IPSILATERAL PNEUMOTHORAX DURING ONE-LUNG VENTILATION - A RARE, SUPPOSEDLY TYPICAL COMPLICATION IN THE USE OF DOUBLE-LUMEN TUBES

The authors report a rare, recently diagnosed and atypical mishap duri ng one-lung ventilation (OLV) via a double lumen tube (DLT) and left-s ided thoracotomy: an ipsilateral pneumothorax during ventilation of th e right lung. This occurred in a 63-year-old patient with chronic obst ructive airway disease who was scheduled for urgent repair of a descen ding thoracic aortic aneurysm. Anaesthesia and surgery were uneventful until aortic cross-clamping release. The common presentation of incre ased intrathoracic extrapleural pressure owing to a pneumothorax in pa tients with mechanically ventilated lungs is a rapid decrease in oxyge n saturation, followed or paralleled by haemodynamic deterioration. Al though the above presentation could be seen in this case, the diagnosi s of a tension pneumothorax was delayed twice. First, symptoms were in itially obscured by haemodynamic changes resulting from a head-down ti lt and aortic declamping. Second, since the lack of consolidation afte r aortic declamping focused attention on the airway problems, complica tions resulting from the use of a DLT were primarily considered. In pa rticular, since breathing sounds were detectable initially, malpositio n or torsion of the DLT had to be excluded by fibre-optic bronchoscopy , which involved a further delay. Finally, two observations led to the diagnosis of a right-sided tension pneumothorax: (1) bullae of the co ntralateral lung, detected during thoracotomy; (2) the finding that ve ntilation of both lungs and the left lung subsequently increased arter ial (SaO2) and mixed venous oxygen saturation (SvO2) and the circulato ry status, but ventilation of the right lung caused a deterioration. C hest radiography and insertion of a chest tube with drainage of air, t hereafter, validated our hypothesis. The time course of oxygen desatur ation during OLV and tension pneumothorax was as severe as expected; t he time course of haemodynamic deterioration, however, appeared quicke r and had more impact than expected. Assuming that mediastinal deviati on was not hindered by contralateral intrathoracic pressure during tho racotomy, we believed that circulation should be depressed later or to a lesser extent in patients with an intraoperative pneumothorax. Yet, during thoracotomy, decrease in cardiac filling and output during ten sion pneumothorax in OLV obviously results primarily from the immovabi lity of the mediastinum owing to mediastinal fixation and is at least as decisive as the contralateral intrathoracic pressure in closed-ches t patients. In summary, a tension pneumothorax during one-lung ventila tion and thoracotomy is a rare, but disastrous complication during the use of a DLT, which has not, to our knowledge, been reported previous ly. We recommend that tension pneumothorax be added to the list of com plications and problems during OLV by the use of a DLT, especially in patients with structural lung diseases.