When I was training, we used nitrous oxide on just about every anesthetic. It was easy to use. It was inexpensive. It didn’t tend to effect hemodynamics so it was useful in less stable patients when combined with an opioid. It helped speed induction through the second gas effect. It was not metabolized so renal and liver insufficiency were of less concern.

However, with all of the more recent investigation into reasons for cognitive dysfunction or decline in infants and the elderly following anesthesia, a lot more is now known about the pharmacologic disadvantages of nitrous oxide (1, 2, 3). Continue reading