Images (68)
Showing first 60 of 68 pages.
दस्तावेज़
| id |
id
621041624
|
|---|---|
| contentType |
contentType
document
|
| source |
source
import
|
Source image fields (6)
Extracted text
OCR Page 1 of 6821
these improvements seem to be maintained, but very few of the patients were available for
assessment of FVC at that time period.
A third pulmonary function test used to evaluate the affects of LVRS is residual volume (RV).
RV, which is also measured in liters, records the amount of air left in the lung after the patient has
fully expired a breath. This test is unique because it is inversely proportional to the other
pulmonary function measurements. A decrease in RV means that the patients' pulmonary
function has improved, whereas FEV1 and FVC increase in value when improvement has
occurred. Fewer of these studies reported RV relative to the other end points, particularly at
multiple time periods. The data available suggest 3 month improvements of 25% - 30%. In
contrast to the other measures, the limited data implies reversal of these improvements between 6
and 12 months post-surgery.
A fourth end point used was the six minute walk test (6MWT). The 6MWT measures the
distance a patient can walk in six minutes and improves with rehabilitation. This measure of
exercise capacity was used in 10 of the 18 studies. Three month increases in 6MWT --a measure -
-
for which baseline values varied considerably ranged from 13% - 60%. Again, very limited
data suggest a maintenance or further improvement in this outcomes at later time periods. It is
not clear how much of the improvement in 6MWT is due to rehabilitation, not just surgery.
Other end points were also used in an attempt to quantify improvements in patients who
underwent LVRS. Various QOL measures and dyspnea scales were used in these studies.
Although these tools can provide valuable patient information, it is difficult to assess these
findings in the aggregate because the studies used different scales to measure outcomes. In terms
of dyspnea scales, 10 of the 18 clinical studies reviewed for this report used at least one
mechanism to record the level of breathing difficulty in the patients studied. Six of the 10 used a
single dyspnea scale; two studies used the Mahler Dyspnea Scale (MDS), while the other four
studies independently used the Borg Scale, Fletcher's Dyspnea Scale, the Transitional Dyspnea
Index (TDI) or the Medical Research Council Dyspnea Scale (MRC). Four studies used two
scales in reporting results. Two of these used the MDS and the MRC while the other used the
TDI and the MRC and the Borg and the MRC, respectively.
In the 1960's, Borg developed a category scale for ratings of perceived exertion. Borg modified
this scale in 1970 in order to increase linearly with the exercise intensity for work on a cycle
ergometer. Further modifications were made in 1980 and studies were published revealing the
new rating scale constructed as a category scale with ratio properties. The Borg scale, in
combination with other mechanisms to measure dyspnea, was used in three of the studies
reviewed.
Another measurement of breathlessness used is the Mahler dyspnea scale. This mechanism uses a
questionnaire that is administered by an interviewer who has been provided with basic instruction.
Three domains of dyspnea are evaluated: magnitude of task, magnitude of effort and functional
impairment. At the time of the baseline evaluation, the domains are each scored in integers from 0
Relations
belongs_to