A nurse is preparing to administer diphenhydramine to a client who is to receive a blood transfusion. The nurse should explain that the purpose diphenhydramine is to prevent which of the following manifestations of a transfusion reaction?

A) Montelukast:
Montelukast is a leukotriene receptor antagonist used for the long-term control and prevention of asthma symptoms, but it is not typically used as a rescue medication to abort an ongoing asthma attack. Its onset of action is slower compared to short-acting beta agonists like albuterol.

B) Fluticasone:
Fluticasone is an inhaled corticosteroid medication used for the long-term control and management of asthma symptoms by reducing airway inflammation and preventing asthma exacerbations. It is not used as a rescue medication to abort an ongoing asthma attack but rather as a controller medication to prevent symptoms when used regularly over time.

C) Cromolyn:
Cromolyn is a mast cell stabilizer medication that is used for the prevention of asthma symptoms and exercise-induced bronchospasm. It is not typically used as a rescue medication to abort an ongoing asthma attack but rather as a controller medication to prevent symptoms when used regularly over time.

D) Albuterol.
Albuterol is a short-acting beta agonist bronchodilator commonly used as a rescue or reliever medication for acute asthma symptoms or to abort an ongoing asthma attack. It works quickly to relax the smooth muscles of the airways, leading to rapid bronchodilation and relief of symptoms such as wheezing, shortness of breath, and chest tightness. Albuterol is considered a first-line medication for relieving acute asthma symptoms and should be used as directed by a healthcare provider during an asthma exacerbation.

A. Decreased cardiac output: Inotropic medications are intended to improve cardiac function and increase cardiac output, so monitoring for signs of decreased cardiac output would be contrary to the expected therapeutic effect of these medications.

B. Increased afterload: Inotropic medications primarily affect the contractility of the heart muscle and do not typically have a direct effect on afterload (the force against which the heart must pump blood). While changes in afterload can occur as a secondary consequence of altered cardiac function, monitoring for signs of increased afterload would not be the primary focus after administering an inotropic medication.

C. Increased cardiac output.
Inotropic medications are drugs that affect the contractility of the heart muscle. They are often used in the management of shock to improve cardiac function and increase cardiac output. Therefore, after administering an inotropic medication, the nurse would monitor the patient for signs of increased cardiac output, such as improved peripheral perfusion, increased blood pressure, and resolution of signs and symptoms of shock.

D. Slowing of the heart rate: Inotropic medications can affect heart rate indirectly by altering cardiac output, but their primary effect is on contractility rather than heart rate. Monitoring for signs of bradycardia (slowing of the heart rate) may be appropriate in certain clinical situations, but it is not the primary consideration after administering an inotropic medication for shock.