ATI chapter 57 Fluid and Electrolyte
Imbalances
- ANS
◯ Fluid can move between compartments (through selectively permeable membranes) by a
variety of methods - ANS(diffusion, active transport, ltration, osmosis) in order to maintain
homeostasis.
◯ Fluid imbalances that the nurse should be familiar with are: - ANS■ Fluid volume deficits
■ Fluid volume excess
electrolytes - ANSElectrolytes are minerals (sometimes called salts) that are present in all body
fuids.
They regulate fuid balance and hormone production, strengthen skeletal structures, and act as
catalysts in nerve response, muscle contraction, and the metabolism of nutrients.
When dissolved in water or another solvent, electrolytes separate into ions and then conduct
either a - ANSpositive ions: (cations - magnesium, potassium, sodium, calcium) or
negative ions: (anions - phosphate, sulfate, chloride, bicarbonate) electrical current.
Fluid volume de cits (FVDs) include - ANS◯Isotonic FVD is the loss of water and electrolytes
from the ECF.
■ Isotonic FVD is often referred to as hypovolemia because intravascular uid is also lost.
◯ Dehydration is the loss of water from the body without the loss of electrolytes.
■ This hemoconcentration results in increases in Hct, serum electrolytes, and urine speci c
gravity.
Older adults have an increased risk for dehydration due to multiple physiological factors
including a decrease in total body mass, which includes total body water content.
Causes of isotonic FVD (hypovolemia) - ANS■ Abnormal gastrointestinal (GI) losses - vomiting,
nasogastric suctioning, diarrhea
■ Abnormal skin losses - diaphoresis
■ Abnormal renal losses - diuretic therapy, diabetes insipidus, kidney disease, adrenal insuf
ciency, osmotic diuresis
■ Third spacing - peritonitis, intestinal obstruction, ascites, burns
■ Hemorrhage
■ Altered intake - impaired swallowing, confusion, nothing by mouth (NPO)
, Causes of dehydration - ANS■ Hyperventilation
■ Prolonged fever
■ Diabetic ketoacidosis
■ Enteral feeding without suf cient water intake
● Subjective and Objective Data for FVD - ANS◯ Vital signs - hypothermia, tachycardia,
thready pulse, hypotension, orthostatic hypotension,
decreased central venous pressure, tachypnea (increased respirations), hypoxia
◯ Neuromusculoskeletal - dizziness, syncope, confusion, weakness, fatigue
◯ GI - thirst, dry mucous membranes, dry furrowed tongue, nausea/vomiting, anorexia, acute
weight loss
◯ Renal - oliguria (decreased production of urine)
◯ Other clinical ndings - diminished capillary re ll, cool clammy skin, diaphoresis, sunken
eyeballs, attened neck veins, absence of tears, decreased skin turgor
- ANS◯ Hct - Increased in both hypovolemia and dehydration unless the fluid volume deficit is
due to hemorrhage.
◯ Serum osmolarity
■ Dehydration - increased hemoconcentration osmolarity (greater than 300 mOsm/kg) -
increased protein, BUN, electrolytes, glucose
◯ Urine specific gravity and osmolarity
■ Dehydration - increased concentration (urine speci c gravity greater than 1.030)
◯ Serum sodium
■ Dehydration - increased hemoconcentration
Compensatory mechanisms for FVD include sympathetic nervous system responses of
increased thirst - ANSantidiuretic hormone (ADH) release, and aldosterone release.
nursing care for FVD - ANS◯ Assess respiratory rate, symmetry, and effort.
◯ Monitor for shortness of breath and dyspnea.
◯ Check urinalysis, oxygen saturation (SaO2), CBC, and electrolytes.
◯ Administer supplemental oxygen as prescribed.
◯ Measure the client's weight daily at same time of day using the same scale.
◯ Observe for nausea and vomiting.
◯ Assess and monitor the client's vital signs (check for hypotension and orthostatic
hypotension).
◯ Check neurological status to determine level of consciousness.
◯ Assess heart rhythm (may be irregular or tachycardic).
◯ Initiate and maintain IV access.
◯ Place the client in shock position (on the back with the legs elevated).
◯ Fluid replacement: Administer IV uids as prescribed (isotonic solutions such as lactated
Ringer's or 0.9% sodium chloride; blood transfusions).