Hypernatremia resident survival guide

Jump to navigation Jump to search
Hypernatremia
Resident Survival Guide
Overview
Causes
FIRE
Diagnosis
Treatment
Do's
Don'ts


Editor-In-Chief: C. Michael Gibson, M.S., M.D. [1] Associate Editor(s)-in-Chief: Mounika Lakhmalla, MBBS[2]

Overview

Hypernatremia is an electrolyte disturbance consisting of an elevated sodium level in the blood. It is defined as a serum sodium concentration exceeding 145 mEq/L. This is a relatively common problem particularly among young children, older adults, and hospitalized/critically ill who depend upon others to control their water intake.

Causes

Life Threatening Causes

Conditions that may cause death or permanent disability within the next 24 hours

Common Causes

The most common cause of hypernatremia is not an excess of sodium, but a relative deficit of free water in the body. Hypernatremia can be caused by many disease processes and drugs.

  • Primary sodium excess is a rare cause of hypernatremia and can be due to massive salt ingestion or minaralocorticoid excess and administration of hypertonic sodium-containing solutions.
  • Hypernatremia can also occur in cases of primary hypothalamic disease due to impaired thirst (hypodipsia) with or without concurrent diabetes insipidus.

Diagnosis

Shown below is an algorithm summarizing the diagnosis of [[disease name]] according the the [...] guidelines.


 
 
 
 
 
Etiology of
Hypernatremia
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
Urine Osmolality <600
 
Urine Osmolality >600
 
 
If the criteria for Renal loss & GI loss are not satisfied
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
renal loss
 
GI loss
 
 
Insensible losses.

Treatment

 
 
 
 
 
Serum sodium > 145
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
Urine output
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
Low < 200
 
 
 
High
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
High urine osmolality
 
 
 
Urine osmolality
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
Hypotonic fluid loss
GI losses nausea, vomiting, renal losses, diuretics
 
Low
 
High
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 

Replace Both free water deficit as well as Current ongoing fluid losses.

Calculate the fluid deficit, or the water that the patient has already lost to get to their current sodium.
(% Body Water x Body Weight) x [(Current Na – Target Na)/Target Na]
Calculating the ongoing fluid losses which is how much free water the patient is losing daily as you replete.
Precision method is the electrolyte free water clearance:
Urine volume x (1- (Urine Na + Urine K) / serum Na)
Add ‘fluid deficit’ and ‘ongoing fluid losses’ to find the target water intake for the patient.
It is recommended that dividing by 24 hours and giving hourly as oral free water (preferred) or D5W if the patient is unable to drink or does not have an NG tube.
NOTE, large volumes of D5W may cause osmotic diuresis (through hyperglycemia) and worsen renal water losses.


Target rate for correction of hypernatremia: 10-12 mmol/day is a commonly used[1].
A recent study showed no evidence that more rapid correction was associated with greater risk of mortality, cerebral edema, or adverse events[2]

Rate of correction no more than 1mEq/L/h
Replace 1/2 fluid in 24 hrs, other 1/2 in 24-48 hrs
Hypotension - Normal saline, Stable D5W.
 
Negative water
deprivation test
 
Osmotic diuresis
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
Diabetes insipidus
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
DDAVP
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
Increased urine osmolality
 
 
 
 
 
urine osmolality unchanged
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
Central Diabetes Insipidus
 
 
 
 
 
Nephrogenic diabetes Insipidus
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
Treat with Desmopressin &..
 
 
 
 
 
Causes of Nephrogenic DI:Hypercalcemia, hyperkalemia, Lithium ...

Thiazide diuretics in combination with a low salt diet have long been used to treat nephrogenic DI due to lithium.
More recent literature suggests that acetazolamide may also be effective, and may be useful for patients whose nephrogenic DI is refractory to thiazides. (Gordon 2016)

Treat with Thiazide diuretics, Acetazolamide &...
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 

Do's

Don'ts

References

  1. Adrogué HJ, Madias NE (2000). "Hypernatremia". N Engl J Med. 342 (20): 1493–9. doi:10.1056/NEJM200005183422006. PMID 10816188.
  2. Chauhan K, Pattharanitima P, Patel N, Duffy A, Saha A, Chaudhary K; et al. (2019). "Rate of Correction of Hypernatremia and Health Outcomes in Critically Ill Patients". Clin J Am Soc Nephrol. 14 (5): 656–663. doi:10.2215/CJN.10640918. PMC 6500955 Check |pmc= value (help). PMID 30948456.

Template:WikiDoc Sources