Differential Diagnosis

The patient's symptoms of sudden onset of hot flashes, sweating, weakness, and subsequent sleepiness, followed by feeling cold, are concerning and warrant a thorough evaluation. Based on the provided information, the differential diagnosis can be categorized as follows:

• Single Most Likely Diagnosis
  • Vasovagal Syncope: This condition is characterized by a sudden drop in blood pressure, heart rate, and blood flow to the brain, leading to symptoms like sweating, weakness, and fainting. The patient's history of atrial fibrillation and the fact that the episodes occurred after physical activity (traveling from Yorkton and after work) support this diagnosis. The patient's blood pressure and heart rate after the event are within normal limits, which is consistent with vasovagal syncope.
• Other Likely Diagnoses
  • Dehydration: Although the patient consumed multiple glasses of water during the episodes, dehydration could still be a contributing factor, especially if the patient was not adequately hydrated before the events.
  • Anxiety or Panic Attack: The patient's symptoms of sweating, hot flashes, and weakness could be indicative of an anxiety or panic attack, especially if the patient has a history of anxiety disorders.
  • Hypoglycemia: Low blood sugar could cause symptoms like sweating, weakness, and confusion, although the patient did not report any symptoms of hunger or tremors.
• Do Not Miss Diagnoses
  • Cardiac Arrhythmia: Given the patient's history of atrial fibrillation, it is essential to rule out other cardiac arrhythmias that could be causing the symptoms, such as ventricular tachycardia or bradycardia.
  • Myocardial Infarction or Cardiac Ischemia: Although the patient's electrocardiogram (ECG) and troponin levels are not provided, it is crucial to consider the possibility of a myocardial infarction or cardiac ischemia, especially in a patient with a history of atrial fibrillation.
  • Stroke or Transient Ischemic Attack (TIA): The patient's sudden onset of symptoms, including weakness and confusion, could be indicative of a stroke or TIA.
• Rare Diagnoses
  • Pheochromocytoma: This rare tumor of the adrenal gland could cause episodes of hypertension, sweating, and palpitations, although it is unlikely given the patient's normal blood pressure after the event.
  • Autonomic Dysfunction: Certain conditions like autonomic dysfunction or dysautonomia could cause symptoms like orthostatic hypotension, sweating, and weakness, although these conditions are relatively rare.

Next steps would include:

• Electrocardiogram (ECG) to evaluate for cardiac arrhythmias
• Blood tests to rule out hypoglycemia, dehydration, and cardiac enzymes
• Holter monitor or event monitor to capture any cardiac arrhythmias
• Consider a tilt table test to evaluate for vasovagal syncope
• Referral to a cardiologist to evaluate the patient's atrial fibrillation and to rule out other cardiac conditions.