Because the purpose of the P-V measurements was to study surface elastic forces in the lung, determination of the inflation limb of the P-V relationships would have provided very useful information regarding the opening pressure and the hysteresis phenomena. Accurate determination and interpretation of P-V measurements in this study are of critical importance because they represent the only difference among various groups in the study. HAMID SAHEBJAMI, M.D. Department of Veterans Affairs Medical Center Cincinnati, OH

1. Lamm WJE, Albert RK. Surfactant replacement improves lung recoil in rabbit lungs after acid aspiration. Am Rev Respir Dis 1990; 142:1279-83.

From the Authors: We thank Dr. Sahebjami for his interest in our article describing the effects of surfactant replacement in the setting of the HCl aspiration model of acute lung injury (1). Weelected to degas the lungs so that the subsequently determined lung pressure-volume (P-V) relationships could be obtained with knowledge of the absolute lung volumes. Weagreethat inhomogeneous opening pressures might have been present, hence we presented data collected only on the deflation limb. We know of no reason why P-V curves of the control and HCltreated lungs cannot be compared as long as absolute lung gas volume and the volume of surfactant instilled are known. As stated, TLC was defined as that lung volume present at alveolar pressures of 25 and 40 em H 2 0 in the in vitro and in vivo studies, respectively. In absence of surfactant, all of the lung volume would represent air. When surfactant was added, some of the lung was filled with liquid such that the lung-gas volume would underestimate the true degree of lung distension (although only a 1-4070 correction was necessary). Our P-V curves did indeed reach a plateau in both the in vitro and in vivo studies. The scales used on the figures were selected to expand the graphs and facilitate comparison of the data. Our data were normalized to the percent TLC by constructing P-V curves in to-ml volume steps, connecting the points with straight lines, and then readingthe appropriate pressure for each percent TLC. We agree that interesting information might be present in the inflation limbs of our P-V data. However, for the very reasons alluded to by Dr. Sahebjami, the deflation limb is the one most classically used to describe lung mechanics. We also.agree that the method used for determining the P-V relationships is critical to the interpretation of our study. Accordingly, the technique weemployed was carefully considered and represents the most accurate one available. WAYNE LAMM


M.D. University of Washington Medical Center Seattle, WA RICHARD


1. Lamm WJE, Albert RK. Surfactant replacement improves lung recoil in rabbit lungs after acid aspiration. Am Rev Respir Dis 1990; 142:1279-83.

scale, controlled, prospective studies is inconsistent (1). Furthermore, Mycobacterium tuberculosis infections may be difficult to detect by the tuberculin test in populations where nonspecific tuberculin sensitivity (induced by BCG) is frequent. In Austria, general BCG vaccination of the newborn was introduced in 1952. At the end of 1989, it was recommended to restrict vaccination to babies with an "elevated risk of infection with tuberculosis." The main reason for abandoning the practice of general BCG vaccination of the newborn was a report presented to the vaccination committee of the Federal Board of Health, concerning 14 cases of severe complications after vaccination between 1970 and 1986. In Austria, BCG vaccine is ordered directly by the ministry of health. From 1980 to 1989, BCG sec Berna vaccine (strain Kopenhagen, 0.1 ml administered intradermally) was used. In 1990,however, due to the cost-benefit risk, this vaccine is no longer available from the Austrian distributor. The reasons given were the uncertainty of demand, in view of the introduction of restricted vaccination, as well as the (costly and time-consuming) official batch control tests introduced in 1989. Since March 1990, 60,000 doses of BCG vaccine Merieux (strain Kopenhagen, 0.1 ml administered intradermally) wereordered from another source. Within a surprisingly short period of time the entire batch had been distributed to physicians. In 1990, no reports of undesirable side effects reached the distributor of this vaccine. Because of a subsequent shortage of supplies from August 1990 onward, 7,540 ampoules of BCG Pasteur i.d. vaccineweredistributed (Pasteur strain, 0.05 ml given intradermally). Because of the occur. reneeof suppurative lymphadenitis in vaccinated newborns, the product was withdrawn from the market by official order from November 28, 1990.Apart from the increased reactogeneity ofthe Pasteur strain, erroneous application (0.1 ml instead of 0.05 ml) was also held responsible for the numerous side effects, for which, by March 15, 1991, 63 children had received surgical treatment at the University Hospital, Innsbruck. Of 659 babies vaccinated at the University Hospital, (department of obstetrics), 28 (4.2070) underwent surgery. At the present time, no BCG vaccine is available in Austria. The recommendation of vaccinating infants at high risk has also been cancelled. According to the World Health Organization, all complaints received from different countries concerning outbreaks of suppurative lymphadenitis in the last 20 yr were connected with a change of vaccine (2). This most recent outbreak of lymphadenitis associated with BCG vaccination also substantiates that the Pasteur strain is more reactogenic than the Kopenhagen strain. FRANZ ALLERBERGER, M.D. Federal Public Health Laboratory Innsbruck, Austria

1. Houston S, Fanning A, Soskolne C, Fraser N. The effectiveness of bacillusCalmette-Guerin (BCG) vaccination against tuberculosis. A case-control study in Traty Indians, Alberta, Canada. Am J Epidemiol1990; 131:340-8. 2. Anonymous. Lymphadenitis associated with BCG immunization. Wkly Epidem Rec 1988; 50:381-3.



To the Editor: Bacillus Calmette-Guerin (BCG) vaccination against tuberculosis has been used around the world for 70 yr; yet its efficacy in large-

Mortal complications accompanying Nd-YAGlaser photoresection (LPR) of endobronchial lesions include systemic air embolism, hemorrhage from either the lesion itself or from laser induced perforation of disrupted "normal" vascular structures, and fire. Inadvertent airway perforation leading to mediastinal emphysema is another potential major complication. Distorted mediastinal anatomy produced by resectional lung surgery, tumor infiltration, and radiation therapy contribute to such complications during LPR. Combination of distortion of the anatomy and perforation of air-


469 Because the purpose of the P-V measurements was to study surface elastic forces in the lung, determination of the inflation limb of the P-V relat...
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