Thirty‐five patients who had undergone uncomplicated cardiac surgery were randomly allocated to receive either Entonox or isoflurane 0.25% in Entonox as inhalational analgesia for the removal of their two chest drains. The gases were presented premixed in high‐pressure cylinders and were self‐administered by means of a demand valve. The removal of the second drain was more painful than the first but that pain was better controlled by isoflurane 0.25% in Entonox than by Entonox alone.