What antihypertensive can be given to a post-operative patient with hypertension after noradrenaline (norepinephrine) was stopped due to hypotension?

Antihypertensive Management in Post-Operative Patients After Norepinephrine Discontinuation

For a post-operative patient with hypertension after norepinephrine was discontinued due to hypotension, nicardipine is the preferred antihypertensive agent due to its rapid onset, short duration of action, and favorable hemodynamic profile. 1, 2

First-Line Medication Options

Nicardipine (IV)

• Starting dose: 5 mg/hr IV infusion
• Titration: Increase by 2.5 mg/hr every 5-15 minutes
• Maximum dose: 15 mg/hr
• Benefits:
  • Rapid onset of action (therapeutic response within 12 minutes for post-operative hypertension) 2
  • Easily titratable with predictable dose-response 3
  • Selective vasodilation with minimal effects on heart rate 4
  • Particularly beneficial in patients with renal dysfunction (no dose adjustment needed) 5
  • Average maintenance dose for post-operative hypertension: 3 mg/hr 2

Alternative Options Based on Specific Comorbidities

For patients with tachycardia:

• Labetalol (IV)
  • 10-20 mg IV bolus over 2 minutes
  • Can be repeated or doubled every 10 minutes
  • Maximum total dose: 300 mg 5
  • Combined alpha/beta blocking properties make it suitable for post-operative patients 5

For patients with coronary artery disease:

• Nitroglycerin (IV)
  • Starting dose: 5 μg/min
  • Titration: Increase by 5 μg/min every 3-5 minutes 5
  • Particularly beneficial for patients with acute coronary syndromes 1

For patients with acute pulmonary edema:

• Clevidipine (IV) or Nitroglycerin (IV)
  • Beta-blockers are contraindicated in this setting 1

Important Considerations

1. Evaluate for reversible causes before administering antihypertensives:

   • Pain
   • Anxiety
   • Urinary retention
   • Hypoxemia
   • Hypothermia
   • Volume status (overload or depletion) 5

2. Medication continuation principles:

   • Continue beta-blockers if patient was on them chronically 1, 5
   • Consider discontinuing ACE inhibitors/ARBs perioperatively 1, 5
   • Never abruptly discontinue beta-blockers or clonidine due to risk of rebound hypertension 1, 5

3. Monitoring:

   • Monitor blood pressure every 5-15 minutes during titration
   • Monitor heart rate closely, especially with beta-blockers 5
   • Avoid excessive BP lowering which can cause organ hypoperfusion 5

Cautions and Contraindications

• Avoid beta-blockers in patients with:

  • Moderate-to-severe heart failure with pulmonary edema
  • Bradycardia (<60 bpm)
  • Hypotension (SBP <100 mmHg)
  • Poor peripheral perfusion
  • Second or third-degree heart block
  • Reactive airways disease 1

• Never start beta-blockers on the day of surgery in beta-blocker-naïve patients 1, 5

Clinical Pearls

• Nicardipine has been shown to control post-operative hypertension more rapidly than nitroglycerin (10.5 ± 2.5 min vs 18.7 ± 2.8 min) 4
• Nicardipine requires fewer dose adjustments to achieve therapeutic response compared to nitroglycerin 4
• The incidence of hypotensive episodes is lower with nicardipine (5%) compared to nitroglycerin (30%) 4
• For patients transitioning from IV to oral therapy, consider the same class of medication that was effective intravenously