Detecting Acute Lung Rejection and Infection Following Heart-Lung Transplantation: DISCUSSION
A fall in FEV, and vital capacity (VC) led to transbronchial biopsy on 29 occasions for either infection or rejection. All the patients had symptoms at this time. On nine other occassions, the FEV, and VC were unchanged at a time of routine TBB and the histologic findings of the lung were normal. These patients did not have symptoms. The battery-operated pocket spirometer performed in these 15 patients without fault during the study and there was no change in calibration. From our experience we recommend that HLT recipients be instructed to record FEV, and VC daily and to contact the hospital when a fall of 10 percent or more occurs after a period of stable spirometry and persists for longer than two days.
In both acute rejection and opportunistic infection of the lungs, inflammatory cell infiltrates are found predominantly in the lung periphery. This is likely to affect compliance and this, we suspect, causes the comparable fall in both FEV! and VC with these complications. Indeed, TLC also falls. Change in Deo is more variable.
There were 22 occasions in six of the 15 patients where temporary falls in FEV, occurred without the development of symptoms. The fall was less than in histologically diagnosed infection and rejection and lasted for a shorter period despite no treatment being given. The cause of these changes is uncertain. It is unlikely to be technical as there was no evidence of calibration drift of the turbine spirometer. Rejection or infection sufficiently severe to alter lung mechanics is more likely to cause sustained falls in FEV, and VC if treatment is not given. Alternatively, the fluctuation of FEV, in particular, could reflect bronchial hyper- responsiveness. Bronchial hyperresponsiveness to methacholine and histamine is common in HLT recipients and appears to be unrelated to the presence of rejection. Indeed, a marked diurnal variation has been seen in some HLT recipients similar to that in asthma sufferers. As a result of these recent observations we now ask patients to record FEV, and VC on rising from bed in the morning so as to avoid the diurnal variation. Viagra Professional
Treatment of both infection or rejection is associated with a return of spirometry to normal (Fig 2). Spirometry can therefore be used to monitor efficacy of treatment. Chronic rejection, characterized by obliterative bronchiolitis, is associated with an irreversible fall in spirometry, severe airflow obstruction being predominant. Daily records show a progressive fall in FEV, without response to augmented immunosuppression (Fig 5). In this particular patient the diagnosis of chronic rejection was confirmed by histologic examination of an open lung biopsy specimen.
