Epidemiology
- Thoracoplasty is currently indicated only to close a persistent pleural space (used in the past to treat TB)
- Risk factors for increased mortality post-thoracoplasty: preoperative cavitary disease/ previous artificial pneumothoraces on the opposite side/ older age at operation/ male sex
- Associated with: COPD
Physiology
- Pulmonary HTN due to chest wall disease (secondary removal or surgical reversal of ribs, resulting in decreased thoracic volume)
- Hypoventilation leads to hypoxia/ acidosis (with resultant pulmonary vasoconstriction)
Diagnosis
- ABG: hypoxemia/hypercapnia
PFT: restrictive pattern (may worsen over time due to progressive scoliosis/ defect is not correlated with extent of thoracoplasty)
-FEV1: decreased (typical 60% reduction)
-VC: decreased (about 50% predicted)
-TLC: decreased (about 65% predicted)
-RV: relatively preserved (about 90% predicted)
-FRC: mildly decreased (about 70% predicted)
-DLCO: decreased (with normal DLCO/VA)
-MVV: decreased (about 40% predicted)
-Lung compliance: decreased (due to lung compression by distorted chest wall/ fibrosis of lung due to underlying TB)
Exercise test: decreased exercise capacity (decreased VO2max) due to ventilatory limitation
Clinical
- Dyspnea
- Chronic Hypoventilation (see [[Chronic Hypoventilation]])
-Post-surgical chest wall changes
Complications: cor pulmonale/ hypercapnic respir-atory failure
Treatment
- Treatment of underlying OSA/ obstructive airway disease
- Nocturnal assisted ventilation: improves both day/ night ventilation
References
- xxx