Continuous subcutaneous injection of ketamine for cancer pain.

To the Editor: Bain circuits which we presently use are designed with a coloured delivery tube so that kinks or obstructions to the tube will be easily Seen. We received a new Bain circuit which appeared intact, but when it was placed on the anaesthetic machine, it provided no gas flow at the patient end. On examining the circuit, the delivery tube was obstructed and kinked at the proximal end. The obstruction was not visible, as it was inside the opaque connecter at the proximal end of the circuit. This is clearly seen in the radiograph (Figure).