Electrolytes Flashcards
Most K+ is located where in the body? Does this affect replacement frequency?
In the cells; Yes, you may need multiple bolus administrations to bring serum K+ up to normal when in a deficit due to unknown deficit in the tissues
As pH increases, how is K+ affected? pH decrease?
Increase in pH = more K+ into cell (Hypokalemia risk)
Decrease in pH = more K+ into serum (Hyperkalemia risk)
How does low K+ affect insulin? high K+?
Low K+ = inhibition of insulin release
High K+ = increased release of insulin
Hypokalemia severity classification
[K+] <3.5
a. Mild to Moderate = 3.5 to 2.5
b. Severe = <2.5
Digoxin therapy: Less than 3.5 = concern
Signs/Symptoms of hypokalemia
- muscle weakness
- myalgia
- decreased tendon reflex
- cardiac symptoms
- HTN / EKG abnormalities / Arrhythmias
When do you initiate drug therapy of K+?
If patient is symptomatic
If patient has [K+] < 3.0 mEq/L (<3.5 for digoxin pts)
Whats the usual adult dosage for K+ supplementation?
20 to 80 mEq PO QD
Who should we be careful with K+ supplementation? Why?
Diabetics = insulin release issues
ACE-Inhibitor pts = may induce HYPERkalemia
Renal dysfunction = decreased excretion
K+ Infusion rate rules:
<10 mEq/hr does not need telemetry
10 to 20 mEq/hr requires telemetry
Max IV rate of K+ = 20 mEq/hr
Primary Intracellular electrolytes
Potassium
Magnesium
Calcium
Primary Extracellular electrolytes
Sodium
Bicarbonate
Chloride
What electrolyte problem must you correct to reduce K+ wasting?
hypomagnesemia; K+ needs Mg2+ for absorption
Hyperkalemia severity classification
Moderate: [K+] > 5.5 + T wave peak/PR prolongation
Severe: [K] > 7 + Prolonged QRS/VFib
Complete block @ [K+] conc. > 8mEq/L
How do you treat a symptomatic HYPERkalemic patient?
- IV Calcium STAT: 1 g push
- Insulin and GLU: promote increase K+ to cells and prevention of hypoglycemia via increased insulin release
- Loop diuretics to increase excretion
- Kayexelate to increase excretion
- Hemodialysis to excrete excess
Hypomagnesemia Signs/Symptoms
CNS: lethargy, weakness, confusion
CV: V-tach, V-fib, ventricular premature contraction
Treatment for Hypomagnesemia
a. Symptomatic and [Mg] <1
b. [Mg] <1 mg/dL w/o symptoms
c. [Mg] >1 mg/dL w/o symptoms
a. IV Mag Sulfate: 2 gram bolus + 0.5 to 1 mEq/kg/day to replenish stores over 2-5 days
b. . IV Mag Sulfate: No bolus! - continuous infusion
c. Oral Mag Supplement: Mag Oxide 400 to 800 mg QID
Hypermagnesemia Signs/Symptoms
[Mg] > 8.0 mg/dL Absent deep tendon reflexes Muscle weakness Sedative-like effect Vasodilation Diarrhea
Treatment for Hypermagnesemia
Discontinue magnesium treatment
Use Calcium to reverse effects
Give diuretic to promote excretion
Hypocalcemia severity classification
Mild to Moderate = <8.5 to 6.0mg/dL
Severe = Total serum [Ca] <6.0 mg/dL
Hypercalcemia severity classification
Mild to Moderate = >10.5 to 13 mg/dL
Severe = Total serum [Ca] >13 mg/dL
Calcium is 50% bound to what in the plasma? What does this influence?
ALBUMIN
- amount of active calcium
- pH of the blood is raised as more calcium is BOUND
What hormone increases calcium reabsorption to raise levels to normal?
PTH: Parathyroidhormone
What medication is a common cause of elevated calcium levels?
THIAZIDE DIURETICS
Hypercalcemia Signs/Symptoms
[Ca] > 10.5 Constipation, Nausea and Vomiting Others: Confusion lethargy weakness HYPOreflexia Renal chg: polyuria & stones CVD: HTN, heart
Treatment of Hypercalcemia: [Ca] >12 or symptomatic
a. Hydration + mobilization: 0.9% NaCl bolus with LOOP diuretic that reduces calcium reabsorption
b. Calcitonin = inhibits osteoclasts + increased renal excretion
- Aredia/Zometa bisphosphonates
c. Hemodialysis
d. Sensipar = PTH gland receptor
Hypocalcemia Signs/Symptoms
[Ca] = <8.5 mg/dL High albumin levels Acute: Neuromuscular and Cardiac symptoms - Cramping - Spasms (eye twitch) Chronic: confusion, hair loss, psoriasis
Treatment for hypocalcemia
a. Acute, Symptomatic
b. Chronic
a. Ca-gluconate 3gm OR CaCl2 1gm IV push
b. Oral calcium/Vit D supplementation
A patient with end-stage renal disease has high albumin in the plasma. What is the concern with measured calcium levels?
Must correct calculated [Ca] using equation provided to re-assess whether there is a deficit or surplus of [Ca]
Hyperphosphotemia severity classification
Mild = >4.6 to 6.5 mg/dL Moderate = >6.5 to 7 mg/dL Severe = >7.0 mg/dL
Hyperphosphotemia Signs/Symptoms
[P] >4.6 Precipitation with Calcium = deposits in the arteries *Similar to HYPOcalcemia** Neuromuscular and Cardiac symptoms - Cramping - Spasms (eye twitch) Confusion, hair loss, psoriasis
Treatment of Hyperphosphotemia
AVOID PROCESSED FOODS, Renagel
Hypophosphotemia severity classification
Moderate = <2.5 to 1 mg/dL Severe = <1.0 mg/dL
Treatment for hypophosphotemia
Moderate: Oral Supplement
- Neutra-phos K 1.25 g PO BID to TID
Severe: 0.2 mmol/kg over 3 to 12 hours
Where is the majority of sodium located in the body?
Extracellular Fluid
Hyponatremia severity classification
Large, rapid changes = More severe
Mild = < 134 mEq/L
Moderate = <120 mEq/L
Severe = <115 mEq/L
Hyponatremia Signs/Symptoms
Mild: Confusion, headache, agitation, nausea, vomiting
Mod to Sev: Seizures, coma, death
Treatment of Hyponatremia
Limit of 8 to 12 mEq/24 hours (0.33 to 0.5 mEq/hour)
Fluids: Restriction v 0.9% NS v 3% NaCl
What is Euvolemic hypotonic hyponatremia?
Having appropriate hydration but low osmolality and low sodium concentrations in the blood
SIADH
Syndrome of Inappropriate anti-diuretic hormone
- Xs production of ADH
- Xs water reabsorption
Causes: SSRIs/SNRIs + Ecstasy
Treatment: Only if [Na+] < 115 mEq/L
- 3% NaCl to correct deficit
- Chg in diuretic
- Fluid restriction
How do you treat HYPOvolemic hypotonic hypernatremia?
Symptomatic:
Start with 0.9% NS 200 - 300 mL/hour then use D5W (free water) and/or lower NS conc.
No symptoms: Use D5W (free water) and/or lower NS conc. + remove diuretics
Diabetes insipidus may result in which sodium alteration? Which fluid replacement would you use?
ISOvolemic Hypernatremia
Use D5W due to ICF loss = ECF loss
Hypernatremia severity classification
Mild to Moderate = >145 to 160 mEq/L
Severe = >160 mEq/L
Hypernatremia Signs/Symptoms
Mild to Moderate: polyuria and polydypsia
Severe: Neurological distrubances
- Confusion, rigidity, tremor, coma
% body water trend with age
Decreases with age (75-85% in newborns)
% body water trend with increasing body fat
Decreases
For each 1 mEq decrease in serum [K+] below 3.5 mEq/L, the total body K+ deficit is ___ mEq
100-400 mEq
Acidosis effect on K+
Increases serum K+ as H+ is exchanged for K+ in the blood
Alkalosis effect on K+
Decreases serum [K+] as it drives it into cells (in exchange for H+ into the blood)
Insulin/K+ relationship
- Hyperkalemia induces insulin release, which facilitates K+ movement into cells (+ Na/K ATPase activity)
- Hypokalemia inhibits insulin release
Why might diuretics cause hyperglycemia in Type II diabetics?
Hypokalemia (diuretics cause loss of K+) inhibits the release of insulin, putting patient at risk for hyperglycemia
Beta-agonist/K+ relationship (albuterol, epinephrine)
- Increases Na/K ATPase activity, which drives K into cells
2. Increases glycogenolysis, which increases glucose and insulin, drives K+ into cells
Aldosterone/K+ relationship
Promotes K secretion @ distal convoluted tubule and collecting duct (increases Na/K ATPase activity, which keeps Na/water)
CAUSES: inadequate intake Cellular shifting vomiting NG suction Diarrhea Diabetic ketoacidosis
Hypokalemia
Drug-induced: amph B
Laxatives
Steroids
Loop diuretics**
Hypokalemia
Mild-moderate hypokalemia: mEq/L
2.5-3.5 mEq/L
Severe/critical hypokalemia: mEq/L
<2.5 mEq/L
Who are we especially worried about when we see hypokalemia?
Digoxin users
Those with pre-existing arrhythmias
S/S of hypokalemia are not usually seen until [K+] < ____ mEq/L
3 mEq/L
“Patient complaints” of hypokalemia: (<3 mEq/L)
Muscle weakness
Decreased tendon reflex
Myalgia
EKG abnormalities of hypokalemia=
ST depression
Inverted T waves
Elevated U waves
Clinical observations: Cardiac arrhythmias EKG abnormalities Digoxin toxicity HTN
Hypokalemia
Non-symptomatic patient’s [K+]= 3-3.5 mEq/L…treatment?
Non-pharmacologic intervention is OK
Diet switch to higher potassium foods (bananas, meat, broccoli, nuts)
Patient’s [K+] < 3 mEq/L…treatment Y/N?
Yes
Patient is symptomatic of hypokalemia…do you proceed with treatment, Y/N? (Regardless of K lab value?)
Yes
Digoxin user with [K+]< ___ mEq/L warrants treatment.
< 3.5 mEq/L
5 general treatments for hypokalemia
- Oral replacement products
- IV replacement (NPO or moderate-severe deficiency)
- K+ sparing diuretic (for diuretic-induced hypokalemia)
- Correct hypomagnesemia
- Evaluate acid/base balance
Preferred treatment for hypokalemia:
Dose
ADEs
Caution IN
Oral replacement products (KCl, KPO4, K-acetate, K-citrate, K-gluconate)
20-80 mEq daily (for adults)
Tastes like shit, N/V, gas, diarrhea
Caution in diabetics, ACE-inhibitors, renal dysfunction
Treatment for hypokalemia for patients with NPO or symptomatic/severe deficits:
(<2.5 mEq/L)
IV replacement
IV replacement for hypokalemia infusion rate MAX
20 mEq/H (40 for life threatening situations only)
IV replacement for hypokalemia infusion rate with telemetry monitor (ICU)
10-20 mEq/H
IV replacement for hypokalemia infusion rate on non-telemetry wards
≤ 10 mEq/H
For diuretic-induced hypokalemia, which drug treatment could be considered? Who should this NOT be used for (or used with caution)?
K+-sparing diuretics
Diabetics, ACE-inhibitors, renal dysfunction (increased risk for HYPERkalemia)
What is the timeline of monitoring in a stable patient with oral therapy for hypokalemia? For a hospitalized patient with IV therapy?
Monthly…daily/PRN (read the room)
Some causes include... Acute renal failure Blood stored for long periods of time Addison's disease Massive tissue damage Salt substitutes
Hyperkalemia
Drug-induced = K+ sparing diuretics NSAIDs ARBs ACE-inhibitors K+ supplements
Hyperkalemia
Main S/S of hyperkalemia:
CARDIOVASCULAR
Normal K= 3.5-5 mEq/L
Moderate hyperkalemia: > ___ mEq/L
EKG abnormalities=
> 5.5 mEq/L
T waves peak
PR prolongation
Severe hyperkalemia: ___ mEq/L
EKG abnormalities/arrhythmias=
7-8 mEq/L
QRS complex prolongation
V-fib
With [K+] at 8-10 mEq/L, what S/S would you expect?
Complete heart block
Asystole
(BAD, FATAL)
What is pseudohyperkalemia? Treatment?
False hyperkalemia finding due to bad blood sample with traumatized RBCs
List the 8 treatments for hyperkalemia in a symptomatic patient (general!)
- IV calcium chloride
- Insulin +/- glucose
- Albuterol
- Sodium bicarbonate
- Elimination of K+ source
- Loop diuretics
- Polymeric exchange resins (Kayexelate, patiromer, Veltassa, ZS-9)
- Hemodialysis
Why is calcium chloride given to symptomatic patients with hyperkalemia? What is the dose?
Counteracts K’s effect on neuromuscular membranes (protects the heart!)
1 g IV push, repeated 5-10 minutes if no effect
Repeated as needed as effect wears off
Why is insulin given to symptomatic patients with hyperkalemia?
Dose?
Insulin promotes K+ entry into cells
10-20 Units of short-acting insulin
If insulin is being administered to a hyperkalemic patient, should glucose be given also? If yes, why? Dose?
Yes, glucose is added if blood glucose is low or at normal levels to prevent hypoglycemia.
25 g of 50% dextrose solution given over 30 minutes (also stimulates endogenous insulin release!)
What could be given to a hyperkalemic patient exhibiting symptoms and acidosis? Why?
Dose:
Sodium bicarbonate
Promotes K+ entry into cells (acidosis pushes K+ into blood, alkalosis pushes K+ into cells)
50-100 mEq IV push
Should loop diuretics be given to patients with symptomatic hyperkalemia? Why, or why not?
Yes… and no.
They promote renal elimination of K+, but their full effect occurs in 1-2 hours.
Other interventions should be done along with this.
Not suitable for renally impaired patients.
List 3 polymeric exchange resins used for hyperkalemia
- Sodium polystyrene sulfonate (Kayexelate)
- Patiromer (Veltassa)
- Sodium zirconium cyclosilicate (FDA approval pending)
Sodium polystyrene sulfonate (Kayexelate): Indication Dose MOA Onset Contraindication
Hyperkalemia in symptomatic patients 15-60 g SPS powder in water PO or PR Exchanges ~ 1 mEq K for ~1 mEq Na Onset in ~ 1 hour, may repeat Q4H Avoid with GI immobility or dysfunction
Patiromer (Veltassa): Indication Dose Onset ADEs DDIs
Chronic hyperkalemia (symptomatic patient)
8.4, 16.8, 25.2 g packets for suspension
Delayed onset!! (Not for acute hyperkalemia)
ADEs= constipation, hypermagnesemia (5-10%)
DDIs= administer 6 hours apart from other drugs
What is the indication for hemodialysis in a patient with hyperkalemia?
Used for more emergent cases (probably rare though?) or chronic/long-term use (patients already on hemodialysis)
Hyperkalemia treatment in asymptomatic patient:
- Eliminate the K+ source
- Loop diuretics (1-2 hours onset)
- Patiromer (delayed onset, chronic cases)
Calcium normals= 8.5-10.5 mg/dL
What are the critical values (total Ca)?
< 6 mg/dL
> 13 mg/dL
Calcium (free/ionized) critical values
Normals= 1.18-1.30 mmol/L
< 0.9
> 1.6
How is Ca binding to albumin influenced by pH? How much is normally bound to albumin?
Alkalosis increases binding, 50% bound
Corrected Ca=
(4-current albumin)*0.8 + (current Ca)
Causes of hypercalcemia (5)
Hyperparathyroidism Lung/breast cancer Vitamin D toxicity Calcium carbonate toxicity (or just excess administration?) Thiazide diuretics
Patient complaints of hypercalcemia usually do not occur until [Ca2+] > ___ mg/dL
> 13 mg/dL
Confusion, lethargy, weakness, hyporeflexia, polyuria, renal stones
Short QT, V-tach, atherosclerosis, HTN, constipation, N/V
S/S of hypercalcemia
List the treatment options for hypercalcemia (Ca > 12 mg/dL or symptomatic) (7)
- Hydration with 0.9% NaCl given by infusion or bolus, then a loop diuretic
- Calcitonin
- Hemodialysis
- Bisphosphonates (delayed, but prolonged effect)
- Glucocorticoids (in cancer)
- Calcimimetic (Cinacalcet)
- Monoclonal Ab (denosumab)
What is the indication for calcitonin?
Administration?
MOA?
HYPERcalcemia
Intranasal or parenteral (CAUTION: ALLERGY TEST BEFORE)
Inhibits osteoclasts and promotes renal excretion of calcium
Hypercalcemia treatment with a delayed, but prolonged effect
Inhibits osteoclast activity
Bisphosphonates
Hypercalcemia treatment more indicated for cancer/non-emergent cases:
MOA?
Glucocorticoids
Tumor lysis, decrease Ca absorption from GI, inhibit vitamin D synthesis
Hypercalcemia treatment for renal disease or parathyroid cancer patient:
MOA?
Calcimimetic= Cinacalcet (Sensipar)
Binds Ca-sensing receptor on parathyroid gland and increases its sensitivity to Ca (decrease PTH, decreases serum Ca)
Cinacalcet (Sensipar):
Indication
Monitoring
DDIs
Hypercalcemia (renal disease, parathyroid cancer) Monitor PTH/Ca/PO4 weekly until maintenance dose, then every 1-3 months CYP3A4 substrate (erythromycin, -azoles) CYP2D6 inhibitor (tri-cyclics, flecainide)
Indicated for osteoporosis & bone tumors, with an off-label indication for hypercalcemia:
Dose?
MOA?
Cautions?
Monoclonal Ab- denosumab (Prolia, Xyera)
60 mg SQ every 6 months
Binds RANKL, inhibits osteoclasts, inhibits Ca release
Caution with CrCl < 30
Asymptomatic hypercalcemia, Ca < 12 mg/dL treatment:
Observe/monitor
Correct reversible causes
Can be caused by drugs, such as furosemide, bisphosphonates, phenobarbital/phenytoin
Hypomagnesemia
Renal failure
Hypoparathyroid hormone
Hypocalcemia
Hypocalcemia labs:
Normals= 8.5-10.5, 1.18-1.3
Total Ca < 8.5 mg/dL
Ionized serum Ca < 1.1
Acute hypocalcemia S/S:
Neuromuscular & cardiac: Tetany** Paresthesia Cramping Spasms
Chronic hypocalcemia S/S:
CNS & skin:
Confusion
Hair loss
Psoriasis
Treatment for acute hypocalcemia (or symptomatic):
- Treat underlying condition
2. 3 g calcium gluconate OR 1 g calcium chloride by slow vein push (over 10 minutes)
Treatment for non-acute hypocalcemia:
Oral daily supplements of calcium (1-3 g elemental Ca) & vitamin D (0.5-3 mcg 1,25 dihydroxyvitamin D3)
Ca acetate= \_\_% calcium, \_\_ mEq Ca/g Ca carbonate= \_\_\_ % calcium, \_\_ mEq Ca/g Ca \_\_\_= 6.5% calcium, 3.3 mEq Ca/g Ca gluconate = \_\_\_ % calcium, 4.5 mEq Ca/g Ca \_\_\_= 21% calcium, 10.5 mEq Ca/g
25%, 12.5 40%, 20 Glubionate 9%, 4.5 Citrate
Causes: Acute/chronic renal failure Excess administration Hypoparathyroidism Rhabdomyolysis Diabetic ketoacidosis
Hyperphosphatemia
Moderate hyperphosphatemia
Normal= 2.7-4.6 mg/dL
> 6.5 mg/dL
Severe hyperphosphatemia
Normal= 2.6-4.6 mg/dL
> 7 mg/dL
S/S of hyperphosphatemia:
X-ray CaPO4 deposits (Ca x PO4 > 55 at risk)
Hypocalcemia (due to Ca precipitation…tetany, paresthesia, cramping, spasms, confusion, hair loss, psoriasis)
Treatment for severe hyperphosphatemia (> 7 mg/dL):
IV calcium (to form CaPO4 precipitates)
Treatment for mild/moderate hyperphosphatemia
Phosphorous binders Dietary restriction (low protein)
Examples of phosphorus binders.
Indication?
Sevelamer (Renagel)
Lanthanum carbonate (Fosrenal)
Sucroferric oxyhydroxide (Velphoro)
Hyperphosphatemia
Causes: Malnourishment (re-feeding) Acute respiratory alkalosis Diabetic ketoacidosis Antacids
Hypophosphatemia
S/S: hemolysis, leukocyte dysfunction, muscle weakness, rhabdomyolysis, irritability, weakness, seizures, coma
Acute hypophosphatemia
S/S of chronic hypophosphatemia:
Bone pain
Osteomalacia
Treatment for moderate hypophosphatemia (1-2.5 mg/dL):
Oral therapy (Neutra-phos 1.25 g BID-TID or Fleets phospho soda)
Treatment for severe hypophosphatemia (< 1 mg/dL)
IV therapy
0.2 mmol/kg over 3-12 hours
Associated causes are renal disease, SIADH, CHF, cirrhosis
Hyponatremia
Associated causes are renal disease, adrenal disease, diabetes insipidus
Hypernatremia
Mild hyponatremia labs
Normal= 134-145 mEq/L
< 134 mEq/L
Moderate hyponatremia labs
Normal= 134-145 mEq/L
< 120 mEq/L
Critical hyponatremia labs
Normal= 134-145 mEq/L
< 115 mEq/L
S/S: mild- headache, confusion, agitation, N/V, disorientation
Hyponatremia
S/S: moderate-severe- seizures, coma, death
Hyponatremia
Rule for serum Na correcting:
No more than 8-12 mEq/L per 24 H or else there is risk for central pontine myelinolysis
Calculating the sodium deficit in HYPOnatremia:
(Na,desired-Na,current)*(body water)= mEq to replace
% H20: Child Male <70 Male ≥ 70 Female < 70 Female ≥ 70
- 6,
- 6,
- 5,
- 5,
- 45
Once you calculated the Na deficit (mEq to replace), how do you find the infusion rate of 3% NaCl? When to use this fluid?
513 mEq= X Na deficit to replace (mEq)
1000 mL. Y mLs
Y mls/24 hour= infusion rate
Use 3% NaCl when patient is hyponatremic AND euvolemic (or doesn’t need excess fluid)
Once you calculated the Na deficit (mEq to replace), how do you calculate the infusion rate of 0.9% NaCl? When would you use this fluid?
154 mEq = X Na deficit to replace (mEq)
1000 mL. Y mls
Y mls/24 hours= infusion rate
Use 0.9% NaCl when patient is hyponatremic and hypovolemic (or needs more fluids)
Calculate the change in [Na] if 1 L of 3% NaCl was administered:
UNITS?
*(IV,na-S'na)/(BW + IV,vol)= mEq/L* IV,na= [Na] of infusion, 513 mEq/L S'na= initial [Na] of patient BW= body water IV, vol= 1 L
Calculate the change of [Na] if 1 L of 0.9% NaCl was administered:
(IV,na-S'na)/(BW + IV,vol)= mEq/L IV,na= [Na] content of infusion, 154 mEq/L f S'na= initial [Na] of patient BW= body water IV, vol= 1 L
How do you calculate the infusion rate after finding the change in [Na] after 1 L of fluid administered?
Solved X Na change mEq= desired change in [Na]
1000 mls. Y mL
Y ml/24= infusion rate
Hypotonic hyponatremia (serum Osm < 280 mOsm): euvolemia causes
Water intoxication (either too much intake or decreased excretion) SIADH (too much ADH, too much water reabsorption)
Condition caused by SSRIs and SNRIs, MDMA, and ecstasy
SIADH (syndrome of inappropriate anti-diuretic hormone) with too much production of ADH
Euvolemic hypotonic hyponatremia
Condition caused by NSAIDS, hypoglycemic agents (1st gen.), carbamazepine, cyclophosphamide
SIADH (syndrome of inappropriate anti-diuretic hormone) with increased renal sensitivity
Euvolemic hypotonic hyponatremia
Treatment of ACUTE euvolemic hyponatremia (hypotonic):
Na levels < ____ mEq/L and/or symptomatic
< 115 mEq/L
3% NaCl infusion
+/- diuretics
Fluid restriction (not ideal)
Treatment of non-acute euvolemic hyponatremia (hypotonic):
Na levels > ___ mEq/L and/or asymptomatic
> 115 mEq/L Fluid restriction Chronic therapy OF.... Diuretics Salt or urea tabs Demeclocycline (SIADH go-to) ADH receptor antagonist (conivaptan IV, tolvaptin oral)
Hypervolemic hypotonic hyponatremia: EABV Conditions Water relation to Na Kidney response
Decreased EABV
CHF, cirrhosis, nephrosis
Water»_space; Na
Kidney senses volume depletion (edema), so aldosterone levels are increased
Treatment of hypervolemic hyponatremia (hypotonic, 4 steps):
- Treat underlying disease
- Diuretics (spironolactone would counter aldosterone increase)
- Increase oncotic pressure (help with edema)
- Fluid restriction
Hypovolemic hyponatremia (hypotonic) has high urine osmolarities. If sodium content in urine is HIGH, this indicates:
Kidneys are the problem (renal losses)
Diuretics
Adrenal insufficiency
Hypovolemic hyponatremia (hypotonic) has high urine osmolarities. If sodium content in urine is LOW, this indicates:
Kidneys are functioning properly
GI/skin/lung loss
Hypovolemic hyponatremia (hypotonic) treatment
Volume replacement with 0.9% NaCl
Loss of water Associated causes: Diabetes insipidus Skin losses Osmotic diuresis Polydipsia
Isovolemic HYPERnatremia
Associated causes: sodium overload, mineralcorticoid excess
Hypervolemic HYPERnatremia
Associated causes: renal loss, adrenal, GI/skin/lung loss
Water loss»_space; Na loss
Exercise, infection
Hypovolemic HYPERnatremia (dehydation)
Hypernatremia labs (+ critical)
> 145 mEq/L
> 160 mEq/L (CRITICAL)
Mild-moderate hypernatremia S/S:
Polyuria, polydipsia, thirsty
Severe hypernatremia S/S
*Neurologic* Confusion Rigidity Tremors Coma Stupor
Calculate the water deficit in a hypernatremic patient:
Variables?
Generally, what fluid is used?
Water deficit= TBW,current * [(S’na/S2na)-1]
TBW, current= current weight * %h20
S’na= current serum Na
S2na= desired [Na]
D5W
Hypernatremia case:
Water losses in ECF=ICF
Usually asymptomatic
Isovolemic (most common)
Diabetes insipidis is associated with which type of hypernatremia?
Isovolemic
Diabetes insipidis with 3-15 L urine/day
Central DI (decreased ADH production)
DI with 3-4 L urine/day
Nephrogenic DI (decreased renal sensitivity)
These meds are associated with \_\_\_. Aminoglycosides Lithium Glyburide Colchicine Amph B Cisplatin Demeclocycline Methoxyflurane
Diabetes insipidis (isovolemic hypernatremia)
Treatment of isovolemic hypernatremia:
- Replace water deficit with D5W
- central DI maintenance= desmopressin
- nephrogenic DI maintenance= NSAIDS, thiazides
Water and sodium excess treatment
(Hypervolemic hypernatremia)
- Replace deficit with D5W (or lesser concentration of NaCl, or combination)
- Loop diuretic to remove excess Na and water
- Hemodialysis if renal failure
Water loss»_space; Na loss
Symptomatic treatment:
(Hypovolemic hypernatremia)
200-300 mL/H of 0.9% NaCl
THEN replace water deficit with D5W (or less conc. Of NaCl or combo)
Water loss»_space; Na loss
Asymptomatic treatment:
(Hypovolemic hypernatremia)
D5W to replace water deficit (or less conc. NaCl or combo)