Given a passage with a context and an answer, construct a question on the basis of the information present in the passage. Construct the question in such a way that (i) it is unambiguous, (ii) it is answerable from the passage, (iii) its answer is unique (iv) it answer uses text phrases from the passage. Avoid creating questions that (i) can't be answered correctly without actually understanding the passage and (ii) uses the same words or phrases given in the passage.

Q: Context: Hyperoxia increases oxidative stress through the generation of reactive oxygen species and may therefore enhance inflammation in the lungs. The aim of this study was to investigate whether short term supplementary oxygen (28%) increases oxidative stress and inflammation in the airways by measuring 8-isoprostane and interleukin 6 (IL-6) concentrations in exhaled breath condensate.', 'Twenty three healthy subjects (12 men, mean (SD) age 48 (7) years) and 23 patients with chronic obstructive pulmonary disease (COPD; 15 men, mean (SD) age 56 (5) years) were studied. 8-isoprostane and IL-6 concentrations were measured by immunoassay.', 'Increased concentrations of 8-isoprostane and IL-6 were found in all subjects after breathing 28% oxygen for 1 hour. In healthy subjects the concentrations of 8-isoprostane and IL-6 were 10.9 (2.9) pg/ml and 4.9 (0.8) pg/ml, respectively, compared with baseline concentrations of 6.1 (1.3) pg/ml and 2.9 (0.6) pg/ml, and in patients with COPD the concentrations were 27.9 (3.1) pg/ml and 8.3 (1.2) pg/ml), respectively, compared with baseline concentrations of 18.9 (3.6) pg/ml and 6.3 (0.6) pg/ml. By contrast, breathing air through the same face mask for 1 hour had no significant effects on 8-isoprostane or IL-6 concentrations in normal subjects or those with COPD.
Answer: These findings suggest that short term supplementary oxygen may enhance oxidative stress and inflammation in the airways. Whether this happens with long term oxygen therapy needs to be determined.

A: Does supplementary oxygen in healthy subjects and those with COPD increase oxidative stress and airway inflammation?
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Q: Context: To assess the role of whole-body computed tomography (CT) for determining morphological suitability before multiorgan retrieval (MOR) in brain dead patients.', 'Fifty-one clinically brain dead patients (21 women, 30 men; mean age 61 year±15) were included in this prospective, single center study. All patients had CT angiography of the brain and whole-body CT examination. CT images were evaluated for the presence of morphological abnormalities of lungs, liver and other abdominal organs and presence of vascular anatomical variants. The results of CT examinations were compared to intraoperative findings observed during organ harvesting and/or the results of histopathological analysis of biopsy specimens. The impact of whole-body CT examination on the harvesting process was evaluated.', 'Ninety-five percent of vascular anatomical variants that were found intraoperatively were depicted on CT. CT density measurements predicted surgical finding of steatosis in 80% of patients. Whole-body CT changed the MOR strategy in 21/51 patients (41%) including 3 MOR cancellations and 8 grafts refusals, whereas organ harvesting was continued in 10 patients after histopathological analysis was performed.
Answer: Selection of potential graft donors using whole-body CT is reliable and improves graft selection during MOR.

A: Is simultaneous CT angiography and whole-body CT an effective imaging approach before multiorgan retrieval?
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Q: Context: Early laparoscopic cholecystectomy (LC) results in a shorter length of stay and acceptable conversion and complication rates when compared with antibiotic therapy plus interval LC or percutaneous cholecystostomy in patients admitted to a surgical service because of acute cholecystitis. However, actual practice does not conform to current evidence.', 'Retrospective cohort study.', 'Urban teaching hospital.', 'Data were abstracted from the medical records of all patients with acute cholecystitis admitted to the surgical service via the emergency department during 36 months (October 1, 2002, to September 30, 2005). Patients were divided into 5 groups on the basis of treatment received. Length of stay, duration of symptoms, major complications, and conversion rates were analyzed.', 'Of 173 patients with acute cholecystitis, 71 (41%) underwent early LC. Of 102 patients treated with antibiotic therapy alone (59%), 57 were discharged; antibiotic therapy was unsuccessful in 45 patients. Of the patients in whom antibiotic therapy was unsuccessful, 26 underwent late LC and 19 underwent percutaneous cholecystostomy. Interval LC was eventually performed in 55 patients who did not undergo surgery during the index admission. Length of stay was significantly shorter in the early LC group compared with the interval LC group (P < .001). Conversion rates were not statistically different for the 3 LC groups (early LC, 5.6%; late LC, 11.5%; and interval LC, 9.1%). The only biliary complication occurred in the interval LC group.
Answer: Early laparoscopic cholecystectomy resulted in a significantly reduced length of stay, no major complications, and no significant difference in conversion rates when compared with initial antibiotic treatment and interval LC. Despite these advantages, early LC is not the most common treatment for acute cholecystitis in practice.

A:
Is early laparoscopic cholecystectomy the preferred management of acute cholecystitis?
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