| Nolan JP, 1993, UK | 157 patients undergoing elective surgery | PRCT | Number of grade 3 views in neutral position | 34/157 (22%) | Small number of truly difficult laryngoscopies in whom differences are likely to be the greatest |
| | | Median time for intubation | 20 secs for direct intubation v 25 seconds for use of the bougie |
| No grade 4 views |
| Patients were intubated in the neutral c-spine position | | Success rate for intubation | 5/78 (6.4%) direct intubation patients could not be intubated (they were subsequently intubated using the bougie). 0/79 patients could not be intubated using the bougie |
| Patients were either intubated direct (just with the ETT) or using a bougie. | | Number of patients requiring prolonged time for intubation (>45 seconds) | 11 in direct visualised group v none in the bougie group. |