2001e-160 accidents adverseeffects anecdotes anesthesia anesthesiology anesthetics casestudies complications inhalation inhalationanesthesia instrumentation intraoperativemonitoring methods monitoring physiologic point-of-caretesting surgicaltechnology wo200l674n1988 wo200u89n1983 wo240 wo240d717u1974 wo240w257a1985 wo277b347p2001a