Correct Answer: C

Rationale: The correct answer is a patient with a history of ventricular tachycardia and syncopal episodes. An automatic internal cardioverter-defibrillator is used to deliver an electric shock to the heart to terminate episodes of ventricular tachycardia and ventricular fibrillation. These patients are at high risk of life-threatening arrhythmias, which may result in syncope. Patients with atrial tachycardia and fatigue (Choice D) would not typically require an implantable cardioverter-defibrillator as their primary issue is related to atrial arrhythmias. Patients who have had a myocardial infarction without cardiac muscle damage (Choice A) or postoperative coronary bypass patients recovering on schedule (Choice B) are not necessarily at high risk for ventricular arrhythmias and would not be the primary candidates for an implantable cardioverter-defibrillator.

Correct Answer: D

Rationale: IgG is the only immunoglobulin that can cross the placental barrier, providing passive immunity to the fetus. About 70-80% of the immunoglobulins in the blood are IgG. Specific IgG antibodies are generated after an initial exposure to an antigen, offering long-term protection against microorganisms. IgG antibodies are critical for protecting the fetus as they can be rapidly reproduced upon re-exposure to the same antigen. IgA is primarily found in mucosal areas, IgD is involved in antigen recognition, and IgE is associated with allergic reactions, but they do not provide the same level of protection to the fetus as IgG.

Correct Answer: B

Rationale: Increased intracranial pressure after head trauma can lead to serious complications. Repeated vomiting is a concerning sign as it can indicate stimulation of the vomiting center within the brainstem due to increased pressure. This can be an early indicator of raised intracranial pressure and the need for urgent medical intervention. Bulging anterior fontanel may not be immediately apparent in a 4-year-old child and is more common in infants. Signs of sleepiness at a particular time of day are not specific to increased intracranial pressure. Inability to read short words from a distance of 18 inches may indicate vision problems but is not directly related to intracranial pressure.

Correct Answer: D

Rationale: A platelet count of 25,000/microliter indicates severe thrombocytopenia, which increases the risk of bleeding. It is crucial to initiate bleeding precautions, including regularly checking for signs of bleeding such as examining urine and stool for blood. Monitoring for fever every 4 hours (Choice A) should be included for neutropenic precautions, not specifically related to platelet count. Requiring visitors to wear respiratory masks and protective clothing (Choice B) is more relevant for patients with airborne precautions. Considering transfusion of packed red blood cells (Choice C) is not indicated for low platelet count but is more appropriate for managing anemia or low hemoglobin levels.

Correct Answer: C

Rationale: Petechiae on the soft palate are not a typical finding in scarlet fever. Scarlet fever is caused by group A Streptococcus bacteria, often presenting with a strawberry tongue, red and swollen pharynx, and a sandpaper-like rash. The presence of petechiae on the soft palate is more commonly associated with conditions like rubella rather than scarlet fever. Therefore, this description is not correct in the context of scarlet fever.