What is the fastest route for medication administration?

Choice A reason: This is incorrect. Miosis is the constriction of the pupils, which can also be caused by morphine, but it is not a life-threatening side effect. Miosis occurs because morphine stimulates the parasympathetic nervous system, which controls the muscles that constrict the pupils¹.

Choice B reason: This is incorrect. Sedation is the state of being calm, relaxed, and sleepy, which can also be caused by morphine, but it is not a life-threatening side effect. Sedation occurs because morphine depresses the central nervous system, which reduces the activity of the brain and the body.

Choice C reason: This is correct. Respiratory depression is the slowing down of breathing, which can be a life-threatening side effect of morphine. Respiratory depression occurs because morphine depresses the respiratory center in the brainstem, which regulates the rate and depth of breathing. If the breathing becomes too slow or shallow, the patient may not get enough oxygen and may lose consciousness or die.

Choice D reason: This is incorrect. Euphoria is the feeling of intense happiness, pleasure, or wellbeing, which can also be caused by morphine, but it is not a life-threatening side effect. Euphoria occurs because morphine stimulates the reward system in the brain, which releases dopamine, a neurotransmitter that causes positive emotions.

Choice A reason: Vasodilation is not the primary therapeutic effect of atropine in this scenario. Atropine is a medication that blocks the action of acetylcholine, a neurotransmitter that stimulates the parasympathetic nervous system. Atropine can cause vasodilation by inhibiting the muscarinic receptors on the blood vessels, which normally cause vasoconstriction. However, this effect is not significant or consistent, and it does not improve the symptoms of bradycardia, which is a slow heart rate that can cause dizziness, fatigue, or fainting. The nurse should monitor the blood pressure and the peripheral pulses of the patient after administering atropine.

Choice B reason: Bronchodilation is not the primary therapeutic effect of atropine in this scenario. Atropine is a medication that blocks the action of acetylcholine, a neurotransmitter that stimulates the parasympathetic nervous system. Atropine can cause bronchodilation by inhibiting the muscarinic receptors on the bronchial smooth muscle, which normally cause bronchoconstriction. However, this effect is not relevant or beneficial for the patient with symptomatic bradycardia, who does not have any respiratory problems. The nurse should assess the respiratory rate and the breath sounds of the patient after administering atropine.

Choice C reason: Increase in heart rate is the primary therapeutic effect of atropine in this scenario. Atropine is a medication that blocks the action of acetylcholine, a neurotransmitter that stimulates the parasympathetic nervous system. Atropine can increase the heart rate by inhibiting the muscarinic receptors on the sinoatrial node and the atrioventricular node, which normally slow down the heart rate. This effect is desirable and beneficial for the patient with symptomatic bradycardia, who has a slow heart rate that can cause dizziness, fatigue, or fainting. The nurse should monitor the electrocardiogram and the heart rate of the patient after administering atropine.

Choice D reason: Diuresis is not the primary therapeutic effect of atropine in this scenario. Atropine is a medication that blocks the action of acetylcholine, a neurotransmitter that stimulates the parasympathetic nervous system. Atropine can cause diuresis by inhibiting the muscarinic receptors on the bladder, which normally promote urination. However, this effect is not important or helpful for the patient with symptomatic bradycardia, who does not have any urinary problems. The nurse should measure the urine output and the specific gravity of the patient after administering atropine.