Although sleep-disordered breathing (SDB) is a major problem in chronic dialysis patients because of its high incidence and poor prognosis, there are no established guidelines for treating SDB. We, therefore, estimated SDB using pulsoximetry the night before hemodialysis and the night after hemodialysis in 85 patients receiving chronic hemodialysis and evaluated the efficacy of oxygen therapy during sleep in 13 patients with SDB.
Forty-two of 85 patients showed a minimal oxygen saturation (SpO₂) below 85%, in 17 patients lower SpO₂ (<90%) persisted for more than 20 minutes and a increased oxygen desaturation index (ODI, ≥15) was observed in 12 patients. There were not significant differences in these three parameters on a comparison of findings before and after hemodialysis. The incidence of SDB was significantly higher in patients with cardiovascular disease. Subsequently, 13 patients received oxygen therapy during sleep and showed improvement of ODI from 16.88±11.58 to 6.49±5.75 (p<0.01), the duration of SpO₂ below 90% decreased from 29.1±29.7min to 11.2±18.2min (p<0.01) and the minimal SpO₂ increased from 72±8% to 80±11% (p<0.01).
Taken together, a high incidence of nocturnal oxygen desaturation due to SDB was observed in chronic dialysis patients, and we propose that oxygen therapy during sleep effectively reduces the frequency of apnea/hypopnea and improves hypoxemia during sleep in these patients.

View full abstract

Recently, it has been reported that cardiovascular calcification is a predictor of mortality in dialysis patients. It has also been reported that the use of calcium salts to correct hyperphosphatemia leads to progression of cardiovascular calcification in dialysis patients. To elucidate the parameters contributing to uremic cardiovascular calcification, in this cross-sectional study, we calculated the aortic calcification index (ACI) using computed tomography (CT) in 101 hemodialysis (HD) patients and examined the presence of cardiac valvular calcification (VC) using an echocardiogram obtained on the same day as CT. We also calculated the subscription dose of calcium carbonate per week (CaCO₃) and the mean values of parameters, which have been reported to affect cardiovascular calcification, such as serum calcium (Ca), and phosphate (P) concentrations, Ca×P product (Ca×P) for 48 weeks before CT was performed. Multiple regression analysis selected age (p<0.01), Ca (p<0.01), and presence of VC (p<0.05) as the significant predictors for the elevated ACI. The presence of VC was associated with longer duration on HD (p<0.05), higher ACI (p<0.01), P (p<0.05), and Ca×P (p<0.05). Multiple regression analysis selected CaCO₃ (p<0.01) as a weak but significant predictor of elevated Ca×P. These results have shown that we need to correct abnormalities in Ca·P metabolism to avoid the progression of uremic cardiovascular calcification and that we should subscribe calcium carbonate as carefully as possible to avoid the elevation of Ca×P.

View full abstract

Clinical significance of cardiac myosin light chain 1 (cMLC1) was investigated in hemodialysis (HD) patients. We performed an echocardiogram and investigated all echocardiographic measurements and analyzed the left ventricular mass index (LVMI) in 127 patients (67 HD patients, 60 non HD patients). Simultaneously, brachial ankle Pulse Wave Velocity (ba PWV) and Ankle Brachial Pressure Index (ABI) was measured using a noninvasive automatic device PWV/ABI (Nihon Colin Co., AT company, Tokyo, Japan), and common carotid artery (CCA) ultrasonography was performed to measure the intima-media thickness (IMT) in the same subjects. Cardiothoracic ratio (CTR) and aortic calcification index (ACI) were also estimated on simple chest X-ray film. The correlations of cMLC1 with the above parameters, laboratory findings including renal function, plasma heart fatty acid-binding protein (H-FABP), cardiac troponin T (cTnT) concentration, and cardiovascular complications were analyzed. For the detection of ischemic heart disease (IHD), multiple regression analysis and receiver operating characteristics (ROC) analysis were performed to estimate the diagnostic efficacy of cMLC1 in HD patients.
The value of cMLC1 was significantly greater in the HD group than in the non HD group (p<0.0001), and was positively correlated with H-FABP/Cr and cTnT in the HD group (r=0.316, p<0.01; r=0.244, p<0.05, respectively). In the HD group, cMLC1 level was significantly greater in the IHD group than in the non IHD group (p<0.05). In the HD group, cMLC1 was negatively correlated with ejection fraction (EF) and percent fractional shortening (%FS) (r=-0.300, p<0.05; r=-0.273, p<0.05, respectively), and was also significantly greater in left ventricular (LV) systolic dysfunction group (EF<50%) than in the normal group (EF≥50%) (p<0.001).
In the HD group, cMLC1 was positively correlated with LVMI, CTR, left ventricular end-systolic dimension (LVDs), left ventricular end-diastolic dimension (LVDd), left ventricular end-systolic volume (LVESV), and left ventricular end-diastolic volume (LVEDV). Multiple regression analysis of IHD demonstrated that cMLC1 was a significantly influential factor. In the HD group, cMLC1 was positively correlated with ba PWV and ACI (r=0.361, p<0.01; r=0.465, p<0.0001, respectively). Multiple regression analysis of ba PWV demonstrated that cMLC1 and systolic blood pressure were significant factors. In the HD group, for the detection of IHD, the area under the ROC curve was 0.692 (p<0.0001) for cMLC1, and sensitivity was 65.0, specificity was 70.4, and the cut-off value was 9.7 (ng/mL). The results of multiple regression and ROC analyses suggest that cMLC1 has a great diagnostic power for the detection of IHD in HD patients.
In conclusion, when the cut-off value was corrected, the value of cMLC1 is a useful and sensitive marker for the detection of IHD and for the evaluation of LV dysfunction and LV hypertrophy even in HD patients.

View full abstract

The number of patients undergoing dialysis has been increasing annually in Japan, exceeding 230, 000 in 2003. While the numbers of dialysis patients continue to increase, the number of patients receiving kidney transplants are still small. One reason for this is that the number of patients desiring a kidney remains low. In Yamanashi prefecture both the numbers of kidney transplants and patients on the waiting list for kidney transplants have only slightly increased. A survey was therefore planned in dialysis patients to clarify their opinion about kidney transplantation. Among 723 patients who responded, 352 patients had considered kidney transplantation, 171 patients desired a kidney transplant, but only 70 patients (<10% of the total) were registered on the Japan Organ Transplant Network. Reasons for not registering included: no desire for a transplant (32.5%); agerelated issues (28.2%); lack of information about the network (13.4%); and a feeling that it was pointless (11.1%). Since no less than 171 patients expressed a desire for kidney transplant and 93 patients had not been informed the Japan Organ Transplant Network, vigorous campaign of kidney transplantation being required.

View full abstract

A 74 year-old male hemodialysis (HD) patient with a HD duration of 1 year underwent a resection of the ulnar nerve neurinoma on June, 2003. One week after the surgery, 2 hours after the cessation of a routine 4-hour HD without any complications, he suddenly complained epigastralgia referred across the upper abdominal wall. Then, numbness and muscle weakness of both lower legs developed, and finally paralytic paraplegia was completed within several hours. On the next morning, paraplegia had still persisted, and the dissociated anesthesia below the level of Th8, rectal obstruction, and areflexia were newly observed. Most possible cause for his symptoms and signs was considered to be vascular accident of the spinal cord, we performed MR imaging on the same day. MR imaging revealed spinal swelling lesions on T1-weighted image which was high-intensity lesion on T2-weighted image at the level between Th8 and Th12, indicating spinal cord infarction. The administration of both argatroban (60mg/day day 1-2) and glycerin (200mL×2/day day 1-7) in conjunction with hyperbaric oxygenation was started. Rehabilitation was started 7 days after the onset, although the improvement of his symptoms was not evident. He was repeatedly complicated with pneumonia due to the difficulty in expectoration.
There are a few case reports in which spinal cord infarction was diagnosed by MR imaging in HD patients. The present case showed the typical course and MR images of the disease. The severe systemic arteriosclerosis was considered to be a causative etiology for the onset.

View full abstract

A 70-year-old male patient who had been on hemodialysis due to idiopathic kidney disease was transferred to continuous ambulatory peritoneal dialysis (CAPD) because of hypotension during hemodialysis sessions.
Immediately following the start of CAPD, he developed ultra-filtration failure (UFF). Peritoneal equilibration test demonstrated a high transport peritoneum (D/P Cr=0.81). Measurement of lymphatic absorption using ^99mTc-HSAD showed a lymphatic absorption of 343mL/4h. After administration of tranexamic acid, UFF was dramatically reduced and lymphatic absorption decreased markedly. However, there was no change in the high transport peritoneum (D/P Cr=0.89). We conclude that tranexamic acid administration improves UFF in CAPD patients through inhibition of lymphatic absorption.

View full abstract