The Noninvasive Ventilation Outcomes (NIVO) score: prediction of in-hospital mortality in exacerbations of COPD requiring assisted ventilation.

INTRODUCTION: Acute exacerbations of COPD (AECOPD) complicated by acute (acidaemic) hypercapnic respiratory failure (AHRF) requiring ventilation are common. When applied appropriately, ventilation substantially reduces mortality. Despite this, there is evidence of poor practice and prognostic pessimism. A clinical prediction tool could improve decision making regarding ventilation, but none is routinely used. METHODS: Consecutive patients admitted with AECOPD and AHRF treated with assisted ventilation (principally noninvasive ventilation) were identified in two hospitals serving differing populations. Known and potential prognostic indices were identified a priori. A prediction tool for in-hospital death was derived using multivariable regression analysis. Prospective, external validation was performed in a temporally separate, geographically diverse 10-centre study. The trial methodology adhered to TRIPOD (Transparent Reporting of a Multivariable Prediction Model for Individual Prognosis or Diagnosis) recommendations. RESULTS: Derivation cohort: n=489, in-hospital mortality 25.4%; validation cohort: n=733, in-hospital mortality 20.1%. Using six simple categorised variables (extended Medical Research Council Dyspnoea score 1-4/5a/5b, time from admission to acidaemia >12 h, pH <7.25, presence of atrial fibrillation, Glasgow coma scale ≤14 and chest radiograph consolidation), a simple scoring system with strong prediction of in-hospital mortality is achieved. The resultant Noninvasive Ventilation Outcomes (NIVO) score had area under the receiver operating curve of 0.79 and offers good calibration and discrimination across stratified risk groups in its validation cohort. DISCUSSION: The NIVO score outperformed pre-specified comparator scores. It is validated in a generalisable cohort and works despite the heterogeneity inherent to both this patient group and this intervention. Potential applications include informing discussions with patients and their families, aiding treatment escalation decisions, challenging pessimism and comparing risk-adjusted outcomes across centres.

Lung transplantation outcome in cystic fibrosis patients with previous pneumothorax.

BACKGROUND: High perioperative mortality that results from hemorrhage from pleural adhesions was reported in the early experience of heart-lung transplantation. This led to previous pleural procedures becoming a relative/absolute contraindication to transplantation in some centers, despite the advent of bilateral lung transplantation. Has this lead to a more conservative approach to pneumothorax management in patients with cystic fibrosis (CF)? And what is the effect of previous pleural procedures on surgical outcome of lung transplantation? METHODS: We reviewed 3 groups of patients transplanted at this center from 1989 to 2002, matched for year of lung transplantation. Group A comprised 16 patients with CF with a history of previous pneumothorax with or without pleural procedure. Group B comprised 16 patients with CF with no history of pneumothorax. Group C comprised 16 noninflammatory/nonbronchiectatic patients with no history of pneumothorax. Measured outcomes included blood products provided intraoperatively; operation and cardiopulmonary bypass times; postoperative hemorrhage; times to extubation, discharge from the intensive care unit and hospital discharge; forced expiratory volume at 1 second at 6 months; 30-day mortality; pleural adhesions graded descriptively; and previous pneumothorax management (Group A only). There were 35 pneumothorax episodes in the 16 patients in Group A. Nine episodes were managed with observation alone. Nine patients required invasive management, 25 chest drains were placed, 3 patients received medical pleurodesis, and 2 underwent thoracic surgical intervention. RESULTS: No significant difference was observed between the 3 groups regarding blood products intraoperatively or duration of procedure. Pleural adhesions found at operation were significantly more in Group A, with dense adhesions found only in Group A (p<0.05). Group C was significantly more likely to be free from adhesions, with 13 patients clear (p<0.01 Group C vs Group A, Group C vs Group B). No statistically significant difference was found in the other measured parameters. CONCLUSIONS: Pneumothorax is treated conservatively in a potential lung transplant population. Patients with CF and previous pneumothorax with or without pleural procedures undergoing lung transplantation have dense pleural adhesions; however, this does not affect surgical outcome significantly. Patients with emphysema, fibrosing alveolitis, or obliterative bronchiolitis were significantly more likely to be free of pleural adhesions, suggesting that the inflammatory/chronic infective component of CF independently contributes to the increased pleural adhesions. Previous pleural procedures for pneumothorax should not be considered a contraindication in the assessment of suitability for lung transplantation.