Percutaneous dilational tracheostomy (PDT) has replaced conventional tracheostomy for long-term intubated patients in many intensive care units (ICUs). In a prospective study carried out between September 1994 and August 1996, 76 patients underwent PDT. In 41 patients, PDT was performed "blind." In 35 patients it was executed with simultaneous bronchoscopic monitoring. The type and rate of complications of the two techniques were compared. Comparing the groups with and without bronchoscopy, the perioperative complication rate was equivalent (7% vs 6%); however, more severe complications occurred in the group without bronchoscopy (one death due to tension pneumothorax, two cases of perforating the rear tracheal wall) than in the group with bronchoscopy (two cases of intratracheal hemorrhage). PDT is a suitable bedside method for ICU patients undergoing long-term ventilation. Simultaneous endoscopy minimizes the severity of complications.