Continuous Positive Airway Pressure during Bronchoalveolar Lavage in Patients with Severe Hypoxemia / 결핵

BACKGROUND: A bronchoalveolar lavage(BAL) is useful in diagnosing the etiology of bilateral pulmonary infiltrations, but may worsen the oxygenation and clinical status in severely hypoxemic patients. This study assessed the safety and efficacy of the continuous positive airway pressure(CPAP) using a conventional mechanical ventilator via a face mask as a tool for maintaining the oxygenation level during BAL. METHODS: Seven consecutive patients with the bilateral pulmonary infiltrates and severe hypoxemia (PaO2/FIO2 ratio

Continuous Positive Airway Pressure during Bronchoalveolar Lavage in Patients with Severe Hypoxemia / 결핵

BACKGROUND: A bronchoalveolar lavage(BAL) is useful in diagnosing the etiology of bilateral pulmonary infiltrations, but may worsen the oxygenation and clinical status in severely hypoxemic patients. This study assessed the safety and efficacy of the continuous positive airway pressure(CPAP) using a conventional mechanical ventilator via a face mask as a tool for maintaining the oxygenation level during BAL. METHODS: Seven consecutive patients with the bilateral pulmonary infiltrates and severe hypoxemia (PaO2/FIO2 ratio

Evaluation of Parameters of Gas Exchange During Partial Liquid Ventilation in Normal Rabbit Lung / 결핵

BACKGROUND: The opitmal ventilator setting during partial liquid ventilation(PLV) is controversial. This study investigated the effects of various gas exchange parameters during PLV in normal rabbit lungs in order to aid in the development of an optimal ventilator setting during PLV. METHODS: Seven New-Zealand white rabbits were ventilated in pressure-controlled mode with the following settings; tidal volume(VT) 8ml/kg, positive end-expiratory pressure(PEEP) 4cmH2O, inspiratory-to-expiratory ratio(I:E ratio) 1:2, fraction of inspired oxygen(F1O2) 1.0. The respiration rate(RR) was adjusted to keep PaCO2 between 35~45mmHg. The ventilator settings were changed every 30 min in the following sequence : (1) Baseline, as the basal ventilator setting, (2) Inverse ratio, I:E ratio 2:1, (3) high PEEP, adjust PEEP to achieve the same mean inspiratory pressure (MIP) as in the inverse ratio, (4) High VT, VT 15ml/kg, (5) high RR, the same minute ventilation(MV) as in the High VT. Subsequently, the same protocol was repeated after instilling 18ml/kg of perfluorodecalin for PLV. The parameters of gas exchange, lung mechanics, and hemodynamics were examined. RESULTS: (1) The gas ventilation(GV) group showed no significant changes in the PaO2 at all phases. The PaCO2 was lower and the pH was higher at the high VT and high RR phases(p<0.05). No significant changes in the lung mechnics and hemodynamics parameters were observed. (2) The baseline PaO2 for the PLV was 312+/-113mmHg. This was significantly lower when decreased compared to the baseline PaO2 for GV which was 504+/-81mmHg(p=0.001). During PLV, the PaO2 was significantly higher at the high PEEP(452+/-38mmHg) and high VT(461+/-53mmHg) phases compared with the baseline phase. However, it did not change significantly during the inverse I:E ratio or the high RR phases. (3) The PaCO2 was significantly lower at high VT and RR phases for both the GV and PLV. During the PLV, PaCO2 were significantly higher compared to the GV (p<0.05). (4) There were no important or significant changes in of baseline and high RR phases lung mechanics and hemodynamics parameters during the PLV. CONCLUSION: During PLV in the normal lung, adequate VT and PEEP are important for optimal oxygenation.

Predictors of drug-resistance in patients with pulmonary tuberculosis / 결핵

BACKGROUND: The drug-resistant tuberculosis has recently decreased in Korea, but it is still one of the major obstacles in the treatment of pulmonary tuberculosis. Unfortunately there are no reliable ways to figure out the drug sensitivity pattern of the M. tuberculosis in the starting point of treatment. At least several months which is critical for the success of treatment have to be passed away before getting the report of drug-sensitivity test. The aim of this study was to find out the clinical and radiological parameters that make it possible to predict the drug-resistant pulmonary tuberculosis and to make a correct decision on the antituberculosis drug regimens. METHOD: We studied 253 pulmonary TB patients with sputum and/or bronchial washing fluid culture-positive diagnosed at the Chung-Ang University Young-San Hospital in the period of 1989-1994. The differences in the clinical and raiological variables between the drug-sensitive and the drug-resistant tuberculosis patients were evaluated. RESULTS: In 66 out of 253 patients(26.1%), drug resistant tuberculosis to at least one antituberculosis drug were found. Patients with retreatment showed higher resistance rate than those with initial treatment (30/69,43.5% vs 36/184, 19.5%, p<0.01). Patients with cavitary TB showed higher resistance rate than those with non-cavitary TB( (24/54, 44.4% vs 42/199, 21.1%, p<0.05). Among patients with initial treatment, those with far-advanced TB showed a higher drug resistance rate than those with minimal lesion(9/23, 36.9% vs 10/82, 12.5%, p<0.05). Patients with culture positive only in the bronchial washing fluid showed lower resistance rate than those with sputum culture positive(7/63, 11.1% vs 59/190, 31.1%, p<0.05) CONCLUSION: Prior treatment history for pulmonary tuberculosis, the presence of cavity & far advanced tuberculosis in the radiologic exam, sputum rather than solely bronchial washing culture positivity would be the related factors to the drug resistance. So in the patients with such characteristics, it is needed to try to find out the drug sensitivity pattern of the infecting tuberculosis organism as soon as possible.