EXTRADURAL BLOCK WITH XYLOCAINE A Preliminary Report.

XYLOCAINE was the name given by Lofgren and Lundquist in 1943 to a basic anilide of the chemical structure-w-diethylamino-2.6.dimethylacetanilide. This drug, chosen from a number of similar compounds, was investigated clinically by Gordhl, who gave a very favourable report on its properties. Xylocaine is very stable in solution, is not destroyed by repeated boiling and with the addition of adrenaline, has a pH of 4.0. The maximum safe dose is stated to be between 0.5 and 1 gramme, but experimentally, as much as 3 grammes has been given with recovery. The drug is supplied in 20 c.cm. vials in 2% and 1 % strength with or without adrenaline. The duration of analgesia of the 2 % solution is said to be 98 minutes, and with the addition of 1 in 100,OOO adrenaline, 323 minutes. The duration of analgesia with the 1 % solution is considerably less. These figures were not confirmed by the present investigators, the maximum figure for the 2% solution being 195 minutes, and for the 1%, 120 minutes. A special 1% solution has been put up by the courtesy of the manufacturers, with a specific gravity of 1.003. This is used in thoracic work, in case of an accidental spinal block, where the adoption of a head down position would cause the solution to diffuse away from the medulla. The onset of analgesia is more rapid with xylocaine than with any other local analgesic, a feeling of warmth being perceived within 5 minutes, and complete analgesia occurring within 10 minutes. This is a great advantage in extradural block, as with other drugs it is necessary to wait 20 to 30 minutes before the patient is ready. The present investigation is based on a series of 108 extradural blocks, given for a variety of surgical operations, etc., as shown in the following tableGastrectomy . . . . . . . . . . . . . . . 9 Oesophagectomy . . . . . . . . . . . . I Incarcerated diaphragmatic hernia . . . . . . I Cholecystectomy . . . . . . . . . . . . 6 Hemicolectomy, Laparotomy . . . . . . 10 Acute Intestinal Obstruction . . . . . . . . . 2 Nephrectomy . . . . . . . . . . . . . . . 4 Rostatectomy . . . . . . . . . . . . . . . 3 Appendicectomy . . . . . . . . . . . . 10 &sarian Section . . . . . . . . . . . . 3 Abdominal Gywology . . . . . . . . . 37 Perineal G y m l o g y . . . . . . . . . . . . 3 Inguinal Herniotomy . . . . . . . . . . . . 9 Minor Operations . . . . . . . . . . . . 4 Therapeutic Cases . . . . . . . . . . . . 6