Fluid-and-Electrolytes-Lecture.pdf

By: Evangeline T. Go  Help maintain body temperature and cell shape Help transport nutrients, gasses and wastes Fluids 60% of an adult’s body weight * 70 Kg adult male: 60% X 70= 4L More fat = ↓water More muscle = ↑water Infants and elderly - prone to fluid imba...

By: Evangeline T. Go  Help maintain body temperature and cell shape Help transport nutrients, gasses and wastes Fluids 60% of an adult’s body weight * 70 Kg adult male: 60% X 70= 4L More fat = ↓water More muscle = ↑water Infants and elderly - prone to fluid imbalance  60 % Intracellular Fluid 40% or 2/3 Extracellular Fluid 20% or 1/3 Arterial Fluid 2% Intravascular Interstitial 5% or 1/4 15% or 3/4 Venous Fluid 3% Transcellular fluid 1-2% ie csf, pericardial, synovial, intraocular, sweat Third-space fluid shift/Third “spacing” - loss of ECF into a space that does not contribute to equilibrium between ICF and ECF - ie ascites, burns, peritonitis, bowel obstruction, edema Transport Mechanisms fluids from different compartments move from one compartment to the other to maintain fluid balance. movement is dictated by the transport mechanism principle : A. PASSIVE B. ACTIVE TRANSPORT A. Passive Transport Process – substances transported across the membrane w/o energy input from the cell - high to low concentration 2 Types of Passive Transport 1. Diffusion – substances/solutes move from high concentration to low concentration ie exchange of O2 and CO2 b/w pulmonary capillaries and alveoli 2. Filtration – water and solutes forced through membrane by fluid or hydrostatic pressure from intravascular to interstitial area - solute containing fluid (filtrate) from higher pressure to lower pressure B. Active Transport Process - Cell moves substances across a membrane through ATP because: >They may be too large >Unable to dissolve in the fat core Types of Active Transport 1. Active transport – requires protein carriers using ATP to energize it ie Amino acids Sodium potassium pump – 3Na out, 2K in 2. Endocytosis – moves substances into the cell 3. Exocytosis – moves substances out of the cell Active Transport Osmosis Movement of water from low solute to high solute concentration in order to maintain balance between compartments. Osmotic pressure – amount of hydrostatic pressure needed to stop the flow of water by osmosis Oncotic pressure – osmotic pressure exerted by proteins Osmosis Osmosis Diffusion Regulation of Body Fluid 1. The Kidney Regulates primarily fluid output by urine formation 1.5L Releases RENIN Regulates sodium and water balance 2. Endocrine regulation thirst mechanism – thirst center in hypothalamus ADH increase water reabsorption on collecting duct Aldosterone increases Sodium and water retention retention in the distal nephron ANP Promotes Sodium excretion and inhibits thirst mechanism Atrial Natriuretic Peptide: Regulates Na+ & H2O Excretion  ADH Regulation ADH - produced by the Hypothalamus - stored and secreted by the posterior pituitary gland less water in plasma, ADH secreted to conserve water by reducing urine output fluid overload in plasma, ADH secretion stops to excrete fluid in the kidneys by increasing urine output  ADH Disorder Abnormally high ADH concentration - SIADH reduced urine output (oliguria) water retention (fluid overload) Abnormally low ADH – Diabetes Insipidus increased urine output (polyuria) water loss (fluid deficit) 3. Gastro-intestinal regulation - GIT digests food and absorbs water - Only about 200 ml of water is excreted in the fecal material per day 4. Heart and Blood Vessel Functions - pumping action of heart circulates blood through kidneys 5. Lungs – insensible water loss through respiration Intake and Output I and O must be equal 2.6 L per day Essential = Measurable = Sensible Non essential = estimated Measurement= Insensible  Sources of Fluids Fluid Intake 1. Exogenous sources Fluid intake 2, 600 ml oral liquids – 1, 300 ml water in food – 1, 000 ml water produced by metabolism – 300 ml IVF Medications Blood products 2. Endogenous sources By products of metabolism secretions  Fluid Output Sensible loss Urine - 1, 500 ml Fecal losses – 200 ml Insensible loss skin – 600 ml Lungs – 300 ml  I&O Imbalance Fluid Volume Deficit output, normal intake Normal output,  intake No intake or prolonged decreased intake Causes of FVD Vomiting, diarrhea, GI suctioning, sweating Diabetes Insipidus Adrenal insufficiency Osmotic diuresis Hemorrhage 3rd space fluid shift Assessment of FVD ICF cellular dehydration Acidosis ISF skin poor skin turgor IVF artery ↓BP, pulse (rapid thready) vein ↓CVP Clinical manifestations Weight loss Oliguria Concentrated urine Postural hypotension Flattened neck veins Increased Temp Dec CVP Thirst, anorexia Muscle weakness and cramps Laboratory BUN:Crea > 20:1 Inc Hct – RBC suspended in Dec plasma volume Dec K – GI and renal losses Inc K – adrenal insufficiency Dec Na – inc thirst and ADH Inc Na – insensible losses and DI Medical Management Oral intake when mild IV route, acute or severe Isotonic fluids ie LR for hypotensive patients to expand plasma volume Assess I and O, weight, CVP, LOC, breath sounds and skin color Fluid challenge test – 100-200 ml x 15 min Nursing Management Monitor and measure I and O Monitor VS closely Monitor skin turgor and tongue furrows Monitor urinary concentration Monitor mental function Fluid Volume Excess  intake, normal output Normal intake,  output No output Nursing Management Measure intake and output Weigh daily 2 lb wt gain = 1 L fluid Assess breath sounds Monitor degree of edema ie ambulatory – feet and ankles bedridden – sacral area Promote rest – favors diuresis/inc venous return Administer appropriate medication Causes of FVE Heart failure, renal failure, cirrhosis of the liver – d/t aldosterone stimulation/Congestion Increased consumption of table salt Excessive administration of Na containing fluids in a patient w/ impaired regulatory mechanism SIADH Assessment of FVE ICF cellular edema ↓LOC pulmonary edema crackles (bibasilar), wheezing, shortness of breath, Inc RR ISF skin bipedal pitting edema, periorbital edema and ANASARCA IVF artery ↑BP, pulse (rapid bounding) vein ↑CVP Clinical Manifestations Distended neck veins Tachycardia Inc weight Increased urine output Shortness of breath and wheezing/crackles Inc CVP Edema common manifestation of FVE d/t inc capillary fluid pressure, decreased capillary oncotic pressure, increased interstitial oncotic pressure Localized or generalized Etiology: obstruction to lymph flow, plasma albumin level < 1.5-2 g/dl, burns and infection, Na retention in ECF, drugs  Labs: Dec Hct, respiratory alkalosis and hypoxemia, dec serum Na and osmolality, inc BUN Crea, dec urine Na level Mgmt: diuretics, fluid restriction, elevation of extremities, elastic compression stockings, paracentesis, dialysis Laboratory Dec BUN Dec Hct CRF – serum osmolality and Na level dec Cxr – pulmonary congestion Medical Management Discontinue administration of Na solution Diuretics ie Thiazide – block Na reabsorption in distal tubule Loop diuretics – block Na reabsorption in ascending loop of Henle Restrict fluid and salt intake Dialysis Types of Fluid Tonicity - ability of solutes to cause osmotic driving forces Isotonic Fluid - no movement of fluid. Isotonic Fluids 0.9% NaCl/ Normal Saline/NSS -Na=154 -Cl=154 -308 mOsm/L - not desirable as routine maintenance solution - only solution administered with blood products Rx: hpovolemia, shock, DKA, metabolic alkalosis, hypercalcemia, mild NA deficit CI: caution in renal failure, heart failure and edema  D5W - 5% Dextrose in water - 170 cal and free water - 252 mOsm/L Rx: hypernatremia, fluid loss and dehydration Contraindication: early post op when ADH inc d/t stress, sole treatment in FVD (dilutes plasma), head injury (inc ICP), fluid resuscitation (hyperglycemia), caution in renal and cardiac dse (fluid overload), px with NA deficiency (peripheral circulatory collapse and anuria)  Lactated Ringer’s Solution isotonic - Na 130 mEq/L - K 4 mEq/L -Ca 3 mEq/L - Cl 109 mEq/L - 273 mOsm/L Rx:hypovelemia, burns, flids lost as bile/diarrhea, acute blood loss CI: ph>7.5, lactic acidosis, renal failure(cause HyperK) Hypotonic Fluid - fluid will enter the cell, the cell will swell Hypotonic Fluids 0.45% NaCl (half strength saline) - provides Na, Cl and free water - Na 77 mEq/L - Cl 77 mEq/L - 154 mOsm/L Rx: hypertonic dehydration, Na and Cl depletion, gastric fluid loss CI : 3rd space fluid shifts and inc ICP Hypertonic Fluid - fluid will go out from the cell, the cell will shrink Hypertonic Fluids 3% NaCl (hypertonic saline) - no calories - Na 513 mEq/L - Cl 513 mEq/L -1026 mOsm/L Rx: critical situations to treat HypoNa, assist in removing ICF excess CI: administered slowly and cautiously (IVF overload and pulmonary edema) 5% NaCl  D10W - 10% Dextrose in water hypertonic (505 mOsm/L) D10W - 20% Dextrose in water hypertonic (1011 mOsm/L) D50W - 50% Dextrose in water hypertonic (1700 mOsm/L) D5NS - 5% Dextrose & 0.9NaCl hypertonic (559 mOsm/L) D10NS - 10% Dextrose & 0.9NaCl hypertonic (812 mOsm/L) D5LR - 5% Dextrose in Lactated Ringers hypertonic (524 mOsm/L An average adult’s weight is 60% water. And the majority of our body’s fluid is located in what fluid compartment? A. extracellular B. intracellular C. Transcellular D. intravascular An average adult’s weight is 60% water. And the majority of our body’s fluid is located in what fluid compartment? A. extracellular B. intracellular C. Transcellular D. intravascular A type of passive transport which involves a movement of substances from a low to a high concentration is: A. diffusion B. filtration C. osmosis D. convection A type of passive transport which involves a movement of substances from a low to a high concentration is: A. diffusion B. filtration C. osmosis D. convection ELECTROLYTES elements or compounds when dissolved in water will dissociate into ions and are able to conduct an electric current. FUNCTIONS: 1. Regulate fluid balance and osmolality 2. Transmission of nerve impulse 3. Stimulation of muscle activity  ANIONS - negatively charged ions: Bicarbonate, chloride, PO4-, CHON CATIONS - positively charged ions: Sodium, Potassium, magnesium, calcium Regulation of Electrolyte Balance 1. Renal regulation Occurs by the process of glomerular filtration, tubular reabsorption and tubular secretion Urine formation  If there is little water in the body, it is conserved  If there is water excess, it will be eliminated 2. Endocrinal regulation Aldosterone promotes Sodium retention and Potassium excretion ANP promotes Sodium excretion Parathormone increased bone resorption of Ca, inc Ca reabsorption from renal tubule or GI tract Calcitoninoppose PTH Insulin and Epinephrine – promotes uptake of Potassium by cells The Cations SODIUM POTASSIUM CALCIUM MAGNESIUM SODIUM (Na) MOST ABUNDANT cation in the ECF 135-145 mEq/L Aldosterone increases sodium reabsorption ANP increases sodium excretion Cl accompanies Na FUNCTIONS: 1. assists in nerve transmission and muscle contraction 2. Major determinant of ECF osmolality 3. Primary regulator of ECF volume a. HYPERNATREMIA Na > 145 mEq/L Assoc w/ water loss or sodium gain Etiology: inadequate water intake, excessive salt ingestion /hypertonic feedings w/o water supplements, near drowning in sea water, diuretics, Diabetes mellitus/ Diabetes Insipidus S/SX: polyuria, anorexia, nausea, vomiting, thirst, dry and swollen tongue, fever, dry and flushed skin, restlessness, agitation, seizures, coma, muscle weakness, crackles, dyspnea, cardiac manifestations dependent on type of hypernatremia Dx: inc serum sodium and Cl level, inc serum osmolality, inc urine sp.gravity, inc urine osmolality Mgmt: sodium restriction, water restriction, diuretics, isotonic non saline soln. (D5W) or hypotonic soln, Desmopressin Acetate for Diabetes Insipidus Nsg considerations History – diet, medication Monitor VS, LOC, I and O, weight, lung sounds Monitor Na levels Oral care initiate gastric feedings slowly Seizure precaution b. HYPONATREMIA Na < 135 mEq/L Etiology: diuretics, excessive sweating, vomiting, diarrhea, SIADH, aldosterone deficiency, cardiac, renal, liver disease  Dx: dec serum and urine sodium and osmolality, dec Cl s/sx:headache, apprehension, restlessness, altered LOC, seizures( 5.0 mEq/L Etiology: IVF with K+, acidosis, hyper-alimentation and excess K+ replacement, decreased renal excretion, diuretics, Cancer s/sx: nerve and muscle irritability, tachycardia, colic, diarrhea, ECG changes, ventricular dysrythmia and cardiac arrest, skeletal muscle weakness, paralysis Dx: inc serum K level ECG: peaked T waves and wide QRS ABGs – metabolic acidosis Mgmt: K restriction (coffee, cocoa, tea, dried fruits, beans, whole grain breads, milk, eggs) diuretics Polystyrene Sulfonate (Kayexalate) IV insulin Beta 2 agonist IV Calcium gluconate – WOF Hypotension IV NaHCo3 – alkalinize plasma Dialysis Nsg consideration: Monitor VS, urine output, lung sounds, Crea, BUN monitor K levels and ECG observe for muscle weakness and dysrythmia, paresthesia and GI symptoms  b. HYPOKALEMIA K+ < 3.5 mEq/L Etiology: use of diuretic, corticosteroids and penicillin, vomiting and diarrhea, ileostomy, alkalosis, hyperinsulinism, hyperaldosteronism s/sx: anorexia, nausea, vomiting, decreased bowel motility, fatigue, muscle weakness, leg cramps, paresthesias, shallow respiration, shortness of breath, dysrhythmias and increased sensitivity to digitalis, hypotension, weak pulse, dilute urine, glucose intolerance Dx: dec serum K level ECG - flattened , depressed T waves, presence of “U” waves ABGs - metabolic alkalosis Medical Mgmt: diet ( fruits, fruit juices, vegetables, fish, whole grains, nuts, milk, meats) oral or IV replacement Nsg mgmt: monitor cardiac function, pulses, renal function monitor serum potassium concentration IV K diluted in saline monitor IV sites for phlebitis Normal ECG Hypokalemia Hyperkalemia  CALCIUM (Ca) Majority of calcium - bones and teeth Normal serum range 8.5-10.5 mg/dL Ca has an inverse relationship with PO4 FUNCTIONS 1. formation and mineralization of bones/teeth 2. muscular contraction and relaxation 3. cardiac function 4. blood coagulation 5. Promotes absorption and utilization of Vit B12 Regulation: GIT absorbs Ca+ in the intestine with the help of Vitamin D Kidney Ca+ is filtered in the glomerulus and reabsorbed in the tubules PTH increases Ca+ by bone resorption, inc intestinal and renal Ca+ reabsorption and activation of Vitamin D Calcitonin reduces bone resorption, increase Ca and Phosphorus deposition in bones and secretion in urine a. HYPERCALCEMIA Serum calcium > 10.5 mg/dL Etiology: Overuse of calcium supplements and antacids, excessive Vitamin A and D, malignancy, hyperparathyroidism, prolonged immobilization, thiazide diuretic s/sx: anorexia, nausea, vomiting, polyuria, muscle weakness, fatigue, lethargy Dx: inc serum Ca ECG: Shortened QT interval, ST segments inc PTH levels xrays - osteoporosis  Mgmt: 0.9% NaCl IV Phosphate Diuretics – Furosemide IM Calcitonin corticosteroids dietary restriction (cheese, ice cream, milk, yogurt, oatmeal, tofu) Nsg Mgmt: Assess VS, apical pulses and ECG, bowel sounds, renal function, hydration status safety precautions in unconscious patients inc mobility inc fluid intake monitor cardiac rate and rhythm b. HYPOCALCEMIA Calcium < 8.5 mg/dL Etiology: removal of parathyroid gland during thyroid surgery, Vit. D and Mg deficiency, Furosemide, infusion of citrated blood, inflammation of pancreas, renal failure, thyroid CA, low albumin, alkalosis, alcohol abuse, osteoporosis (total body Ca deficit) s/sx: Tetany, (+) Chovstek’s (+) Trousseaus’s, seizures, depression, impaired memory, confusion, delirium, hallucinations, hypotension, dysrythmia  Dx: dec Ca level ECG: prolonged QT interval Mgmt: Calcium salts Vit D diet (milk, cheese, yogurt, green leafy vegetables) Nsg mgmt monitor cardiac status, bleeding monitor IV sites for phlebitis seizure precautions reduce smoking Magnesium Mg Second to K+ in the ICF Normal range is 1.3-2.1 mEq/L FUNCTIONS 1. intracellular production and utilization of ATP 2. protein and DNA synthesis 3. neuromuscular irritability 4, produce vasodilation of peripheral arteries a. HYPERMAGNESEMIA M > 2.1 mEq/L Etiology: use of Mg antacids, K sparing diuretics, Renal failure, Mg medications, DKA, adrenocortical insufficiency s/sx: hypotension, nausea, vomiting, flushing, lethargy, difficulty speaking, drowsiness, dec LOC, coma, muscle weakness, paralysis, depressed tendon reflexes, oliguria, ↓RR  Mgmt: discontinue Mg supplements Loop diuretics IV Ca gluconate Hemodialysis Nsg mgmt: monitor VS observe DTR’s and changes in LOC seizure precautions b. HYPOMAGNESEMIA Mg < 1.5 mEq/l Etiology: alcohol w/drawal, tube feedings, diarrhea, fistula, GIT suctioning, drugs ie antacid, aminoglycosides, insulin therapy, sepsis, burns, hypothermia s/sx: hyperexcitability w/ muscle weakness, tremors, tetany, seizures, stridor, Chvostek and Trousseau’s signs, ECG changes, mood changes  Dx: serum Mg level ECG – prolonged PR and QT interval, ST depression, Widened QRS, flat T waves low albumin level Mgmt: diet (green leafy vegetables, nuts, legumes, whole grains, seafood, peanut butter, chocolate) IV Mg Sulfate via infusion pump Nsg Mgmt: seizure precautions Test ability to swallow, DTR’s Monitor I and O, VS during Mg administration The Anions CHLORIDE PHOSPHATES BICARBONATES Chloride (Cl) The MAJOR Anion in the ECF Normal range is 95-108 mEq/L Inc Na reabsorption causes increased Cl reabsorption FUNCTIONS 1. major component of gastric juice aside from H+ 2. together with Na+, regulates plasma osmolality 3. participates in the chloride shift – inverse relationship with Bicarbonate 4. acts as chemical buffer a. HYPERCHLOREMIA Serum Cl > 108 mEq/L Etiology: sodium excess, loss of bicarbonate ions s/sx: tachypnea, weakness, lethargy, deep rapid respirations, diminished cognitive ability and hypertension, dysrhytmia, coma  Dx: inc serum Cl dec serum bicarbonate Mgmt: Lactated Ringers soln IV Na Bicarbonate Diuretics Nsg mgmt: monitor VS, ABGs, I and O, neurologic, cardiac and respiratory changes b. HYPOCHLOREMIA Cl < 96 mEq/l Etiology: Cl deficient formula, salt restricted diets, severe vomiting and diarrhea s/sx: hyperexcitability of muscles, tetany, hyperactive DTR’s, weakness, twitching, muscle cramps, dysrhytmias, seizures, coma  Dx: dec serum Cl level ABG’s – metabolic alkalosis Mgmt: Normal saline/half strength saline diet ( tomato juice, salty broth, canned vegetables, processed meats and fruits avoid free/bottled water) Nsg mgmt: monitor I and O, ABG’s, VS, LOC, muscle strength and movement Phosphates (PO4) The MAJOR Anion in the ICF Normal range is 2.5-4.5 mg/L Reciprocal relationship w/ Ca PTH inc bone resorption, inc PO4 absorption from GIT, inhibit PO4 excretion from kidney Calcitonin increases renal excretion of PO4 FUNCTIONS 1. component of bones 2. needed to generate ATP 3. components of DNA and RNA a. HYPERPHOSPHATEMIA Serum PO4 > 4.5 mg/dL Etiology: excess vit D, renal failure, tissue trauma, chemotherapy, PO4 containing medications, hypoparathyroidism s/sx: tetany, tachycardia, palpitations, anorexia, vomiting, muscle weakness, hyperreflexia, tachycardia, soft tissue calcification  Dx: inc serum phosphorus level dec Ca level xray – skeletal changes Mgmt: diet – limit milk, ice cream, cheese, meat, fish, carbonated beverages, nuts, dried food, sardines Dialysis Nsg mgmt: dietary restrictions monitor signs of impending hypocalcemia and changes in urine output b. HYPOPHOSPHATEMIA Serum PO4 < 2.5 mg/dl Etiology: administration of calories in severe CHON-Calorie malnutrition (iatrogenic), chronic alcoholism, prolonged hyperventilation, poor dietary intake, DKA, thermal burns, respiratory alkalosis, antacids w/c bind with PO4, Vit D deficiency s/sx: irritability, fatigue, apprehension, weakness, hyperglycemia, numbness, paresthesias, confusion, seizure, coma  Dx: dec serum PO4 level Mgmt: oral or IV Phosphorus correction diet (milk, organ meat, nuts, fish, poultry, whole grains) Nsg mgmt: introduce TPN solution gradually prevent infection The nursing care plans states to observe for hyperkalemia. The nurse should recognize that the greatest risk of hyperkalemia is: a. tetany c. cardiac arrest b. fluid overload d. internal bleeding The nursing care plans states to observe for hyperkalemia. The nurse should recognize that the greatest risk of hyperkalemia is: a. tetany c. cardiac arrest b. fluid overload d. internal bleeding A nurse is preparing to care for a client with potassium deficit. The nurse reviews the client’s record and determines that the client is at risk of developing the potassium deficit because the client: a. Is on nasogastric suction b. has a history of renal disease c. has a history of addison’s diseased. Is taking potassium sparing diuretic A nurse is preparing to care for a client with potassium deficit. The nurse reviews the client’s record and determines that the client is at risk of developing the potassium deficit because the client: a. Is on nasogastric suction b. has a history of renal disease c. has a history of addison’s diseased. Is taking potassium sparing diuretic Acid Base Balance Acid - substance that can donate or release hydrogen ions ie Carbonic acid, Hydrochloric acid ** Carbon dioxide – combines with water to form carbonic acid  Base - substance that can accept hydrogen ions Ie Bicarbonate  BUFFER- substance that can accept or donate hydrogen - prevent excessive changes in pH TYPES OF BUFFER 1. Bicarbonate (HCO3): carbonic acid buffer (H2CO3) 2. Phosphate buffer 3. Hemoglobin buffer Dynamics of Acid Base Balance Acids and bases are constantly produced in the body They must be constantly regulated CO2 and HCO3 are crucial in the balance A HCO3:H2CO3 ratio of 20:1 should be maintained Respiratory and renal system are active in regulation Kidney - Regulate bicarbonate level in ECF 1. RESPIRATORY/METABOLIC ACIDOSIS - kidney excrete H and reabsorbs/generates Bicarbonate 2. RESPIRATORY/METABOLIC ALKALOSIS - kidney retains H ion and excrete Bicarbonate Lung - Control CO2 and Carbonic acid content of ECF 1. METABOLIC ACIDOSIS - increased RR to eliminate CO2 2. METABOLIC ALKALOSIS - decreased RR to retain CO2  pH - measures degree of acidity and alkalinity - indicator of H ion concentration - Normal ph 7.35-7.45  ACIDOSIS - decreased pH; < 7.35 - increased Hydrogen  ALKALOSIS - increased pH-; > 7.45 - decreased Hydrogen ACUTE AND CHRONIC METABOLIC ACIDOSIS - Low pH - Increased H ion concentration - Low plasma Bicarbonate Etiology: diarrhea, fistulas, diuretics, renal insufficiency, TPN w/o Bicarbonate, ketoacidosis, lactic acidosis S/sx: headache, confusion, drowsiness, inc RR, dec BP, cold clammy skin, dysrrythmia, shock  Dx: ABG – low Bicarbonate, low pH, Hyperkalemia, ECG changes Rx: Bicarbonate for pH < 7.1 and Bicarbonate level < 10 monitor serum K dialysis ACUTE AND CHRONIC METABOLIC ALKALOSIS High pH Decreased H ion concentration High plasma Bicarbonate Etiology: vomiting, diuretic, hyperaldosteronism, hypokalemia, excesive alkali ingestion s/sx: tingling of toes, dizziness, dec RR, inc PR, ventricular disturbances  Dx:ABG – pH > 7.45, serum Bicarbonate > 26 mEq/L, inc PaCO2 Rx: restore normal fluid balance correct hypokalemia Carbonic anhydrase inhibitors ACUTE AND CHRONIC RESPIRATORY ACIDOSIS Ph < 7.35 PaCO2 > 42 mmHg Etiology: pulmonary edema, aspiration, atelectasis, pneumothorax, overdose of seatives, sleep apnea syndrome, pneeumonia s/sx: sudden hypercapnia produces inc PR, RR, inc BP, mental cloudinesss, feeling of fullness in head, papiledema and dilated conjunctival blood vessels  Dx: ABG – pH < 7.35 PaCO2 - > 42 mmHg Rx: improve ventilation pulmonary hygiene mechanical ventilation ACUTE AND CHRONIC RESPIRATORY ALKALOSIS pH > 7.45 PaCO2 < 38 mmHg Etiology: extreme anxiety, hypoxemia s/sx: lightheadednes, inability to concentrate, numbness, tingling, loss of consciousness  Dx: ABG – pH > 7.45 PaCO2 < 35 dec K dec Ca Rx: breathe slowly sedative ARTERIAL BLOOD GAS ANALYSIS Parameter Normal Value pH 7.35 – 7.45 PaCO2 35 – 45 mmHg HCO3 22-26mEq/L O2 saturation 93 - 98% Evaluating ABG’s 1. Note the pH pH = 7.35 – 7.45 (normal) pH = < 7.35 (acidosis) pH = > 7.45 (alkalosis) compensated – normal pH uncompensated – abnormal pH 2. Determine primary cause of disturbance 2.1 pH > 7.45 a. PaCo2 < 40 mmHg – respiratory alkalosis b. HCO3 > 26 mEq/L – metabolic alkalosis 2.2 pH < 7.35 a. PaCo2 > 40 mmHg – respiratory acidosis b. HCO3 < 26 mEq/L – metabolic acidosis 3. Determine compensation by looking at the value other than the primary disturbance pH PaCO2 HCO3 7.20 60 24 Uncompensated mmHg mEq/L Respiratory acidosis 7.40 60 37 Compensated mmHg mEq/l Respiratory acidosis  4. Mixed acid-base pH 7.21 Dec acid disorders PaCO2 52 Inc acid Metabolic and Respiratory Acidosis HCO3 13 Dec acid Thank You!