Toshiro Katayama

Emphysematous lungs do not affect visibility of virtual-assisted lung mapping.

Background It has recently been suggested that virtual-assisted lung mapping may enable safer and more reliable intraoperative navigation compared to conventional preoperative lung marking strategies. This study aimed to examine the relationship between emphysematous lungs and the intraoperative visibility of virtual-assisted lung mapping markings. Methods We retrospectively analyzed the data of 21 patients who underwent virtual-assisted lung mapping followed by lung resection between October 2013 and May 2015. The visibility of the intraoperative lung markings was graded. The degree of pulmonary emphysema was assessed by the percentage of low attenuation area on computed tomography. We elucidated the associations between the marking grade and other factors such as patient age or sex, pulmonary lobe mapped, marking operator, Brinkman index, and percentage of low attenuation area of the pulmonary lobe. Results In Spearman rank correlation analysis, there was no correlation between the Brinkman index and the percentage of low attenuation area (n = 26, r = −0.016, p = 0.937). In stepwise multivariate regression analysis, the marking grade correlated with the marking operator (p < 0.001) and the Brinkman index (p = 0.008), but not with patient age or sex, the pulmonary lobe mapped, or degree of pulmonary emphysema. Conclusion The skill of the marking operator and the patient’s smoking history had significant effects on the intraoperative visibility of markings made by virtual-assisted lung mapping, whereas emphysematous lungs did not affect the intraoperative visibility of lung markings.

Assessment of a change of blood volume during hemodialysis

Hemodialysis influences intradialytic hypotension, decreasing the blood volume (BV) in circulation. If intradialytic hypotension has continued, the patient may occur an unconscious. In this study, we focused on the changes of the BV in circulation to prevent them from intradialytic hypotension and unconscious. Based of hematocrit value correlate with the reflected light intensity from blood, we estimated BV. We constructed the mathematical model to explain the water movement from the extracellular to the intravascular compartment during hemodialysis. As a result, the changing pattern of BV differed on each patient, a coefficient of the water movement were estimated in this study. The coefficient of the water movement was invariable in the individual case and differed among patients. We could expect the individual change of BV by using the coefficient.

The features in IgA-dominant infection-related glomerulonephritis distinct from IgA nephropathy: a single-center study

BackgroundIgA-dominant infection-related glomerulonephritis (IgA-IRGN) is a unique form of IRGN, which needs to be distinguished from IgA nephropathy (IgAN).MethodsThirteen patients with IgA-IRGN (IgA-IRGN group) and 122 with IgAN (IgAN group) were selected from 1788 patients who underwent kidney biopsy between 2000 and 2015 in Kitano Hospital. Data selected included clinical and serological parameters; light and electron microscope findings; immunofluorescence findings; and prognostic parameters like renal and overall survival and creatinine increase by > 50%. In addition, a 26-patient IgAN cohort (matching-IgAN), matching with IgA-IRGN group with respect to age, sex, estimated glomerular filtration rate (eGFR), and proteinuria was segregated for comparison.ResultsCompared to IgAN group, IgA-IRGN group were older, had lower hemoglobin, higher CRP, lower eGFR, heavier proteinuria, lower serum albumin, and higher serum IgG and IgA levels (p < 0.05). Endocapillary hypercellularity, deposition of immune complexes along the glomerular capillary wall, and subendothelial and subepithelial electron dense deposits were more frequently observed (p < 0.05); and they were more susceptible to renal dysfunction and poorer prognosis. After propensity score-matching, serum albumin was significantly lower in the IgA-IRGN group. Significantly subendothelial and subepithelial deposits were frequently observed in this group. Matching-IgAN group showed relatively advanced sclerotic lesions with more global sclerosis and fibrous crescent.ConclusionLocal inflammation involved glomerular capillary wall in IgA-IRGN, in contrast to relatively chronic and sclerotic renal lesion in IgAN, might result in poorer prognosis in former, even under indistinguishable condition of deteriorated renal function and proteinuria.

Long acting β 2 -adrenocepter agonists are not associated with atrial arrhythmias after pulmonary resection

BackgroundLong-acting β2-adrenoceptor agonists have been shown to increase the risk of atrial arrhythmias in patients with stable chronic obstructive pulmonary disease. The aim of this study was to investigate whether perioperative long-acting β2-adrenoceptor agonists treatment would increase the risk of postoperative atrial arrhythmias after lung cancer surgery in chronic obstructive pulmonary disease patients.MethodsWe retrospectively analyzed 174 consecutive chronic obstructive pulmonary disease patients with non-small-cell lung cancer who underwent lobectomy or segmentectomy. The subjects were divided into those with or without perioperative long-acting β2-adrenoceptor agonists treatment. Postoperative cardiopulmonary complications were compared between the two groups.ResultsThere were no statistically significant differences between the perioperative long-acting β2-adrenoceptor agonists treatment group and the control group in the incidence of postoperative atrial arrhythmias (P = 0.629). In 134 propensity-score–matched pairs, including variables such as age, gender, comorbidities, smoking history, operation procedure, lung-cancer staging, and respiratory function, there were no significant differences between the two groups in the incidence of postoperative cardiopulmonary complications, including atrial arrhythmias.ConclusionsPerioperative administration of long-acting β2-adrenoceptor agonists might not increase the incidence of postoperative atrial arrhythmias after surgical resection for non-small-cell lung cancer in chronic obstructive pulmonary disease patients.

A study on the fluctuation of HCV antigens during hemodialysis therapy of dialysis patients with the HCV infection using Langmuir's adsorption isotherm

The levels of hepatitis C virus (HCV) are reported to be lower in dialysis patients than those in HCV-positive non-dialysis patients. In order to explain this clinical view, we conducted in-vitro experiments with HCV reperfusion of the different dialysis membranes. In our previous report, curve fitting was performed based on the results, and revealed that adsorption of the HCV antigen on the surface of dialysis membranes can be explained by the mathematical model of Langmuirs adsorption isotherm. Therefore, in order to verify the usefulness of this mathematical model in a clinical study, we investigated the elimination dynamics for HCV antigens levels of pre- and post-dialysis using the same dialysis membrane, which consist of regenerated cellulose membranes (CU; AM-FP1.3),cellulose triacetate membranes (CTA; FB-150E), polymethylmethacrylate membranes (PMMA; BK-1.6P), or polysulfone membranes (PS; F-70S) for the clinical experiment. We predicted the HCV antigen levels of post-dialysis from the HCV antigen levels of pre-dialysis by the mathematical model of the Langmuirs adsorption isotherm. The results showed that HCV antigen levels decreased after dialysis in all cases of dialysis membranes. The coefficients of adsorption rate were 0.651±0.056, 0.654±0.066 with the two cases of the PS membranes, similar results were obtained with the results from the in-vitro experiment, 1.007±0.065 with the CTA membranes, and 1.320±0.1337 with the CU membranes. Correlation coefficient between measured and theoretical values of HCV antigen levels were over 0.97 with the PS, CTA, CU membrane cases. Also the coefficient of adsorption rate of the PMMA membranes was 0.838±0.076. The correlation coefficient between measured and theoretical levels of HCV antigen levels were 0.70 or less, and a result suggested that adsorption and desorption of the HCV antigen in clinical use was repeated. In conclusion, we confirmed the high adsorption of HCV antigen with the PS membrane and the usefulness of Langmuirs adsorption isotherm was suggested in clinical dialysis.

Nature of the filtration coefficients of the microvasculature in the vicinity of dry weight in hemodialysis patients - as a marker of the fluid status

Plasma refilling from the extravascular compartment during hemodialysis (HD) is a major compensatory mechanism to maintain the blood pressure. Plasma refilling rates are proportional to the filtration coefficients of the microvasculature (Lpst) and colloid-osmotic pressure gradients minus hydrostatic pressure gradients. A decreasing tendency of Lpst according to the volume reduction with ultrafiltration (UF) was reported. The aim of this study is to investigate the relation of Lpst with other markers of the fluid status and to clarify that Lpst can be utilized as a marker of the fluid status of HD patients. A total of 106 patients on maintenance HD were examined. Atrial natriuretic peptide (ANP), inferior vena cava diameter by ultrasound (IVCe/BSA), and excess fluid mass (ExF/DW) by bioimpedance spectroscopy were measured at the end of HD. Blood volume change (ΔBV/TUF/DW) and Lpst in the vicinity of dry weight were calculated by means of monitoring changes of hematocrit with CRIT-LINE™. Lpst correlated significantly with ANP, IVCe/BSA, ABV/TUF/DW, and ExF/DW (0.461, 0.408, -0.479 and 0.590, P<;0.01, respectively). ExF/DW and Lpst were significantly higher in hypertensive patients at the end of HD than in nonhypertensive (-0.56±2.07 vs. 0.83±2.41%, P<;0.01, 1.17±0.86 vs. 1.77±1.21ml/mmHg/min, P<;0.01, respectively). There were significant differences in Δ BV/TUF/DW, ExF/DW, and Lpst between patients who were prone to intradialytic hypotension (IDH) and those who were not (3.27 ±1.44 vs. 2.67±1.16, P<;0.05, -1.16±1.91 vs. 0.67± 2.35%, P<;0.01, 1.00±0.90 vs. 1.68±1.14 ml/mmHg/min, P<;0.02, respectively). ExF/DW, ultrafiltration rate (UFRlDW), and ANP were independently associated with Lpst on multiple linear regression analysis (R=0.703). Therefore, Lpst may not properly reflect the volume status of a patient. We concluded that there are significant associations of Lpst with other markers indicating the fluid status in HD patients. This result suggests the potential to utilize Lpst as a tool for assessing the fluid status and determining an adequate DW. Lpst may be independently affected by the fluid status in the vicinity of DW, UFR/DW, and plasma ANP level. Because UFR and ANP have a marked impact on Lpst, it may be better to adjust Lpst with these factors for its utilization as a marker of the fluid status of HD patients.