Know Your Equipment: One-lung Ventilation endobronchial tubes that had two cuffs: a tracheal and a bronchial. This was passed into the bronchus using a rigid bronchoscope. When only the tracheal cuff was inflated both the lungs could be ventilated, but when the bronchial one was inflated, only that lung was ventilated, thus isolating the other one. The MacintoshLeatherdale, Green-Gordon and Brompton-Pallister are examples of such double-cuffed endobronchial tubes. These tubes had a small tube incorporated within them that could be used for suction from or oxygenation to the operated lung. [1,2,3,4] During the initial years of thoracic surgery, the patient was positioned such that the operative side was dependent to avoid soiling of the healthy lung, but this made the surgical approach difficult. A DLT has made surgical access easier.
Verghese T. Cherian, MD, FFARCSI
Indications for OLV The indications for OLV have expanded beyond its traditional one for lung resection surgery. It is used to provide ease in access during surgery on the esophagus, the aorta, or the thoracic spine. It provides invaluable operating conditions during minimally invasive video-assisted thoracoscopy surgery (VATS).
Professor of Anesthesiology Penn State Health College of Medicine Hershey, PA 17033 mailto:vcherian@pennstatehealth.psu.edu Introduction & Historical perspective Thoracic surgery poses 3 main challenges
Figure 1: Pulmonary physiology with change in position
a. T horacotomy collapses the lung and makes spontaneous breathing ineffective. b. The ventilatory movements of the lung makes surgery difficult. c. The blood, pus and debris from the diseased lung may spill over to the healthy lung. The first can be rectified by positive pressure ventilation, while the other two need isolation of the operative lung and ventilation of the non-operative lung. Although, a double lumen tube (DLT) seems to be the preferred technique for one lung ventilation (OLV), the first described lung isolation for resection of a diseased lung was achieved by passing the standard endotracheal tube (ETT) further into the bronchus of the healthy lung, by Gale, in 1931. In 1935, Archibald inserted a rubber catheter with an inflatable distal balloon into the bronchus of the lung to be operated, while ventilating the healthy lung through an ETT inserted alongside the blocker catheter. [1] Perhaps the precursor to the DLT were the single lumen
Physiology of one-lung ventilation To understand the implication of one-lung ventilation, it is essential to know how the ventilation and the perfusion through the lung changes from an upright to a lateral decubitus position and then when a pneumothorax is created. The ventilation (V), perfusion (Q), and V/Q ratio differs between the regions of the lung and is altered with the position of the subject. Figure 1 shows the continued on page 12
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