Reply to the Letter to the Editor Reply to Hunt

of VATS lobectomy compared to thoracotomy lobectomy and the influence of the length of stay very much mirror our own larger experience in Canada. When we compared costs of over 250 VATS lobectomy cases to an open lobectomy, intraoperative costs were approximately double ($2810CD vs $1425CD). However, length of stay (LOS) was 1.3 days shorter for VATS cases (4.9 days vs 6.2 days). Based on an analysis of overall costs, a VATS lobectomy was equal or slightly less than an open lobectomy ($8573CD vs $8673CD). The similarity between the costs from our experience and that of Mr Walker’s group is striking. An additional influence on intra-operative cost and potential impact on LOS is the need to convert a VATS to an open lobectomy. No mention was made of this, though elsewhere the group has reported conversion rates of around 10% [2]. In our analysis, conversion rates over the 3-year period were 13% (35 cases converted). We have examined the causes of conversion in our unit and proposed a method of auditing this (presented recently as an abstract at the Society of American Gastrointestinal and Endoscopic Surgeons (SAGES) 2009 meeting). Clearly, the timing and cause of conversion during surgery will have some influence on the intra-operative costs incurred, but, overall, converting a VATS lobectomy to a thoracotomy had little impact on total intra-operative costs ($2861CD no conversion vs $2569CD converted). The difference between LOS on patients who had been converted was half a day (4.9 days no conversion vs 5.4 days converted). Majority of the patients were converted through an extension of the axillary utility incision with only a few patients requiring a separate posterolateral thoracotomy. This translated into a difference in LOS costs of $610CD ($5669CD no conversion vs $6279CD converted). Overall the difference in costs incurred following conversion was $303CD ($8546CD no conversion vs $8849CD conversion). Conversion through the axillary incision appears to have a small adverse influence on increased LOS and overall impact on cost was low. Our experience will be presented this summer at the 13th World Conference on Lung Cancer, and we welcome Mr Walker’s perspective on the influence of conversion rates on the costs incurred.