Tracheal trauma from percutaneous tracheostomy using the Griggs method.

In a safety evaluation study, relative force and distance measurements during percutaneous tracheostomy were recorded using specially monitored Griggs guidewire dilating tracheostomy forceps on 12 cadavers scheduled to undergo postmortem examination the same day. All measurements were recorded in millivolts and were converted to force and distance via appropriate calibration tables. Markedly more force was required for tracheal destruction than for therapeutic tracheal dilation (87.7 N +/- 19 N vs. 31.6 N +/- 17.1 N, p <0.001). Also relatively less force was required for therapeutic tracheal dilation than for dilation of the pretracheal tissues (44.4 N +/- 17.1 N vs. 31.6 N +/- 17.1 N, p <0.05). These results suggest that the Griggs tracheostomy forceps have a reasonable margin of safety in that tracheal destruction is unlikely to occur inadvertently during therapeutic dilation. Second, the dilation of pretracheal tissues can act as useful guide in knowing how much force to apply in a therapeutic dilation.