Document b59Z6mZYEJkgYjwvR9Je6Gk33

BB 0 0 0 5 7 5 6 A: ' *t*; ~ ll ll l l !5 i ii. i i li li I n(i HAJtOLU V. LIDDLE 4c Oca Staphyiococcu\ aureui, despile the absence of that organism in cultures of the patient's sputum. Microscopic examination of the cyst wall revealed fibrous time Vtd chronic inflammation. There were maUpe healed necrotic foci and (he adjacent tusf showed severe brone hi olet tasis. There wm no frag ment of normal bronchial architecture in this cyst. These clinical and morphologic observations substantiate the diagnosis of post m/eefious pneumatocele in this patient. Although there is inadequate documen tation of this child's initial illness, the jothor beheves the evidence presented sup ports the conclusion that she had a chron ic ulh persisting post-infectious pneumato cele which is known to have existed for three and probably for six years H.FEhiNC 1 Watkins, E , J* and Hrjuno, A C.: *Tiw Management of Staphylococcic Lesioa Pneu matocele* by [ntraeavity Tube Drais^t,* J Thor Cordtov Surf, 36:642, 1956. 2 Saiiston, D G, Jk, Hopkins, E. H , Coou, It E and Bannitt, I L, Jr, : 'The Surgical Management of CompKcitaoni of Stapbylococ cal Pneumonia in Infancy and Childhood," J Thor Cardto v. Surg , 38'421, 1959. J fittiea, A M., Trrver, R W., Cuctsm, j A Schultix, C ano Millrr, D. F.: Httanhy^ coccal Pneumonia A Review of 21 Cntt,r New Engi J. Mod , 258*919, 1956 4 PoTTij W. J and RtKtft, W L.: "Differentia lion ol Congenita] Cysti of the Lung and Tbote Following Staphylococcic Pneumonia/1 AM A Arch. Sutg , 61: 684, 1950. 5 Willman, V L , Lewis, J E , Ja. and Han lon, C R..: "Staphylococcal Pneumonia: Sur gical Cunnderntioni in Cues of Infants and Children," Arch. Surg., 63:93, 1961 For reprints, please write Dr Liddle, Guihnc Clime, Sayre, Pennsylvania. ANNOUNCING THE 1964 ESSAY CONTEST The American College of Chest Physi cians is offering three cash awards to winners of the 1964 Essay Contest First prize is (500, Second prize (300, Third prize (200 Each winner will also receive a certificate A trophy will be presented to the med ical school attended by the first prize winner. This trophy will be inscribed with the name of the winner and the name of his school. The contest is open to undergraduate medical students throughout the world. Essays may be written on any phase of the diagnosis and treatment of chest dis eases (cardiovascular or pulmonary) Five copies of the essay must be sub mitted in English; length is optional. Contest doses on March IS, 1964. Application and further information may be obtained from the American College of Chest Physicians, 112 East Chestnut Street, Chicago, Illinois 60611, U.S.A. NO) GUf/fil i'i\0,,`i | l) t5<w^t=S op Te(i Che-ST 'Joe. 4r * i7-m cius) Asbestosis Sbum or the octsom oh Nature and Prevalence Gnumttu om Oocnratsonal Diseases of the Chest a ssasTOEta M a wniH bvumnarv diasasc k wVck ibruat is the dom inant reactMH M Ac prtrfafl reSKirm in the hutf Af mhmm B>rn. AaauTo* Asbestos is of mmmd ongia. Use name asbestos derives from the Grach word for unquenchable." TV term embraces at least 30 silicate compounds which charac teristically have e tbrous structure. Their chemical arastitlsrats include: slicon, mag nesium, iroa, Amine, manganese, alumi num and chromium in various molecular states and hydrated to different degrees. Of the 30 er aseee asbestiform minerals, onlv six have asrrent economic signifi ance. They are: chrysotik, crocidolite, amesite, lnrhnyhydite, tremoliie and aclinulite. ChrysoCde it a fibrous lorm of ser pentine, the other five are amphiboles. The major phjsiral properties of asbestos sie its incotnhaitibility, its facility to be -epanted into Nansenti of fibers, its un usual flexibility wad its high tensile strength Other valuable and characteristic prop erties include resistance to heat, to moisture wj to the corrosive action of acids. These Properties vary considerably with the different types of asbestos. The size and flexi bility of the then and some chemical at tributes of fArmnm are characteristics with medical iniplications Sources Canada, Russia, South Africa and Rho'lesta are the main producers of chrysotile. Crocidolite is found in South Africa, 'AusUllri, South America and Italy. Amo&ite a mined fa South Africa while anthophyl- is found in Finland, United States, New Zealand, China, Japan and India. Ashes- 1050 has been reported from alt these coun tries. The industrial uses ot asbestos arc in creasing steadily and now exceed 3,000 specific conditions in which asbestos serves uniquely as a protectant against excessive heat, cold and corrosion. There are, there fore, a multiplicity of circumstances under which asbestosis can be encountered. Processing of Asbestos Because asbestos is found both on or near the earth's surface as well as at con siderable depths below it, the ore can be recovered by open pit or underground mining. The fact that 15 to 20 tons of serpentine rock must be mined in order to produce 1 ton of usable asbestos fibers means that in many asbestos mining opera tions, workers are exposed to serpentine as well as to asbestos dust even to a ratio of 95 per cent to 5 per cent. Asbestos fibers are recovered by mechan ical milling consisting essentially of succes sive stages of crushing and separation by air screening. The fibers are further sep arated, cleaned, graded according to length and then bagged for shipment. The asbestos fibers are used afterwanh in the weaving erf fiber resistant textiles and in the manufacture of reinforced mold ed cement products where they are sub mitted to further mixture with other con stituents according to different specifica tions. Industrial Hygiene Aspect In determining the dust hazard, both the total count of asbestos partidrs* in the working environment and the prcsalenrc of fibers of different lengths should lie con sidered. It is generatlv accepted that the risk of contracting asbestosis is highest where a Pdrutlri uird in ibis contrxt includet fiWi* * 'V?. >;.; a.. .-.; lOQ greater proportion of the dust particles is fibrous and in those operations in which moat of the processing is done in the dry state. In spite of the fact that thr total durt exposure may Ire higher in the asbestos mining industry, the health hazard is more serious in the asbestos textile industry. The explanation for this is that in mining SO per cent to 95 per cent of the dust may be serpentine rock dust, which is biologically relatively inert The wet stage of the asbestos cement industry yields a low risk, hut the dry mix ing of asbestos with cement or dry cutting of finished asbestos products are sources of asbestos hazard. There is no agreement on safe limits (or asbestos dust and the best evidence for this it that several governmental agencies have recommended 5,000,000 asbestos particles (of any length) per cubic foot of air as the maximal allowable concentration, some industries have adopted as their standard 1.000.000 asbestos fibers of 5 microns and greater length per cubic loot, and a third group of hygienists considers a count of 10.000.000 total dust particles per cubic foot as a safe limit. Techniques of dust counting vary considerably and need to be standardized. The most practical meth od is the membrane filter device The most accurate but least practical methods are the thermal and electrostatic preci pitators. The Konimeler and Impinger methods are unreliable. Currently the value of the Tyn- I-/ Co I d aHometer and photoelectric methods are being explored al ,tl Si *i| ' i/t i m ^--) Medical Aspects ^ J (a) Toxicology: Asbestos is not currently considered a ,Um:c substance since it does not produce Systemic poisoning. Thus far, no distinc tive' blood or urine deviations base lietn -drtti led among workers exposed to asbes tos No minimum lethal dose has been rs- r .1 1 ^ I for iriw-s[ns (b) Allergy: Asbestos dust has not been shown to be allergenic, either in occupational groups or |p Mgerimcntal animals. (c) Pathogenesis: Two theories of causation have gained acceptance in different quarters. These are, respectively, mechanical irritation by asbes tos fibers and fibrogenicily of the protein capsule of the asbestos body. The mechanical irritation concept is supported bj the observations that fibrosis occurs most densely in the parts of the lungs where the respiratory movements are greatest, or where the lung impinges against other inlralhoracic structures; that grinding the fibers to less than 5 microns in length decreases their capacity to evoke fibrosis in experimental animals; and that a fibrous mineral containing no silicate causes pul monary fibrosis in experimental animals. The chemical theory postulates an un known fibrogenic agent which is released by disintegration of asbestos bodies. This theory takes into account the delayed de velopment and progressive nature of ashes(otic fibrosis, and is based on the assump tion that there may be a correlation be tween dosage of exposure and the elapsed time after exposure. coasist of asbestos proteinaceous capsule. Dm though indicative of ofertMs at access*rily diagnostic el Aabcstotic ftbroks May CMCtaUtU around focal lesions *uk M retire tuhorculoaii or a brunchjecurew. Thia loci um he kept in mind of asbestosis through I Heural plaques have hoot fertoMd by nurey observers in the Uafcod America, Canada, Finlaad, ~ South Africa. In maay perhaps even the majority of pleural plaque* do not p*MSM lesions of asbestosis ami cmMam an asbestos fibers. Some pUquw oddly cariy and are localized on the poriortl pleura leaving the visceral pleura MrtfceMd. After many years, however, Mmm by Ac pa rietal plaque can evoke a Imi the opposing visceral pleura. That phqirrs, though apparent on x-ray, ant aM mo- ruled with any disability. They Anidd, however, be distinguished hm fee aerious form of subjdeural fibrotii md kwi pleural mesothelioma, both of rignificant limitation of 'ions. Razholoot (d) Pathology: The principal pulmonary lesions include regional atelectasis, interstitial, mucosal anil focal fibrosis, and bronchialar fibrosis. Dis tortion, distention or stenosis of bromh1 and fine diffuse emphysema may be as sociated with the fibrosis and become in such instances additional factois in ibf genesis of the respiratory disability. P(n vascular fibrosis is also observed in mi*4 cases of asbestosis contributing significant!' to the development of cor pulmonale The disease process is dispersed throughout thr lungs, but the lesions may be more accet^ mated subpleuraily and at the base* ' both lungs where the amplitude of 1 The radiologic pattern t characterized by a ground |_ and sometimes a fine stippling. TW cardiac dlhouette may also be bhrttnd- If there **" been some concurrent capooret to dust other than asbestos (as in mkreag), the patttTn miy be much coarser. A Slagle stand*nl therefore does not apply. The I.L.O. radiographic classification ii quite unsuitaWc for grading the type or severity of ado-stasis. The complication* of asbestosis, I1. cou,sei have their own Artmctive rad'ulogic patterns. fouioiusT (hnnuetr function studies of the conventional breathing rmnemrnts is greater. No lotic (ibrusis has ever been found in 1 inidiaslina] Iwnph nodes. Many aheo^ SJlJtC's MU'. Cunt am aslieslos bodies " I ^ave not shown good correlation ''ten the radiologic signs, the intensity ^ oration of exposure and pathology disttd through biopsy or at necropsy. Arterial oxygen saturation may stay uorin advanced asbestosis. On the more often than not, desaturation may precede |ic manifestations. Deficient inn across the alveolocapillary-' ji may in some cases be the only *fc' finding. Impaired ventilation and pulmonary elasticity are often in advanced asbestosis. In some kt. of asbestosis, there is a long latent between the establishment of posiradiologic signs, the first demons!rabdity of physiologic disturbance and the oirimate clinical outcome of respiratory failure. Additional sequelae or complica1 may supervene to initiate the disabling e of the disease. Intercurrent factors, as aging or coincidental pulmonary refections, may upset the respiratory bal- Sequelae and Com plications Acute and chronic right-sided heart dis ease and progressive cardiorespiratory failore are the most frequent terminal sequelae of asbestosis. An amociatkm between asbesSssii and tuberculosis has never been prov- op eo conclusively by any statistical or epi- 'jv," demiologic investigation and has been dis- ' --^ proved in experimental animals. Active tu- -~~~i berculosis may heal and not become reacti- i--v vated despite continuous asbestos dust ex posure. In the medical literature, there are more articles favoring a positive relationship be- tween cancer of the lung and asbestosis than denying it. While it has been reported that there may be an enhanced prevalence of pulmonary neoplasia in some asbestos industries (e.g. crocidolite or amosite), or in some locations (e.g. South Africa, Eng land); this does not appear to apply for the ,J chrysotile industry in North America. This comment applies both with respect to intra- ; pulmonary new growths and to pleural _ mesothelioma. __ In contrast to other pneumoconioses, as- bestosis is relatively infrequently compli- > ' 1 cated by bronchitis, bronchopneumonia or *; COMMITTEE ON OCCUPATIONAL CHEST DISEASES pneumonia In far advanced asbeMiAis, asymptomatic noninflammatory bronchiec tasis may, however, occur at a result of distension of bronchi and brngkrhftjlc* by contraction of intervening fibfout wue Hypertrophic or obstructive pulmonary em physema is not j feature of aibestosis, Be tween zones of fibrosis, however, alveolar spaces may become distended and dittorted. This anatomic condition may be identified through biopsy or at necropsy, but is not usually associated with a clinically disabling equivalent Prevalence of Asbestosis Apart from inequalities of the dust ex posure in different industries, many other circumstances can explain the gieal varia tion in the alleged incidence of asbestosis Reports of prevalence range from 8 per cent to 77 per cent in different industries ui different countries. The criteria for the diagnosis of ashestesis are far from uniform. The application of different radiologic criteria, for instance, may significantly influence the incidence rate as reported by separate radiologists. The method of tabulating the cases is a factor. In the same industry, an incidence of 24 per cent among the workers exposed to the dust can become only 8 per cem when the same cases are diluted among the total number of employees of the whole industry The pathologist, who sees only deceased cases, or the consultant who re views chiefly problem cases, arc likelv to have more pessimistic views of the disease than the clinician, who has under his care both those who hemme ill and those who develop limited disease only or who may even escape the asliestotic reaction despite significant exposure. Even the more or less offuial statistics issued by different ('omfKiLsit ion Hoards have to be accepted with caution liefore being compared Often the Idx ral inurprrlation of the aggravating fai tor cIjusc, or the according of berirfil of the doubt and other s<h ial <onsideralions, will give impressions of incidence which ^ reconciled with authoritative medical 4^. ions. In order to have a prevalence rate which will be more representative and more eaact it would be necessary to collate the data which may be gathered from a anafi ran dom sampling of pathology of deceased asbestos workers. Even such a study would only yield data applicable to the industn of asbratfot dust may cause itching espe cially in zones of contact between clothing, wristbands, etc. This b due to Ruperficial penetration of coane (hK.Hfl has no clinical significance. BeOOft DKb by the BgQljpRatb Prevalence: John W G. HaNMR:OU Cartier. Roes K CJaiMerboae. figeM T. Diibow, G W. H. Scbepen, KcfhaM H. Inert aed Roy E Whitehead Peter A Theodos, Chairman, Committee on Occupational Diieaw of the Cheat * I in question and similar investigations would be needed for each type of industry. thesis have industritt. For reprinti, please write Dr. J W. G. Hannon, 628 Washington Trust Building, Washington, Pa The divergent and even the contradic tory opinions circulating on the different aspects of asbestosis and the numerous un HE INTERIM CLINICAL SESSION* answered questions have created an em barrassing confusion for many of those CM4JBGE OF GUEST PHYSICIANS concerned with the scientific and the prac tical problems of asbestosis. Differential Diagnosis Asbestosis can be simulated by any of the numerous varieties of diffuse inter stitial fibrosis. For diagnosis, precise infor mation is needed concerning the occupa tional exposure. When dealing with a group of industrial employees and when serial radiographs and clinical records art available, diagnosis may not be too diffi Dn Artkur C. ally Ram large quantities at , Wood In price* ten. They Raws surgery e|lnjH| with solutions as* tilled srater ee 8 | saline sotutlaa, mmi suits of Hits _ .Timas DURING CARDIOPULMONARY BYPASS ELIMINATING HEPARINIZED BLOOD 1 A Cooley, physiologic byof haparlnlsad. hemrUogom 1 types of yuay oxygenn- I a toehshw of ogaa heart associated with ibis technique of open heart surgery, renal hemodynamic changes eoacootltant to Otic technique have been compared with those seen fol lowing temporary cardiopulmonary bypass with fratfa homologous blood. A similar comparison has been mads of changes in blood viscosity during and following bypass. Plana electrolyte and both total body water and extracellular ftuld volume change! have been studied as have change* tn plasma hemogloblo levels during and following bypass The results of these studios would appear to offer further evidence that ibis technique of open heart surgery la superior to those employing pooled homologous blood Both experimental and clinical id their Implications die- cult. In isolation, asbestosis can often onh be recognized through biopay or at necropsy. The finding of asbestos bodies in the sputum is indicative only of prior exposure and not of asbestosis. Prevention Asbestosis can only be prevented be avoiding prolonged inhalation of high con centrations of asbestos particles. Aluminum inhalations are of no benefit, as with sib' tosis. Treatment No specific treatment exists. However tunsideraUlt Ixmefit may derive from treatmg vvmpioms or complications. It is better 10 keep aslicstotic subjects active and am bulant as long as feasible Prolonged inv muhibiv may lead to serious pulmonan lestriction 1 BRONCHIAL GLANDS Dr, Otto C. Un reads Maty Of 1 sad th* mucus oUa of the 1 The study was 1 ary emphy and In pukmovlU end with- hfce these he mr uUly ItkuN Patlaat with 1 The domestic ptg bronchial glands more nearly 1 do other animats, but narI ogUs In the mucosa. The bronchial glands that are generally larger than the normal In norms) subjects and In pulmonary em physema In man. the submucosal gland! show exten sive staining with PAS. stain which indicates an C"3 add or neutral mucopolysaccharide, (ewer cells and Oglands stain with Aldan blue which Indicates acid muoopolysaccharide. After pulmonary denervation, the pulmonary emphysematous bronchus shows e marked atro^ty of submucosal bronchial glands and the mueoaa and submucosal layer and a marked i` < i lessening of the Aldan blue staining material In addition, there Is the appearance of many goblei "i `i O -H m -I TJl In CT GASTRIC FREEZING in treatment of symptomatic hiatal hernia Cl. TwmlnMii) a paLienli -Hh lymptomallc Ma*" kanlt via at awlilthout associated peptic ulcer ,, treated by gastric (reeling after v ^Jaagensteen during the past ten40 evaluation of the clinical results followup period was presented Takooa Park, Maryland PTe-freexe evaluailon and selection o( these patients' for cryogenic surgery was presented along withal Illustrations o( some gross and microscopic changes seen In biopsy specimens of the mucosa The resulliT'y',-j obtained during this period would not seem tu *uj^ port the excellent results reported by other investi- vJ geton having smaller numbers of patterns D rj) k..ww rn `Portland. Oregon. November 30-December l, IMS Future tssuee of Dnrttti f jJ* Cb*u will contain fnmpleta manuscripts of many of these pspers mO