What is the recommended dosage and administration of propofol (propofol) infusion for a burr hole procedure?

Propofol Infusion for Burr Hole Procedure

For burr hole procedures, initiate propofol with a slow induction bolus of 0.5-1.5 mg/kg administered over 20-30 seconds (approximately 20 mg every 10 seconds), followed by a continuous infusion of 50-150 mcg/kg/min, titrated to maintain adequate sedation while avoiding rapid bolus administration that can cause severe cardiorespiratory depression. 1

Induction Dosing

Slow induction is critical for burr hole procedures to maintain hemodynamic stability:

• Administer 0.5-1.5 mg/kg as an initial bolus at a rate of approximately 20 mg every 10 seconds until induction onset 1
• Avoid rapid bolus administration, which can result in hypotension, apnea, airway obstruction, and oxygen desaturation 1
• The onset of action occurs within 30-45 seconds (arm-brain circulation time) 2

For elderly, debilitated, or ASA-PS III-IV patients:

• Reduce the induction dose to approximately 80% of standard adult dosing 1
• Extend administration time to 3-5 minutes 1
• Rapid bolus doses should never be used in these populations 1

Maintenance Infusion

Following induction, immediately transition to continuous infusion:

• Start at 100-200 mcg/kg/min for the first 10-15 minutes 1
• Decrease by 30-50% after the initial period to 50-100 mcg/kg/min for ongoing maintenance 1
• When combined with opioids (recommended for painful procedures), maintenance rates can be reduced to 50 mcg/kg/min minimum 1

Intermittent bolus technique (alternative):

• Administer 25-50 mg increments when vital signs indicate response to surgical stimulation 1
• This method increases risk of respiratory depression and prolonged recovery compared to continuous infusion 1

Combination Therapy for Painful Procedures

Propofol should be combined with opioid analgesics for burr hole procedures due to its minimal analgesic properties:

• Administer fentanyl 50-75 mcg or equivalent opioid prior to propofol induction 3
• Consider adding midazolam 0.5-1.0 mg for enhanced amnesia 3
• Combined therapy allows lower propofol doses (reducing cumulative dose to 52-66 mg for similar procedures), minimizing cardiorespiratory depression 3
• Opioid premedication (morphine 0.15 mg/kg equivalent) decreases necessary propofol maintenance infusion rates 1

Critical Monitoring Requirements

Continuous monitoring is mandatory throughout propofol administration:

• Pulse oximetry for early detection of respiratory depression 3
• Continuous blood pressure monitoring, as propofol causes dose-dependent decreases in blood pressure and cardiac output through decreased peripheral vascular resistance 2, 1
• ECG monitoring, particularly in patients with cardiovascular disease 3
• Capnography should be considered for early detection of hypoventilation 3

Common Pitfalls and Safety Considerations

Respiratory depression is the primary concern:

• Propofol causes dose-dependent respiratory depression and potential apnea 3, 2
• In pediatric studies, 8-11.6% of patients experienced oxygen saturation below 90-93%, though most responded to simple interventions 3
• Have bag-valve-mask ventilation immediately available 3

Cardiovascular effects:

• Propofol decreases cardiac output, systemic vascular resistance, and blood pressure 2
• Transient hypotension is common but rarely requires intervention in healthy patients 3
• In patients with cardiac disease, propofol may cause greater myocardial depression than thiopentone, potentially creating oxygen supply-demand imbalance 4

Avoid co-administration with vasodilators:

• Never administer propofol with sodium nitroprusside through the same Y-site due to severe additive hypotensive effects 5
• Use separate dedicated IV lines if both medications are required 5
• Have vasopressors readily available 5

Duration Considerations

Propofol's pharmacokinetic profile makes it ideal for burr hole procedures:

• Duration of effect is 4-8 minutes after single bolus dose 2
• Rapid recovery occurs even after prolonged infusions due to efficient redistribution and hepatic clearance 6, 7
• Recovery is faster than midazolam, with more predictable emergence times 6

For procedures exceeding 48 hours or requiring doses >4 mg/kg/h:

• Monitor for propofol infusion syndrome (PRIS), characterized by metabolic acidosis, rhabdomyolysis, cardiac arrhythmias, and potential death 8
• Check serum triglycerides during prolonged infusions (>3 days) due to lipid vehicle 6

Special Populations

Contraindications and allergies:

• Avoid in patients with egg, soy, or sulfite allergies (formulation contains 10% soybean oil and 1.2% egg phosphatide) 2
• Not contraindicated in sulfonamide allergy 2

Dosage adjustments:

• Elderly patients show marked sensitivity; reduce doses to 80% of standard adult dosing 1, 4
• Cirrhosis or renal insufficiency do not significantly affect pharmacokinetics 2