Which disease causes a classic butterfly rash over cheeks and bridge of nose (malar rash), which looks like a sunburn?

Choice A rationale

A ventricular pacemaker is designed to pace the ventricles, not the atria. Therefore, a pacemaker spike appearing before each P wave would indicate atrial pacing, which is not the primary function of a ventricular pacemaker. P waves represent atrial depolarization, and a ventricular pacemaker's stimulus is delivered to the ventricles to initiate a QRS complex.

Choice B rationale

A pacemaker spike appearing after each QRS complex suggests either oversensing, undersensing with competitive rhythms, or a malfunction. The purpose of a pacemaker spike is to *initiate* depolarization, not to follow it. If the spike occurs after the QRS, it indicates that the ventricle has already depolarized, and the spike is not contributing to ventricular contraction.

Choice C rationale

A pacemaker spike appearing with each T wave would be inappropriate and potentially dangerous. The T wave represents ventricular repolarization, a vulnerable period during which an electrical stimulus can induce life-threatening arrhythmias like ventricular fibrillation (R-on-T phenomenon). Pacing should occur before ventricular depolarization, not during repolarization.

Choice D rationale

A ventricular pacemaker functions by delivering an electrical impulse to the ventricle when its intrinsic rate falls below a programmed threshold. This impulse, seen as a pacemaker spike on the ECG, should precede ventricular depolarization, thus initiating a QRS complex. This indicates that the pacemaker is effectively stimulating ventricular contraction at the appropriate time.

Choice A rationale

Night sweats are a common manifestation of tuberculosis and certain malignancies, but they are not a primary or typical indicator of pneumonia in older adults. While systemic inflammation can occur, the diaphoresis associated with pneumonia is often general and less specific to nighttime periods.

Choice B rationale

Confusion, or an acute change in mental status, is a very common and often the presenting manifestation of pneumonia in older adult clients. This is due to systemic inflammation, hypoxemia, and decreased cerebral perfusion, making the brain more vulnerable to physiological changes than in younger individuals.

Choice C rationale

Tachycardia, not bradycardia, is a more common manifestation of pneumonia in older adults. The body compensates for hypoxemia and increased metabolic demands by increasing heart rate to improve oxygen delivery to tissues. Bradycardia would be atypical and might suggest other underlying conditions.

Choice D rationale

A narrowed pulse pressure, which is the difference between systolic and diastolic blood pressure, is often an indicator of conditions like cardiac tamponade or severe hypovolemia. In pneumonia, while blood pressure can fluctuate, a consistently narrowed pulse pressure is not a specific or common finding.