Overview
Definition:
Pneumonectomy is a surgical procedure involving the removal of an entire lung
It is typically performed for conditions affecting the entire lung, most commonly malignant lung tumors that are unresectable by less extensive lung resections, and less frequently for severe, unilateral destructive lung diseases or infections.
Epidemiology:
Pneumonectomy rates have decreased over time due to advances in early lung cancer detection and minimally invasive techniques like lobectomy and segmentectomy
However, it remains a crucial intervention for selected patients, with lung cancer being the primary indication
The incidence varies geographically and is strongly associated with smoking prevalence.
Clinical Significance:
Pneumonectomy is a major surgical undertaking with significant physiological consequences, primarily due to the loss of 50% of lung function
It is reserved for cases where less radical surgery is not feasible, making it a critical procedure for salvaging life in advanced lung disease or cancer
Understanding its indications, risks, and management is vital for surgical residents preparing for DNB and NEET SS examinations.
Indications
Surgical Indications:
Primary indication is non-small cell lung cancer (NSCLC) involving the entire lung, hilar structures, or extending to the mediastinum, when lobectomy or pneumonectomy is not technically feasible or oncologically adequate
Other indications include severe, unilateral, debilitating lung diseases such as tuberculosis (e.g., unilateral fibrocavernous TB), bronchiectasis, fungal infections (e.g., aspergilloma), bullous emphysema affecting the entire lung, congenital lung abnormalities, and severe unilateral empyema with bronchopleural fistula
For lung cancer, suitability depends on tumor stage, patient's cardiopulmonary reserve, and absence of distant metastases.
Patient Selection:
Careful patient selection is paramount
This includes thorough cardiopulmonary assessment to determine if the patient can tolerate the loss of an entire lung
Forced expiratory volume in 1 second (FEV1) and diffusing capacity of the lungs for carbon monoxide (DLCO) are critical parameters
Post-pneumonectomy FEV1 and DLCO should ideally be >40% and >40% of predicted values, respectively
Cardiopulmonary exercise testing may be required for borderline candidates.
Relative Contraindications:
Significant bilateral lung disease
Severe pulmonary hypertension
Inoperable contralateral lung disease
Poor overall health status and performance status (ECOG > 2)
Presence of distant metastases for malignant disease
Acute infection of the remaining lung
Myocardial infarction within the past 6 months
Uncontrolled arrhythmias
Impaired renal function.
Preoperative Preparation
Diagnostic Workup:
Comprehensive workup includes detailed history and physical examination, chest X-ray, CT scan of the chest with contrast, PET-CT scan for staging lung cancer, bronchoscopy, sputum cytology, pulmonary function tests (PFTs) including spirometry, DLCO, arterial blood gas (ABG) analysis, and electrocardiogram (ECG)
Echocardiography may be performed to assess cardiac function and pulmonary artery pressures
Cardiopulmonary exercise testing (CPET) is essential for risk stratification.
Patient Optimization:
Smoking cessation at least 4-8 weeks prior to surgery
Nutritional support and counseling for weight maintenance
Physical therapy and breathing exercises to improve pulmonary mechanics
Management of comorbidities like COPD, hypertension, and diabetes
Antibiotic prophylaxis according to institutional guidelines.
Surgical Planning:
Decision between open thoracotomy and video-assisted thoracic surgery (VATS) pneumonectomy, though VATS is less common for complete pneumonectomy due to technical complexity
Planning for chest tube placement and airway management
Discussion of surgical risks and expected outcomes with the patient and family.
Procedure Steps
Surgical Approach:
Typically performed via posterolateral thoracotomy, though VATS may be used in select centers
The patient is placed in the lateral decubitus position
A double-lumen endotracheal tube is used for single-lung ventilation.
Lung Mobilization And Dissection:
The chest cavity is entered, and the lung is meticulously dissected from the parietal pleura
The pulmonary artery, veins, and bronchus are identified and sequentially ligated and divided
The dissection proceeds to the hilum, carefully separating the structures.
Vascular And Bronchial Control:
The pulmonary artery is usually ligated and divided first, followed by the pulmonary veins
The mainstem bronchus is then divided as proximally as possible, typically after division of the vascular structures, using staplers or sutures for secure closure.
Completion And Drainage:
The resected lung is removed from the chest cavity
Hemostasis is ensured
One or two chest tubes are placed in the pleural space for drainage
The chest incision is closed in layers.
Postoperative Care
Immediate Postoperative Management:
Intensive care unit (ICU) monitoring is essential
Pain management with patient-controlled analgesia (PCA) or epidural analgesia
Respiratory support, including supplemental oxygen, incentive spirometry, and chest physiotherapy
Vigilant monitoring of vital signs, fluid balance, and chest tube output.
Respiratory Management:
Early ambulation
Deep breathing exercises and pulmonary rehabilitation
Management of secretions
Monitoring for air leak and atelectasis
Careful weaning from mechanical ventilation if required
Bronchodilators and mucolytics as needed.
Chest Tube Management:
Monitoring of drainage volume and character
Chest X-rays to assess lung expansion and pleural fluid
Chest tubes are typically removed when drainage is minimal and the lung is fully expanded, and there is no air leak.
Pain Control And Mobility:
Adequate pain relief is crucial for deep breathing and mobilization
Early ambulation to prevent deep vein thrombosis (DVT) and pulmonary embolism (PE)
Physical therapy to regain strength and endurance.
Complications
Early Complications:
Common early complications include prolonged air leak (most frequent, can be up to 7-10 days), empyema, bronchopleural fistula (BPF), pneumonia, acute respiratory distress syndrome (ARDS), cardiac arrhythmias (especially atrial fibrillation), pulmonary embolism, deep vein thrombosis, bleeding, and wound infection
Cardiac complications like myocardial infarction and stroke are also possible.
Late Complications:
Chronic pain syndrome, incisional hernia, residual pleural effusion or fibrosis, persistent cough, diaphragm dysfunction (elevation), paradoxical chest wall movement, and psychosocial adjustment issues
Bronchial stump dehiscence, though rare, is a severe late complication.
Prevention Strategies:
Meticulous surgical technique, especially secure bronchial stump closure
Thorough preoperative cardiopulmonary assessment and optimization
Aggressive chest physiotherapy and pulmonary rehabilitation
Early mobilization
Prophylactic antibiotics
Adequate pain control
Careful monitoring of chest tube output and lung expansion
Strict adherence to smoking cessation protocols.
Prognosis
Factors Affecting Prognosis:
Prognosis is largely dependent on the underlying pathology (especially malignancy stage), the patient's cardiopulmonary reserve, presence of comorbidities, and the occurrence of postoperative complications
For lung cancer, stage at diagnosis is the most significant prognostic factor
For benign conditions, prognosis is generally better if the remaining lung can compensate.
Outcomes:
Short-term survival rates for pneumonectomy are improving with better surgical techniques and critical care
Long-term survival for lung cancer patients depends heavily on the stage
Patients who survive the immediate postoperative period and undergo rehabilitation can achieve a reasonable quality of life, though with reduced exercise tolerance
For benign conditions, pneumonectomy can be curative.
Follow Up:
Regular follow-up is essential
This includes clinical assessment, pulmonary function tests, and imaging (chest X-ray, CT scan) at regular intervals
For cancer patients, follow-up focuses on monitoring for recurrence and managing treatment-related side effects
For benign conditions, follow-up assesses for residual disease and monitors the function of the remaining lung.
Key Points
Exam Focus:
Pneumonectomy is the removal of an entire lung
Indications are primarily advanced lung cancer or severe unilateral lung disease
Cardiopulmonary reserve assessment (FEV1, DLCO) is crucial for patient selection
Complications like prolonged air leak and bronchopleural fistula are critical to manage
Postoperative care focuses on respiratory support and early mobilization.
Clinical Pearls:
Always consider the physiological impact of losing half the lung capacity
Optimize the patient pre-operatively to minimize risks
Bronchial stump closure is a critical technical step to prevent BPF
Aggressive pulmonary physiotherapy and early ambulation are cornerstones of recovery.
Common Mistakes:
Inadequate preoperative assessment leading to poor outcomes
Underestimation of the physiological burden
Incomplete mediastinal lymph node dissection in malignant cases
Delayed recognition and management of air leaks or BPF
Insufficient postoperative respiratory support.