Endocrine/Fluid and Electrolytes/Metabolic disorders x 2
To avoid rapid fluid shifts, hyponatremia should be corrected at a rate of
0.5 to 1 mEq/hour
Recommended dosage of potassium chloride
0.5-1 mEq/kg/dose not to exceed 20 mEq per dose at a rate of 0.5 mEq/kg/hour
CSW immediate course of action
0.9% saline fluid bolus to correct low sodium level slowly
An 11-month-old infant weighing 10 kg in septic shock presents with a potassium of 7.6 meq/dL and peaked t-waves on EKG. What is the most appropriate emergent treatment?
1000mg of calcium gluconate
Dehydration fluid deficit Moderate
100mL/kg
Full maintenance rate 24kg
100mL/kg for 1st 10kg (1000 mL) 50mL/kg for next 10kg (500mL) 20mL/kg for last 4 kg (80mL) =1580mL in 24 hours 1580/24=68mL/hour 2/3 of 68mL/hour is approximately 43mL/hour
Emergent management of hyperkalemia includes
100mg/kg of calcium gluconate administered IV or Calcium chloride 20mg/kg
What is the recommended goal serum sodium correction level for a child with severe hyponatremia who presents with status epilepticus
14-16 mEq/L in the first 12 hours
Dehydration fluid deficit Severe
150mL/kg
Normal cortisol levels
18-20 mg/dL (500-550 nmol/L)
What is the appropriate rate of rise in serum sodium for a patient with asymptomatic hyponatremia
2-4 mEq/L every 4 hours or 10-20 mEq/L in 24 hours
Calculate the hourly rate of IV fluid infusion for a 4 year old who weighs 44 lbs and requires maintenance fluid therapy
20kg 1st 10kg = 1000 2nd 10kg=500 1500/24 hours = 62.5 mL/hour
Correct severe hyponatremia with
3% hypertonic saline initially to increase the sodium level in order to prevent further seizure activity. Then goal is to then slowly correct sodium with a goal of 12-14 mEq/L/day to normal levels
What is the first step in managing a child who is diagnosed with DKA and is suspected of developing crebral edema
3% saline bolus
If the serum sodium level was 120 mEq/L, calculate the amount of 3% hypertonic saline (513 mEq of sodium/L) needed to correct his serum sodium level to 125 mEq/L. Kid weighs 20kg
30 mL 20 x 0.6 x 125-120 = 60 mEq 30 mEq x 0.513mEq/mL (3% saline) = 30mL
Which of the following is the correct IV fluid rate for a child who weighs 24 kg and is receiving fluids at 2/3 maintenance?
43 mL/hour
Vasopressin (ADH) in management of DI is initiated and titrated until urine output is less than
4mL/kg/hour
4-2-1 Method for calculating fluid requirements
4ml for first 10 kg 2ml for next 10 kg 1ml for anything over 20kg
Dehydration fluid deficit Mild
50mL/kg
2/3 maintenance fluids
65 mL/hour
A 2-month-old, born at 32 weeks gestation weighs 4 kg and is receiving Similac Sensitive 24 cal/oz at 15 mL/hour via NG tube. How many kcals/kg is the infant receiving?
72
A 4-month-old presents with nonbilious, nonbloody vomiting and diarrhea. VS: T 37°C, HR 160 beats per minute, BP 60/40 mmHg, RR 48 breaths per minute. Clinical exam reveals irritable infant with sunken fontanel, dry mucous membranes, and capillary refill of 4 seconds. His current weight is 4.9 kg. He has had no wet diapers for the past 4 hours. Which of the following is his fluid deficit?
735mL
In determining the presence of adrenal insufficiency, what cortisol level would support the diagnosis?
<16 mg/dL (440 nmol/L)
A 5 yr old boy is on post op day 2 from an astrocytoma resection. He is awake, alert, and has been tolerating oral feeds. His morning lab values reveal a serum osmolarity of 250 mOsm, serum sodium of 133 mEq/L and urine sodium of 100 mEq/L. What intervention is best to correct is electrolyte imbalance
Allow him to drink fluids that he likes and can tolerate
What genetic syndrome is associated with hypochloremia
Bartter syndrome
When rehydrating a child with diabetic ketoacidosis, when is glucose added to the IV fluids?
Blood glucose is < 300 or dropping faster than 100 per hour
In a pt that presents with DKA symptoms what is the first test should you consider
Blood glucose test low serum pH and bicarbonate level assist in supporting dx
infant presenting with hyperkalemia and hyponatremia as well as significant dehydration
CAH
15 yr old crani for AV malformation. Post op day 2 presents with generalized 2 min seizures following he was lethargic. Lab values serum sodium 124 serum osmolarity 200, urine sodium 160, urine osmolarity 350 and urine specific gravity 1.035. Dx
CSW- low serum sodium/osmolarity high urine osmolarity and specific gravity
Initial treatment of hyperkalemia with ECG changes includes which one of the following
Calcium chloride 10 mg/kg central venous catheter Calcium Gluconate 100 mg/kg peripheral IV Shifts potassium intracellular and remove from circulation
What is a potential complication of rapid correction of hyponatremia
Central pontine myelinolysis
A febrile 2-year-old with a history of prematurity with chronic lung disease and meningitis has a serum sodium of 128 meq/dL, serum osmolarity of 230 and urine sodium of 120. What is the most likely diagnosis?
Cerebral Salt wasting
A 6-day-old infant with no other signs of illness presents with severe dehydration and is found to have a serum potassium of 6.3, sodium of 130 and glucose of 95. The most likely diagnosis is:
Congenital adrenal hyperplasia (CAH)
What is the best strategy to normalize the serum sodium value
Correct sodium level at a rate of 0.5-1 mEq/hour
An adolescent who weighs 54 kg is admitted with a diagnosis of status asthmaticus and is placed on continuous albuterol therapy. His orders include potassium supplement and IV fluids at 2/3 maintenance. What is the best choice for IV infusion
D5. 45 NS with 20 mEq Kcl/L at 60 mL/hour
A 9 yr old girl dx with DM two years ago presents with headache, vomiting, and upper abd pain. She was at a family picnic the day before and had a sleepover with her cousins the night before. What is the most likely dx
DKA
administer a fluid bolus of 10 mL/kg (50mL) and start D5 0.9NS for hyponatremia at maintenance rate (4mL x 5kg = 20 mL/hour)
Dehydrated 4.9kg infant would be administered
A 12 month old child has had diarrhea for 6 days and has lost 1.5lbs since his last visit 3 weeks prior. He has tears and has had two wet diapers in the past 5 hours, and is taking sips of water and milk. What is the first step in his management
Determining level of dehydration by clinical assessment
A breastfeeding one-week old infant is seen in the ED for nasal congestion, which does not require intervention. Her birthweight was 6lbs, 3 ounces (2806kg) at term. Her weight today is 5lbs, 2ounces (2325kg). What is the best management?
Due to excessive weight loss, assess intake and output and evaluate breastfeeding
A 13-year-old is diagnosed with IDDM. He learns insulin dosing and carbohydrate counting. He adds a nutrition app to his cell phone and wants to use this with each meal. He does not want the school nurse to be involved with checking his blood sugar but wants to obtain them himself. Based on his developmental level, which is most appropriate?
Encourage the teen to have a discussion with the school nurse with his plans and her support
When treating a patient with central DI, what is appropriate management
Fluid replacement, titration of vasopressin continuous infusion
Symptoms of congenital hypothyroidism include
Hoarse cry, large fontanels, and hypothermia constipation and bradycardia
When admitting a child with a history of adrenal insufficiency for a surgical procedure, which one of the following medications needs to be ordered for the periop period
Hydrocortisone
Peaked T waves and widened QRS.
Hyperkalemia ***Drugs that CAUSE Hyperkalemia: (1) B-blockers (2) Digitalis (3) Succinylcholine
The acute treatment of clinically significant hypophosphatemia includes what in a patient with normal renal fx and serum potassium level of 2.8 mEq/L and serum sodium level of 140 mEq/L
IV potassium phosphate infused over 4-6 hours
What may contribute to hypernatremia, especially in a young infant
Inappropriately concentrated infant formula
A child with Graves disease will typically have which of the following lab findings
Increased T3 and T4, decreased TSH and positive TSI
When discussing the long term care of nephrogenic DI with a patient and family, the counseling will include instructions for which of the following
Intake and output monitoring
When ordering an insulin infusion, it is important for the health care team to be aware of
Iv tubing must be completely flushed with the insulin
A 16-year-old is brought to the ED urgently after a day of football practice in August. He reported having some diarrhea the past two days. In assessing his hydration level, in addition to oliguria, which signs and symptoms are most consistent with 10% dehydration?
Less active than usual, sticky oral mucosa, slightly diminished skin turgor and tachycardia.
What is a finding in a child with hypophosphatemia
Muscle weakness
What findings are associated with hypokalemia in an athlete
Muscle weakness/fatigue Ventricular arrhythmias Flattened T waves decreased diastolic fx
PTH targets which of the following organs to regulate calcium levels
Musculoskeletal PTH triggers increased bone resorption causing elevation in serum calcium and serum phosphate kidney PTH stimulates the reuptake of calcium and magnesium and increases phosphorus excretion GI PTH activates the enzyme responsible for vit D absorption, which then controls the absorption of intestinal calcium
A dehydrated 4-month-old who weighs 4.9 kg, has electrolyte results of: Na+ 128 meq/dL, Cl 96 meq/dL, K+ 4.8 meq/dL, CO2 13 mg/dL, BUN 26 mg/dl, Cr 0. 5 mg/dL & Glucose 82 mg/dl. Which of the following IV fluid replacement therapies should be started?
NS 50 mL, and start D5 NS @ 20 mL/hr
5 yr old pt chronic renal failure in PICU for acute illness and is noted to have polyuria with urine output of 6 mL/kg/hour, serums sodium 167 mEq/L, urine specific gravity of 1.001 and serum osmolality of 300 mOsm/kg. ICU initiated fluid replacement and a vasopressin infusion. Despite titrating the vasopressin up every 30 min, the patient's urine output remains 6 mL/kg/hour. What is the likely cause
Nephrogenic DI (resistant to vasopressin)
The most important assessment in a child with DKA
Neurological status
A treatment of DKA may result in hypomagnesemia because
Osmotic diuresis leads to depletion of total body magnesium stores
an adolescent who is thin admits to purposely vomiting after eating large meals. What finding would be associated with bulimia nervosa
Peripheral edema
What findings are diagnostic of diabetes insipidus
Polyuria, urine specific gravity 1.001, and serum osmolality of 300 mOsm/L
A 30 kg child has had repair of a congenital heart lesion, with poor cardiac fx, and currently a potassium level of 2.2 mEq/L. Cardiac monitor indicates intermittent premature ventricular contractions. What is the most appropriate choice for potassium replacement
Potassium chloride 20 mEq (0.67 mEq/kg) over 90 minutes
Hypermagnesium Causes
Renal failure Excessive magnesium intake/supplementation Tumor Lysis syndrome
What is appropriate management for SIADH
Restrict the IV fluid to <75% of total daily maintenance is needed to decrease the free-water reabsorption and excess sodium intake while addressing the underlying cause of SIADH
5 yr old postop day one thoracic rib expansion. overnight urine output decreased to < 0.5 mL/kg/hour. His morning labs serum sodium 130 mEq/L, serum osmolarity 270 mOsm/L BUN 8 mg/dL, urine specific gravity 1.030, urine osmolarity 230 mOsm/L and urine sodium 35 mEq/L
SIADH- hyponatremia, decreased serum osmolarity, increased urine osmolarity, increased specific gravity, normal BUN as well as decreased urine output in the face of a euvolemic fluid status.
What are possible clinical signs of both hyponatremia and hypernatremia
Seizures, irritability, lethargy
Complaining about headache. BP 75/40 and urine output is 2-3 mL/kg/hour. What lab findings are consistent CSW
Serum sodium 130 mEq/L, serum osmolarity 275 mOsm/kg, urine sodium 90 mEq/L, urine specific gravity 1.005
Cerebral salt wasting
Serum sodium <135 mEq/L Serum osmolarity <280 mOsm/kg Urine sodium > 80 mEq/L Urine specific gravity >1.010 due to excess sodium excreted in the urine
Brain tumor resection, normotensive, war, and well perfused with normal pulses and cap refill time of 3 seconds. Without urine for 10 hours. What lab results are consistent with SIADH
Serum sodium <135 mEq/L serum osmolarity <280 mOsm/kg urine sodium >30 mEq/L Urine osmolarity > 200 mOsm/kg
What is the most appropriate treatment for CSW
Sodium repletion
Symptoms of congenital hyperthyroidism
Tachycardia, small fontanels, and hypothermia, irritability, vomiting, and poor weight gain
Holliday-Segar method
Used to calculate water baseline requirements: 2-10 kg of body weight = 100mL/kd/d 11-20 kg of body weight= 1,000 mL + 50 mL/kg for each kg between 11-20 21-70 kg of body weight = 1500 mL + 20 mL/kg for each kg between 21-70 Calculate the total volume for 24 hours then divide by 24 to reach the hourly IV fluid rate
The management of hyponatremia is based on the etiology and typically includes what
Volume expansion, fluid restriction, or diuretic use
pH evaluates
acid-base status
Bicarbonate
assess acid-base and fluid status
BUN/creatinine
assess in evaluating her fluid status
Swelling of the hands and feet related to hypoalbuminemia may be noted in patients with
bulimia nervosa and other eating disorders in which nutrition is challenged
DKA-allowing blood sugar to drop too fast can lead to
central pontine myelinolysis
Serum sodium correction must be done in a slow, controlled manner to avoid
central pontine myelinolysis
SIADH has more of a
decreased urine output and serum osmolality of 250 mOsm/L
SIADH is characterized by
excess circulating blood volume which will result in a low serum sodium value, high urine sodium, and low urine output.
Central pontine myelinolysis occurs when
free water rapidly moves out of the cells to compensate for the hypertonicity of the extracellular fluid, resulting in shrinking of the brain cells and ultimately demyelination of the axons.
Laryngospasm and tetany (intermittent muscle spasms) maybe symptoms of
hyperphosphatemia
Graves disease is a form of
hyperthyroidism
DKA treatment with insulin actually stimulates cellular uptake of magnesium which leads to
hypomagnesemia
diabetes insipidus
hyposecretion of ADH excessive urine output of dilute urine Urine specific gravity of < 1.005 increased serum sodium increased osmolality
Bartter syndrome
includes a group of autosomal recessive genetic disorders defined by an impairment of salt reabsorption with significant salt wasting, hypokalemic metalbolic alkalosis and hypercalciuria
volume is 15 mL/hour for 24 hours per day which = 360mL per day. Next, determine how many ounces per day she is receiving - 360mL divided by 30 mL = 12 ounces per day. 12 ounces x 24 cal/ounce = 288kcal/day. 288 kcal divided by 4 kg = 72 kcal/kg/day.
kcals/kg
Increased T3/T4 and decreased TSH
lab findings for hyperthyroidism
Decreased T3/T4 and increased TSH
lab findings for hypothyroidism
Central DI is responsive to administration of vasopressin because it is characterized by
low circulating levels of ADH
Osmotic diuresis (Mannitol) leads to depletion of total body
magnesium stores
Critically low phosphorus levels <1 mg/ dL can result in symptoms that include
muscle weakness including respiratory muscle function.
A 13-year-old known diabetic has increased thirst, polyuria, abdominal pain and nausea. Her blood glucose is 485 and she has ketones in her urine. What additional laboratory information is warranted emergently?
pH, HCO3, BUN and creatinine
Potassium phosphate replaces
phosphorus supplementation administered over 4-6 hours
Diagnostic criteria for HHS
plasma glucose > 600 serum bicarb > 15 arterial pH > 7.3 Serum osmolality >320 ABSENT urine or serum ketones
Diabetes insipidus results in
polyuria, polydipsia massive dilute urine output, reduced intravascular volume, and increased serum sodium value.
Potassium phosphate should be administered slowly, as rapid infusion may result in
renal failure, hypocalcemic tetany, hyperphosphatemia, and ECG changes
To avoid central pontine myelinolysis serum sodium levels should not
rise more than 10 mEq/24 hours
Albuterol administration can result in decreased
serum potassium levels
A child with adrenal insufficiency will require higher doses of glucocorticoid administration during times of
stress
Hypophosphatemia may be associated with
thrombocytopenia