Author Question: Three days after an anterior wall MI, a patient is in the critical care unit. The patient is ... (Read 94 times)

littleanan · **on:** Jun 25, 2018

Three days after an anterior wall MI, a patient is in the critical care unit. The patient is receiving oxygen at 4 L/min by nasal cannula; nitroglycerin paste, 1-inch q6h; and Lopressor 25 mg PO q12h.

The monitor shows that the patient is beginning to have premature ventricular contractions (PVCs). Over the course of the next several hours, the PVCs increase in frequency to more than 15 per minute, with occasional runs of multifocal bigeminal PVCs. The patient's vital signs follow: heart rate, 84 beats/min; sinus rhythm with described PVCs; blood pressure, 124/68 mm Hg; respirations, 20 breaths/min; and SpO2, 92. Laboratory values are blood pH, 7.44; potassium, 4.4 mEq/L; and magnesium, 1.0 mEq/L. Which of the following, if ordered, would be inappropriate for this patient?

a. Lidocaine 100 mg IV push
b. Increase oxygen to 6 L/min by nasal cannula
c. Potassium chloride 40 mEq in 250 mL 0.9 saline IV piggyback over a 4-hour period
d. Magnesium sulfate 2 g IV piggyback over a 2-hour period

Question 2

A patient states that he has been taking Demerol 50 mg tablets four times a day for the past 5 years, but they are not working like they use to. The nurse is concerned that the patient has developed

a. addiction to Demerol.
b. physical dependence and tolerance.
c. physical dependence and addiction.
d. a method to withdraw himself off the medication.

samiel-sayed · **Reply #1 on:** Jun 25, 2018

Answer to Question 1

C
PVCs are initially controlled by administering oxygen to reduce myocardial hypoxia and by correcting acid-base or electrolyte imbalances. In the setting of an acute myocardial infarction, premature ventricular contractions (PVCs) are pharmacologically treated if they have the following characteristics: frequent (>6/min), closely coupled (R-on-T phenomenon), multiform shapes, and occurrence in bursts of three or more, increasing the risk of sustained ventricular tachycardia. The potassium level is within normal limits and replacement is not warranted. All other interventions listed are appropriate for this patient.

Answer to Question 2

B
Addiction is defined by a pattern of compulsive drug use that is characterized by an incessant longing for an opioid and the need to use it for effects other than pain relief. Tolerance is defined as a diminution of opioid effects over time. Physical dependence and tolerance to opioids may develop if the medication is given over a long period. Physical dependence is manifested by withdrawal symptoms when the opioid is abruptly stopped.