A Historical Footnote to Respiratory Therapy

currently believed in the United States, dating not from 1970,3 but at least from 19tH.' As Dalton et al3 point out , the T-piece principle was first described by Dr. Philip Ayre" (1902-1979), who told me that he thought of the idea following rupture of a child's lungs in the days before reducing valves were fitted to gas cylinders. The original device is now exhibited in the Department of Anaesthesia, Newcastle General Hospital, England , where he worked . As 1 recently discovered, the T-piece principle was used for oxygen therapy with cont inuous positive airway pressure in 1950,. and a modification of the original, rather crude diagram appeared in 1952.7 The oxygen T piece is sometimes called "the cigar" here because of the mist (smoke) that appears from its end when it is linked to a nebulizer. Finally, it is reassuring to note that our colleagues in the United States have at last accepted the overriding importance of muscle fatigue in failure to wean (er, liberate) the patient from mechanical ventilation, a problem many of us in Europe have recognized for over 30 years-perhaps even 40 years, since the poliomyelitis epidemic of 1952.' Of course, this letter won't change historical perceptions either. Alan Cilston, M.B ., London. England REFERENCES

FIGURE 1. Posteroanterior chest radiograph reveals occult asymptomatic FB lodged in left lower lobe . bronchoscopy, but 1 year later the patient coughed it up . Depending on the composition of the aspirated FB and its location, an FB may remain in situ without causing symptoms. Attempting to remove a suspected FB is appropriate;' however, observation may be reasonable, because of the rare occurrences of spontaneous expectoration. Mark Pinals, M.D ., Donald Pinals, M. D., john D. Tracy, M.D ., and Robert D. Brandstetter, M.D ., F.C .C .P., New Rochelle Hospital Medical Center, New Rochelle , New York REFERENCES

Jackson C, Jackson CL. Diseases of the air and food passages of foreign bod y origin . Philadelphia: WB Saunders Co , 1936 2 Limper AH, Prakash UBS. Tracheobronchial foreign bodies in adults. Ann Intern Med 1990; 112:604-Q9 3 Volpe BT, Brandstetter RD . Delayed pneumonia after aspiration of "das hboard" fragment. J Trauma 1985; 25:1173-74 4 Lillington GA, Ruhe RA, Peirce TH , Gorin AB. Removal of endobronchial foreign body by fiberoptic bronchoscopy. Am Rev Respir Dis 1976; 113:387-91

A Historical Footnote to Respiratory Therapy To the Editor: The thoughtful editorial on ventilatory weaning by Brand stetter and Tamarin,' which appeared in the June 1992 issue of Chest, is unlikely to change current usage . The term "wean ing" is much older than the 20 years they suggest-30 years at least'-and very probably much older even than that. Another point , the oxygen T piece also is much older than is

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Brandstetter RD , Tamarin F. Weaning is demeaning: it's time for liberation [editorial) . Chest 1992; 101:1488 Gilston A. The management of respiratory distress after cardiathoracic surgery. Thorax 1962; 17:139-45 Dalton B. Hallowell P, Bland JHL, Lowenstein E . A method of supplemental oxygen administration during weaning from mechanical ventilation. Anesthesiology 1970; 33:452-54 Gilston A. A tracheotomy T-piece. Lancet 1961; 1:1326 Ayre P. Endotracheal anesthesia for babies with special reference to hare-lip and cleft palate. Curr Res Anesth Analg 1937; 16:33033 Kottke FJ, Kubicek WG , Gullickson G, Stilwell GK. Problems of oxygen therapy. Bull Univ Minn Hospitals 1950; 21:455-64 Jensen NK. Recovery of pulmonary function after crushing injuries of the chest. Dis Chest 1952; 22:319-43 Lassen HCA. A preliminary report on the 1952 epidemic of poliomyelitis in Copenhagen with spec ial reference to the treatment of acute respiratory insufficiency. Lancet 1953; 1:37-9

Activation of Bone Marrow Eosinophils in Asthma 1b the Editor: Eosinophils are thought to be important inflammatory cells in asthma, especially late-phase asthmatic reaction .' Most eosinophils in asthma are activated in the airway! Regarding the genesis of tissue eosinophil accumulation, it is generally accepted that the recruitment of eosinophils is caused or modulated by chemotactic factors and cytokines, which are released from mast cells, TH2-type cells, and other inflammatory cells. Eosinophils can then be activated , and their survival can be prolonged by interleukin-.7' and granulocyte/macrophage colony-stimulating factor' in the tissue . There are few reports of activation of bone marrow eosinophils. In order to investigate the activation of marrow eosinophils, we perfonned an immunohistochemical study of the bone marrow obtained from a patient who died of a severe asthmatic attack. We used an eosinophil granule monoclonal antibody (EG2) as a marker of activated secreting eosinophils.S We found that a large number of immature eosinophils, which had a large nucleus with a large amount of cytoplasm and were proeos inophils, were stained by EG2 antibody (Fig 1). In contrast, in control bone marrow obtained from an autopsy case of apoplexy without asthma, only a few eosinophils CHEST. I 103 I 6 I JUNE, 1993

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