Ver el código de «Lithium toxicity»

==Background==
*Toxicity most often involves a drug-drug interaction or decreased renal excretion
*Pts most frequently die of respiratory failure or CV collapse

==Precipitants==
#Overdose
#Renal failure
#Volume depletion
##Diuretic use, vomiting, diarrhea, diaphoresis, decreased oral intake
#Hyperthermia
#Infection
#CHF
#Surgery
#Cirrhosis

==Clinical Features==
#GI
##Usually first to develop
##N/V
##Diarrhea
##Generalized abd pain
#CNS
##Usually develops as GI symptoms are abating; more common in chronic toxicity
##Tremor
##Muscle weakness
##Ataxia
##Stupor
##Seizure
##Coma
#Cardiac
##Hypotension
##Conduction Abnormalities
##Ventricular dysrhythmias
##Prolonged QT, transient ST depression, TWI
#Endocrine
##Hyper/Hypothyroidism or hyperparathyroidism
##Hypothyroidism most common
# Renal
##Nephrogenic Diabetes Insipidus 
###Can be seen mildly at therapeutic levels
###Causes polyuria and polydipsia

==Diagnosis==
*Lithium level
**Therapeutic level = 0.6-1.2 meq/L
**''level may be falsely elevated if placed in a green top tube due to the heparin lithium interaction''
*Metabolic Panel
**↑ Na 2/2 nephrogenic diabetes insipidus
**Evaluate renal function
*TSH
*ECG
**QT prolongation
**T-wave flattening or inversion
*Acetaminophen and Salicylate Levels (possible coingestants)

==Treatment==
#GI decontamination
##Consider lavage for massive ingestions (>4gm) if can be performed w/in 1hr
##Activated charcoal is ineffective
#Fluid resuscitation
##Average pt has Na/volume deficit; giving fluid helps reestablish normal Li excretion
###Give 2L NS bolus; then give 200mL/hr
#Seizure
##Benzos are 1st line
##Phenobarbital is 2nd line
##Phenytoin is ineffective
#Dialysis
##Indications:
###Li level >4 (acute overdose)
###Li level >3.5 (chronic toxicity)
###Little change in Li level after 6hr IVF
###Sustained Li level >1.0 after 36hr
###Baseline renal failure
###Ingestion of sustained-release preparations
##Goal:
###Li level <1
####Must monitor for up to 8hr following dialysis to ensure levels stay <1

==Disposition==
*Consider discharge for pts asymptomatic after 4-6hr obs with 2 downtrending levels
*Admit all pts w/ Li level >1.5
*Admit all pts w/ ingestion of sustained-release preparation (regardless of Li level)

==See Also==
*[[Toxicology (Main)]]

==References==
<references/>
*Tintinalli
*Rosen's Chapter 160 - Lithium

[[Category:Tox]]