Tracheal rupture during percutaneous tracheostomy. Safety aspects of the Griggs method

Abstract

Despite being used in many intensive care units in the UK,1 little is known about the safety of the guide wire dilating forceps (GWDF) technique of percutaneous tracheostomy. A previous evaluation study of the GWDF noted a definite learning curve in knowing how much force to exert through the forceps to establish a therapeutic dilation.2 The aim of this study was to determine how similar the force required for therapeutic dilation of the trachea is to the force required to cause tracheal disruption using the GWDF. Percutaneous dilational tracheostomy using the GWDF was performed on 12 cadavers scheduled to undergo post mortem the same day. Dilational forces and distances were measured as electric signals (mV) using specially monitored forceps, the change in mV being proportional to the change in both distance and force. Three related force and distance measurements were recorded. (1) Dilation of the pretracheal tissues. (2) Therapeutic dilation of the trachea. The trachea was dilated to allow easy insertion of a 7-mm internal diameter low profile cuffed tracheostomy tube (Mallinckrodt, UK). (3) Destructive dilation of the trachea. The trachea was dilated until there was a distinct give and the investigator felt that disruption had occurred to the trachea. Forces were compared using Student'st-test. The force required for tracheal destruction was more than twice that required for therapeutic dilation 735 ± 140vs 296 ± 80 mV (P The marked differences seen between the forces required for therapeutic and destructive dilation of the trachea offer a reasonable margin of safety when using the GWDF. Dilating the pretracheal tissues is a useful guide as less force should then be used to dilate the trachea.