edema Colloids Longer duration of action Higher cost May cause volume Less fluid required to overload correct hypovolaemia May interfere with clotting Risk of anaphylactic reactions  Plasma Electrolytes Electrolytes Principal ECF electrolytes Sodium (NA+) Chloride (Cl-) Principal ICF electrolyte Potassium (K+) Others Calcium, magnesium, phosphorus Plasma Potassium Electrolytes: Potassium Potassium is responsible for: Skeletal muscle contraction Transmission of nerve impulses Regulation of heartbeat Maintenance of acid-base balance Many other functions Electrolytes: Potassium Most abundant positively charged electrolyte inside cells 95% of body’s potassium is intracellular Normal ECF - 3.5 to 5 mmol/L Potassium levels are critical to normal body function Electrolytes: Potassium Potassium obtained from foods Fruit, fish, vegetables, poultry, meats, dairy products Excess dietary potassium excreted via kidneys Impaired kidney function leads to higher serum levels, possibly toxicity Electrolytes: Potassium Hypokalemia: deficiency of potassium 5 mmol/L Many causes FYI  Potassium supplements  Burns  ACE inhibitors  Trauma  Renal failure  Metabolic acidosis  Excessive loss from cells  Addison’s Disease  Potassium-sparing (hypoaldosteronism) diuretics Potassium Treatment Hyperkalemia Cardiac rhythm irregularities  leading to possible ventricular fibrillation and cardiac arrest Muscle weakness, paralysis Paresthesia (tingling) Treatment  IV sodium bicarbonate, calcium salts, dextrose with insulin  Sodium polystyrene sulfonate (Kayexalate) or hemodialysis to remove excess potassium Client Care Parenteral infusions of potassium must be monitored closely  Rate should not exceed 10 mmol/hour NEVER give as an IV bolus or undiluted Oral forms of potassium  must be diluted in water or fruit juice to minimize GI distress or irritation  monitor for complaints of nausea, vomiting, GI pain, or GI bleeding Plasma Sodium Electrolytes: Sodium Most abundant positively charged electrolyte outside cells Normal concentration outside cells is 135 to 145 mmol/L Dietary intake of sodium chloride Salt, fish, meats, foods flavoured or preserved with salt Electrolytes: Sodium Sodium is responsible for: Control of water distribution Fluid and electrolyte balance Osmotic pressure of body fluids Participates in acid-base balance Electrolytes: Sodium Hyponatremia sodium loss or deficiency serum levels 145 mmol/L Symptoms edema, hypertension red, flushed skin; dry, sticky mucous membranes, increased thirst, elevated temperature, decreased urine output Electrolytes: Sodium  Hypernatremia Causes kidney malfunction inadequate water consumption and dehydration What fluids to give? Sodium: Indications Treatment or prevention of sodium depletion when dietary measures are inadequate Mild Treated with oral sodium chloride and/or fluid restriction Severe IV normal saline or lactated Ringer’s solution Sodium: adverse effects Oral administration Nausea, vomiting, cramps IV administration Venous phlebitis Client Care Monitor serum electrolyte levels during therapy Monitor infusion rate, appearance of fluid or solution, infusion site Observe for infiltration, other complications of IV therapy Nursing Monitor for therapeutic response Normal lab values RBCs, WBC, Hgb and Hct, electrolyte levels Improved fluid volume status Increased tolerance to activities Monitor for adverse effects