Tüm alıştırma soruları

A 62-year-old woman is evaluated in the surgical intensive care unit for a new-onset fever. She underwent a complex exploratory laparotomy for a perforated viscus 6 days ago. Postoperatively, she required significant fluid resuscitation and vasopressor support, prompting the placement of a central venous catheter in the right internal jugular vein. She has been weaning off support, but today her temperature is 38.9°C (102°F), blood pressure is 94/62 mmHg, and heart rate is 114/min. The catheter insertion site shows no erythema or purulent drainage. Leukocyte count is 16,500/mm³. Paired blood cultures drawn from the central line and a peripheral vein are pending. The medical director of the ICU is currently implementing a quality improvement initiative to decrease the incidence of this patient's suspected hospital-acquired condition. Which of the following practices should be strictly enforced as part of the evidence-based insertion bundle to most effectively prevent this complication?

A multidisciplinary tumor board is reviewing the case of a 52-year-old man with locally advanced pancreatic adenocarcinoma. The lead surgical oncologist advocates for immediate surgical resection, stating it offers the best chance for survival. The medical oncologist strongly disagrees, pointing out that recent imaging demonstrates subtle superior mesenteric artery encasement, making the tumor unresectable upfront, and insists on neoadjuvant chemotherapy. The surgeon becomes dismissive, stating the medical oncologist is being 'overly cautious,' and announces he will schedule the patient for the operating room the following morning. The radiologist in the room agrees with the medical oncologist's assessment but remains silent. The medical oncologist, who has already clearly voiced the clinical concern and discomfort with the operative plan once, believes that proceeding to surgery will result in severe morbidity and an incomplete resection. Which of the following is the most appropriate next step for the medical oncologist to ensure patient safety?

A 48-year-old woman is hospitalized for a severe, rapidly spreading necrotizing soft tissue infection of her right lower extremity. Her past medical history includes type 1 diabetes mellitus and end-stage renal disease on hemodialysis. The surgical team recommends an emergent right above-knee amputation as a life-saving intervention. The patient is awake, alert, and oriented. She accurately repeats the diagnosis, acknowledges that without the surgery she will likely die from systemic infection within days, but calmly refuses the procedure. She states, 'I have endured enough medical interventions over the years and do not want to live with an amputation.' The attending physician thoroughly evaluates her and concludes she fully understands her situation and the consequences of her choice. Shortly after, the patient's oldest son, who is named as her healthcare proxy in a valid advance directive, arrives at the hospital. He is distressed and demands that the surgical team operate immediately. He argues, 'She is just overwhelmed and not thinking straight right now. Furthermore, she has never been evaluated by a judge or declared legally competent to make a decision that will end her life.' Her blood pressure is 105/65 mm Hg and pulse is 98/min. Which of the following is the most appropriate next step in management?

Match each clinical adjustment in diagnostic testing strategy or patient population with its direct mathematical consequence on the test's performance characteristics.

A local public health department is investigating the risk of new-onset type 2 diabetes mellitus in a cohort of night-shift workers at a large manufacturing plant. At the beginning of the prospective study, $315$ workers are enrolled. Baseline screening reveals that $15$ workers already have a diagnosis of type 2 diabetes; they are excluded from the longitudinal follow-up. The remaining workers are followed for $5$ years.

The study yields the following follow-up data:
- $120$ workers complete the entire $5$-year study without developing diabetes.
- $30$ workers develop diabetes at exactly $24$ months into the study.
- $30$ workers develop diabetes at exactly $48$ months into the study.
- $120$ workers relocate and are lost to follow-up at exactly $42$ months into the study. None of these workers developed diabetes prior to their departure.

Based on the information above, what is the incidence rate of type 2 diabetes in this cohort, expressed per $1,000$ person-years?

A 32-year-old man presents to the primary care clinic with a 1-week history of a painless ulcer on his penis. He has no other symptoms. He is married but admits to a recent unprotected sexual encounter with a new female partner while traveling for work. Physical examination reveals a 1-cm, firm, non-tender ulcer with raised borders on the glans penis and bilateral, non-tender inguinal lymphadenopathy. A rapid plasma reagin (RPR) test is positive, and a fluorescent treponemal antibody absorption (FTA-ABS) test is also positive. The physician plans to administer intramuscular benzathine penicillin G and counsels the patient on the diagnosis of primary syphilis and the importance of partner notification. The patient becomes visibly anxious and states, "You cannot tell anyone about this, especially not the government or my wife. I am invoking my right to medical confidentiality." Which of the following is the most appropriate next step in management?

Match the following clinical research scenarios with their corresponding epidemiological study design.

A 62-year-old man with a well-documented history of severe alcohol use disorder is brought to the emergency department by EMS after being found sleeping on a park bench. The triage notes state, "Intoxicated, smells of alcohol, uncooperative." The assessing physician evaluates the patient, noting lethargy, slurred speech, and ataxia, and establishes a working diagnosis of acute alcohol intoxication. A non-contrast head CT is obtained due to a small scalp abrasion. The scan reveals a small subdural hematoma. The physician briefly views the imaging and documents, "likely chronic subdural hematoma, incidental and non-contributory to current acute intoxication state," without comparing it to any prior neuroimaging. The patient is placed in the observation unit to metabolize the alcohol but becomes unresponsive three hours later due to uncal herniation. The physician's specific act of rationalizing the objective CT scan findings as 'incidental' in order to maintain the preconceived diagnosis of acute alcohol intoxication best illustrates which of the following cognitive errors?

A 34-year-old physician completes the daily physical examination of a patient hospitalized with disseminated varicella-zoster virus (VZV) infection. The patient is housed in a negative-pressure airborne infection isolation room. The physician is wearing appropriate personal protective equipment (PPE), including an N95 respirator, a face shield, a disposable fluid-resistant gown, and non-sterile gloves. The physician now prepares to exit the room.

Arrange the following steps for doffing the personal protective equipment in the correct chronological sequence according to standard infection control and patient safety guidelines.

A 32-year-old man presents to the clinic with an intermittent low-grade fever, fatigue, and a new heart murmur. The physician suspects infective endocarditis. Based on the clinical presentation and local epidemiological data, the physician estimates the patient's pretest probability for the disease to be $10\%$. A novel rapid serum biomarker assay is performed, which has a reported positive likelihood ratio ($LR^+$) of $9.0$ and a negative likelihood ratio ($LR^-$) of $0.2$. The test result comes back positive. Which of the following is the best estimate of this patient's post-test probability of having infective endocarditis?

A 62-year-old man with advanced amyotrophic lateral sclerosis is evaluated in the progressive care unit. He was admitted two days ago for worsening hypercapnic respiratory failure and currently requires continuous noninvasive positive-pressure ventilation (NIPPV) to maintain normal mentation and oxygenation. The patient communicates effectively using an eye-tracking augmentative device. While being examined by the medical team, he explicitly states, 'I cannot live like this anymore. Please turn off the machine and give me something for the breathlessness.' His wife is present, becomes highly distressed, and tells the physician, 'You cannot do this! The infection is clouding his mind. You must get a judge to rule on his legal competence before you let him make a decision to die.' The physician subsequently performs a thorough evaluation of the patient. The patient correctly states his diagnosis, understands the life-sustaining purpose of the NIPPV, and clearly articulates that stopping the machine will lead to his death. He consistently expresses a rational desire to avoid further prolongation of his dying process. He displays no signs of delirium, and a recent arterial blood gas analysis confirms the resolution of his prior hypercapnia. Which of the following is the most appropriate next step in management?

An occupational health department initiates a $5$-year prospective cohort study on January 1 to determine the incidence rate of a newly recognized interstitial lung disease among factory employees exposed to a specific chemical aerosol. Initially, $1,000$ healthy, disease-free employees are enrolled.

Participant follow-up data is recorded at the end of each year. The events are as follows:
- End of Year 1: $100$ employees relocate and are lost to follow-up.
- End of Year 2: $150$ employees transition to a different industry and are censored from the study.
- End of Year 3: $50$ employees are diagnosed with the interstitial lung disease.
- End of Year 4: $50$ employees are diagnosed with the interstitial lung disease.
- End of Year 5: The study concludes. All remaining employees complete the full $5$-year follow-up without developing the disease.

Assuming that individuals diagnosed with the disease are no longer considered at risk and do not contribute further person-time, what is the incidence rate of the interstitial lung disease in this cohort, expressed per $1,000$ person-years?

Following a three-day hospitalization for newly diagnosed atrial fibrillation, a 72-year-old female is cleared for discharge with a new prescription for dabigatran. The hospital's standard discharge process mandates only that the floor nurse provide verbal medication education; it does not require a formal pharmacist consultation for high-risk anticoagulants. The discharging resident enters the prescription correctly, and the nurse provides the standard verbal instructions. However, the patient misinterprets the guidance and takes the dabigatran twice as frequently as prescribed. One week later, she presents to the emergency department with a severe intraparenchymal hemorrhage. An incident investigation identifies the lack of a mandatory pharmacist counseling requirement for novel oral anticoagulants as a critical vulnerability. Which of the following terms best classifies the hospital's discharge education policy in this context?

A multidisciplinary patient safety committee is reviewing a sentinel event where a patient erroneously received an intravenous medication via an epidural route. During the root cause analysis, the team maps out the sequence of events and brainstorms corrective actions. Match each identified contributing factor or proposed intervention to its correct classification in the error taxonomy and hierarchy of safety controls.

A 32-year-old man comes to a public health clinic for a sexually transmitted infection screening. The physician considers using a newly implemented point-of-care serologic assay for *Treponema pallidum*. To evaluate the reliability of a positive result, the physician reviews a recent local validation study involving 500 high-risk patients.

In this study, 150 patients tested positive using the new point-of-care assay. Subsequent gold-standard confirmatory testing revealed that 135 of these 150 patients were truly infected. The remaining 350 patients tested negative with the new assay, and 315 of them were confirmed to be truly free of the disease by the gold standard.

Based on these study data, what is the positive predictive value (in percentage) of the new point-of-care assay?

A 68-year-old man is evaluated in the preoperative clinic prior to an elective open inguinal hernia repair scheduled for the following day. He has a history of type 2 diabetes mellitus and essential hypertension. His current medications include metformin and lisinopril. Vital signs today are temperature $37.0^\circ\text{C}$ ($98.6^\circ\text{F}$), blood pressure $132/82\text{ mm Hg}$, pulse 76/min, and respiratory rate 14/min. Physical examination is notable for a reducible right inguinal hernia. Recent laboratory studies show a hemoglobin A1c of $7.2\%$. The surgical team reviews the hospital's infection control protocols to minimize the risk of a hospital-acquired surgical site infection (SSI). Which of the following interventions is most appropriate to include in this patient's perioperative management?

An 82-year-old woman with a history of moderate Alzheimer dementia is admitted with acute hypoxic respiratory failure secondary to severe aspiration pneumonia. She is intermittently agitated, repeatedly removes her high-flow nasal cannula, and verbally refuses endotracheal intubation. The patient's adult daughter is present at the bedside, but there is no advance directive or designated healthcare proxy on file. Arrange the following steps in the most appropriate clinical and ethical sequence for navigating this patient's medical decision-making process.

A 9-year-old boy is evaluated in a busy ambulatory pediatric clinic for a suspected radius fracture after a fall. The patient's electronic health record contains a highly visible alert for anaphylaxis to nonsteroidal anti-inflammatory drugs. While preparing for radiographic imaging, the attending physician verbally instructs the clinical assistant to administer weight-based liquid acetaminophen for pain control. However, the assistant inadvertently retrieves and administers liquid ibuprofen from the multi-dose medication cabinet. Shortly after ingestion, the patient develops diffuse urticaria, periorbital edema, and wheezing. He is rapidly and successfully treated with intramuscular epinephrine and transferred to the local emergency department for observation. The clinic's safety committee is notified of the adverse event. Which of the following is the most appropriate next step in the institutional response to this incident?

Match each clinical scenario with the most appropriate ethical standard or legal doctrine guiding the medical decision-making process.

An attending physician in the intensive care unit is leading a seminar for resident physicians on the ethical and legal frameworks governing end-of-life care. The discussion focuses on how medical decisions must be made when treating adult patients facing terminal conditions, particularly as they transition from being fully alert to losing decisional capacity. The attending emphasizes that US medical jurisprudence and bioethics utilize a strict hierarchy to guide who makes decisions and what standards they must use.

Arrange the following standards of medical decision-making in their correct ethical and legal hierarchical order of priority, from the HIGHEST standard of autonomy (first to be applied) to the LOWEST standard of autonomy (last resort).