This is a 35-year-old female with no regular medical care and no chronic medications, who was admitted with a diagnosis of acute appendicitis and underwent laparoscopic appendectomy about 2 hours ago. Per report, the intraoperative course was unremarkable. An arterial blood gas (ABG) is sent and comes back unremarkable as well, with normal lactic acid. She is febrile with a temperature of 38.5⁰C, heart rate of 110 bpm with frequent PVCs on the monitor, and blood pressure of 144/99 mmHg. She is diaphoretic and appears to be in distress but denies pain.

Of the following options, which diagnosis is MOST likely?

a. Anticholinergic overdose
b. Malignant hyperthermia
c. Pheochromocytoma
d. Thyroid storm

This condition matches the acute symptoms presented. Other options like anticholinergic overdose, malignant hyperthermia, or pheochromocytoma are less consistent with the patient’s presentation.

A 35-year-old female who recently underwent a laparoscopic appendectomy is presenting with distress signs such as a fever of 38.5°C, a heart rate of 110 bpm with frequent PVCs, and a blood pressure of 144/99 mmHg. Of the given options, the most likely diagnosis is a Thyroid storm (option d). This condition can present with hyperthermia, tachycardia, arrhythmias, and hypertension, which matches the patient's symptoms.

Other immediate post-operative complications like an infection or less likely anticholinergic overdose, malignant hyperthermia, or pheochromocytoma. Given the acute presentation and the symptoms, thyroid storm fits best.