9. ROLE OF SURGERY

The treatment of MDR- and XDR-TB is primarily chemotherapy. There are, however, limited indications for surgery and these presume that the disease is mainly localised, unilateral and that there is adequate cardiopulmonary reserve. For patients with localised disease, surgery can significantly improve treatment outcomes, provided skilled thoracic surgery and excellent post- operative care are available. A multidisciplinary team approach should be employed when dealing with patients being considered for surgery.

Major indications

• Persistence of positive sputum cultures and lack of radiographic and clinical improvement after six months of adequate therapy and patient adherence.
• Relapse in the same site after a previous adequate course of chemotherapy in a patient who has been adherent.

Minor indications

• In a patient who has undergone sputum conversion but the profile of drug resistance is so great (e.g., resistance to more than four drugs) that if relapse did occur it may be difficult to re- establish sputum culture conversion.
• In a patient who has undergone sputum conversion but there is residual cavitation or gross lobe or lung destruction and hence the potential for relapse.

At least six months of treatment should be given before surgery is considered. In a patient who has not undergone sputum conversion, surgery should only be performed when there is no further possibility of an adequate chemotherapeutic regimen. The decision to perform surgery and the extent of surgery (lobectomy or pneumonectomy) should preferably be made after anatomical localisation of disease by CT scan. Often the apex of a lower lobe is involved together with a corresponding upper lobe and the former should also be removed. Minimal contra lateral disease is not a contra-indication to surgery. The role of PET-CT scans in guiding surgery remains unclear. Perfusion scans are useful in establishing how much functioning lung is likely to be removed. Basic spirometry (FEV1 and FVC) is adequate in assessing lung function in the majority of patients. Eligible patients should have a FEV1 > 0.8. If the FEV1 is acceptable, analysis of blood for HCT, ABG, urea and electrolytes, creatinine should be performed pre-operatively.  ECG is useful for excluding pulmonary hypertension which would contraindicate surgery. A pre-operative ECG should be routinely performed on patients older than 50 years and on patients with diabetes.

The resected part of the lung should be sent for histology, culture and drug susceptibility testing. Sputum cultures should be performed immediately post-surgery and then monthly until two consecutive negative cultures have been obtained. If the patient was culture-negative at the time of surgery the treatment should continue for at least 18 months after culture conversion. If the patient was culture positive, treatment should continue for another 24 months.