Barbagallo M, Ortu A, Spadini E, Salvadori A, Ampollini L, Internullo E, Ziegler S, Fanelli G. Respir Care. 2012 Sep;57(9):1418-24
Randomised trial of 50 patients allocated to receive either continuous oxygen therapy or two cycles of helmet CPAP for 120 minutes. Results suggest that by the end of the second helmet treatment, patient's had a significantly higher PaO2/FiO2 but the improvement in oxygenation was not lasting. However, helmet CPAP was 'secure and well tolerated'.
Link to abstract.