Fill in the Blanks 169-testOnline version 169-test by Farhad Key 1 because cough it remained opium anesthetics inhaler crude transported Before effective , surgery was very and very painful . Before 1800 , alcohol and had little success in easing pain during operations . Laughing gas was used in 1844 in dentistry in the USA , but failed to ease all pain and patients conscious . Ether ( used from 1846 ) made patients totally unconscious and lasted a long time . However , could make patients during operations and sick afterwards . It was highly flammable and was in heavy glass bottles . Chloroform ( used from 1847 ) was very effective with few side effects . However , it was difficult to get the dose right and could kill some people of the effect on their heart . An helped to regulate the dosage .