SSCTS

(Henrietta Wilson¹)

A Lobectomy is an operation in which the entire lobe of a lung is removed.

Indications

There are numerous indications for pulmonary lobectomy; these can be classified as benign or malignant.

Pulmonary Anatomy

To understand this surgical procedure we need a basic knowledge of the anatomy involved.

The Lungs:

• The right lung is larger than the left (ratio of 55% to 45%)

• The left lung has 2 lobes (upper with lingular segment and lower) divided by the oblique fissure while the right is made up of 3 lobes (upper, middle and lower) divided by the oblique and transverse fissures.

• The hilum of the lung is a triangular depression on the mediastinal surface of each lung. It consists of the pulmonary vessels, bronchi, bronchial arteries and lymph nodes.

The Posterior Chest Wall:

• Superficial muscles: Trapezius and lattissimus dorsi

• Deep muscles: Serratus anterior and the rhomboids

• Intercostals: External, internal and innermost groups

Pre-Operative

·         Imaging will most likely take the form of a CXR in addition to a CT and/or positron emission tomography scan. These modalities are used to plan the resection and assess postoperative predicted lung function

·         Pulmonary function tests are used to predict the patient’s postoperative lung function following lobectomy

·         If lobectomy is for malignant disease further investigations such as CT head may be required to stage the disease.

Incisions

The patient is positioned in the lateral decubitus position to allow the best surgical access. A double-lumen endotracheal tube is placed to allow deflation of the diseased lung while continuing ventilation of the other.

Posterolateral thoracotomy is the incision most commonly used for open lobectomy. The incision is centred around the tip of the scapula.

• Three major muscles encountered are the trapezius, latissimus dorsi and serratus anterior.

• This is a curvilinear incision from the anterior axillary line passing 3-4cm below the tip of the scapula and continuing superiorly midway between the medial border of the scapula and vertebral column.

An alternative to open thoracotomy is video assisted thoracic surgery. This is a minimally invasive option that can be used in benign pulmonary disease and in selected early-stage malignant cases.

Post-operative considerations

Pain relief

• This is an extremely important aspect of post-operative care with good control leading to better outcomes.

• Pain relief is usually achieved with a combination of regional block (epidural or paravertebral catheter) and patient controlled analgesia (PCA).

Thromboembolic prophylaxis

·         All thoracotomy patients require prophylaxis usually in the form of TEDs stockings and low-molecular weight heparin.

Chest drains

• Post lobectomy patients will have two chest drains in situ. The position of the drains is an anterior drain positioned apically and a posterior drain positioned basally.

 

Complications

The complications of lobectomy can be classified as general and specific.

 

General complications include wound infection, pulmonary embolism or deep vein thrombosis and atelectasis, and death. The mortality rate is 1-3%; the major causes being septic complications and post-operative cardiopulmonary insufficiency.

 

Specific complications:

• Injury to a large vessel (pulmonary artery or vein) leading to massive bleeding or haemothorax post-operatively.

• Cardiac dysrhythmia is frequently seen intra-operatively with atrial fibrillation being the most common abnormality.

• Persistent air leak seen as ongoing pneumothorax and bubbling from chest drain.

• Empyema or pneumonia

• Bronchopleural fistula: a communication between the bronchial stump and pleural cavity leading to a persistent air leak and increased risk of infection. Seen in 1-4% of patients post lobectomy.

 

Other less common problems include oesophageal damage, chylothorax secondary to thoracic duct injury, and damage to thoracic nerves (phrenic or recurrent laryngeal nerves).

 

 

References

·         Oxford Handbook of Cardiothoracic Surgery. Chikwe, Beddow, Glenville, 2006

·         Stephan F et al. Pulmonary Complications Following Lung Resection. A Comprehensive Analysis of Incidence and Possible Risk Factors. Chest Nov 2000;118 (5): 1263 – 70

 

 

Posted 20th March 2010

 

1- Henrietta Wilson - SHO in Cardiothoracic Surgery, London.