Tracheal stenosis is a common complication after percutaneous dilational tracheostomy (PDT). In 1992, Ciaglia and Graniero  were the first to report any long-term follow-up of patients who had PDT and initially reported no such long-term complication. Subsequently, however, they reported that tracheal stenosis had developed in two of the 254 patients . Another early study reported an incidence of tracheal stenosis of 18% , but more recent reports suggest an increased occurrence with antegrade techniques, and Norwood et al. found tracheal stenosis (defined as a reduction of greater than 10% of the tracheal lumen) in 15 of 48 (31%) patients.
A second recognized complication of PDT that may also be more common with antegrade techniques is tracheal ring fracture (TRF), and this has been reported to occur in seven of 54 patients when the new PercuTwist method was used . TRFs leave exposed cartilage within the trachea, and this is a potent stimulus for granulation tissue formation, which may subsequently increase the risk of tracheal stenosis. There has not been any study to investigate such a relationship, and we have performed a single-centre, nonrandomized, retrospective observational study to assess whether TRF during antegrade PDT is associated with an increased risk of tracheal stenosis.
We examined the records of every antegrade PDT performed in our unit over a 26-month period. Two single-step techniques were used in our mixed medical–surgical level 3 critical care unit in a university-affiliated hospital. These were the Blue Rhino (Cook Medical, Bloomington, Indiana, USA) single-step tapered dilator technique derived from Cialia's multidilational PDT in 1992 and the PercuTwist (Rusche, Kernen, Germany) screw-like dilator first described by Frova and Quintel  in 2002. The choice of technique was left to the individual consultant intensivist performing the procedure.
All percutaneous tracheostomies were performed under bronchoscopic guidance, and a record was kept of patients' age, sex, timing of procedure and of any complications. A specific record was made documenting whether or not a TRF was observed at the time of the PDT. All patients for whom a TRF was identified and who survived to hospital discharge were referred for a follow-up appointment with a consultant ear, nose and throat (ENT) surgeon and subsequently underwent an assessment to identify whether tracheal stenosis was present. This clinical assessment included questioning to identify the presence of symptoms and direct visualization of the tracheal lumen by fibreoptic nasendoscopic examination.
A total of 207 patients underwent percutaneous tracheostomy in the 26 months; of these, 132 patients had the PercuTwist technique and 75 had the Blue Rhino technique. A total of 16 tracheal fractures were recorded: four in the Blue Rhino technique group and 12 in the PercuTwist technique group. TRF was thus a complication of both techniques but was more common with the PercuTwist method. The risk of TRF is 5.3% in the Blue Rhino technique group and 9.1% in the PercuTwist group (P value 0.33) giving a risk ratio of 0.59 (95% confidence interval 0.20–1.75).
Ten out of the 16 patients who had TRFs survived to undergo ENT assessment at a mean time of 8.8 months (range 7.2–11.1) after the PDT had been performed. There was no clinical, symptomatic or endoscopic evidence of tracheal stenosis in any of these patients. Laryngotracheoscopy revealed an anterior mucosal ridge in one patient, but there was no significant stenosis. Table 1 summarizes our results.
Although TRF has been noted as a complication of several techniques of percutaneous tracheostomy, our study could find no evidence of long-term clinical complications. There was no clinical or endoscopic evidence of tracheal stenosis in any of the surviving patients who had TRFs.
The presence of TRF has been associated with complications such as migration of cartilage fragments  and difficult endotracheal intubation with puncture of the endotracheal tube cuff . There has been no reported causal relationship between TRF and tracheal stenosis. Other factors have been associated with the development of tracheal stenosis, and these include a prolonged hospital stay, a long period of endotracheal intubation prior to PDT and high cranial placement of the tracheostomy tube . In the study quoted previously by Norwood et al., there were no tracheal fractures in the group which was ultimately shown to have a 31% incidence of tracheal stenosis, so it would appear that the majority of stenotic complications develop in the absence of TRFs after PDT. Both Walz and Schmidt  and Van Heurn et al. found cadaveric evidence of tracheal stenosis following TRF, but this was related in both series to high tracheal puncture (and in two of their cases there was cricoid fracture). Chin Ho et al. report one cause of early tracheomalacia following TRF after percutaneous tracheostomy, though this is the only in-vivo evidence linking TRF to clinically significant sequelae. Finally, the tertiary referral study by Raghuraman et al. looking at patients requiring tracheal reconstruction following tracheostomy found that the percutaneous group had significantly more cranial stenosis that occurred earlier than the surgical group. In our study of patients with TRFs, there were no high placements of the tracheostomy. This along with early decannualation may explain why we have no evidence of tracheal stenosis in our cohort. A further explanation may be that we performed endoscopy too early after PDT and that tracheal stenosis may develop at a later stage. Our timing of assessment is comparable with previous studies such as Cobean et al. (mean 7.5 months, range 1–18), which did identify tracheal stenosis at an early stage. In Norwood's study, however, endoscopy was performed at 30 months (range 3–80 months) and this may explain why the incidence of stenosis was so high.
With regard to the incidence of TRF with the two antegrade techniques of PDT, it appears that using the PercuTwist set results in a greater incidence than the Blue Rhino technique. This is consistent with the only previous, smaller study that compared these two techniques in which Byhahn et al. demonstrated one TRF with the PercuTwist and none with the Blue Rhino, and both groups contained 35 patients.
In conclusion, though the numbers are small, we believe these results suggest that TRF does not appear to increase the incidence of tracheal stenosis. This may have been related to the fact that both PDT techniques were performed under direct visualization using an endoscope and that there were no high placements of the tracheostomy.
This study was presented in part at ESICM, Barcelona, 2006.
1 Ciaglia P, Graniero KD. Percutaneous dilatational tracheostomy; results and long-term follow-up. Chest 1992; 101:464–467.
2 Marz WA, Ciaglia P, Graniero KD. Some important details in the technique of percutaneous dilatational tracheostomy via the modified Seldinger technique. Chest 1996; 110:762–766.
3 Van Heurn LW, Theunissen PH, Ramsey G, Brink PR. Pathological changes of the trachea after percutaneous dilatational tracheostomy. Chest 1996; 109:1466–1469.
4 Norwood S, Vallina VL, Short K, et al
. Incidence of tracheal stenosis and other late complications after percutaneous tracheostomy. Ann Surg 2000; 232:233–241.
5 Grundling M, Kuhn SO, Nees J, et al
. Percutwist dilatational tracheostomy. Prospective evaluation of 54 consecutive patients. Anaesthesist 2004; 53:434–440.
6 Frova G, Quintel M. A new simple method for percutaneous tracheostomy: controlled rotational dilation. Int Care Med 2002; 28:299–303.
7 Scherrer E, Tual L, Dhonneur G. Tracheal ring fracture during a Percutwist tracheostomy procedure. Anesth Analg 2004; 98:1451–1453.
8 Kinnear J, Higgins D. Tracheal ring fracture and herniation with PercuTwist percutaneous dilator. Intensive Care Med 2004; 30:1242–1243.
9 Walz MK, Schmidt U. Tracheal lesion caused by percutaneous dilatational tracheostomy – a clinico-pathological study. Intensive Care Med 1999; 25:102–105.
10 Chin Ho E, Kapila A, Colquhoun-Flannery W. Tracheal ring fracture and early tracheomalacia following percutaneous dilatational tracheostomy. BMC Ear
Nose Throat Disord 2005; 5:6.
11 Raghuraman G, Rajan S, Marzouk JK, et al
. Is tracheal stenosis caused by percutaneous tracheostomy different from that by surgical tracheostomy. Chest 2005; 127:879–885.
12 Cobean R, Beals M, Moss C, Bredenberg CE. Percutaneous dilatational tracheostomy. A safe, cost-effective bedside procedure. Arch Surg 1996; 131:265–271.
13 Byhahn C, Westphal K, Meininger D, et al
. Single-dilator percutaneous tracheostomy: a comparison of Percutwist and Ciaglia Blue Rhino techniques. Intensive Care Med 2002; 28:1262–1266.