Role of nitric oxide in treatment of acute lung injury after surgery with extracorporeal circulation

Postoperative acute lung injury (ALI) compromises oxygen transfer across alveolar-capillary membrane with consecutive hypoxia, one of its indicators being reduction of oxygenation index PaO2/FiO2 below 40 kPa (300 mm Hg). Management of ALI includes different procedures like mechanical lung ventilation (MLV), drugs and others. One of the new possibilities for treatment of ALI is nitric oxide (NO) inhalation. The aim of this prospective study was to examine the role of NO inhalation in treatment of ALI. 14 patients with ALI developed immediately after operation with extracorporeal circulation (ECC) were included in the study. Group A (n = 8) inhaled NO and group B (n = 6) did not inhale NO during treatment of ALI. All other therapeutic measures were the same in both groups. The groups were similar in relation to demographic data, type of surgery and duration of ECC. PaO2/FiO2 was calculated before operation (T1), immediately after surgery (T2) and after lung recovery, when the need for MLV stopped (T3). The duration of MLV was also registered. PaO2/FiO2 (kPa) in referent times was in group A 54.9 +/- 1.6, 33.8 +/- 1.2 and 46.2 +/- 0.8 and in group B 52.2 +/- 1.1, 33.5 +/- 1.5 and 47.3 +/- 0.9, respectively. There was a statistically significant decrease of PaO2/FiO2 in T2 and T3 vs T1 in both groups (p < 0.05), while the difference between the groups was not statistically significant. The duration of MLV (h) in group B (28.5 +/- 1.6) was statistically significantly shorter than in group A (63.1 +/- 8.7) (p < 0.01). According to the results of this study we conclude that NO inhalation during ALI after surgery with ECC significantly reduces the duration of MVL and improves pulmonary recovery.