Fracture of the outer varnish layer of a gum elastic bougie

A 50-year-old woman presented for a laparoscopic cholecystectomy. A grade 3 Cormack and Lehane view was obtained at laryngoscopy. A 15-Ch, 60-cm Eschmann bougie was used to assist intubation. The distal end of the bougie was gently bent forwards in an attempt to further angulate the distal segment. This caused a fracture of the outer layer of the bougie at 12 cm from the distal end. The fracture was immediately apparent. The bougie was bent at an angle of less than 90°. An attempt was made to pass this bougie into the trachea but this was unsuccessful. The operating department assistant went to an adjoining theatre to obtain a new undamaged bougie. The new bougie was successfully inserted into the trachea resulting in an uneventful tracheal intubation. The original bougie was subjected to further evaluation. Gentle bending of the distal 12-cm segment resulted in a further fracture of the outer layer at 5 cm from the tip. Bending of the proximal section of the bougie at an angle of 180° did not result in any further fracture of the outer coating. It appears therefore that there were localised areas of weakness in the outer layer of the bougie. The damaged bougie was subsequently discarded. A similar problem occurred recently. The trainee was unable to pass a bougie into the trachea but was unaware that the bougie was defective. The consultant then attempted to intubate the trachea. At that time it was noted that the outer layer of the bougie was fractured 10 cm from the tip. The bougie was changed and a further attempt at intubation was successful. Attempts to gently bend both the distal and the proximal sections of this bougie resulted in no further trauma to its outer layer. There has been a previous report of failed intubation with a defective bougie which resulted in a critical incident [1]. In that case, the outer varnish coating broke at a distance of 3 cm from the tip of the bougie. Intubation when using the bougie was unsuccessful but was eventually successful with the help of a stylet in the tracheal tube. The defect in the bougie was not recognised until later. Considering the frequency of use of these devices, it is clear that either this problem is very rare or that incidences of fracture of the outer varnish coating go unreported. Bougies vary considerably in their physical properties. Some are rigid and difficult to bend and some are very floppy. In the manufacturing process, the inner braided layer is impregnated with varnish and the bougie is then placed in an oven to dry. This process is repeated up to five times. There is therefore an art as well as a science component in the manufacturing process. Each bougie is supposed to be used up to five times and then it should be discarded. It appears that this advice is probably ignored by virtually all users. This is partly because there is normally no formal record kept of usage of the device. Also the device will usually function perfectly well for considerably more than five times. What is the indication for changing an old bougie for a new one in clinical practice? This is far from clear. It is also clear that the manufacturers instructions in respect of sterilisation after use are often ignored [2]. In a recent unpublished Cardiff audit of 200 uses of the bougie, there was one case of initial failure because the bougie was judged to be too rigid and one failure where the bougie was judged to be too floppy. In both cases, successful intubation resulted when the bougie was changed. There was only one final case of intubation failure with the bougie in the 200 cases. The intubation success rate was 16/24 cases (66%) when the bougie was used in an Australian series [3]. The comparative intubation success data with use of an introducer in their series was 6/15 cases (40%). It is not clear why our results are so different from theirs. It is clear, however, that there is very little prospective data available on the effectiveness of this device. There are of course a number of case reports and other data supporting its use in the management of cases of unsuspected difficult intubation. We agree with Robbins [1] that bougies should be inspected before use. We would also recommend that users check that they are happy with the rigidity of the chosen bougie and that a spare bougie is readily available. There are no data available on optimum rigidity but it appears that the manufacturers generally get it about right because our incidence of failure was only 0.5%.