Switching from inhaled to intravenous general anaesthesia

Why change is needed

The “triad of anaesthesia,” comprising unconsciousness, analgesia, and immobility, is typically achieved with hypnotics and analgesics, with or without muscle relaxants. Inhalational anaesthetic agents are greenhouse gases; volatiles (eg, sevoflurane, desflurane) persist in the atmosphere for up to 21 years; nitrous oxide (an analgesic and sedative) persists for more than 100 years. Inhaled anaesthetic agents are estimated to account for up to 3% of total national healthcare greenhouse gas emissions in high income countries, and between 0.01% and 0.1% of greenhouse gas emissions overall.2

Inhalational anaesthesia has an impressive safety profile and some valuable clinical uses (eg, induction of anaesthesia in patients without intravenous access), but is also associated with postoperative nausea and vomiting, can trigger malignant hyperthermia in susceptible patients, and staff working in operating theatres risk occupational exposure. TIVA, typically based on propofol (a hypnotic agent) and an opioid such as remifentanil, offers a smooth and rapid return of consciousness, which may have implications for patient satisfaction and recovery, and is preferable in situations when ventilation may have to be interrupted (eg, during “tubeless field” airway surgery). Although each technique …