Risk factors for hypotension in patients with hemodialysis-associated superior vena cava syndrome.

OBJECTIVE: We analyzed the risk factors for hypotension in patients with hemodialysis-associated superior vena cava syndrome (SVCS) and effectiveness of endovascular intervention in hypotension related to SVCS. METHODS: This was a retrospective cohort study. A total of 194 maintenance hemodialysis patients diagnosed with SVCS who were admitted to the Department of Nephrology, West China Hospital of Sichuan University from January 2019 to December 2021 were selected and divided into a hypotension group and a nonhypotension group. Demographic and clinical data were compared. Hypotension simply refers to blood pressure levels of <90/60 mm Hg on a nondialysis day. All patients received endovascular intervention. RESULTS: Hypotension was found in 85 of the 194 patients. The following factors were significantly different between the hypotension and nonhypotension groups: body mass index, history of hypertension, tunneled-cuffed catheter as the means of dialysis access, azygos ectasis, SVC stenosis of >70% or occlusion, occlusion at the cavitary junction, serum calcium, diastolic left ventricular (LV) posterior wall thickness, LV end-diastolic volume, stroke output, and LV ejection fraction. Multivariate logistic regression analysis showed that hypertension history (OR, 0.314; P = .027), tunneled-cuffed catheter as vascular access (OR, 3.997; P < .001), SVC stenosis of >70% or occlusion (OR, 5.243; P < .001), LV posterior wall thickness (OR, 0.772; P = .044), and serum calcium (OR, 0.146; P = .005) were independent risk factors for hypotension. The mean values of systolic and diastolic blood pressure after intravascular treatment were significantly elevated from those before intervention (P < .001). The primary patency rates of SVC were 66.8%, 58.7%, and 50.0% at 3, 6, and 12 months after the procedure. CONCLUSIONS: The incidence of hypotension in patients with hemodialysis-associated SVCS is high. The identification of risk factors of hemodialysis-related hypotension provides insight into potential treatment strategies. Endovascular treatment is expected to improve hypotension related to SVCS in hemodialysis patients.

Percutaneous endovascular arteriovenous fistula: A systematic review and meta-analysis.

Objective: Currently, percutaneous endovascular creation of arteriovenous fistula (AVF) shows excellent outcomes. However, few systematic research evidence to support clinical decision making on the benefit of endovascular AVF is available. The purpose of this study was to evaluate the efficacy and safety of endovascular AVF (endoAVF) in patients with renal failure. Methods: We searched the Medline, Embase, Cochrane Library, and ClinicalTrials.gov databases for studies on endovascular or endovascular versus surgery for the creation of AVF. Two reviewers independently selected studies and extracted data. A systematic review and meta-analysis were performed by Review Manager 5.4 software (Revman, The Cochrane Collaboration, Oxford, United Kingdom) and Stata 15.0 (Stata Corp, College Station, TX, United States). Results: A total of 14 case series and 5 cohort studies, with 1,929 patients, were included in this study. The technique success was 98.00% for endoAVF (95% CI, 0.97-0.99; I 2 = 16.25%). There was no statistically significant difference in 3 cohort studies between endovascular and surgical AVF for procedural success (OR = 0.69; 95% CI, 0.04-11.98; P = 0.80; I 2 = 53%). The maturation rates of endoAVF were 87.00% (95% CI, 0.79-0.93; I 2 = 83.96%), and no significant difference was observed in 3 cohort studies between the 2 groups (OR = 0.73; 95% CI, 0.20-2.63; P = 0.63; I 2 = 88%). Procedure-related complications for endoAVF was 7% (95% CI, 0.04-0.17; I 2 = 78.31%), and it did not show significant difference in 4 cohort studies between the 2 groups (OR = 1.85; 95% CI, 0.37-9.16; P = 0.45; I 2 = 59%). Conclusion: The endovascular creation of AVF is potentially effective and safe. These important data may provide evidence to support clinicians and patients in making decisions with endovascular AVF. But further research is great necessary due to lack of randomized controlled studies.

The efficacy and safety of blunt impingement followed by a sharp recanalization technique in hemodialysis patients with refractory central vein occlusion: a single-center experience.

Background: Central vein occlusion (CVO) is a serious problem in hemodialysis patients. There is an unsatisfactory result for refractory CVO by sharp recanalization alone. This study evaluated the efficacy and safety of blunt impingement followed by sharp recanalization for the treatment of CVO in hemodialysis patients. Methods: This study retrospectively examined hemodialysis patients with CVO who failed to recanalize using standard guidewire and catheter techniques in our department. In the first instance, all CVOs were recanalized using blunt impingement techniques, including a 6-Fr long sheath (Cook Incorporated, Bloomington, IN USA) and an 8-Fr sheath of Rosch-Uchida Transjugular Liver Access Set (RUPS-100; Cook Incorporated, Bloomington, IN, USA). If this was not successful, sharp recanalization devices were applied, including the stiff tip of a guidewire (Terumo, Tokyo, Japan), the RUPS-100, and the percutaneous transhepatic cholangial drainage (PTCD) needle (Cook Incorporated, USA). All patients were followed up at least 4 months postoperatively. The technical success rate, arteriovenous access patency rates, and operation-related complications were analyzed. Results: The procedural success rate was 100.0% (30 of 30). Thirty patients with CVO underwent blunt impingement with a technique success rate of 70.0% (21 of 30), and 9 patients received sharp recanalization after failed blunt impingement, with a technique success rate of 100.0% (9 of 9). The primary patency rates at 6 and 12 months postoperatively were 86.7% and 53.3%, respectively. The primary assisted patency rates were 93.3% and 63.3%, and the secondary patency rates were 93.3% and 70.0% at 6 and 12 months, respectively. One major procedure-related complication was detected, namely, a small injury of the superior vena cava (SVC) wall in a patient receiving recanalization via the stiff end of a guidewire, but this did not require further treatment. Conclusions: It is potentially effective and safe for interventionalists to use blunt impingement followed by sharp recanalization techniques to treat chronic CVO that is refractory to traversal using traditional catheter and guidewire techniques.

Percutaneous superior vena cava puncture successful recanalization of a long-segment, angled central venous occlusion: a case report.

BACKGROUND: Multiple complete central venous occlusion (CVO) is rare complication among the hemodialysis population. Percutaneous transluminal angioplasty (PTA) is the recommended treatment for CVO; however, cases with long-segment occlusion remain challenging. CASE DESCRIPTION: We reported a patient who complained of a swollen right arm for 1 month. On admission, his vital signs were within normal limits. The 76-year-old man had been on hemodialysis with a right forearm arteriovenous fistula (AVF) for 4 years with a history of temporizing catheterization and left forearm AVF failure. One year ago, he gradually developed a slight swelling in his right arm and the swelling in his arm was significantly worse one month ago. Digital subtraction angiography (DSA) revealed occlusion in his right innominate vein (IV), proximal subclavian vein (SV), and external and internal jugular veins, as well as stenosis of the ipsilateral cephalic arch and axillary vein (AV). The operation was performed with a pioneered bidirectional approach via ipsilateral superior vena cava (SVC) and AV puncture. The occluded lesions were successfully recanalized, and the patient's symptoms resolved after the operation. The patency of his vascular access was well maintained at the 4-month follow-up. CONCLUSIONS: To the best of our knowledge, this is the first report regarding the application of SVC puncture in PTA for CVO. This technique could be a possible approach when performed by appropriately qualified operators in patients with limited or no other options.

Sharp recanalization for long-segment superior vena cava occlusion in a hemodialysis patient with vascular resource exhaustion: a case report.

Hemodialysis is the lifeline of end-stage renal patients, and the correct choice of vascular access is vital to patients with vascular resource exhaustion. A 57-year-old female was admitted to the hospital due to catheter dysfunction. Color-doppler ultrasound (CDU) showed that the patient's inferior vena cava (IVC), right brachiocephalic vein, and long segment of the superior vena cava (SVC) were occluded. During surgery, we found that the obstruction of the SVC extended from the opening of the azygous vein to the junction of the SVC and the right atrium and was 6.9 cm in length. Under fluoroscopic guidance, the original tunneled cuffed catheter (TCC) was pulled out, a 4-French sheath was implanted into the right, and a guidewire was inserted to locate the distal end of the SVC. Another puncture needle was inserted from the right brachiocephalic vein into the distal end of the SVC and the steel core of the Rosch-Uchida Transjugular Liver Access Set (RUPS-100) was then inserted through the puncture needle. After correcting the positive and lateral position and determining the way in which the SVC entered the right atrium from the distal end, a 0.035-inch hard guidewire was then inserted into the right atrium through the steel core and a 6-mm balloon was used to dilate the SVC. The end of the catheter was then implanted into the IVC. No surgical complications occurred and at the 30-month follow-up and time of writing, the catheter remained primarily patent. The use of the RUPS-100 for sharp recanalization of an occluded long segment of the SVC can increase the likelihood of patient survival, but the risks during this operation are still not negligible and require precise guidance.

Account for Clinical Heterogeneity in Assessment of Catheter-based Renal Denervation among Resistant Hypertension Patients: Subgroup Meta-analysis.

BACKGROUND: Catheter-based renal denervation (RDN) is a novel treatment for resistant hypertension (RH). A recent meta-analysis reported that RDN did not significantly reduce blood pressure (BP) based on the pooled effects with mild to severe heterogeneity. The aim of the present study was to identify and reduce clinical sources of heterogeneity and reassess the safety and efficacy of RDN within the identified homogeneous subpopulations. METHODS: This was a meta-analysis of 9 randomized clinical trials (RCTs) among patients with RH up to June 2016. Sensitivity analyses and subgroup analyses were extensively conducted by baseline systolic blood pressure (SBP) level, antihypertensive medication change rates, and coronary heart disease (CHD). RESULTS: In all patients with RH, no statistical differences were found in mortality, severe cardiovascular events rate, and changes in 24-h SBP and office SBP at 6 and 12 months. However, subgroup analyses showed significant differences between the RDN and control groups. In the subpopulations with baseline 24-h SBP ≥155 mmHg (1 mmHg = 0.133 kPa) and the infrequently changed medication, the use of RDN resulted in a significant reduction in 24-h SBP level at 6 months (P = 0.100 and P= 0.009, respectively). Subgrouping RCTs with a higher prevalent CHD in control showed that the control treatment was significantly better than RDN in office SBP reduction at 6 months (P < 0.001). CONCLUSIONS: In all patients with RH, the catheter-based RDN is not more effective in lowering ambulatory or office BP than an optimized antihypertensive drug treatment at 6 and 12 months. However, among RH patients with higher baseline SBP, RDN might be more effective in reducing SBP.

An establishment of vascular access through superior vena cava for a patient with multiple central venous stenosis or occlusion.

The patency of vascular access is of vital importance to dialysis patients. Access dysfunction is largely caused by vessel stenosis and thrombosis. Nephrologists usually find themselves helpless when all treatments fail and the vascular access seems to have exhausted. Here we report a successful establishment of vascular access through superior vena cava for a critical patient with multiple central venous stenosis or occlusion. To our knowledge, it is the first case ever reported on the successful establishment of vascular access through superior vena cava under such a complicated condition of vascular exhaustion.

Resolvin D1 Protects Lipopolysaccharide-induced Acute Kidney Injury by Down-regulating Nuclear Factor-kappa B Signal and Inhibiting Apoptosis.

BACKGROUND: Resolvin D1 (RvD1) is a newly found anti-inflammatory bioactive compound derived from polyunsaturated fatty acids. The current study aimed to explore the protective effect of RvD1 on lipopolysaccharide (LPS)-induced acute kidney injury (AKI) and its possible mechanism. METHODS: Both in vivo and in vitro studies were conducted. Male BALB/c mice were randomly divided into control group (saline), LPS group (LPS 5 mg/kg), RvD1 group (RvD1 5 µg/kg + LPS 5 mg/kg), and blockage group (Boc-MLP 5 µg/kg + RvD1 5 µg/kg + LPS 5 mg/kg). Boc-MLP is a RvD1 receptor blocker. The mice were intraperitoneally injected with these drugs and recorded for general condition for 48 h, while the blood and kidneys were harvested at 2, 6, 12, 24, and 48 h time points, respectively (n = 6 in each group at each time point). Human proximal tubule epithelial cells (HK-2) were randomly divided into control group (medium only), LPS group (LPS 5 µg/ml), RvD1 group (RvD1 10 ng/ml + LPS 5 µg/ml), and blockage group (Boc-MLP 10 ng/ml + RvD1 10 ng/ml + LPS 5 µg/ml). The cells were harvested for RNA at 2, 4, 6, 12, and 24 h time points, respectively (n = 6 in each group at each time point). Blood creatinine was tested by using an Abbott i-STAT portable blood gas analyzer. Tumor necrosis factor-α (TNF-α) level was detected by ELISA. Kidney pathology was observed under hematoxylin and eosin (HE) staining and transmission electron microscope (TEM). We hired immune-histological staining, Western blotting, and fluorescence quantitative polymerase chain reaction to detect the expression of RvD1 receptor ALX, nuclear factor-kappa B (NF-κB) signaling pathway as well as caspase-3. Kidney apoptosis was evaluated by TUNEL staining. RESULTS: RvD1 receptor ALX was detected on renal tubular epithelials. Kaplan-Meier analysis indicated that RvD1 improved 48 h animal survival (80%) compared with LPS group (40%) and RvD1 blockage group (60%), while RvD1 also ameliorated kidney pathological injury in HE staining and TEM scan. After LPS stimulation, the mRNA expression of toll-like receptor 4, myeloid differentiation factor 88, and TNF-α in both mice kidneys and HK-2 cells were all up-regulated, while RvD1 substantially inhibited the up-regulation of these genes. Western blotting showed that the phosphorylated-IκB/IκB ratio in LPS group was significantly higher than that in the control group, which was inhibited in the RvD1 group. RvD1 could inhibit the up-regulation of cleaved-caspase-3 protein stimulated by LPS, which was prohibited in RvD1 blockage group. RvD1 group also had a lower proportion of apoptotic nuclei in mice kidney by TUNEL staining compared with LPS group. CONCLUSION: In LPS-induced AKI, RvD1 could decrease TNF-α level, ameliorate kidney pathological injury, protect kidney function, and improve animal survival by down-regulating NF-κB inflammatory signal as well as inhibiting renal cell apoptosis.

[Mellitin induced acute kidney injury and continuous renal replacement therapy in goat model].

OBJECTIVE: To establish a goat model of melittin induced acute kidney injury (AKI), and to evaluate the therapeutic effect of continuous veno-venus heamofiltration (CVVH) in melittin- induced AKI. METHODS: Twelve male goats were randomized into three groups: control group, melittin induced AKI group (melittin group), and CVVH intervention group (CVVH group). The AKI goat model was established by the injection of melittin via the auricular vein for four times in 48 h to reach a total dose of 0.5 mg/kg, then serum creatinine (Cr) and creatine kinase (CK) were tested every 6 h and urine output was record each hour. AKI was diagnosed when Cr level increased to the double value of control group, or the urine output decreased to less than 0. 5 mL/(kg x h) in 6 h. After the diagnosis of AKI, the animals in CVVH group received CVVH treatment for 12 h. At the end, the goats in all groups were sacrificed by anesthesia and kidney tissue samples were collected. Light microscopy and telectron microscopy observation were performed. Apoptosis was detected by immunohistochemistry and TUNEL technique. RESULTS: AKI was successfully induced by melittin in the goats. The Cr level in control group was (43.95 +/- 1.59) micromol/L, while (100.75 +/- 7.87) micromol/L in AKI group and (102.10 +/- 5.06) micromol/L in CVVH group. Cr level was lowered significantly after CVVH treatment [(45.02 +/- 2.41) micromol/L in control group vs. (108.60 +/- 9.40) micromol/L in AKI group vs. (64.13 +/- 5.82) micromol/L in CVVH group, P < 0.001]. Swelling and reduction of mitochondrial crests in AKI group were more obvious than those in CVVH group. Expression of caspase-3 and apoptosis cells percentage of renal tubules in AKI group were significantly higher than those in CVVH group. CONCLUSION: Melittin induced AKI model could be established in goats. CVVH could alleviate melittin induced AKI, probably in the mechanism to reduce the apoptosis of renal tubular cells.

Influence of HbA1c on short-term blood pressure variability in type 2 diabetic patients with diabetic nephropathy.

The aim of this study was to understand the characteristics of blood pressure (BP) variability in subjects with diabetic nephropathy (DN), and identify the probable predictors affecting BP variability. Fifty-one chronic kidney disease (CKD)-hypertensive patients without diabetes (NDN group) and sixty type 2 diabetic patients with overt DN (DN group) were enrolled in this study. The values of short-term BP variability were obtained from 24 h ambulatory BP monitoring (ABPM). Variance analysis or nonparametric analysis revealed that 24-h systolic BP variability and nighttime systolic BP variability of the DN group were significantly higher than those of the NDN group [(12.23±3.66) vs. (10.74±3.83) mmHg, P<0.05; (11.23±4.82) vs. (9.48±3.69) mmHg, P<0.05]. Then the patients of the DN group were divided into two groups according to glycated hemoglobin (HbA1c) level: Group A (HbA1c<7%) and Group B (HbA1c≥7%), and the t-test showed that patients in Group B had larger 24-h diastolic, daytime diastolic, and nighttime systolic/diastolic BP variability compared with Group A. In the DN group, partial correlation analysis revealed that HbA1c exhibited a strong association with 24-h diastolic, daytime diastolic, nighttime systolic and diastolic BP variability (P<0.001, P<0.001, P<0.05, and P<0.001, respectively). Taken together, larger short-term BP variability was detected in hypertensive type 2 diabetic patients with overt nephropathy and renal insufficiency. It may imply that the optimal BP variability level could benefit from a better glycaemic control.

[Association of diabetes and early failure of arteriovenous fistula in the end stage of renal diseases].

OBJECTIVE: To determine the association of diabetes and glycemic control with early failure of native arteriovenous fistula(AVF). METHODS: 266 patients with end stage renal diseases(ESRD) were recruited and divided into non-diabetic group (165), HbA1C < 7% group (51) and HbA1C > or = 7% group (50). Clinical indicators and early failure of AVF were examined. RESULTS: In total, 63 (23.7%) patients had AVF early failure. The AVF early failure occurred in 18. 1% of patients in the non-diabetic group and 21.6% of patients in the HbA1C < 7% group, significantly less than that in the HbA1C > or = 7% group (44%). The COX regression model showed that increased HbA1C, total cholesterol (TC) and decreased high-density lipoprotein (HDL)increased the risk of AVF failure. CONCLUSION: The levels of glycemic and serum lipid subfractions are associated with AVF early failure in ESRD patients. Good control of glycemic and lipid can lower the rates of AVF early failure.

Application of hybrid blood purification treatment for severe acute arsine poisoning.

OBJECTIVE: Severe acute arsine poisoning (SAAP) complicated by multiple organ dysfunction syndrome is a critical clinical illness. The limited efficacy of conventional drug therapy prompted us to investigate the application of hybrid blood purification treatment (HBPT) to improve the prognosis in critically ill patients. The present manuscript describes a series of cases treated with HBPT. METHODS: Eleven SAAP subjects were enrolled. The study did not include a control group, because of ethical issues. On the basis of conventional therapy, HBPT (plasma exchange [PE] + continuous venovenous hemofiltration [CVVH]) was used to treat SAAP. PE was performed once a day for 5 days, and CVVH was performed after each session of PE for 7 days or more; HBPT treatment duration amounted to an average of 10 days (range 7-18 days). Arsenic was detected in blood and discarded liquid. Clinical indicators, laboratory parameters, and prognostic indicators were assessed. RESULTS: HBPT was smoothly implemented without obvious adverse reaction. It can continuously remove arsenic and terminate hemolysis in a time-dependent manner. HBPT also significantly improved the poor clinical manifestations and laboratory indicators of SAAP, leading to a low mortality. Ten patients were discharged because of improved conditions, and only 1 patient died. CONCLUSIONS: The early application of HBPT can improve the prognosis of SAAP. The advantage of HBPT is that it can integrate the characteristics of different blood purification technologies to maximize treatment efficacy.

Combined blood purification for treating acute fatty liver of pregnancy complicated by acute kidney injury: a case series.

Acute fatty liver of pregnancy (AFLP) complicated by acute kidney injury (AKI) is serious and life-threatening for the mother. The present study aimed to determine the clinical efficacy of combined blood purification treatment (CBPT) in patients with AFLP complicated by AKI. The CBPT involves plasma exchange (PE) combined with continuous venovenous hemofiltration (CVVH). The subjects were 17 patients with AFLP complicated by AKI. The CBPT was implemented based on the timely termination of pregnancy and general treatment. Changes in clinical manifestations, laboratory tests, liver ultrasounds, as well as Sequential Organ Failure Assessment (SOFA) and Glasgow scores were evaluated. The efficacy and adverse reactions of the CBPT were also assessed. The CBPT was smoothly performed without any obvious adverse reaction. After treatment, the clinical manifestations, laboratory examinations, and liver ultrasonography significantly improved. Therefore, the SOFA scores correspondingly decreased 1 week after treatment [9 (range 5-11) vs. 3 (range 0-10), P = 0.002], and the median was close to normal by the second week. The clearance rate of the total bilirubin in PE was significantly higher than that in CVVH (37.2 vs. 7.9%, P = 0.000). The incidence of acute pulmonary edema in CVVH was less than that in PE (0 vs. 41.2%, P = 0.007). Finally, the maternal mortality was 5.88% (95% CI: 0-29%). Overall, we think that CBPT aids in the recovery of liver and kidney function. Different blood purification methods may be combined to integrate and maximize their advantages to improve the prognoses of patients with serious AFLP.