2
624 during which only 3 (1-01%) reactions were observed. These observations are summarised in table 111. Results and Observations In 296 transfusions of whole blood, packed cells, or serum given through silicone-rubber tubing to patients attending the department of hæmatology, Manchester Royal Infirmary, during a period of seventeen months only 3 reactions (1-01%) occurred. This incidence of reactions is of the same order as has been observed with natural rubber tubing under similar conditions at the same hospital clinic (Stratton 1955). The following advantages of silicone rubber were noted : (1) The most satisfactory specimens of silicone rubber withstood a large number of sterilisations by autoclaving without serious deterioration in properties. Four different compositions of silicone rubber were in satisfactory condition for further use after over 40 transfusions, and one reached 59. In contrast, various natural rubber tubings under similar conditions showed much deterioration after 6-12 sterilisations. (2) The general water-repellent properties of silicone polymers is well known (McGregor 1954). In the case of silicone-rubber tubing this leads to reduced wetting by fluids, including blood, and a reduction in the tendency to coagulate on the surface during a prolonged transfusion. (3) The most satisfactory silicone rubbers ’used in this work, colour codes yellow, orange, and green, are transparent. This facilitates the important initial step of displacement of air from the tubes bv saline solution. (4) Silicone-rubber tubing is superior to natural rubber for procedures involved in separation, storage, and therapeutic use of blood-platelets, which adhere to natural rubber. (5) Owing to its excellent ageing characteristics, silicone rubber can be stored for long periods without deterioration. We conclude that, on the basis of their resistance to repeated autoclavings, their use for blood-transfusions, their transparency, and the ease of their fabrication, the silicone rubbers, consisting of a dimethylpolysiloxane gum, filled with either an amorphous precipitated silica or a pyrogenic silica (colour code orange and yellow respectively) are the most suitable of the tested rubbers for use in blood-transfusion. Summary The results of 296 transfusions of whole blood, packed cells, and serum through seven types of silicone-rubber tubing are reported. In the course of these transfusions only 3 reactions (1-01%) in patients were observed. Because of its resistance to repeated sterilisation, its relatively long life in good condition, its transparency, and its physiological inertness, silicone rubber is superior in every way to natural rubber for blood-transfusion work and is recommended for this purpose. The most satisfactory compositions of silicone rubber so far examined are a dimethylpolysiloxane gum filled with either an amorphous precipitated silica or a pyro- genic silica. Our thanks are due to the medical, nursing, and technical staffs of the department of hsematology, Manchester Royal Infirmary, for their help throughout these clinical trials. REFERENCES Barondes, R. de R., Judge, W. D., Towne, C. G., Baxter, M. L. (1950) Milit. Surg. 106, 379. Bolton Carter, J. F. (1951) Lancet, ii, 20. Brudenell, J. M. (1954) Ibid, i, 517. Busman, G. J. (1920) J. Lab. clin. Med. 5, 693. Fletcher, R. F. (1956) Lancet, i, 509. Gale, J. W., Curreri, A. R., Young, W. P., Dickie, H. A. (1952) J. thorac. Surg. 24, 587. Handfield-Jones, R. P. C., Lewis, H. B. M. (1952) Lancet, i, 585. Harrow, B. (1941) Textbook of Biochemistry. London. Jacques, L. B., Fidlar, E., Felstead, E. T., MacDonald, A. G. (1946) Canad. med. Ass. J. 55, 26. MacDougall, J. D. B. (1953) Nature, Lond. 172, 124. McGregor, R. R. (1954) Silicones and Their Uses. London. Rowe, V. K., Spencer, H. C., Bass, S. L. (1948) J. industr. Hyg. 30, 332. Stokes, J. D., Busman, G. J. (1920) J. Amer. med. Ass. 74, 1013. Stratton, F. (1955) In Modern Trends in Blood Diseases (edited by J. F. Wilkinson). London ; p. 316. Symposia BONE IT is now an established custom in St. Andrew University that each year a prælector is appointe is attached for a few weeks, usually in late August September, to one or more of the departments the medical faculty. This year Prof. P. Lacroix, of Institute of Anatomy at Louvain University, holds prselectorship, and during his visit he has been mainly with the department of physiology, Quee College, Dundee, the orthop2edic department at Royal Infirmary, and the anatomy department Salvator’s College, St. Andrews. On Sept. 5 a symposium on bone was held in College, Dundee. The principal feature was a lecturt Professor Lacroix ; but several members of St. Andr University staff and Prof. G. M. Wyburn of also contributed. Prof. G. H. BELL referred to recent work by him and Mrs. Oliver on experimental lathyrism in rat; this condition the bone quality is reduced even w the inorganic component is not altered in quantit quality. Mr. J. A. GILLESPIE, in a communication on influence of the nervous system on bone growth, st that his experiments had led him to the conclusion motor nerves have no direct influence on bone grow but that they exert their effect indirectly through action of muscles. Dr. J. W. SMITH and Prof. R. WALMSLEY gave pa on experimental fatigue in bone, and correlated variation in Young’s modulus in different parts of same bone with compression and tension forces and with the orientation of the collagenous fibres in osteons. Professor WYBURN spoke on ectopic bone and s that, although bone cells are not essential for the i tion of osteogenesis in transplants, there is a immediate response to fresh autogenous grafts, v suggests a more abundant or more active inducti in fresh than in stored or prepared grafts. Mr. J. HUTCHISON in a paper on dyschondroplas diaphyseal aclasis stated that he believed that m condition there was a failure of ossification in the parts of the epiphysis and also at its periphery. Mr. I. M. STEWART gave an account of the prepara of cancellous bone homografts and said that there no reported mention of this type of graft. He s radiographs and photographs of a graft site a explorative operation to prove the efficacy o material. Mr. 1. S. SMILLIE, in a communication on chondritis dissecans, reviewed the subject of loose in joints and expressed the view that they result trauma. He pointed out that the classical loose always contained bone, and that when this detached a fracture might occur in the bone immediately underlay the articular cartilage. Professor LACROIX, speaking on bone growt repair, began by reviewing the growth process in thf r of the epiphyseal cartilage of a quickly growing and referred especially to the complex structure may be observed at the periphery of the epip cartilage. When epiphyseal or " growth " cartil transplanted to various sites it produces bone similarly to the process in situ. After a few this transplanted cartilage has reconstituted at is

Symposia

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624

during which only 3 (1-01%) reactions were observed.These observations are summarised in table 111.

Results and Observations

In 296 transfusions of whole blood, packed cells, orserum given through silicone-rubber tubing to patientsattending the department of hæmatology, ManchesterRoyal Infirmary, during a period of seventeen monthsonly 3 reactions (1-01%) occurred. This incidence ofreactions is of the same order as has been observed withnatural rubber tubing under similar conditions at thesame hospital clinic (Stratton 1955).The following advantages of silicone rubber were

noted :

(1) The most satisfactory specimens of silicone rubberwithstood a large number of sterilisations by autoclavingwithout serious deterioration in properties. Four differentcompositions of silicone rubber were in satisfactory conditionfor further use after over 40 transfusions, and one reached59. In contrast, various natural rubber tubings under similarconditions showed much deterioration after 6-12 sterilisations.

(2) The general water-repellent properties of silicone

polymers is well known (McGregor 1954). In the case ofsilicone-rubber tubing this leads to reduced wetting byfluids, including blood, and a reduction in the tendency tocoagulate on the surface during a prolonged transfusion.

(3) The most satisfactory silicone rubbers ’used in thiswork, colour codes yellow, orange, and green, are transparent.This facilitates the important initial step of displacement ofair from the tubes bv saline solution.

(4) Silicone-rubber tubing is superior to natural rubber forprocedures involved in separation, storage, and therapeuticuse of blood-platelets, which adhere to natural rubber.

(5) Owing to its excellent ageing characteristics, siliconerubber can be stored for long periods without deterioration.

We conclude that, on the basis of their resistance torepeated autoclavings, their use for blood-transfusions,their transparency, and the ease of their fabrication,the silicone rubbers, consisting of a dimethylpolysiloxanegum, filled with either an amorphous precipitatedsilica or a pyrogenic silica (colour code orange and

yellow respectively) are the most suitable of the testedrubbers for use in blood-transfusion.

SummaryThe results of 296 transfusions of whole blood, packed

cells, and serum through seven types of silicone-rubbertubing are reported. In the course of these transfusionsonly 3 reactions (1-01%) in patients were observed.

Because of its resistance to repeated sterilisation, its

relatively long life in good condition, its transparency,and its physiological inertness, silicone rubber is superiorin every way to natural rubber for blood-transfusionwork and is recommended for this purpose.The most satisfactory compositions of silicone rubber

so far examined are a dimethylpolysiloxane gum filledwith either an amorphous precipitated silica or a pyro-genic silica.Our thanks are due to the medical, nursing, and technical

staffs of the department of hsematology, Manchester RoyalInfirmary, for their help throughout these clinical trials.

REFERENCES

Barondes, R. de R., Judge, W. D., Towne, C. G., Baxter, M. L.(1950) Milit. Surg. 106, 379.

Bolton Carter, J. F. (1951) Lancet, ii, 20.Brudenell, J. M. (1954) Ibid, i, 517.Busman, G. J. (1920) J. Lab. clin. Med. 5, 693.Fletcher, R. F. (1956) Lancet, i, 509.Gale, J. W., Curreri, A. R., Young, W. P., Dickie, H. A. (1952)

J. thorac. Surg. 24, 587.Handfield-Jones, R. P. C., Lewis, H. B. M. (1952) Lancet, i, 585.Harrow, B. (1941) Textbook of Biochemistry. London.Jacques, L. B., Fidlar, E., Felstead, E. T., MacDonald, A. G. (1946)

Canad. med. Ass. J. 55, 26.MacDougall, J. D. B. (1953) Nature, Lond. 172, 124.McGregor, R. R. (1954) Silicones and Their Uses. London.Rowe, V. K., Spencer, H. C., Bass, S. L. (1948) J. industr. Hyg.

30, 332.Stokes, J. D., Busman, G. J. (1920) J. Amer. med. Ass. 74, 1013.Stratton, F. (1955) In Modern Trends in Blood Diseases (edited by

J. F. Wilkinson). London ; p. 316.

Symposia

BONE

IT is now an established custom in St. Andrew

University that each year a prælector is appointeis attached for a few weeks, usually in late AugustSeptember, to one or more of the departmentsthe medical faculty. This year Prof. P. Lacroix, of Institute of Anatomy at Louvain University, holds prselectorship, and during his visit he has been mainly with the department of physiology, QueeCollege, Dundee, the orthop2edic department at Royal Infirmary, and the anatomy departmentSalvator’s College, St. Andrews.On Sept. 5 a symposium on bone was held in

College, Dundee. The principal feature was a lecturtProfessor Lacroix ; but several members of St. AndrUniversity staff and Prof. G. M. Wyburn of also contributed.

Prof. G. H. BELL referred to recent work by himand Mrs. Oliver on experimental lathyrism in rat;this condition the bone quality is reduced even wthe inorganic component is not altered in quantitquality.Mr. J. A. GILLESPIE, in a communication on

influence of the nervous system on bone growth, stthat his experiments had led him to the conclusion motor nerves have no direct influence on bone growbut that they exert their effect indirectly through action of muscles.

Dr. J. W. SMITH and Prof. R. WALMSLEY gave paon experimental fatigue in bone, and correlatedvariation in Young’s modulus in different parts ofsame bone with compression and tension forces and with the orientation of the collagenous fibres inosteons.

Professor WYBURN spoke on ectopic bone and sthat, although bone cells are not essential for the ition of osteogenesis in transplants, there is a

immediate response to fresh autogenous grafts, vsuggests a more abundant or more active inductiin fresh than in stored or prepared grafts.

Mr. J. HUTCHISON in a paper on dyschondroplasdiaphyseal aclasis stated that he believed that mcondition there was a failure of ossification in the

parts of the epiphysis and also at its periphery.Mr. I. M. STEWART gave an account of the prepara

of cancellous bone homografts and said that thereno reported mention of this type of graft. He s

radiographs and photographs of a graft site a

explorative operation to prove the efficacy omaterial.

Mr. 1. S. SMILLIE, in a communication on chondritis dissecans, reviewed the subject of loose in joints and expressed the view that they resulttrauma. He pointed out that the classical loosealways contained bone, and that when this detached a fracture might occur in the bone

immediately underlay the articular cartilage.Professor LACROIX, speaking on bone growt

repair, began by reviewing the growth process in thf rof the epiphyseal cartilage of a quickly growing and referred especially to the complex structuremay be observed at the periphery of the epipcartilage. When epiphyseal or " growth " cartiltransplanted to various sites it produces bone similarly to the process in situ. After a few this transplanted cartilage has reconstituted at is

Page 2: Symposia

625

phery the complex structure that is a feature of normalbone, and this is to be regarded as an induction phen-omenon. Until a decade ago it was considered that suchan induction phenomenon was linked with the presenceof an organiser that differed from the inducing tissue,but numerous experiments cast doubt on this view.

Professor Lacroix then described some recent experi-ments in which dead epiphyseal cartilage transplantedunder the capsule of the kidney constantly resulted in’hf formation of bone in that site whereas ordinaryhyaline cartilage, similarly transplanted, is non-osteo-zenic. This has led to the conclusion that induction

processes are concerned in bone growth but that theirexact nature is still obscure.Before considering the process of bone repair, Professor

Lacroix analysed his experimental results in graftingperiosteum and bone-marrow. He found that periosteumfrom newborn animals produced cartilage in addition tobone; and even adult periosteum, although inactivebefore being grafted, constantly produced bone after

transplantation. Bone-marrow has also been found to beosteogenic after transplantation, but the resulting bonetends to be absorbed. In long-term experiments theussicle developing after transplantation of the cartilagefrom callus was found to have a histological appearancealmost identical with that of diaphyseal bone. ProfessorLacroix went on to say : " We deem therefore that thecartilage callus does more than merely weld provisionallythe pieces of a broken bone ; it not only provides thewelding material but integrates this welding material intothe urganisation of the bone undergoing repair." Bonetissue is also constantly obtained when callus cartilagethat has been killed by soaking in alcohol is transplanted,and it therefore appears that induction processes play arole in bone repair as they do in bone growth.In conclusion Professor Lacroix correlated his experi-

mental findings with the clinical picture of post-traumaticosteoporosis. Normal internal remodelling is most exten-,ive in the region of the bone metaphysis, and it is inthis very site that post-traumatic osteoporosis begins tohe seen radiographically. Post-traumatic osteoporosiswas shown to be associated with an internal remodellingf the bone that is more active than normal.

1. See Lancet, Sept. 1, 1956, p. 459.

Medicine and the Law

A Murder Conviction QuashedIN the Court of Criminal Appeal on Aug. 21, the

conviction of an American airman for the murder ofWalter Beaumont, aged 27, who had died at Hull RoyalInfirmary on May 12, 1956, was quashed. Medical evi-dence ralled on behalf of the appellant in the Appealcourt suggested that the treatment given to Beaumont

aF Hull Royal Infirmary had been palpably wrong.lLeels Regional Hospital Board has now unanimously

approved a report vindicating the staff of the Infirmary.The report. signed by three medical assessors (Prof. J. H.Buggart, Prof. John Bruce, and Dr. F. M. Parsons),

an inquiry held on Sept. 5.’flm a::e::ors find that " Beaumont’s treatment at

H Ji Infirmary was exemplary"; and they pay tributethe care and devotion shown by Mr. M. A. Morkos,’L*- surgical registrar, who moved into residence in thepital and stayed there, scarcely leaving the patient’s- .’.. from the time his postoperative state took an

ly :erious course. The assessors, in the light ofscrutiny of the post-mortem material and of the

cord, make the following observations :1 There is histological evidence of severe damage to the

- - ;’,.-’. tubutes (lower nephron nephrosis), which could only

have originated soon after his injury, and was sufficient tohave resulted in death. -

"(2) The autopsy showed extensive pulmonary lesions. Thesewere septic in -type, and vascular and perivascular in situation,indicating that they had resulted from the transport of smallinfected clots. The lesions contained coccal organisms,-an.dthere is no evidence of the presence of fungi or yeasts such asare sometimes seen in patients treated’with antibiotics.

" (3) Early meningitis was demonstrable at autopsy, andwe regard this as further evidence of a blood-borneinfection.

" (4) Death was hastened by the development of a catas-trophic postoperative enteritis. We have carefully consideredthe relationship of this to the administration of terramycin.We are aware that this complication sometimes arises in

patients treated with terramycin and other broad-spectrumantibiotics, but in these cases the cause of enteritis can beestablished as due to antibiotic-resistant staphylococci ratherthan to any inherently poisonous property of the drugs. Inthe present case, culture of the stools failed to yield staphylo-cocci, and we must therefore regard the cause of the enteritisas an open question, since a similar and fulminating enteritissometimes occurs after operations, especially on the abdomen,without any antibiotic therapy. In one view, the latter typeof postoperative enteritis is the sequel to a period of lowblood-pressure, and the occurrence of hypotensive lesions inthe kidney lends support to such a possible explanation in-this case.

" (5) The use of terramycin initially in Beaumont’s case wasin our opinion not incorrect, and there is good evidence of itsvalue in the treatment of peritonitis. Its withdrawal at theonset of diarrhoea was correct. By this time, the patienthad developed a fulminating gastro-enteritis as well as chestlesions, and these did not respond to penicillin. It was possiblyunwise of the resident surgical officer to resort again to

terramycin ; but since there was reasonable doubt about thecause of the enteritis, and since the patient was gravely illand febrile despite the administration of penicillin, the renewalof terramycin therapy was not unreasonable and certainly notblameworthy. In any event, the small quantity of terramycinwhich was then administered had no influence of any kind onthe outcome of the case. We believe, in fact, that beforethe second course was started, the patient’s state was

irreversible.

" (6) It seems to us that the management of the fluid-electro-lyte state should be considered in relation to three periods ofthe man’s illness :

(a) In the preoperative and operative period, the manage-ment of the fluid-electrolyte situation in our opinion wasadequate.

(b) In the early postoperative phase, the control of thefluid therapy was appropriate.

(c) In the late postoperative period, following the develop-ment of severe enteritis complicated by serious renal impair-ment and by lung infection, a highly complicated biochemicaldisturbance developed. The fluid loss from the bowel wasenormous and resulted in profound dehydration, one

evidence of which, apart from the careful clinical observa-tions of Mr. Morkos, was the concentration of haemoglobinin the blood (114%). As soon as possible, Mr. Morkosenlisted the aid of the hospital biochemist who thereafterperformed daily estimations on which the day-to-dayadministration of fluids was based. The amount of fluidadministered may appear large to those unfamiliar with themanagement of severe gastro-enteritis or cholera whichthis man’s diarrhoea resembled. It was perhaps fortunatethat Mr. Morkos had had some experience of the treatmentof cholera, and had the courage to apply this experience inthe management of this extremely difficult case. That theamount of fluid given was in no way excessive is borne outby the absence at autopsy of the usual findings of over-hydration, as, for example, oedema of the lungs, fluid in theserous cavities, or generalised dropsy."" It is our impression," the assessors add, " that

Beaumont was on the point of death on the fifth post-operative day " ; ; and his survival for a further three

days was due, in their opinion, to energetic and competentmeasures. ’’ In the event, and in the light of all theevidence, however, this man’s life was unsaveable

- and his death was not in anv wav attributable to thetreatment he received in hospital."