The clinical use of right-sided double-lumen tubes

Abstract

Right-sided double-lumen tubes (DLTs) have a bad reputation. Many experts in the field of thoracic anesthesia regard them as being difficult to position, having a small margin of safety for correct placement, and being prone to intraoperative malpositioning. However, in a randomized prospective study, Campos et al. compared the use of right vs left DLTs in two groups of 20 patients having left thoracotomies. In this small study, there were no significant differences between the two types of DLTs with respect to the relevant aspects of clinical performance, including the time for left lung collapse and the incidence of inadvertent right upper lobe collapse. There was a tendency for rightsided tubes to become malpositioned intraoperatively, but in all cases this difficulty was corrected easily by fibreoptic bronchoscopy. In a more recent retrospective report, the anesthetic records of 961 thoracic procedures were examined at one teaching institution where the usual practice was to use a DLT contralateral to the side of surgery, i.e., a rightsided tube for left-sided surgery. There were no differences in the incidences of hypoxemia, hypercarbia, or high airway pressures between patients managed with left or right DLTs. The current sales of DLTs in North America show a 10:1 preference for leftvs right-sided tubes (personal communication with Covidien, Mansfield, MA, USA), suggesting that the majority of anesthesiologists tend to use left DLTs whenever possible. Given the evidence that right DLTs may function as well as left DLTs, and in view of the fact that it is necessary to use a right DLT in certain select cases, perhaps it is time to reconsider their use for routine airway management in thoracic surgery. To appreciate our current clinical practice in thoracic anesthesia, it is useful to understand how we arrived at where we are today. Both the spectrum of patients and the equipment available for lung isolation have changed drastically from the origins of lung isolation in the 1930s. At that time, thoracic surgery was essentially for complications of infectious diseases, e.g., abscesses, bronchiectasis, hemoptysis, etc., which were often due to tuberculosis. The anesthesiologist’s major priority was to protect the dependent lung from contamination with the infected secretions from the operative lung. The initial methods of lung isolation involved placement of a modified endotracheal tube as a single-lumen endobronchial tube in the mainstem bronchus of the non-operative lung. These tubes were placed by a rigid bronchoscope through the singlelumen tube and rigid bronchoscopy was a standard skill of the pioneers of thoracic anesthesia. Selective intubation of the contralateral lung became an established principle. In 1949, Carlens, a respirologist, introduced a red rubber leftsided DLT designed to be placed with topical anesthesia in awake patients with tuberculosis who were having splitlung broncho-spirometry as a part of their workup for possible lung resection. This DLT was quickly adopted by the thoracic surgeon, Bjork, who published a report with Carlens regarding the DLT’s use in 500 pulmonary resections in 1952. This landmark DLT had a carinal hook so it could be positioned solely with laryngoscopy and auscultation, eliminating the need for rigid bronchoscopy. It allowed simultaneous ventilation of the dependent lung and suctioning of the non-dependent lung, and it became the preferred device for lung isolation in the 1950’s in preference to single-lumen tubes and bronchial blockers. Thus began the clinical preference for left DLTs. A right-sided version P. Slinger, MD (&) Department of Anesthesia, Toronto General Hospital, University of Toronto, Eaton North Wing, 3rd Floor, Room 441, 200 Elizabeth Street, Toronto, Ontario M5G 2C4, Canada e-mail: peter.slinger@uhn.on.ca