760

(acid). Raising the temperature of crystal violetsolution from 20° to 37° C. caused only a small increasein adsorption (from 35 to 45%) ; the effect of tempera-ture change on the other substances would presumablybe of this order.

Practical useof this knowledge may be made by thesurgeon if he ascertains the weight of the standard packof gauze supplied him. If this weight, of gauze (xgrammes) is agitated with 10 x ml. of 0-1% solution ofproflavine sulphate BP for 5 minutes, then the solutiondripping from it contains 1 part in 1700 of the dye.From further experiments we have found that gauzeimmersed in the same proportion of 0,2% solution will

< drip a 1 in 1150 solution, while a 0-3% solution willsimilarly be transformed to a 1 in 400 (0-25%) solution.-

DESORPTION BY SERUM

Where the acridine-soaked dressings are in contactwith serum, as must often be the case in a wound, amuch higher degree of desorption occurs than withwater ; apparently the affinity of cotton fdr serum ismuch greater than its affinity for these antibacterials.This was shown as follows.The 1 g. samples of gauze used in the above experiments

were removed from the 0-1% solutions after 5 minutes andpressed out until the weight dropped to 1-5 g. The sampleswere then immersed in 10 ml. each of uncitrated horse serum(previously brought to pH 6- with carbon dioxide) and gentlyagitated for 5 minutes as before. The supernatant serumwas then compared in a colorimeter with dilutions of thevarious dyes in serum until a match was obtained with anidentical setting of both cups, a precaution necessary tocompensate for the straw colour of the serum. Because ofthis straw colour, it was difficult to get an accurate readingwith the yellow substances and all that can be said of themis that the serum appeared to strip practically all the colourout of the samples of gauze that had soaked in’ proflavineand 5-aminoacridine solutions. On the other hand, with thered 2 : 7-diaminoacridine and with crystal violet sharply definedresults were obtained, and it will be seen from the table thatonly 11-16% of the dye to which the gauze had had accessresisted extraction in the first 5 minutes of contact with serum.

It is possible that the experimental conditions wereslightly more favourable than those that might be metwith clinically, and the use of non-absorbent dressingswith acridines would still seem preferable where con-venient, but there is little doubt that the danger arisingfrom absorbent dressings has been exaggerated.

SUMMARY

The amount of proflavine, 2:7-diaminoacridine, 5-aminoacridine, acriflavine and crystal (" gentian")violet adsorbed by absorbent gauze under variousconditions has been determined.

This adsorption varies considerably among thevarious substances. Of the neutral-reacting acridines,5-aminoacridine is least absorbed.The speedy reversal of this adsorption by water and

particularly by serum indicates that dressings that havebecome impregnated with these chemotherapeuticsubstances.may be regarded as depots which are capableof supplying a significant proportion of these substancesto wounds with which they are in contact.

This state of affairs is shown to be in harmony withrecent bacteriological findings and at variance with acurrently held belief in the incompatibility of acridinesand absorbent dressings. However, the use of non-absorbent dressings is still recommended when it isdesired to expose the wound to the fullest concentrationof the medicament from the moment of application.

REFERENCES

Albert, A. and Gledhill, W. S. (1943) Lancet, ii, 238.Fleming, A. (1940) Proc. R. Soc. Med. 33, 487.Savage, R. M. (1943) Pharmaceut. J. 151, 53.

TETANUS ANTITOXIN.&mdash;The Ministry of Health recom-mends 3000 international units of tetanus antitoxin as theminimum prophylactic dose. Burroughs Wellcome and Co.are therefore discontinuing the 1000 unit packing of ’Well-come ’ brand refined tetanus antitoxin-globulins. As afurther safeguard against inadequate prophylactic dosage,multiple-dose packings containing 1000 units per c.cm. arealso to be discontinued.

Reviews of Books

Surgery of Repair -

D. N. MATTHEWS, MD, M CH CAMB., squadron-leader,surgical officer ill charge, RAF plastic unit. (BlackwellScientific Publications. Pp. 386. 45s.)

THIS readable and useful book, while it deals withplastic surgery and injuries to the bones of the face, willbe of great use to the general surgeon. The -principlesupon which the surgery of repair is based are satisfactorilyand simply laid down. This subject can no longer beregarded as obscure, and a suitable one only for a parti-cularly gifted few ; it emerges into the realm of ordinaryworked-out and accepted surgery in which anyone, aftera sufficient apprenticeship, can become an efficientpractitioner. Squadron-Leader Matthews is at his bestin describing plastic operations on the face. His recom-mendation of the use of chromic gut for tendon suturewill not receive wide acceptance by general surgeons, andthe cursory way in which the results of suture of theflexor tendons of the fingers in their sheaths are appraiseddoes not denote a significant experience of such work.His preference for the open method of obtaininggrafts of the fascia lata is noteworthy. The book isprofusely illustrated, the line drawings being parti-cularly good.

Modern Operative Surgery(3rd ed.) Editor : G. GREY TURNER, MS DURH., FRCS.(Cassell. Vol. II. Pp. 2236. 55s.)

THE outstanding feature of this second volume, as ofthe first, is the practical nature of the instruction. Thestandard of writing is high and even, and the methodsrecommended are reliable. Ogier Ward, in his articleon disease of the bladder, states the general opinionthat for ectopia vesicse the ureters should be trans-planted and no attempt made to reconstruct the bladderand urethra-sound advice, though the work of H. H.Young might have been mentioned. The haemostatic bagrecommended for prostatic haemorrhage is usually sopainful that the time has probably come to discard it.Ward is an expert in perurethral methods of prostatec-tomy, but his views conform with those usually held inthis country. Almost any section of the book can bepraised, but those written by Geoffrey Jefferson areparticularly good. The editor, in a first-class accountof cancer of the rectum, describes conservative methodsof resection. These two volumes seem to embody allthat is good in English surgery.

Barometric Pressure ,

PAUL BERT’S Researches in Experimental Physiology,translated by M. A. HITCHCOCK and F. A. HITCHCOCK.(Columbus, Ohio : College Book Co. Pp. 1055.$12.)

AERONAUTICAL medicine was in its infancy only fiveyears ago and today is a flourishing adult; with severaljournals and at least one large textbook of its own.Piety has come upon its followers. They are beginningto look back with respect upon their fathers which begatthem, the early pioneers of respiratory physiology’, .

Boyle, Lower, Mayow and-Hooke of the early Oxfordschool, Black of Edinburgh, Joseph Priestley, Lavoisier,and a host of others who laid the foundations for the workof the newer Oxford school of Haldane, Douglas anda later Priestley, for Barcroft of Cambridge and Hender-son of Yale. Of the respiratory physiologists of themiddle period the most famous is Paul Bert, whose greatwork La Pression Barom&eacute;trique was published in 1878.The book has for long been almost unobtainable and thepresent translation is welcome. It makes fascinatingreading, for Bert could write as well as think, and thetranslation has been carefully done. Some of the chapterheadings alone (" the lofty regions of the globe," " moun-tain journeys," " the volcanos of the Pacific ") are aninvitation to browsing. His discourse ranges fromballoon ascents to diving bells and he somehow relatesto these, and to each other, wine ferments, the geo-graphical distribution of plants, the putrefaction of eggs,the ripening of fruit, the nature of viruses, the travels ofMarco Polo, and the curious behaviour of MistressHervey. .