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573 food poisoning.-Dr. F. PARKES WEBER did not agree there was an absence of literature dealing with the clinical symptoms of coronary obstruction ; it was to be found under two headings : angina pectoris and status anginosus. The older contributions supplied the main basis for the coronary theory of the causation of angina pectoris.-Sir WILLIAM WILLCOX spoke of two cases of the condition he had seen, in one of which a toxin-that of trench fever-seemed to have played a part. The PRESIDENT described a case in which abdominal pain was prominent. Even in very large doses morphia had no effect on it. ROYAL SOCIETY OF MEDICINE. SECTION OF ANÆSTHETICS. AT a meeting of this Section on March 7th a paper on SPINAL ANALGESIA WITH SPINOCAIN was read by Mr. CHARLES DONALD. He recalled that spinocain was devised by Pitkin, of New Jersey, to overcome some of the difficulties encountered with the analgesics usually injected into the spinal canal. Pitkin, he said, claims for its absolute controllability over height, absolute maintenance of blood pressure, an almost absolute freedom from complications, and satisfactory analgesia in operations below the diaphragm. To this end he employs novocain as the least toxic analgesic, mixed with alcohol to make it a " light " solution, a viscous derivative of starch to limit absorption and diffusibility, and strychnine to act on the vaso-constrictors in the anterior roots. A separate administration of novocain and ephedrine is previously made into the track of the spinal needle, their respective effect being to prevent pain on passing the larger needle and to raise the blood pressure. The solution, said Mr. Donald, has been given in 150 cases at the London Hospital and a smaller series, using crystalline neocaine and novocain, has also been done. As regards control over the height of analgesia, the technique of dosage, expansion of the indiffusible medium before injection, and the assumption of the Trendelenburg position, Pitkin’s recommendations have been followed and various modifications have been tried to test the claims. The statement that absorption is relatively slow appears to be correct, for the equivalent amount of pure novocain gave, as a rule, greater analgesia. The use of the Trendelenburg position seemed only to cause a slight delay in the analgesia reaching the average height it attained if injected into a patient in the horizontal position. The same can be said of the indiffusibility. Waywardness in extent occurred as with other analgesics, and those in whom there was much over-action comprised the old, the very ill, and the flabby. Dosage and the type of patient were the only two recognisable factors. Out of 54 cases in which careful readings of blood pressure were taken, 17 had a fall of more than 20 mm. Hg. In seven the fall was 50 mm. or more. The fall was in no way proportional to the height of analgesia and therefore not to the number of anterior roots involved. In 18 of the cases analgesia reached to the second rib or higher ; in only six was there a fall of more than 20 mm. ; in several of these the pressure actually rose. Strychnine has never proved itself in these cases. Ephedrine does not prevent a fall, but as recovery is taking place there is apparently a quicker restitution to normal. The cases which showed falls in pressure were prostatectomies, gravely ill patients, cases of severe peritonitis, and a very few cases of simple operations. In the last the fall might be attributable to psychological causes. There were certainly very few complications, said Mr. Donald. One moribund patient died on the table, but it is to the credit of spinocain that others in like state did not. Old, shocked, or toxic they took it well. There have been no palsies and only four severe headaches. Post-operative vomiting has been rare, much rarer than with novocain or- neocaine, but the claim of rapid emptying of the bowels and non-occurrence of ileus has not been substantiated. The dose of spinocain can be pushed to cover higher abdominal operations, but then occasionally pain is complained of, and there is retch- ing during the intra-abdominal manipulations. Failures have been met with after a long series of successes, and it is possible that the novocain may have deteriorated in solution. Spinocain has not justified its major claims as to the controllability and maintenance of blood pressure, but the results, confirm Koster and Kasman’s experimental and clinical observation that respiratory and blood pressure dangers have been overestimated-at least when neocaine and novocain are used and the Trendelenburg position is employed during the operation. Dr. W. HOWARD JONES read a paper on Percain : A New Regional and Spinal Anœsthetic. Spinal analgesia, he said, results either from simple intradural caudal block or in the dorsal region thoracic nerve root block. The nerve trunks of the cauda equina are directly accessible to a needle through any of the lumbar interspaces ; the thoracic roots are- remote from the needle point and in the past have- been reached by the following methods (1) Gravita- tional diffusion resulting from the injection of a. solution relatively heavier, than the spinal fluid- (2) Barbotage or mixing the dose in the syringe with, spinal fluid and repeated withdrawal and reinjection, of fluid, usually completed by gravitational diffusion- (3) Replacement of a large quantity of spinal fluid withdrawn into a syringe containing the dose of drug, also likely to be completed by gravitational diffusion. A New Method.-The method now advocated is that of treating the subarachnoid space in the same- manner as the tissues and injecting it under pressure- without withdrawing any cerebro-spinal fluid to the.- limit required by the operation. The volume dosage has been arrived at in the adult by injecting a series of consecutive cases with increasing quantities of solution and recording the levels reached. Egtreme- accuracy is not essential; splanchnic block requires that the solution shall pass the roots of D 5, but it must not reach the cervical roots, especially the main phrenic roots of C 4. A satisfactory level to reach i& D 2 or D 3. The adult spine varies in length; a varia- tion of about four inches has been found in the measurement between the inter-iliac line and the- seventh cervical spine, in full flexion. The volume- dosage for splanchnic block has been between 16 and 20 c.cm. of solution proportional to a relatively short or long spinal tube. Lower levels are reached by correspondingly smaller volumes of solution. A New Drug.-For the first time in the history of spinal analgesia a drug is available which is potent, in such high dilution that the amount dissolved add& next to nothing to the specific gravity of the vehicle- For thoracic nerve root blocks percain solutions of 1-2000, 1-1500, and 1-1000 are used according to the duration of analgesia required. The solvent has, been normal saline 0-9 per cent. and 0-5 per cent.. saline. The specific gravity of normal saline solutions is 1-006 in allthree strengths. That of the 0-5 per cent. saline solutions is 1-003. Cerebro-spinal Fluid.-The specific gravity of the cerebro-spinal fluid varies between 1-003 and 1.010, the more usual being probably 1005-1-008- This variability is the most important thing to recognise and remember when using the method under considera- tion. Comparing percain solutions with these fig-errel:;c it will be seen that normal saline solutions may be hyper-, iso-, or hypobaric and that they will be- frequently hypobaric. The 0.5 per cent. saline solu-- tions (spec. grav. 1-003) will almost certainly be hype- baric. If a normal saline solution should turn ou?. to be hyperbaric the danger to the patient in the .:
