Trial MCQ Paper 1

Correct Answer: D) Refer him for a stress ECG and echocardiography

Central chest pain described as heaviness, dull, and aching, especially if it radiates to the jaw, left arm, or epigastrium, is likely ischemic in origin.

This patient's pain characteristics (duration less than 20 minutes, predictable with exertion, and relieved by rest or nitrates) suggest stable angina. Stable angina occurs when increased heart oxygen demand due to activity leads to ischemia, as the stenotic coronary arteries cannot meet the demand.

In contrast, unstable angina involves new or changed ischemic pain patterns (duration, intensity, frequency, or exertion level).

Given this patient's stable presentation, the next best step is performing a stress test to assess coronary artery stenosis if the ECG or diagnosis is unclear.

• Option A: Reassuring and discharging the patient is not appropriate until a full assessment is complete.
• Option B: Echocardiography could be useful but is not the most urgent step.
• Option C: Admission to CCU and cardiac enzyme monitoring are indicated for unstable presentations, not in stable angina.
• Option E: Gastroenterology referral is not appropriate as the pain is typical for cardiac ischemia.

Correct Answer: D) Streptokinase

There is a high prevalence of IgG antistreptokinase antibodies among Aboriginal Australian patients, making streptokinase an inappropriate choice for thrombolytic therapy in acute ST elevation myocardial infarction in this group. The presence of these antibodies renders treatment with streptokinase ineffective.

Correct Answer: A) Jugular venous pressure

The prognosis of systolic heart failure can be predicted by jugular venous pressure (JVP) and the presence of a third heart sound (S3). An increased JVP or the presence of an S3 sound indicates a poorer prognosis. The other options are useful for diagnosis but do not have predictive value for prognosis.

Correct Answer: B) Prolactinoma

The patient's symptoms, along with a significantly elevated prolactin level, suggest hyperprolactinemia. While medications such as risperidone can cause hyperprolactinemia, the prolactin levels associated with drug-induced hyperprolactinemia are usually below 5000 mU/L. A prolactin level above 5000 mU/L is more indicative of a prolactinoma.

Correct Answer: A) Intravenous calcium

Patients with symptomatic hypocalcemia, such as paresthesia of the hands, feet, and perioral area (sensory equivalents of tetany), and any calcium level below the reference range, or those with asymptomatic hypocalcemia with total calcium levels acutely below 1.9 mmol/L, require urgent intravenous calcium replacement. The recommended treatment is 10 to 20 ml of 10% calcium gluconate in 50-100 ml of Dextrose 5%, administered intravenously over 10-20 minutes with ECG monitoring. This can be repeated until the patient becomes asymptomatic and should be followed by a calcium gluconate infusion. Calcium chloride is an alternative but is more irritating to veins and should only be given via a central line.

For asymptomatic hypocalcemia (with calcium levels above 1.9 mmol/L) or latent tetany (evidenced by a positive Trousseau and/or Chvostek sign), oral calcium with or without vitamin D supplementation would be the appropriate choice.

Correct Answer: B) Laryngomalacia

Explanation:
The clinical history is suggestive of laryngomalacia, a congenital softening of the tissues of the larynx above the vocal cords. Laryngomalacia is the most common cause of noisy breathing in infancy. In this condition, the laryngeal structure is malformed and floppy, causing the tissues to fall over the airway opening and partially block it.

Symptoms of laryngomalacia usually appear at birth and often become more pronounced within the first few weeks of life. Most children outgrow laryngomalacia by 18 to 20 months of age. Key symptoms include:

• Noisy breathing – an audible wheeze when a baby inhales, often worse when the baby is agitated, feeding, crying, or sleeping on their back.

• High-pitched sound on inspiration.

• In severe cases: difficulty feeding, poor weight gain, and choking while feeding.

• (Option A) Acute asthma makes breathing difficult, with a wheeze audible in any position. Asthma is an extremely rare diagnosis in a 2-week-old neonate.

• (Option C) Croup (laryngotracheobronchitis) is most commonly caused by para-influenza virus type 1 infection and is characterized by a distinctive seal-like barking cough and inspiratory stridor. Croup primarily affects children aged 6 months to 3 years. This neonate is not in respiratory distress, is otherwise healthy, and has no cough.

• (Option D) Acute bronchiolitis is an acute viral infection of the lower respiratory tract, typically affecting infants younger than 12 months of age. It is characterized by respiratory distress, wheezing, and inspiratory fine crackles, primarily caused by the respiratory syncytial virus (RSV). Treatment is supportive with oxygen and hydration.

• (Option E) Epiglottitis is a rapidly progressive bacterial infection of the epiglottis and surrounding tissues, leading to sudden respiratory obstruction and death if untreated. Symptoms include a severe sore throat, dysphagia, high fever, drooling, and inspiratory stridor. This child does not present with these symptoms.

NOTE: While expiratory stridor suggests an obstruction in the lower trachea, inspiratory stridor points to an obstruction above the glottis.

Correct Answer: E) Dissociative fugue

Explanation:

The presence of a gap in memory, during which the person has often traveled or engaged in actions they cannot recall, strongly suggests a diagnosis of dissociative fugue. This diagnosis is further supported by the presence of an emotional stressor, in this case, being fired from work.

• Option A - Automatism: Automatism refers to brief unconscious behaviors typically lasting seconds to minutes, sometimes longer, but does not involve prolonged memory loss or unplanned travel.

• Option B - Major Depression: Major depression presents with low mood, lack of energy, poor concentration, and changes in appetite or sleep patterns for at least two weeks, which is not the case here.

• Option C - Depersonalization: The key finding in depersonalization is an out-of-body experience, where a person feels detached from themselves. This is not observed in this scenario.

• Option D - Derealization: Derealization involves a distorted perception of the environment, often with sensations like jamais vu (finding something familiar strangely unfamiliar) or déjà vu, which is not indicated here.

Correct Answer: C) Admit her.

Explanation:
Based on the concept of autonomy, every individual has the right to make decisions about their own body as long as they are competent. When a patient is unable to make decisions, previously documented instructions, such as a valid living will or advance directives, guide the treating team regarding their care.

In this case, the patient’s living will specifies that she does not wish to be admitted if she is terminally ill. However, neither a femoral neck fracture nor the reversible drowsiness caused by opiates meets the definition of a terminal illness. Therefore, she should be admitted to treat the effects of the morphine (opiates) and reverse her current condition.

Once her condition is stabilized, further management, including surgical fixation of the fracture or other treatment options, can be discussed with her.

Key Points:

• A living will applies only to the specific conditions outlined in it. Here, the condition does not align with the definition of terminal illness.
• Admission and treatment are necessary to address the current, reversible state caused by the opiate overdose.
• Once stabilized, the patient can participate in further decision-making about her treatment.

Correct Answer: E) Take him to a safe place and let him smoke under supervision.

Explanation:
In a mental health setting, cigarettes are sometimes used as a patient management tool by staff to mediate exchanges and build relationships between staff and patients. This can include encouraging compliance with treatments or other requests.

While there is debate over the implementation of non-smoking policies in psychiatric wards, in emergency situations involving severely agitated and disturbed patients, allowing the patient to smoke can help de-escalate the situation without resorting to coercive treatments.

In Australia, a common practice in such situations is to allow the patient to smoke under appropriate supervision, ensuring minimal or no exposure of others to cigarette smoke.

Why other options are less appropriate:

• Option A: Discharging an uncooperative and agitated patient is inconsistent with the duty of care and can place the patient and others at significant risk.
• Option B: Contacting immigration authorities while the patient is in need of medical and psychiatric care is not appropriate. Medical care should take precedence, and legal matters can follow once the patient is stabilized.
• Option C: Offering nicotine gum or patches may help patients attempting to quit smoking, but in this case, it is unlikely to satisfy the agitated patient.
• Option D: Calling the police while the patient is still in need of medical care is premature. Police involvement, if necessary, can occur after the patient receives adequate medical attention.

Allowing the patient to smoke under supervision is the most practical approach to calm the patient while ensuring safety for all involved.

Correct Answer: A) Take consent from the Mental Health Tribunal.

Explanation:
ECT is a widely used treatment, particularly for major depression with psychotic features as seen in this patient. Regulations governing ECT administration and consent vary by jurisdiction. For involuntary patients, specific legal authorization is required before proceeding with ECT unless it is an emergency.

In non-emergency situations, approval must be obtained from the Mental Health Tribunal, Guardianship Board, or a similar authority. This process ensures that:

• The patient lacks the capacity to give informed consent.
• At least two medical practitioners (one being a psychiatrist) agree that ECT is a reasonable and necessary treatment to prevent serious mental or physical deterioration.

Why other options are less appropriate:

• Option B: Giving ECT without consent under the duty of care is only permissible in life-threatening emergencies where immediate treatment is required to save the patient’s life or prevent irreparable harm. Since this patient is clinically stable, the approval process should be followed.
• Option C and E: Unlike other medical procedures, ECT requires approval from a legal authority, not from relatives or hospital administrators.
• Option D: While nasogastric feeding and antidepressants might address immediate nutritional and medication needs, they do not replace ECT, which is the indicated treatment for her condition.

Key Points:

• Emergency ECT without tribunal approval should only be performed when delay poses a risk of serious harm.
• The Mental Health Tribunal or equivalent must authorize non-emergency ECT for involuntary patients.
• In cases like this, where the patient is not in immediate danger, following the formal process ensures ethical and legal compliance.

ECT should only be administered in an approved hospital setting with a minimum of two medical practitioners present—one experienced in ECT administration and the other in anesthesia.

Correct Answer: C) Organize a full course of hepatitis B immunization

Explanation:
If the index case is HBsAg negative and unlikely to be in the window period, no post-exposure prophylaxis is required for the nurse if she has been immunized. Since the nurse is unsure of her immunization status, she should receive a full course of hepatitis B vaccination, ideally started within 24 hours of exposure.

Another appropriate approach (not listed as an option) would be to check the nurse's HBV antibody titer. If the titer is ≥10 mIU/ml, no vaccination is required.

Option A: Although the nurse is not likely to become infected from this exposure, follow-up for immunization is needed due to uncertain immunization status.

Option B: Since the patient is HBsAg negative and unlikely to be in the window period, post-exposure prophylaxis (such as hepatitis B immunoglobulin) is not required.

Option D: While the incident should be reported to a team manager or supervisor, reporting to an infectious disease specialist is not necessary in this situation.

Option E: Checking the nurse’s HBsAg status would be necessary if the index case were HBsAg positive, but it is not required in this case because the patient is HBsAg negative.

Correct Answer: A) Vaccinate him now.

Explanation:
The pertussis-containing vaccine is critical for preventing pertussis, a disease associated with significant morbidity and occasional mortality in infants. The DTPa vaccine is typically administered as part of a 3-dose primary schedule at 2, 4, and 6 months of age, with doses starting as early as 6 weeks.

Key considerations:

• Mild illness (e.g., URTI): Vaccination can proceed in children with mild disease and fever below 38.5°C. This child’s fever of 38.2°C and mild URTI symptoms are not contraindications to vaccination.
• Previous adverse reaction: The swelling described after the previous dose is a benign and self-limiting adverse event associated with DTPa booster doses. It is not a contraindication to further vaccination.
• Contraindications to DTPa: Absolute contraindications include anaphylaxis to a previous dose of DTPa or any vaccine component. This child does not meet these criteria.

Option B: Delaying vaccination due to mild URTI is unnecessary and could leave the child at risk for pertussis.

Option C: Omitting the pertussis component would leave the child unprotected against a potentially severe infection.

Option D: dTpa contains lower doses of diphtheria and pertussis antigens, designed for adolescents and adults, and is not appropriate for infants.

Option E: Delaying vaccination by 2 months unnecessarily extends the period of vulnerability to pertussis and other diseases.

This infant’s mild illness and history of a benign adverse reaction do not warrant a delay in vaccination, and the third dose of DTPa should be given now.

Correct Answer: D) Cross-sectional study.

Explanation:
The primary objective of determining the state of vitamin D deficiency is to assess prevalence within the population. A cross-sectional study is the most appropriate design for such a purpose because it evaluates the condition of a population at a single point in time or over a short period.

Key Characteristics of Cross-Sectional Studies:

• Prevalence Data: They are often referred to as prevalence studies because they measure the proportion of a population affected by a particular condition at a specific point in time.
• Study Design: The study sample represents the population, and data is collected simultaneously on exposure and outcome.
• Statistical Outcomes: Cross-sectional studies provide data on prevalence, odds ratio, and risk estimations.

Why Not Other Options?

• Option A (Cohort Study): Used to determine incidence and causal relationships by following a group over time. It is time-consuming and not designed to measure prevalence.
• Option B (Case-Control Study): Compares cases with controls retrospectively to identify risk factors, but it does not measure population prevalence.
• Option C (Randomized Controlled Trial): An interventional study designed to test the efficacy of an intervention, not to determine prevalence in a population.
• Option E (Case Series): A descriptive report on clinical characteristics of a group but lacks the ability to generalize or determine prevalence.

Correct Answer: A) Serum FSH level

A 2.5 times or greater increase in serum FSH level suggests irreversible testicular failure, making FSH the most important endocrine test in the evaluation of male infertility, particularly in cases of azoospermia. Although serum testosterone is useful for diagnosing hypogonadism, its levels can vary by age and may not indicate irreversible testicular failure. Other investigations, such as LH, inhibin, anti-sperm antibodies, chromosome analysis, and testicular ultrasound, are helpful in assessing male infertility, but serum FSH is the primary hormonal test in cases of azoospermia.

Correct Answer: A) Cephalexin

The clinical manifestation is characteristic of a urinary tract infection (UTI). With the absence of fever and flank pain, infectious cystitis is more likely. During pregnancy, the following antibiotics are considered safe for the treatment of UTIs:

First-line:

• Cephalexin (Category A) 500mg orally, 6-hourly for 10 days

Second-line:

• Nitrofurantoin (Category A) 50mg orally, 6-hourly for 10 days

Third-line:

• Amoxicillin + clavulanate (Category B1) 500+125mg orally, 12-hourly for 10 days

These drugs are also used for the treatment of asymptomatic bacteriuria during pregnancy.

• (Option B) Trimethoprim is a folate antagonist and may increase the risk of neural tube defects, so it is generally avoided during pregnancy. It is first-line therapy for UTIs in non-pregnant women and adult men.
• (Option C) Tetracyclines, such as doxycycline, are contraindicated in pregnancy due to their teratogenic risk.
• (Option D) Nitrofurantoin is inferior to cephalexin for treating UTIs during pregnancy. It should be avoided near term due to the risk of neonatal hemolysis and in those with renal impairment because it is renally excreted.
• (Option E) Ciprofloxacin, a fluoroquinolone, though categorized as B1 and generally safe in pregnancy, should not be used as a first-line agent as it is reserved for treating Pseudomonas aeruginosa and resistant infections.

Correct Answer: A) Progressive hepatic cirrhosis

The following are major complications associated with iron overload:

Cardiac problems:

• Congestive heart failure, dysrhythmias, and pericarditis

Endocrine problems:

• Delay in growth and sexual development, hypoparathyroidism, hypothyroidism, and diabetes mellitus

Hepatic problems:

• Progressive hepatic fibrosis and cirrhosis

Of the given options, only progressive hepatic cirrhosis could be a complication of iron overload.

• (Option B) Extramedullary hematopoiesis is a feature of thalassemia, not a complication of iron overload.
• (Option C) Shortness of breath may occur if iron overload has already led to heart failure but is not a direct effect of iron overload.
• (Option D) Hemolysis and anemia are part of the disease mechanism of thalassemia, not an adverse effect of iron overload.
• (Option E) Autosplenectomy is a feature of sickle cell disease and occurs due to splenic infarcts.

Correct Answer: B) Von Willebrand disease.

The scenario describes a healthy child with a platelet type of bleeding. In bleeding disorders with faulty platelet or platelet-mediated coagulation, bleeding tends to occur immediately after insult and is superficial. In patients with factor deficiency (factor-type bleeding), the bleeding is deep (e.g., into muscles and joints) and delayed, as platelets initially establish hemostasis.

Von Willebrand disease (VWD) is an inherited disorder with many types (22 types) and clinical pictures. Almost all types cause mild bleeding problems with an excellent prognosis. The most common types often have an autosomal dominant inheritance. This disease is very common (1 in 100 population) and is the most common inherited bleeding disorder.

Von Willebrand factor is a circulating factor that is attached to factor VIII. This factor plays an essential role in coagulation by gluing platelets together and to the vascular lining. Because the clinical disease can be very mild, most cases remain undiagnosed. However, symptomatic cases can include:

• Easy bruising
• Mucosal bleeding (e.g., epistaxis, menorrhagia, gastrointestinal bleeding, etc.)
• No history of hemarthroses or intramuscular hematomas (except for type 3, which is very rare but can have musculoskeletal manifestations)
• Prolonged bleeding after trauma or surgery

The clinical picture and a normal platelet count suggest VWD as the most likely diagnosis.

• (Option A) Immune thrombocytopenic purpura (ITP), as the name implies, should have low platelet count, which is not present in this patient.
• (Option C) Hemophilia presents with factor-type bleeding (deep and delayed).
• (Option D) With isolated thrombocytopenia and an otherwise healthy child, leukemia is very unlikely, if possible at all.
• (Option E) Factor V Leiden mutation presents with hypercoagulability, not bleeding disorders.

Correct Answer: C) Pyogenic granuloma.

The fleshy red lesion on the distal interphalangeal joint of this patient is consistent with the diagnosis of pyogenic granuloma (PG). PG is a common benign acquired vascular neoplasm of the skin and mucous membrane. Its etiology is unknown, but some theories suggest it may result from minor trauma, especially in PGs of the fingers. "Pyogenic granuloma" is a misnomer, as the lesion is neither pyogenic nor a true granuloma.

It appears as an erythematous (fleshy red), dome-shaped papule or nodule that bleeds easily and is prone to ulceration, erosion, and crusting. Pyogenic granulomas are most often seen in adolescents and young adults, and up to 5% of pregnant women may experience them. Although very rare, PGs have also been reported in locations such as the gastrointestinal tract, larynx, nasal mucosa, conjunctiva, and cornea.

• (Options A, D, and E) Abscess, epidermoid cyst, and mucous cyst are usually covered with skin.
• (Option B) Pyoderma gangrenosum typically presents with a well-defined border that is usually violet or blue.

Correct Answer: C) Common peroneal nerve.

The symptoms described—foot drop, weakness of ankle dorsiflexion, and sensory loss over the outer aspect of the leg—suggest an injury to the common peroneal nerve, which can be vulnerable during knee surgeries. This nerve is responsible for dorsiflexion (raising the foot upwards) and eversion (turning the sole of the foot outward) through its branches: the deep peroneal nerve (which innervates the dorsiflexors) and the superficial peroneal nerve (which is involved in sensation over the outer aspect of the leg).

The common peroneal nerve wraps around the fibular head, making it particularly susceptible to injury or compression during surgical procedures involving the knee.

• Option A: L4 nerve root involvement can lead to weakened knee reflex and partially impaired ankle inversion, but it does not account for the foot drop or sensory loss over the outer aspect of the leg.

• Option B: L5 nerve root damage can mimic some features of a common peroneal nerve injury, particularly with foot drop. However, the context of recent knee surgery makes direct injury to the common peroneal nerve more probable.

• Option D: Tibial nerve injury would affect plantar flexion (pointing the toes downward), result in loss of sensation on the sole of the foot, and impair the ankle jerk, which is intact in this case.

• Option E: Sciatic nerve damage would involve a more extensive range of deficits, affecting both the common peroneal and tibial nerve functions, resulting in global impairment of foot and ankle movements.

Therefore, the presentation aligns most closely with an injury to the common peroneal nerve, especially given the recent knee surgery.

Correct Answer: B) Injury to the brachial plexus.

The symptoms of diminished shoulder abduction and sensory loss over the deltoid area suggest involvement of the C5 and C6 nerve roots. Additionally, decreased elbow extension, which involves the radial nerve (C5, C6, C7, C8, and T1), indicates a broader issue potentially affecting multiple nerve roots. This makes an injury to the brachial plexus the most likely cause of the patient's symptoms, as the brachial plexus involves multiple nerve roots (C5-T1) that contribute to the innervation of the shoulder and upper limb.

• Option A: C5 nerve palsy could explain the loss of sensation over the deltoid area and weakened shoulder abduction, but it does not account for impaired elbow extension, which involves multiple nerve roots.

• Option C: Carpal tunnel syndrome affects the median nerve due to compression at the wrist and does not involve elbow extension, shoulder abduction, or sensory loss over the deltoid area.

• Options D and E (C7 or C6-C7 nerve root injuries) could justify weakened elbow extension but do not explain the issues with shoulder abduction or the sensory deficit in the deltoid area, which are associated with the axillary nerve (C5, C6).

Therefore, a brachial plexus injury is the most comprehensive explanation for the range of symptoms presented.

Correct Answer: A) Labyrinthitis.

Among the options, labyrinthitis, Meniere’s disease, and lateral medullary syndrome can cause acute onset vertigo, tinnitus, and hearing loss. Ataxia can also present in patients with cerebellar or vestibular disorders. Given the inconclusive neurological examination, labyrinthitis is the most likely diagnosis.

Acute labyrinthitis often presents with sudden onset vertigo, accompanied by nausea, vomiting, tinnitus, and hearing loss. In about 50% of cases, there is a history of a preceding viral upper respiratory infection. Vertigo is typically triggered by changes in head position, with episodes lasting from a few seconds to several minutes.

Correct Answer: C) Periductal mastitis

Of the given options, periductal mastitis is found to be caused by vitamin A deficiency. Periductal mastitis, also known as subareolar abscess, squamous metaplasia of lactiferous ducts, or Zuska disease, is an inflammatory condition of the subareolar ducts. Periductal mastitis primarily affects young women but can occur in men as well. Periductal mastitis is a separate entity from duct ectasia, which usually affects older women and is characterized by dilated ducts and sticky, toothpaste-like discharge. The cause of periductal mastitis is unknown. However, vitamin A deficiency and smoking have been implicated as potential causes.

Correct Answer: B) Dextrose 10% intravenously

In children with type 1 diabetes mellitus, hypoglycemia is the most common complication encountered. Hypoglycemia may lead to seizures and loss of consciousness. In childhood (other than the neonatal period), hypoglycemia is defined as a blood glucose level of <2.6 mmol/L. The most appropriate treatment for severe hypoglycemia when the patient is unconscious and unable to take oral glucose is with a bolus of intravenous dextrose 10%, 2.5 to 5 mL/kg, followed by 0.03 to 0.05 mL/kg/minute until the patient is stable.

In adults with hypoglycemia, a 50% glucose solution is used for the treatment of severe hypoglycemia. This solution is not recommended for children because it can result in serum hyperosmolarity and death. In a conscious and cooperative child, the oral route is preferred.

Correct Answer: A) Alendronate

With two fractured vertebrae and a T-score of -2.8, this patient is suffering from osteoporosis. Medical treatment is indicated for the following patient groups:

• Those with a minimal trauma fracture
• Those aged 70 years or over
• Those with a T-score of -2.5 or lower
• Those currently on prolonged (at least 3 months) high-dose corticosteroid treatment (at least 7.5 mg/day prednisolone or equivalent) and with a T-score of -1.5 or lower.

There are different options for medical prevention and treatment of osteoporosis, such as bisphosphonates (e.g., alendronate, risedronate), estrogen receptor modulators (e.g., raloxifene), strontium ranelate, and teriparatide.

Supplementation of calcium and vitamin D should be considered for all patients, as studies suggest that the optimal efficacy of medical treatment, to a considerable extent, depends on the availability of these two.

Bisphosphonates are always first-line medications in postmenopausal women (even those with a personal history of breast cancer). Whenever bisphosphonates are considered for treatment, close attention should be paid to vitamin D status, and its deficiency should be corrected prior to starting treatment. Achieving a 25-hydroxy vitamin D plasma level of 50 nmol/L is the target before the patient is started on bisphosphonates.

Vitamin D supplementation is indicated for the following patient groups:

• Those with proven vitamin D deficiency
• Institutionalized or housebound people
• Women who are shrouded for cultural reasons

Since this woman does not expose herself to sunlight due to fear of developing melanoma, she should be categorized as housebound and vitamin D deficient because exposure to sunlight is the most significant source of vitamin D production in the body. She definitely needs alendronate as first-line medical treatment for her osteoporosis, but not before her vitamin D deficiency is corrected to a level of 50 nmol/L or above.

Correct Answer: E) DC cardioversion

The ECG is characteristic of supraventricular tachycardia (SVT), which presents with tachycardia, regular and monomorphic QRS complexes, and absence of P waves.

SVT is a common condition that can affect individuals of all age groups. Clinical manifestations vary from asymptomatic to severe symptoms.

Common symptoms of SVT include:

• Palpitations: >96%

• Dizziness: 75%

• Shortness of breath: 47%

• Syncope: 20%

• Chest pain: 35%

• Fatigue: 23%

• Diaphoresis: 17%

• Nausea: 13%

Rare complications of paroxysmal SVT include myocardial infarction, congestive heart failure, syncope, and sudden death.

Acute management of SVT involves controlling the rate and preventing hemodynamic collapse. Patients with hemodynamic instability (hypotension, chest pain, dyspnea, or confusion) should receive immediate cardioversion after sedation.

In this case, the patient has a systolic blood pressure of less than 90 mmHg, indicating hemodynamic instability. Therefore, DC cardioversion is the most appropriate next step.

If the patient were stable, initial management would include vagal maneuvers. If unsuccessful, adenosine can be used, followed by AV nodal blocking agents such as calcium channel blockers (diltiazem or verapamil) or beta-blockers (metoprolol).

Incorrect options:

• A) Atropine and D) Pacemaker insertion are used for symptomatic bradycardia, which is not applicable in this case.

• B) Intravenous diltiazem and C) Intravenous metoprolol are used for stable SVT, not unstable cases.