eComment: Objective quantification of airleaks after resectional lung surgery Free

I read with interest the article by Korasidis et al. regarding the management of air leak and residual air spaces after resectional lung surgery [1].

The quantification system used by the authors seems very arbitrary. The different shapes and the sizes of the bubbles render the counting system far from being perfect for quantifying air leaks and looks rather primitive. Further, it was not conveyed in the article whether the air leak measured was during normal respiration, at rest, or was it the maximum air leak during forced expiration. Without such quantification the question whether some of the air leaks would have ceased without intervention remains unanswered. Furthermore, the article does not mention how many patients had mild, moderate or severe leaks, a parameter which would have a definitive bearing on the scope of the therapeutic modality.

Air leaks have been graded as I – forced expiratory only, II – expiratory only, III – inspiratory only, or IV – continuous, and it it has been observed that if an air leak does not stop by postoperative day 4 it will probably persist until postoperative day 7, and may need intervention [2].

Alternatively an air leak meter, which is housed within the drainage system (Sahara S-1100 Pleur-evac chest drainage system – Genzyme Biosurgical, Cambridge, MA, USA), can be used. The size of the air leak is graded from 1 (the smallest) to 7 (the largest). The graded air leak is then used as a guide for the initiation and assessment of the utility of various interventions [3].

Alternatively an electronic measuring device – digital group (electronic measure of pleural air leak using Millicore AB DigiVent^™ chest drainage system) can be used. It indicates actual airflow, records air leaks over time, shows true pressure levels, and displays the pressure variations with respiration, the ‘swing’. The device has been claimed as being easy to use [4]. While I concede that the expensive digital systems may not be affordable in the day-to-day practice, in today’s economy in medicine, scientific trials do need objective quantification for sensitivity and specificity of various intervention modalities.

The article also has some inconsistencies in reporting. In the text, it is mentioned that air leaks stopped in all patients at 144 h but in the algorithm the time of chest tube removal is mentioned as 120 h. Does that mean that the chest tubes were removed before the air leak had stopped? And if that is the case, how was the leak detected at all? At another place the authors mentioned that all the leaks stopped at 144 h (6 days) – in this instance why then were some patients sent home with Heimlich valves?

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