A nurse caring for a patient with diabetes insipidus notes that the treatment involves antidiuretic hormone (ADH) replacement to help the kidneys absorb water and decrease urine output. The nurse remembers vasopressin should be avoided or used with caution in patients with coronary artery disease (CAD) because vasopressin can cause:

Choice A reason: High cortisol is not associated with SIADH. Cortisol excess occurs in conditions like Cushing’s syndrome, causing hyperglycemia and hypertension. SIADH involves excessive antidiuretic hormone, leading to water retention and dilutional hyponatremia, not cortisol elevation. Cortisol levels are unrelated to the pathophysiology of SIADH and would not be expected in lab results.

Choice B reason: Serum hypernatremia is incorrect, as SIADH causes water retention due to excessive antidiuretic hormone, diluting sodium levels. This leads to hyponatremia, not hypernatremia. Hypernatremia occurs in conditions like diabetes insipidus with water loss. SIADH’s mechanism of water retention lowers serum sodium, making this choice inconsistent with the condition.

Choice C reason: Increased serum osmolality is not expected in SIADH. Excessive antidiuretic hormone causes water retention, decreasing serum osmolality due to dilution. Normal or low osmolality triggers further ADH release, perpetuating hyponatremia. High osmolality is seen in dehydration or hypernatremia, not SIADH, where the opposite occurs due to water overload.

Choice D reason: Serum hyponatremia is characteristic of SIADH, where excessive antidiuretic hormone causes water retention, diluting serum sodium (normal: 135–145 mEq/L). This leads to hyponatremia, often below 135 mEq/L, causing symptoms like confusion or seizures. Lab results in SIADH typically show low sodium and low serum osmolality, confirming this as the expected finding.

Choice A reason: Obtaining vital signs every hour post-paracentesis monitors for complications like bleeding or hypovolemia, as the procedure removes peritoneal fluid, potentially causing hemodynamic instability. Frequent monitoring ensures early detection of hypotension, tachycardia, or other signs of complications, ensuring patient safety after this invasive procedure targeting spontaneous bacterial peritonitis.

Choice B reason: Having the patient void before paracentesis prevents bladder puncture, as a full bladder elevates the risk during needle insertion into the peritoneal cavity. Emptying the bladder ensures a safer procedure by reducing the risk of organ injury, a critical step in preparing for paracentesis to diagnose spontaneous bacterial peritonitis.

Choice C reason: Checking for a signed consent form is essential, as paracentesis is an invasive procedure requiring informed consent. This ensures the patient understands risks, benefits, and alternatives, adhering to ethical and legal standards. Confirming consent is a critical pre-procedure step to diagnose spontaneous bacterial peritonitis safely and appropriately.

Choice D reason: Encouraging early ambulation post-paracentesis is not standard, as patients may require monitoring for complications like bleeding or hypotension. Rest is typically advised initially to ensure stability. Ambulation may increase intra-abdominal pressure or risk complications, making it inappropriate in the immediate post-procedure care plan for this condition.

Choice E reason: Sending fluid for lab analysis is critical in paracentesis to diagnose spontaneous bacterial peritonitis. The fluid is tested for cell count, bacteria, and protein to confirm infection. This analysis guides antibiotic therapy and management, making it an essential component of the care plan to address the suspected bacterial infection.