Clinical Trial: Techniques for Lung Deflation With Arndt® Blocker

Study Status: Completed
Recruit Status: Completed
Study Type: Interventional

Official Title: Lung Deflation With Arndt® Blocker During Video-Assisted Thoracoscopy: A Comparison of the Disconnection Technique With a Continuous Bronchial Suction

Brief Summary:

The use of wire-guided Arndt® endobronchial blocker does not gain widespread acceptance during video-assisted thoracoscopy (VATS) because it takes longer time to collapse the operative lung especially in patients with chronic obstructive lung disease (COPD). The use of a disconnection technique for deflation of Arndt® blocker had a comparable degree of lung collapse with the use of double-lumen tubes. However, it carries a risk of blood or infected secretions contaminating the dependent lung.

We hypothesise that the use bronchial suction of through a barrel part of a 1-mL insulin syringe attached to the suction port of the bronchial blocker would be associated with comparable time to optimum lung collapse with the disconnection technique.

After ethical approval, 58 patients with spontaneous pneumothorax scheduled for elective VATS using Arndt blocker® for lung separation will be included in this prospective, randomized, double-blind study.

Patients will be randomly assigned to deflate the blocker with either disconnecting the endotracheal tube from the ventilator for 60 s. prior to inflation of the bronchial blocker allowing both lungs to collapse, or attaching -20 cm H2O of suction to the suction port of the blocker through the barrel part of a 1-mL insulin syringe (n = 29 for each group).

Detailed Summary:

Most Middle Eastern and British thoracic anesthesiologists (100% and 98%, respectively) are using a double-lumen endobronchial tube (DLT) as the first-choice lung separation technique, 1-2 although the intubation with a single lumen tube (SLT) could be easier. However, the use of a bronchial blocker has a special concern as it takes longer time to collapse the operative lung,3 which precludes its widespread acceptance for video-assisted thoracoscopic (VATS) procedures because of delayed insertion of the trocars.

The wire-guided Arndt® endobronchial blocker (Cook® Critical Care, Bloomington, IN) takes longer time for lung collapse than the Univent® tube (approximately, 26 min vs. 19 min, respectively; P<0.006),3 that may be due to its narrower inner lumen (1.4 mm vs. 2.0 mm, respectively).

There are different techniques described to speed of lung collapse during the use of Arndt® endobronchial blocker. These include the disconnecting of the SLT from the ventilator and allowing both lungs to collapse before inflation of the bronchial blocker cuff, 4-5 or bronchial suction either through the fiberoptic bronchoscope after deflation of the bronchial cuff and cessation of ventilation before re-inflation of the bronchial cuff, or through a barrel part of a 3-mL syringe attached to the suction port of the bronchial blocker.3 The use of a modified disconnection technique for deflation of Arndt® endobronchial blocker had a comparable degree of lung collapse with the use of DLT during VATS procedures in patients presented with pneumothorax.5 However, compared with the bronchial suction, the disconnection technique may carry a risk of blood or infected secretions contaminating the dependent lung.6

To the best of our knowledge, the comparison of the efficacy
Sponsor: Dammam University

Current Primary Outcome: time needed for lung collapse [ Time Frame: 3 min before one lung ventilation ]

Original Primary Outcome: Same as current

Current Secondary Outcome:

• quality of lung collapse [ Time Frame: every 20 min intervals after one lung ventilation initiation ]
  The quality of lung collapse at 20 min intervals after one lung ventilation initiation according to a four-point ordinal scale,3, 8 ranging from 1 (extremely poor) to 4 (excellent). Extremely poor (Score 1) indicated no collapse; poor (Score 2) indicated that there is a partial collapse with interference with surgical exposure; good (Score 3) indicated that there is total collapse, but the lung still had residual air; and excellent (Score 4) indicated a complete collapse with perfect surgical exposure. The feasibility of this scale was investigated during six surgical procedures not included in the study.
• Overall surgeon satisfaction [ Time Frame: 15 min after surgery ]
  Overall surgeon satisfaction with surgical conditions as assessed using a verbal analog scale (0 = unsatisfied to 10 = very satisfied)
• Number of times that the fiberoptic bronchoscope required to assure proper position [ Time Frame: 5 min after reinflation of the surgical lung ]
  The number of times that the FOB was required to assure proper position or to perform further bronchial suction
• Intraoperative hypoxemia [ Time Frame: For 2 hours during surgery ]
  Intraoperative hypoxemia (SaO2 < 92%)

Original Secondary Outcome:

• quality of lung collapse [ Time Frame: every 30 min intervals after one lung ventilation initiation ]
  The quality of lung collapse at 30 min intervals after one lung ventilation initiation according to a four-point ordinal scale,3, 8 ranging from 1 (extremely poor) to 4 (excellent). Extremely poor (Score 1) indicated no collapse; poor (Score 2) indicated that there is a partial collapse with interference with surgical exposure; good (Score 3) indicated that there is total collapse, but the lung still had residual air; and excellent (Score 4) indicated a complete collapse with perfect surgical exposure. The feasibility of this scale was investigated during six surgical procedures not included in the study.
• Overall surgeon satisfaction [ Time Frame: 15 min after surgery ]
  Overall surgeon satisfaction with surgical conditions as assessed using a verbal analog scale (0 = unsatisfied to 10 = very satisfied)
• Number of times that the fiberoptic bronchoscope required to assure proper position [ Time Frame: 5 min after reinflation of the surgical lung ]
  The number of times that the FOB was required to assure proper position or to perform further bronchial suction
• Intraoperative hypoxemia [ Time Frame: For 2 hours during surgery ]
  Intraoperative hypoxemia (SaO2 < 92%)

Dates:
Date Received: January 7, 2014
Date Started: January 2014
Date Completion:
Last Updated: April 3, 2015
Last Verified: April 2015