All about IV Therapy

IV therapy, also referred to as intravenous therapy, is the process of administering nutrients and water directly into the bloodstream so that the body can use them right away.

IV therapy delivers nutrients to the body at the fastest rate possible because it goes straight into the organs, bypassing the digestive system, resulting in a 90–100% absorption rate (compared to only 20–50% possible oral).

According to a PwC survey, one-third of UK workers report feeling stressed, depressed, or anxious. Given this, it is not surprising that the demand for IV vitamin clinics—which help to strengthen the immune system and increase energy—is rising.

IV Therapy has been around for centuries, despite the media portraying it as the newest health fad that is popular among athletes, stressed-out urban professionals, and Hollywood celebrities.

An Overview of IV Therapy’s Past

Though it wasn’t always the case, IV therapy is now used in wellness treatments like vitamin IV therapy in addition to life-saving therapeutic treatments. Bloodletting was a common practice in the past when blood was thought to be a medicinal substance in and of itself. This led to the development of blood therapy. Unfortunately, IV therapy was delayed for centuries due to medical ignorance about blood, blood types, and infectious agents like pyrogens, as well as a lack of materials like plastics.

Why are IV fluids used?

An intravenous tube can be used to inject liquids into veins to treat electrolyte imbalance and dehydration.

Before we get into the different types of IV fluids, let’s go over a few basic definitions to help you better understand what the fluid is doing to your cells.

Osmosis Solvent molecules move from a diluted solution to a concentrated solution through a semipermeable membrane during the osmosis process. This controls the solute concentration on both membrane sides.

Depending on the situation, they either produce a more diluted or concentrated solution by moving molecules into or out of a membrane.

Water likes to balance itself out, which means it will rush to areas where there isn’t any water. This is the most frequent cause of osmosis. As a result, a cell with low water content would rapidly absorb water molecules, which the cell membrane would control. If there were more water molecules inside the cell than outside, the water molecules would rush out.

Osmotic Force

Osmosis, or the pressure that prevents water from passing through a membrane, is controlled by osmotic pressure. By doing this, a cell is prevented from absorbing more water than it can manage, which could lead to the cell bursting. In short, it’s the pressure required to stop osmosis from occurring.

Many IV fluid types

The fluids can be used differently depending on whether these solutions are crystalloid or colloid, isotonic, hypotonic, or hypertonic. The prevalence of regular saline in hospitals and other healthcare settings has made crystalloid solutions the most popular for the time being. The patient’s needs determine the best fluid to use.


Semipermeable membranes are easily crossed by small molecules, such as those found in crystalloid solutions. Consider the membrane of your cell as a sieve. Since the particles in crystalloid solutions are small enough, they can fit through holes in cell membranes.

As a result, once your cells enter, they can easily access crystalloid solutions. Therefore, when medical professionals wish to increase fluid volume and intravascular space in the case of hypovolemia (loss of plasma) brought on by burns, trauma, or postoperative recovery, they frequently use crystalloids.

The following are different kinds of IV’s

  1. Regular Salinity

Other names for normal saline include 0.9NaCL, NS, and 9% normal saline.

Normal saline is generally isotonic and easily passes through cell membranes as a sterile, nonpyrogenic fluid.

The most popular use of this fluid is in extracellular spaces for fluid resuscitation because it works so well to treat a wide range of illnesses, such as shock, vomiting, diarrhea, and bleeding.

The circulating plasma volume is increased by this process (assuming the patient has enough red blood cells).

  • Blood exchange
  • replenishment of fluids in individuals with diabetic ketoacidosis
  • Alkalosis metabolism
  • Excessive Calcium
  • Low blood sugar

Moreover, the only fluid used during blood administration is regular saline. Patients with cardiac or renal complications should use it with caution because of the high sodium content, which can lead to excessive fluid retention and further strain the already fragile heart and kidneys.

  1. Saline Half Normal

Half normal saline, also known as 0.45NaCl or 45% normal saline, is a commonly used solution.

Half normal saline is a hypotonic, crystalloid solution of sodium chloride in sterile water that has half the chloride concentration of regular saline.

It can be applied to conditions like the following and is intended to treat patients with cellular dehydration:

  • Increasing your total volume of fluids
  • replacement of water
  • Low sodium chloride levels
  • DKA due to gastric fluid loss following normal saline but prior to dextrose infusions

It especially helps diabetic patients who are unable to handle glucose solutions. The solution should never be used in patients with burns, liver disease, or trauma since it dangerously depletes intravascular fluids. As with regular saline, the solution may pose a risk to an individual with cardiovascular disease or elevated intracranial pressure. Half normal saline still serves the same purpose as normal saline in terms of sustaining daily fluid levels, despite having half the sodium chloride content.

  1. Nursing Ringers

Lactated Ringer’s is another extremely popular IV fluid used in fluid resuscitation. You most likely received an injection of lactated ringers if you were injured and had surgery. It’s frequently used in place of regular saline.

Sydney Ringer, a physician, created a solution comprising sodium, chloride, calcium, and potassium in the late 1800s, and this is how the lactates got their name. The “lactated” portion of Lactated Ringers is attributed to Alexis Hartmann, who found that the solution was better suited for pediatric patients when lactate was added.

Although it is most frequently found in milk, our muscles can also produce it during physical activity. Since it contains electrolytes and a buffer (lactate), a saline solution containing these elements isotonic.

It is the closest thing to serum and plasma concentration found naturally in the body because it doesn’t contain magnesium like serum does.

  • Extreme or moderate dehydration
  • Burn victims are
  • Hypovolemia brought on by shifts in third-space fluid
  • Acute blood loss and fluid loss in the lower gastrointestinal tract
  • pH buffers and fluid replacement

Lactated Ringer’s cannot be used in patients with renal failure or complications because it can cause hyperkalemia due to its potassium content. Additionally, since liver disease patients are unable to properly metabolize lactate, it should not be administered to them. It also shouldn’t be given to patients whose pH is higher than 75.

  1. Dextrose

And lastly, there are numerous forms of dextrose.

One kind of simple sugar derived from corn is dextrose. It shares the same chemical makeup as glucose, which you should know as your trusty old sugar. Although it’s frequently added to baked goods and used in processed foods as a sweetener, it has a number of medical applications.

It’s beneficial in particular because, being a simple sugar, your body can use it for energy quickly. Dextrose solutions are available in three primary versions:

  • Dextrose in a liquid
  • Salted Dextrose
  • Dextrose in Ringer’s Lactated

Whatever kind of dextrose solution you use, the fundamental idea remains the same. Draped in the IV fluid, dextrose functions as a sugar that cells can easily absorb and utilize for energy.

  1. Water with Dextrose

Dextrose dissolved in water is one of the more popular forms of the sugar.

The solution of dextrose in water is crystalloid. It is physiologically hypotonic, but it is isotonic in the bag. That is another way of saying that it enters your body as an isotonic solution (while the sugar is still present), but that it changes to a hypotonic solution after your cells absorb the sugar.

Dextrose in water is not used in fluid resuscitation, in contrast to the other fluids we’ve listed so far, because it can result in hyperglycemia. Rather, it is employed for:

  • Make up a fluid volume shortfall.
  • Hydration
  • Hypernatremia: a low level of total body water in relation to electrolyte content results in an electrolyte imbalance.

For a variety of reasons, diabetic patients are frequently treated with dextrose dissolved in water instead of oral nutrition. The solution shouldn’t be used as a long-term food replacement because, despite having roughly 170 calories per liter, it is not sufficient to replace an average daily’s worth of calories.

Fascinatingly, it can also be used as a diluent—a lot of fluid to dilute a small dose of medicine—when preparing injectable medications for an IV bag. This is probably due to how easily dextrose is absorbed. Like the other fluids on this list, it should always be avoided in patients who have elevated intracranial pressure, heart issues, or renal failure because it can lead to fluid overload.

  1. Saline Dextrose

    IV Therapy
    IV Therapy

This solution is nonpyrogenic and sterile. It is, as the name suggests, a 5% dextrose solution in regular saline. Similar to regular saline, it starts out isotonic but turns hypertonic as the dextrose is absorbed (do you recall from before that working with hypertonic fluids can be particularly dangerous?).

Dextrose in saline is such a specialized fluid that it’s used in very specific situations, such as:

  • treating circulatory insufficiency temporarily, but only in the event that alternative plasma expanders are not available
  • low-sodium dehydration
  • Addisonian crisis: a potentially fatal illness brought on by an acute adrenal hormone deficiency
  • When the brain produces too much antidiuretic hormone, it is known as the syndrome of inappropriate antidiuretic hormone or SIADH.

Dextrose in saline, like many other fluids on this list, can induce heart failure or pulmonary edema, so it should not be used in patients with renal or cardiac problems.

  1. Lactated Ringers and Dextrose

It is a sterile, nonpyrogenic solution with 5% dextrose in Lactated Ringer’s that is used to replenish electrolytes and fluids. It is isotonic until the dextrose is absorbed, just like other dextrose solutions. The breakdown of the dextrose in this solution results in hypotonic fluid.

Although it can be used as an alkalinizing agent, it adds 180 calories per liter, much like Lactated Ringer’s. Numerous contraindications apply to it as well, since it is Lactated Ringer’s with dextrose. It is not recommended for use in patients with liver failure (again, because they cannot metabolize the lactate) or renal problems (due to concerns about hyperkalemia).

Because it contains dextrose, patients who have problems with glucose (diabetics, for example) should use it with caution. Additionally, even when using separate infusion lines, it shouldn’t be administered to babies younger than 28 days.

CollisionsColloidal solutions cannot pass through semipermeable membranes like crystalloid solutions can because of their larger molecules.

This means that, in terms of medicine, colloid solutions stay intravascular while crystalloid solutions do not. This implies that instead of entering your cells, they remain in your circulation. They are therefore utilized as plasma expanders in cases of severe hypovolemic shock as a method of fluid resuscitation.

The Differences Between Isotonic, Hypotonic, and Hypertonic

You can have isotonic, hypotonic, or hypertonic colloid and crystalloid solutions.

Your cells will not swell or contract in the presence of isotonic solutions because the solute concentrations in isotonic solutions differ from your cells’ concentrations.

Your cells have higher soluble concentrations than those found in hypotonic solutions. Consequently, the cell will swell as a result of water rushing in to balance the solute concentration.

Your body shrinks its cells to balance a hypertonic solution because it contains more solutes than your cells do.

A specialist will select between hypotonic, hypertonic, and isotonic solutions according to the desired mode of osmosis. For example, isotonic solutions are perfect for treating vomiting, diarrhea, shock, and metabolic acidosis because they maintain osmotic pressure both inside and outside the cell.

Patients who receive hypotonic solutions should be closely watched for hypovolemia and hypertension, though, as these treatments can cause cell swelling. Patients with high intracranial pressure should not receive these solutions as they may exacerbate cerebral edema or brain swelling.

Since a hypertonic solution removes fluid from the cells, patients must be continuously watched. While intravascular solutions carry some risks of their own, hypertonic solutions pose a particular risk due to their potential to induce pulmonary edema and intravascular fluid overload. Hypertonic solutions should therefore not be used for prolonged periods of time.

Why do people use intravenous fluids?

All of our body’s cells depend on water. Actually, water makes up roughly 60% of our bodies. Dehydration is the state in which your body lacks sufficient water. When a person becomes critically dehydrated, they require intravenous fluids.

Severe dehydration could happen if you:

  • ill (with diarrhea and vomiting).
  • Engage in excessive physical activity or prolonged exposure to heat without adequate hydration.
  • possess burns or a serious injury.
  • Get surgery, particularly if you won’t be able to eat or drink or if you’ll be unconscious for a long period.


What usually occurs during an IV therapy procedure is listed below:

A medical practitioner will select a vein before beginning the procedure in order to insert the cannula. This could be in the top of the foot, the back of the hand, the wrist, or the forearm. An ultrasonic scan may be used to guide the needle if a vein is hard to find.

The medical practitioner will use a wipe to sanitize the area after locating a vein and then insert a fine needle that is connected to a cannula. To keep the cannula in place, they might use adhesive tape.

Healthcare providers will attach the cannula to the IV using tubing after it is in place.

A medical practitioner will frequently check the cannula during the infusion to make sure the IV is flowing correctly and there is no pain or swelling in the affected area.

The medical practitioner will disconnect the cannula from the tubing and remove it from the vein after the IV therapy infusion is finished.

After that, they will apply pressure to the insertion wound in an effort to stop any bleeding. They might apply adhesive tape and a cotton bud to the area.

Healthcare providers will leave the cannula in place for procedures that call for a standard IV.

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