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A 62-year-old woman is brought to the emergency room at a nearby hospital after being involved in a roadside accident in which she sustained severe chest trauma. Enroute to the hospital, morphine is administered for pain control. Upon arrival, the patient rapidly develops respiratory failure and requires intubation and mechanical ventilation. She is administered pancuronium in preparation for intubation but suddenly develops severe bronchospasm and wheezing. Her blood pressure also quickly falls from 120/80 mm Hg to 100/60 mm Hg. Which of the following best explains the most likely etiology of this complication?
A 45-year-old man is brought into the emergency department after he was hit by a car. The patient was intoxicated and walked into oncoming traffic. He is currently unconscious and has a Glasgow coma scale score of 3. The patient has been admitted multiple times for alcohol intoxication and pancreatitis. The patient is resuscitated with fluid and blood products. An initial trauma survey reveals minor scrapes and abrasions and pelvic instability. The patient’s pelvis is placed in a binder. After further resuscitation the patient becomes responsive and states he is in pain. He is given medications and further resuscitation ensues. One hour later, the patient complains of numbness surrounding his mouth and in his extremities. Which of the following is the most likely explanation of this patient’s current symptoms?
A 37-year-old woman is brought to the emergency department by police after being found naked outside a government building. She is accompanied by her husband who reports that she has been having "crazy" ideas. The patient's speech is pressured and she switches topics quickly from how she is going to be president one day to how she is going to learn 20 languages fluently by the end of the year. Upon further questioning, it is revealed that she has struggled with at least 2 depressive episodes in the past year. Her medical history is significant for hypertension, hyperlipidemia, gout, and chronic migraines. She was recently diagnosed with a urinary tract infection and given nitrofurantoin. She has also been taking indomethacin for an acute gout flare. Her other medications include atorvastatin, allopurinol, metoprolol, and acetazolamide. She is prescribed lithium and instructed to follow-up with a primary care physician. At a follow-up appointment, she complains of nausea, vomiting, and increased urinary frequency. On examination, she has a coarse tremor and diffuse hyperreflexia. Which of the following medications is most likely responsible for the patient's current presentation?
A 9-year-old boy is brought to the emergency department by his mother because of painful swelling in his right knee that started after he collided with another player during a soccer game. He has no history of serious illness except for an episode of prolonged bleeding following a tooth extraction a few months ago. Physical examination shows marked tenderness and swelling of the right knee joint. There are multiple bruises on the lower extremities in various stages of healing. Laboratory studies show a platelet count of 235,000/mm3, partial thromboplastin time of 78 seconds, prothrombin time of 14 seconds, and bleeding time of 4 minutes. The plasma concentration of which of the following is most likely to be decreased in this patient?
A 5-year-old boy is brought to the physician by his parents for the evaluation of an episode of loss of consciousness while he was playing soccer earlier that morning. He was unconscious for about 15 seconds and did not shake, bite his tongue, or lose bowel or bladder control. He has been healthy except for 1 episode of simple febrile seizure. His father died suddenly at the age of 34 of an unknown heart condition. The patient does not take any medications. He is alert and oriented. His temperature is 37°C (98.6°F), pulse is 95/min and regular, and blood pressure is 90/60 mm Hg. Physical examination shows no abnormalities. Laboratory studies are within normal limits. An ECG shows sinus rhythm and a QT interval corrected for heart rate (QTc) of 470 milliseconds. Which of the following is the most appropriate next step in treatment?
A 61-year-old woman presents to her physician with foot tingling, numbness, and pain. She describes her pain as constant and burning and gives it 5 out of 10 on the visual analog pain scale. She also recalls several falls due to the numbness in her feet. She was diagnosed with diabetes mellitus and diabetic retinopathy 5 years ago. Since then, she takes metformin 1000 mg twice daily and had no follow-up visits to adjust her therapy. Her weight is 110 kg (242.5 lb), and her height is 176 cm (5 ft. 7 in). The vital signs are as follows: blood pressure is 150/90 mm Hg, heart rate is 72/min, respiratory rate is 12/min, and the temperature is 36.6°C (97.9°F). The patient has increased adiposity in the abdominal region with stretch marks. The respiratory examination is within normal limits. The cardiovascular exam is significant for a bilateral carotid bruit. The neurological examination shows bilateral decreased ankle reflex, symmetrically decreased touch sensation and absent vibration sensation in both feet up to the ankle. The gait is mildly ataxic. The Romberg test is positive with a tendency to fall to both sides, and significant worsening on eye closure. Which of the following medications should be used to manage the patient’s pain?
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 previously healthy 52-year-old woman comes to the physician because of a 3-month history of chest pain on exertion. She takes no medications. Cardiopulmonary examination shows no abnormalities. Cardiac stress ECG shows inducible ST-segment depressions in the precordial leads that coincide with the patient's report of chest pain and resolve upon cessation of exercise. Pharmacotherapy with verapamil is initiated. This drug is most likely to have which of the following sets of effects? $$$ End-diastolic volume (EDV) %%% Blood pressure (BP) %%% Contractility %%% Heart rate (HR) $$$
A 35-year-old woman is brought to the emergency department 30 minutes after the onset of severe dyspnea. On arrival, she is unresponsive. Her pulse is 160/min, respirations are 32/min, and blood pressure is 60/30 mm Hg. CT angiography of the chest shows extensive pulmonary embolism in both lungs. She is given a drug that inhibits both thrombin and factor Xa. Which of the following medications was most likely administered?
A drug discovery team is conducting research to observe the characteristics of a novel drug under different experimental conditions. The drug is converted into the inactive metabolites by an action of an enzyme E. After multiple experiments, the team concludes that as compared to physiologic pH, the affinity of the enzyme E for the drug decreases markedly in acidic pH. Co-administration of an antioxidant A increases the value of Michaelis-Menten constant (Km) for the enzyme reaction, while co-administration of a drug B decreases the value of Km. Assume the metabolism of the novel drug follows Michaelis-Menten kinetics at the therapeutic dose, and that the effects of different factors on the metabolism of the drug are first-order linear. For which of the following conditions will the metabolism of the drug be the slowest?
Antiarrhythmic classification and mechanisms
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Class I antiarrhythmics (sodium channel blockers)
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Class II antiarrhythmics (beta blockers)
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Class III antiarrhythmics (potassium channel blockers)
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Class IV antiarrhythmics (calcium channel blockers)
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Other antiarrhythmic agents
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Antianginal drugs
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Positive inotropic agents
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Phosphodiesterase inhibitors
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Cardiac glycosides
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Vasopressors and inotropes
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Pulmonary hypertension therapies
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Peripheral vascular disease therapies
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