Treatment of Symptomatic Hypotension

Initial Assessment and Cause-Directed Approach

The American College of Cardiology recommends determining the underlying physiological cause of hypotension, such as vasodilation, hypovolemia, bradycardia, or low cardiac output, to guide treatment 1
For hypovolemia, the European Society of Intensive Care Medicine suggests performing a passive leg raise test to determine fluid responsiveness, with a positive likelihood ratio of 11 and pooled specificity of 92% 1
The treatment of hypovolemia involves intravascular fluid administration using crystalloid, colloid, or blood products, with an initial fluid bolus of 10-20 mL/kg in children and 250-500 mL in adults 1
For vasodilation, the Society of Critical Care Medicine recommends norepinephrine as the first-line vasopressor, with the addition of vasopressin if hypotension persists 2
Phenylephrine is best reserved for hypotension with tachycardia, as it causes reflex bradycardia, and should otherwise be reserved for salvage therapy in septic shock 1, 2
For bradycardia, the American Heart Association recommends treating with anticholinergics, such as atropine or glycopyrronium, as first-line therapy 1
For low cardiac output, the European Society of Cardiology recommends treating with positive inotropes, such as dobutamine or epinephrine, with the addition of norepinephrine if hypotension persists 1, 2

For orthostatic hypotension, the American Autonomic Society recommends non-pharmacological measures as the first therapeutic approach, including excluding exacerbating drugs, educating patients on behavioral strategies, and increasing fluid and salt intake 3, 4
Midodrine is the first-line drug for orthostatic hypotension, with a Class I recommendation and Level A evidence, and should be dosed individually up to 10 mg two to four times daily 3, 4
Fludrocortisone is another first-choice drug for orthostatic hypotension, with a Class IIa recommendation and Level B evidence, and should be dosed initially at 0.05-0.1 mg daily, titrated to 0.1-0.3 mg daily 3
In trauma patients without brain injury, the Eastern Association for the Surgery of Trauma recommends restricted volume replacement, targeting a systolic blood pressure of 80-90 mmHg until major bleeding is controlled 1
In severe traumatic brain injury, the Brain Trauma Foundation recommends maintaining a mean arterial pressure of at least 80 mmHg to ensure adequate cerebral perfusion 1
For septic shock, the Society of Critical Care Medicine recommends norepinephrine as the initial vasoactive drug, with the addition of dobutamine or epinephrine if hypotension persists 2

The American Society of Anesthesiologists recommends administering vasoactive agents targeted to effect, rather than based on fixed doses, and using intra-arterial monitoring for precise blood pressure targeting 2
Continuous intraoperative arterial pressure monitoring reduces the severity and duration of hypotension compared to intermittent monitoring 1
Serial monitoring of serum electrolytes and renal function is mandatory when using fludrocortisone 3

The American College of Emergency Physicians recommends avoiding reflexive fluid administration without assessing fluid responsiveness, as approximately 50% of hypotensive patients are not hypovolemic 1
Permissive hypotension should not be used in traumatic brain injury, and mean arterial pressure should be maintained at least 80 mmHg 1
Aggressive fluid resuscitation should be avoided in trauma patients without brain injury, as it increases mortality 1
Additional fluid boluses should be avoided in patients with cardiac dysfunction or volume overload signs, such as pulmonary edema 1
The goal of increasing standing blood pressure should be balanced against avoiding marked supine hypertension when treating orthostatic hypotension 3, 4
Doses of orthostatic hypotension medications should not be increased if symptomatic hypotension occurs 5