Which indicator is most critical for determining suitability for a pneumonectomy?

The most critical indicator for determining suitability for a pneumonectomy is FEV1 levels. FEV1, or Forced Expiratory Volume in one second, reflects the amount of air a person can forcibly exhale in one second and is a key measure of pulmonary function.

In the context of a pneumonectomy, which involves the surgical removal of a lung, sufficient pulmonary reserve is essential. Evaluating FEV1 provides insight into how well a patient can perform respiratory functions after losing a lung. A lower FEV1 may suggest that the lungs could be compromised further by surgery, increasing the risk of postoperative complications.

By assessing FEV1, healthcare providers can gauge the patient's ability to cope with the reduction in lung capacity post-surgery and estimate the functional impact on the remaining lung. This helps ensure that only those patients with adequate functional reserve are considered for such a significant procedure, thus supporting better surgical outcomes and limiting the risk of respiratory failure.

While other indicators like PaO2, maximum VO2, and PaCO2 can be informative regarding overall lung function and oxygenation, they do not provide the same direct insight into the lung's capacity for ventilation and the risk associated with lung resection as FEV1 levels do.