Endobronchial EZ-Blocker Compared to Left Sided Double-Lumen Tube for One-Lung Ventilation

Lung isolation is used to achieve one lung ventilation to facilitate thoracic
surgery. Two methods are commonly used, a double lumen tube (DLT) or a
bronchial blocker introduced through a single lumen tube. However, both
techniques have advantages and disadvantages. Briefly, the DLT can be
positioned faster and remains firmly in place, but is sometimes difficult or
even impossible to introduce. The DLT is larger than a conventional single
lumen tube and the incidence of postoperative hoarseness and airway injuries is
higher. Compared to the DLT, bronchial blocking devices are more difficult to
position and need more frequent intraoperative repositioning. These
disadvantages of the existing devices for lung isolation prompted further
development of the bronchial blocker concept. The design of a new Y shaped
bronchial blocker, the EZ- Blocker® (AnaesthetIQ BV, Rotterdam, The
Netherlands) (EZB), combines the advantages of both lung isolation techniques.
The EZB has been evaluated in a porcine model, a mannequin, in a human corpse
and in a clinical study. The EZB blocker is recently CE certified. There is
not yet a clinical study that evaluates the efficacy and safety of the device.

The aim of the study is to compare the ease of placement, the incidence of
malpositioning and the quality of lung deflation of a left DLT and a EZB.
Secondly, the incidence and severity of damage to laryngeal, tracheal and
bronchial structures caused by the use of the DLT or the EZB is a target of the
study.

The study is randomized, prospective and partially blinded.

The surgeon is blinded to the technique used when he has to give his opinion on
the quality of the lung deflation. The lung specialist is blinded when he/she
reviews the video*s of bronchi, trachea and larynx. The patient and the
interrogator is blinded when he/she is interviewed for sore throat and
hoarseness.

The study takes place at the Radboud University Nijmegen Medical Centre.
Probably the study will start in the beginning of 2010 and it will end one year
later.
Patients are recruited during their pre-operative assessment one week before
their operation. Patients are randomized into two groups using a computer
generated code prepared by a statistician.

The patients are treated equally regarding pre-operative preparations and per-
and post-operative treatment, except the placement of the device for lung
isolation. The placement of a double lumen tube is the standard clinical
practice. Inspection by fiber optic bronchoscopy of the position of the device
is routine. A check for injury caused by the device to the patient*s larynx,
trachea or bronchus is often performed during final inspection of patient*s
airway (e.g. suture inspection, removal of blood or secretions in the airway).
The available hospital protocols (KWINT) are used for the preoperative
assessment and per- and post- operative treatment. The study is performed by
four anesthesiologists experienced with both techniques (wide experience with
DLT and at least 5 placements of the EZ-blocker).

Traditionally, single lung ventilation is obtained with a double lumen tube
(DLT). In our institution a polyvinyl DLT (Broncho-cath, Mallinckrodt,) without
carinal hook, is used. This type of tube exists of a tube with two lumen with
two distal cuffs. One lumen (called the bronchial lumen) extends some distance
further, has a slight curvature and has a small blue cuff. The other lumen
(called the tracheal lumen) has a larger cuff. A DLT tube exists in four sizes
and one can choose in a left or a right configuration. Almost always,we use a
left sided DLT. A DLT has a much larger diameter than a standard single lumen
endotracheal tube.

The EZ-blocker (EZB) is a semi-rigid catheter with two distal extensions, both
with an inflatable cuff and a central lumen. It is intended for use in
combination with a single lumen tube. After the EZB is advanced trough the
distal end of the single lumen tube, both extensions spread out and find their
way in the left and right main stem bronchi. The place where the two extensions
are attached to the shaft now rests on the carina. Fiberoptic bronchoscopy
should be used for proper positioning. After placement of the EZB, one of the
cuffs can be inflated to obtain lung separation under direct visual inspection
with fiberoptic bronchoscopy.

If placement of a DLT is unsuccesful it will be replaced by an EZB and if
placement of an EZB is unsuccesful it will be replaced by an EZB.

Patients are under anaesthesia when one of the devices for lung isolation are
placed. Participation in the study does not result in additional risks for the
patient. There are no direct benefits for the participating patients.