Learning Objectives
By the end of this section, you will be able to:
- Examine various categories of IV fluids
- Recognize the different ways to regulate IV flow rates
- Recall the guidelines for catheter, solution, and tubing changes
- Identify expected versus unexpected findings with IV therapy
The use of IV therapy is common in the delivery of health care. Fluid replacement is one of the most common indications for requiring IV therapy. As the nurse, you will be responsible for initiating and maintaining IV infusions. This section prepares you to understand how IV fluid therapy works within the body; ways to regulate IV flow rates; and how to assess, maintain, and prevent complications related to IV therapy.
Categories of Intravenous Fluids
There are several different ways to characterize IV fluids. An IV fluid may be categorized as colloid and crystalloid, depending on the size of the molecules and whether the molecules are soluble or insoluble. An IV fluid may be further categorized by its tonicity as an isotonic, hypotonic, or hypertonic solution.
Colloids
A colloid contains large, insoluble molecules that are evenly dispersed throughout the solution. These molecules may be composed of proteins, complex polysaccharides, albumin, starches, and dextran. Because the insoluble molecules are large, they do not cross the capillary wall easily and remain in the vascular space longer than crystalloids. Therefore, you need less fluid volume when infusing colloids to achieve the same effect as crystalloids. Colloids are used to expand intravascular volume by drawing fluid from the extravascular space using high osmotic pressure. Indications for colloidal fluids include hypovolemic shock, burns, sepsis, trauma, and surgery. One disadvantage for the use of colloids is the cost.
Crystalloids
A crystalloid contains water-soluble electrolytes, such as sodium and chloride. Crystalloids lack the proteins and other insoluble molecules found in colloids. Because crystalloids contain water-soluble components, they cross the capillary wall easily and quickly. Therefore, you need more fluid volume when infusing crystalloids to achieve the same effect as colloids. Crystalloids increase fluid volume in the interstitial and intravascular spaces. Crystalloid fluids are the first choice for fluid resuscitation in the presence of hypovolemia, hemorrhage, sepsis, and dehydration.
Tonicity
The ability of the solution to alter the volume of the cell by moving water in and out of the intracellular and intravascular spaces is referred to as tonicity. Solutions can be hypertonic, isotonic, or hypotonic (Figure 13.21).
Hypertonic
A hypertonic solution contains a higher concentration of solutes than plasma and creates osmotic movement to pull the water from the cellular space into the intravascular space, causing the cell to shrink. Hypertonic solutions are also known as volume expanders because they increase extracellular volume (Vera, 2024). Examples of hypertonic solutions include 3 percent sodium chloride (3 percent NaCl), 5 percent sodium chloride (5 percent NaCl), 10 percent dextrose in water (D10W), dextrose 20 percent in water (D20W), dextrose 50 percent in water (D50W). It is important to monitor the patient for signs of hypervolemia and hyperglycemia. If the hypertonic solution contains saline, also monitor sodium levels closely. Due to the seriousness of the potential side effects, hypertonic solutions are typically administered in acute care settings because they require close monitoring of the patient’s vital signs, electrolyte levels, and clinical status, as well as adjustments to the infusion rate as needed. Because hypertonic solutions are vesicants, they should be administered through a central line.
Isotonic
An isotonic solution contains a similar concentration of particles as plasma. Because there are equal concentrations in the intracellular and extracellular spaces once administered, osmotic movement does not occur, and the fluid stays within the intravascular space. Isotonic solutions increase extracellular fluid volume. They may be indicated when a patient requires fluid and electrolyte replacement, such as with blood loss, surgery, dehydration, and hypotension. Examples of isotonic solutions include 0.9 percent normal saline solution (0.9 percent NaCl), 5 percent dextrose in water (D5W), lactated Ringer solution in 5 percent dextrose (D5LR), and Ringer solution (Vera, 2024). When administering isotonic solutions, it is important to monitor the patient for fluid overload.
Hypotonic
A hypotonic solution contains a lower concentration of particles than plasma and creates osmotic movement that pulls the water from the intravascular space into the cellular space, causing the cell to swell. Hypotonic solutions are used to increase intracellular fluid volume. They may be indicated for patients experiencing diabetic ketoacidosis (DKA) or hyperosmolar hyperglycemia. Examples of hypotonic solutions include 0.45 percent sodium chloride (0.45 percent NaCl), 0.225 percent sodium chloride (0.255 percent NaCl), 0.33 percent sodium chloride (0.33 percent NaCl), and 2.5 percent dextrose in water (D2.5W). Too much hypotonic fluid can cause cerebral edema and can worsen hypovolemia and hypotension. Hypotonic solutions are contraindicated in patients at risk for increased cranial pressure or with extensive burns, liver failure, or trauma. Table 13.1 summarizes the characteristics of hypertonic, isotonic, and hypotonic IV solutions.
| Hypotonic | Isotonic | Hypertonic | |
|---|---|---|---|
| Concentration of particles compared to plasma | Lower concentration of particles than plasma | Same concentration of particles as plasma | Higher concentration of particles than plasma |
| Used when | Less solutes in intravascular space than in intracellular space | Same solutes in intravascular and intracellular spaces | More solutes in intravascular space than in intracellular space |
| Examples | 0.45 percent NaCl, 0.255 percent NaCl, 0.33 percent NaCl, and D2.5W | 0.9 percent NaCl, D5W, D5LR, and Ringer solution | 3 percent NaCl, 5 percent NaCl, D10W, D20W, and D50W |
| Osmosis | Shifts fluid into cells | No fluid shift | Shifts fluid out of cells |
| Indications | Cellular hydration, such as with diabetic ketoacidosis (DKA) or hyperosmolar hyperglycemia | Fluid and electrolyte replacement, such as with blood loss, surgery, dehydration, and hypotension | Hypovolemia, vascular expansion |
| Watch for | Cerebral edema, hypovolemia, and hypotension | Hypervolemia, edema, diluted laboratory values | Hypervolemia, difficulty breathing, elevated blood pressure, pulmonary edema, increased sodium, hyperglycemia, cellular dehydration, extravasations |
| Contraindications | Hypotension, increased intracranial pressure, extensive burns, stroke, liver failure, trauma | Volume overloaded patients | Cardiac and kidney failure (risk of pulmonary edema), dehydration |
Ways of Regulating Intravenous Flow Rates
Intravenous fluid regulation refers to controlling the amount and rate of fluid received intravenously. Regulation ensures that you administer the correct amount at the correct rate. Failure to regulate IV flow rate appropriately can cause complications from receiving too much fluid too quickly or not enough fluid fast enough. There are several different ways of regulating IV flow rates, including gravity infusion, pump infusion, IV push, continuous single infusions, and continuous multiple infusions.
Gravity Infusion
When infusing IV fluids by gravity, the healthcare provider regulates the infusion rate by using a clamp on the IV tubing, which can either speed up or slow down the flow of IV fluids. An IV flow rate for gravity is calculated in drops per minute (gtt/min). To calculate the gtt/min, multiply the infusion rate (mL/hr) by the IV drop factor (gtt/min) found on the IV tubing, then divide by the infusion time in minutes. For example, a fluid that is to be infused at a rate of 75 mL/hr via 15 gtt tubing would infuse at a rate of 19 gtt/min [(75 × 15)/60 = 18.75 gtt/min]. Drops can only be administered whole, so round up if greater than 0.5, and round down if less than 0.5.
To ensure the correct rate, observe the drip chamber, and count the number of drips for one full minute. Alternatively, divide the drops per minute by four to get the drops per fifteen seconds. For example, divide nineteen drops by four to determine that approximately five drops should fall every fifteen seconds. Assess the drops per minute regularly to make sure that the IV is infusing at the correct rate (e.g., check every one to two hours, if the patient accidentally bumps the IV tubing, or if a patient returns from another department).
Pump Infusion
With pump infusion, the infusion rate is regulated electronically, which delivers the fluids at the correct rate and volume. All IV pumps regulate the rate of fluids in milliliters per hour (mL/hr). Electronic pump infusion is recommended in all settings to reduce infusion-related medication errors (INS, 2024). Most IV pumps have embedded drug libraries in which the usual concentrations, rates, dosing, and dose limits are stored for each medication. The nurse carefully chooses the right medication, amount, and length of infusion required to ensure safe delivery of IV medications.
Intravenous Push
Medications via IV push are administered through the access port on the primary tubing that is closest to the patient. If the patient does not have continuous fluids running, flush the IV site before and after administering the IV push medication. Always follow the agency’s policy, because some agencies require running fluids to be connected when administering IV push medications to prevent an accidental bolus of medication. The rate at which IV push medications are administered varies depending on the type of medication. A typical guideline is to administer 1 mL over one minute. Some drugs are administered more slowly, however, such as pushing 40 mg IV furosemide IV over two minutes to prevent hearing loss. Still other drugs should be administered more rapidly, such as pushing emergency medications as quickly as possible during a code. It is the nurse’s responsibility to push the medication at the correct rate. If in doubt, you can find the IV push rate in medication guidebooks, in the electronic medication administration record (eMAR), or through the pharmacy.
Clinical Safety and Procedures (QSEN)
QSEN Competency: Administering Medications by Intravenous Bolus or Push through an Intravenous Solution and Administering Medications by Intravenous Bolus or Push through a Medication or Drug-Infusion Lock
See the competency checklists for Administering Medications by Intravenous Bolus or Push through an Intravenous Solution and Administering Medications by Intravenous Bolus or Push through a Medication or Drug-Infusion Lock. You can find the checklists on the Student resources tab of your book page on openstax.org.
Continuous Single Infusions
Continuous single infusions are constant infusions of a parenteral drug over several hours or days. You will sometimes hear a continuous infusion referred to as a continuous drip. Examples of continuous infusions typically administered on medical units include heparin, insulin, and pantoprazole. Examples of continuous infusions typically administered in critical care settings (due to the need for close monitoring) include propofol, diltiazem, vasopressin, and nitroglycerin.
Monitor lab values closely when a patient is receiving medications via continuous infusion to ensure proper titration of the medication dose. Continuous infusions always include use of an IV pump to make sure the medication is being administered at the correct rate. Often, the patients will require IV fluids and medications in addition to the continuous infusion.
If the continuous medication and the primary IV fluids are compatible, you may be able to administer them through the same IV. To do so, connect each IV bag to separate primary tubing. Program each primary tubing set into the IV pump using a separate channel (Figure 13.22). Each channel will regulate the rate and duration of one medication being infused. The primary tubing of the IV fluids is then connected to the patient’s IV site, and the tubing for the continuous infusion is connected to the access port located on the tubing of the IV fluids closest to the patient. If the medications and fluids are not compatible, the nurse may need to use more than one IV site simultaneously to infuse the medications.
Clinical Safety and Procedures (QSEN)
QSEN Competency: Administering a Piggyback Intermittent Intravenous Infusion of Medication
See the competency checklist for Administering a Piggyback Intermittent Intravenous Infusion of Medication. You can find the checklists on the Student resources tab of your book page on openstax.org.
Continuous Multiple Infusions
Critically ill patients sometimes require coadministration of multiple continuous infusions. While the process is the same as continuous single infusions, administering multiple continuous infusions adds an extra layer of complexity during setup. The nurse must carefully consider compatibility of all medications running through the same tubing and IV site. Often, the situation will require additional IVs or a central line with multiple lumens.
To ensure patient safety, be certain to label all IV bags, tubing, and IV pump channels correctly, and make sure that they are connected to the intended IV tubing. The risk of error increases as you add more infusions into a patient’s regimen. Not only should the nurse consider which medications can be administered through the same IV line, but they should also confirm that the correct medication is running through the correct channel at the correct rate. Failure to do so could result in serious medication errors and patient harm.
Guidelines for Catheter, Solution, and Tubing Changes
To minimize the risk of infections, follow guidelines for catheter, solution, and tubing changes. According to the Centers for Disease Control and Prevention (CDC), peripheral IV catheters should be routinely changed no more frequently than seventy-two to ninety-six hours (Webster et al., 2019). Of course, the site may need to be changed more frequently if complications arise, such as infiltration or phlebitis. Some institutions, however, may opt to avoid routine IV catheter changes and change the IV catheter only when the site assessment looks abnormal with redness, swelling, or irritation.
Intravenous solutions are typically good for twenty-four hours after they are opened. If the solution has expired or been open for longer than twenty-four hours, dispose of the solution according to the agency’s policy. If there is no date or time on the IV solution, assume the solution is expired and obtain a new bag of fluids. If the solution is still within date but appears cloudy or has precipitates, dispose of the fluids and obtain a new bag. Additionally, if the patient has an IV running but is prescribed a new IV mixture, the nurse must disconnect the old IV bag and administer the newly prescribed mixture. The old IV bag must be discarded according to facility guidelines.
Clinical Safety and Procedures (QSEN)
QSEN Competency: Changing an IV Solution
See the competency checklist for Changing an IV Solution. You can find the checklists on the Student resources tab of your book page on openstax.org.
Primary IV tubing should be changed every seventy-two to ninety-six hours, depending on the agency’s policy. If the tubing is secondary or intermittent fluids are administered, some agencies may require a tubing change every twenty-four hours due to the increased risk of contamination. Consider also the type of fluid being infused. For example, tubing used for total parenteral nutrition (TPN) must be changed every twenty-four hours, whereas tubing used for blood and blood products must be changed every four hours or four units, whichever comes first. Tubing for propofol must be changed every six to twelve hours, or when the vial is changed, to prevent bacterial growth. Intravenous tubing should also be changed if the IV tubing becomes disconnected or touches nonsterile surfaces.
Clinical Safety and Procedures (QSEN)
QSEN Competency: Changing IV Tubing
See the competency checklist for Changing IV Tubing. You can find the checklists on the Student resources tab of your book page on openstax.org.
Central Venous Catheter Maintenance Bundles
A CVC requires special care. A CVC maintenance bundle may reduce the risk of CLABSIs. Typically, CVC maintenance bundles include proper hand hygiene, routine dressing changes, aseptic technique for accessing and changing tubing, standardized tubing changes, and daily review of catheter necessity. Perform proper hand hygiene prior to accessing the catheter, administering medication, changing the dressing, or palpating the catheter insertion site. Wear sterile gloves when changing the dressing. Cleanse the site with greater than 0.5 percent chlorhexidine solution for thirty seconds and allow it to dry completely before applying a sterile, transparent dressing or sterile gauze. Perform routine dressing changes at least every seven days or when the dressing gets wet or soiled (INS, 2024). Gauze dressings should be replaced every forty-eight hours (INS, 2024). Scrub catheter access ports and needleless connectors with chlorhexidine (or other approved antiseptic solution) prior to accessing the access port. Change needleless connectors no more frequently than every seventy-two hours, or according to the agency’s policy. Change out IV tubing that is used continuously, including secondary sets, no more frequently than every ninety-six hours but at least every seven days. Exceptions to this replacement timeline include TPN, blood and blood products, chemotherapy, and propofol, which are changed more frequently according to the agency’s policy. The last portion of the bundle, assessing the need for the CVC, allows for daily review of the necessity of the catheter, so the catheter can be removed as soon as it is deemed medically safe to do so (INS, 2024).
Central Line–Associated Bloodstream Infection Guidelines
A central line–associated bloodstream infection (CLABSI) is a hospital-acquired infection caused by microorganisms being introduced into the bloodstream through the IV site, access ports, or contaminated IV tubing or IV solutions. CLABSIs are diagnosed by positive blood cultures and treated with antibiotics. As a result of bacteria entering the bloodstream, the patient may experience serious complications, such as bacteremia, bacteria in the blood, or sepsis, a dysregulated immune response to infection that triggers widespread inflammation throughout the body and potential organ failure. CLABSIs are adverse events that result in unnecessary healthcare costs and patient deaths each year.
It is important to note that CLABSIs are preventable. The number one way to prevent a CLABSI is to remove central lines as soon as is medically possible. If the patient does not have a central line, they cannot get a CLABSI. Another way to prevent the risk of infection is to adhere to all CVC maintenance bundles, including using strict aseptic technique for all line care and maintenance. Because CLABSIs are preventable, they are reported as an indicator of quality nursing care. The goal is to keep patients safe by having zero CLABSIs.
Link to Learning
The Joint Commission created a CLABSI Toolkit that contains evidence-based strategies and techniques for preventing CLABSIs.
Expected versus Unexpected Findings with Intravenous Therapy
Patients receiving IV therapy are at risk for developing complications. Routine assessment is critical for preventing or reducing potential IV-related complications. Included in this assessment are inspection and ensuring IV patency, meaning that the IV line is open and unobstructed. To accurately assess the IV, the nurse must have a clear understanding of the expected versus unexpected findings with IV therapy. IVs should be assessed at the beginning of the shift, end of the shift, when the IV pump alarms, and upon administration of IV medications. Patient complaints of pain, tenderness, or discomfort at the site warrant additional assessments of the IV. Assessment of the IV includes assessing not only the IV site itself but also the tubing, rate, and solution.
Life-Stage Context
Life Span Considerations when Assessing an IV
Children
Safety measures for a child with an IV infusion include assessing the IV site every hour for patency. Carefully assess and document frequently, per agency policy, infused volumes and signs of fluid overload. You can wrap the IV in gauze or use an arm board to deter the child from tampering with the IV site or tubing. Additionally, secure the tubing well and make sure that the dressing remains free from moisture, so the IV site is not compromised. Be aware that mobile children will require guidance to ensure that the tubing does not become obstructed if they sit or lie on it accidentally.
Older Adults
Frequently monitor older adults with an IV infusion for development of fluid volume overload. Signs of fluid volume overload include elevated blood pressure and respiratory rate, decreased oxygen saturation, peripheral edema, fine crackles in the posterior lower lobes of the lungs, or signs of worsening heart failure. Additionally, older adults have delicate venous walls that may not withstand rapid infusion rates. It is important to monitor the IV site patency carefully when infusing large amounts of fluids at faster rates, and appropriately modify the infusion rate.
Inspection
The nurses’ inspection of the IV is as thorough as if they are about to start a new IV. Everything must be checked and double-checked. First, review the chart to determine the type of IV solution and rate of infusion ordered. Make sure that the correct solution is infusing and is not expired. Note the date and time of the bag currently being infused. If it has been twenty-four hours since initiation, most likely the bag must be changed. Check the label to see when the previous nurse started the infusion. If there is no label, then obtain a new bag. Generally, IV solutions are changed before they pass twenty-four hours. When in doubt or the label is unclear or absent, get a new bag and follow agency policy.
Inspect and make sure that the solution is infusing at the correct rate according to the medical administration record. If the IV solution is being infused via an IV pump, ensure that the rate is programmed correctly, the IV roller clamps are open, and the IV pump is plugged into the outlet. If a secondary infusion is running, be sure that the roller clamp is open and the secondary IV solution is hung above the level of the primary IV solution. If the IV solution is running by gravity, calculate and count the drip rate for one minute to verify that the medication is infusing at the correct rate.
Inspect the IV tubing to certify that there are no kinks or bends. Kinks or bends may prevent the flow of the infusion. Confirm that the tubing is neatly arranged and not tangled up in equipment or dislodged between the siderails on the bed. Assess the expiration date on the IV tubing. If the tubing is expired or not dated, discard the tubing, and obtain new tubing. Follow the tubing down to the IV site to make sure that the tubing is securely attached to the IV access port.
Inspect the IV insertion site. The IV site should be free from pain, tenderness, redness, swelling, warmth, coolness, and leaking. If the site is painful, tender, red, swollen, warm, cool, or leaking, stop the infusion, remove the IV, document the assessment findings, and notify the provider. The transparent dressing should be clean, dry, intact, and secured to the skin. The IV site should be labeled with the date and time of the insertion, initials of the person who inserted the IV, the gauge of the IV, and the date the site is to be changed, according to the agency’s policy.
Patency
Assess the patency of the IV to certify that the IV is open and the IV solution can freely flow into the patient’s vein. If continuous fluids are running and the IV is not leaking or showing signs of phlebitis or swelling around the site, the IV is patent. If the IV fluid does not flow freely, the site is not patent, and the IV should be removed and restarted. Ensure that the dressing is properly protecting the site.
Clinical Safety and Procedures (QSEN)
QSEN Competency: Changing a Peripheral Venous Access Site Dressing
See the competency checklist for Changing a Peripheral Venous Access Site Dressing. You can find the checklists on the Student resources tab of your book page on openstax.org.
If continuous fluids are not running, flush the IV every twelve hours to preserve patency and reduce the risk of thrombosis or occlusion of the line. Flush peripheral IVs with 3 to 5 mL of normal saline; flush central lines with 10 mL of normal saline or heparin, unless otherwise indicated by the provider’s order or agency’s policy. If the site does not flush, the site is not patent, and you should remove and restart the IV. Document patency and IV flushing as part of the routine IV assessment.