Changing patterns of airway accidents in intubated ICU patients.

Objective: To document the changes in patterns of airway accidents in intubated patients.
Design: Prospective recording of all airway accidents over two periods: 1994-1997 and 1998-1999.
Patients: Ventilated patients (5,046) intubated for 9,289 days over 4 years (1994-1997) and 2,932 ventilated patients intubated for 6,339 days over 2 years (1998-1999).
Measurements: The incidence and pattern of airway accidents over a 2-year period were compared to an earlier similar analysis done in the previous 4 years.
Results: The total accident rate in the 1994-1997 period was 36 in 5,046 patients over 9,289 intubated-patient days. The total accident rate in the period 1998-1999 was 20 in 2,932 patients over 6,339 intubated-patient days. The frequency of blocked tracheal tube increased to equal that of unplanned extubation (UE) of endotracheal tube (ETT) as the commonest airway accident. There were nine episodes of blocked tracheal tube in the two current years compared to four in the previous 4 years and there were nine episodes of UE in the two current years compared to 15 in the previous 4 years. There were a total of 18 ETT accidents in 2,930 patients over 5,309 ETT days compared to a total of two tracheostomy accidents in 67 patients over 1,030 tracheostomy days.
Conclusions: We noted a change of the pattern of airway accidents. We noted an increasing trend in the incidence of blocked tracheal tubes, associated with an increased duration of heat and moisture exchanger-filters use. We also noted that the incidence of tracheostomy tube accidents was similar to that of ETT accidents in the current study, unlike the earlier study where tracheostomy tube accidents were more frequent than ETT accidents. This was due to the elimination of tracheostomy tube displacements during the later study period. We associated this with the use of adjustable tracheostomy length tubes.