Deficient fluid volume, or hypovolemia, results from a loss of body fluid or fluid shift, causing the fluid output to surpass fluid intake. In this process (acute or chronic), the body loses fluid volume and electrolytes. The source for this condition can be gastrointestinal, renal, or even metabolic.
This information helps guide interventions. For example, treatment for chronic anemia will be different than for fluid loss from inadequate oral intake. Causes for fluid volume can differ significantly and warrant specific treatment. If risk factors (vomiting, diarrhea, diabetes mellitus, fever, diuretic treatment) can be identified early, treatment can be initiated and possibly decrease complications.
Low blood volume in the intravascular space causes low blood pressure. Consequently, heart rate may be increased as this is a compensatory mechanism to maintain a sufficient cardiac output.
Orthostatic hypotension is a significant drop in blood pressure with position changes. To assess orthostatic hypotension, the nurse obtains blood pressure in the supine, sitting, and standing positions. Orthostasis is considered positive if there is a 20mmHg drop in systolic pressure or a 10mmHg in diastolic pressure.
Urine output of at least 30ml per hour indicates adequate perfusion of the kidneys. Less than that may indicate insufficient fluid volume.
Urine dark in color with an increased specific gravity may mark an increased urine concentration and volume deficit.
Most patients do not keep track of the daily amount of fluid they consume. Some patients, especially elderly patients, may simply forget about drinking enough water throughout the day. Others might not drink a lot of water because they are on fluid restriction. Therefore, tracking accurate intake and output is essential to guide appropriate treatment.
Loss of blood volume and dehydration can cause irritability, fatigue, restlessness, and confusion. Consider these changes, especially for the older population.
Thirst
Non-elastic skin turgor
Dry, cracked mucous membranes
Sunken eyes
Oliguria
Central venous pressure (CVP)
Pulmonary artery pressure (PAP)
Pulmonary capillary wedge pressure (PCWP)
These continuous hemodynamic parameters provide information about treatment response and can help guide therapy. In addition, this sensitive monitoring is beneficial for patients with cardiac and renal problems or patients with a septic profile.
Sudden weight loss may be indicating a loss of water weight, especially in the presence of other symptoms pointing to volume loss, such as decreasing urine output.
Distribute the amount of fluids throughout the entire day. Provide 2/3 of the fluids prescribed during the day and 1/3 at night. For example, offer 1000ml during the day shift and 500ml on the night shift for a total of 1500ml prescribed.
Patients are more likely to increase their fluid intake if they like the flavor and temperature of the beverage. Consider popsicles and fruit juices to supplement fluid intake.
Patients often may be too weak to feed themselves and become frustrated because they need help. This could be demotivating for the patient and worsen the situation of decreased fluid intake.
Dehydration can cause the mouth to feel dry and tacky. Frequent oral hygiene makes it more comfortable and enjoyable to eat and drink.
Fluids within the patient’s visual field serve as a constant reminder to take in fluids. Sometimes water pitchers are too heavy for patients to lift. In that case, provide a glass of water, which will be easier to lift. Also, provide a straw if needed. Easy access to fluids promotes increased fluid intake.
Administer antidiarrheals, antipyretics, and antiemetics to reduce fluid loss, if the patient experiences ongoing diarrhea and vomiting.
Intravenous fluid replacement therapy is sometimes necessary to maintain an appropriate fluid balance if oral intake is not possible or insufficient. Central lines with central venous pressure (CVP)monitoring and pulmonary artery catheters provide information about the patient’s fluid status. Arterial lines allow for continuous blood pressure monitoring.
Intravenous fluids ensure more consistent hydration than oral fluid intake. Physicians perform fluid challenges to see if the patient has a preload reserve that can be used to improve cardiac function and fluid status.
Trending such tests allows the healthcare team to monitor whether treatment is effective or if other strategies need to be considered.
Electrolyte levels can change drastically with fluid volume loss, whether it be blood loss or losing volume due to vomiting and diarrhea. Decreased electrolyte levels can cause dysrhythmias, muscle spasms, and fatigue.
Older patients experience physiological changes that can affect fluid balance.
Thirst sensation is decreased in older patients. Therefore, repeated offers to drink fluids are essential for fluid replacement therapy in older patients.
Skin loses elasticity with age; therefore, older adults commonly have decreased baseline skin turgor.
Patients with impaired mentation may not be able to maintain a necessary fluid balance. Therefore, assistance with fluid intake and frequent reminders are essential.
Providing a rationale promotes compliance and helps prevent the issue.
The patient needs to know cup and ounces measurements to be able to track fluid intake.
Potter, P., & Perry, A. (2013). Fundamentals of nursing (8th ed.). Elsevier.
Ackley, B., & Ladwig, G. (2014). Nursing diagnosis handbook (10th ed). Maryland Heights: Mosby Elsevier.
