A client with a history of deep vein thrombosis (DVT) is receiving a continuous IV heparin infusion. The nurse notes that the client’s activated partial thromboplastin time (aPTT) is 120 seconds. Which action should the nurse take? Reference Range: aPTT [25 to 35 seconds, therapeutic range for heparin 1.5 to 2.5 times baseline, approximately 38 to 88 seconds].

Choice A reason: Dry skin and inelastic turgor reflect dehydration in DI from antidiuretic hormone deficiency, causing water loss. This is less urgent than hypernatremia (185 mEq/L), which dehydrates brain cells, risking seizures or coma, requiring immediate fluid correction to prevent neurological damage in this critical condition.

Choice B reason: Tachycardia (110 beats/minute) compensates for hypovolemia in DI, where water loss reduces preload, triggering sympathetic activation. This is less critical than hypernatremia (185 mEq/L), which causes cerebral dehydration, necessitating urgent hypotonic fluids to prevent neurological complications, making heart rate secondary.

Choice C reason: Serum sodium of 185 mEq/L indicates severe hypernatremia in DI, where water loss concentrates sodium, dehydrating neurons and risking seizures or coma. Immediate IV hypotonic fluids (e.g., 5% dextrose) correct osmolarity, preventing life-threatening cerebral complications, addressing the urgent pathophysiological crisis in DI.

Choice D reason: Polyuria and thirst are hallmark DI symptoms from water loss but expected and less urgent than hypernatremia (185 mEq/L), which threatens neurological function via osmotic brain injury. Correcting sodium is critical to prevent seizures, making these symptoms secondary to urgent electrolyte management.

Choice A reason: Persistent pain after Herpes zoster suggests postherpetic neuralgia (PHN), a neuropathic condition from varicella-zoster virus damaging sensory nerves. Assessing pain intensity, location, and characteristics guides treatment with analgesics or anticonvulsants like gabapentin. This step differentiates PHN from other causes, ensuring targeted therapy to alleviate nerve pain and improve quality of life.

Choice B reason: Checking shingles vaccination status is irrelevant for current pain, as the client already had Herpes zoster. Vaccination prevents initial infection but does not treat PHN, which results from nerve damage during active infection. Pain assessment is critical to address neuropathic symptoms caused by viral-induced sensory nerve dysfunction, making this less urgent.

Choice C reason: A mental status exam evaluates cognition but is not indicated for PHN, a physiological condition from nerve damage, not a cognitive issue. Pain is neuropathic, driven by damaged sensory neurons, not psychological factors. Assessing pain directly addresses the client’s complaint, guiding treatment for nerve-related discomfort, making this action inappropriate.

Choice D reason: Teaching about phantom pain is incorrect, as phantom pain occurs post-amputation, not after shingles. PHN involves persistent nerve pain in the affected dermatome due to viral nerve damage. Misdiagnosing this could delay proper management, as pain assessment is needed to confirm PHN and initiate therapies like gabapentin, not phantom pain education.