A Clinical Comparison of Two New Bronchial Blockers vs. Double Lumen Tubes in One Lung Ventilation

STUDY END POINTS The time required to achieve lung separation, from beginning of laryngoscopy to lung isolation (inflation of the bronchial cuff or blocker), will be recorded. The thoracic surgeons, using a verbal analogue scale, will assess the lung collapse(lung collapse scores-LCS, 0=no collapse, to 10=complete collapse). The LCS will be assessed and recorded as they open the pleura during the procedure (LCS 0), and at 10 min., (LCS 10), and 20 min. (LCS 20) after opening the pleura. The surgeons will be blinded to the lung isolation device used in the patient. If the lung collapse is not satisfactory, the FOB will be passed to assess the lung isolation, and if necessary reposition the device. A malposition will be defined as a clinically obvious relocation of the devise in the trachea or bronchus and a loss of lung isolation interfering with surgery. The number of repositions of the lung isolation device after initial supine placement, airway pressures, tidal volumes, duration of surgery, and the arterial blood gases 20 minutes after pleural opening will be noted.

In addition to the primary end points of time to lung isolation and number of required repositioning maneuvers, the following variables will be recorded: Age, gender, weight, height, BMI, ASA, airway Mallampati score, pulmonary spirometry (if clinically performed: TLC, FEV1, FVC, DLCO), LCS 0/10/20, ventilatory parameters on OLV (airway pressure, tidal volume, respiratory rate, compliance, duration of OLV and surgery, arterial blood gas 20 minutes after opening the pleura (pH, paO2, pCO2 bicarbonate, base excess, oxygen saturation), and finally the dimensions of the left main bronchus (LMB) and the right main bronchus (RMB) using the on-screen program of the radiology server on the pre-operative chest imaging, by the anesthesiologist.

Inclusion criteria

• Age >18 years.
• Thoracic surgery requiring one-lung ventilation for > 30 minutes.
• Able to provide first party consent.

Exclusion criteria

• Known prior difficult intubation.
• Upper airway exam suggestive of difficult intubation.
• Surgical procedure requiring a right double lumen endotracheal tube (such as left pneumonectomy).
• Evidence on clinically required radiologic imaging of abnormal lower airway anatomy, such as right upper lobe origin of the bronchus.
• Prior thoracic surgery or pleurodesis of the operative side (would delay lung collapse).
• History of severe restrictive lung disease (such as pulmonary fibrosis or emphysema) which may affect inflation/deflation times.
• Trauma patients requiring video-assisted thoracoscopic surgery
• Has condition(s) that contraindicate a double lumen endotracheal tube (DLT) or the placement of a bronchial blocker (BB) via a single lumen endotracheal tube.
• Patients with communication difficulties.