FRCA Notes

Lung Resection Surgery

Pneumonectomy, lobectomy and other lung resections fall under the curriculum item: 'describes commonly performed thoracic surgical procedures and the relevant anaesthetic problems'.

It was the subject of an SAQ in 2018 (58% pass rate), with examiners commending answers to questions on one-lung ventilation.

Examiners lambasted performance on a similar CRQ in 2021 (48% pass rate), particular the answers given on relevant physiology and the contraindications to pneumonectomy.

Resources

  • Lung resection surgery takes various forms;
    • Pneumonectomy (4%) i.e. entire lung removal
    • (Bi)lobectomy or lobectomy (77%) i.e. removing two of the three right lung lobes, or a single lobe from either lung
    • Sub-lobar incisions (19%)
      • Segmentectomy
      • Wedge resection
  • This page focuses primarily on pneumonectomy, which is mostly performed as an open procedure (~90%)
  • The majority (56%) of non-pneumonectomy resections are performed using VATS
  • The most common indication is bronchial carcinoma, where the anatomical location of the tumour is not amenable to alternative resection:
    • Main stem bronchus tumours
    • Tumours proximal to the bronchus intermedius
    • Tumours with hilar involvement

  • Non-malignant disease which may require pneumonectomy includes:
    • Traumatic lung injury with uncontrolled haemorrhage
    • Chronic bacterial disorders of the lung e.g. TB
    • Fungal lung infections causing lung destruction

  • Both mortality and QoL are poorer after pneumonectomy compared to lobectomy, bilobectomy or sleeve lobectomy:

    • Survival timeframe Pneumonectomy Lobectomies
    30-day 92.3% 98.5%
    90-day 88.4% 96.8%
    1-year 74.6% 89%

  • Post-operative mortality is strongly linked with increasing age, which is thought to be due to the older RV being unable to cope with the increased PVR post-resection

  • Right pneumonectomy is associated with higher mortality than left
    • Diversion of cardiac output through smaller left lung increases PVR and RV failure
    • Higher incidence of bronchopleural fistula

  • Standard pneumonectomy: most common
    • Affected lung removed with safe bronchial margin and closure of bronchial stump
    • Pulmonary artery and veins are isolated and ligated

  • Intra-pericardial pneumonectomy
    • E.g. if there is involvement of the right or left main pulmonary artery, or the pulmonary vein close to origin from the atria

  • Extra-pleural pneumonectomy
    • A radical resection for mesothelioma
    • Resection of affected lung, ipsilateral pleura, hemidiaphragm and hemi-pericardium
    • MaRS trial: worse mortality than medical management

  • Completion pneumonectomy
    • Follows prior partial resection of lung tissue

  • Carinal pneumonectomy of the lung and carina in patients with carinal/distal tracheal tumours

Perioperative management of the patient undergoing pneumonectomy


Staging

  • Lung cancers are either non-small-cell (85%) or small-cell tumours
  • Non-small-cell tumours are either adeno-, squamous-cell or large-cell carcinomas

  • Patients should have CT and PET-CT scanning to assess lymph node status
    • Positive mediastinal lymph nodes require further sampling e.g. EBUS or mediastinoscopy

  • Surgical options depend on stage:
    • Up to T3N1M0 → radical surgical management
    • T4 and/or N2 disease → MDT-determined management which can include surgery

Suitability for surgery

  • This is largely covered in the page on pre-operative care in thoracic surgery
  • In short:
    1. Assess operative mortality risk using measures of functional capacity (e.g. CPET) and scoring systems such as the Thoracoscore

    2. Assess risk of perioperative cardiac events, with:
      • Risk scoring as per the Revised Cardiac Risk Index
      • Transthoracic echocardiography; pulmonary hypertension is a contraindication to pneumonectomy
      • Cardiology input

    3. Assess risk of post-operative dyspnoea with spirometry, using both absolute values and predicted post-operative values

Optimisation prior to surgery

  • Smoking cessation
  • Optimise comorbidities associated with poor outcomes such as:
    • COPD - respiratory team input and consideration of pulmonary rehabilitation
    • Cardiovascular disease - cardiology input
    • Low body weight or hypoalbuminaemia - dietician input

Surgical technique

  • Post-induction, pre-operative rigid bronchoscopy will establish whether there is sufficient length of bronchus free of tumour to proceed

  • If so, the most common approach is via a postero-lateral thoracotomy at the 5th intercostal space
    • May require removal of the 5th rib

  • The lung is resected down to the anterior hilum
    • Superior and inferior pulmonary veins, and pulmonary artery, are sequentially ligated and divided
    • The bronchus is stapled and cut, ensuring no part of the DLT or other catheters are in the staple line
    • The patency of stump closure is established using a leak test

Monitoring and access

  • AAGBI
  • Arterial line
  • Central venous access; early vasopressors to limit fluid use
  • Temperature probe
  • Urinary catheter

  • Invasive cardiac output monitoring is not validated due to the open thorax

Anaesthetic conduct

Haemodynamic management

  • Ensure two units cross-matched pre-operatively

  • Clamping of the pulmonary artery of the resected lung causes the entire pulmonary circulating volume to pass through the remaining lung
  • Significant cardiovascular collapse or excessive CVP rise at this point indicates insufficient RV compliance
    • It indicates a high likelihood of post-operative cardiac complications and mortality
    • If significant, repeat instability occurs with other contributing factors eliminated, the decision as to whether to proceed should be taken

  • Fluid management should be judicious; avoiding excess fluids whilst also avoiding hypovolaemia and AKI
  • Excessive intra- and post-operative fluid administration is associated with an increased risk of post-operative pulmonary oedema and respiratory failure
  • Restricting patients to 13-20ml/kg total fluids in the first 24hrs is recommended
    • Can be matched to UO + 20ml/hr

Care bundle

  • Antibiotics as per local guidelines
  • Fastidious checking of pressure points; lateral decubitus position with table break
  • VTE prophylaxis
  • Temperature management as standard

Drain management

  • Drain clamped at the end of surgery
  • Clamp removed for 1min every hour to assess for haemorrhage
  • If the drain is unclamped for prolonged periods of time, there is a risk of acute mediastinal shift into the empty hemithorax and profound cardiovascular instability
  • Drain removed as soon as possible, often D1 post-operatively

Pulmonary complications Cardiovascular complications Other complications
Pneumonia Arrhythmias esp. AF (20%) Unplanned ICU admission
Bronchopleural fistula (≤20%) Inotrope use (4%) Repeat surgery (5%)
Pulmonary oedema (2-5%) Myocardial infarction
Aspiration Major haemorrhage
Acute lung injury (4-10%) ± ARDS Cardiac herniation (rare)