[Inhalation administration of nitric oxide during selective pulmonary ventilation decreases the intrapulmonary shunt].

OBJECTIVE

To assess the effects of inhaled nitric oxide (NO) on oxygenation and hemodynamics in patients undergoing lung resection surgery during one-lung ventilation (OPV).

PATIENTS AND METHODS

Prospective study of 16 patients aged 62 +/- 10 years scheduled for chest surgery under combined general and epidural anesthesia. During ventilation of only one lung, NO was administered for 15 minutes. Arterial blood and mixed venous blood samples were taken for analysis of blood gases and the calculation of intrapulmonary shunt. Pulmonary and systemic hemodynamic variables were also recorded using a Swan-Ganz catheter at three times: baseline (ventilation of both lungs), OLV, and with OLV plus NO (OLV NO).

RESULTS

The most relevant data consisted of a significant decrease in shunt after start of NO inhalation in comparison with the level during OLV (31.1 +/- 0.5% versus 36 +/- 0.6%; p < 0.05). Arterial oxygen pressure decreased significantly during OLV and increased after start of NO (118.9 +/- 53.6 versus 155.4 +/- 78.5 mmHg; p < 0.05). Mean pulmonary artery pressure, pulmonary and systemic vascular resistances, and cardiac index did not change with inhalation of NO.

CONCLUSIONS

Inhalational administration of NO during OLV significantly improves arterial oxygenation and decreases intrapulmonary shunt during OLV, without causing hemodynamic or systemic effects.