Fluids and Electrolytes Part 2 Flashcards
Neurological symptoms of hyponatremia: (10)
- N&V
- visual disturbances
- depressed consciousness
- agitation
- confusion
- coma
- seizures
- muscle cramps
- weakness
- myoclonus
If Na < 123 mEq/L, then ____ ___ may result.
If Na < 100, then ___ ____ may result.
cerebral edema
cardiac symptoms
_____ _____ can cause pulmonary edema, HTN, and heart failure.
Hypervolemic hyponatremia
For _____, decrease MAC!
hyponatremia
Treatment for hyponatremia: (3)
- water restriction
- loop diuretic in case of water overload
- hypertonic saline in the case of severe hyponatremia with neuro symptoms
Correct Na deficits very SLOWLY!!!!
Optimal rate of correction is ___-__mmol/L/hr until Na= 125 mEq/L, then proceed slower.
Replace half of the deficit in the first 8 hrs, and the rest over 1-3 days. Monitor sodium levels every 1-2 hrs.
0.6-1
Dose of Na (mEq) for hyponatremia:
(kg x (140-[Na]) ) x 0.6
Correct Na slowly because may cause ____ ___ ___
central pontine myelinolysis
Symptoms include: acute para- or quadraparesis, dysphagia, dysarthria, diplopia, loss of consciousness, and other neurological symptoms associated with brainstem damage.
An increase in ECF [Na] (above 145 mEq/L) which may be accompanied by the presence of low, normal, or high total-body Na content is called _____.
Major cause is:
hypernatremia
lack of fluid replacement
Signs of hypernatremia: (3)
- Intense thirst (unless malfunctioning thirst mechanism)
- Lethargy, mental status changes coma and convulsions.
- Shock, peripheral edema, myoclonus, ascites, muscle tremor, hyperactive reflexes, pleural effusion, expanded intravascular fluid volume
Treatment of hypernatremia:
- diuretics
- hypotonic crystalloids restore normal osmolality and volume
Hypernatremia______the MAC of our anesthetics
increases
Potassium is the most abundant intracellular fluid cation. which maintains membrane potential. True or false?
true
What keeps K in check? (4)
- kidneys
- insulin (big factor)
- hormones
- HCO3
Increase in pH results in _____ in K and vice-versa.
decrease
______ HCO3 decreases K. Hyperventilation produces the same effect.
Increased
Beta2 adrenergic agonists ______ K indirectly due to ___ changes.
decrease
pH
Hypokalemia is present when K < ___ mEq/L
3.5
Causes of hypokalemia include: (4)
- inadequate intake
- excess renal loss
- GI losses
- ECF to ICF shift–such as beta agonist, vitamin b12, insulin
Inadequate intake of K resulting in hypokalemia results from: (4)
- anorexia
- starvation
- alcoholism
- hyperaldosteronism
Hypokalemia from excess renal loss results from: (6)
- diuresis
- chronic metabolic alkalosis
- PCN
- Nafcillin
- renal tubular acidosis
- hypomagnesium
Vomiting and diarrhea can result in hyperkalemia. True or false?
false
hypokalemia
ECF to ICF shifts can be caused by: (6)
- Beta 2 agonist
- acute alkalosis
- insulin
- vitamin B12 therapy
- lithium overdose
- hyperventilation
In the range of 2-2.5 mEq/L, hypokalemia can cause: (5)
- muscle weakness
- arrythmias
- ST depression
- T wave depression
- appearance of a U wave
The changes do not correlate with the severity of Potassium depletion. Dysrrhythmias include a-fib and PVC’s.
Another cause of _____is stress induced by surgery. The increased catecholamine activity causes hypokalemia due to ____ action.
hypokalemia
beta2
If potassium is below _____, treat with IV___.
2.6
KCl
KCl must be diluted in NS (____ mL) and should not be infused faster than ____mEq/hr in a peripheral IV, and ___mEq/hr through a CVL. Monitor the EKG continuously
250
10
20
Hyperkalemia indicated when > ___mEq/L
5.3
Causes of hyperkalemia: (4)
- pseudohyperkalemia
- altered interal K balance
- drugs
- altered external K balance
What causes pseudohyperkalemia? (2)
sample lysis
technical issues
KNOW:
What causes internal K balance changes? (4)
- acidosis
- insulin deficiency
- MH (malignant hyperthermia)
- cell necrosis
What can succinylcholine, digitalis, non-selective B-blockers,** _______**, and spironolactone cause?
ACE-inhibitors
cause hyperkalemia
Decreased excretion from renal disease, transfusions, and hypoaldosterone can cause altered internal/external K balance resulting in this.
external
hyperkalemia
Signs and symptoms of hyperkalemia:
6-7 mEq/L –>
10-12 mEq/L –>
muscle weakness
peaked T waves and long PR interval
wide QRS, ventricular fibrillation and asystole
Treatment for hyperkalemia is determined by presence of ECG changes. Stabilize heart with IV _____.
Redistribute potassium into cells by IV glucose and insulin, (amp D50 + ____ units Insulin- lowers levels within 10 min and lasts 4-6 hours.
calcium
10
What are other treatments for hyperkalemia? (8)
- bicarb
- hyperventilation
- dialysis
- diuretics
- B agonists
- aldosterone
- agonists
- kayexelate
What is responsible for endocrine and exocrine secretions, cell growth, transport and secretion of fluids and electrolytes, and muscle contractions?
calcium
Calcium is controlled by: (2)
PTH
calcitonin
Calcium is a coagulation factor. True or false?
Calcitonin tones down calcium. True or false?
Blood products _______ Ca values.
true
true
decreases
Calcium exists in the body in 3 forms:
- bound to protein (40%)
- ionized, physiologically active (50%)
- nonionized chelated with anions: phosphate, sulfate, citrate (10%)
Ionized calcium does not vary with the albumin level, and therefore it is useful to measure the ionized calcium level when the serum albumin is not within normal ranges, or when a calcium disorder is suspected despite a normal total calcium level. True or false?
true
Calcium levels must be adjusted for low albumin.
If Albumin is low, then the adjusted calcium value is lower than the measured serum calcium value. True or false?
false
higher than
PTH causes increased calcium reabsorption in the kidney and decreased excretion. It also causes bone resorption, therefore increasing calcium. True or false?
true
Hypocalcemia
calcium < ____mg/dL (or 2.2-2.6 mmol) or
ionized calcium levels < _____mmol/L.
- 5
- 1-1.4
What are the causes of hypocalcemia? (4)
- low PTH
- ineffective PTH
- low albumin
- iatragenic in OR
What causes low PTH?
hypoparathyroidism
What may cause ineffective PTH?
lack of vit. D
What may cause low albumin resulting in low Ca? (2)
critical illness
liver disease
What may cause iatragenically low Ca in the OR? (3)
acute hyperventilation
infusion of blood products
parathyroid/thyroidectomy
Decrease in Ca is observed when blood is transfused because:
citrate binds to calcium
These symptoms describe what?
The prognosis is overall poor. While some patients die, most survive and of the survivors, approximately one-third recover; one-third are disabled but are able to live independently; one-third are severely disabled.[11] Permanent disabilities range from minor tremors and ataxia to signs of severe brain damage, such as spastic quadriparesis and locked-in syndrome. Some improvements may be seen over the course of the first several months after the condition stabilizes.
central pontine myelinolysis from giving Na too fast
Acute severe ___________ causes an osmotic shift of water from the cells, leading to shrinkage of the brain and tearing of meningeal vessels and IC hemorrhage.
hypernatremia (as with Na replacement for hypoNa)
What are EKG changes for hyperkalemia?
peaked t waves
