Biomedical subjects

F Woltering

Publications and source records attributed to F Woltering.

3 recordsLinked to original sources

PubMed1999

Randomized reliability study evaluating constant-load and graded-exercise treadmill test for intermittent claudication.

The aim of this randomized study was to compare the reliability of the treadmill test at constant-load (C-test, 3 km/hr; fixed grade of 12%) recommended in Germany with that of the graded-exercise test (G-test, 3 km/hr; increase in grade of 3.5% every 3 minutes) propagated in the United States. In 50 patients with an absolute claudication distance (ACD) in the C-test of between 50 and 400 m, the two treadmill tests were carried out in randomized order on one and the same day, and repeated on 3 days within 1 week. For the initial claudication distance (ICD), the intraclass correlation was 0.88 in the C-test and 0.87 in the G-test. For the ACD the coefficients were identical at 0.91. The within-subject variation (CVwithin) in the C-test and G-test was 25% and 27% for the ICD and for the ACD 24% and 21%, respectively. The between-subject variation was very similar with 72% and 73% (ICD) and with 78% and 68% (ACD). However, in ACDs below 100 m and between 100 to 150 m, the C-test showed significantly smaller coefficients of variation than the G-test: 13% vs 81% and 14% vs 50%, respectively. In conclusion, the results showed that both C-test and G-test are equally well reproducible.

Analysis of Variance↗

PubMed1997

Treadmill testing for evaluation of claudication: comparison of constant-load and graded-exercise tests.

OBJECTIVES: To compare the correlation and practicability of single-stage vs. graded treadmill protocols in the assessment of the absolute claudication distance (ACD). DESIGN: Randomized open study. MATERIAL AND METHODS: In 52 patients with peripheral arterial occlusive disease, the ACD on treadmill at 3 km/h and 12% grade (constant-load test = C-test) ranged form 50 to 400 m. The C-test and the graded-exercise test (walking on the treadmill at 3 km/h and 0% gradient for 3 min, with subsequent increase in gradient of 3.5% every 3 min = G-test) were carried out at random on the same day under standardized conditions. RESULTS: The ACD was higher in the G-test than in the C-test (360.4 +/- 208.8m vs. 166.5 +/- 93.6m; p < 0.001). The coefficients of variation were very similar (57.9% and 56.2%, respectively). In the subgroup of patients with an ACD of between 100 m and 150 m, a large difference was found both for the coefficient of variation (58.6% G-test, 9.6% C-test) and for the standard deviation (339.8 +/- 199.0m and 133.1 +/- 12.8m, respectively). CONCLUSIONS: For the assessment of the ACD in patients with severe claudication the C-test would seem to be more suitable than the G-test.

Exercise Test↗

PubMedDate not supplied

Prevention of contrast media-induced renal dysfunction with prostaglandin E1: a randomized, double-blind, placebo-controlled study.

Preexisting renal impairment is an all-encompassing risk factor for radiocontrast-associated nephrotoxicity. Renal impairment appears to be associated with the inadequate production of renal prostaglandins at the critical time of radiocontrast administration and for a variable time period afterward. We prospectively studied 130 patients with chronic renal insufficiency (serum creatinine > or =1.5 mg/dL) who were undergoing radiocontrast administration. Using a double-blind, randomized, prospective technique, patients were assigned to either placebo or one of three prostaglandin E1 (PGE1) treatment groups (10, 20, or 40 ng/kg/min). Infusion was started 60 +/- 30 minutes before the administration of radiocontrast and was continued for a total of 6 hours. In the placebo group, radiocontrast administration resulted in a mean increase (+/- SD) in serum creatinine of 0.72 +/- 1.15 mg/dL at 48 hours. This increase was less in each of the PGE1 treatment groups after 48 hours, with a significant difference between placebo and the 20 ng/kg/min PGE1 group (P = 0.01). Using baseline adjusted means, analysis of covariance with baseline serum creatinine as the covariable demonstrated significant differences between the placebo and 20 ng/kg/min PGE1 group (P = 0.03) and between the placebo and 10 ng/kg/min PGE1 group P = 0.047). In a subgroup analysis of the diabetic patients, the increase in serum creatinine was less pronounced in the three PGE1 groups versus the placebo group, and the 20 ng/kg/min PGE1 group had the most favorable outcome. The parenteral administration of PGE1 immediately before radiocontrast exposure and continued for a period of 5 to 5.5 hours significantly reduced the elevation of serum creatinine poststudy. The most effective of the three PGE1 dosing regimens was 20 ng/kg/min.

Aged↗