Le blues du méthylène : prévenir les réactions indésirables aux médicaments non anesthésiques

Abstract

NE of the main focuses in the training of anesthesiologists is the art of applied clinical pharmacology. The many and diverse drugs that we use daily have near instantaneous actions, satisfying the need for “immediate gratification” that attracted many of us to this field. We are also well trained in anticipating and treating the unintended effects of our pharmacologic armamentarium. These range from common side effects such as hypotension or hypoventilation, to sporadic reactions such as anaphylaxis. To complicate matters, the incidence of adverse drug reactions is influenced by factors such as age, ethnicity, pre-existing medical conditions and concurrent drug therapy. For example, we can predict that elderly, diabetic or hypertensive patients may have an exaggerated blood pressure response to induction agents, or that angiotensin converting enzyme inhibitor and beta adrenergic blocking drugs may alter the hemodynamic response to anesthetics. In this way, we constantly anticipate reactions and tailor our anesthetic techniques to account for these factors. Similarly, many patients present with a history of allergic reactions to medications; these drugs can easily be avoided. We can also predict a higher incidence of such reactions in patients with other known sensitivities, such as the increased incidence of reactions to non-steroidal anti-inflammatory drugs (NSAIDs) in patients with allergy to aspirin, 1 or an alteration in response to meperidine in patients receiving monoamine oxidase inhibitors. 2 A family history of malignant hyperthermia or cholinesterase deficiency prompts special precautions due to the known genetic transmission of these traits. Frequently, it is not the drug compound that is responsible for reactions, but rather preservatives in the preparations, such as local anesthetics with the preservatives methylparaben in patients with a history of sunscreen allergy, and sodium metabisulfite in patients with sulfite allergy. 3 There is, however, an increasing demand on the anesthesiologist to administer (and thereby assume responsibility for) a variety of non-anesthetic drugs. In addition, drugs, or other potential allergens such as disinfectant preparations, are frequently administered by surgeons and nurses, with the expectation that the “resuscitation expert” at the head of the table will deal with any potential reactions. A list of commonly used agents that fall into this category is provided in the Table; this list is not comprehensive, and there are new drugs with potential reactions being added almost daily.