What are the dosing recommendations for remifentanil and propofol in TIVA?

From the Guidelines

For total intravenous anesthesia (TIVA), remifentanil and propofol should be administered via target-controlled infusion (TCI) pumps, targeting effect-site concentrations of 1-3 ng/mL for remifentanil and 0.5-1 μg/mL for propofol, as recommended in the most recent guidelines 1. The dosing recommendations for remifentanil and propofol in TIVA are crucial for ensuring patient safety and effective anesthesia.

• Remifentanil, an ultra-short-acting opioid, provides analgesia with rapid offset, allowing for precise titration and quick emergence.
• Propofol, on the other hand, provides hypnosis, and its dosing should be adjusted based on patient factors, including age, weight, comorbidities, and surgical stimulation level. Key considerations for dosing include:
• Avoiding bolus dosing for remifentanil to prevent respiratory depression 1.
• Using caution with propofol doses in excess of 1.5 μg/mL to avoid over-sedation and hypoventilation, particularly with concomitant opioid use 1.
• Adjusting dosing for elderly patients and those with compromised cardiovascular function, typically reducing doses by 30-50% 1. The combination of remifentanil and propofol works synergistically, allowing for precise titration and quick emergence, making it an effective choice for TIVA.
• Dedicated IV lines or one-way valves are required to prevent backflow, and infusion pumps are necessary for accurate delivery.
• The medications should be titrated to effect, taking into account the patient's response to surgical stimulation and anesthesia. As recommended in the guidelines, targeting effect-site concentrations of 1-3 ng/mL for remifentanil and 0.5-1 μg/mL for propofol is crucial for ensuring optimal anesthesia and minimizing adverse effects 1.

From the FDA Drug Label

Remifentanil hydrochloride for injection is synergistic with other anesthetics; therefore, clinicians may need to reduce doses of thiopental, propofol, isoflurane, and midazolam by up to 75% with the coadministration of Remifentanil hydrochloride for injection.

Table 1: Dosing Guidelines in Adults – General Anesthesia and Continuing as an Analgesic into the Postoperative Care Unit or Intensive Care Settinga ... Maintenance of anesthesia with: ... Propofol (100 to 200 mcg/kg/min) 0.25 0.05 – 2 1

The dosing recommendations for remifentanil and propofol in TIVA are as follows:

• Remifentanil: 0.25 mcg/kg/min, with a range of 0.05-2 mcg/kg/min, and supplemental IV bolus doses of 1 mcg/kg.
• Propofol: 100 to 200 mcg/kg/min. When coadministering remifentanil with propofol, the dose of propofol may need to be reduced by up to 75% 2.

From the Research

Dosing Recommendations for Remifentanil and Propofol in TIVA

The dosing recommendations for remifentanil and propofol in Total Intravenous Anesthesia (TIVA) can vary depending on the specific procedure, patient population, and desired level of anesthesia. Here are some key points to consider:

• A study published in 2005 3 used a combination of remifentanil (10 microg.ml(-1)) and propofol (10 mg.ml(-1)) for TIVA in pediatric patients undergoing magnetic resonance imaging (MRI).
• Another study from 1998 4 compared TIVA with propofol and remifentanil to desflurane-N2O anesthesia in pediatric patients undergoing ENT surgery, but did not specify the exact dosing regimen.
• A dose-response study published in 2012 5 found that the effective dose of remifentanil for acceptable intubating conditions during propofol induction without neuromuscular blockade was 1.40 μg/kg (ED50) and 2.40 μg/kg (ED95).
• A study from 2001 6 used a combination of remifentanil (0.5 g/kg b.w. loading dose, followed by 0.5 ug/kg/min infusion) and propofol (6 mg/kg/h infusion) with midazolam co-induction for TIVA in laparoscopic cholecystectomy.
• A study published in 1998 7 investigated the effect of different doses of remifentanil on respiratory depression and somatic response at incision during spontaneous ventilation anesthesia with propofol, and found that maintenance infusions of remifentanil (0.025-0.05 microgram kg-1 min-1) and propofol (6 mg kg-1 h-1) were likely to be adequate for spontaneous ventilation.

Key Considerations

Some key considerations when using remifentanil and propofol for TIVA include:

• The need for careful titration of the doses to achieve the desired level of anesthesia while minimizing side effects
• The importance of monitoring respiratory function and adjusting the doses accordingly
• The potential for respiratory depression with higher doses of remifentanil
• The need for individualized dosing regimens based on patient factors such as age, weight, and medical history.