Which vaccine is now recommended for the immunization of all newborns?

The correct answer is choice B. Reduce gastric acid production.

Choice A rationale:

Preventing reflux is not the primary purpose of prescribing a histamine receptor antagonist. Histamine receptor antagonists work by reducing gastric acid production, which in turn can help alleviate symptoms of gastroesophageal reflux disease (GERD). They do not directly prevent the physical reflux of stomach contents into the esophagus.

Choice B rationale:

The primary purpose of prescribing a histamine receptor antagonist for an infant diagnosed with gastroesophageal reflux is to reduce gastric acid production. Histamine stimulates acid secretion in the stomach, and these medications (e.g., ranitidine, famotidine) block histamine receptors on stomach cells, leading to decreased acid secretion. This helps reduce the acidity of stomach contents that could contribute to esophageal irritation in GERD.

Choice C rationale:

Preventing hematemesis (vomiting blood) is not a primary action of histamine receptor antagonists. While reducing gastric acid production might indirectly help prevent complications such as bleeding due to irritation and inflammation of the esophagus, it's not the main purpose of these medications.

Choice D rationale:

Increasing gastric acid production is the opposite of the intended effect of histamine receptor antagonists. These medications are specifically used to decrease gastric acid production and provide relief from conditions where excess acid is causing problems, such as GERD.

The correct answer is choice A. The cuff bladder covers 50% to 66% of the length of the upper arm.

Choice A rationale:

Selecting a blood pressure cuff with a bladder that covers 50% to 66% of the length of the upper arm is the appropriate criterion for determining the cuff size for a 2-year-old boy. This range ensures accurate blood pressure measurement by ensuring a proper fit on the arm. If the cuff bladder is too small or too large, it can result in inaccurate readings.

Choice B rationale:

The label "toddler" on the cuff might be helpful in identifying the intended age group, but it doesn't provide precise measurements for cuff sizing. Relying solely on a label might not account for variations in arm sizes within the toddler age group.

Choice C rationale:

The cuff bladder width being 40% of the circumference of the upper arm might not be as accurate as the length-based criterion. A cuff that fits the arm's length is more critical in ensuring proper inflation and accurate blood pressure measurement.

Choice D rationale:

The cuff bladder length covering 80% to 100% of the circumference of the upper arm might result in an excessively large cuff for a 2-year-old, which can lead to inaccurate readings. Length-based sizing is more appropriate for accuracy in this scenario.