A bolus injection, also called an intravenous (IV) push, delivers a dose of medication all at once to allow rapid availability in the bloodstream with total absorption. In an emergency, it might provide life-saving drugs, which are distributed equally throughout the body, sometimes within seconds. For some conditions, a bolus injection allows consistent drug levels unattainable through oral medication or injection into muscles.
Certain medications can only be administered by injection, and many require dilution before being injected. Once drugs used in a bolus injection are properly mixed, a nurse typically times the rate of delivery using specific formulas for each type of drug. These drugs usually react best when given slowly over a prescribed period of time. The average rate is about 1 milliliter per minute.
Drugs administered via a bolus injection bypass enzymes in tissues and organs that might hinder absorption. The medication goes directly into a patient’s bloodstream and is not metabolized by the liver. In cases of acute or severe infection, antibiotics might immediately begin working after the injection.
This form of drug delivery might be used for patients unable to take oral medication because of physical problems or unconsciousness. It represents an alternative to intramuscular injections that could damage muscles. A bolus injection might cause less discomfort for a patient, especially if an intravenous line has already been established. If a new syringe is required, a special, small needle might prevent a collapsed vein.
Several complications might occur during a bolus injection, and negative reactions typically happen quickly. If certain drugs are introduced too quickly, a patient might go into shock. Drugs already injected into the bloodstream cannot be withdrawn if adverse effects appear from drug interactions or an allergy.
Any intravenous injection poses risks of air bubbles entering the vein. Blood clots might also form, especially if a foreign substance gets into the bloodstream. These problems might lead to thrombosis, a condition that restricts blood flow to a certain part of the body. Electrolyte and adrenaline levels might become unbalanced in some patients after a bolus injection.
This form of treatment might be harmful in patients with certain medical conditions. Patients with heart disorders might suffer adverse effects if drugs are introduced rapidly. An IV push might also cause harmful effects in patients with congested lungs or urination problems.