- determine volume status of the patient;
- SIADH (Normovolemic)
- Volume Excess Hyponatremia
- Volume Depleted Hyponatremia;
- may be seen endurance athletes, military, and marathoners after prolonged exertion;
- due to excess free water intake that fails to replete massive sodium losses that result from sweating;
- exercise-induced hyponatremia is generally asymptomatic;
- usually symptoms arise when sodium level falls below 125 mEq/L;
- fluid balance should be maintained with sports beverages (which have 4-8% carbohydrates)
- oral rehydration with salty solutions is safe and effective in patients with mild symptoms;
- Hyponatremia among Runners in the Boston Marathon
- Exercise-induced hyponatremia: causes, risks, prevention, and management.
- Hyponatremia in distance runners: fluid and sodium balance during exercise.
- if the patient has Normal ECF volume, SIADH, psuedohyponatremia, or endocrine d/o (hypothyroidism) should be considered;
- many hyponatremic states are asymptomatic until the serum sodium level falls well below 120 mEq per liter;
- one exception is the patient w/ increased CSF pressure, (as following closed head injury), in which mild hyponatremia may be extremely deleterious, even fatal;
- this is due to the progressive increase in intracellular water (further increaseing intracranial pressure) as the extracellular fluid osmolarity falls);
- brainstem herniation: requires rapid correction;
- central pontine myelinolysis: occurs from too rapid correction;
- ref: Myelinolysis after correction of hyponatremia.
Hyponatremia and syndrome of inappropriate antidiuretic hormone secretion in adult spinal surgery.
Prevalence, Timing, Causes, and Outcomes of Hyponatremia in Hospitalized Orthopaedic Surgery Patients
Post-operative hyponatraemia in orthopaedic injury.
Hyponatremia at admission is associated with in-hospital death in patients with hip fracture
Original Text by Clifford R. Wheeless, III, MD.
Last updated by Data Trace Staff on Thursday, January 7, 2016 9:12 am