In a patient with septic shock and a history of chronic hypertension, what should be the initial mean arterial pressure target and first‑line vasopressor therapy?

Vasopressor Management in Septic Shock with Chronic Hypertension

In a patient with septic shock and chronic hypertension, norepinephrine is the mandatory first-line vasopressor, and the initial MAP target should be 70–85 mmHg rather than the standard 65 mmHg to reduce the need for renal replacement therapy. 1

Initial Fluid Resuscitation

• Administer at least 30 mL/kg of crystalloid within the first 3 hours before or concurrent with vasopressor initiation 2, 1
• Continue fluid challenges as long as hemodynamic improvement occurs, using dynamic variables (pulse pressure variation, stroke volume variation) or static variables (arterial pressure, heart rate, urine output) to guide further boluses 2

First-Line Vasopressor: Norepinephrine

• Start norepinephrine immediately when hypotension persists after initial fluid resuscitation, beginning at 0.02–0.05 µg/kg/min via central venous access 1
• Norepinephrine is the only acceptable first-line agent, with a Grade 1B strong recommendation from the Surviving Sepsis Campaign 2, 1
• Place an arterial catheter for continuous blood pressure monitoring as soon as practical 2, 1

MAP Target in Chronic Hypertension

• Target MAP of 70–85 mmHg in patients with pre-existing chronic hypertension 1, 3, 4
• This higher target reduces the incidence of acute kidney injury and need for renal replacement therapy compared to the standard 65 mmHg target 1, 4
• The standard MAP target of 65 mmHg is appropriate only for patients without chronic hypertension 2, 1

Evidence Supporting Higher MAP Targets

The recommendation for higher MAP targets in chronic hypertension is based on moderate-quality evidence showing that these patients have altered renal autoregulation 3, 5. A MAP of 80–85 mmHg minimizes renal injury in this population, though it carries an increased risk of arrhythmias 3. The lower limit of renal autoregulation is shifted rightward in chronic hypertension, making the standard 65 mmHg target insufficient for adequate organ perfusion 3, 5.

Escalation for Refractory Hypotension

Add Vasopressin (Second-Line)

• Add vasopressin at a fixed dose of 0.03 units/min when norepinephrine reaches 0.1–0.25 µg/kg/min and MAP remains below target 1
• Vasopressin must always be added to norepinephrine, never used as monotherapy 2, 1
• Do not exceed 0.03–0.04 units/min except as salvage therapy; higher doses cause cardiac, digital, and splanchnic ischemia 2, 1
• Vasopressin may be particularly beneficial in this scenario because it lowers the autoregulatory threshold and preserves renal perfusion better than norepinephrine alone 5

Add Epinephrine (Third-Line)

• Add epinephrine starting at 0.05 µg/kg/min, titrating up to 0.3 µg/kg/min, when MAP cannot be achieved with norepinephrine plus vasopressin 1

Add Dobutamine (For Persistent Hypoperfusion)

• Add dobutamine 2.5–20 µg/kg/min when MAP is adequate but signs of tissue hypoperfusion persist (elevated lactate, low urine output, altered mental status), especially with evidence of myocardial dysfunction 2, 1

Agents to Avoid

Dopamine

• Dopamine is strongly contraindicated as first-line therapy with a Grade 1B recommendation 2
• Dopamine increases absolute mortality by 11% and causes significantly more arrhythmias compared to norepinephrine 1, 6
• Use dopamine only in highly selected patients with bradycardia and low arrhythmia risk 2, 1
• Low-dose dopamine for renal protection is Grade 1A contraindicated 2, 1

Phenylephrine

• Phenylephrine is not recommended except in three specific circumstances: (1) norepinephrine-induced serious arrhythmias, (2) documented high cardiac output with persistent hypotension, or (3) salvage therapy when all other agents have failed 2, 1
• Phenylephrine can compromise microcirculatory flow and tissue perfusion despite raising MAP 1

Monitoring Beyond MAP

• Measure serum lactate at baseline and repeat within 6 hours if elevated; aim for lactate clearance as a resuscitation endpoint 1
• Maintain urine output ≥0.5 mL/kg/h as an indicator of adequate renal perfusion 1
• Assess mental status, capillary refill, and skin perfusion every 2–4 hours 1
• In patients with chronic hypertension, monitor closely for arrhythmias when targeting higher MAP values 3

Common Pitfalls to Avoid

• Do not delay norepinephrine initiation while pursuing aggressive fluid resuscitation if life-threatening hypotension is present 1, 7
• Do not use the standard 65 mmHg MAP target in patients with chronic hypertension; this increases the risk of acute kidney injury 1, 3, 4
• Do not rely solely on MAP; tissue perfusion markers (lactate, urine output, mental status) are equally critical 1
• Do not use vasopressin as monotherapy; it must always be added to norepinephrine 2, 1

Adjunctive Therapy for Refractory Shock

• Consider hydrocortisone 200 mg/day IV if hypotension remains refractory after at least 4 hours of high-dose vasopressor therapy (norepinephrine plus vasopressin) 1, 8
• Steroids should not be initiated at a predetermined vasopressor dose but rather when hemodynamic stability cannot be achieved despite adequate fluid resuscitation and vasopressor escalation 8