Fluids & Electrolytes PDF

FLUID AND ELECTROLYTE IMBALANCE Dr. Abdulaziz A. Al-Mulhem Assistant Professor & Consultant General Surgery Shaqra University FLUID AND ELECTROLYTE B ALANCE IS AN EXTREMELY COMPLIC ATED THING. Electrolyte : It is a substance containing free ions that behaves as...

FLUID AND ELECTROLYTE IMBALANCE Dr. Abdulaziz A. Al-Mulhem Assistant Professor & Consultant General Surgery Shaqra University FLUID AND ELECTROLYTE B ALANCE IS AN EXTREMELY COMPLIC ATED THING. Electrolyte : It is a substance containing free ions that behaves as an electrically conductive medium… Osmosis : Net movement of the solvent across the semi permeable membrane from a region of high solute potential to an area of low solute potential. Movement of body fluids - Diffusion - Osmosis - Active transport  FLUID AND ELECTROLYTE DISTURBANCE Amount and Composition of Body Fluids: - Approximately 60% of atypical adult’s weight consists of fluid (water&electrolyte). - Body fluid is located in tow fluid compartment: 1) Intracellular fluids (fluids in the cells) 2/3. 2) Extracelluler fluids :( fluids out side the cells) 1/3. a-Intravascular space (fluids with in blood vessels) contains plasma.(3L of the total blood). b- Interstitial fluids: contain fluids that surround the cell and total about 8L.eg. Lymph. c- Trancellular space: contain approximately 1L. eg. Cerebrospinal, Pericardial, Synovial. Distribution of body fluids  AVERAGE DAILY INTAKE AND OUTPUT IN AN ADULT: Intake Output Oral Liquids 1300ml. Urine 1500ml Water in foods 1000ml. Stool 200ml Water produced Insensible lungs 300ml by metabolism 300ml Skin 600ml 2600ml 2600ml  NORMAL LAB RESULTS: - Na→ 135−145mEq/L. - K+ → 3.5−5.5mEq/L. - Ca++→ 8.5−10.5mEq/L. - Cl → 96−106mEq/L. - Mg→ 1.5−2.5mEq/L.  IMPORTANCE Need to make a decision regarding fluids in pretty much every hospitalized patient. Can be life-saving in certain conditions loss of body water, whether acute or chronic, can cause a range of problems from mild lightheadedness to convulsions, coma, and in some cases, death. Though fluid therapy can be a lifesaver, it's never innocuous, and can be very harmful.  KINDS OF IV FLUID SOLUTIONS Hypotonic - 1/2NS Isotonic - NS, LR, albumen Hypertonic - Hypertonic saline. Crystalloid Colloid  CRYSTALLOID VS COLLOID TYPE OF PARTICLES (LARGE OR SMALL) Fluids with small “crystalizable” particles like NaCl are called crystalloids Fluids with large particles like albumin are called colloids, these don’t (quickly) fit through vascular pores, so they stay in the circulation and much smaller amounts can be used for same volume expansion. (250ml Albumin = 4 L NS) Edema resulting from these also tends to stick around longer for same reason. Albumin can also trigger anaphylaxis.  IV MODES OF ADMINISTRATION Peripheral IV PICC Central Line Intraosseous  IV PROBLEM: EXTRAVASATION / “INFILTRATED” The most sensitive indicator of extravasated fluid or "infiltration" is to transilluminate the skin with a small penlight and look for the enhanced halo of light diffusion in the fluid filled area. Checking flow of infusion does not tell you where the fluid is going  COMPONENTS OF FLUID THERAPY There are two components to fluid therapy: Maintenance therapy replaces normal ongoing losses. Replacement therapy corrects any existing water and electrolyte deficits.  MAINTENANCE THERAPY Maintenance therapy is usually undertaken when the individual is not expected to eat or drink normally for a longer time (eg, perioperatively or on a ventilator). Big picture: Most people are “NPO” for 12 hours each day. Patients who won’t eat for one to two weeks should be considered for parenteral or enteral nutrition. Maintenance Requirements can be broken into water and electrolyte requirements:  WATER — Two liters of water per day are generally sufficient for adults; Most of this minimum intake is usually derived from the water content of food and the water of oxidation, therefore it has been estimated that only 500ml of water needs be imbibed given normal diet and no increased losses. These sources of water are markedly reduced in patients who are not eating and so must be replaced by maintenance fluids.  water requirements increase with: fever, sweating, burns, tachypnea, surgical drains, polyuria, or ongoing significant gastrointestinal losses. For example, water requirements increase by 100 to 150 mL/day for each C degree of body temperature elevation.  S E V E R A L F O R M U L A S C A N B E U S E D TO C A L C U L AT E M A I N T E NA NC E F L U I D R AT E S.  4/2/1 RULE A.K.A WEIGHT+40 I prefer the 4/2/1 rule (with a 120 mL/h limit) because it is the same as for pediatrics.  4/2/1 rule 4 ml/kg/hr for first 10 kg (=40ml/hr) then 2 ml/kg/hr for next 10 kg (=20ml/hr) then 1 ml/kg/hr for any kgs over that This always gives 60ml/hr for first 20 kg then you add 1 ml/kg/hr for each kg over 20 kg This boils down to: Weight in kg + 40 = Maintenance IV rate/hour. For any person weighing more than 20kg  WHAT TO PUT IN THE FLUIDS  START: D5 1/2NS+20 MEQ K @ WT+40/HR a reasonable approach is to start 1/2 normal saline to which 20 meq of potassium chloride is added per liter. (1/2NS+20 K @ Wt+40/hr) Glucose in the form of dextrose (D5) can be added to provide some calories while the patient is NPO. The normal kidney can maintain sodium and potassium balance over a wide range of intakes. So,start: D5 1/2NS+20 meq K at a rate equal to their weight + 40ml/hr, but no greater than 120ml/hr. then adjust as needed, see next page.  START D5 1/2NS+20 MEQ K , THEN ADJUST: If sodium falls, increase the concentration (eg, to NS) If sodium rises, decrease the concentration (eg, 1/4NS) If the plasma potassium starts to fall, add more potassium. If things are good, leave things alone.  Assessment Diagnostic evaluation Health History & Physical examination Serum BUN & Creatinine Hematocrit level “great than normal” Urine specific gravity Serum electrolytes level Hypokalemia in case of GI & renal loss Hyperkalemia in case of adrenal insufficiency Hypernatremia in case of ↑insensible losses & diabetic insipidus  FLUID VOLUME DISTURB ANCE: I-Hypovolemia (fluids volume deficit): − Contributing Factors: * Loss of water and electrolyte. e.g.( vomiting,diarrhea,burns). * Decrease intake. e.g. (anorexia, nausea, inability to gain access to fluids). * Some disease.e.g (D.M, Diabetic Insipidus). − Sings and symptoms: Weight loss, general weakness, dizziness, increase pulse.  FLUID VOLUME DISTURB ANCE: II- Hypervolemia (fluid volume excess): − Contributing Factors: * Compromised regulatory mechanism such as renal failure, congestive heart failure, and cirrhosis. * Administration of Na+ containing fluids. * Prolong corticosteroid therapy. * Increase fluid intake. − Sings and Symptoms: Weight gain, increase blood pressure, edema, and shortness of breathing.  Assessment & Diagnostic Evaluation - Decreased BUN , Creatinine , Serum osmolality & hematocrit because of plasma dilution, &↓protein intake - Urine sodium is increased if kidneys excrete excess fluid - CXR may disclosed pulmonary congestion  Management Direct cause should be treated Symptomatic treatment consist of : - Diuretics - restrict fluid & Na intake - Maintained electrolytes balance - Hemodialysis in case of renal impairment - K+ supplement & specific nutrition Nursing Management: - Assess breathing , weight ,degree of edema regularly - I & O measurement regularly - Semifowlers position in case of shortness of breath - Patient education  ELECTROLYTE IMBALANCE: I- SodiumDeficit (Hyponatremia): −Contributing Factors: * Use of a diuretic. * Loss of GI fluids. * Gain of water. − Sings and Symptoms: Anorexia, nausea and vomiting, headache, lethargy, confusion, seizures.  HYPONATREMIA, CONTINUED Treatment: correct underlying disorder Fluid restrict, + diuretics Hypertonic saline to increase level 2-3 mEq/L/hr and max rate 100cc of 5% saline/hr  ELECTROLYTE IMBALANCE: II- Sodium Excess (Hypernatremia): − Contributing Factors: * Water deprivation in patient. * Hypertonic tube feeding. * Diabetes Insipidus. − Sings and Symptoms: Thirst, hallucination, lethargy, restless, pulmonary edema.  HYPERNATREMIA, CONTINUED Treatment: correct underlying disorder Free water replacement: (0.6 * kg BW) * ((Na/140) – 1). Slow infusion of D5W give ½ over first 8 hrs then rest over next 16-24 hrs to avoid cerebral edema.  ELECTROLYTE IMBALANCE: III- Potassium Deficit (Hypokalemia): − Contributing factors: * Dirrhea, vomiting, gastric suctions. * Corticosteroid administration. * Diuretics. − Sings and symptoms: Fatigue, anorexia, nausea, vomiting, muscle weakness, change in ECG. EKG: low, flat T-waves, ST depression, and U waves  HYPOKALEMIA, CONTINUED ECG changes in hypokalemia  HYPOKALEMIA, CONTINUED ECG changes in hypokalemia  HYPOKALEMIA, CONTINUED Treatment: Check renal function Treat alkalosis, decrease sodium intake PO with 20-40 mEq doses IV: peripheral 7.5 mEq/hr, central 20 mEq/hr and increase K+ in maintenance fluids.  ELECTROLYTE IMBALANCE: IV- Potassium Excess (Hyperkalemia): − Contributing Factors: * Renal Failure. * Crush injury, burns. * Blood transfusion. * Administration of IV K+. − Sings and Symptoms: Bradycardia, dysarrythmia, anxiety, irritable. - ECG: peaked T waves then flat P waves, depressed ST segment, widened QRS progressing to sine wave and V fib. HYPERKALEMIA – ECG CHANGES HYPERKALEMIA – ECG CHANGES  HYPERKALEMIA, CONTINUED Treatment: Remove iatrogenic causes Acute: if > 7.5 mEq/L or EKG changes Ca-gluconate – 1 gm over 2 min IV Sodium bicarbonate – 1 amp, may repeat in 15min D50W (1 ampule = 50 gm) and 10U regular insulin Emergent dialysis Hydration and diuresis, kayexalate 20-50 g, in 100-200cc of 20% sorbitol q 4hrs or enema  C ALCIUM Hypocalcemia: Seen in hypoalbuminemia. Check ionized Ca Often symptomatic below 8 mEq/dL Check PTH: low may be Mg deficiency High think pancreatitis, hyperPO4, low Vitamin D, pseudohypoparathyroidism, massive blood transfusion, drugs (e.g. gentamicin) renal insufficiency S/Sx: numbness, tingling, circumoral paresthesia, cramps tetany, increased DTR’s, Chvostek’s sign, Trousseau’s sign EKG has prolonged QT interval E C G C HA N G E S I N C A L C I U M A B N O R M ALI T IE S  C ALCIUM, CONTINUED Hypocalcemia cont. Treatment: Acute: (IV) CaCl 10 cc of 10% solution = 6.5 mmole Ca or CaGluconate 10cc of 10% solution = 2.2 mmole Ca Chronic: (PO) 0.5-1.25 gm CaCO3 = 200-500 mg Ca. Phosphate binding antacids improve GI absorption of Ca Vit D (calciferol) must have normal serum PO4. Start 50,000 – 200,000 units/day  C ALCIUM, CONTINUED Hypercalcemia Usually secondary to hyperparathyroidism or malignancy. Other causes are thiazides, milk-alkali syndrome, granulomatous disease, acute adrenal insufficiency Acute crisis is serum Ca> 12mg/dL. Critical at 16-20mg/dL S/Sx: N/V, anorexia, abdominal pain, confusion, lethargy MS changes= “Bones, stone, abdominal groans and psychic overtones.”  C ALCIUM, CONTINUED Treatment: Hydration with NS then loop diuretic. Steroids for lymphoma, multiple myeloma, adrenal insufficiency, bone mets,Vit D intoxication. May need Hemodialysis. Mithramycin for malignancy induced hyperCa refractory to other treatment. Give 15-25 mcg/kg IVP Calcitonin in malignant PTH syndromes  MAGNESIUM Hypomagnesemia Malnutrition, burns, pancreatitis, SIADH, parathyroidectomy, primary hyperaldosteronism S/Sx: weakness, fatigue, MS changes, hyperreflexia, seizure, arrhythmia Treatment: IV replacement of 2-4 gm of MgSO4 per day or oral replacement MAGNESIUM  MAGNESIUM, CONTINUED Hypermagnesemia Renal insufficiency, antacid abuse, adrenal insufficiency, hypothyroidism, iatrogenic S/Sx: N/V, weakness, MS changes, hyporeflexia, paralysis of voluntary muscles, EKG has AV block and prolonged QT interval. Treatment: Discontinue source, IV CaGluconate for acute Rx, Dialysis  PHOSPHATE Treatment: PO replacement (Neutraphos) or IV KPhos or NaPhos 0.08-0.20 mM/kg over 6 hrs Hyperphosphatemia Renal insufficiency, hypoparathyroidism, may produce metastatic calcification Treat with restriction and phosphate-binding antacid (Amphogel)  ACID−B ASE DISTURB ANCE: Normal Values: PH→ 7.35- 7.45. PCO2→ 35-45mmHg. PO2→ 80-100mmHg. HCO3→ 22-26mEq/L. Respiratory Acidosis: → → → → ↑ PCO2. Respiratory Alkalosis: → → → → ↓ PCO2. Metabolic Acidosis: → → → → ↓ PH, ↓ HCO3. Metabolic Alkalosis: → → → → ↑ PH, ↑ HCO3.  TYPES OF IV SOLUTIONS: * Serum plasma osmalarity (280-300 m osmol). I- Isotonic Solutions: A solution with the same osmalality as serum and other body Fluids. e.g. N/S 0.9%, Ringer Lactate, D5W. II- Hypotonic Solutions: A solution with an osmolality lower than that of serum plasma. e.g. half strength saline (0.45% sodium chloride). III- Hypertonic Solution: A solution with an osmalality higher than that of serum. e.g. D/S 0.9%, D/S 0.18%, D/S 0.45%, D10W, D25W.  TYPES OF IV SOLUTIONS: *Hypotonic Solutions (0.45% saline) Decreases intravascular osmolarity. Results in intracellular expansion. Used for cellular dehydration. Complications include shock and increased ICP. Contraindications include cerebral edema, and hypotension.  TYPES OF IV SOLUTIONS: *Hypertonic Solutions (D5%.45% saline, D5% NS, D5%LR.) Increases intravascular osmolarity. Results in intracellular and interstitial dehydration. Used for intravascular expansion by shifting intracellular and interstitial fluids. Complications include circulatory overload. Contraindications include intracellular dehydration and hyperosmolar states.  TYPES OF IV SOLUTIONS: *Isotonic Solutions (NS, Lactated Ringers, D5%W.) Does not change osmolarity. Results in TBW expansion. Used to increase intravascular space. Complications include circulatory overload. Contraindications include circulatory overload and LR in alkalosis and liver disease. THANK YOU