1.   Directly measured tissue oxygen tension and arterial oxygen tension assess tissue perfusion.

2.   The arterial oxygen saturation and pulse rate of all patients were monitored by pulse oximetry before and during the procedure.

3.   Comparison of mean arterial oxygen saturation between the groups showed significantly higher levels in the nasal oxygen group throughout the procedure.

4.   Addition of almitrine enhanced the effect of inhaled NO on arterial oxygen partial pressure with only a small effect on haemodynamics.