Co-induction of anaesthesia: day-case surgery

Area of Science:

• Anesthesiology
• Pharmacology

Background:

• Co-induction of anesthesia, the use of two or more drugs to induce anesthesia, was initially described in 1986.
• Unplanned co-induction by non-anesthetists led to fatalities due to synergistic drug effects.
• Planned co-induction is now used by anesthesiologists to optimize anesthesia phases through drug interactions.

Purpose of the Study:

• To review the current practices of co-induction of anesthesia.
• To highlight the benefits of combining midazolam with propofol for induction.
• To discuss the health economics associated with reduced propofol dosage.

Main Methods:

• Review of current literature on co-induction techniques.
• Analysis of drug interactions, particularly synergism, between agents like midazolam, propofol, and opioids.
• Evaluation of the impact of co-induction on anesthesia phases and patient recovery.

Main Results:

• Combining midazolam and propofol reduces the risk of awareness and the required propofol dose, minimizing side effects and costs.
• Pre-administration of midazolam (around 2 mg) does not significantly delay recovery in healthy adults.
• Co-induction with midazolam, propofol, and opioids can reduce bradycardia risk but may increase post-operative nausea and vomiting.

Conclusions:

• Planned co-induction, especially with midazolam and propofol, offers improved anesthesia induction, maintenance, and recovery.
• This technique is particularly beneficial for day-case anesthesia, enhancing patient safety and potentially reducing healthcare costs.
• Further research into agents like ketamine and alpha-2 agonists may expand co-induction applications.