How can bronchial obstruction occur during pneumonectomy. What are the risks and complications of tumor embolism during lung surgery. How can surgeons prevent and manage bronchial obstruction intraoperatively. What role does double-lumen endotracheal intubation play in preventing tumor embolism.

Understanding Bronchial Obstruction in Lung Cancer Surgery

Bronchial obstruction is a potentially life-threatening complication that can occur during lung cancer surgery, particularly pneumonectomy procedures. This article examines a rare case of bronchial obstruction caused by tumor embolism during a left pneumonectomy, despite the use of a double-lumen endotracheal tube (DLT) for lung isolation.

What is bronchial obstruction?

Bronchial obstruction refers to a blockage in the airways that impedes normal airflow. In the context of lung cancer surgery, it can occur when tumor fragments dislodge and travel to the contralateral (opposite) lung, obstructing the main bronchus. This complication is particularly dangerous as it can severely compromise oxygenation and ventilation during surgery.

Why is pneumonectomy considered high-risk?

Pneumonectomy, the surgical removal of an entire lung, is regarded as a high-risk procedure due to various potential complications during and after surgery. These complications may include:

• Respiratory failure
• Cardiac arrhythmias
• Bronchopleural fistula
• Pneumonia
• Pulmonary edema
• Tumor embolism

The complexity of the procedure and the significant impact on lung function contribute to its high-risk status.

The Role of Double-Lumen Endotracheal Tubes in Lung Isolation

Double-lumen endotracheal tubes (DLTs) are specialized devices used for lung isolation during thoracic surgeries. They allow for independent ventilation of each lung, which is crucial in procedures like pneumonectomy.

How does a double-lumen endotracheal tube work?

A DLT consists of two separate lumens:

1. A longer lumen that extends into one main bronchus
2. A shorter lumen that ends in the trachea

This design allows anesthesiologists to ventilate one lung while collapsing the other, facilitating surgical access. The inflatable cuffs on the DLT create a seal, theoretically preventing the migration of material between the two lungs.

Can DLTs prevent tumor embolism?

While DLTs are generally considered effective in preventing tumor embolism during lung surgery, this case study demonstrates that they are not foolproof. Factors such as aggressive surgical manipulation, tumor fragility, or improper DLT placement may still lead to tumor dislodgement and embolism.

Case Study: Tumor Embolism During Left Pneumonectomy

This case involves a 59-year-old male patient undergoing a left pneumonectomy for non-small cell lung cancer. Despite the use of a right-sided 37-Fr DLT for lung isolation, the patient experienced a near-total obstruction of the right main bronchus due to tumor emboli during the procedure.

What were the key preoperative findings?

Preoperative evaluations revealed:

• An endobronchial mass in the distal left main bronchus extending to the proximal left lower lobe
• Complete obstruction of the affected bronchus
• Forced expiratory volume in 1 second (FEV1) of 1.83 L
• Arterial blood gas analysis: pH 7.43, pCO2 49 mmHg, pO2 76 mmHg at room air

These findings indicated significant airway involvement and moderately impaired lung function.

How did the surgical team manage lung isolation?

The anesthesia team employed a 37-Fr right-sided DLT for lung isolation. They confirmed proper placement using fiberoptic bronchoscopy. Initial ventilation parameters included:

• Two-lung ventilation: Tidal volume 500 ml, peak airway pressure 26 cmH2O
• One-lung ventilation: FiO2 100%, tidal volume 400 ml, respiratory rate 15/min, peak airway pressure 25 cmH2O

These measures initially provided adequate oxygenation and ventilation.

Intraoperative Complications: Recognizing and Managing Bronchial Obstruction

Approximately 3 hours into the procedure, following the division of the left bronchus, the surgical team observed sudden changes in ventilation parameters, indicating a potential complication.

What were the signs of bronchial obstruction?

The key indicators of bronchial obstruction included:

• A sudden increase in peak airway pressure
• Reduction of expired tidal volume to 50 ml
• Difficulty in ventilating the patient

These abrupt changes alerted the team to a potential airway emergency.

How was the obstruction diagnosed?

The surgical team performed an intraoperative fiberoptic bronchoscopy, which revealed a near-total obstruction of the right main bronchus due to tumor emboli. This diagnostic step was crucial in identifying the cause of the ventilation difficulties and guiding subsequent management.

Challenges in Managing Tumor Embolism During Surgery

The management of tumor embolism during lung surgery presents significant challenges, requiring quick thinking and coordinated action from the surgical and anesthesia teams.

Why was bronchoscopic removal unsuccessful?

Initial attempts to remove the tumor embolus through bronchoscopic suction and forceps were unsuccessful. This difficulty could be attributed to several factors:

• The size and consistency of the tumor fragment
• Limited maneuverability within the bronchus
• Risk of further fragmenting the embolus
• Time pressure due to compromised ventilation

These challenges necessitated a more invasive approach to resolve the obstruction.

What alternative approach did the surgical team employ?

Faced with the failure of bronchoscopic removal, the surgical team took the following steps:

1. Reopened the left bronchial stump
2. Extracted the tumor embolus under bronchoscopic guidance
3. Ensured complete removal of obstructing material
4. Re-established ventilation to the right lung

This approach, while more invasive, allowed for direct access to the obstructing embolus and its successful removal.

Implications for Future Thoracic Surgical Procedures

This case highlights the potential for rare but serious complications during lung cancer surgery, even when using established preventive measures like DLTs. It underscores the need for vigilance and preparedness in managing unexpected intraoperative events.

How can surgical teams better prepare for potential tumor embolism?

To enhance preparedness for tumor embolism during lung surgery, teams can:

• Conduct thorough preoperative assessments of tumor location and friability
• Ensure proper placement and function of DLTs
• Maintain constant vigilance for changes in ventilation parameters
• Have bronchoscopy equipment readily available
• Develop and rehearse emergency protocols for airway obstruction
• Consider alternative lung isolation techniques in high-risk cases

These measures can improve the team’s ability to quickly recognize and respond to potential complications.

What are the potential long-term outcomes for patients experiencing intraoperative tumor embolism?

The long-term outcomes for patients who experience intraoperative tumor embolism can vary depending on several factors:

• Speed of recognition and management of the complication
• Extent of airway obstruction and duration of compromised ventilation
• Presence of any residual tumor fragments
• Overall health status and lung function of the patient
• Potential impact on cancer staging and prognosis

Prompt and effective management, as demonstrated in this case, can minimize long-term consequences and allow for successful completion of the intended cancer treatment.

Advancements in Thoracic Surgery Techniques and Technology

The field of thoracic surgery continues to evolve, with ongoing research and development aimed at improving patient outcomes and reducing the risk of complications like tumor embolism.

What new technologies are being developed to prevent tumor embolism?

Emerging technologies and techniques to prevent tumor embolism during lung surgery include:

• Advanced imaging techniques for better preoperative tumor assessment
• Novel lung isolation devices with enhanced sealing capabilities
• Intraoperative real-time monitoring systems for early detection of emboli
• Minimally invasive surgical approaches that may reduce tumor manipulation
• Improved tissue sealants and surgical instruments for secure tumor resection

These advancements hold promise for further reducing the risk of this rare but potentially fatal complication.

How might robotic-assisted thoracic surgery impact the risk of tumor embolism?

Robotic-assisted thoracic surgery offers several potential benefits that could reduce the risk of tumor embolism:

• Enhanced visualization and magnification of the surgical field
• Greater precision in tissue manipulation and dissection
• Reduced need for aggressive handling of tumor-bearing lung tissue
• Ability to perform complex procedures through smaller incisions
• Potential for improved lymph node dissection and staging

While robotic surgery may offer these advantages, it’s important to note that the risk of tumor embolism cannot be completely eliminated, and vigilance remains crucial.

In conclusion, this case study of bronchial obstruction during pneumonectomy highlights the ongoing challenges in thoracic oncologic surgery. Despite the use of established preventive measures like double-lumen endotracheal tubes, rare complications can still occur. The successful management of this case demonstrates the importance of quick recognition, teamwork, and adaptability in the operating room. As surgical techniques and technologies continue to advance, thoracic surgeons and anesthesiologists must remain vigilant and prepared to address unexpected complications, ensuring the best possible outcomes for patients undergoing lung cancer surgery.

Bronchial obstruction by tumor embolus of contralateral lung during pneumonectomy: report of a case | Journal of Cardiothoracic Surgery

• Case report
• Open Access
• Published: 19 February 2013

• Dong Kyu Lee¹,
• Heezoo Kim¹,
• Sang Ho Lim¹,
• Young Ho Choi² &
• …
• Hyun Koo Kim² 

Journal of Cardiothoracic Surgery
volume 8, Article number: 26 (2013)
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Abstract

Bronchial obstruction due to a tumor embolus of the contralateral lung during pneumonectomy is an uncommon and fatal complication. According to previous cases, a bronchial balloon of double-lumen endotracheal tube (DLT) could prevent a dislodged tumor from traveling to the contralateral lung. We experienced a tumor embolism from the bronchus with cancer to the other bronchus despite applying DLT. A 59-year-old male with endobronchial lung cancer underwent a left pneumonectomy. One-lung ventilation was established by the right-sided DLT. After a left bronchial division, a sudden increase of peak airway pressure and reduction of the expired tidal volume to 50 ml was observed. Intraoperative fiberoptic bronchoscopy showed a near total obstruction of the right main bronchus due to tumor emboli. It was not possible to remove the tumor embolus through bronchoscopic suction and forceps. Therefore, we reopened the left bronchial stump and successfully extracted tumor embolus under bronchoscopic guidance.

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Background

Surgery is one of the curative treatments for patient with primary lung cancer, but pneumonectomy is regarded as a high-risk procedure owing to various complications during peri- and postoperative periods. Because pneumonectomy is a high-priority indication of one-lung ventilation, various methods of lung separation could be applied. However, in the case of pneumonectomy due to endobronchial tumor, lung separation methods using single-lumen tube or bronchial blockers failed to prevent bronchial obstruction of the ventilated lung due to an embolic tumor during operation and this event caused a life-threateneing complication [1–4]. It is believed that an inflated balloon of DLT could protect embolic tumor dislocation into the ventilated lung. We reported a case with tumor emboli dislocation during pneumonectomy even under complete separation between both bronchi by DLT. We regarded that a tumor dislocation to a ventilated lung can occur due to an aggressive manipulation of the contralateral lung during the operation despite the use of DLT.

Case presentation

A 59-year-old male patient with a non-small cell lung cancer was scheduled for a left pneumonectomy. Chest computed tomography (CT) revealed that an endobronchial mass was located in the distal left main bronchus to the proximal left lower lobe with complete obstruction, which was consistent with a bronchoscopic examination (Figure 1). Forced expiratory volume in 1 second was 1.83 L in the pulmonary function test and arterial blood gas analyses were pH 7.43, pCO₂ 49 mmHg, and pO₂ 76 mmHg at room air.

Figure 1

An endobronchial tumor (arrow) in the distal left main bronchus was shown in the chest computed tomography (A) and bronchoscopy (B).

Full size image

When he arrived at the operation room, oxygen saturation was maintained at 96% at room air and was increased to 100% immediately after preoxygenation maneuver. A 37-Fr right-sided DLT (BronchoCathTM, Mallinckrodt Medical Inc., Athlone Co., Westmeath, Ireland) was placed for lung separation under fiberoptic bronchoscopy (FOB, LF-2, flexible fiberscope, Olympus, Tokyo, Japan). During two lung ventilations with a tidal volume (TV) of 500 ml, the peak airway pressure (PAP) was 26 cmH₂O. We performed FOB and confirmed that the bronchial balloon was in a proper position. Next, right-sided one-lung ventilation was initiated with clamping the tracheal side of the DLT. Ventilation was maintained with FiO₂ 100%; TV 400 ml; respiration rate 15 per minute and PAP was maintained at approximately 25 cmH₂O. After 15 minutes, the arterial blood gas analyses were pH 7.54, pCO₂ 29 mmHg, and pO₂ 516 mmHg. Approximately 3 hours after the start of the operation, and shortly after the entire left lung was extracted by a division of the left main bronchus, the PAP suddenly increased and reached up to 50 cmH₂O and the expired TV was below 50 ml. We suspected a cuff malposition, and immediately performed FOB. The bronchial cuff was in an adequate position without cuff herniation, and the cuff volume was enough to seal the right main bronchus, but we found a tumor embolus at the end of the bronchial side tube, which produced a near total obstruction of the right main bronchus. We promptly tried to extract the mass by performing suctioning; it was useless. In order to gain time for the next procedure and to prevent hypoxemia, we introduced bronchoscope, which have a suctioning channel through the left-sided lumen of DLT, passed over the embolic tumor mass to place the tip of bronchoscope on distal part of the right main bronchus and supplied oxygen through suctioning channel with high flow (10 ml/min). At this time, manual bagging with anesthesia bag produced various expired TV from 30 to 300 ml. Another bronchoscope (LF-DP, flexible fiberscope, Olympus, Tokyo, Japan) and a basket (FG-51D, disposable grasping forceps, Olympus, Tokyo, Japan) were applied to extract the embolic tumor mass through the right-sided lumen of DLT. However, it was not easy to retrieve the mass using a basket or suctioning, because the nature of the embolic mass was too soft. During these attempts, vital sign was remained blood pressure 100/60 mmHg, heart rate 90/min, and SaO₂ 92-95%. About 20 minutes later, SaO₂ gradually dropped toward 85%, and eventually, blood pressure decreased 75/50 mmHg. Because bronchoscope itself could be a major obstacle to a hypoxemia-prone patient, we abandoned FOB and removed one bronchoscope, which was introduced later. Vital sign was corrected with small dose inotropics and fluid resuscitation and SaO₂ recovered around 98% with manual ventilation with anesthesia bag. We decided to extract the embolic mass through the left main bronchial stump under the vision of a flexible fiberoptic bronchoscope. DLT was withdrawn until the tip of the bronchial side tube reached above the carina, and the operator reopened the left main bronchial stump, and removed the embolic tumor mass with curved long forceps (Figure 2). Next, we advanced the DLT with the guide of a bronchoscope towards the right main bronchus, and the one-lung ventilation was restored. Duration of episode was about 30 minutes. At the end of the anesthesia, the patient was extubated safely with adequate spontaneous ventilation.

Figure 2

(A) The gross specimen showed that the tumor was located in the distal left main bronchus. (B) The tumor emboli (size: 1.7 × 1.6 × 0.5 cm) was removed from the right main bronchus.

Full size image

Conclusion

The embolic tumor obstruction of the contralateral bronchus during a pneumonectomy is a rare but catastrophic complication. Only a few cases have been reported regarding this complication, and the results varied from complete recovery to death [1–9]. In most reported cases, a single-lumen endotracheal tube was used, but this does not ensure lung separation [1, 5, 6]. When the bronchial blocker, including the univent tube, was used, the balloon of the blocker should be retracted to facilitate the bronchial suture, which causes this type of accident [2]. Even though a double-lumen tube was applied, an embolic tumor obstruction occurred when the tube exchanged to a single-lumen tube or extubation at the end of anesthesia [3, 7]. However, during the operation, most authors believe that an embolic tumor dislocation can be prevented when the balloon was located in the opposite side of the main bronchus using a DLT [1–4]. At the same time, we experienced an embolic tumor obstruction of the opposite main bronchus during the operation without any manipulation of the bronchial balloon.

Most reported cases of embolic tumor obstruction were squamous cell carcinoma or carcinosarcomas, which are known to be friable tumors [6, 10]. In this case, the pathologic was pleomorphic carcinoma, which was soft, sticky, and easily compressible. In addition, repetitive partial dislocation of the bronchial balloon by surgical manipulation around the hila area could make the tumor mass to cross over to the bronchial balloon (Figure 3). Therefore, the embolic tumor obstruction can happen at any time during pneumonectomy even if we use DLT.

Figure 3

Schematic figure of the left endobronchial mass moving across the bronchial balloon to the right main bronchus during a surgical manipulation around the hilar area.

Full size image

When bronchial obstruction by embolic tumor mass occurred, the best choice of treatment is depend on the process of surgery, patient position, size and number of embolic mass, site of obstruction, method of maintaining one-lung ventilation, and so on. Extraction of embolic mass with FOB requires experienced person and adequate equipment. Because of the limitation in the instruments with FOB, rigid bronchoscope could be a better choice of treatment. However, in this case, because the patient was in the right-decubitus position and left chest wall remained opened, rigid bronchoscopy was not easy to perform. Therefore, surgeon reopened the left main bronchial stump, and removed the embolic tumor mass with curved long forceps under the vision of a flexible fiberoptic bronchoscope.

It is important to recognize bronchial obstruction as early as possible with continuous monitoring. Any changes regarding the PAP, SaO₂, TV, end-tidal CO₂, and other parameters for ventilation monitoring should be continuously checked and evaluated. Frequent FOB is also highly recommended when bronchial obstruction is suspected, especially before and after a bronchial resection.

Consent

The written informed consent was obtained from the patient for publication of this case report and all accompanying images including CT, X-ray and bronchoscopic findings. A copy of the written consent is available for review by the Editor-in-chief of this journal.

Abbreviations

DLT:

Double-lumen tracheal tube

CT:

Computed tomography

FOB:

Fiberoptic bronchoscopy

TV:

Tidal volume

PAP:

Peak airway pressure.

References

1. Bollen EC, Van Duin CJ, Van Noord JA, Janssen JG, Theunissen PH: Tumor embolus in lung surgery. A case report and review of the literature. Eur J Cardiothorac Surg. 1993, 7: 104-106. 10.1016/1010-7940(93)90190-M.

   Article 
   CAS 
   PubMed 

   Google Scholar 

2. “>

   Markowicz P, Fossier T: Right main bronchus tumoral obstruction during left pneumonectomy. Ann Fr Anesth Reanim. 2006, 25: 648-651. 10.1016/j.annfar.2006.02.014.

   Article 
   CAS 
   PubMed 

   Google Scholar 

3. de Lange JJ, van Mourik JC, den Otter G: A fatal complication following pneumonectomy. Ned Tijdschr Geneeskd. 1989, 133: 32-34.

   CAS 
   PubMed 

   Google Scholar 

4. Janssen CW: Death during pneumonectomy from endobronchial tumour embolus. A case report. Scand J Thorac Cardiovasc Surg. 1976, 10: 173-174. 10.3109/14017437609167787.

   Article 
   PubMed 

   Google Scholar 

5. Fox EJ, Fox JWC, Crandell DL: An unusual cause of hypoxia under anesthesia. Anesthesiology. 1966, 27: 867-868. 10.1097/00000542-196611000-00028.

   Article 

   Google Scholar 

6. “>

   Pathi V, Ramphal P, Sutherland F, Kirk A: Endobronchial tumor embolism: a preventable cause of death. J Thorac Cardiovasc Surg. 1996, 112: 844-845. 10.1016/S0022-5223(96)70077-6.

   Article 
   CAS 
   PubMed 

   Google Scholar 

7. Chadha R, Mehta SP: Unusual airway obstruction leading to contralateral pneumothorax following pneumonectomy. Anaesthesia. 2000, 55: 705-

   Article 
   CAS 
   PubMed 

   Google Scholar 

8. Tan CG, Shen L, Garske L, Tran K: Concurrent acute endobronchial and endotracheal tumour embolism. Thorax. 2010, 65: 464-10.1136/thx.2009.117929.

   Article 
   CAS 
   PubMed 

   Google Scholar 

9. Verstraeten SE, van Straten AH, Korsten HH, Weber EW, Wielders PL, Berreklouw E: Inability to ventilate after tube exchange postoperative to pneumonectomy. Case Rep Anesthesiol. 2012, Epub 2012 Apr 5

   Google Scholar 

10. Chen K, Varon J, Wenker OC: Malignant airway obstruction: recognition and management. J Emerg Med. 1998, 16: 83-92. 10.1016/S0736-4679(97)00245-X.

    Article 
    CAS 
    PubMed 

    Google Scholar 

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Authors and Affiliations

1. Department of Anesthesiology and Pain medicine, Korea University Guro Hospital, Korea University College of Medicine, Seoul, South Korea

   Dong Kyu Lee, Heezoo Kim & Sang Ho Lim

2. Department of Thoracic and Cardiovascular Surgery, Korea University Guro Hospital, Korea University College of Medicine, 97 Guro-donggil, Guro-gu, Seoul, 152-703, South Korea

   Young Ho Choi & Hyun Koo Kim

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Hyun Koo Kim.

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Competing interests

The authors declare that they have no competing interests.

Authors’ contributions

HK Kim and YH Choi performed surgery and DK Lee performed general anesthesia and provided one-lung ventilation during operation. HZ Kim and SH Lim participated in bronchoscopic mass extraction and maintaining ventilation during procedure. HK Kim and DK Lee were major contributors in writing the manuscript. All authors read and approved the final manuscript.

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Rescue procedure for left main bronchus obstruction after patent ductus arteriosus clipping: a case report | Surgical Case Reports

Rescue procedure for left main bronchus obstruction after patent ductus arteriosus clipping: a case report

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• Case Report
• Open Access
• Published: 28 June 2018

• Yukiko Ban 
  ORCID: orcid.org/0000-0002-8820-4889¹ &
• Masakazu Abe¹ 

Surgical Case Reports
volume 4, Article number: 67 (2018)
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Abstract

Background

Obstruction of the left main bronchus is a rare but life-threatening complication following the closure of patent ductus arteriosus by surgical clips. We report a successful rescue procedure for this complication in a premature infant.

Case presentation

A 24-week gestational age premature girl weighing 903 g underwent surgical clipping for patent ductus arteriosus at the age of 24 days after birth. Bronchoscopy revealed the left main bronchus obstruction due to the clip compression at 6 h later after the surgery. The patient underwent a rescue re-exploration for this serious complication. New clips were applied to both the intrapericardial and the aortic ends of the patent ductus arteriosus respectively. And then the previous clips, compressing the left main bronchus, were gently removed from the ductus without ductus injury through a re-thoracotomy.

Conclusions

Surgeons should be aware of the possible complication and take care not to place patent ductus arteriosus clips obliquely toward the bronchus.

Background

Patent ductus arteriosus (PDA) is a relatively common and harmful condition in premature infants. PDA injury, recurrent laryngeal, or phrenic nerve injuries are well-recognized complications in surgical closure of PDA. Obstruction of the left main bronchus is a rare complication following PDA closure with surgical clips. Because PDA is located close to the left main bronchus, inappropriate placement in the size, position, depth, and/or angle of the clips may cause serious airway obstruction. We report a case of obstruction of the left main bronchus following PDA closure with surgical clips and a successful rescue procedure for this life-threatening complication without PDA injury.

Case presentation

A 24-week gestational age premature girl weighing 903 g underwent surgical intervention for PDA at the age of 24 days after birth. The PDA was 3 mm in diameter and closed with two medium-sized, 4.5-mm-long surgical clips through a left thoracotomy. Although we recognized atelectasis of the left lung after the PDA clipping, it was improved by the adjustment of the airway pressure and tracheal tube position except for a part of the left lower lobe. However, chest X-ray film after the procedure still showed atelectasis of the left lung (Fig. 1). In spite of meticulous respiratory treatments, left atelectasis did not improve at all. The patient developed critical desaturation 6 h after surgery and required high airway pressure for ventilation. Bronchoscopy revealed that the left main bronchus was occluded completely by the external compression of the PDA clips at the lateral wall (Fig. 2). The patient immediately underwent a rescue re-exploration for this serious complication.

Fig. 1

Chest X-ray after PDA ligation showed completely collapsed left lung

Full size image

Fig. 2

Bronchoscopy showed a complete obstruction of the left main bronchus (white arrow) (RMB = right main bronchus)

Full size image

At re-exploration, one of the tips of the clips was tilted anteriorly and caudally and appeared to be applied obliquely toward the carina of the trachea. First, we prepared that the aorta could be temporarily clamped above and below the PDA. We applied two new clips on both ends of the PDA; one clip was placed on the intrapericardial pulmonary end of the PDA through a pericardiotomy, and another clip was placed on the aortic end (Fig. 3a, b). Subsequently, the previously applied two PDA clips were carefully removed from the PDA (Fig. 3b). This procedure was accomplished without PDA or airway injuries. Atelectasis of the left lung immediately improved after the rescue procedure. The postoperative course was uneventful, and the patient was extubated 3 days later.

Fig. 3

Surgical procedure. a PDA was clipped at the proximal end through a pericardiotomy (white arrow). b Another new clip was applied on the aortic end (white arrow), and the previous two clips were safely removed (yellow arrow) (Ao = aorta; LPA = left pulmonary artery; MPA = main pulmonary artery; PDA = patent ductus arteriosus; RSCA = right subclavian artery)

Full size image

Discussion

Obstruction of the left main bronchus is a rare but life-threatening complication of PDA closure with surgical clips. Harris et al. [1] reported that the PDA clip had been placed across the left main bronchus and caused the left main bronchus obstruction. A significant compression of the left main bronchus by a surrounding fibrous mass was noted, and they needed to remove the mass and skeletonize the left main bronchus 2 months after the PDA surgery. Bhat et al. [2] reported that a single PDA clip was applied to both the PDA and the left main bronchus, and they needed to repair the left main bronchus injury 5 days after the PDA surgery. In these cases, chest computed tomography showed the clip applied across the left main bronchus.

In our case, the possibility that the PDA clip was applied across the left main bronchus was presumed to be low, considering the clip size and PDA diameter. We believe that closing the PDA on both ends of the PDA in advance would prevent hemorrhage in case of PDA injury during clip removal. Approaching through a pericardiotomy, the new clip on the pulmonary end was placed away from the carina and did not cause airway obstruction. Extensive dissection of the clipped PDA was hazardous; therefore, we clipped PDA again with minimal dissection. If new clips could not be applied both ends of the PDA, aortic and/or left pulmonary artery clamp might be useful.

In the present case, an inappropriate placement angle of the clips resulted in the airway obstruction. The left main bronchus is located close beneath to the PDA and has a markedly thin wall of fragile cartilages in premature infants. A rigid metal clip placed inappropriately on the PDA compresses and occludes the fragile airway easily. Surgeons should apply PDA clips carefully after considering their position, angle, and depth to avoid airway complications. In order to clip PDA without airway obstruction, surgeons should hold a clip vertically and apply it to the extreme aortic end of PDA.

It is important not to hesitate to perform re-exploration in case of suspected airway obstruction by PDA clips to prevent a deleterious outcome. Both previously documented reports suggest that the surgical rescue procedure may become complicated if the re-exploration is performed late after the initial operation. An early bronchoscopic detection of the complication is necessary to prevent a more complicated reoperation. Surgeons, therefore, should be aware of this possible complication.

Conclusions

We described left main bronchus obstruction after patent ductus arteriosus clipping. Surgeons should be aware of this possible complication and take care not to place the PDA clips toward the left main bronchus.

Abbreviations

PDA:

Patent ductus arteriosus

References

1. Harris LL, Krishnamurthy R, Browne LP, Morales DL, Friedman EM. Left main bronchus obstruction after patent ductus arteriosus ligation: an unusual complication. Int J Pediatr Otorhinolaryngol. 2012;76:1855–6.

   Article 
   PubMed 
   CAS 

   Google Scholar 

2. Bhat AN, John J, Riyas MK, AlKurdi B, Salama H. Inclusion of the left main bronchus in the clip used to occlude the ductus arteriosus in a premature baby: an unexpected complication. Indian J Anaesth. 2014;58:213–5.

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Authors and Affiliations

1. Department of Cardiovascular Surgery, Ibaraki Children’s Hospital, 3-3-1, Futabadai, Mito, Ibaraki, 311-4145, Japan

   Yukiko Ban & Masakazu Abe

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YB operated on the patient and drafted the manuscript. MA participated in the surgery and revised the manuscript. Both authors read and approved the manuscript.

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Yukiko Ban.

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Bronchial obstruction and atelectasis and retention cysts

00:00

Igor Evgenievich Tyurin , professor, doctor of medical sciences :

– We start now with macroscopic changes in the form of atelectasis, retention cysts. You can start your presentation.

(Slide show) .

“Bronchial obstruction and atelectasis and retention cysts” .

The main issues that will be the focus of our attention today. Normal anatomy of the lung lobes in X-ray and CT images, naturally, obstructive atelectasis and other types of atelectasis that can occur in terms of differential diagnosis, features of semiotics. And also in conclusion, a little about retention cysts as a special form of pathology of the bronchial tree, which occurs as a result of a violation of bronchial patency.

(Slide show) .

I will very briefly recall a few well-known rules (or truths) related to the location of the lobes of the lungs. Today we will not touch on the segmental structure of the lungs – this is a separate topic and, probably, we will devote a separate session to this. But in the most general form, the lobes of the lung are depicted or projected on x-rays in approximately this way.

(Slide show) .

You remember well that there are three lobes in the right lung: upper, middle, lower. The left lung has two lobes, which are separated by an interlobar fissure: the upper and lower lobes. Here they are shown in different colors.

It is clearly seen that the oblique interlobar fissure starts from the diaphragm and continues towards the spine. The horizontal interlobar fissure starts from the root of the lung and is located almost horizontally towards the chest wall, towards the anterior part of the chest wall.

You can also clearly see that on the AP and lateral survey X-rays there is an obvious superimposition of individual lobes on top of each other. This is especially evident in direct projection. Therefore, of course, when it comes to the pathology of the lobes and segments of the lungs, radiologists (as well as the attending physicians) still use lateral projection images more often. This allows you to accurately determine the topic of changes and evaluate which changes, where exactly these or those changes are located.

02:18

(Slide show) .

Let me remind you, oblique interlobar fissure – from the border of the anterior middle third of the diaphragm through the root of the lung to the spine. Usually this is the fourth, less often the fifth, sometimes the third thoracic vertebra. In the form of a straight line or almost a straight line.

Horizontal interlobar fissure, which normally exists in the right (sometimes, as a developmental variant, it is also observed in the left lung) – from the root of the lung, from the middle of the oblique interlobar fissure to the anterior surface of the chest wall slightly at an angle to the diaphragm.

Accordingly, the horizontal interlobar fissure on the right separates the upper and middle lobes. And the oblique interlobar fissure separates the upper and middle lobes to the right of the lower, and in the left lung – the upper lobe from the lower.

(Slide show) .

If we move from this semiotics to a computed tomography image, we can conditionally see interlobar fissures (oblique interlobar fissures) in cross section.

Let’s take a computed tomography section that passes at the level of the aortic arch. It is shown in red in the center of this schematic. In this schematic representation, we see that most of the anterior chest cavity is occupied by the upper lobes of the lungs. Horizontally, oblique interlobar fissures are practically located. And also at the posterior surface of the chest wall, one can observe the tops of the lower lobe – these are usually the sixth segments.

(Slide show) .

If we go down, to the level of the base of the heart, to the level of the lower pulmonary veins, naturally, in the mediastinum we see the chambers of the heart: right, left ventricle, right, left atrium. Accordingly, the middle lobe on the right, the reed segments on the left and the main array of the lower lobes. They are located in the back of, respectively, the right and left hemothorax.

Of course, with computed tomography, we get the opportunity to more accurately, in more detail assess the location of anatomical structures in the chest cavity. In many cases, of course, this helps in assessing the condition of the respiratory tract.

(Slide show) .

Let me remind you that due to the structure of the bronchial tree, we distinguish bronchi of various calibers. In general, the bronchi as airways and respiratory sections of the lung, which end in small bronchi (acini and alveoli) – this is schematically represented here. Accordingly, the bronchi (there are usually more than 20 generations of bronchi) are airways.

Characteristically, the violation of bronchial patency at each level of such a dichotomous division of the bronchial tree is accompanied by peculiar changes in the chest cavity and lung tissue. They have a fairly regular appearance, regular changes in x-ray and tomography.

(Slide show) .

When it comes to obturation (partial or complete obstruction of the large bronchus), atelectasis occurs in most cases. Partial, complete – depending on various reasons and various factors. As a rule, this is a pathology of a lobe or segment of the lung, which manifests itself in the form of a decrease in volume, an increase in density, and a decrease in the airiness of the lung tissue.

This process can go through several successive stages in a certain order. It can occur very quickly – almost instantly. But the main result, in most cases, is indeed atelectosis of a part of the lung.

When bronchi of medium caliber are involved in the process (from subsegmental and further to intralobular practically bronchi – all bronchi of medium caliber having a cartilaginous framework), as a rule, we observe the occurrence of retention cysts. Atelectasis in this situation occurs, of course, but much less frequently. These are segmental, subsegmental atelectasis – we observe them much less frequently than lobar atelectasis, atelectasis of the lobes.

If we are talking about the pathology of the small bronchi of the distal respiratory tract (primarily bronchioles), this is a violation of bronchial patency. Narrowing or obstruction of these small bronchi leads to the development of broncholithiasis, leads to the development of air traps, to the respiratory collapse that occurs during exhalation. And also, of course, bronchiectasis as a manifestation of the pathology of small bronchi as a result of filling their lumen with pathological contents and sometimes simply expanding, filling them with air. Irina Alexandrovna will talk about this in detail today.

(Slide show) .

Atelectasis, I remind you, is an incomplete stretching or vice versa, an incomplete collapse of the lung tissue, a pathological condition of the lung or some part of it, in which the pulmonary alveoli do not contain air or contain it in a reduced amount and appear to be collapsed. This is how most of the medical encyclopedias that are available today define it.

This means that atelectasis may or may not be complete. The lung tissue, which is located in the zone of atelectasis formation, may be partially airy – then we are talking about partial atelectasis. Or be completely airless – then we see quite intense shading.

07:46

(Slide show) .

Types of atelectasis.

Congenital atelectasis is a condition where the lung does not expand at the time of birth. These are non-breathing lungs or parts of them in a newborn. This is a completely special state, of course, we will not touch on this issue today.

In most cases, these are still acquired atelectasis, which are observed in children and adults. This is a secondary collapse of the alveoli, the air alveoli in the previously breathing lung.

(Slide show) .

Species. Different classifications, different groupings, different systems for isolating different types of atelectasis. But most often, obstructive atelectasis is still isolated – resulting from blockage of a relatively large bronchus.

Compression atelectasis, which results from compression of the lung tissue by some usually extrapulmonary cause. Say, a high-lying diaphragm, fluid or air in the pleural cavity, large emphysematous bullae. We talked about this at the last lecture, and I showed such compression atelectasis.

Finally, some authors single out the so-called reflex atelectasis. They arise as a result of exposure to various types of irritants on the lung tissue and, in general, on the respiratory system. It can be pain, and impaired mobility of individual parts of the chest wall or diaphragm. This is the inhalation of various irritating or damaging liquids, the aspiration or inhalation of various gases. But the reflex collapse of a part of the lung (as a rule, it is one or more lobules) – rounded atelectases are distinguished here (we will talk about them today) and well-known discoid atelectasis or discoid collapses.

09:32

In fairness, it should be said that many physiologists, pathologists, therapists distinguish between atelectasis and collapse. Most often, atelectasis is understood as a condition of obstruction of a large bronchus, as a result of which partial or complete atelectasis occurs. And collapse – this term denotes the state of the lung tissue, the collapse of the lung tissue, in which the lumen of the corresponding bronchus remains free. Therefore, compression atelectasis and reflex atelectasis are very often referred to in the literature and in clinical practice as collapses.

Finally, in terms of volume, according to the degree of involvement of the lung tissue in this process, these are lobar, segmental, subsegmental, discoid atelectasis, which can be observed during X-ray and anatomical examination.

(Slide show) .

Lung atelectasis. If we talk about the semiotics of this pathological condition, it is very often described in textbooks on radiology, radiology, pulmonology. This is a pathological condition that is associated with airlessness of the whole lung.

It is distinguished by uniform shading of half of the hemothorax. Displacement of the mediastinum – primarily the trachea, which remains visible against the background of the shadow of the mediastinum, airless lung tissue. Lack of bronchial lumen and narrowing of the intercostal spaces. All this gives a general picture of atelectasis, in general, quite understandable, characteristic even with a conventional X-ray examination.

(Slide show) .

As a rule, radiologists in these cases speak of the need for differential diagnosis of this kind of pathological conditions with other causes leading to a decrease in part of the lung. Among them, the most common, of course, is cirrhosis of the lung, when the shadow of the compacted area becomes not entirely uniform.

But still, in most cases, the cause is a neoplasm of the left main bronchus or a neoplasm that involves both lobar bronchus. We clearly see the displaced trachea, the main bronchi, the shadow of the spine, which is visible against the background of the right lung, enlarged in volume. This, of course, is a typical picture of atelectasis of the entire left lung.

11:51

(Slide show) .

The same in the CT image. The atelectosed light lung tissue is clearly visible with areas of swelling inside this lung tissue. The tumor surrounding the pulmonary artery is visible, depicted in a darker color. And also, of course, the stump of the left main bronchus. It, in fact, is the reason for the formation of such a total atelectasis of the whole lung.

Naturally, we always say that such conditions must be differentiated from another pathological condition, typical and characteristic – this is a pleural lunge, which can also create such a total shading of the lung field. The classic differential diagnostic sign here, of course, is the displacement of the mediastinum.

(Slide show) .

In the presence of fluid in the pleural cavity, as a rule, the mediastinum is displaced in the opposite direction. This is clearly seen from the location of the trachea, sometimes from the location of the shadow of the heart, as in this case.

This is an example of two patients who were examined in intensive care. Posterior images of two resuscitation patients clearly show the differences between these two pathological conditions.

(Slide show) .

If we talk about the more common atelectasis, atelectasis of the lobes and segments, then their radiographic signs are also quite well known and described many times. This, of course, is a seal or (in the language of x-ray skiology) shading of the anatomical part of the lung.

The anatomy is very important here. In all cases, we see a clear shading contour that borders on the air-containing lung tissue. This contour, of course, is always formed by the interlobar pleura – an additional or main, oblique interlobar fissure.

This interlobar fissure is always clearly visible on one of the pictures in frontal or lateral projection. Of course, this interlobar fissure is shifted towards the mediastinum up or down, which indicates a decrease in the volume of the affected part of the lung.

We also clearly see the displacement of neighboring anatomical structures towards shading: diaphragm, narrowing of the intercostal spaces, displacement of the mediastinal shadow towards the airless area. Of course, with obstructive atelectasis, most often this is the absence of bronchial lumen or the so-called break or bronchus stump (radiologists call it that) during tomographic examination.

14:17

(Slide show) .

When performing a CT or MRI study, there is again a thickening of the anatomical part of the lung, again a decrease in the volume of the affected part of the lung. But in this case, we, of course, more accurately see the structure of a compacted or airless area. We very well see the expansion of the lumen of the bronchi in the area of ​​atelectasis as a result of the accumulation of bronchial secretions or air in them, depending on the type of pathological changes.

(Slide show) .

Here is a classic picture of atelectasis of the upper lobe of the right lung. The compacted airless upper lobe is wrinkled, reduced in volume, located near the mediastinum. On the reformation in the frontal projection, you see that in the lumen of the right main bronchus there is a pathological formation emanating from the upper lobe bronchus. This leads to the formation of such atelectasis of the entire upper lobe of the right lung.

In lateral view, this is in front of the chest wall. Here is the same thing enlarged.

15:14

(Slide show) .

The structure of the atelectosed part of the lung is clearly visible. In addition to the pathological formation itself, which obturates the lumen of the bronchus, we see smaller subsegmental bronchi expanded and filled with bronchial secretions on axial sections. This is a typical condition, which we define as obstructive atelectasis or obstructive pneumonitis, which is characteristic of such patients.

A few words about the topic, about where and how atelectases are located with several clinical examples.

(Slide show) .

I have already said that atelectosed lung tissue is reduced in volume. This leads to a displacement of the interlobar fissures in a completely regular direction – usually towards the mediastinum. It shows the direction of displacement of the additional interlobar fissure during atelectosis, atelectasis of the upper lobe of the right lung.

(Slide show) .

Another example from the same area. Pathological formation in the projection of the upper lobe bronchus, and the upper lobe of the right lung, reduced in volume and displaced towards the upper mediastinum.

The average share at research in a direct projection does not receive such accurate, clear display. It is rather the disappearance of the right contour of the mediastinum, the median shadow in this area. And in the lateral projection, a triangular, trapezoidal seal is clearly visible. It is located in the projection of the middle lobe, limited by two interlobar fissures, therefore, as a rule, it has a clear concave contour.

(Slide show) .

Here you can see a non-localized seal in the projection of the root of the right lung and in the lateral projection of atelectasis of the middle lobe, which is confirmed by tomography.

(Slide show) .

Classical picture of atelectasis of the lower lobe of the right lung. Horizontal or oblique line that starts from the root of the lung and goes towards the diaphragm in direct projection and the disappearance of the normal contour of the diaphragm. In the lateral projection, this airless part of the lung is located in the projection of the posterior part of the costophrenic sinus.

17:19

(Slide show) .

Standard picture: atelectasis of the lower lobe of the right lung. A typical upper contour of atelectasis that crosses the dome of the diaphragm and an induration that is located against the background of the shadow of the spine in the back of the right lung above the diaphragm.

(Slide show) .

The same in the tomographic image. A relatively small tumor, however, completely overlapping the lumen of the lower lobe bronchus. As a consequence of this, the decrease in volume and complete atelectasis of the lower lobe of the right lung is clearly visible in the upper right picture. The tumor itself, the enlarged lumen of the bronchus of the lower lobe and airless lung tissue in the projection of the posterior part of the costophrenic sinus.

(Slide show) .

Perhaps one of the most difficult clinical situations is atelectasis of the upper lobe of the left lung. In direct projection, we can see only a non-localized decrease in the airiness of the lung tissue in the upper part of the left lung field. And in the lateral projection, a typical picture of lung tissue compaction in the retrosternal space as a result of the displacement of the lobe forward towards the mediastinum.

In this case, the arrows on the image in the lateral projection indicate a reduced in volume, partially airless upper lobe. And on the roentgenogram in a direct projection – a non-localized seal in the region of the apex of the left lung.

(Slide show) .

You can see how different it is from the upper parts of the right lung. And with linear tomography, a pathological formation, a bronchus adenoma, which obturates the lumen of the upper lobe bronchus. He, in fact, leads to such pathological changes.

(Slide show) .

Sometimes, especially in cases where there is an additional interlobar gap, atelectasis of the upper three segments occurs on the left. Their picture is very similar to what is happening in the right lung. Then we see a relatively clear contour of the collapsed upper lobe. In the computed tomography image, the classic image of atelectasis of the upper three segments of the left lung.

(Slide show) .

Finally, atelectasis of the lower lobe of the left lung. The proportion decreases towards the spine, back and towards the mediastinum. From here, naturally, in the lateral projection, it occupies the projection of the posterior part of the costophrenic sinus. And in direct projection, the atelectosed part of the lung is located behind the heart and, one way or another, overlaps the contour of the heart, depending on the volume of the affected part of the lung.

(Slide show) .

In this situation, we can clearly see the contour of the heart and, outside of it, the contour of the interlobar fissure. It limits atelectasis, or a completely collapsed, airless lower lobe of the left lung.

Naturally, in this situation we do not see a clear contour of the left half of the diaphragm, the costophrenic sinus. The collapsed, completely airless lower lobe of the left lung is clearly visible on the computed tomogram.

(Slide show) .

In this case, it occurs as a result of a tumor that completely obstructs the lumen of the lower lobe bronchus and causes such a typical atelectasis of the lower lobe of the left lung.

20:26

Features of the formation of atelectasis

00:00

Igor Evgenyevich Tyurin , professor, doctor of medical sciences:

– Features of the formation of atelectasis.

(Slide show) .

Of course, the mechanism of bronchus obstruction – its further fate depends on it. Why. Because fast, instantaneous (within a few minutes or even seconds, or hours, maybe) complete obstruction of the lumen of the bronchus leads to the formation of atelectasis in the truest sense of the word. Air is resorbed from the alveoli, resulting in areas of airless lung tissue.

The peculiarity lies in the fact that in this case (when a foreign body enters the lumen of the bronchus, and this body, like a plug, completely and immediately clogs the lumen of the bronchus), in this case, distal to the place of narrowing of the obturation in the lung tissue, obstructive pneumonitis does not have time to develop – secondary inflammatory process. As a consequence, such atelectasis can exist for many months, sometimes even years – such observations are described in the literature.

After the cause that caused such instantaneous atelectasis is eliminated (say, a foreign body is removed from the lumen of the bronchus), the lung tissue, paradoxically, straightens out. Restores its airiness and continues to function in the same way as the remaining healthy lung tissue. By the way, this is one of the possible examples of the experimental formation of atelectasis of the lung tissue.

When gradual atelectasis occurs, when this process is extended in time. Especially when it is a partial obstruction of the bronchus, and there is communication between the proximal and distal parts of the respiratory tract. In this case, as a rule, obstructive pneumonitis develops.

It has a number of very important distinguishing features – we will talk about them a little later. But the most important thing is that there are secondary inflammatory processes with corresponding clinical manifestations.

The second very important circumstance: the degree of obturation of the bronchial lumen. Of course, complete obturation of the bronchial lumen should theoretically lead to the same complete atelectasis. However, we very often observe that such a direct relationship does not exist.

We can observe complete bronchus obstruction and airy lung tissue without any signs of atelectasis. This is not some surprising physiological phenomenon, given that the air supply to individual sections of the lung tissue has a very large number of colotherals.

I repeat once again: this does not have any direct relationship. Just as, in fact, there is no strict sequence in the development of atelectasis, as was often described earlier in textbooks. At first it is partial atelectasis or, as it is sometimes called, hypoventilation. Then this so-called obstructive swelling, then complete atelectasis.

Very often we observe a mixture of different stages, degrees of bronchial obstruction. Therefore, we are more interested in the state of the lung tissue right now.

03:05

(Slide show) .

What is the peculiarity of obstructive pneumonitis. Occurs with a partial violation of bronchial patency. It is characterized by a combination of atelectasis, chronic inflammation, pneumosclerosis.

These three processes keep the lung tissue reduced in volume in a collapsed state and prevent it from expanding. But, most importantly, after the restoration of bronchial patency, as a rule, there is no restoration of the airiness of the lung tissue due to the development of a chronic inflammatory process, distelectasis, emphysema, and pneumosclerosis there. And the degree of airiness can really change, but only slightly.

This is the most important reason, which often complicates the diagnosis of such conditions, when a patient with obstructive atelectasis in the presence of central cancer is subjected to antibiotic therapy. The condition improves somewhat, the airiness of the lung tissue is somewhat restored, but not completely – and then this process continues to exist and does not lead to a positive result.

(Slide show) .

Here is one of these possible variants of obstructive pneumonitis. Infiltrative changes that are localized, in this case, in the upper lobe of the right lung – they are formally completely indistinguishable from upper lobe pneumonia. But the problem is that obstructive pneumonitis itself, despite the ongoing treatment, rarely undergoes a complete regression.

When we observe this patient in dynamics, we see that the changes in the lung tissue remain, but the cause that causes such a secondary inflammatory process has become very clearly visible. In this patient, of course, this is a large pathological formation, which is located at the root of the right lung, in the projection of the upper lobe bronchus. Narrows this bronchus and causes such a continuously recurrent process in the lung tissue.

04:51

(Slide show) .

If we are talking about obstructive pneumonitis, of course, computed tomography and tomography in general are of fundamental importance here. In the case of a decrease in the volume of a part of the lung, as in this patient – and here it is quite obvious a decrease in the volume of the upper lobe of the right lung, uneven compaction of the upper lobe. But with a tomographic study, we see preserved lobar segmental bronchi. This makes it possible to distinguish such a decrease in the volume of the upper lobe during an inflammatory process (in this case, it is prolonged pneumonia) from obstructive pneumonitis resulting from compression or narrowing of the large bronchi.

(Slide show) .

Diagnostic tactics in such cases. We see a protracted course of pneumonia or, moreover, a recurrent course of pneumonia. An x-ray examination determines a pronounced decrease in the volume of a lobe or segment and this does not tend to recover, especially in combination with an expansion of the lung root.

Of course, in this case, bronchological examination and computed tomography are absolutely essential to assess the condition of the lobar and segmental bronchi.

(Slide show) .

And also what I have already said about the violation of bronchial patency and the degree of collapse of the lung tissue. In this case, you see almost complete obturation of the third segmental bronchus. The second segmental bronchus is in place, it is clearly visible – heading backwards. And in front of the stump is a square shape due to the endobronchial formation of the third segmental bronchus, which completely covers the lumen of this bronchus.

However, the lung tissue retains its airiness, and neither radiographs nor CT scans show any signs of atelectasis here. This situation does not arise very often, of course, but there is nothing extraordinary in it. This is a common physiological mechanism for compensatory ventilation of individual sections of the lung.

If we talk about the causes of atelectasis and our ability to distinguish between these causes in some way using the methods of radiation diagnostics, they are here in front of you on the slide.

06:55

(Slide show) .

Of course, the most common are neoplasms. Malignant, much less often benign, tumors. In addition, cicatricial structure, post-tuberculosis, post-traumatic foreign bodies. Including bronchiolitis that occurs in patients who have had pulmonary tuberculosis.

This is compression of the bronchus from the outside. Usually this is either mediastinal lymph nodes, or (when it comes to the lower lobe of the left lung) compacted dilated aorta. Then there is atelectasis of the lower lobe of the left lung – but this is a rarer cause.

Of course, the most common are neoplasms. I will not return to the usual neoplasms that we often encounter in our practice. Almost all the examples of atelectasis that I have just shown, one way or another, were associated with primary tumors of the central bronchi (central cancer) and the formation of the corresponding atelectasis. What I want to show now is our capabilities and our limitations in terms of diagnostics.

(Slide show) .

Can we somehow determine the morphological structure of the pathological formation that closes the lumen of the bronchus and leads to the development of atelectasis. Unfortunately, in most cases, no. Therefore, the common conclusion of radiologists, when they see atelectasis and stenosis of the bronchus, that it is lung cancer, is formally untrue.

Cancer is, after all, an epithelial tumor originating from the surface of the bronchial tree. It’s still a morphological diagnosis. However, bronchoconstriction itself can develop as a result of many other causes.

In a number of cases, we can very well find this reason, see it. One of the rare observations, but, as usual, showing the possibilities of radiation diagnostics. The classic picture of atelectasis of the middle lobe of the right lung. Non-localized shadowing in the right cardiodiaphragmatic angle and a typical triangular shadow in the projection of the middle lobe in the image in the lateral projection.

08:55

(Slide show) .

What do we see with computed tomography. A fat-containing pathological formation that completely blocks the lumen of the middle lobe bronchus. In this case, of course, the radiologist can practically establish a morphological diagnosis by simply analyzing computed tomography images.

(Slide show) .

Naturally, in such cases it is possible to obtain a more beautiful image using, for example, virtual bronchoscopy, as in this case. Make sure that this is really a stenosis of a large bronchus, this is a pathological formation. But the main thing is that in this situation we can see the very reason and actually determine the morphological character.

(Slide show) .

Another possible situation where we understand well what is at stake is carcinoids. These are neuroendocrine tumors, some of which have an exceptionally high blood supply. They behave like hypervascular structures in tomographic examination, with the introduction of contrast agents, and in angiographic studies.

In this situation, the digital radiograph shows the classic picture of atelectasis of the lower lobe of the left lung. In this case, the contour of the dormant left lobe is located inside the contour of the heart. Naturally, the normal image of the dome of the diaphragm, the costophrenic sinus, disappears. And in a tomographic study – a rounded shape with clear contours, a hypervascular formation in the root of the left lung and a typical atelectasis of the lower lobe of the left lung with dilated bronchi.

(Slide show) .

I repeat once again: carcinoid. In this situation, of course, the radiologist can quite accurately suggest, at least, the morphological nature of the changes in the chest cavity.

10:33

(Slide show) .

On the other hand, there are situations when we are completely deprived of such an opportunity. I have already said that most often, of course, this malignant tumor is a cancerous tumor.

(Slide show) .

Metastases in the large bronchi are less common. But if they occur, then the x-ray picture in patients who have had breast cancer, colon cancer, kidney cancer, melanoma, is practically indistinguishable from the x-ray picture of primary lung cancer.

(Slide show) .

In this case, we observe a picture of the formation of complete atelectasis of the upper lobe of the left lung over several months (here it is well shown by arrows).

(Slide show) .

On tomographic examination, a huge pathological formation, almost completely obstructing the lumen of the left main bronchus. At the same time, this is rectal cancer, metastasis to the left upper lobe bronchus. This is morphologically proven. Not every atelectasis with not every malignant formation is a cancerous tumor.

A few words about benign structures and the formation of obstructive atelectasis with such changes.

(Slide show) .

Cicatricial structures, foreign bodies of the bronchi, compression from the outside – these are quite common situations. In this case, of course, the formal picture of atelectasis should be accompanied by additional tomographic studies.

11:55

(Slide show) .

Why. Of course, one of the very common causes in this situation is tuberculosis. Or it is obturation with bronchodilitis. Or it is compression of the bronchi by enlarged lymph nodes. Or these are the consequences of tuberculosis, as in this case.

The narrowed lumen of the middle lobe bronchus is surrounded by partially calcified lymph nodes after tuberculosis. This is a classic middle lobe syndrome as a result of previous primary pulmonary tuberculosis. It is very important that in this case the radiologist has the opportunity to determine the correct topic of these changes and their cause.

(Slide show) .

And on the other hand, this is the loss of caseous-necrotic calcified masses from the lymph node. Broncholiths that enter the large bronchi obturate them. The result is atelectasis of the reed segments. We clearly see this radiopaque foreign body (in this case, broncholitis) directly in the lumen of the lingual segmental bronchus. This, of course, distinguishes such obstructive atelectasis from malignant tumors.

(Slide show) .

As well as with more advanced technical support, when we have multislice computed tomography at our disposal, the broncholitis is perfectly visible here, which is located in the bronchus of the anterior segment (in the third segmental bronchus). It obturates the lumen of this bronchus, but again (note) does not cause the formation of atelectasis, but only a decrease in volume.

(Slide show) .

Of course, the classics of the genre are bronchial foreign bodies. Especially in children, as in this case. This is a chicken bone that obturates the lumen of the lower lobe bronchus. In this case, of course, the radiopaque foreign body (bone) is clearly visible in X-ray tomography. It is well understood what it is.

Difficulties arise in situations where these are not contrasting foreign bodies. Then it is very difficult to distinguish them from neoplasms and other causes that cause compression of the bronchi.

Compression of the bronchi by enlarged lymph nodes, which is observed in malignant tumors, with metastatic lesions of the lymph nodes.

(Slide show) .

In this case, an example of a classic upper lobe atelectasis in a child suffering from tuberculosis of the intrathoracic lymph nodes. In the picture in the lower right corner, you can clearly see the enlarged lymph nodes in the root of the right lung.

14:08

(Slide show) .

Finally, fibroatelectasis. A peculiar pathological condition that occurs as a result of the transferred inflammatory process. X-ray signs of atelectasis in this case are combined with the preservation of the lumen of a large bronchus. In fact, this is a pathological condition that combines signs of both fibrotic changes in the lung tissue and signs of atelectasis.

(Slide show) .

It is fundamentally important to determine and prove that the decrease in the volume of a part of the lung is not associated with a neoplasm, but is based on an inflammatory process.

(Slide show) .

Here, of course, a tomographic study, along with a bronchological one, allows you to very accurately assess the condition of the lobar and segmental bronchi and, on this basis, exclude the presence of a pathological formation.

(Slide show) .

Another very important element of bronchial obstruction or atelectasis, types of atelectasis, is the so-called round atelectasis. I will not show discoid atelectasis today – I think everyone knows this well and understands how it looks. But I will show a peculiar kind of lung tissue pathologies, a kind of reflex atelectasis. They arise, I repeat once again, due to various irritating factors.

Typical CT (sometimes even x-ray) picture. It is associated with the formation of a site of compaction in the lung tissue and a very characteristic change in the vascular bronchial pattern in the lung tissue, like a comet’s tail directed from the root of the lung. You see it on CT scans.

(Slide show) .

It looks like this on a plain radiograph – as segmental or subsegmental atelectasis. And with a tomographic study, as I said, this is a fairly characteristic picture.

15:49

(Slide show) .

In conclusion, a few words about retention cysts. Occurs with obstruction of the bronchi of medium caliber. As a rule, these are still the bronchi distal to the subsegmental ones.

Usually this is the result of bronchial tuberculosis, we say, and first of all we look for post-tuberculosis changes in such patients. Although retention cysts or bronchial dilation as a result of the accumulation there of an excessive amount of bronchial secretions can be observed in many other pathological conditions. Where there is a violation of the discharge of bronchial secretions through the bronchi.

It can also be bronchial atresia as a congenital pathology. These are bronchiectasis with the formation of retention cysts. For example, with bronchial asthma, with allergic bronchopulmonary aspergillosis and a number of other pathological processes. Including, as you have just seen, with obstructive atelectasis, such dilated bronchi are formally formed in the form of retention cysts inside the atelectotic lung tissue.

They usually have a typical V- or Y-shape, with the tip towards the root of the lung and the base towards the visceral pleura. Sometimes they contain calcifications (calcified contents, calcified bronchial wall) – then this is a very important criterion in terms of a tuberculosis history in such a patient. And they can also have a liquid density on computed tomography – then this, of course, facilitates the diagnosis.

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Classical picture: an irregularly shaped pathological formation that has a V-shape with two branches, the tip facing the draining bronchus. A tomographic examination clearly shows calcium inclusions in one of the walls of this pathological formation.

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Another example, when the content of the retention cyst itself is subjected to calcification. On the radiograph in the lateral projection, a V-shaped large structure is perfectly visible in the anterior part of the right lung, consisting of two horns, with a tip facing the root of the lung. This is clearly seen in the tomographic examination.

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There is a huge calcified paratrachial lymph node at the root of the lung, complete obstruction of the subsegmental bronchus of the third segment. As well as partially calcified caseous contents of this retention cyst, which is located in the third bronchopulmonary segment.

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But still, more often we see not such large retention cysts, but smaller formations. This is important, because in this situation, of course, we are talking about differential diagnosis with peripheral formations in the lungs.