No reduction in the sufentanil requirement of elderly patients undergoing ventilatory support in the medical intensive care unit. - Hofbauer,R.; Tesinsky,P.; Hammerschmidt,V.; Kofler,J.; Staudinger,T.; Kordova,H.; Vrastiolovat,M.; Frass,M.; Freye,E. (Eur J Anaesthesiol, 1999)