Fluctuating systemic vasomotor instability

Specialty: General.

• episodic vasomotor lability
• fluctuating vasomotor crises
• intermittent vasomotor instability

Why it occurs

• Fluctuating autonomic dysautonomia or postural orthostatic tachycardia syndrome (where the regulation of peripheral venous tone oscillates, causing alternating episodes of flushing, paleness, heat and cold sweating)
• Panic disorder with recurrent panic attacks (peaks of sympathetic and parasympathetic hyperactivity that generate drastic but self-limiting vasomotor instability)
• Menopausal transition phase of high hormonal fluctuation (where estradiol levels vary unpredictably, generating peaks of hot flashes and alternating intense chills)
• Fluctuating consumption or irregular patterns of short-acting antihypertensive or antidepressant drugs (such as venlafaxine or paroxetine, which cause intermittent withdrawal symptoms if doses are missed)
• Rapid gastric emptying syndrome or postprandial dumping (drop in blood pressure and redistribution of blood flow with vasomotor instability after meals).

Initial workup

Recording of blood pressure and heart rate in standing and recumbent positions during symptomatic peaks, 24-hour electrocardiographic Holter, dosage of fractionated metanephrines in 24-hour urine, serum FSH and estradiol, and transthoracic echocardiogram.

Standard management

• Clonidine — 0.075 mg orally every 12 hours, useful for its modulating effect on the thermoregulatory center and peripheral sympathetic discharge
• Propranolol — 10 to 20 mg orally every 8 to 12 hours to modulate hyperadrenergic peripheral manifestations such as sweating and tachycardia
• Physical support measures such as the use of elastic graduated compression stockings for the lower limbs.