A pharmacokinetic primer for intravenous nurses.
Traditionally, drug doses and intervals between doses have been empirically decided by prescribers. Doses and intervals were subsequently adjusted based on observed efficacy or toxic effects. In the absence of consistent clinical findings or when the disease being treated is episodic in nature, such as in the case of asthma or epilepsy, optimal dosing is difficult to achieve. An alternative approach is the adjustment of doses based on the concentration of drugs in plasma. This approach has come to be called therapeutic drug monitoring, or TDM. To make adjustment of doses more efficient, mathematical models have been developed that describe and predict drug concentrations in various body fluids. These mathematical models incorporate pharmacokinetic parameters, such as volume of distribution, absorption rate constant, and clearance, which, when known for a particular patient or group of patients, allow judicious adjustment of doses of drugs that might otherwise be ineffective. This article reviews the model most commonly used in TDM and explains the parameters associated with it. It also considers the importance of TDM in clinical practice and the role of the nurse in this aspect of patient care.
Korth-Bradley
J M
JM
D000368:Aged; D004358:Drug Therapy / Q000451:nursing*; D005260:Female; D005440:Fluid Therapy / Q000451:nursing*; D006801:Humans; D015233:Models, Statistical; D008991:Monitoring, Physiologic / Q000379:methods; D010599:Pharmacokinetics