Adaptive Servo Ventilation in Acute Cardiogenic Pulmonary Edema

Background: Noninvasive intermittent positive-pressure ventilation (NIPPV) is known to be benefit in the immediate treatment of patients with acute cardiogenic pulmonary edema. However, certain amount of patients cannot tolerate NIPPV because of discomfort. To date, adaptive servo ventilation (ASV), the new type of NIPPV, has not been evaluated in patients with acute cardiogenic pulmonary edema. We assessed the efficacy and feasibility of ASV. Method and result: Twenty-three patients (age,82±9years; NYHA, 4±2; BNP, 930±161) were applied ASV with its basic mode (expiratory pressure, 5cmH2O; pressure support, 3 to 10cmH2O). Nineteen patients (82.6%) were tolerable. ASV was associated with significant improvements at 1 hour after the beginning of treatment in blood pressure (156±31/85±18 to 116±17/65±14 mmHg, p<0.01), heart rate (110±18 to 88±21/min, p<0.01), respiratory rate (26±4 to 20±4/min, p<0.01), and peripheral oxygen saturation (87±10 to 94±7, p<0.01). The mean duration of therapy was 17±2 hours. Four patients who could not tolerate ASV had all shallow breathing and lack of cooperation because of agitation. Conclusion: In patients with acute cardiogenic pulmonary edema, ASV induces a rapid improvement in respiratory distress and hemodynamics. Even in elderly patients, ASV therapy is effective and feasible as long as their spontaneous respiration is preserved.