Rate of infusion

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In pharmacokinetics, the rate of infusion (or dosing rate) refers not just to the rate at which a drug is administered, but the desired rate at which a drug should be administered to achieve a steady state of a fixed dose which has been demonstrated to be therapeutically effective.

Abbreviations include Kin, [1] K0, [2] or R0.

It can be calculated as the steady-state concentration in the plasma multiplied by the clearance:

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Intravenous therapy Medication administered into a vein

Intravenous therapy is a medical technique that delivers fluids, medications and nutrition directly into a person's vein. The intravenous route of administration is commonly used for rehydration or to provide nutrition for those who cannot consume food or water by mouth. It may also be used to administer medications or other medical therapy such as blood products or electrolytes to correct electrolyte imbalances. Attempts at providing intravenous therapy have been recorded as early as the 1400s, but the practice did not become widespread until the 1900s after the development of techniques for safe, effective use.

Route of administration Path by which a drug, fluid, poison, or other substance is taken into the body

A route of administration in pharmacology and toxicology is the path by which a drug, fluid, poison, or other substance is taken into the body.

Propofol Intravenous medication used in anaesthesia

Propofol, marketed as Diprivan, among other names, is a short-acting medication that results in a decreased level of consciousness and a lack of memory for events. Its uses include the starting and maintenance of general anesthesia, sedation for mechanically ventilated adults, and procedural sedation. It is also used for status epilepticus if other medications have not worked. It is given by injection into a vein, and the maximum effect takes about two minutes to occur and typically lasts five to ten minutes. Propofol is also used for medical assistance in dying in Canada.

Amiodarone

Amiodarone is an antiarrhythmic medication used to treat and prevent a number of types of irregular heartbeats. This includes ventricular tachycardia (VT), ventricular fibrillation (VF), and wide complex tachycardia, as well as atrial fibrillation and paroxysmal supraventricular tachycardia. Evidence in cardiac arrest, however, is poor. It can be given by mouth, intravenously, or intraosseously. When used by mouth, it can take a few weeks for effects to begin.

In pharmacology, bioavailability is a subcategory of absorption and is the fraction (%) of an administered drug that reaches the systemic circulation.

First pass effect

The first pass effect is a phenomenon of drug metabolism whereby the concentration of a drug, specifically when administered orally, is greatly reduced before it reaches the systemic circulation. It is the fraction of drug lost during the process of absorption which is generally related to the liver and gut wall. Notable drugs that experience a significant first-pass effect are imipramine, morphine, propranolol, buprenorphine, diazepam, midazolam, pethidine, tetrahydrocannabinol (THC), ethanol, cimetidine, lidocaine, chlorpromazine, and nitroglycerin (GTN). In contrast some drugs are enhanced in potency: for example, the effect of the most commonly considered active ingredient in cannabis, THC, is enhanced by transformation of a significant portion into 11-hydroxy-THC and thus achieves greater potency than the original THC.

Remifentanil synthetic opioid analgesic

Remifentanil is a potent, short-acting synthetic opioid analgesic drug. It is given to patients during surgery to relieve pain and as an adjunct to an anaesthetic. Remifentanil is used for sedation as well as combined with other medications for use in general anesthesia. The use of remifentanil has made possible the use of high-dose opioid and low-dose hypnotic anesthesia, due to synergism between remifentanil and various hypnotic drugs and volatile anesthetics.

Intraosseous infusion

Intraosseous infusion (IO) is the process of injecting directly into the marrow of a bone. This provides a non-collapsible entry point into the systemic venous system. This technique is used to provide fluids and medication when intravenous access is not available or not feasible. Intraosseous infusions allow for the administered medications and fluids to go directly into the vascular system. A comparison of intravenous (IV), intramuscular (IM), and intraosseous (IO) routes of administration concluded that the intraosseous route is demonstrably superior to intramuscular and comparable to intravenous administration. This route of fluid and medication administration is an alternative one to the preferred intravascular route when the latter cannot be established in a timely manner. Intraosseous infusions are utilized when trauma patients have compromised intravenous access and need immediate delivery of life saving fluids and medications.

Infusion pump

An infusion pump infuses fluids, medication or nutrients into a patient's circulatory system. It is generally used intravenously, although subcutaneous, arterial and epidural infusions are occasionally used.

Biological half-life of a biological substance such as medication is the time it takes from its maximum concentration (Cmax) to half maximum concentration in human body, and is denoted by the abbreviation .

Ifosfamide

Ifosfamide (IFO), sold under the brand name Ifex among others, is a chemotherapy medication used to treat a number of types of cancer. This includes testicular cancer, soft tissue sarcoma, osteosarcoma, bladder cancer, small cell lung cancer, cervical cancer, and ovarian cancer. It is administered by injection into a vein.

Bivalirudin

Bivalirudin (Bivalitroban), sold under the brand names Angiomax and Angiox and manufactured by The Medicines Company, is a direct thrombin inhibitor (DTI).

Treprostinil

Treprostinil, sold under the brand names Remodulin for infusion, Orenitram for oral, and Tyvaso for inhalation, is a vasodilator that is used for the treatment of pulmonary arterial hypertension. Treprostinil is a synthetic analog of prostacyclin (PGI2).

Pharmacokinetics, sometimes abbreviated as PK, is a branch of pharmacology dedicated to determine the fate of substances administered to a living organism. The substances of interest include any chemical xenobiotic such as: pharmaceutical drugs, pesticides, food additives, cosmetics, etc. It attempts to analyze chemical metabolism and to discover the fate of a chemical from the moment that it is administered up to the point at which it is completely eliminated from the body. Pharmacokinetics is the study of how an organism affects a drug, whereas pharmacodynamics (PD) is the study of how the drug affects the organism. Both together influence dosing, benefit, and adverse effects, as seen in PK/PD models.

In pharmacokinetics, a maintenance dose is the maintenance rate [mg/h] of drug administration equal to the rate of elimination at steady state. This is not to be confused with dose regimen, which is a type of drug therapy in which the dose [mg] of a drug is given at a regular dosing interval on a repetitive basis. Continuing the maintenance dose for about 4 to 5 half lives (t½) of the drug will approximate the steady state level. One or more doses higher than the maintenance dose can be given together at the beginning of therapy with a loading dose.

Clevidipine

Clevidipine is a dihydropyridine calcium channel blocker indicated for the reduction of blood pressure when oral therapy is not feasible or not desirable.

The elimination rate constantK or Ke is a value used in pharmacokinetics to describe the rate at which a drug is removed from the human system.

Self-administration is, in its medical sense, the process of a subject administering a pharmacological substance to themself. A clinical example of this is the subcutaneous "self-injection" of insulin by a diabetic patient.

The plateau principle is a mathematical model or scientific law originally developed to explain the time course of drug action (pharmacokinetics). The principle has wide applicability in pharmacology, physiology, nutrition, biochemistry, and system dynamics. It applies whenever a drug or nutrient is infused or ingested at a relatively constant rate and when a constant fraction is eliminated during each time interval. Under these conditions, any change in the rate of infusion leads to an exponential increase or decrease until a new level is achieved. This behavior is also called an approach to steady state because rather than causing an indefinite increase or decrease, a natural balance is achieved when the rate of infusion or production is balanced by the rate of loss.

Balanced anesthesia Anesthetic technique

Balanced anesthesia is a anesthetic method for surgical patients during their operation, which was proposed by John Lundy in 1926.The purpose of balanced anesthesia is not only to be less dangerous than using only one drug to make patients general anesthesia but also to minimise the potential adverse side effects which may cause by the anesthetic agents. The concept of balanced anesthesia is that applying two or more narcotic drugs or techniques in order to help patients to ease pain, relax the muscles and have autonomous reflection suppression. In other words, it is an anesthesia method to maintain stable vital signs. According to patients’ status of significant organs, general condition and compensatory capacity of bodies, anesthetist needs to make use of adequate types, appropriate amounts of agents and the accurate anesthesia method, which will promote the surgery be both successful and efficient in a further way.

References

  1. "Cp vs time - iv infusion".
  2. "Chapter 15.2 - Continuous IV Infusion - Steady State".