Exam 1 Ranges, Facts, and Equations to Memorize Flashcards
What changes to TPN should be considered in patients with cardiac disease?
Fluid restriction (check minimal volume), avoid overfeeding
What amount of phosphate should you give if a patient’s phosphate is 1.6 - 2.2?
0.64 mMol/kg
What is essential to identify when treating respiratory acidosis?
The cause – correction of the cause is usually enough to treat the patient. Avoid rapid correction.
Protein intake for child 1-7 yrs
1-2 g/kg/day
Topiramate/phentermine (Qsymia) important points
Titration schedule, greatest weight loss, REMS program because teratogen, avoid if HTN, CVD
What is the biggest disadvantage of using 3-in-1 TPN over 2-in-1 TPN?
In 3-in-1 TPN, you cannot visibly detect problems with the mix (such as CaPO4 crystallization) because of the cloudiness caused by the fat emulsion.
When loss of plasma HCO3 is replaced by chloride, what kind of metabolic acidosis is this?
Non-anion gap acidosis. If HCO3 loss is replaced by something else, this is anion gap acidosis.
Which acid/base disorder is MULEPAKS associated with?
Anion gap metabolic acidosis – HCO3 losses replaced by something other than Cl
Accelerated proteolysis, glycogenolysis, lipolysis, gluconeogenesis, insulin resistance, (-) nitrogen balance, and hypertriglyceridemia are metabolic responses to what?
Stress (could include sepsis, major surgery, major burns, etc.)
Who is bariatric surgery recommended for?
Pt BMI >40 or >35 w comorbidity
Vitamin C deficiency
Scurvy – connective tissue dysfunction
What is the goal nitrogen balance for a hospitalized patient?
+4 grams (but 0 for maintenance)
What is your goal daily calorie range for a major burn patient?
35 - 40 kcal/kg/day
What equivalents do we use when replacing calcium?
1 gram CaCl2 = 3 grams Ca gluconate = 270 mg elemental calcium
Which type of malnutrition usually develops over months to years?
Marasmus – protein/calorie malnutrition
Loss of GI acid, administration of HCO3-, impairment of renal function, and volume and chloride depletion can cause…
Metabolic alkalosis
Liraglutide (Saxenda) important points
Increase satiety by increasing insulin release, slow gastric emptying, titration, BEST for T2DM, REMS program, high # GI side effects
At what rate should calcium be replaced?
1 gram of calcium product per hour
What acid/base disorder is characterized by increase in pH, increase in bicarb, and increase in pCO2?
Metabolic alkalosis
What does MULEPAKS stand for?
Methanol intoxication, uremia, lactic acidosis, ethylene glycol, paraldehyde ingestion, aspirin (salicylates), ketoacidosis, sepsis
Citrate and acetate are metabolized to…
bicarb.
Caloric intake for infant 0-6 mos
100-110 kcal/kg/day
Caloric density of breastmilk
20 kcal/ounce
Niacin deficiency
Pellagra (dermatitis, diarrhea, dementia). alcoholics
What are the risks associated with bicarb therapy?
Overalkanization impairing O2 release, hypernatremia, hyperosmolality, CSF acidosis, electrolyte shifts (hypokalemia, hypocalcemia)
What is the henderson-hasselbach equation specified for our physiological bicarbonate buffer?
pH = 6.1 + log (HCO3-/0.03xpCO2)
Is urine the only way we lose nitrogen?
No. Also sweat, feces, respirations, GI fistula, wound drainage, burns, etc.
Dysphagia, dementia, head and neck surgery, esophageal obstruction, and trauma/burn are all indications for what type of nutrition?
Enteral nutrition
BUN, creatinine, glucose, Na, K, Cl, CO2, Mg, Ca, P, AST, ALT
1 - 2 times a week
What chronic disease is characterized by a chronically elevated pCO2?
COPD
What patients with respiratory acidosis should receive bicarb therapy?
Pts with pH < 7.15
What is the mMol to mEq equivalent for NaPhos?
1 mMol NaPhos = 1.33 mEq each Na and PO4
Which value is higher – BEE, REE, or TEE?
TEE (total energy expenditure) because TEE = BEE*activity factor. BEE just metabolic activity required to maintain life if no activity
In choosing whether to use chloride or acetate salts to administer cationic electrolytes, what ratio should you initially formulate them at?
2/3 salts chloride, 1/3 acetate. (May depend on pt acid/base balance)
Anxiety, pain, hypoxia, hypotension, high altitude, pulmonary edema, pulmonary embolism, and salicylate intoxication can all cause what acid/base disorder?
Respiratory alkalosis
What other disorder is it important to watch out for in calcium disorders?
Magnesium disorders
What other electrolyte disturbances are magnesium disturbances related to?
Potassium and calcium
What is always the first step in writing TPN for a patient?
Determining the correct weight to use
Caloric intake for child 1-7 yrs
60-80 kcal/kg/day
Zn deficiency
Poor growth, healing, immune response, sexual development
What is the caloric density of enteral formulations for normal patients? For fluid restricted patients?
1 kcal/mL normally; 2 kcal/mL for fluid restriction
Protein intake for infant 0-6 mos
2-3 g/kg/day
LR – maintenance, rehydration, or resuscitation?
Resuscitation
What is a common cause of isovolemic hypotonic hyponatremia?
SIADH
What is the mMol to mEq equivalent for KPhos?
1 mMol KPhos = 1.47 mEq each K and PO4
What is your goal daily protein range for an obese patient?
2 g/kg/day times IBW
If NG suctioning or vomiting is causing metabolic alkalosis, what adjunctive therapy can be used?
H2 antagonists or PPIs
What ions should monitor to look for refeeding syndrome?
Mg, Phos, and K
What is the calculation for dosing bicarb?
Dose (mEq) = (0.5 L/kg)(IBW)(12 mEq/L - actual HCO3) Give 1/3 to 1/2 calculated dose and monitor ABG ~1 mEq/kg may be given in cardiac arrest
Protein intake for preterm infant
3.5-4 g/kg/day
What size filter should be used for 3-in-1 TPN? 2-in-1 TPN?
1.2 micron for 3-in-1 or 0.22 for 2-in-1 (2 in 1 lacks fat so filter won’t disrupt emulsion)
If a patient has bowel ischemia, intractable vomiting/diarrhea, morning sickness, GI obstruction, ileus, inflammatory bowel disease, severe pancreatitis, NPO course >7 days, or short bowel syndrome, what type of nutrition is indicated?
Parenteral nutrition
What changes to TPN should be considered in patients with pulmonary failure?
Give 30% - 50% of total kcal as fat, protein 1 - 2 g/kg, limit carbohydrates (think about RQ)
Which of the following complications applies to enteral nutrition? Aspiration, GERD, pneumothorax, CVC infection, diarrhea, constipation, infusion pump failure, tube clogging
Aspiration, GERD, diarrhea, constipation, and tube clogging are all risks of enteral nutrition
What is your goal daily protein range for a burn patient?
2 - 2.5 g/kg/day
Riboflavin deficiency
Skin breakouts
How much “TPN space” do electrolytes usually take up?
~150 mL
What is a normal pH range?
7.35 - 7.45
NS – maintenance, rehydration, or resuscitation?
Resuscitation
True or false: Parenteral nutrition is safer, less costly, better for the GI tract, and less wasteful than enteral nutrition.
False – all of these benefits are true for enteral nutrition.
What changes to TPN should be considered in patients with short bowel syndrome?
High-carb, low-fat diet with vitamin B12 supplementation prn
When should calcium gluconate be used?
If only line in is peripheral and in non-acute/non-emergent situations
What are the two routes of parenteral nutrition?
Peripheral parenteral nutrition and central parenteral nutrition
In bicarbonate reabsorption, what is the net change in bicarbonate and H+?
One filtered HCO3 reabsorbed, no change in H+
In what disorder is it always necessary to calculate an anion gap?
Metabolic acidosis
Lorcaserin (Belviq) important points
Suppresses appetite thru serotonin pathways, good tolerability and dosing schedule, lower weight loss
Which are used for fluid expansion – crystalloids or colloids?
Colloids
Caloric intake for preterm infant
100-120+ kcal/kg/day
When treating saline responsive alkalosis, what should you monitor?
I/O, HR, BP, lung sounds, electrolytes, and edema
List specific monitoring parameters to assess fluid balance
UOP, HR, BP, CVP, MAP, wt, I/O, BUN/SCr ratio
How fast should a patient’s free water deficit be replaced?
1/2 over 1st day, then next half over next day or two
What two disorders is metabolic alkalosis broken down into?
Saline responsive and saline resistant metabolic alkalosis
Which acid/base disorders can be caused by salicylate toxicity?
Respiratory alkalosis from stimulation of breathing or metabolic acidosis from accumulation of organic acids.
What changes to TPN should be considered in patients with hepatic disease?
High calorie intake (35 kcal/kg/day), protein restriction if encephalopathy, sodium restriction if ascites or edema
Are decreased coronary and cerebral blood flow, increased angina, stimulation of anaerobic glycolysis, and seizures signs of academia or alkalemia?
Alkalemia
Increased mineralcorticoid activity, hypokalemia, and renal tubular chloride wasting cause what acid/base disorder?
Saline-resistant metabolic alkalosis
If a patient with metabolic alkalosis has a urinary chloride of 23 mEq/L, what kind of metabolic alkalosis do they have?
Saline-resistant metabolic alkalosis
What ion is hydrogen exchanged for when it is secreted?
Na+
What gas do chemoreceptors detect for ventilatory regulation?
PaCO2
In non-anion gap metabolic acidosis, what lab value should you use to distinguish between RTA type 2/4 vs RTA type 1?
Urine pH – will be >5.3 in RTA type 1 because kidney not able to secrete H+
Under what situations should a hypokalemic patient receive IV potassium?
If K
What blood gas do respiratory disorders involve?
CO2
What are our three buffers and which is the most prevalent?
Bicarbonate/carbonic acid, phosphate, and protein. Principal buffer = bicarbonate.
In what form are the three macronutrients given in parenteral nutrition?
Protein – crystalline amino acids (4 kcal/g) Carbs – dextrose (3.4 kcal/g) Fat – emulsion with glycerol (10 kcal/g)
Which is for fluid restricted patients – Albumin 5% or Albumin 25%?
Albumin 25%
What can an elevated INR indicate?
Long-term malnutrition
If a patient has an egg allergy, what part of a TPN might they react to?
Egg yolk phospholipid – fat part
What is your goal daily calorie range for a for an obese patient?
22 - 25 kcal/kg/day times IBW (kg) *permissive underfeeding*
What is your goal daily protein range for a moderate to severely stressed patient (trauma/surgery/ICU)?
1.5 - 2 g/kg/day
What electrolyte besides calcium is regulated by vitamin D and parathyroid hormone?
Phosphate
What do you use to treat hyperkalemia? (Correct order necessary)
- CaCl2, IVP 2. Insulin with D50W or NaHCO3 or albuterol 3. (If needed) Furosemide or hemodialysis or Kayexalate (only if GI intact)
1/2 NS – maintenance, rehydration, or resuscitation?
Maintenance
BUN, creatinine, glucose, Na, K, Cl, CO2, Mg, Ca, and P should all be measured ____ in an unstable patient.
Daily
Orlistat Xenical and Alli important points
Causes oily stools through mechanism of action, bad if absorptive issues already, good for T2DM or HLD patients
Putting anything but breastmilk/formula into bottle, giving child under 1 year honey, cow’s milk, choking hazards, or potential allergens – bad idea or good idea?
Bad idea
What do you treat first in hypovolemic hypernatremia?
Volume status if needed – use NS. Then restore free water deficit.
What is a goal respiratory quotient (RQ)?
0.85 - 0.95 (>1 indicates overfeeding)
What do you do to treat respiratory alkalosis?
Treat the underlying cause – ventilation settings, medically induced sedation, paralysis
mEq Na in NS
154
What do you always use to treat hypervolemic hypotonic hyponatremia?
Furosemide (3% saline only if symptomatic)
What do 3-in-1 TPNs have that 2-in-1 TPNs do not?
Fat
Diuretic therapy, vomiting and NG suctioning, blood transfusions and exogenous HCO3- administration result in what acid/base disorder?
Saline-responsive metabolic alkalosis
Glucose transporter influenced by insulin
GLUT4
Introducing 1 new food every 4-5 days, increasing serving size gradually, and emphasizing all food groups – bad idea or good idea?
Good idea
Shock, seizures, leukemia, hepatic/renal failure, DM, malnutrition, rhabdomyolysis, alcohol, metformin, NRTIs, propofol, and propylene glycol can all cause which of the causes in MULEPAKS?
Lactic acidosis
Besides shortness of breath, what other symptoms usually occur in respiratory acidosis?
HA, drowsiness, confusion, coma, seizures, tachycardia, hypotension
Fluid requirements for infant 11-20 kg
1000 mL/day + 50 mL/kg/day
Thiamin deficiency
Beriberi – muscle weakness/atrophy
Is the distal tubule responsible for reabsorbing bicarb or creating bicarb?
Creating bicarb – this is where H+ excretion mainly takes place and this is essential for bicarb synthesis.
Most common MIVF
1/2NS + D5W + 20mEq KCl
For making TPN, what is the standard stock concentration for dextrose? Fat? Protein?
Dextrose – 70% Fat – 20% Protein – 10%
Vitamin A deficiency
Night blindness
What treatment is usually enough for isovolemic hypotonic hyponatremia?
Water restriction with NS. If symptomatic, treat like hypervolemic hypotonic hyponatremia.
Which two RTAs are associated with hypokalemia?
Type I (because K+ pumped instead of H+) and type II (because enhanced bicarb loss triggers more aldosterone, which stimulates K+ secretion)
What is the most common cause of hypertonic hyponatremia?
Elevated blood glucose
Fluid requirements for infant 3-10 kg
100 mL/kg/day
At what rate can you administer IV potassium?
Without cardiac monitoring, 10 mEq/hr. With continuous cardiac monitoring, 20 mEq/hr. If emergent with severe hypokalemia, 40-60 mEq/hr.
What is a typical maximum carbohydrate utilization rate?
4 - 5 mg/kg/minute (up to 7 if trauma/burn)
What component of a TPN should be eliminated if a patient has an infection or sepsis?
Fat
Wt loss goal for pt BMI >30 or >25 w comorbidity
5-10% over 6 most without regain
Naltrexone/bupropion (Contrave) important points
CYP enzyme interactions, titration schedule, avoid if HTN, seizure, opioid addiction, high % nausea
Glucose transporter in liver
GLUT2
What general category of causes can lead to hypovolemic hypotonic hyponatremia?
Fluid losses – blood, GI fluid, loss from skin (burn)
What is your goal daily calorie range for a trauma/surgery/stressed patient?
25 - 30 kcal/kg/day
Under what circumstances should you use a nutrition body weight?
If actual bw is between 130% and 150% of IBW.
What acid/base disorder is characterized by a low pH, high CO2, and high HCO3?
Respiratory acidosis
True or false: If you have correctly calculated a patient’s nutrition requirements, there is no need to watch them for overfeeding or underfeeding.
False – patient’s response to nutrition support should be monitored closely – treat the patient, not the number
Protein intake for infant 6-12 mos
1.5-2 g/kg/day
Acute pancreatitis, high output proximal fistulas, intractable vomiting and diarrhea, GI ischemia, ileum, and nutrition need less than 7 days are all contraindications for what type of nutrition?
Enteral nutrition
What is the function of aldosterone?
Increased Na reabsorption and increased H+ and K+ secretion
What is your goal daily calorie range for a non-stressed, non-depleted patient?
20 - 25 kcal/kg/day
Fluid requirements for infant >20 kg
1500 mL/day + 20 mL/kg/day
Noradrenergic agent important points
For short-term management, potential for abuse, watch out if cardiovascular issues–tends to aggravate
How do carbonic anhydrase inhibitors help in saline responsive metabolic alkalosis?
They decrease bicarb reabsorption in the proximal tubule. Unfortunately, they also cause K+ wasting.
What are patients at risk for if they suffered weight loss of 5-10% body weight in 6 months, had abnormal dietary intake for 1 month, or had anorexia, nausea, vomiting, or diarrhea for a few days?
Moderate malnutrition
What is your goal daily protein range for a non-hospitalized patient?
0.8 - 1 g/kg/day
Trissel’s manual is an especially good reference for determining what kind of interaction?
Medication-TPN interactions
What is the normal range for ionized calcium?
4.6 - 5.1 mg/dL
To avoid refeeding syndrome, at what rate should you initiate TPN?
At half of the rate you calculated. In malnourished patients, consider initial rate of a quarter of calculation.
What ion does the secreted H+ bind with in titratable acidity?
Phosphate. Lower capacity because phosphate harder to access.
What is used to treat hyperphosphatemia?
IV calcium
What changes to TPN should be considered in patients with diabetes?
30% of total kcal given as fat, be sure to monitor blood glucose
D5W – maintenance, rehydration, or resuscitation?
Rehydration
Vitamin D deficiency
Ricketts or osteomalacia
How many calories does propofol provide?
1.1 kcal/mL
Under which situations should you choose KPhos for IV replacement over NaPhos?
If K
What value should daily lipid intake not exceed?
2.5 g/kg/day – no more than 60% daily caloric intake
What are the characteristic symptoms of hypervolemic hypotonic hyponatremia?
Edema and weight gain
What is ratio of mEq of Mg to grams of Mg?
8 mEq = 1 gm
What is the end result of carbonic anhydrase inhibitor therapy?
Prevents bicarb reabsorption – urinate it out. Can cause metabolic acidosis or correct metabolic alkalosis.
What amount of phosphate should you give if a patient’s phosphate is
1 mMol/kg
What rate should you not exceed when replacing phosphate?
NMT 7 mMol/hr
How fast should a patient’s sodium deficit be replaced?
1/2 over 1st 8 hours, then next half over next 16 hours
Fluid requirements for infant 0-3 kg
120 mL/kg/day
Does administration of drugs with enteral nutrition tend to increase or decrease bioavailability and pharmacologic effect?
Tends to decrease efficacy – must interrupt continuous feed for a few hours to give meds.
Muscle cramps, weakness, postural dizziness, cellular hypoxia, mental confusion, coma, seizures, CV collapse, and arrhythmias can be symptoms of…
Metabolic alkalosis
GI bicarbonate loss, pancreatic fistulas/biliary drainage, renal bicarbonate loss (RTAs), TPN administration and chronic renal failure can all cause what acid/base disorder?
Non-anion gap metabolic acidosis
Are decreased cardiac output and contractility, hyperkalemia, insulin resistance, inhibited anaerobic glycolysis, and coma signs of acidemia or alkalemia?
Acidemia
What major symptom do we worry about in potassium disorders?
Cardiac arrhythmias or changes in function
How should saline resistant metabolic alkalosis be treated?
Spironolactone (antagonizes mineralcorticoid receptor – decreases H+ secretion), potassium sparing diuretic or KCl supplementation to correct hypokalemia, or decrease dose of mineralcorticoid
Which should come first – electrolyte correction or nutrition support?
Electrolyte correction
What protein should never be added to TPN?
Albumin (high microbial growth potential)
Folic acid deficiency
Anemia, birth defects, esp pregnant women and alcoholics
What is a signature symptom of hyperkalemia?
Peaked T wave
True or false: Albumin responds quickly to changes in nutrition
False – Prealbumin is a better indicator of protein and calorie intake
Caloric intake for infant 6-12 most
90-100 kcal/kg/day
What disorder is characterized by low pH, low pCO2, and low HCO3?
Metabolic acidosis
What needs to be done for patients with hypovolemic hypotonic hyponatremia?
Restore volume deficit. If symptomatic, 3% NaCl first.
What is a normal pCO2?
40
What patients are high risk for refeeding syndrome?
Malnourished patients
What administration frequency of enteral nutrition is best tolerated?
Continuous administration
What are the four systems that regulate acid/base balance?
Buffers, kidneys, lungs, and some liver.
What blood gas do metabolic disorders involve?
Bicarbonate (HCO3-)
What is hepatic regulation of acid/base balance based on?
Urea synthesis because 2 bicarb and 2 ammonium are needed to create urea. An increase in urea synthesis decreases the amount of bicarb.
What are the long term routes of enteral nutrition?
Jejunostomy, gastrostomy, PEG
In asymptomatic hypophosphatemic patients, are there PO products available?
Yes – administer in divided doses
Besides hyperventilation, what other symptoms are associated with respiratory alkalosis?
Lightheadedness, confusion, seizures, tetany, muscle cramps, N/V, and decreased cerebral blood flow
True or false: Most hospitalized patients suffer from acute malnutrition
False – most hospitalized patients are somewhere between acute and chronic malnutrition
What are the short term routes of enteral nutrition?
Nasogastric, nasoenteric, and jejunal tubes
Pyridoxine (Vit B6) deficiency
Mild–mood disorders. Severe – neuropathy/convulsions
If a patient is in severe stress, malnutrition, has large caloric requirements, or will need PN >5 days, what kind of parenteral nutrition should he receive?
Central PN – via central line or PICC (peripherally inserted central catheter – good for 2-6 weeks)
What type of bicarb generation has the highest capacity?
Ammonium excretion/ammoniagenesis – instead of the excreted H+ binding with HCO3 to reabsorb it, it binds with ammonia, so the bicarbonate that was made in the cell is essentially new bicarb that is absorbed into the capillary
Do airway obstruction, reduced CNS stimulation, heart failure, lung failure, and nerve disorders affecting the diaphragm tend to cause respiratory alkalosis or respiratory acidosis?
Respiratory acidosis – due to decreased ability to get rid of CO2
What synthetic hormone is the treatment for isovolemic hypernatremia?
Vasopressin (synthetic ADH)
Where are the chemoreceptors for ventilatory regulation located?
Carotid artery, aorta, medulla
When should you treat metabolic acidosis with bicarb?
If pH < 7.10 - 7.15, hyperkalemia, overdoses, and in cardiac arrest if defibrillation, ventilation, and meds have already been used
What is a normal HCO3-?
24
When should calcium chloride be used?
When administering into central line or during a code
True or false: Once a patient is ready to be discharged, TPN can be discontinued immediately. The patient’s GI tract is functional so he can just switch to food.
False – TPN must be tapered down by 1/2 every 2 hours.
What is the most common cause of pseudohyponatremia?
High proteins/lipids causing increased plasma volume, falsely diluting Na
If PO magnesium cannot be given to a hypomagnesemic patient, how much Mg be administered IV?
0.5 mEq/kg if Mg is 1-2 mg/dL or 1 mEq/kg if Mg is
Which types of patients are more prone to hypercalcemia?
Cancer patients – treatments also more chronic
What type of bicarb generation relies on ATP?
Distal tubular hydrogen ion secretion – H+ is transported into lumen by ATPase and HCO3 freely enters peritubular capillary
What treatment is usually enough to correct hypervolemic hypernatremia?
Stop hypertonic fluids or other cause. Diuretic only if needed.
What is the treatment for saline responsive alkalosis?
Saline or KCl – caution if HF or RF or carbonic anhydrase inhibitors
What acid/base disorder is characterized by increased pH, decreased pCO2, and decreased HCO3?
Respiratory alkalosis
Glucose transporter in brain
GLUT3
What are the two main ways that the kidney regulates acid base balance?
Reabsorbing bicarb and secreting H+
If a patient’s body weight is >150% IBW, what weight should you use?
IBW (permissive underfeeding)
What is a normal anion gap?
3 - 11 mEq/L
What is your goal daily protein range for a mild to moderately stressed patient (medical floor/repletion)?
1 - 1.5 g/kg/day
If a patient has asymptomatic hypokalemia, what should they be given to treat it?
PO potassium – liquid, powder, tablets, etc.
What changes to TPN should be considered in patients with renal disease?
Fluid restriction. If pre-dialysis, give low protein. If receiving dialysis, give standard protein.
