Faculty Bibliography

BACKGROUND: There is no noninvasive method to rule out pulmonary embolism when the clinical suspicion for pulmonary embolism is high. We did a prospective observational study to determine the negative predictive value of spiral computed tomography (CT) in this situation. METHODS: We performed spiral CT scans of the thorax in consecutive patients with high clinical suspicion of pulmonary embolism with intermediate or low probability ventilation-perfusion scans. Patients with negative or indeterminate spiral CT results had conventional angiography at the discretion of the attending physician. Only patients with positive spiral CT results or positive conventional angiograms were treated. All patients were observed for 6 months for evidence of venous thromboembolic disease. Clinical outcome without treatment or the results of conventional angiography were used as reference standards. False-negative results were defined as a negative spiral CT with a positive conventional angiogram or any diagnosis of venous thromboembolism within 6 months. RESULTS: Among the 103 patients who were studied, spiral CT scans were positive in 22 patients, indeterminate in 10 patients, and negative in 71 patients. Twenty-seven (26%) patients had pulmonary embolism by clinical outcome, including 3 of the 71 patients with negative spiral CT scans and 2 of the 10 patients with indeterminate scans. A negative spiral CT result had a likelihood ratio of 0.12 (95% confidence interval [CI]: 0.04 to 0.35) with a negative predictive value of 96% (95% CI: 88% to 99%). Using conventional angiography only as the reference standard, a negative spiral CT result had a likelihood ratio of 0.08 (95% CI: 0.02 to 0.31) and a negative predictive value of 93% (95% CI: 77% to 98%). CONCLUSIONS: Spiral CT has a high negative predictive value for pulmonary embolism and may replace conventional angiography in the workup of pulmonary embolism. Patients with indeterminate spiral CT results should be considered for conventional angiography

STUDY OBJECTIVE: Patients with symptomatic malignant pleural effusion are usually treated with large-bore chest tube placement and pleurodesis requiring > or = 3 days of hospitalization. We sought to demonstrate the feasibility of ambulatory drainage and sclerosis using a small-bore pigtail catheter in patients with malignant pleural effusions. We reasoned that this approach would improve symptoms and quality of life at a reduced cost. METHODS: A 14F pigtail catheter was percutaneously inserted into the pleural space and connected to a closed gravity-drainage bag system. The patients were instructed in the use of the drainage system and discharged to return for sclerosis with 4 g of talc after the drainage was < 100 mL/24 h. Patients were graded for dyspnea and performances status using the Eastern Cooperative Oncology Group score (ECOG) and baseline and transitional dyspnea index score (BDI-TDI) before tube placement and again at 30 days. Radiographic response was graded as total response, partial response, or failure. Telephone follow-up was initiated when the patient could not return for evaluation. RESULTS: Ten ambulatory women, ages 41 to 79 years, were enrolled. The chest tube was left in place from 1 to 10 days, draining a mean of 2,956 mL (1,685 to 6,050 mL). Only two patients were unable to undergo sclerosis owing to catheter dislodgment and minimal drainage. Six reported symptomatic improvement at 30 days confirmed by TDI and ECOG scores in four of six. One with a prior history of a lobectomy was found to have a chylous pleural effusion and experienced a hydropneumothorax, for which sclerosis was unsuccessful. One died in hospital on day 26 after sclerosis despite radiographic resolution. Of the four patients who had improved dyspnea and functional status by TDI and EGOG scores, radiographic response was complete in three and partial in one. Two of the six were not able to return for follow-up because of weakness but reported improvement by telephone inquiry. CONCLUSION: Ambulatory sclerosis of malignant effusion using a small-bore catheter is a feasible alternative to inpatient sclerosis with a large-bore chest tube, especially in patients with strong preferences for outpatient care