overhydration


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Overhydration

 

Definition

Overhydration, also called water excess or water intoxication, is a condition in which the body contains too much water.

Description

Overhydration occurs when the body takes in more water than it excretes and its normal sodium level is diluted. This can result in digestive problems, behavioral changes, brain damage, seizures, or coma. An adult whose heart, kidneys, and pituitary gland are functioning properly would have to drink more than two gallons of water a day to develop water intoxication. This condition is most common in patients whose kidney function is impaired and may occur when doctors, nurses, or other healthcare professionals administer greater amounts of water-producing fluids and medications than the patient's body can excrete. Overhydration is the most common electrolyte imbalance in hospitals, occurring in about 2% of all patients.
Infants seem to be at greater risk for developing overhydration. The Centers for Disease Control and Prevention has declared that babies are especially susceptible to oral overhydration during the first month of life, when the kidneys' filtering mechanism is too immature to excrete fluid as rapidly as older infants do. Breast milk or formula provide all the fluids a healthy baby needs. Water should be given slowly, sparingly, and only during extremely hot weather. Overhydration, which has been cited as a hazard of infant swimming lessons, occurs whenever a baby drinks too much water, excretes too little fluid, or consumes and retains too much water.

Causes and symptoms

Drinking too much water rarely causes overhydration when the body's systems are working normally. People with heart, kidney, or liver disease are more likely to develop overhydration because their kidneys are unable to excrete water normally. It may be necessary for people with these disorders to restrict the amount of water they drink and/or adjust the amount of salt in their diets.
Since the brain is the organ most susceptible to overhydration, a change in behavior is usually the first symptom of water intoxication. The patient may become confused, drowsy, or inattentive. Shouting and delirium are common. Other symptoms of overhydration may include blurred vision, muscle cramps and twitching, paralysis on one side of the body, poor coordination, nausea and vomiting, rapid breathing, sudden weight gain, and weakness. The patient's complexion is normal or flushed. Blood pressure is sometimes higher than normal, but elevations may not be noticed even when the degree of water intoxication is serious.
Overhydration can cause acidosis (a condition in which blood and body tissues have an abnormally high acid content), anemia, cyanosis (a condition that occurs when oxygen levels in the blood drop sharply), hemorrhage, and shock. The brain is the organ most vulnerable to the effects of overhydration. If excess fluid levels accumulate gradually, the brain may be able to adapt to them and the patient will have only a few symptoms. If the condition develops rapidly, confusion, seizures, and coma are likely to occur.

Risk factors

Chronic illness, malnutrition, a tendency to retain water, and kidney diseases and disorders increase the likelihood of becoming overhydrated. Infants and the elderly seem to be at increased risk for overhydration, as are people with certain mental disorders or alcoholism.

Diagnosis

Before treatment can begin, a doctor must determine whether a patient's symptoms are due to overhydration, in which excess water is found within and outside cells, or excess blood volume, in which high sodium levels prevent the body from storing excess water inside the cells. Overhydration is characterized by excess water both within and around the body's cells, while excess blood volume occurs when the body has too much sodium and can not move water to reservoirs within the cells. In cases of overhydration, symptoms of fluid accumulation do not usually occur. On the other hand, in cases of excess blood volume, fluid tends to accumulate around cells in the lower legs, abdomen, and chest. Overhydration can occur alone or in conjunction with excess blood volume, and differentiating between these two conditions may be difficult.

Treatment

Mild overhydration can generally be corrected by following a doctor's instructions to limit fluid intake. In more serious cases, diuretics may be prescribed to increase urination, although these drugs tend to be most effective in the treatment of excess blood volume. Identifying and treating any underlying condition (such as impaired heart or kidney function) is a priority, and fluid restrictions are a critical component of every treatment plan.
In patients with severe neurologic symptoms, fluid imbalances must be corrected without delay. A powerful diuretic and fluids to restore normal sodium concentrations are administered rapidly at first. When the patient has absorbed 50% of the therapeutic substances, blood levels are measured. Therapy is continued at a more moderate pace in order to prevent brain damage as a result of sudden changes in blood chemistry.

Prognosis

Mild water intoxication is usually corrected by drinking less than a quart of water a day for several days. Untreated water intoxication can be fatal, but this outcome is quite rare.

Resources

Books

McPhee, Stephen, et al., editors. Current Medical Diagnosisand Treatment, 1998. 37th ed. Stamford: Appleton & Lange, 1997.

hy·per·hy·dra·tion

(hī'pĕr-hī-drā'shŭn),
Excess water content of the body; may result from the intravenous administration of unduly large amounts of glucose solution.
Synonym(s): overhydration
References in periodicals archive ?
When high school football player Walker Wilbanks died in Mississippi in August 2014 from overhydration, the doctor said that the cause of death was an "unpredictable freak occurrence".
However, the fluid status in a cohort of pediatric hemodialysis patients was evaluated by measuring the inferior vena cava (IVC) diameter and BIS, showing that overhydration detected by BIS and IVC diameters was not found to be correlated.
In summary, this article provides the basics of fluid replacement and recommendations that form the foundation of a hydration strategy to prevent heat illness and avoid overhydration injury.
Avoiding perioperative overhydration is important to minimize the risk of perioperative lung complications, but perioperative oxygen restriction in patients a few months after administration of bleomycin is not necessary [94, 95].
Factors leading to overhydration like water intake for urinary tract infections and ingestion of excess water during exercise can lead to precipitation of SIADH [21].
Broers et al., "Extracellular overhydration linked with endothelial dysfunction in the context of inflammation in haemodialysis dependent chronic kidney disease," PLoS ONE, vol.
and overhydration. We hereby aimed to study the effects of the SGLT2 inhibitor empagliflozin in healthy volunteers in artificially induced SIADH with focus on urinary volume excretion, glucosuria, and change of serum sodium level.
A randomized multicenter trial found that a "liberal fluid" regime may result in overhydration, leading to deleterious effects on cardiac and pulmonary function, recovery of gastrointestinal motility, tissue oxygenation, wound healing, and coagulation [12].
The most significant postoperative complication encountered was pulmonary congestion, which may have been associated with overhydration or minor aspiration in Case 3, but this resolved with appropriate medical treatment.
When urine and feces have prolonged contact, not only does skin overhydration occur, but the normally acidic skin pH becomes alkaline (Beeckman, 2017; Beeckman et al., 2015; Jeter & Lutz, 1996).
[9] Of these factors, overhydration (>1 500 mL/h) is considered the most prominent cause.