Overview
Definition:
Segmentectomy of the left upper division (LUD) is a surgical procedure involving the removal of the superior segment of the left upper lobe of the lung
This lobar subdivision represents a distinct anatomical and bronchopulmonary segment
It is a form of lung-sparing surgery, preserving more lung parenchyma compared to a standard lobectomy.
Epidemiology:
The incidence of LUD segmentectomy is dictated by the prevalence of lung pathologies localized to this specific segment, such as small solitary pulmonary nodules, early-stage lung cancers, or specific granulomatous diseases
It is more commonly performed in patients with compromised pulmonary function where maximal lung preservation is desired.
Clinical Significance:
LUD segmentectomy is crucial for oncological control of small, peripheral lung cancers confined to this segment, offering a survival benefit comparable to lobectomy in select cases while minimizing postoperative pulmonary dysfunction
For benign conditions, it provides definitive treatment with less morbidity
This procedure highlights the importance of precise anatomical knowledge for effective surgical planning and execution, a critical skill for DNB and NEET SS candidates.
Indications
Oncological Indications:
Primary lung adenocarcinomas (T1N0M0) ≤ 2 cm, especially ground-glass nodules or small solid nodules with lepidic predominance
Metastatic nodules to the LUD segment
Recurrent or new primary lung cancers in patients with limited pulmonary reserve who cannot tolerate lobectomy
Peripheral non-small cell lung cancer (NSCLC) with no nodal involvement.
Benign Indications:
Recurrent or complicated infections (e.g., tuberculosis, fungal infections) localized to the LUD segment
Benign tumors or hamartomas
Arteriovenous malformations or congenital lung abnormalities in the LUD
Bronchiectasis confined to the LUD segment.
Patient Selection Criteria:
Patients must have a solitary or limited number of lesions confined to the LUD segment with clear margins achievable
Preoperative staging must exclude nodal involvement or distant metastases for oncological indications
Patients should be evaluated for their ability to tolerate general anesthesia and thoracic surgery
Pulmonary function tests (PFTs) are essential, and patients with severely compromised lung function may be prioritized for segmentectomy over lobectomy.
Preoperative Preparation
Diagnostic Workup:
Comprehensive history and physical examination
Chest X-ray and contrast-enhanced CT scan of the chest for lesion characterization and staging
PET-CT scan for nodal staging and distant metastasis evaluation
Bronchoscopy with biopsy if centrally located or suspicious for endobronchial involvement
CT angiography or MRI may be used to delineate vascular and bronchial anatomy.
Pulmonary Function Tests:
Forced expiratory volume in 1 second (FEV1) and diffusion capacity of the lung for carbon monoxide (DLCO) are crucial
Predicted postoperative FEV1 and DLCO calculations are performed to assess the impact of resection
A predicted postoperative FEV1 > 40% of predicted is generally considered safe for segmentectomy.
Patient Counseling And Optimization:
Detailed discussion of the procedure, risks, benefits, and alternatives
Smoking cessation counseling is mandatory
Nutritional optimization and physiotherapy may be recommended
Antibiotic prophylaxis is typically administered preoperatively.
Procedure Steps
Surgical Approach:
Video-assisted thoracoscopic surgery (VATS) is the preferred approach for its minimally invasive nature, reduced pain, and faster recovery
Open thoracotomy may be necessary for extensive disease or in specific anatomical challenges.
Anatomical Dissection And Identification:
Precise identification of the segmental bronchus, artery, and vein supplying the LUD segment is paramount
This requires meticulous dissection along anatomical planes
The LUD is the superior-most segment of the left upper lobe.
Segmental Vascular And Bronchial Control:
The LUD artery and vein are identified and divided
The LUD bronchus is then isolated and stapled or divided
Careful attention is paid to avoid injury to adjacent segments or pulmonary vessels
Techniques for stapling and dividing segmental structures, often using endoscopic stapling devices, are critical.
Parenchymal Transection:
The boundary for resection is typically marked along the intersegmental lung surface
The lung parenchyma is then divided using an energy device or stapler, ensuring hemostasis and air-tight closure
Indocyanine green (ICG) fluorescence imaging can aid in visualizing segmental boundaries and perfusion.
Specimen Handling And Margins:
The resected specimen is examined for completeness and sent for histopathological analysis
Intraoperative frozen section analysis may be performed to confirm negative margins, especially in oncological cases
The entire segment and any surrounding suspicious tissue are removed.
Postoperative Care
Monitoring:
Close monitoring of vital signs, oxygen saturation, chest tube drainage, and pain levels
Early mobilization and incentive spirometry are encouraged
Pulmonary toilet and chest physiotherapy are important.
Pain Management:
Multimodal pain management, including epidural analgesia, patient-controlled analgesia (PCA), and oral analgesics, is essential for comfort and facilitating deep breathing exercises.
Chest Tube Management:
Chest tubes are typically placed for pleural drainage
Management involves monitoring drainage volume and air leaks
Early removal of chest tubes is often possible if drainage is minimal and no air leak is present.
Complication Surveillance:
Vigilance for complications such as pneumothorax, hemothorax, pneumonia, prolonged air leak, chylothorax, and atelectasis
Early recognition and management are key.
Complications
Early Complications:
Prolonged air leak (>5 days)
Postoperative bleeding requiring re-exploration
Pneumonia
Atelectasis
Persistent pleural effusion
Respiratory failure in patients with compromised pulmonary function.
Late Complications:
Bronchopleural fistula (rare)
Scarring and fibrosis
Chronic pain
Development of new nodules in remaining lung segments
Recurrence of primary disease if margins were inadequate or nodal disease was present but undetected.
Prevention Strategies:
Meticulous surgical technique with precise anatomical dissection
Adequate stapling of bronchus and vessels
Careful parenchymal transection with adequate sealing
Intraoperative assessment of margins
Aggressive pulmonary toilet and early mobilization
Smoking cessation
Appropriate antibiotic prophylaxis.
Prognosis
Factors Affecting Prognosis:
For oncological indications, the stage of the disease, histological subtype, and margin status are primary prognostic factors
For benign conditions, the underlying pathology and extent of resection influence outcomes
Preoperative pulmonary function is also a significant predictor of long-term respiratory health.
Outcomes:
For early-stage lung cancer, segmentectomy can achieve oncological outcomes comparable to lobectomy with less functional impairment
For benign conditions, resolution of symptoms and prevention of recurrence are expected
Patients generally experience better quality of life and improved exercise tolerance compared to lobectomy.
Follow Up:
Regular follow-up with chest imaging (CT scans) is recommended, especially for oncological patients, to detect recurrence or new primary lung cancers
Frequency and duration of follow-up are guided by oncological guidelines
For benign conditions, follow-up is typically based on symptom resolution and clinician judgment.
Key Points
Exam Focus:
Understanding the precise anatomical boundaries of the left upper division
Differentiating segmentectomy from lobectomy and wedge resection indications
Knowledge of VATS vs
open approach
Recognition of potential complications and their management.
Clinical Pearls:
Always confirm segmental vascular and bronchial anatomy before division
Use ICG fluorescence to aid visualization of segmental boundaries and perfusion
Careful hemostasis and air sealing are paramount
Consider pulmonary reserve when selecting between segmentectomy and lobectomy
Intraoperative frozen sections are critical for margin assessment in malignancy.
Common Mistakes:
Inadequate oncological staging leading to incomplete resection
Injury to adjacent pulmonary vessels or bronchi
Failure to achieve clear surgical margins
Undertreating or overtreating benign lesions
Insufficient attention to postoperative pulmonary physiotherapy.