The technique for freeing adherent ventricular catheters is described in which a Bugbee wire, insulated except for the tip, is used to deliver a monopolar coagulating current to the tissue adherent to the drainage holes of the catheter. This may have some advantage over the use of an uninsulated metal cannula for delivery of a unipolar diathermy cutting current. The technique described has permitted effective and safe removal of adherent ventricular catheters.