Managing Systemic Diseases Flashcards

A patient with uncontrolled Type 2 diabetes (HbA1c of 10.2%) presents for an elective oral surgery requiring IV sedation. Which of the following best describes the anesthetic concern specific to this patient's glycemic status?

Answer: Autonomic neuropathy associated with chronic uncontrolled diabetes may blunt cardiovascular responses to vasovagal episodes and hypotension during sedation

Autonomic neuropathy is a serious complication of long-standing uncontrolled diabetes. It can impair the patient's ability to compensate for hypotension, vasovagal events, or bradycardia during sedation — all of which require intact autonomic reflexes. The DAANCE candidate must recognize that the cardiovascular response to sedation-induced hypotension may be blunted, increasing the risk of prolonged or dangerous hypotension. While hyperglycemia does impair healing and immunity, and hypoglycemia is a concern, the autonomic neuropathy effect on hemodynamic stability during sedation is the most clinically specific and advanced concern.

A patient with hypertrophic obstructive cardiomyopathy (HOCM) requires moderate sedation for a lengthy extraction. Which pharmacologic approach would be MOST dangerous in this patient?

Answer: Administering a vasodilating agent such as nitroglycerin to treat a hypertensive episode

In HOCM, the left ventricular outflow tract obstruction worsens when preload or afterload decreases, or when heart rate and contractility increase. Vasodilators like nitroglycerin reduce preload dramatically, which decreases ventricular filling and worsens the dynamic obstruction — potentially causing acute decompensation or syncope. This is the opposite of what is needed. Maintaining adequate preload and avoiding tachycardia are the cornerstones of anesthetic management in HOCM. Ketamine is cautiously used but may increase sympathetic tone; opioids and benzodiazepines help avoid tachycardia and are generally safer adjuncts.

During IV sedation, a patient with known Addison's disease develops persistent hypotension unresponsive to IV fluid boluses and vasopressors. The most appropriate next step is:

Answer: Administer IV hydrocortisone 100 mg immediately and contact emergency medical services

A patient with Addison's disease (primary adrenal insufficiency) is at risk for addisonian crisis (acute adrenal crisis) during physiologic stress such as surgery or sedation, especially if they have not received adequate steroid supplementation (stress dosing). The hallmark is refractory hypotension that does not respond to fluids or vasopressors. IV hydrocortisone 100 mg is the treatment of choice because it provides both glucocorticoid and mineralocorticoid activity. EMS should be activated simultaneously. Dexamethasone has no mineralocorticoid activity and is an incorrect choice in this setting. Observation alone is inappropriate given the life-threatening nature of the crisis.

A patient with severe COPD (FEV1/FVC ratio of 0.52) is scheduled for IV sedation. Which of the following represents the most nuanced and accurate concern regarding opioid use in this patient?

Answer: Opioids should be used cautiously and titrated carefully, as they blunt the hypercapnic ventilatory drive that COPD patients may rely on, and CNS depression is disproportionately prolonged due to impaired drug clearance

Patients with severe COPD may have chronic CO2 retention, causing their primary respiratory drive to shift toward hypoxic drive (driven by low PaO2 rather than high PaCO2). Opioids blunt this hypoxic drive and further suppress ventilation. In addition, COPD patients may have impaired hepatic or renal function and reduced muscle reserve, leading to disproportionately prolonged drug effects. This does NOT mean opioids are absolutely contraindicated — careful titration with close monitoring is appropriate. Meperidine is actually disfavored due to its metabolite normeperidine causing CNS excitation and seizures, and it has no relevant bronchodilatory role. High-flow O2 masking hypercapnia without respiratory monitoring is dangerous.

A patient with end-stage renal disease (ESRD) on hemodialysis is sedated for a dental procedure. The team plans to use midazolam. Which pharmacokinetic principle is MOST clinically relevant to dosing decisions in this patient?

Answer: ESRD causes decreased serum albumin, reducing protein binding of midazolam and increasing the free (active) drug fraction, so standard doses produce exaggerated and prolonged sedation

While midazolam is primarily hepatically metabolized, ESRD affects its pharmacodynamics in a critical way: uremia causes decreased albumin (hypoalbuminemia) and displacement of drugs from protein-binding sites by uremic toxins. Since midazolam is highly protein-bound (~97%), even modest reductions in binding result in significantly higher free drug concentrations, producing deeper and more prolonged sedation than expected from a standard dose. Additionally, the active 1-OH midazolam metabolite is renally cleared and accumulates in ESRD. Hemodialysis does NOT efficiently clear midazolam due to its high protein binding and lipophilicity. Dose reduction and careful titration are essential.

A patient with a history of malignant hyperthermia (MH) susceptibility requires sedation for a complex extraction under a dentist's supervision. Which combination of agents is SAFE to use in this patient?

Answer: Propofol IV sedation with nitrous oxide/oxygen analgesia and fentanyl for pain control

Malignant hyperthermia is triggered by volatile (halogenated) inhalational anesthetics (halothane, sevoflurane, desflurane, isoflurane) and succinylcholine (a depolarizing neuromuscular blocker). All agents in options A, C, and D include at least one known MH trigger. Propofol is a non-triggering total IV anesthetic, nitrous oxide is a non-triggering inhalational agent, and fentanyl is a safe opioid — making option B the only fully MH-safe combination. The DAANCE candidate must be able to identify trigger vs. non-trigger agents precisely, as this distinction is literally life-or-death in MH-susceptible patients.