Vasovagal Syncope: This is a common cause of fainting, especially in older adults, often triggered by stress, pain, or prolonged standing. The brief duration of the faint (5 minutes) and the patient's age make this a plausible diagnosis.

Orthostatic Hypotension: A drop in blood pressure upon standing can cause fainting, especially in elderly patients who may have decreased blood volume, medications that lower blood pressure, or autonomic nervous system dysfunction.
Cardiac Arrhythmias: Conditions like atrial fibrillation or other heart rhythm disturbances can lead to fainting by reducing cardiac output.
Hypoglycemia: Low blood sugar can cause fainting, particularly in diabetic patients or those taking certain medications.

Myocardial Infarction (MI) or Pulmonary Embolism (PE): Although less common causes of fainting, these conditions are life-threatening and must be considered, especially if the patient has risk factors such as a history of heart disease or recent immobilization.
Stroke or Transient Ischemic Attack (TIA): While less typical presentations of stroke or TIA, fainting can occasionally be associated with these conditions, particularly if accompanied by other neurological symptoms.
Aortic Dissection: A tear in the aorta's inner layer can lead to fainting among other symptoms and is a medical emergency.

Subclavian Steal Syndrome: A rare condition where there's a reversal of blood flow in the subclavian artery, potentially leading to fainting due to decreased blood flow to the brain.
Pheochromocytoma: A rare tumor of the adrenal gland that can cause episodes of high blood pressure, leading to fainting.
Micturition Syncope: Fainting that occurs during or after urination, more common in older men but can occur in women, especially if there's a history of prostate issues or urinary retention.