Which patient is at higher risk for urinary retention among newly admitted clients?

The patient who is taking diphenhydramine is at higher risk for urinary retention due to the medication's anticholinergic properties. Diphenhydramine is an antihistamine that can cause a range of side effects, including the relaxation of smooth muscle and decreased bladder contraction. This can lead to difficulty in urination and urinary retention, particularly in individuals who may be more sensitive to these effects, such as a school-age child.

In contrast, while surgery recovery and diabetes can both have implications for bladder function, they do not inherently predispose a patient to urinary retention in the same direct way that anticholinergic medications do. For example, a teenager recovering from surgery may experience changes in bladder function due to factors like pain or medication but is not specifically at high risk from urinary retention without the influence of such a drug. Similarly, an adult client with diabetes may face complications with bladder function related to nerve damage over the long term, but this condition is not an immediate risk factor as seen with the use of diphenhydramine. A school-age child with asthma is also unlikely to face urgent concerns regarding urinary retention related to their condition or common treatments.