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Abstract

We thank Drs Morgan and Roberts for their interest in our study. Dealing with the points raised sequentially: We carefully registered all the problems we encountered, even those problems that were easily overcome. We defined major complications as those requiring surgical or medical intervention. Posterior wall puncture, seen at bronchoscopy, in this context constitutes a minor event. The use of bronchoscopy creates a direct view of the posterior tracheal wall. In cases of imminent puncture of the posterior tracheal wall, puncture can be avoided. This is the main reason why we routinely advocate bronchoscopy [1]. We choose to speak of ‘puncture’ and not of ‘perforation’, which can be devastating [2]. It is important to note that this would remain unrecognised without performing bronchoscopy. Pneumothorax only can happen if the puncture is off the midline and perforates the posterior tracheal wall. Understandably, we always take precautions to avoid accidental extubation, but it is only a real problem in cases of difficult intubation. The two patients where accidental extubation has happened were easily re-intubated. The only case where subcutaneous emphysema was impressive was related to the use of a fenestrated tube [3]. With appropriate measures, the emphysema disappeared within several hours, so we decided to define this as an annoying, but minor, complication because there were no residual problems for the patient. Difficulties in introducing the cannula were encountered twice and were related to the transition from obturator to cannula-tip. As discussed, the diameter of a Shiley-cannula is relatively large, making introduction sometimes difficult, but not impossible. Puncture of the tracheal tube is a well known problem, which is diagnosed easily by rotating and oscillating the tube to ensure that the needle has not impaled the tube. In our opinion, it does not constitute a major problem either. We agree that this is usually not very important and is influenced, for example, by the procedure being performed by less experienced colleagues under supervision, as is often the case in a teaching hospital like ours. But sometimes the duration of the procedure, and particularly the time that the patient is not adequately ventilated, may be critical in patients with severe respiratory difficulties. Also in emergency situations, percutaneous techniques may be used [4, 5]. In those circumstances, the fastest procedure may be desirable [6]. Therefore, timing of the procedure was and is of interest. This is not always necessary. However, the use of the Crile's forceps was in many cases clinically important. We always perform blunt dissection in the midline, avoiding blood vessels lying more laterally. Identification of the trachea, by digital palpation, was a lot easier, so the puncture was easier and the time of compromised ventilation was therefore shorter than before the use of the Crile's forceps. Many other authors using the multiple dilators technique, and even Ciagla in his original paper, advocate the use of some blunt dissection and so do several authors using the Blue Rhino technique [7-10]. We appreciate the good wishes of Drs Morgan and Roberts, but we want to stress that the meticulous way we prospectively registered our peri-operative complications makes our survey difficult to compare with registrations not done in the context of research.