Hyponatremia is a low serum sodium level below 135 mEq/L. It can be caused by a decreased total body water, inappropriate antidiuretic hormone secretion, or an inability of the kidneys to excrete diluted urine. Symptoms range from nausea and vomiting to neurological changes like confusion and seizures as water moves into brain cells. Treatment involves fluid restriction and sodium replacement through oral intake or intravenous solutions depending on the severity of low sodium levels. Close monitoring of fluid balance and serum sodium levels is needed to manage the condition and prevent complications.
2. Hyponatremia is a serum sodium level below
135 mEq/L
ETIOLOGY:-
- Decreased total body water (dehydration)
- Syndrome of inappropriate antidiuretic
hormone. It may follow many forms of drug
therapy e.g:- Chemotherapy, phenothiazines,
morphine and barbiturates.
- Inability of kidney to excrete sufficiently
diluted urine.
3. - Hypovolemic hyponatremia:- Renal loss of
sodium from diuretic use, daibetic
glycosuria, aldosterone deficiency, intrinsic
renal disease.
External loss of sodium from vomitting,
diarrhea, increased sweating, burns.
- Euvolemic hyponatremia:- Sodium deficit
result from syndrome of inappropriate
antidiuretic hormone or the continuous
secretion of antidiuretic hormone due to
pain, emotions, medication.
4. - Hypovolemic hyponatremia:- Edematous
disorders resulting in sodium deficits,
congestive heart failure, cirrhosis of liver,
nephrotic syndrome, acute and chronic renal
failure.
- Redistributive hyponatremia:-
Pseudohyponatremia, hyperglycemia,
hyperlipidemia.
RISK FACTORS:-
- Elderly, infants and small children
- Vomitting, diarrhea, cardiac or renal
disorders
5. - Addison’s disease
- Patients on NPO and recieving IV infusion
- Patients on potent diuretics without sodium
replacement
- Excessive perspiration
- Less fluid intake.
- Athletes and outdoor laborers.
7. ↓
(Osmosis)
↓
Water moves into cells
↓
Delayed membrane repolarisation
↓
Cerebral edema
Uncorrected hypovolemic hyponatremia may result
in shock from continued ECF volume loss.
8. - Increased thirst
- Cellular swelling which causes neurologic or
behavioral changes
- GI:- Nausea, vomitting, diarrhea, hyperactive
bowel sounds, abdominal cramps.
- Cardiovascular:- Decrease in diastolic blood
pressure, tachycardia, profound orthostatic
hypotension, weak pulse.
- Pulmonary:- Changes in rate of respiration,
adventitious breathe sounds.
9. - Neurologic:- Headache, apprehension,
lethargy, confusion, slowed problem solving
flat affect, dimnished muscle tone in
extremities, decreased deep tendon reflexes,
weakness and tremor.
- Integumentary:- Dry skin, pale, dry mucus
membranes.
LABORATORY FINDINGS:-
- Serum sodium<135mEq/L
- Urine sodium<40mEq/L
- Serum osmolarity<275mOsm/Kg
10. Sodium is abundant in GI tract, loss of GI
secretions cause sodium loss.
Losses of sodium and water decrease the
circulating fluid volume and may result in
shock like symptoms.
Dilutional hyponatremia with excessive fluid
volume increases circulating fluids.
Due to changes in central nervous system
Fluid overload, congestive heart failure
Diluted body fluids move into brain cells,
affecting both cognition and reflexes,
11. excitable membranes are less responsive to
stimuli.
- Decreased interstitial fluids
- Results in hyonatremia, symptoms become
apparent when the serum sodium is<125
mEq/L.
- Body sodium losses result in decreased
concentration of sodium in body fluids.
MEDICAL MANAGEMENT:-
Intake of fluids will be restricted to allow the
sodium to regain balance.
12. If the serum sodium level falls below
125mEq/L, sodium raplcement is needed.
PHARMACOLOGIC MANAGEMENT:-
- In moderate hyponatremia, 125mEq/L IV
normal saline solution (0.9%Nacl) or RL may
be ordered.
- When the serum sodium level is 115 mEq/L
or less, a concentrated saline solution such
as 3% Nacl is generally indicated.
- Normal saline is administered in conjunction
with diuretic frusemide (Lasix), which
13. Increases urinary sodium loss and therefore
reduces the risk of ECF volume expansion.
Moreover, the urine excreted through
frusemide induced diuresis has much less
sodium than does the ECF, which raises
serum sodium level.
Drug therapy for hyponatremia from
SIADH includes agents that antagonise ADH,
such as demeclocycline and lithium.
DIETARY MANAGEMENT:-
Foods high in sodium are recommended.
Grains, cheeses, meats.
14. Nsg dsis:- Hyponatremia r/t vomitting,
diarrhea, gastric suctioning, burns, SIADH or
surgery.
Expected outcomes:- The nurse will monitor
the client for sodium levels to return to
135mEq/l or above, the reduction of factors
contributing to hyponatremia, fluid and
electrolyte losses and replacement and
symptoms of fluid and sodium imbalance.
Implementation:-
- Check v/s every 4-8 hrs.
15. - Monitor serum sodium and osmolality levels.
(Serum sodium less than 125mEq/L indicates
need for prompt medical care).
- Fluid intake whether oral or IV should include
sodium. If the patient is recieving 3% saline
solution IV, the nurse observes s/s of
hypervolemia eg- dyspnea, chest crackles
and neck vein engorgement.
- The nurse should irrigate NG tubes and
wound sites with normal saline solution to
prevent further sodium losses.
16. - Closely monitor intake and output.
- Raise side rails and keep bed in low position
when nurse is not providing direct care.
- As seizures may develop the patient should
be protected from injury during seizure and
airway should be maintained.