OBJECTIVE Tracheostomy is frequently required in the treatment of critically ill patients to prevent the complications associated with prolonged translaryngeal intubation. Tracheostomy may facilitate airway suctioning and improve patient comfort in the process of weaning. The purpose of the study was to assess our experience with PDT and to evaluate the complications in comparison with open surgical tracheostomy which is associated with complication rates ranging up to 50%. METHODS PDT was performed using the serial dilational technique described by Ciaglia (percutaneous tracheostomy introducer set, Cook Critical Care) by careful fibreoptic monitoring of the tracheal puncture and the tracheostomy tube insertion. Complications related to the procedure and late effects were recorded. RESULTS 195 PDT were performed in adult intensive-care patients on prolonged mechanical ventilation. In 182 cases (93.4%) placement of the tube was successful without complications. Intraoperative complications occurred in 13 patients (6.6%) including bleeding (5), superficial lesion of the tracheal mucosa (3), pneumothorax (1) and others (4). After decannulation in 132 patients the tracheostoma closed spontaneously and the cosmetic and functional results were good. In 131 cases there was no clinical, radiographic and endoscopic evidence of symptomatic tracheal stenosis. Only in one patient 6 weeks after decannulation a relevant stenosis was seen. In 72 patients after median sternotomy no stomal wound infection and no mediastinitis was observed. CONCLUSIONS PDT is a safe and practicable alternative technique which can be performed in the intensive-care unit with a lower risk of complications than open surgical tracheostomy. Endoscopic guidance prevents serious complications and apparently increases the safety of this procedure.