Les troubles de l’équilibre hydrosodé chez les patients hospitalisés

Abstract

Purpose To review and discuss the epidemiology, contributing factors, and approach to clinical management of disorders of sodium and water balance in hospitalized patients. Source An electronic search of the MEDLINE, Embase, and Cochrane Central Register of Controlled Trials databases and a search of the bibliographies of all relevant studies and review articles for recent reports on hyponatremia and hypernatremia with a focus on critically ill patients. Principal findings Disorders of sodium and water balance are exceedingly common in hospitalized patients, particularly those with critical illness and are often iatrogenic. These disorders are broadly categorized as hypo-osmolar or hyper-osmolar, depending on the balance (i.e., excess or deficit) of total body water relative to total body sodium content and are classically recognized as either hyponatremia or hypernatremia. These disorders may represent a surrogate for increased neurohormonal activation, organ dysfunction, worsening severity of illness, or progression of underlying chronic disease. Hyponatremic disorders may be caused by appropriately elevated (volume depletion) or inappropriately elevated (SIADH) arginine vasopressin levels, appropriately suppressed arginine vasopressin levels (kidney dysfunction), or alterations in plasma osmolality (drugs or body cavity irrigation with hypotonic solutions). Hypernatremia is most commonly due to unreplaced hypotonic water depletion (impaired mental status and/or access to free water), but it may also be caused by transient water shift into cells (from convulsive seizures) and iatrogenic sodium loading (from salt intake or administration of hypertonic solutions). Conclusion In hospitalized patients, hyponatremia and hypernatremia are often iatrogenic and may contribute to serious morbidity and increased risk of death. These disorders require timely recognition and can often be reversed with appropriate intervention and treatment of underlying predisposing factors.

Correction of Hyper- and Hyponatraemia during Continuous Renal Replacement Therapy

“…Hypernatraemia is defined as serum [Na + ] >145 mmol/l and develops in 1% of hospitalized patients and up to 9% of patients admitted to ICUs [1]. It is independently associated with increased mortality [6].…”

“…Risk factors include older age, brain injury, altered mental status, diabetes mellitus, surgery and certain drugs [1,3]. The clinical manifestations, typically nausea, anorexia, restlessness and lethargy, are related to cerebral dysfunction secondary to water shift out of brain cells [1].…”

“…The clinical manifestations, typically nausea, anorexia, restlessness and lethargy, are related to cerebral dysfunction secondary to water shift out of brain cells [1]. Decreased consciousness, irritability, hyperreflexia and seizures may develop as hypernatraemia worsens.…”

“…Excess sodium stores, when involved, can only be excreted if renal function is adequate [3]. The rate of correction should not exceed 10-12 mmol/day (0.5 mmol/l/h) [1,7]. A rapid decrease in serum [Na + ], especially in chronic situations when compensation has occurred, can lead to significant water shifts into brain cells and cerebral oedema.…”

“…Sodium disorders are frequent in hospitalized patients, especially in the intensive care unit (ICU) [1] and often co-exist with acute kidney injury (AKI). Controlled normalization of serum [Na + ] is crucial as rapid correction can lead to cerebral oedema and osmotic demyelination syndrome (ODS) [2,3,4].…”