Which nursing intervention is essential for a patient with urinary retention?

The essential nursing intervention for a patient with urinary retention is performing a bladder scan. This procedure is crucial because it helps to assess the volume of urine retained in the bladder and determines the need for further interventions. Urinary retention can lead to complications such as increased bladder pressure, infections, and discomfort, so accurately measuring the amount of urine can guide treatment decisions.

By using a bladder scanner, the healthcare provider can visualize the bladder's contents non-invasively, which directly impacts how they manage the patient's condition—potentially necessitating catheterization if significant retention is observed. This immediate assessment can prevent further complications and provide the necessary information to develop an effective care plan tailored to the patient's needs.

The other interventions listed, while important in various clinical contexts, do not directly address the issue of urinary retention and thus are not as critical in this specific scenario. Monitoring blood sugar levels is unrelated to urinary retention, administering oxygen is pertinent to respiratory issues, and dietary modifications might aid in long-term management but do not address the immediate problem of urine retention.