Which portion of the ECG is most valuable in diagnosing atrioventricular (AV) conduction disturbances?
a. P wave c. QRS complex
b. PR interval d. QT interval
B
The PR interval is an indicator of atrioventricular nodal function. The P wave represents atrial depolarization. The QRS complex represents ventricular depolarization, corresponding to phase 0 of the ventricular action potential. The QT interval is measured from the beginning of the QRS complex to the end of the T wave and indicates the total time interval from the onset of depolarization to the completion of repolarization.
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The nurse enters the client's room and asks the client a question from the doorway. What distance is this considered?
1. Public 2. Social 3. Personal 4. Intimate
The school nurse is helping to teach a science class about the anatomy of the eye. A student asks what the biggest part of the eye is. What would the school nurse reply?
A) "The posterior chamber." B) "The hyaloid membrane." C) "The ocular fundus." D) "The anterior chamber."
While instructing a patient on pain relief, the nurse uses the example of endorphins as endocrine hormones, which act locally at the site of injury. The nurse is explaining what route of hormone transport in the body?
1. paracrine method 2. direct release into the bloodstream 3. neuroendocrine route 4. nerve cell extension into the posterior pituitary
A client brings her mother to the office and states, "I'm worried about Mom; she takes aluminum hydroxide up to three times a day for this pain in her abdomen." Which statement about aluminum hydroxide is true?
1. Aluminum hydroxide can cause acute appendicitis and should be stopped immediately. 2. A transient abdominal discomfort occurs with the use of aluminum hydroxide and there is no need for concern. 3. It is safe to take aluminum hydroxide up to three times daily, due to its safety profile. 4. Antacids are for occasional use only; further investigation is warranted.