Mechanical ventilation (NCMV) using extra-tracheal continuous gas insufflation (ETCGI) and nitric oxide (NO) has been used for patients with ALI(1).The purpose of this preliminary study was to compare the conventional mechanical ventilation (CMV) through lung protective ventilation versus the effect of ETCGI using NO mixture, on oxygenation and ventilation parameters in patients with ARDS and refractory hypoxemia.
Five patients (four women) with severe systemic inflammatory response syndrome, multiple organ system failure (ApacheII:26,88,5±2,99) and ARDS (LIS:3,75±0,3) with refractory hipoxemia (PaO2/FiO2:52,06±2,14 torr and SatO2:65,2±4,20 cmH2O) were studies. The sequential ventilatory support protocol was: 1.Protocol CMV: Initial PRVC:Pressure regulated volume control or PCV: Pressure controlled ventilation to 6,28±0,38 ml/kg tidal volume (protective ventilation), optimizing best Peep (17,4±1,81 cmH2O) and NO. 2.Protocol NCMV: Subsequently changes ventilation mode to PRVC or PCV, with Peep (2,4±0,54 cmH2O), ETCGI (9,0±2,64 liters/minute) and Nitric Oxide (3,92±0,83 ppm). The tidal volume, finaly was: 11,97±1,89 ml/kg and the volume minute was 15654±3050 ml/minute (range:12400-19600). The peak pressure (PIP) values in ETCGI mode, were obtained through tracheal level monitoring. All patients, the informed consent was obtained, less in two patients that was obtained differed.
See table: t-Student for comparative samples (95% CI).
1.- NO+ETCGI optimal application appears to improve oxygenation and ventilation substantially. 2.- All patients survived the refractory hypoxemia. 3.-One patient died due to refractory septic shock, after a new episode of sepsis. 4.- No high levels of NO2 (<1,0 ppm). 5.- No barotrauma episodes, in spite use high tidal volume (two patients development barotrauma previous and were treated with NO+ETCGI without ventilatory problems). REFERENCE: 1.Herrero S, Varon J, Fromm RE. “Nitric Oxide and Extratracheal continuous gas flow in the acute respiratory distress syndrome. Crit Care Med. December 2004. Vol. 32, No. 12 (Suppl.) P400.
1.- In life-threatening ARDS with refractory hypoxemia, it is possible to maintain an adequate PaO2 with the application of NO and ETCGi (considered as ”rescue treatment“) 2.- ETCGi can be performed even in presence of previous barotrauma.
Santiago Herrero, None.