electrolyte management

1. ELECTROLYT
E
IMBALANCE

2. HYPONATREMIA
 Plasma Na < 135mM
 22% of hospitalised patients

5. CLINICAL PRESENTATION
 Symptoms are primarily neurological.
 Early symptoms can include nausea,
headache, and vomiting.
 In chronic hyponatremia, patients suffer from
vomiting, nausea, confusion and seizures,
usually at plasma Na+ concentration <125
mM.
 Even patients who are judged
“asymptomatic” can manifest subtle gait and
cognitive defects that reverse with correction
of hyponatremia; chronic “asymptomatic”
hyponatremia increases the risk of falls and
increases the risk of bony fractures.

6. DIAGNOSTIC EVALUATION
 DETAILED DRUG HISTORY
 VOLUME STATUS
 RADIOLOGIC IMAGING TO RULE
OUT CNS OR PULMONARY
CAUSES
 LAB INVESTIGATIONS

7. LAB INVESTIGATIONS
 SERUM OSMOLALTIY
 BUN and CREATININE
 HYPERKALEMIA
 SERUM GLUCOSE
 URIC ACID
 THYROID/ADRENAL/PITUITARY
FUNCTION
 URINE ELECTROLYTES AND
OSMOLALTIY

8. TREATMENT GOALS
 PRESENCE AND SEVERITY OF
SYMPTOMS DETERMINE THE
URGENCY AND GOALS OF THERAPY
 CHRONIC HYPONATREMIA ARE
MORE PRONE TO ODS IF NA IS
CORRECTED >8-10mM IN 24HRS OR
>18mM IN 48HRS
 RESPONSE TO SALINE OR AVP
ANTAGONISTS CAN BE HIGHLY
UNPREDICTABLE

9.  Na DEFICIT= TBW*(DESIRED-ACTUAL)
 TBW=
0.6(MALES)/0.5(FEMALES)*WEIGHT
 1000ml of 3% NS = 514 mEq of Na
 2 ml of 3% NS = 1mEq of Na
 6.5ml of NS = 1mEq of Na

10. ACUTE
• THE RISE SHOULD BE 4-6mM
• USE OF SUPPLEMENTAL O2 AND
VENTILATORY SUPPORT
• IV LOOP DIURETICS IN
PULMONARY EDEMA
• VAPTANS HAVE NO ROLE

11. CHRONIC
• RATE OF CORRECTION- <10-
12mM IN 24HRS OR <18mM IN
48HRS
• VAPTANS EFFECTIVE IN
HYPERVOLEMIC CONDITIONS
• VAPTANS CAN CAUSE LIVER
INJURY AND SHOULDN’T BE USED
MORE THAN 1-2MONTHS WITH
CLOSE MONITORING

12. HYPERNATREM
IA
• Plasma Na >145mM
• Less common
• Mortality 40-60%

14. CAUSES
• Elderly
• primary or metastatic tumor, occlusion or
ligation of the anterior communicating
artery, trauma, hydrocephalus, and
inflammation.
• Insensible losses of water-fever, exercise,
heat exposure, severe burns, or
mechanical ventilation
• Diarrhea – osmotic diarrhea
• Osmotic diuresis-hyperglycemia, excess
urea, postobstructive diuresis, or mannitol

15. CLINICAL FEATURES
 Altered mental status
 Mild confusion
 Lethargy
 Deep coma
 Parenchymal or subarachnoid
hemorrhages and/or subdural
hematomas;