NEUROLEPTANALGESIA is based upon the use of a tranquilizer and a narcotic administered intravenously to produce a state of psychic withdrawal and profound analgesia.1 Several series of tranquilizers and narcotics have been investigated in Europe; those currently available for investigation in the United States, droperidol2 and fentanyl citrate,3 represent the most evolved of these so far.
Droperidol, a butyrophenone, is a potent tranquilizer which produces in the patient a state of calm, disinclination to move, and "disconnection" from the surroundings. It has an α-adrenergic blocking effect, which offers some protection against shock, leads to good peripheral perfusion, and "unmasks" hypovolemia. It also protects against epinephrine-induced arrhythmias, and has an antiemetic effect.
Droperidol may cause hypotension by virtue of its α-adrenergic blocking effect and peripheral vasodilatation, particularly when the drug is administered rapidly and in the presence of hypovolemia. The hypotension is usually transitory in the former case,
FOX JWC, FOX EJ, CRANDELL DL. Neuroleptanalgesia for Heart and Major Surgery. Arch Surg. 1967;94(1):102-106. doi:10.1001/archsurg.1967.01330070104021