What are the recommended doses of propofol and remifentanil for sedation during coronary angiography in a typical adult patient (approximately 70 kg, ASA II‑III, normal renal and hepatic function, and no severe left ventricular dysfunction)?

Propofol and Remifentanil Dosing for Coronary Angiography

For coronary angiography in a typical adult, start with remifentanil 0.125 µg/kg/min for 2 minutes, then reduce to 0.05 µg/kg/min continuous infusion, combined with propofol boluses of 10-20 mg every 20-30 seconds until adequate sedation is achieved. 1

Initial Dosing Strategy

Remifentanil Administration

• Begin with 0.125 µg/kg/min for 2 minutes as the loading phase 1
• Reduce to 0.05 µg/kg/min for maintenance infusion 1
• Avoid bolus dosing of remifentanil entirely—the Difficult Airway Society specifically warns that bolus administration markedly increases respiratory depression risk during conscious sedation for coronary angiography 1

Propofol Administration

• Administer 10-20 mg boluses every 20-30 seconds until target sedation level is reached 1, 2
• Allow adequate time between doses (20-30 seconds minimum) to assess peak effect before giving additional medication 1
• Avoid rapid bolus dosing to prevent hypotension and respiratory depression 1

For a 70 kg Patient (Practical Calculation)

• Remifentanil loading: 0.125 µg/kg/min × 70 kg = 8.75 µg/min for 2 minutes
• Remifentanil maintenance: 0.05 µg/kg/min × 70 kg = 3.5 µg/min continuous
• Propofol: 10-20 mg boluses titrated to effect, typically totaling 35-100 mg for the procedure 3, 2

Alternative Target-Controlled Infusion (TCI) Approach

If using TCI pumps (preferred by some centers for more precise control):

• Remifentanil effect-site concentration: 1-3 ng/mL 1
• Propofol effect-site concentration: 0.5-1 µg/mL 1
• This TCI approach provides more stable drug levels and reduces apnea incidence compared to manual bolus administration 3

Critical Safety Considerations

Synergistic Respiratory Depression

The combination produces respiratory depression beyond either agent alone—this is the most important safety concern. 4, 1 The American Society of Anesthesiologists explicitly notes that propofol combined with remifentanil produces deeper sedation with increased respiratory depression risk compared to either drug used separately. 1

Hemodynamic Effects

• Expect hypotension after propofol loading—mean arterial pressure typically drops 15-35% 5, 6
• Propofol causes dose-dependent decreases in cardiac output and systemic vascular resistance 3
• In cardiac patients, propofol (2 mg/kg bolus) decreased mean arterial pressure from 80 mmHg to 67.5 mmHg within minutes 5
• The hypotension typically responds rapidly to dose reduction and rarely requires intervention beyond fluid administration 3, 7

Zero Analgesic Properties

Propofol provides absolutely no analgesia—remifentanil is essential for the painful aspects of vascular access and catheter manipulation during coronary angiography. 1, 3, 2 This is a common pitfall where inadequate analgesia leads to patient movement or hypertensive responses despite adequate sedation.

Mandatory Monitoring Requirements

You must have continuous monitoring with a dedicated provider who performs no other tasks during sedation:

• Pulse oximetry (continuous) 1, 3, 2
• Blood pressure (every 2-5 minutes minimum) 4, 1, 3
• Heart rate (continuous) 4, 1, 3
• Capnography (continuous—essential for early detection of hypoventilation before desaturation occurs) 1
• Supplemental oxygen (mandatory in all cases) 1, 3, 2
• Maintain vascular access throughout and until cardiorespiratory depression risk has resolved 1

Immediate Availability Requirements

Have at bedside before starting:

• Naloxone for remifentanil reversal 1
• Bag-valve-mask and airway management equipment 1
• Suction 1
• Approximately 5-10% of patients will experience transient oxygen desaturation <90% requiring jaw thrust or brief bag-mask ventilation 2

Dose Reduction Strategies

Target moderate rather than deep sedation to improve the safety profile—this is critical in the cardiac catheterization laboratory where you need patient cooperation for breath-holding during imaging. 1

When combining propofol with remifentanil:

• Reduce propofol doses by 50-75% from what you would use for propofol monotherapy due to synergistic effects 1
• The combination allows cumulative propofol doses of only 35-100 mg for most procedures versus 200-300 mg when used alone 4, 3

Common Pitfalls to Avoid

1. Administering propofol loading doses in hemodynamically unstable patients—use smaller incremental doses (5-10 mg) in patients with reduced ejection fraction or ongoing ischemia 3

2. Not waiting between doses—propofol's peak effect occurs at 90-120 seconds; dosing faster leads to stacking and oversedation 1

3. Using remifentanil boluses—always use infusion only to avoid severe respiratory depression 1

4. Inadequate analgesia—remember propofol has zero analgesic effect; if the patient is moving or hypertensive despite appearing sedated, increase remifentanil, not propofol 1, 3, 2

5. Failing to recognize propofol infusion syndrome risk—though rare in short procedures, avoid rates >70 µg/kg/min if the case extends beyond expected duration 3

Evidence Quality Note

The dosing recommendations come from the American Society of Anesthesiologists guidelines synthesized in Praxis Medical Insights 1, which represents the highest quality and most recent (2026) evidence available. The gastroenterology literature 4 provides supportive data on combination sedation but uses different drug combinations (fentanyl/midazolam) that are less applicable to coronary angiography. The cardiac anesthesia research 5, 6, 7 confirms hemodynamic effects but used higher induction doses (2 mg/kg bolus) than currently recommended for procedural sedation.