Improving the design and function of double-lumen tubes

Comparison of the accuracy of three methods measured the length of the right main stem bronchus by chest computed tomography as a guide to the use of right sided double-lumen tube

BACKGROUND

The variation of right main stem bronchus leads to the orifice of the right upper lobe bronchus may be obstructed or increase the incidence of malposition intraoperatively when the right sided double-lumen tube is used. Therefore, the aim of this study was to compare the accuracy of three methods measured the length of the right main stem bronchus via chest computed tomography as a guide to the use of right sided double-lumen tube.

METHODS

In this study, 168 adult patients undergoing left sided thoracic surgery were included. All these patients were allocated to carina-proximal (C-P) group, carina-distal (C-D) group and carina-carina (C-C) group. The position of endobronchial cuff observed via Fiberoptic bronchoscopy after successful initial placement and after turning the patients to the lateral decubitus position, as well as the incidence of malposition of right sided double-lumen tube intraoperative were recorded to assess the accuracy of three methods in predicting the position of right sided double-lumen tube.

RESULTS

The distance between the carina to the proximal margin of the right upper lobe orifice, carina to the distal margin of the right upper lobe orifice and carina to the first right interlobar carina of the right upper lobe orifice were 17.2 ± 2.3 mm, 25.4 ± 3.7 mm and 28.5 ± 3.1 mm (P < 0.05). In the C-D group, the number of endobronchial cuffs seen to be herniating out of the carina, the number of bronchoscopies during initial placement and on the lateral position, the number of total malposition intraoperative and the number of reposition manoeuvres intraoperative were significantly less than the C-P group or the C-C group (P < 0.05).

CONCLUSIONS

The length of the right main stem bronchus measured by the carina to distal margin of right upper lobe orifice method was more accurate than the other two methods in guiding the use of right sided double-lumen tube.

TRIALS REGISTRATION

Clinical Trials. gov. no. NCT04127903. Registered at https://register.

CLINICALTRIALS

gov on 16/10/2019.

The History of One-Lung Anesthesia and the Double-Lumen Tube

One-lung anesthesia presents many practical, anatomical, and physiological challenges to the anesthetist in modern day practice. The techniques and equipment that we use today have developed slowly over the course of the last century. The idea of isolated lung ventilation came from bronchospirometry studies by pioneering physiologists as early as 1871, and some of their original equipment was adapted for clinical use in the 1930s. Anesthetic techniques have generally been developed to facilitate surgical advances, and the development of double-lumen tubes is no exception. The development of the double-lumen tube was sporadic and occurred mainly to allow more complex thoracic procedures, mostly associated with suppurative lung disease. Once the need for independent ventilation of the lungs was identified in clinical practice, pioneers of the technique developed their own methods and often their own equipment. This led to the ability of the anesthetist to be able to control ventilation to each lung, including collapse of the operative lung and protection of the isolated lung against contamination. As these anesthetics became more reliable, the surgical scope for one-lung anesthesia began to broaden, and today one-lung ventilation is used to facilitate thoracic surgery, mainly on the lung, but also esophageal, thoracic wall, and mediastinal surgical procedures.

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.

Modified right-sided Broncho-Cath™ double lumen tube improves endobronchial positioning: a randomized study

OBJECTIVE

A left-sided double lumen tube is recommended for one-lung ventilation for most thoracic surgeries, but for certain indications, a right-sided double lumen tube (R-DLT) may be mandatory. Frequent malposition of R-DLTs has been reported. We propose an innovative modification of Mallinckrodt's Broncho-Cath R-DLT consisting of an enlarged area of the lateral orifice, and studied the impact of this modification on the adequacy of R-DLT positioning.

METHODS

Eighty adult patients scheduled for elective thoracic surgery were randomized into two groups: standard Broncho-Cath R-DLT, or modified Broncho-Cath R-DLT. After induction of anesthesia, the R-DLT was positioned using a fibreoptic bronchoscope. The position of the R-DLT was assessed on three occasions: with the patient supine (T1), then immediately following the patient's transfer to the lateral position (T2), and after repositioning of the tube, when needed, with the patient in lateral position (T3). A score ranging from 1 to 4 was accorded to the relative position of the right upper lobe (RUL) orifice in relation to the origin of the RUL bronchus.

RESULTS

The modified Broncho-Cath R-DLT was more frequently in an adequate position at T2: 77% vs 37% of patients (P = 0.0121), and easier to reposition at T3: 97% vs 74% of patients (P = 0.0109) in comparison to the standard Broncho-Cath R-DLT group.

CONCLUSION

These data suggest the superiority of the modified Broncho-Cath R-DLT compared to a standard Broncho-Cath R-DLT for optimal R-DLT positioning to facilitate one-lung ventilation during thoracic surgery.

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.

New landmarks improve the positioning of the left Broncho-Cath double-lumen tube-comparison with the classic technique

PURPOSE

To compare a new technique (NT) for positioning the left modified Broncho-Cath double-lumen tube (LM- DLT) by fibreoptic bronchoscopy (FOB) to the classic technique (CT).

METHODS

Sixty-one adult patients undergoing elective thoracic surgery with LM-DLT were randomly assigned to the NT or to the CT group. For the NT, the endoscopist confirms the left mainstem endobronchial intubation. The proximal edge of the blue bronchial cuff should not be visualized at the carina. Then, through the left bronchial lumen, by transparency across the wall of the tube, the position of the tube is adjusted so that the carina lies midway between the black radiopaque line and the top of the bronchial cuff. After this, the orifice of the left upper lobe (LUL) bronchus should be clearly seen. For the CT, the endoscopist uses the technique described by Benumof and Slinger. After lateral positioning of the patient, the LM-DLT was repositioned if the top of the endobronchial cuff was above the carina or when the LUL bronchus was obstructed.

RESULTS

The incidence of proximal repositioning was significantly less in the NT compared to the CT (16% vs 43%, P=0.007).

CONCLUSION

Using this new technique, the LM-DLT is inserted deeper in the left mainstem bronchus. This new landmark augments the range of movement that can be tolerated without requiring repositioning of the LM-DLT. This NT to position and to assess LM-DLT, by transparency across the wall of the tube with FOB, is better adapted to the LM-DLT and its recent modifications.

A quality improvement study of the placement and complications of double-lumen endobronchial tubes

To assess the complications of conventional and fiberoptic endobronchial intubations using reusable (Leyland, London) and disposable (Rüsch, Waiblinger, Germany; Sheridan, Argyle, NY) double-lumen tubes (DLTs), endobronchial intubations occurring over a 12-month period were prospectively studied at this hospital. Residents working with staff anesthesiologists placed either left or right reusable (Leyland) or disposable (Rüsch or Sheridan) DLTs. The DLT used, the use of fiberoptic bronchoscopy (FOB), findings at FOB if used during the intubation or operation, and complications occurring during the case (SpO2 < 90%, peak inflation pressure > 40 cm H2O, air trapping, poor lung isolation, and airway trauma) were recorded. Two hundred thirty-four intubations were analyzed (102 right, 132 left; 70 Leyland reusable DLTs, 66 Rüsch disposable tubes, and 98 Sheridan tubes). Physical signs alone were used to confirm tube position more frequently when Leyland tubes were placed compared with disposable tubes (79% v 39%, P < 0.0001). Rüsch and Sheridan DLTs had similar rates of conventional placement. Nineteen percent of reusable tubes and 44% of disposable tubes required position adjustments using FOB during the initial intubation (P = 0.0002). Disposable tubes also more commonly required readjustment using FOB during the operation (30% v 7%, P < 0.0005). Complications occurred in 42/234 patients (18%). The frequency of specific complications was: decreased SpO2, 9%; increased airway pressures, 9%; poor lung isolation, 7%; air trapping, 2%, and airway trauma, 0.4%. Right-sided Sheridan DLTs had a statistically higher incidence of malposition, resulting in poorer lung isolation.(ABSTRACT TRUNCATED AT 250 WORDS)