What is the recommended dose of propofol (intravenous anesthetic agent) for induction?

Propofol Induction Dosing

For healthy adults under 55 years (ASA I-II), administer 2-2.5 mg/kg propofol for induction, titrated as 40 mg boluses every 10 seconds until loss of consciousness. 1

Standard Adult Dosing by Patient Category

Healthy Adults (ASA I-II, <55 years)

• Dose: 2-2.5 mg/kg when unpremedicated or premedicated with oral benzodiazepines or intramuscular opioids 1
• Administer as 40 mg boluses every 10 seconds, titrated to clinical response 1
• This represents the FDA-approved standard for this population 1

Elderly, Debilitated, or ASA III-IV Patients

• Dose: 1-1.5 mg/kg (approximately 20 mg every 10 seconds) 1
• Critical: Avoid rapid bolus administration as this significantly increases risk of hypotension, apnea, airway obstruction, and oxygen desaturation 1
• The reduced dose accounts for decreased clearance and higher blood concentrations in this population 1

Neurosurgical Patients

• Dose: 1-2 mg/kg administered as slow boluses of 20 mg every 10 seconds 1
• Slower titration is mandatory in this population to minimize hemodynamic instability 1

Cardiac Anesthesia Patients

• Dose: 0.5-1.5 mg/kg at a slow rate of approximately 20 mg every 10 seconds 1
• Rapid bolus induction must be avoided in cardiac patients 1
• Propofol causes dose-dependent decreases in cardiac output, systemic vascular resistance, and arterial pressure 1

Combination Therapy Dosing

With Opioids and/or Benzodiazepines

• Dose: 10-20 mg initial bolus when combined with these agents 2, 3
• The American College of Physicians specifically recommends reducing to 10-15 mg in elderly patients when using combination therapy 2
• Combination therapy allows 50-75% reduction in propofol requirements while maintaining excellent intubating conditions 3
• Critical synergistic effect: Propofol combined with opioids produces respiratory depression exceeding either agent alone 3

Obstetric Rapid Sequence Induction

• The Obstetric Anaesthetists' Association recommends propofol over thiopental for rapid sequence induction 4
• Propofol suppresses airway reflexes more effectively than thiopental, advantageous if intubation fails 4
• Avoid inappropriately low doses (<4 mg/kg equivalent) as NAP5 identified this as a factor in awareness during obstetric anesthesia 4

Modified Rapid Sequence Induction (COVID-19 Context)

• Chinese Society of Anesthesiology recommends midazolam 2-5 mg with etomidate 10-20 mg or propofol if hemodynamics allow 4
• Add fentanyl 100-150 mcg or sufentanil 10-15 mcg to suppress laryngeal reflexes 4

Pediatric Dosing

Children 3-16 Years (ASA I-II)

• Dose: 2.5-3.5 mg/kg when unpremedicated or lightly premedicated 1
• Younger pediatric patients require higher induction doses than older pediatric patients within this range 1
• Research confirms infants 1-6 months require ED50 of 3.0 mg/kg, while children 10-16 years require 2.4 mg/kg 5
• Lower dosage recommended for ASA III-IV pediatric patients 1

Critical Safety Considerations

Hemodynamic Monitoring

• Mandatory continuous monitoring: heart rate, blood pressure, and pulse oximetry during all propofol administration 2, 6, 3
• Propofol causes dose-dependent decreases in cardiac output, systemic vascular resistance, and arterial pressure 2, 6, 3, 1
• Approximately 5-7% of patients experience transient desaturation below 90% 2, 3

Respiratory Depression

• Have airway management equipment immediately available 3
• Capnography is required for early detection of hypoventilation 3
• Supplemental oxygen administration is necessary 2, 3
• Propofol induces significant respiratory depression characterized by reduced respiratory rate 2

Vasopressor Availability

• Have vasopressors immediately available (ephedrine or metaraminol) to treat hypotension 6
• Consider elevation of lower extremities when additional fluid therapy is contraindicated 6

Common Pitfalls to Avoid

Dosing Errors

• Do not administer loading doses in hemodynamically unstable patients 2
• Avoid rapid bolus administration, particularly in elderly, cardiac, or neurosurgical patients 1
• Real-world data shows 64.8% of patients over 65 receive doses above the recommended geriatric range, with 73.8% of those aged 65-69 receiving excessive doses 7

Drug Interactions

• Account for premedication effects: opioid and benzodiazepine premedication significantly influences propofol requirements 1
• Morphine premedication (0.15 mg/kg) with nitrous oxide decreases necessary propofol doses compared to lorazepam premedication 1

Analgesia Considerations

• Propofol has zero analgesic properties - always consider adding analgesics for painful procedures 2, 3
• For procedures like bone marrow biopsies, consider adding subdissociative ketamine (0.25-0.5 mg/kg) which reduces total propofol requirements and shortens recovery time 8

Contraindications

• Avoid in patients with egg, soy, or sulfite allergies 2, 6
• Propofol is NOT contraindicated in sulfonamide allergy 6

Propofol Infusion Syndrome (PRIS)

• Monitor for PRIS, especially with doses >70 mcg/kg/min or prolonged infusions 2
• Account for propofol's caloric contribution (1.1 kcal/ml from lipid emulsion) in nutritional calculations 2