European Journal of Cardiovascular Medicine

Thoracic surgery often necessitates lung isolation, a critical component in ensuring optimal surgical conditions and patient safety. This is achieved through the utilization of double-lumen endotracheal tubes (DLTs), which facilitate selective ventilation of one lung while isolating the other. The accurate placement of these DLTs is paramount, as improper positioning can lead to inadequate isolation, compromising surgical exposure and patient outcomes. Despite established techniques for initial DLT placement, confirmation of correct positioning remains a challenge, and misplacements are not uncommon.

Bronchoscopy, a well-established diagnostic tool in respiratory medicine, has emerged as a promising adjunct for verifying DLT placement. By allowing direct visualization of the tracheobronchial tree, bronchoscopy provides a dynamic assessment of DLT positioning, enabling clinicians to confirm the placement accuracy and make timely adjustments if necessary.

This study aims to systematically assess the accuracy and effectiveness of bronchoscopy in confirming the proper positioning of DLTs in patients undergoing thoracic surgery. Through a prospective observational design, we seek to investigate the sensitivity and specificity of bronchoscopy in detecting DLT malpositioning, compare it with traditional confirmation methods, and ascertain its impact on surgical outcomes.

By shedding light on the clinical utility of bronchoscopy in DLT placement verification, this research endeavours to enhance the safety and precision of thoracic surgeries, ultimately benefiting patient care and surgical practice.

In our study, we used only left-sided double-lumen endobronchial tubes Because these are easily available and relatively easier to use in clinical practice.

The following study is conducted in MGM Super speciality Hospital Indore by the Anaesthesia department on thoracic cases posted by the CTVS department in the years 2022 to 2023.

This study utilizes a prospective observational design.

Data will be collected from 30 patients scheduled for elective thoracic surgery requiring lung isolation.

Inclusion criteria:

Adult patients (age ≥ 18) scheduled for elective thoracic surgery necessitating lung isolation with a double-lumen tube.

Exclusion criteria:

Patients with contraindications to Double lumen tube insertion or bronchoscopy, those unable to provide informed consent, ASA 4 status, and emergency cases.

Data Collection:

Preoperative patient data: Age – 18yrs and above

                                                Gender- Both Male and female

                                                ASA physical status- ASA 1, ASA 2, and ASA 3 patients are included in our study

Intraoperative data: Type of thoracic surgery, DLT size, initial placement technique, and bronchoscopy findings in supine and lateral positions.

Ethical Considerations:

Informed consent will be obtained from all participants.

Patient confidentiality and privacy were maintained throughout the study.

Method: -

Our study included 30 adult patients undergoing thoracic surgery, which required the use of left-sided double-lumen endobronchial tubes.

All patients were premedicated with tab Alprax 0.5mg, on the night before surgery and also on the morning of surgery. Inj. glycopyrrolate 0.2 mg and inj. Ondansetron 4mg IV stat was given just before induction. Anaesthesia was induced with propofol 2mgKg-1, fentanyl 2-4 microgramKg-1 and midazolam 0.05mgKg-1. Neuromuscular blockade was achieved with 0.1mgKg-1 of vecuronium and patients were ventilated with oxygen for 3mins. The adequate size of the left-sided double-lumen endobronchial tube (Portex sizes 35, 37, 39, and 41) was introduced into the patient's trachea after direct laryngoscopy.

Both tracheal and bronchial cuffs were inflated with air.

Confirmation of DLT placement was assessed initially by auscultation of the desired side of the lung by isolating it, capnography, and movement of the chest wall. Also, moisture during exhalation in the transparent proximal limb of DLT and on the catheter mount was noted. Maintenance of anaesthesia through gas was done with oxygen gas, nitrous oxide gas, and isoflurane during bronchoscopy and after bronchoscopy. For maintenance, intravenously fentanyl and vecuronium are given through infusion. ECG, pulse oximetry, capnography, invasive blood pressure, and arterial blood gases were monitored. With the patient in supine and lateral position, fibreoptic bronchoscopy (Ambu fibreoptic bronchoscope of size 3.8mm diameter with 600 of length) was performed to confirm the right position of tracheal and bronchial limbs into their respective bronchus. First, we inserted a bronchoscope into the tracheal lumen of the tube, and the following points were noted.

1. Tracheal carina visible or not visible.
2. Rt main bronchus visible or not
3. The left bronchial tube or bronchial cuff below the tracheal carina is visible or not visible.
4. Any Malposition of DLT. (Malposition would be defined as unable to isolate the desired lung and the DLT used would be too inside or outside or on the opposite side of the desired lung. The cuff is either herniating or not rightly inside the bronchus to isolate the lung).

The fibreoptic bronchoscope was then introduced to the bronchial lumen of the left double-lumen endobronchial tube and we observed the view of the left side bronchus - whether a clear view was obtained or not.

The demographic data of the 30 patients studied are shown in Table 1. Among 30 patients studied 9 were females and 21 were males. Surgery performed included 10 Lobectomy, 2 Pneumonectomies, 1 Tumour excision, 14 Decortication (in Tubercular Cases), 1 Diaphragmatic Plication, 1 hydatid Cyst Excision, 1 Fungal Ball Removal. Among all the above patients Right Thoracotomy was performed in 19 patients and 11 had left thoracotomy shown in Table 2.

Characteristics of 30 patients in Table 1.

Table 2: Distribution of Surgery Performed

In all the patients studied left-sided double-lumen tubes (DLT) (Sizes- 35, 37, 39, 41 fr) were used. The sizes and distribution of DLT among males and females are shown in Table 3

Table 3:

Of the sample studied (30 Patients), 9 were female and 21 were males. Out of 9 female patients, 7 female patients were intubated with left-sided DLT of size 35 Fr, and 2 were intubated with left-sided DLT of size 37 Fr. Out of 21 male patients, 11 male patients were intubated with left-sided DLT of size 37 Fr, 8 male patients were intubated with left-sided DLT of size 39 Fr, 2 male patients were intubated with left-sided DLT of size 41 Fr.

Out of 30 cases studied desired lung isolation was achieved in 26 cases on clinical evaluation (auscultation and chest expansion), in 4 cases DLT was not giving satisfactory results and repositioned properly using the bronchoscope. Details of the study with clinical evaluation and bronchoscopic evaluation in supine and lateral positions are shown in Table 4.

Table 4: Bronchoscopic findings of 30 patients after DLT placement

In our study investigating the placement of double-lumen endotracheal tubes (DLT) in the supine position, we confirmed the tube's position through hemithorax auscultation and observed chest rise in patients. Upon performing bronchoscopy on all subjects in the supine position, we discovered that out of the 30 patients examined, only 8 (26.67%) had a clear view of the carina using the bronchoscope. Among these 8 (26.67%) patients, we achieved a clear view of the right bronchus, the proximal left bronchial cuff, and the left-sided lung bronchial tree.

We observed bronchial cuff herniation of the left-sided DLT in 12 (40%) patients while in the supine position. This issue was rectified by mobilizing the DLT inside the left side of the bronchial lumen of the lungs. Additionally, in 5 (16.67%) patients, we noted that the DLT was positioned too deeply inside the left lung, resulting in the carina not being visible. Among the cases where left-sided DLT was found too deep inside the bronchus of the left side, in 4 cases blocking of left-sided bronchial lumen was observed. This issue was resolved by carefully retracting the DLT under direct vision. In 5 (16.67%) patients, we observed the left-sided DLT entering the right lung, which was corrected using the bronchoscope under direct vision.

Following DLT placement and confirmation of position of DLT by the anaesthesiologist, patients scheduled for thoracic surgery were subsequently repositioned into the lateral position. It was observed that during the transition from supine to lateral, the tube often became malposition. Specifically, in our study, we found that 2 patients in the lateral position exhibited left bronchial cuff herniation, which had developed during the transition from supine to lateral. This was corrected under direct vision using the bronchoscope. Additionally, in 2 patients, the DLT migrated too deeply into the lung, obscuring the carina. This was also corrected under direct vision.

DISCUSSION

The placement of double-lumen endotracheal tubes (DLT) is crucial for successful thoracic surgeries, as it enables selective lung ventilation and optimal surgical exposure. Among these patients, bronchoscopy allowed for visualization of key anatomical landmarks, such as the right bronchus, proximal left bronchial cuff, and the left-sided lung bronchial tree.

In our study we only used left-sided DLT because of the much greater positioning margin of safety compared to right-sided DLT5 also the right main bronchus is shorter than the left. Therefore, a left-sided DLT is used more commonly because of the lower risk of obstructing the right upper lobe bronchus6.

The most proximal acceptable position of a left-sided tube is when the left endobronchial cuff is just below the tracheal carina. With the tube in this position, the fibreoptic bronchoscope in the tracheal lumen will show the proximal part of the bronchial cuff to the left of the tracheal carina. The most distal acceptable position of a left-sided tube is when the tip of the left lumen is at the proximal edge of the left upper lobe bronchial orifice. The fibreoptic bronchoscope introduced through the tracheal lumen will show the left bronchial tube to the left of the carina. If the tip of the left lumen is placed in a more distal position, then the tip of the left lumen would progressively obstruct the left upper lobe bronchial orifice7.

Our study investigated the challenges and complications associated with left DLT placement in both the supine and lateral positions, highlighting the importance of vigilant monitoring and adjustment to ensure proper tube placement.

We utilized Clinical observation (hemithorax auscultation and observation of chest rise) to initially confirm DLT position in the supine position and bronchoscopic findings to correlate with the clinical finding. Clinical observation suggested the correct placement of DLT in 26 (86.67) cases studied. Clinical observation in 4 (13.34) cases out of 30 cases was not up to the mark and it has to be fixed with the help of DLT. However, bronchoscopy revealed that only a minority of patients (8 (26.67%) out of 30) had a clear view of the carina, indicating the limitations of physical examination alone in assessing DLT placement. In our study malposition was observed in 73.34% of cases, similar to our study malposition was also seen in a study done by Smith et al (48% of cases)1, Alliaume et al after auscultation did repositioning in 78% of left-sided double-lumen endobronchial tubes after fibreoptic bronchoscopy2. Lewis JW et al observed tube position with fibreoptic bronchoscopy, auscultatory assessment of placement was found to be incorrect in 38.0% of patients3. De Bellis et al observed that after blind intubation, 37% of double-lumen tubes required repositioning using flexible bronchoscopy4. Thus, a study done by us and other authors clearly showed that DLT placement should be done under vision using a bronchoscope as clinical methods like auscultation and chest rise itself are not enough to give better placement of DLT.

Among the malposition of DLT, one of the notable complications observed in our study was bronchial cuff herniation of the left-sided DLT, which occurred in 12 (40%) patients while in the supine position. This issue was successfully addressed by mobilizing the DLT inside the left bronchial lumen under vision, highlighting the importance of bronchoscopic guidance in correcting malposition tubes. Although on clinical evaluation it was not evident. This malposition if not corrected could lead to a mismatch of ventilation and successive complications.

Additionally, in 5 (16.67%) patients, the DLT was positioned too deeply inside the left lung, leading to the obscuration of the carina. Though on auscultation isolation of hemithorax was achieved in 1 case out of 5 (16.67%) cases, which on observing the DLT under vision through the tracheal lumen shows carina not visible. The chest expansion and auscultation were seen during the isolation of the lung, which could probably be explained by the smaller size of the DLT used,  which although it entered into the left-sided bronchus, its depth on the left side of the lung was just enough that tracheal part of left-sided DLT could manage to leak the gases to the opposite side of the chest and ventilate it. The bronchial lumen examined in this case through a bronchoscope had no obstruction as such. So clinically we achieved ventilation of both lungs selectively.

Among the above 4 cases out of 5 (16.67%) cases where the DLT was positioned too deeply inside the left lung and isolation couldn’t be achieved clinically. 2 Cases on examining through bronchoscope we found that carina was not visible at all and bronchial lumen showed blocking of left-sided bronchial lumen. Blocking of the left-sided bronchial lumen can be explained by curvature of the bronchus, which was not aligned correctly to the angle of the bronchial lumen of DLT.

In the other 2 cases where the DLT was positioned too deeply inside the left lung and isolation couldn’t be achieved clinically, in such cases carina was not visible when observed through the tracheal lumen and on observing through the bronchial lumen it was found that DLT went deep inside bronchus and affecting the ventilation of the upper lobe of left lung. The ventilation provided through it was not enough for chest expansion. Careful retraction of the DLT under direct vision resolved this issue, underscoring the value of bronchoscopy in optimizing tube placement.

In 5 (16.67%) patients it was observed that left-sided DLT was landing in the right side of the lung, although isolation of hemithorax was achieved but the bronchial part of left DLT was ventilating the right side of the lung and the tracheal part of DLT (left) was ventilating left side in left-sided DLT. On bronchoscopic examination, it was found that the angle of the bronchus on the left side was too acute to negotiate smoothly. Also, the expertise and experience of the anaesthetist were very important, as fewer incidences of left DLT tube going on right are seen when an experienced anaesthetist handles the thoracic cases with DLT. In all such cases, where the left DLT was moving to the right bronchus, examining properly through the bronchoscope the bronchial lumen of the left DLT was retracted above the carina and then safely redirected to the left side of the lung. If only by auscultation if we manage the case, then possibly ventilation mismatch could occur.

During the transition from the supine to the lateral position for surgery, we observed malpositioning of the DLT. This highlights the challenges associated with maintaining proper tube placement in situations like patient positioning changes from supine to lateral, neck extension or flexion during position change, surgical manipulation, bucking, or coughing by the patient because of inadequate depth. In our study, we noted left bronchial cuff herniation in 2 (6.67%) patients in the lateral position, which had developed during the repositioning process. Prompt correction under direct vision using bronchoscopy was essential to prevent potential complications such as inadequate lung isolation or airway trauma.

Furthermore, in 2 (6.67%) patients, the DLT migrated too deeply into the lung upon repositioning from supine to lateral, resulting in the obscuration of the carina. Again, bronchoscopic intervention allowed for the timely correction of this malposition, ensuring adequate ventilation and surgical access.

One more point that I would like to emphasize is that handling of DLT with an experienced person is very important as it could lead to fewer mispositioning incidences. The adequate size chosen for DLT is also important as smaller-sized DLT could go further into the lung leading to obscuring the carina and left lung ventilation.

our study sheds light on the critical role of bronchoscopy in confirming and adjusting the placement of double-lumen endotracheal tubes (DLT) for thoracic surgeries, particularly in challenging supine and lateral positions. We found that relying solely on physical examination methods, such as hemithorax auscultation and observation of chest rise, had limitations, as evidenced by the minority of patients with a clear view of the carina.

Bronchoscopy emerged as an invaluable tool in our study, enabling visualization of key anatomical landmarks and identification of complications such as bronchial cuff herniation and deep tube placement. Prompt intervention under direct vision allowed for the correction of these issues, ensuring proper tube placement and minimizing the risk of complications such as inadequate lung isolation or airway trauma.

The transition from supine to lateral positioning for surgery posed challenges, and frequent malpositioning of the DLT was observed. Left bronchial cuff herniation and migration of the DLT too deeply into the lung were notable complications encountered during this process. However, bronchoscopic intervention facilitated timely correction and optimized patient safety and surgical outcomes.

In summary, our study highlights the crucial role of bronchoscopy in ensuring optimal DLT placement for thoracic surgeries, emphasizing the need for meticulous monitoring and adjustment to mitigate complications and enhance patient outcomes.

1. Smith GB, Hirsch NP, Ehrenwerth J. Placement of double-lumen endobronchial tubes. Br J Anaesth 1986; 58:
2. Alliaume B, Coddens J, Deloof T. Reliability of auscultation in positioning of double-lumen endobronchial tubes. Can J
3. Anaesth 1992; 39: 687-90.
4. Lewis JW, Serwin JP, Gabriel FS et al. The utility of a double-lumentube for one-lung ventilation in a variety of noncardiacthoracic surgical procedures. J Cardiothor Vasc Anes 1992;5: 705-10.
5. de Bellis M, Accardo R, Di Maio M, La Manna C, Rossi GB, Pace MC, Romano V, Rocco G. Is flexible bronchoscopy necessary to confirm the position of double-lumen tubes before thoracic surgery? Eur J Cardiothorac Surg. 2011;40(4):912–916. doi: 10.1016/j.ejcts.2011.01.070. [PubMed] [CrossRef] [Google Scholar]Benumof JL, Brian Partridge L, Cairo Salvatierra et al. Margin of safety in positioning modern double lumen
6. Alfery DD, Benumof JL. Anesthesia for thoracic surgery, In:Miller RD editor, Anesthesia 4th edition New York: Churchill- Livingstone, 1994; 1692.
7. Jay Brodsky B, Mark shulman S, James Mark BD.Malposition of left sided double-lumen endobronchial tubes. Anesthesiology 1985; 62: 667-69.