Objective: Inspiratory fall in intrathoracic pressure during a spontaneous breathing trial (SBT) may precipitate cardiac dysfunction and acute pulmonary edema. We aimed to determine the relationship between radiological signs of pulmonary congestion prior to an SBT and weaning outcomes. Methods: This was a post hoc analysis of a prospective cohort study involving patients in an adult medical-surgical ICU. All enrolled individuals met the eligibility criteria for liberation from mechanical ventilation. Tracheostomized subjects were excluded. The primary endpoint was SBT failure, defined as the inability to tolerate a T-piece trial for 30-120 min. An attending radiologist applied a radiological score on interpretation of digital chest X-rays performed before the SBT. Results: A total of 170 T-piece trials were carried out; SBT failure occurred in 28 trials (16.4%), and 133 subjects (78.3%) were extubated at first attempt. Radiological scores were similar between SBT-failure and SBT-success groups (median [interquartile range] = 3 [2-4] points vs. 3 [2-4] points; p = 0.15), which, according to the score criteria, represented interstitial lung congestion. The analysis of ROC curves demonstrated poor accuracy (area under the curve = 0.58) of chest x-rays findings of congestion prior to the SBT for discriminating between SBT failure and SBT success. No correlation was found between fluid balance in the 48 h preceding the SBT and radiological score results (ρ = −0.13). Conclusions: Radiological findings of pulmonary congestion should not delay SBT indication, given that they did not predict weaning failure in the medical-surgical critically ill population. (ClinicalTrials.gov identifier: NCT02022839 [http://www.clinicaltrials.gov/])

Keywords: Radiography; Pulmonary edema; Ventilator weaning.

Aim: To evaluate the performance of an SHM scheme (streptomycin, isoniazid, and ethambutol) in an outpatient clinic routine treatment for tuberculosis. Method: Seventy-eight patients with tuberculosis whose prior treatment with the RHZ scheme (six months of rifampicin, isoniazid, and pyrazinamide) had to be discontinued due to adverse effects, or who could not receive the RHZ scheme due to high risk for liver toxicity, were treated in the outpatient clinic with the 12 month SHM scheme from 1986 to 1994, in the city of Porto Alegre, Rio Grande do Sul, Brazil. Results: Three patients (3.8%) required a scheme change due to toxicity. In the remaining 75 patients, 58 (77.3%) were cured, eight (10.7%) withdrew, five (6.7%) presented failure, and four (5.3%) died. Theoretical cure rate, which is the percent of cure of patients who regularly followed the treatment, was 95.3%. Adverse reactions were seen in 32 patients (41%), the most frequent being vestibular damage in 18 patients (23.1%). Results were compared to those obtained in the same outpatient clinic with the 12 month RHM scheme (rifampicin, isoniazid, and ethambutol), and with the six month RHZ scheme. Conclusion: The SHM scheme may be recommended as an alternative for the treatment of tuberculosis whenever the RHZ scheme cannot be indicated.