Should patients have cardiac catheterization prior to long-term oxygen treatment?

Pulmonary arterial pressure predicts survival in patients with hypoxic chronic obstructive pulmonary disease as does the presence of cor pulmonale. Thus, cardiac catheterization has been performed prior to treatment for long-term oxygen therapy (LTOT) in order to 1) assess the suitability of patients for LTOT, 2) predict survival in patients receiving LTOT and 3) for research in cor pulmonale. In this review I will submit the evidence which suggests that these indications for measurement of pulmonary haemodynamics are not justified, and measurements of arterial blood gas values and assessment of airflow limitation are all that is necessary prior to LTOT.