WikEM - User contributions [en]

Hyponatremia

2015-03-07T14:27:27Z

Sukhsingh927: /* Hypervolemic */

==Background==
[[File:Hyponatremia.png|thumb|Algorithm for Hyponatremia]]
*Defined as sodium concentration <135meq/L
*Patients often not symptomatic until <120meq/L although this level varies by patients and may be higher if the change occurred abruptly<ref>Spasovski G. et al. Clinical practice guideline on diagnosis and treatment of hyponatraemia. Nephrol Dial Transplant. 2014</ref>

==Clinical Features==
*[[Nausea and Vomiting]]
*Anorexia
*Muscle cramps
*[[AMS]]
*[[Seizure]] (esp if Na < 113)
*Coma
*Rapid correction can cause [[CHF]] & CPM ([[AMS]], dysphagia, dysarthria, paresis)

==Diagnosis==
*Must determine volume status and calculated osm
**In true hyponatremia the osm is reduced

===Work-Up===
Prior to giving treatment

*Urine
**UA
**Urine electrolytes
**Urine urea
**urine uric acid
**urine osmolality
**urine creatinine
*Serum
**Chemistry
**Serum osmolality
**Uric acid
**TSH
**Cortisol

==Types and Causes==
*Often described in terms of tonicity and volume status of the patient <ref>Understanding Lab Testing for Hyponatremia. Clin J Am Soc Nephrol 2008;3:1175</ref>
===Hypertonic Hyponatremia ===
*Defined as osmolarity > 295mmol/L with the following causes:
#[[Hyperglycemia]]
#*Traditional teaching: [Na+] decreases by 1.6-1.8mEq/L for each 100mg/dL increase in glucose over 100mg/dL
#*2.4mEq/L may be a more accurate correction factor (Hillier 1999)
#[[Mannitol]] excess

===Isotonic (pseudo) hyponatremia===
*Defined as osmolarity > 275-295mmol/L. Often referred to as pseudo hyponatremia because the elevated lipids or proteins interfere with the laboratory sodium reading. The following are common causes:
#Hyperlipidemia
#Hyperproteinemia

===Hypotonic Hyponatremia===
*Defined as an osmolarity < 275 mmol/L and categorized as [[Hyponatremia#Hypovolemic|hypovolemic]], [[Hyponatremia#Hypervolemic|hypervolemic]] or [[Hyponatremia#Euvolemic|euvolemic]]

====Hypovolemic====
#Renal Causes
##Thiazide diuretic use
##Na-wasting nephroathy (RTA, CRF)
##Osmotic diuresis (glucose, urea)
##Aldosterone deficiency
#Extra-renal Causes
##GI loss
##3rd space loss
##*Burns
##*Pancreatitis
##*Peritonitis
====Hypervolemic====
#Urinary Na >20
#*Renal failure
#Urinary Na <20
#*Nephrotic Syndrome
#*Cirrhosis
#*CHF

====Euvolemic====
#SIADH
#*urine sodium is greater than 20-40 mEq/L
#Pain, stress, nausea
#[[Hypothyroidism]]
#Drugs<ref>Review of Drug-Induced Hyponatremia. Am J Kidney Dis 2008;52:144</ref>
#*NSAIDs, sulfonylureas
#H<sub>2</sub>0 intoxication
#Glucocorticoid deficiency

==Treatment==
===Hypertonic hyponatremia===
*Correct underlying disorder which is often hyperglycemia<ref name="treatment">Schrier RW, Bansal S. Diagnosis and management of hyponatremia in acute illness. Curr Opin Crit Care 2008;14:627-34</ref>
*Often volume depleted due to osmotic diuresis and normal saline provides adequate volume repletion
===Isotonic (pseudo) hyponatremia===
*No treatment needed <ref name="treatment"></ref>
===Hypotonic hyponatremia===
#Hypovolemic
#*Give NS but be cautious of total daily repletion of Na so you avoid causing central pontine demylinosis
#Euvolemic<ref name="treatment"></ref>
#*Water restrict
#*Treat underlying cause
#Hypervolemic
#*Water restriction
#*Diuresis
#*Treat underlying cause

===Na Therapy===
*Max correction 10mEq/L in 24hr (avoids central pontine demylinosis)

{|class="wikitable"
|+Sodium Containing fluid Concentrations
| align="center" style="background:#f0f0f0;"|'''Fluid type'''
| align="center" style="background:#f0f0f0;"|'''Sodium Concentration'''
|-
| 1/2 Normal Saline||77 mEq/L
|-
| Normal Saline||154 mEq/L
|-
| Lactated Ringers||130 mEq/L
|-
| 3% Saline||513 mEq/L
|}

====Asymptomatic====
*Step 1: Calculate total body water<ref>The hyponatremia formulas do not work so well (Clin J Am Soc Nephrol 2007;2:1110 and Nephrol Dial Transplant 2006;21:1564)</ref>
**TBW(kg) = Wt(kg) x 0.6 = [Wt(lb) x 0.45] x 0.6 = Wt(lb) x 0.27
*Step 2: Calculate mEq deficit
**(Desired Na - Measured Na) ~ must be ≤ 10
*Step 3: Calculate NS rate to be given over 24hr
**NS rate (cc/hr) = TBW x mEq deficit x 0.27
***If using 3% NS (to avoid volume overload) divide above rate by 3.33

====Symptomatic====
{{Symptomatic Hyponatremia Treatment}}
*Fluid restrict

==Disposition==
*Admit if Na <125

==See Also==
*[[Electrolyte Abnormalities (Main)]]

==Sources ==
<references/>

#Hillier TA, Abbott RD, Barrett EJ. Hyponatremia: evaluating the correction
factor for hyperglycemia. Am J Med. 1999 Apr;106(4):399-403. PubMed PMID:
10225241.[[Category:FEN]]

Hyponatremia

2015-03-07T14:26:36Z

Sukhsingh927: /* Hypervolemic */

==Background==
[[File:Hyponatremia.png|thumb|Algorithm for Hyponatremia]]
*Defined as sodium concentration <135meq/L
*Patients often not symptomatic until <120meq/L although this level varies by patients and may be higher if the change occurred abruptly<ref>Spasovski G. et al. Clinical practice guideline on diagnosis and treatment of hyponatraemia. Nephrol Dial Transplant. 2014</ref>

==Clinical Features==
*[[Nausea and Vomiting]]
*Anorexia
*Muscle cramps
*[[AMS]]
*[[Seizure]] (esp if Na < 113)
*Coma
*Rapid correction can cause [[CHF]] & CPM ([[AMS]], dysphagia, dysarthria, paresis)

==Diagnosis==
*Must determine volume status and calculated osm
**In true hyponatremia the osm is reduced

===Work-Up===
Prior to giving treatment

*Urine
**UA
**Urine electrolytes
**Urine urea
**urine uric acid
**urine osmolality
**urine creatinine
*Serum
**Chemistry
**Serum osmolality
**Uric acid
**TSH
**Cortisol

==Types and Causes==
*Often described in terms of tonicity and volume status of the patient <ref>Understanding Lab Testing for Hyponatremia. Clin J Am Soc Nephrol 2008;3:1175</ref>
===Hypertonic Hyponatremia ===
*Defined as osmolarity > 295mmol/L with the following causes:
#[[Hyperglycemia]]
#*Traditional teaching: [Na+] decreases by 1.6-1.8mEq/L for each 100mg/dL increase in glucose over 100mg/dL
#*2.4mEq/L may be a more accurate correction factor (Hillier 1999)
#[[Mannitol]] excess

===Isotonic (pseudo) hyponatremia===
*Defined as osmolarity > 275-295mmol/L. Often referred to as pseudo hyponatremia because the elevated lipids or proteins interfere with the laboratory sodium reading. The following are common causes:
#Hyperlipidemia
#Hyperproteinemia

===Hypotonic Hyponatremia===
*Defined as an osmolarity < 275 mmol/L and categorized as [[Hyponatremia#Hypovolemic|hypovolemic]], [[Hyponatremia#Hypervolemic|hypervolemic]] or [[Hyponatremia#Euvolemic|euvolemic]]

====Hypovolemic====
#Renal Causes
##Thiazide diuretic use
##Na-wasting nephroathy (RTA, CRF)
##Osmotic diuresis (glucose, urea)
##Aldosterone deficiency
#Extra-renal Causes
##GI loss
##3rd space loss
##*Burns
##*Pancreatitis
##*Peritonitis
====Hypervolemic====
#[[Urinary Na >20]]
#*Renal failure
#[[Urinary Na <20]]
#*[[Nephrotic Syndrome]]
#*[[Cirrhosis]]
#*[[CHF]]

====Euvolemic====
#SIADH
#*urine sodium is greater than 20-40 mEq/L
#Pain, stress, nausea
#[[Hypothyroidism]]
#Drugs<ref>Review of Drug-Induced Hyponatremia. Am J Kidney Dis 2008;52:144</ref>
#*NSAIDs, sulfonylureas
#H<sub>2</sub>0 intoxication
#Glucocorticoid deficiency

==Treatment==
===Hypertonic hyponatremia===
*Correct underlying disorder which is often hyperglycemia<ref name="treatment">Schrier RW, Bansal S. Diagnosis and management of hyponatremia in acute illness. Curr Opin Crit Care 2008;14:627-34</ref>
*Often volume depleted due to osmotic diuresis and normal saline provides adequate volume repletion
===Isotonic (pseudo) hyponatremia===
*No treatment needed <ref name="treatment"></ref>
===Hypotonic hyponatremia===
#Hypovolemic
#*Give NS but be cautious of total daily repletion of Na so you avoid causing central pontine demylinosis
#Euvolemic<ref name="treatment"></ref>
#*Water restrict
#*Treat underlying cause
#Hypervolemic
#*Water restriction
#*Diuresis
#*Treat underlying cause

===Na Therapy===
*Max correction 10mEq/L in 24hr (avoids central pontine demylinosis)

{|class="wikitable"
|+Sodium Containing fluid Concentrations
| align="center" style="background:#f0f0f0;"|'''Fluid type'''
| align="center" style="background:#f0f0f0;"|'''Sodium Concentration'''
|-
| 1/2 Normal Saline||77 mEq/L
|-
| Normal Saline||154 mEq/L
|-
| Lactated Ringers||130 mEq/L
|-
| 3% Saline||513 mEq/L
|}

====Asymptomatic====
*Step 1: Calculate total body water<ref>The hyponatremia formulas do not work so well (Clin J Am Soc Nephrol 2007;2:1110 and Nephrol Dial Transplant 2006;21:1564)</ref>
**TBW(kg) = Wt(kg) x 0.6 = [Wt(lb) x 0.45] x 0.6 = Wt(lb) x 0.27
*Step 2: Calculate mEq deficit
**(Desired Na - Measured Na) ~ must be ≤ 10
*Step 3: Calculate NS rate to be given over 24hr
**NS rate (cc/hr) = TBW x mEq deficit x 0.27
***If using 3% NS (to avoid volume overload) divide above rate by 3.33

====Symptomatic====
{{Symptomatic Hyponatremia Treatment}}
*Fluid restrict

==Disposition==
*Admit if Na <125

==See Also==
*[[Electrolyte Abnormalities (Main)]]

==Sources ==
<references/>

#Hillier TA, Abbott RD, Barrett EJ. Hyponatremia: evaluating the correction
factor for hyperglycemia. Am J Med. 1999 Apr;106(4):399-403. PubMed PMID:
10225241.[[Category:FEN]]

User:Sukhsingh927

2013-09-30T04:40:56Z

Sukhsingh927:

'''Sukhdeep Singh, MD'''

Emergency Medicine, PGY-1

Baystate Medical Center/Tufts University

sukhsingh927@gmail.com

User:Sukhsingh927

2013-09-30T04:34:30Z

Sukhsingh927:

Tufts/Baystate Medical Center C/O 2016

User:Sukhsingh927

2013-09-30T04:34:09Z

Sukhsingh927: Created page with "UC Davis SOM C/O 2013 Tufts/Baystate Medical Center C/O 2016"

UC Davis SOM C/O 2013
Tufts/Baystate Medical Center C/O 2016

Hyponatremia

2013-09-30T03:40:57Z

Sukhsingh927: Added the fact that 3% NS (513 meq/L of Na), given as a bolus of 100ml, will raise your Na by ~2 meq/L.

==Background==
*Urine Na only useful before beginning tx
*Low = <135meq/L
*Symptomatic = <120meq/L (may be higher if occurs abruptly)

==Clinical Features==
*N/V
*Anorexia
*Muscle cramps
*AMS
*Seizure (esp if Na < 113)
*Coma
*Rapid correction can cause CHF & CPM (AMS, dysphagia, dysarthria, paresis)

==Diagnosis==
*Must determine volume status and calculated osm
**In true hyponatremia the osm is reduced

===Work-Up===
Prior to giving treatment

#Urine
##UA
##Urine electrolytes
##Urine urea
##urine uric acid
##urine osmolality
##urine creatinine
#Serum
##Chemistry
##Serum osmolality
##Uric acid
##TSH
##Cortisol

==DDX==
#Hypertonic hyponatremia (osm > 295)
##Hyperglycemia
###[Na+] decreases by 1.6-1.8mEq/L for each 100mg/dL increase in glucose
##Mannitol excess
#Isotonic (pseudo) hyponatremia (osm 275-295)
##Hyperlipidemia
##Hyperproteinemia
#Hypotonic hyponatremia (osm < 275)
##Hypovolemic
###Renal
####Thiazide diuretic use
####Na-wasting nephroathy (RTA, CRF)
####Osmotic diuresis (glucose, urea)
####Aldosterone deficiency
###Extra-renal
####GI loss
####3rd space loss
#####Burns
#####Pancreatitis
#####Peritonitis
##Hypervolemic
###Urinary Na > 20
####Renal failure
###Urinary Na < 20
####CHF
####Nephrotic syndrome
####Cirrhosis
##Euvolemic (urine Na usually > 20)
###SIADH
####Pain, stress, nausea
###Hypothyroidism
###Drugs
####NSAIDs, sulfonylureas
###H20 intoxication
###Glucocorticoid deficiency

==Treatment==
*1. Hypertonic hyponatremia
**Correct underlying disorder
**Often volume depleted (give NS)
*2. Isotonic (pseudo) hyponatremia
**No tx needed
*3. Hypotonic hyponatremia
**A. Hypovolemic
***Give NS (see below)
**B. Euvolemic
***Water restrict
***Treat underlying cause
**C. Hypervolemic
***Water restriction
***Diuresis
***Treat underlying cause

===Na Therapy===
*Max correction 10mEq/L in 24hr (avoids CPM)
*NS = 154 meq/L
*3% NS = 513 meq/L
*each 100 ml will raise sodium by ~2 mmol/l
====Asymptomatic====
*Step 1: Calculate total body water
**TBW = Wt(kg) x 0.6
*Step 2: Calculate mEq deficit
**(Desired Na - Measured Na) ~ must be ≤ 10
*Step 3: Calculate NS rate to be given over 24hr
**NS rate (cc/hr) = TBW x mEq deficit x 0.27
***If using 3% NS (to avoid volume overload) divide above rate by 3.33

====Symptomatic====
*3% NS 100cc bolus over 10min; repeat after 10min x1 if no improvement
**Each 100 ml will raise sodium by ~2 mmol/l
*Fluid restrict

==Disposition==
*Admit if Na <125

==Source ==
*Tintinalli
*Pontine and extrapontine myelinoslysis: a neurologic disorder following rapid correction of hyponatremia Medicine/ 1993;72(6):359-373
*emcrit.org (http://emcrit.org/podcasts/hyponatremia/)
*Review by Schrier (Curr Opin Crit Care 2008;14:627)
*Review of Drug-Induced Hyponatremia (Am J Kidney Dis 2008;52:144)
*Understanding Lab Testing for Hyponatremia (Clin J Am Soc Nephrol 2008;3:1175)
*The hyponatremia formulas do not work so well (Clin J Am Soc Nephrol 2007;2:1110 and Nephrol Dial Transplant 2006;21:1564)

[[Category:FEN]]

Hyponatremia

2013-09-30T03:36:28Z

Sukhsingh927: /* Symptomatic */

==Background==
*Urine Na only useful before beginning tx
*Low = <135meq/L
*Symptomatic = <120meq/L (may be higher if occurs abruptly)

==Clinical Features==
*N/V
*Anorexia
*Muscle cramps
*AMS
*Seizure (esp if Na < 113)
*Coma
*Rapid correction can cause CHF & CPM (AMS, dysphagia, dysarthria, paresis)

==Diagnosis==
*Must determine volume status and calculated osm
**In true hyponatremia the osm is reduced

===Work-Up===
Prior to giving treatment

#Urine
##UA
##Urine electrolytes
##Urine urea
##urine uric acid
##urine osmolality
##urine creatinine
#Serum
##Chemistry
##Serum osmolality
##Uric acid
##TSH
##Cortisol

==DDX==
#Hypertonic hyponatremia (osm > 295)
##Hyperglycemia
###[Na+] decreases by 1.6-1.8mEq/L for each 100mg/dL increase in glucose
##Mannitol excess
#Isotonic (pseudo) hyponatremia (osm 275-295)
##Hyperlipidemia
##Hyperproteinemia
#Hypotonic hyponatremia (osm < 275)
##Hypovolemic
###Renal
####Thiazide diuretic use
####Na-wasting nephroathy (RTA, CRF)
####Osmotic diuresis (glucose, urea)
####Aldosterone deficiency
###Extra-renal
####GI loss
####3rd space loss
#####Burns
#####Pancreatitis
#####Peritonitis
##Hypervolemic
###Urinary Na > 20
####Renal failure
###Urinary Na < 20
####CHF
####Nephrotic syndrome
####Cirrhosis
##Euvolemic (urine Na usually > 20)
###SIADH
####Pain, stress, nausea
###Hypothyroidism
###Drugs
####NSAIDs, sulfonylureas
###H20 intoxication
###Glucocorticoid deficiency

==Treatment==
*1. Hypertonic hyponatremia
**Correct underlying disorder
**Often volume depleted (give NS)
*2. Isotonic (pseudo) hyponatremia
**No tx needed
*3. Hypotonic hyponatremia
**A. Hypovolemic
***Give NS (see below)
**B. Euvolemic
***Water restrict
***Treat underlying cause
**C. Hypervolemic
***Water restriction
***Diuresis
***Treat underlying cause

===Na Therapy===
*Max correction 10mEq/L in 24hr (avoids CPM)
*NS = 154 meq/L
*3% NS = 513 meq/L
====Asymptomatic====
*Step 1: Calculate total body water
**TBW = Wt(kg) x 0.6
*Step 2: Calculate mEq deficit
**(Desired Na - Measured Na) ~ must be ≤ 10
*Step 3: Calculate NS rate to be given over 24hr
**NS rate (cc/hr) = TBW x mEq deficit x 0.27
***If using 3% NS (to avoid volume overload) divide above rate by 3.33

====Symptomatic====
*3% NS 100cc bolus over 10min; repeat after 10min x1 if no improvement
**Each 100 ml will raise sodium by ~2 mmol/l
*Fluid restrict

==Disposition==
*Admit if Na <125

==Source ==
*Tintinalli
*Pontine and extrapontine myelinoslysis: a neurologic disorder following rapid correction of hyponatremia Medicine/ 1993;72(6):359-373
*emcrit.org (http://emcrit.org/podcasts/hyponatremia/)
*Review by Schrier (Curr Opin Crit Care 2008;14:627)
*Review of Drug-Induced Hyponatremia (Am J Kidney Dis 2008;52:144)
*Understanding Lab Testing for Hyponatremia (Clin J Am Soc Nephrol 2008;3:1175)
*The hyponatremia formulas do not work so well (Clin J Am Soc Nephrol 2007;2:1110 and Nephrol Dial Transplant 2006;21:1564)

[[Category:FEN]]