Incidence of malposition of polyvinylchloride and red rubber left-sided double-lumen tubes and clinical sequelae

Dimensional Variations of Left-Sided Double-Lumen Endobronchial Tubes

Background

Tube size selection is critical in ventilating patients' lungs using double-lumen endobronchial tubes (DLTs). Little information about relevant parameters is readily available from manufacturers. The aim of this study is to provide reference data for relevant dimensions of conventionally available DLTs.

Methods

In this study in a benchmark in vitro setup, several dimensional parameters of four sizes of left-sided double-lumen endobronchial tubes from six different manufacturers were assessed, such as distances and diameters of tube shaft, cuff lengths, and diameters as well the angle at the tip.

Results

Endobronchial tubes of ostensibly the same size revealed wide variation in measured parameters between brands from different manufacturers. In some parameters, there was an overlap between different sizes from the same manufacturer, i.e., diameters and distances did not increase with increasing nominal endobronchial tube size. The information about dimensions of endobronchial tubes provided by manufacturers' leaflets is insufficient.

Conclusions

Endobronchial tube size selection carries unnecessary uncertainty because clinically relevant parameters are unknown and vary considerably between different manufacturers.

A simple blind placement of the left-sided double-lumen tubes

One-lung ventilation (OLV) has been commonly provided by using a double-lumen tube (DLT). Previous reports have indicated the high incidence of inappropriate DLT positioning in conventional maneuvers.After obtaining approval from the medical ethics committee of First Affiliated Hospital of Anhui Medical University and written consent from patients, 88 adult patients belonging to American society of anesthesiologists (ASA) physical status grade I or II, and undergoing elective thoracic surgery requiring a left-side DLT for OLV were enrolled in this prospective, single-blind, randomized controlled study. Patients were randomly allocated to 1 of 2 groups: simple maneuver group or conventional maneuver group. The simple maneuver is a method that relies on partially inflating the bronchial balloon and recreating the effect of a carinal hook on the DLTs to give an idea of orientation and depth. After the induction of anesthesia the patients were intubated with a left-sided Robertshaw DLT using one of the 2 intubation techniques. After intubation of each DLT, an anesthesiologist used flexible bronchoscopy to evaluate the patient while the patient lay in a supine position. The number of optimal position and the time required to place DLT in correct position were recorded.Time for the intubation of DLT took 100 ± 16.2 seconds (mean ± SD) in simple maneuver group and 95.1 ± 20.8 seconds in conventional maneuver group. The difference was not statistically significant (P = 0.221). Time for fiberoptic bronchoscope (FOB) took 22 ± 4.8 seconds in simple maneuver group and was statistically faster than that in conventional maneuver group (43.6 ± 23.7 seconds, P < 0.001). Nearly 98% of the 44 intubations in simple maneuver group were considered as in optimal position while only 52% of the 44 intubations in conventional maneuver group were in optimal position, and the difference was statistically significant (P < 0.001).This simple maneuver is more rapid and more accurate to position left-sided DLTs, it may be substituted for FOB during positioning of a left-sided DLT in condition that FOB is unavailable or inapplicable.

One-Lung Anesthesia Update

One-lung ventilation is used during a variety of cardiac, thoracic, and major vascular procedures. Endobronchial tubes, bronchial blockers, and occasionally, single-lumen tubes are used to isolate the lungs. Patients with difficult airways and pediatric patients provide special challenges for lung isolation. Finally, intraoperative hypoxia and hypercarbia in patients with intrinsic lung disease frequently complicate one-lung anesthesia. The concepts and controversies in lung isolation techniques are discussed.

Double-lumen tube position should be confirmed by fiberoptic bronchoscopy

PURPOSE OF REVIEW

This review is part of Pro and Contra use of fiberoptic bronchoscopy to confirm the position of a double lumen tube. The purpose of this review is to highlight the circumstances where fiberoptic bronchoscopy should be used in conjunction with lung separation, right sided double-lumen tube positioning, and to identify fine malposition for generally missed by clinical signs.

RECENT FINDINGS

Until several years ago, confirmation of a double-lumen tube (DLT) position was limited to inspection and auscultation. Fiberoptic bronchoscopes were usually only available in the bronchoscope suite for the exclusive use of the pulmonary personnel. Today, in most institutions, fiberoptic bronchoscopes of different diameters are available in the operating room for use by the anesthesia personnel.

SUMMARY

Advances in technology and improved quality of the endoscopes image make the technique easy to use with a relatively simple learning curve. In fact, fiberoptic workshops, thoracic workshops and difficult airway workshops are offered in nearly all important anesthesia meetings.

Fiberoptic bronchoscopy need not be a routine part of double-lumen tube placement

PURPOSE OF REVIEW

The debate continues as to whether a fiberoptic bronchoscope must be used to position a double-lumen tube. This review supports the argument that although bronchoscopy is extremely helpful, it is not always needed for the routine placement of left double-lumen tubes.

RECENT FINDINGS

Several recent clinical reports have demonstrated that an experienced anesthesiologist can safely and consistently position double-lumen tubes without bronchoscopic assistance. In order to do so several important factors must be considered. These include the appropriate choice of tube (left or right), size of tube, and endpoint for the depth of insertion.

SUMMARY

Although bronchoscopy is useful, no double-lumen tube positioning method is fail-safe. The choice of which approach to use, 'blind' versus fiberoptic bronchoscope-assisted, is influenced by many factors. Operator experience with any method increases the likelihood of success. A fiberoptic bronchoscope is not always needed for left double-lumen tube placement.

Methods of lung separation

In the last few years, video assisted thoracoscopy, which allows a wide variety of diagnostic and therapeutic procedures, has been introduced into clinical practice. A growing enthusiasm for minimally invasive surgical approaches and improvements in video endoscopic surgical equipment has resulted in the widespread use of this technique. Most video assisted thoracoscopy procedures require a well-collapsed lung and should only be included in the absolute indication for one-lung ventilation. Following placement of a double lumen tube, it is the standard of care to check the tube is positioned correctly using fiberoptic bronchoscopy. The role of the right-sided double lumen tube is discussed in detail in this review. Finally, there are alternatives to the use of the double-lumen tube to achieve lung separation, such as the Univent tube or an independent bronchial blocker. In many situations the double-lumen tube cannot be inserted, due to a difficult airway or at the conclusion of the procedure changing the double lumen tube to a single lumen tube may result in loss of control over the airway. In such situations, it is essential for the anesthesiologists to be familiar with the existing alternatives to the double-lumen tube.

Management of one-lung ventilation

The practice of thoracic anesthesia requires a clear understanding of the techniques of lung separation and the technical skills necessary to apply such techniques. Customarily they are classified as absolute or relative.

The effects of endobronchial cuff inflation on double-lumen endobronchial tube movement after lateral decubitus positioning

OBJECT

This study was designed to measure changes in tracheal and bronchial lumen distances from mainstem and secondary carina with lateral positioning, and to assess whether inflation of the endobronchial cuff before lateral positioning would further secure a double-lumen endobronchial tube (DLT) and reduce movement.

DESIGN

Prospective study.

SETTING

University-affiliated cancer center.

PARTICIPANTS

Fifty adult patients scheduled for elective thoracic surgical procedures requiring the placement of a left DLT.

INTERVENTIONS

Patients were sequentially assigned to either the endobronchial cuff-inflated group or the deflated group during lateral positioning. After induction of general anesthesia, a left polyvinylchloride (PVC) DLT was placed and the position confirmed. In the supine position, the distance from the tip of the tracheal lumen to main carina was measured using a fiberoptic bronchoscope (FOB) passed through the tracheal lumen, and the distance from the bronchial lumen to secondary carina was measured with the FOB passed through the bronchial lumen. The patients were then positioned laterally and a second set of measurements taken. Overall movement was determined by increases and decreases in tracheal and bronchial distances obtained by substracting supine values from lateral values.

MEASUREMENTS AND MAIN RESULTS

There was significant tracheal movement in 40 of 50 patients, with a mean of 0.92 +/- 1.0 cm. This was predominantly in the upward direction, as seen in 35 of 50 patients. There was significant bronchial movement in 37 of 50 patients, with a mean of 0.92 +/- 1.15 cm. Also, predominance in the upward direction was seen in 34 of 50 patients.

CONCLUSIONS

DLTs move with lateral positioning, regardless of endobronchial cuff inflation. The movement is predominantly in the upward direction. Therefore, fiberoptic visualization in the supine position should be used only to confirm that the endobronchial lumen is placed on the appropriate side and the cuff is at least 1 cm inside the left mainstem bronchus. Final positioning should always be verified in the lateral position.