Validity and Utility of 6-minute-walk Test and WALK(Walking-Stair-Climbing) Test to Assess the Exercise Capacity in Hemodialysis Patients / 대한신장학회잡지

The survival rate in ESRD patients is increased in recent several years. Therefore the Quality of Life and rehabilitation became more important. To evaluate the validity and utility of the walk performance test such as the 6-minute-walk test and WALK test as a substitute of exercise ergometry, we examined the cycle ergometer-graded exercise test for physiologic exercise capacity(VO2max) and walk performance test in hemodialysis patients. The walk performance test was done 3 times of at least 48 hour interval before dialysis in randomly sampled 21 patients. The cycle ergometer-graded exercise test was done in interdialysis day. The result was as following : 1) The mean distance of 6 minute walk test was 472.6+/-105.2m(1st 448.9+/-111.6m, 2nd 479.1+/-89.8m, 3rd 489.9+/-113.4m) and Ratings of Perceived Exertion (RPE) overall 10.4+/-1.7(1st 10.3+/-2.1, 2nd 10.5+/-1.6, 3rd 10.5+/-1.6) and RPE leg 11.2+/-2.7(1st 11.0+/-2.8, 2 nd 11.1+/-2.5, 3rd 11.4+/-2.8). The difference between the test was not significant. 2) The mean time of walking-stair-climbing test was 62.9+/-5.0sec(1st 64.9+/-5.7sec, 2nd 61.9+/-5.7sec, 3rd 61.8+/-5.6sec) and RPE overall 10.7+/-1.9(1st 10.7+/-2.2, 2nd 10.9+/-2.3, 3rd 10.5+/-1.2) and RPE leg 10.9+/-2.7(1st 11.1+/-2.9, 2nd 10.9+/-2.6, 3rd 10.8+/-2.6). The difference between the test was not significant. 3) The VO2max was 13.8+/-5.3mL/kg/min and 46.5+/-14.8% of predicted value. 4) At the finish of the cycle ergometer-graded exercise test, the heart rate did not increase over 100 bpm in 13 patients. 5) The VO2max was significantly correlated with the age(r=-0.604, p<0.01), WALK test(r=-0.453, p<0.05), 6 minute walk test(r=0.561, p<0.05). In conclusion, the 6 minute walk test and WALK test are simple, reliable tests to assess the exercise capacity and predict VO2max in hemodialysis patients.

Validity and Utility of 6-minute-walk Test and WALK(Walking-Stair-Climbing) Test to Assess the Exercise Capacity in Hemodialysis Patients / 대한신장학회잡지

The survival rate in ESRD patients is increased in recent several years. Therefore the Quality of Life and rehabilitation became more important. To evaluate the validity and utility of the walk performance test such as the 6-minute-walk test and WALK test as a substitute of exercise ergometry, we examined the cycle ergometer-graded exercise test for physiologic exercise capacity(VO2max) and walk performance test in hemodialysis patients. The walk performance test was done 3 times of at least 48 hour interval before dialysis in randomly sampled 21 patients. The cycle ergometer-graded exercise test was done in interdialysis day. The result was as following : 1) The mean distance of 6 minute walk test was 472.6+/-105.2m(1st 448.9+/-111.6m, 2nd 479.1+/-89.8m, 3rd 489.9+/-113.4m) and Ratings of Perceived Exertion (RPE) overall 10.4+/-1.7(1st 10.3+/-2.1, 2nd 10.5+/-1.6, 3rd 10.5+/-1.6) and RPE leg 11.2+/-2.7(1st 11.0+/-2.8, 2 nd 11.1+/-2.5, 3rd 11.4+/-2.8). The difference between the test was not significant. 2) The mean time of walking-stair-climbing test was 62.9+/-5.0sec(1st 64.9+/-5.7sec, 2nd 61.9+/-5.7sec, 3rd 61.8+/-5.6sec) and RPE overall 10.7+/-1.9(1st 10.7+/-2.2, 2nd 10.9+/-2.3, 3rd 10.5+/-1.2) and RPE leg 10.9+/-2.7(1st 11.1+/-2.9, 2nd 10.9+/-2.6, 3rd 10.8+/-2.6). The difference between the test was not significant. 3) The VO2max was 13.8+/-5.3mL/kg/min and 46.5+/-14.8% of predicted value. 4) At the finish of the cycle ergometer-graded exercise test, the heart rate did not increase over 100 bpm in 13 patients. 5) The VO2max was significantly correlated with the age(r=-0.604, p<0.01), WALK test(r=-0.453, p<0.05), 6 minute walk test(r=0.561, p<0.05). In conclusion, the 6 minute walk test and WALK test are simple, reliable tests to assess the exercise capacity and predict VO2max in hemodialysis patients.

Juxtaglomerular cell tumor of the kidney: a case report

We report a case of renin-secreting juxtaglomerular cell tumor which developed in a hypertensive 47-yr-old Korean man. Presumptive clinical diagnosis was made before surgery based on the high level of plasma renin and the radiologic evidence of renal mass. Grossly, a round, bulging, well-encapsulated mass of 3x3 cm was located in the mid-portion of the right kidney. On microscopic examination, the tumor was composed of ovoid to polyhedral cells with bland nuclei, indistinct nucleoli and light eosinophilic cytoplasm. The immunostaining for renin showed strong positivity in the cytoplasm of tumor cells. The characteristic rhomboid shaped renin protogranules were observed in ultrastructural analysis.

The influences of maintenance hemodialysis on sleep architecture and sleep apnea in the patients with chronic renal failure / 결핵

BACKGROUND: Sleep-related breathing disorders are commonly found in patients with chronic renal failure and particularly, sleep apnea may have an influence on the long-term mortality rates in these pa tients. Maintenance hemodialysis is the mainstay of medical measures for correcting the metabolic derangements of chronic renal failure but it is uncertain whether it may alleviate sleep disorders including sleep apnea. METHODS: Forty seven patients on maintenance hemodialysis were surveyed with the sleep questionnaire about their clinical symptoms related to sleep disorders. Among them, 15 patients underwent the polysomnography and their blood levels of urea nitrogen, creatinine, electrolytes and the arterial blood gases in the nights before and following hemodialysis were measured. RESULTS: Forty (85.1%) of the 47 patients complained of the symptoms associated with sleep-wake cycle disturbances, 55.3% experienced snoring and 27.7% reported witnessed apneas. The duration of REM sleep increased significantly in the nights after hemodialysis compared to the nights without hemodialysis (p<0.05) and the percentage of total sleep time comprising NREM sleep decreased significantly in the nights following hemodialysis compared to the nights before hemodialysis (p<0.05). The percentage of total sleep time consisting of the stage 1 and 2 NREM sleep showed the trend for a decrease in the nights after hemodialysis (p=0.051), while the percentage of total sleep time comprising the stage 3 and 4 NREM sleep did not change between nights. Tne obstructive sleep apnea was more predominant type than the central one in both nights and there were no differences in the apnea index and the apnea-hypopnea index between the nights. The decrease in the blood level of urae nitrogen, creatinine, potassium and phoshorus was observed after hemodialysis (p<0.05), but the differences of paramenters measured during polysomnography between the nights did not correlate with the changes of biochemical factors obtained on the two night. Arterial blood gas analysis showed that pH was significantly greater in the nights after hemodialysis than in the nights before hemodialysis (p<0.05), but there were no correlations between the parameters examined during polysomnography and the parameters of arterial blood gas anslysis (p<0.05). CONCLUSION: These results suggest that chronic renal failure is an important systemic disorder which is strongly associated with sleep disorders. Maintenance hemodialysis, although it is a widely accepted measure to treat chronic renal failre, did not significantly modulate the sleep architecture and the severity of sleep apnea. Thus, taking the patients with chronic renal failure into account, it is advisable to try not only to find a substantial way for correcting metabolic derangements but also to consider the institution of more effective treatments for sleep disorders.