Malignant hyperthermia — MCQs

A 70-year-old man presents to his primary care physician for a general checkup. He states that he has been doing well and taking his medications as prescribed. He recently started a new diet and supplement to improve his health and has started exercising. The patient has a past medical history of diabetes, a myocardial infarction, and hypertension. He denies any shortness of breath at rest or with exertion. An ECG is performed and is within normal limits. Laboratory values are ordered as seen below. Serum: Na+: 139 mEq/L Cl-: 100 mEq/L K+: 6.7 mEq/L HCO3-: 25 mEq/L Glucose: 133 mg/dL Ca2+: 10.2 mg/dL Which of the following is the most likely cause of this patient's presentation?

A 59-year-old female presents to the emergency department after a fall. She reports severe pain in her right hip and an inability to move her right leg. Her past medical history is notable for osteoporosis, rheumatoid arthritis, and has never undergone surgery before. The patient was adopted, and her family history is unknown. She has never smoked and drinks alcohol socially. Her temperature is 98.8°F (37.1°C), blood pressure is 150/90 mmHg, pulse is 110/min, and respirations are 22/min. Her right leg is shortened, abducted, and externally rotated. A radiograph demonstrates a displaced femoral neck fracture. She is admitted and eventually brought to the operating room to undergo right hip arthroplasty. While undergoing induction anesthesia with inhaled sevoflurane, she develops severe muscle contractions. Her temperature is 103.4°F (39.7°C). A medication with which of the following mechanisms of action is indicated in the acute management of this patient’s condition?

A 32-year-old man is brought to the emergency department after he was found unresponsive on the street. Upon admission, he is lethargic and cyanotic with small, symmetrical pinpoint pupils. The following vital signs were registered: blood pressure of 100/60 mm Hg, heart rate of 70/min, respiratory rate of 8/min, and a body temperature of 36.0°C (96.8°F). While being assessed and resuscitated, a sample for arterial blood gas (ABG) analysis was taken, in addition to the following biochemistry tests: Laboratory test Serum Na+ 138 mEq/L Serum Cl- 101 mEq/L Serum K+ 4.0 mEq/L Serum creatinine (SCr) 0.58 mg/dL Which of the following values would you most likely expect to see in this patient’s ABG results?

Two-hours into recovery from general anesthesia for an orthopedic fracture, a 34-year-old woman develops fever and masseter muscle rigidity with lockjaw. She has no history of a similar episode. She has no history of serious illness and takes no medications. She appears confused. In the recovery room, her blood pressure is 78/50 mm Hg, the pulse is 128/min, the respirations are 42/min, and the temperature is 40.3°C (104.5°F). Cardiopulmonary examination shows no abnormalities. Laboratory studies show: Serum Na+ 145 mEq/L K+ 6.5 mEq/L Arterial blood gas on room air pH 7.01 PCO2 78 mm Hg HCO3− 14 mEq/L PO2 55 mm Hg The patient is reintubated. Which of the following is the most appropriate next step in pharmacotherapy?

A 35-year-old male patient is brought into the emergency department by emergency medical services. The patient has a history of schizophrenia and is on medication per his mother. His mother also states that the dose of his medication was recently increased, though she is not sure of the specific medication he takes. His vitals are HR 110, BP 170/100, T 102.5, RR 22. On exam, he cannot respond to questions and has rigidity. His head is turned to the right and remains in that position during the exam. Labs are significant for a WBC count of 14,000 cells/mcL, with a creatine kinase (CK) level of 3,000 mcg/L. What is the best treatment for this patient?

A 33-year-old man presents to the emergency department acutely confused. The patient was found down at a local construction site by his coworkers. The patient has a past medical history of a seizure disorder and schizophrenia and is currently taking haloperidol. He had recent surgery 2 months ago to remove an inflamed appendix. His temperature is 105°F (40.6°C), blood pressure is 120/84 mmHg, pulse is 150/min, respirations are 19/min, and oxygen saturation is 99% on room air. Physical exam is notable for a confused man who cannot answer questions. His clothes are drenched in sweat. He is not making purposeful movements with his extremities although no focal neurological deficits are clearly apparent. Which of the following is the most likely diagnosis?

A 55-year-old man with chronic pain on high-dose opioids (120 mg oral morphine equivalents daily) requires major spine surgery. Intraoperatively, he requires escalating doses of fentanyl with poor pain control. Postoperatively, his pain remains severe (10/10) despite maximum conventional multimodal analgesia including IV hydromorphone PCA, acetaminophen, and ketorolac. He becomes increasingly agitated and tachycardic. Evaluate the most comprehensive pain management strategy addressing the underlying pathophysiology.

A 70-year-old man with severe aortic stenosis (valve area 0.6 cm², mean gradient 55 mmHg) develops acute cholecystitis requiring surgery. He is symptomatic with exertional angina and dyspnea. Cardiology recommends TAVR before surgery, but the patient has signs of gallbladder perforation. The surgical team debates timing of interventions. Evaluate the optimal management strategy weighing cardiac and surgical risks.

A 42-year-old woman with a history of multiple anesthetic complications presents for elective surgery. Previous records indicate awareness during general anesthesia twice, prolonged paralysis after succinylcholine requiring 6 hours of ventilation, and a sibling with fatal anesthetic complication involving hyperthermia and rhabdomyolysis. Evaluate the comprehensive anesthetic plan that addresses all potential complications.

A 65-year-old man develops postoperative delirium on day 2 after open AAA repair. He is agitated, pulling at his lines, and has waxing-waning confusion. His vital signs are stable, and laboratory values including sodium, glucose, and calcium are normal. He received 4 mg of morphine IV 2 hours ago for pain. Analyze the most appropriate pharmacologic intervention.