The nurse is caring for a large-for-gestational-age infant born to a client with diabetes mellitus.
What is the priority when assessing this infant?

Choice A rationale

Magnesium sulfate is a central nervous system depressant used to prevent seizures in preeclampsia. Being alert and oriented × 4 is a normal finding and indicates the drug is working at a therapeutic level without causing excessive CNS depression. Normal therapeutic serum magnesium is typically 4-7 mg/dL; this assessment finding indicates appropriate mentation.

Choice B rationale

Absent deep tendon reflexes (DTRs) indicate a loss of reflex excitability due to excessive neuromuscular blockade from hypermagnesemia, representing a major sign of magnesium toxicity. This finding suggests a dangerously high serum magnesium level (>8 mg/dL) and indicates immediate intervention is required to prevent profound respiratory depression and cardiac arrest.

Choice C rationale

A serum magnesium value of 6 mg/dL is within the normal therapeutic range of 4-7 mg/dL for preeclampsia management. This level is effective for seizure prophylaxis without typically causing severe signs of toxicity like respiratory depression or absent reflexes. Therefore, a level of 6 mg/dL does not warrant immediate discontinuation of the infusion.

Choice D rationale

A urine output of 10 mL/hr is significantly below the acceptable minimum of 30 mL/hr (or 100 mL/4 hours) for a client receiving magnesium sulfate. Magnesium is primarily excreted by the kidneys, and oliguria leads to drug accumulation, rapidly increasing the risk of magnesium toxicity. Decreased urine output requires immediate cessation of the infusion and potentially administration of an antidote.

Choice E rationale

A Glasgow Coma Scale (GCS) of 10 indicates a moderate neurological impairment, but it is not specific to magnesium toxicity. While a score below 8 would indicate severe CNS depression requiring immediate intubation, a score of 10 alone, without corroborating signs like absent DTRs or respiratory depression, does not immediately necessitate stopping the infusion, as it could relate to the underlying disease.

Choice F rationale

A respiratory rate of 10 breaths per minute is considered bradypnea and is a critical sign of impending respiratory depression, a life-threatening complication of severe magnesium toxicity. Magnesium depresses the respiratory center and paralyzes respiratory muscles at very high levels (>12 mg/dL). Infusion must be stopped immediately, and the antidote (calcium gluconate) must be prepared.

Choice A rationale

Peritonitis is a severe inflammation of the peritoneum, the membrane lining the abdominal cavity, usually due to bacterial contamination from a perforated viscus or the uterus. While a serious complication of advanced puerperal infection, peritonitis presents with generalized severe abdominal rigidity, rebound tenderness, and high fever, not just an increase in localized perineal pain, which is the key symptom described.

Choice B rationale

Thrombophlebitis (or superficial vein thrombosis) involves inflammation and clotting in a vein, most commonly in the legs post-delivery. It presents with localized warmth, redness, swelling, and pain along the course of the affected vein in the calf or thigh, not primarily with increased localized pain in the perineal region, which is the anatomical area described in the report.

Choice C rationale

Infection of the perineum (often related to an episiotomy, laceration repair, or hematoma) is highly likely given the combination of a prolonged rupture of membranes (a risk factor) and the specific complaint of increasing perineal pain two days postpartum. Infection leads to localized inflammation, edema, purulent drainage, and increased pain at the perineal wound site, matching the client's symptoms and risk profile.

Choice D rationale

Endometritis is an infection of the uterine lining (endometrium), a common postpartum complication, especially after prolonged rupture of membranes. Classic signs include fever, uterine subinvolution, and foul-smelling lochia, often accompanied by lower abdominal or uterine tenderness, but increasing perineal pain points more specifically to a localized wound infection or abscess in that area.