IV drugs

IV Fluids Review

💦 ⁠ IV fluids – What the tonic?

✏️The human body is composed of 60% water 💦 ⁠
-Two-thirds of it is available INTRAcellularly (space INside cells)⁠
-One-third of it is stored EXTRAcellularly (EXTERNAL space in blood vessels and around cells)⁠

⭐ There are different types of fluids with varying chemical compositions of salt and electrolytes that are designed to bring fluid into cells or keep fluid within the bloodstream.⁠

🔑 Key Tips:⁠
-Water flows where sodium (or particles) goes!⁠
-Solutions want to have the same ratio or balance of solvents (water) to solute (particles such as salt)⁠
-Water will flow from an area of low particles to an area of high particles⁠
-Semi-permeable membranes allow water to pass through but not particles⁠

⭐ First, think of the starting point as the space within blood vessels (or intravascular space) since IV fluids are infused directly into the bloodstream 🩸⁠

⭐ ISOtonic fluids: “ISOlated in the vasculature”⁠
-Equal amounts of water and particles so there is no movement between the compartments⁠
-Water from IV fluids stay ISOlated in the vasculature – used in situations where there is fluid loss and replacement is needed (ex: hemorrhage, diarrhea, vomiting)⁠
-Examples include: 0.9% sodium chloride (normal saline), dextrose 5% in water (D5W), lactated ringer (LR)⁠

⭐ HypOtonic fluids: “Out of the vasculature”⁠
-Low amounts of particles compared to water⁠
-Water flows OUT of the vascular into the cells⁠
-Used in situations where we have intracellular dehydration (ex: DKA, HHS)⁠
-Examples include: 0.45% sodium chloride (1/2 normal saline), 2.5% dextrose in water ⁠

⭐ HypErtonic fluids: “Enter the vasculature”⁠
-High amounts of particles compared to water ⁠
-Water ENTERS the highly concentrated vasculature from cells⁠
-Used in situations where there are swollen cells (ex: cerebral edema) or hyponatremia⁠
-Examples include: 3% sodium chloride (hypertonic saline), dextrose 10% in water (D10W) ⁠

IV chemotherapy agents with high emetic risks⁠

🌟 Chemotherapy agents are notorious for causing many side effects such as nausea and vomiting and are classified according to their emetic risk. 🤢🤮⁠

🌟 High-risk agents cause emesis in more than 90% of patients and require pre-treatment with medications such as 5HT3 antagonists (ex: ondansetron), neurokinin-1 receptor antagonists (ex: aprepitant), and dexamethasone. ⁠

🧠 A fun way to learn which IV chemotherapy agents have high emetic risk – think of this story: ⁠

‘The car had motion sickness and threw up, making splat sounds”⁠

🤔 Can you imagine it in your head? This story will help you remember the medications DACARbazine, Mechlorethamine, Streptozotocin, and ciSPLATin. ⁠

🌟 Other IV chemotherapy agents that have high emetic risk at higher doses or in combination with other medications include:⁠

-Carboplatin AUC>4⁠
-Carmustine >250 mg/m2⁠
-Cyclophosphamide >1500 mg/m3⁠
-Doxorubicin >60 mg/m2⁠
-Epirubicin >90 mg/m2⁠
-Ifosfamide >2 g/m2/dose⁠
-AC (any combo that contains an anthracycline + cyclophosphamide)