ATI Peds 3 Lect 1 Iv Fluids Dehydration Exam Study Guide

What is the total body of water newborns? 80% TBW decrease gradually in the first year to? 60% ICF is ________ of total body water. 2/3 ECF mayor components Na+, Cl- ICF mayor components are K, PO4 ECF contains proteins T/F True ____ reduces secretions to 1,500 ml/day duodenum _____ reduces secretions to 250 ml a day colon Urine output is maintained to 800- 1,500 ml Osmolality number of solute particle per volume, is established by the electrolytes. Serum Osmolality (normal range) 285-290 Cell membrane permeability permits free water and urea passage but no electrolytes (Na/K). T/F T Total body fluid requirements maintenance fluid needs (normal basal state) + deficit + ongoing losses. maintenance fluid for children is related to surface area and weight maintenance fluid for a child 80 ml/kg/day to 160 ml/kg/day in VLBW. Insensible water losses are _____ This is considering a normal basal state. (sweat, breathing) 12 ml/kg/day. What happens when there is a decreased in blood vol? Decreased bp, increase angiotensin -- stimulates hypothalamus = increase thirts, intake of water -- decrease blood osmolality what is the mechanism in order to decrease osmolality when the it's increased? Osmoreceptors trigger thirst inducing water intake MC cause of fluid loss • vomiting or diarrhea. Etiology of Dehydration in Children (1) decreased intake e.g. stomatitis (2) increased fluid output e.g. gastroenteritis, renal (3) increased insensible losses e.g. fever. Burns 4) 3rd space losses e.g. ascites, nephrotic syndrome If there is mild or moderate volume dehydration with NO hemodynamic changes, what is the appropriate fluid therapy? oral hydration (Pedialyte) 2 multiple choice options what are so general signs of dehydration? mucous membrane, delayed capillary refill, tachycardia, fontanelle sunken, skin turgor, urine outpout C dehydration is more than __ reduction of total water, ECV particularly 5% 2 multiple choice options degree of dehydration if MODERATE CHILD 6% (60 ml/kg) INFANT 10% (100 ml/kg) tenting Dry depressed irritable slightly increased decreased degree of dehydration if Mild Children ( 10 kg ) Infant ( 10 kg ) Turgor skin fontanelle CNS PULSE Urine output degree of dehydration if severe 9% (90 ml/kg) 15% (150 ml/kg) none clammy sunken lethargic increased Anuric degree of dehydration [Pre Illness weight(kg) - actual weight (Kg)]/ pre illness weight(kg) X 100% An 18 month old girl with a 2 day history of vomiting, diarrhea and decreased oral intake,is seen in clinic,you estimate her to be 5% dehydrated. Of the following, the most likely additional examination finding is: A. Bounding peripheral pulses B. Capillary refill of 4 seconds C. Hypotension D. Periorbital edema E. Tachycardia E. Tachycardia A 12 month old male is brought to ER due to vomiting and diarrhea since 2 days ago. His parents refer he is refusing to eat, and would not drink anything. The diarrhea persist, although the vomits resolved. Upon arrival you observe that the patient is irritable and lethargic. His mucous membranes and tongue appear dry, and skin turgor over the abdomen is slightly decreased. His mother reports that the patient has had only two wet diapers today and says the urine in his diapers was dark in color. Previous weight 12 kg (26 lb) at the clinic last week. However, today weight is 11 kg (24 1/2 lb). What degree of dehydration does this patient presents? 8 % Metabolic acidosis, loss of bicarbonate diarrhea Metabolic alkalosis, hydrogen is los vomit Hypernatremia (HYPEROSMAL) water to shift from the ICF and interstitial space into the intravascular space trying to maintain vascular volume. - when water is loss or deprived, thirst is stimulated. Hyperosmolality Triggers increase in ADH and restricts water loss •With hypotonic fluid replacement (eg, free water), Hyponatremia (Hyposmol) fluid shifting out of the intravascular space into the cell at the expense of vascular volume - when drinking lots of of water or too little water -triggers secondary hyperaldosterism In a hypernatremia correction with hypotonic fluid what can happen? serum Na+ decreases, hyposmal Isosmolal Proportional loss Na+ & H2O, Chronic diarhea, burns, vomit Most common type of dehydration is seen. Constitute about 80% cases of acute gastroenteritis. Isotonic Normal serum sodium levels range from 130-150 mEq/L. The severity of isotonic dehydration depends on the _____ of illness and the amount of fluid and electrolyte lost. duration Vomiting presentation and tx hypovolemia hypokalemia isonatremia metabolic alkalosis secondary to H+ loss 2ry to elevated aldosterone Tx: isotonic Saline Hyponatremic Dehydration •Most common electrolyte imbalance •sodium loss is more than the water loss. Then the extracellular fluid is shifted into cells leading to cellular edema, rise in intracranial tension and seizures (115 mmol/l). •Patients present with signs of profound volume depletion and shock. Types of hypovolemic dehydration hypovolemic hyponatremia, hypovolemic hypernatremia, euvolemic Hypovolemic hyponatremia : (think kidney!!) •decrease osmolarity(Na) more than fluid volume loss •causes: salt or protein wasting nephropathies, diuretic excess, mineralocorticoid deficiency , urine Na20 KIDNEYS CANT WORK WITH FREE H20 EXCRETION Hypervolemic hyponatremia •edema ,increase total body water •Causes: acute and chronic renal failure, cirrhosis, nephrotic syndrome,CHF Euvolemic hyponatremia no edema, total body water increase w/o change in Na. Causes: hypothyroidism, polydipsia Dz: SIADH, addison's disease, psychogenic polydipsia SIADH excessive ADH from posterior pituitary, low Na, no HTN, urine Na 20 elevated ADH Tx Fluid restriction, 0.9 NSS, Demeclocycline Addison's disease Tx: Asymptomatic: free water restriction Moderate hyponatremia tx IV normal saline, Loop diuretics may be added (125-129 mmol/l) Severe hyponatremia TQ acute treatment= 10-12 mL bolus of 3% saline (125 mmol/L) Seizure at 115 mmol/L Serum Na should be corrected slowly—by ≤ 10 mEq/L over 24 h to avoid osmotic demyelination syndrome Na rise 2-4 mEq/L /hr What is a complication of Euvolemic hyponatremia? central pontine myelinolysis: osmotic demyelination less than 100 mOsm/kg primary polydipsia greater than 100 mOsm/kg a high ADH What is used to differentiate ○between hyponatremia secondary to hypovolemia and the SIADH? Urinary sodium concentration With SIADH (and salt-wasting syndrome), the urine sodium is greater than 20-40 mEq/L Hypernatremic Dehydration •Na concentration 150 mEq/L –ECF hypertonicity . –Movement of fluid from the inside the cell to the extracellular fluid causes intracellular dehydration with intravascular volume preservation. No signs of dehydration. Hypernatremic Dehydration ETIOLOGY •Causes: –FREE WATER loss most common (eg Diabetes insipida, water access) –sodium excess (formula preparation) –Excess ratio of water loss vs Na ( diarrhea) –Iatrogenic •Mortality: 20% •Neurologic signs are the most common symptom. Hypernatremic Dehydration SS Neurologic signs are the MC symptom. excessive thirst, lethargy, irritability, hyperreflexia, seizures, weakness, fever, doughy skin. •Urine Osmolality: –extrarenal losses show urine sodium levels of less than 20 mEq/L Central DI –renal losses: urine sodium values are more than 20 mEq/L. Eg nephrogenic DI Hypertonic Dehydration COMPLICATION ICH. Free water deficit FW =0.6 (weight Kg)x (1-(140/Na)) In hypertonic dehydration administering fluids •Give ½ the FW deficit + maintenance in 24 hrs •Complete hydration in 48 hrs •IVF’s = D5W +1/4 NS + 20 KCL •Avoid dropping Na 15 mEq /L / day Hypernatremia causes Na gain: Iatrogenic, Formula incorrectly mixed, Hyperaldosteronism Due to H2O loss: Inadequate water intake, Severe profuse diarrhea, DI, Burns, Diuretics Due to H2O + Na loss –Renal intrinsic and extrinsic A 3-month-old infant has had diarrhea for 4 days. Findings include blood pressure 80/40, pulse 150, doughy skin and sunken eyes. Electrolytes are creatinine 1.0, BUN 60, sodium 170, potassium 6.0, chloride 132, and bicarbonate 15. Fluid therapy is instituted and 12 hours later the patient has a generalized seizure. The most likely explanation for these findings are: A. Hypoglycemia B. Hyperkalemia C. Idiopathic epilepsy D. Rapid correction of hypernatremia E. Rapid correction of metabolic acidosis D. Severe states of either hyper or hyponatremia may lead to dangerous fluid shifts in the central nervous system.Correction of a very high sodium level should be done slowly to prevent seizures or central pontine myelinosis.