Prediction results of lvrs on the other carat

San Francisco National Emphysema Treatment Trial (net) was designed to compare the results of emphysema after maximum medical therapyalone or in combination with a reduction of lung surgery (LVRS). [1] However, a large, ongoing clinical trials have provided valuable knowledge about other aspects of emphysema, researchers have recognized at the recent annual meeting of the American thoracic society. Five-year study focused on patients with severe airway obstruction and hyperinflation, and computed tomography (CT) evidence of emphysema. By the end of the study, NETT researchers intend received 2,500 such patients to treatment in 17 primary clinical research centers and over 300 satellite facilities, with approximately 3000 patients have been shown to date, about 1000 patients were randomized. The exemptions must be nonsmokers or be ready to quit. During the initial phase prior randomisation all patients undergo a thorough medical examination. Patients then receive six to 10 weeks of treatment, which includes the maximum medical therapy and participation in pulmonary rehabilitation. At randomization, half of the patients assigned to continue on this regime and the other half go LVRS, or medium sternotomy or video-assisted thoracic surgery. Patients in each hand, you will receive an additional eight weeks of pulmonary rehabilitation, in addition, they were asked to return for follow-up at 6, 12, 24 and 36 months. Provocative

CONCLUSIONS Since SUB-STUDY One

The most interesting results of the NETT today was

demonstrated in a small subgroup of study: Leisure hemodynamic

in emphysema patients are not as bad as can seem at

initial cardiac catheterization, which often show moderate to severe >> << pulmonary hypertension. This conclusion is based on

sub-study of 107 patients with severe emphysema, 67 with yaks

eventually were included in the NETT. Results are presented

Steven M. Scharf, MD, one of the main NETTs >> << investigators and head of light research

Long Island Jewish Medical Center in New Hyde Park ,

New York. [2]

patients in sub-study were aged 51 to 78 years, been a standard right heart catheterization to measure cardiac output and pulmonary artery (PA), right atrial, right ventricular systolic and diastolic pressure. Fast thermistor catheter was used so that the forward right-left ventricular ejection fraction can also be measured. Left ventricular ejection fraction was determined with a closed blood pool studies and several private scan acquisition. Twenty-five patients also underwent esophageal pressure measurement back within a week or so, cardiac catheterization, and investigators suspected that results were representative of the overall study population support. It is possible to calculate transpulmonary pressure, said Dr. Scharf. Hemodynamics is not as it seemed, patients had mean arterial pressure of oxygen (rO2) 67 mm Hg, mean forced expiratory volume in one second (FEV1) of 27 provided, and the average score of emphysema in 17 (of maximum 24) on CT. They were neither hiperkapnicheskoy not hypoxic, said Dr. Scharf. However, their emphysema was difficult, at least in some segments of the lungs, he said. Central PA systolic pressure was almost 38 mm Hg, clear high and average PA diastolic pressure was about 21 mm Hg. PA pressure secondary to an average 26 mm Hg. Thus, these patients were in pulmonary hypertension group, said Dr. Scharf. In fact, pulmonary hypertension was assessed in 75 moderate to severe for 16 years. After the PA systolic pressure was subtracted transmural, however, only 28 patients entered the group of moderate and not judged to severe pulmonary hypertension. A similar picture emerged when the researchers assessed the severity of pulmonary hypertension when you average PA, and then subtracted the end expiratory esophageal pressure. This phenomenon also occurred in pulmonary capillary wedge pressure (TZLK), which originally was slightly to moderately elevated in 53 patients and significantly increased about 8. When [we] is subtracted from the pleural pressure, none of the patients had a wedge pressure above 20, and only 12 were mild to moderate high blood pressure wedge, Dr. Scharf said. Correlations were intriguing sub-study also found some interesting correlations. PA pressure increased as the average daily rest rO2 fell, for example, although Dr. Scharf described this ratio is not very tight. Much tighter correlation emerged between PA pressure and medium pressure PCW. It was characterized by 7 mm Hg increase in the former for every 10 mmHg increase in the latter. There was also a strong correlation between CT scorean emphysema, the severity score, based on serial power scansand diffusion of light. But none of these variables predicted PA pressure, said Dr. Scharf. From the data shown

in this sub-study, Dr. Scharf has formed the following conclusions:

Although pulmonary hypertension is a common >> << In emphysema patients, it is not when the transmural

pressure. Right and left ventricular dysfunction is systolic

not common in emphysema. Transpulmonary pressure and TZLK are important factors

pressure PA, while only mild hypoxemia precursor. Estimates of parenchymal destruction, not intellectual >> << value. PREDICTION LVRS results of CT Other

south of the NETT study examines whether the basic

CT results can predict the outcome of patients after LVRS. [3]

This sub-study was described by J. Fernando Martinez, MD,

also principal investigator and associate professor of internal medicine

at the University of Michigan in Ann

Arbor. Two-thirds of emphysema patients who undergo LVRS have significantly better lung function in early postoperative period, Dr. Martinez said, although only 10 still show improvement four years ago. The pace of decline during this time quite heterogeneous, however, some patients maintain improvement in lung function over several years or more, while in others, reduced lung function much earlier. Will possibly predictor of response to LVRS this regard would be helpful in deciding if this procedure is worth the risk, said Dr. Martinez. With the assistance of other researchers, he began to develop a forecaster with the data earlier, smaller study of CT emphysema patients. For example, one study showed decreased volume of emphysema after LVRS and showed that the degree of changes of emphysema may help predict the outcome. Other studies have shown that the greatest short-term improvement of FEV1 after LVRS occur in patients with the most heterogeneous model CT disease. By combining these data, Ella Kazeruni, MD, a colleague of Dr. Martinez, made practical measures heterogeneity of emphysema on the basis of quantitative CT CT scanningthe ratio (CTR). This ratio compares the upper and lower lobe volume of emphysema, as they appear on the baseline (preoperative) CT.

CTR 1 indicates homogeneous disease, high clickthrough rate (from 2 to 4) indicate heterogeneous emphysema. Dr. Martinez, Kazeruni, and employees of CTR used prospectively to emphysema patients observed at medical center for NETT. They found that high CTR with a high positive predictive value for short and long term improvement of FEV1 after LVRS, but CTR 1 is not very predictive of postoperative FEV1 improvement. However, some patients with homogeneous emphysema can benefit from LVRS Dr. Martinez added. The basic lasix 20 mg inspiration of conductivity may be a better predictor of surgical treatment in this group that may have more respiratory component of the illness and therefore not be expected to show much improvement of FEV1 after surgery, he said, referring to the work of other researchers. Because Dr. Martinezs method of forecasting the results of LVRS based on a small number of patients, most of which were predominantly upper lobe involvement, NETT will examine these issues in cooperation between the clinical research center and image analysis at the University of Iowa, led by Eric Hoffman, PhD . These researchers will be considered qualitative and quantitative measurements of emphysema in a large number of patients is characterized by strict, clearly defined methods. Timothy

Begany References 1. National Emphysema Treatment Trial Research Group. Rationale and design of the National Emphysema Treatment Lung

Trial (net): prospective randomized trial of lung volume reduction surgery <<. Thoracic >> J Cardiovasc Surg. 1999, 118:518-528. 2. Scharf SM. Hemodynamics in COPD. Paper presented at:

American thoracic society ninety-seventh international conference;

May 22, 2001, San Francisco. 3. Martinez FJ. COPD: It emphysema or respiratory disease? Paper presented at: American thoracic society ninety-seventh international conference

, 22 May 2001 San Francisco. .