Effect of Additional 1 hour T-piece Trial on Weaning Outcome to the Patients at Minimum Pressure Support / 결핵

BACKGROUND: Extubation is recommended to he performed at minimum pressure support (PSmin) during the pressure support ventilation (PSV). In field, physicians sometimes perform additional 1 hr T-piece trial to the patient at PSmin to reduce re-intubation risk. Although it provides confirmation of patient's breathing reserve, weaning could be delayed due to increased airway resistance by endotracheal tube. METHODS: To investigate the effect of additional 1 hr T-piece trial on weaning outcome, a prospective study was done in consecutive 44 patients who had received mechanical ventiIation more than 3 days. Respiratory mechanics, hemodymic, and gas exchange measurements were done and the level of PSmin was calculated using the equation (PSmin=peak inspiratory flow rate x total ventilatory system resistance) at the 15cm H2O of pressure support. At PSmin, the patients were randomized into intervention (additional 1 hr T-piece trial) and control (extubation at Psmin). The measurements were repeated at PSmin. during weaning process (in cases of intervention), and after extubation. The weaning success was defined as spontaneous breathing more than 48hr after extuintion. In intervention group, failure to continue weaning process was also considered as weaning failure. RESULTS: Thirty-six patients with 42 times weaning trial were satisfied to the protocol Mean PSmin level was 7.6 (+/-1.9)cm H2O. There were no differences in total ventilation times (TVT), APACHE III score nutritional indices, and respiratory mechanics at PSmin between 2 groups. The weaning success rate and re-intubation rate were not different between intervention group (55% and 18% in each) and control group (70% and 20% in each) at first weaning trial. Work of breathing, pressure time product, arid tidal volume were aggravated during 1 hr T-piece trial compared to those of PSmin in intervention group (10.4+/-1.25 and 1.66+/- 1.08 J/L in work of breathing)(191+/-232 and 287+/-217cm H2Os/m in pressure time product) (0.33+/-0.09 and 0.29+/-0.09 L in tidal volume) (P<0.05 in each). As in whole, TVT, and tidal volume at PSmin were significantly different between the patients with weaning success (246+/-195 hr, 043+/-0.11 L) and the Those with weaning failure (407+/-248 hr, 0.35+/-0.10L) (P<0.05 in each). CONCLUISON: There were no advantage to weaning outcome by addition of 1 hr T-piece trial compared to prompt extubation to the patient at PSmin.

Clinical Study on Thoracic Actinomycosis / 결핵

BACKGROUND: Actinomycotic infection is uncommon and primary actinomycosis of the lung and chest wall huts been less frequently reported. This disease may present as chronic debilitating illness with radiologic manifestation simulating lung tumor, pulmonary infiltrating lesion or chronic suppuration Diagnosis of choice was not definded yet and role of bronchoscopy on diagnosis was not described yet. METHODS: From 1989 to 1998, we experienced 17 cases of thoracic actinomycosis. We have reviewed the case notes of 17 patients with thoracic actinomycosis. The mean age at presentation was 53 +/- 13 years, 11 were male. RESULTS: Cough, hemoptysis, sputum production chest pain and weight loss were the commonest symptoms. The mean delay between presentation and diagnosis was 6.6 +/- 7.8 months. There were six patients who presented with a clinical picture of a suppurative lesion and eleven patients were suspected of having primary lung tumor initially. In no cases was made an accurate diagnosis at the time of hospital admission Associated diseases were emphysema (1 case), bronchiectasis (2 cases) and tuberculosis (2 cases). Bronchoscopic findings were mucosal swelling and stenosis (n=4), mucosal swelling, stenosis and necrotic covering (1=2), mass (n=3), mass and necrotic covering (n=1) and normal(n=6). Radiologic findings were mass lesion(n=8), pneumonitis(n=3), atelectasis(n=3), pleural effusion (n=2), and normal(n=3), Final diagnosis was based on percutaneous needle aspiration and biopsy (n=3), bronchoscopic biopsy specimens (n=9), mediastinoscopic biopsy (n=1) and histologic examination of resected tissue in the remaining patients(n=4) who received surgical excision Among 17 patients, 13 were treated medically and the other 4 received surgical intervention followed by antibiotic treatment Regarding the surgically treated patients suspected malignancy is the most common indication for operation. However, both medically and surgically treated patients achieved good clinical results. CONCLUSION: Thoracic actinomycosis is rare, but should still be considered in the differential diagnosis of a chrinic, localized pulmonary lesion Thoracic actinomycosis may co-exist with pulmonary tuberculosis or lung cancer. If the lesion is located in the central of the lung, the bronchoscopy is recommanded for the diagnosis.