村山 陵子

OBJECTIVES: We aimed to determine (1) the prevalence of constipation among inpatients, (2) the prevalence and symptoms of difficult defecation among constipated inpatients, and (3) the factors associated with constipation. METHODS: We performed a retrospective cohort study over a single day at one university hospital. We analyzed the nursing records for inpatients who had been hospitalized for at least 3 days. The survey items included the symptoms associated with defecation difficulty and nutritional intake. The symptoms of difficult defecation were defined as (1) fewer than three spontaneous bowel movements per week; (2) lumpy or hard stools (Bristol stool form scale types 1-2); (3) straining during defecation; and (4) the sensation of incomplete evacuation during defecation, based on the Roma-IV diagnostic criteria. Constipation was defined as the presence of two or more symptoms of defecation difficulty. Univariate and multivariate analyses were performed to determine the constipation status of the patients. RESULTS: The prevalence of constipation in the university hospital was 12.2%, and the department with the highest prevalence of difficulty with defecation was the Psychiatry Department (64.1%). Of the patients with constipation, 36.8% exhibited symptoms of defecation difficulty other than low frequency of defecation. The factor that was significantly associated with constipation after admission was pre-admission constipation (odds ratio=8.92, p<0.01). CONCLUSIONS: Subjective assessment has limitations for the accurate determination of constipation status. In addition, patients with a history of constipation before admission require early interventions to aid defecation following their admission.

Intravenous infusion using a peripheral intravenous catheter (PIVC) is often complicated by catheter failure (CF). We hypothesized that catheterization of an upper arm vein instead of a forearm vein may help prevent CF. This study was designed to compare the incidence of CF in patients receiving hyper-stimulant drugs when catheters are placed in the forearm using short PIVCs (SPCs) with that when catheters are placed in the upper arm using the new long PIVCs. Patients admitted to a university hospital in Tokyo, Japan were enrolled in this study and were assigned to the SPC or the new long PIVC group. The primary outcome was the incidence of CF until 7 days. The secondary outcomes were the number of CFs per 1,000 days, the duration of the indwelling catheter, and the presence of thrombi and subcutaneous edema. Forty-seven patients were analyzed (median age, 67.0 years). The incidence of CF was 0% in the new long PIVCs and 32.0% (8 catheters) in the SPCs (p = 0.007), and the number of CF per 1,000 days was 0/1,000 and 81.7/1,000 days, respectively (p = 0.001). A significant difference in the duration of the indwelling catheter until CF occurrence was observed between the two groups (p = 0.004). Thrombi and subcutaneous edema were observed more frequently in the SPC group (p < 0.001). Catheterization of an upper arm vein using the new long PIVC to administer a hyper-stimulant drug might reduce CF compared with catheterization of a forearm vein using SPC.

Background: Ultrasound guidance increases the success rate of peripheral intravenous catheter placement. However, the longer time required to obtain ultrasound-guided access poses difficulties for ultrasound beginners. Notably, interpretation of ultrasonographic images is considered as one of the main reasons of difficulty in using ultrasound for catheter placement. Therefore, an automatic vessel detection system (AVDS) using artificial intelligence was developed. This study aimed to investigate the effectiveness of AVDS for ultrasound beginners in selecting puncture points and determine suitable users for this system. Methods: In this crossover experiment involving the use of ultrasound with and without AVDS, we enrolled 10 clinical nurses, including 5 with some experience in peripheral intravenous catheterization using ultrasound-aided methods (categorized as ultrasound beginners) and 5 with no experience in ultrasound and less experience in peripheral intravenous catheterization using conventional methods (categorized as inexperienced). These participants chose two puncture points (those with the largest and second largest diameter) as ideal in each forearm of a healthy volunteer. The results of this study were the time required for the selection of puncture points and the vein diameter of the selected points. Results: Among ultrasound beginners, the time required for puncture point selection in the right forearm second candidate vein with a small diameter (&lt;3 mm) was significantly shorter when using ultrasound with AVDS than when using it without AVDS (mean, 87 vs 247 s). Among inexperienced nurses, no significant difference in the time required for all puncture point selections was found between the use of ultrasound with and without AVDS. In the vein diameter, significant difference was shown only in the absolute difference at left second candidate among inexperienced participants. Conclusion: Ultrasonography beginners needed less time to select the puncture points in a small diameter vein using ultrasound with AVDS than without AVDS.

Despite the widespread use of peripheral intravenous catheters, unscheduled catheter failure before completion of treatment occurs frequently. If a large vein is selected, catheter failures may be prevented despite administering a highly irritant drug. In this study, we attempted to use a catheter that can be placed in a large upper arm vein. The new catheter was 88 mm long but had no guidewire to reduce contamination risk. This study aimed to evaluate the safety of the first-in-human trial for the new catheter with the administration of highly irritant drugs. This study was conducted at a university hospital in Tokyo, Japan. Eight Japanese adults were hospitalized adults with planned administration of non-cancer drugs with high irritant potential using a peripheral catheter. A trained nurse catheterized with the new catheter in the upper arm using ultrasonography. The catheterization site was monitored by staff and a research nurse once every 24 hours for up to 7 days. No adverse events or catheter failure occurred and the catheter placement success rate was 100%. In two patients, a temporary occlusion alarm of the infusion pump occurred, possibly due to the flexion of the catheter base. The new peripheral intravenous catheter did not interrupt medical treatments as is common after placement, but safety administered the irritant drugs. However, because this catheter may be easily affected by the contraction of the muscle at the fixation position, the position and method of catheter fixation in the upper arm need to be carefully considered.

Background: Peripheral intravenous catheter (PIVC) insertion often fails on the first attempt. Risk factors include small vein size and dehydration, causing vein deformation and displacement due to puncture resistance of the vessel. The authors developed a short, thin-tipped bevel needle and compared its puncture performance with needles of four available PIVCs using an ex vivo model. Methods: The PIVC with the thin-tipped short bevel needle was compared to four available PIVCs using an ex vivo model which simulated the cephalic vein of the human forearm. The ex vivo model consisted of a porcine shoulder and porcine internal jugular vein, and was used for evaluation of the rate of vein deformation and vessel displacement during needle insertion. Results: An ex vivo model was created with a vessel diameter of 2.7–3.7 mm and a depth of 2–5 mm. The thin-tipped short bevel PIVC needle was associated with a significantly lower compressive deformation rate and venous displacement compared to the needles of the other four PIVCs. Conclusion: The thin-tipped short bevel needle induced lower compressive deformation and displacement of the vein than the conventional needles. This needle has the potential to improve the first-attempt success rate of peripheral intravenous catheterization in patients with difficult venous access.

OBJECTIVES: Complications due to peripheral intravenous catheters (PIVC) can be assessed using ultrasound imaging; however, it is not routinely conducted due to the need for training in image reading techniques. This study aimed to develop and validate a system that automatically measures blood vessel diameters on ultrasound images using artificial intelligence (AI) and provide recommendations for selecting an implantation site. DESIGN: Pilot study. SETTING: The University of Tokyo Hospital, Japan. PRIMARY AND SECONDARY OUTCOME MEASURES: First, based on previous studies, the vessel diameter was calculated as the mean value of the maximum long diameter plus the maximum short diameter orthogonal to it. Second, the size of the PIVC to be recommended was evaluated based on previous studies. For the development and validation of an automatic detection tool, we used a fully convoluted network for automatic estimation of vein location and diameter. The agreement between manually generated correct data and automatically estimated data was assessed using Pearson's product correlation coefficient, systematic error was identified using the Bland-Altman plot, and agreement between catheter sizes recommended by the research nurse and those recommended by the system was evaluated. RESULTS: Through supervised machine learning, automated determination was performed using 998 ultrasound images, of which 739 and 259 were used as the training and test data set, respectively. There were 24 false-negatives indicating no arteries detected and 178 true-positives indicating correct detection. Correlation of the results between the system and the nurse was calculated from the 178 images detected (r=0.843); no systematic error was identified. The agreement between the sizes of the PIVC recommended by the research nurse and the system was 70.2%; 7% were underestimated and 21.9% were overestimated. CONCLUSIONS: Our automated AI-based image processing system may aid nurses in assessing peripheral veins using ultrasound images for catheterisation; however, further studies are still warranted.t.

AIM: We aimed to reveal detailed descriptive data on peripheral intravenous catheter (PIVC) failure related to insertion timing during the treatment cycle, in patients with lymphoma, leukemia, and myeloma. METHODS: We conducted a prospective descriptive study to investigate the incidence of PIVC failure, defined as PIVC removal prior to completing infusion therapy. This was judged by ward nurses for adult patients requiring PIVC insertion for chemotherapy. A research nurse confirmed the timing and determined the causes of PIVC failure using ultrasonographic imaging. Descriptive data were collected in the hematology and oncology ward of a tertiary hospital in Japan. RESULTS: We recruited 85 patients (with 303 PIVCs), and analyzed 67 patients (with 280 PIVCs). Of these, 118 PIVCs (42%) were inserted during the chemotherapeutic dosing period of the treatment cycle, and 106 (38%), during the rest period. The incidence of cumulative PIVC failure was 43.2% of all analyzed PIVCs (89.97 per 1,000 PIVC days). Of the PIVCs in patients with lymphoma, those inserted during the dosing period were less likely to show PIVC failure (32% vs. 57%, p < .001). Conversely, those inserted after the treatment cycle were more likely to show PIVC failure (22% vs. 7%, p = .002). CONCLUSION: This study demonstrated that the incidence of PIVC failure in patients with hematological malignancies was unacceptably high. Conceivably, the incidence of PIVC failure varies by the onset time of side effects in the treatment cycle. This should be considered when using PIVCs and selecting optimal vascular access devices for patients with hematological malignancies.

Previous studies have proposed that pelvic misalignment may be associated with stress urinary incontinence through a decrease in the contractile function of the pelvic floor muscles; however, this relationship remains unclear. This study aimed to clarify the relationship between low back pain, an indication of pelvic misalignment, and stress urinary incontinence at 3 months postpartum. We conducted a cross-sectional study of women who gave birth to full-term babies between July 2008 and July 2009. Stress urinary incontinence was defined as urinary leakage when coughing, sneezing, or exercising. Low back pain was defined as pain between the ribs and gluteal sulcus in the preceding 2 months. Of the 228 subjects included in the study, the prevalence of stress urinary incontinence was 22.8% (n = 52). The prevalence of low back pain in the stress urinary incontinence group was significantly higher than that in the non-stress urinary incontinence group (78.8% [n = 41] vs. 57.4% [n = 101]; p = 0.005). Stress urinary incontinence was associated with older age, primiparity, vaginal delivery, and low back pain at 3 months. In conclusion, low back pain was associated with stress urinary incontinence after adjusting for pregnancy and delivery factors, suggesting pelvic misalignment contributes to the development of stress urinary incontinence. We propose that including care for pelvic misalignment in pelvic floor muscle training, the treatment of choice for stress urinary incontinence, could be beneficial.

PURPOSE: Chemotherapy administration can affect subcutaneous tissue at the catheterization site with no macroscopic signs or subjective symptoms. Yet clinical studies about the impact of chemotherapy on tissue at the catheterization site, except for apparent extravasation cases, are limited. This study aimed to investigate subcutaneous tissue changes in nonmacroscopically damaged catheterization sites after chemotherapy administration. METHODS: Participants were people with cancer receiving outpatient chemotherapy. Ultrasonographic images were used to assess the condition of subcutaneous tissues, including the vein, at the catheterization site before catheterization, immediately after chemotherapy, and on the next scheduled treatment day. Data on macroscopic inspection, palpation, and subjective symptoms were also collected and analyzed. RESULTS: Data from 41 participants were analyzed. All had normal subcutaneous tissues before catheterization. After treatment, 16 (39.0%) manifested abnormalities such as subcutaneous edema, vessel wall thickening, and/or thrombosis; there was no extravasation immediately after treatment. On the next treatment day, 15 (36.6.%) showed persistent or new onset of abnormalities, including subcutaneous edema. Eight of the 15 did not exhibit any subjective symptoms or macroscopic or palpation findings. CONCLUSION: After chemotherapy administration via peripheral intravenous catheters, it was found that this damage, which was difficult to detect by the conventional assessment method, persisted. Ultrasonography can provide useful information to avoid reusing damaged sites for chemotherapy administration.

BACKGROUND: The increase in the success rate of peripheral intravenous catheterization against a difficult intravenous access (DIVA) using ultrasonography is reported; however, reports related to the effectiveness of using ultrasonography in increasing the success rate for visible and palpable veins is limited. Furthermore, according to a previous study, first attempt success in catheterization contributes to low catheter failure incidence. Thus, we developed a catheterization method using ultrasonography for peripheral veins including visible and palpable veins. This study investigates the effectiveness of ultrasonography use in improving the success rate of catheterization and preventing the catheter failure for peripheral veins including visible and palpable veins. METHODS: Adult inpatients were recruited. Trained nurses inserted intravenous catheters using ultrasonography. Ultrasonography was used for all vein assessment, target vein selection, and puncturing (i.e. target point selection and/or needle guidance), regardless of the target vein's visibility or palpability. Catheters with over a 24-h dwelling time were followed for catheter failure incidence. RESULTS: Thirty-one patients were recruited, and they required 34 catheterizations. Total number of catheterization attempts were 39. Of the peripheral veins, 51.3% (20/39) were visible and palpable, 48.7% (19/39) were DIVA. The rate of successful intravenous cannulation was 29 of 34 (85.3%) after one attempt and 4 of 34 (total 97.0%) after two attempts. The catheterization failure incidence was 3.2% (1/31) in the catheter that had an over 24-h dwelling time. CONCLUSIONS: Using ultrasonography to all target veins might have contributed to higher success rates of catheterization and extremely low incidence of catheter failure based on objective findings. Selecting the vein with larger diameters and healthy tissue as puncture point and showing center of vessel lumen clearly using ultrasonography might have been contributed the results.

This case showed that anticancer drug administration induces unhealthy subcutaneous tissue (thrombus or edema) without subjective symptoms, abnormal sign by palpation, or inspection, which have an extravasation risk.

BACKGROUND: Peripheral intravenous catheter placement is frequently unsuccessful at the first attempt. One suggested risk factor is a small vein size, because of the consequences of mechanical forces generated by the needle tip. We developed short bevel needles with a very thin tip and evaluated their puncture performance in two in vitro models. METHODS: Peripheral intravenous catheters with a new needle ground using the lancet method (experimental catheter (L)) or backcut method (experimental catheter (B)) were compared with a conventional peripheral intravenous catheter (Surshield Surflo®) in a penetration force test and a tube puncture test. Penetration forces were measured when peripheral intravenous catheters penetrated a polyethylene sheet. The tube puncture test was used to evaluate whether the peripheral intravenous catheters could puncture a polyvinyl chloride tube at two positions, at the center and at 0.5 mm from the center of the tube. RESULTS: Mean penetration forces at the needle tip produced by experimental catheters (L) (0.05 N) and (B) (0.04 N) were significantly lower than those produced by the conventional catheter (0.09 N) (p < 0.01). At the catheter tip, mean forces produced by experimental catheter (B) and the conventional catheter were 0.16 N and 0.26 N, respectively (p < 0.05). In the tube puncture test, the frequency at which the conventional catheter punctured the center-shifted site on the tube at an angle of 20° and speed of 50 mm/min was low (40%). In contrast, experimental catheters (L) and (B) were 100% successful at puncturing both the center and center-shifted sites at 20°. CONCLUSION: Puncture performance was comparable between the lancet-ground and backcut-ground needles except for penetration forces at the catheter tip. The experimental catheters produced lower penetration forces and induced puncture without target displacement at smaller angles compared with the conventional catheter. Therefore, optimization of the needle can prevent vein deformation and movement, which may increase the first-attempt success rate.

PURPOSE: Extravasation incidence is exceptionally low; however, ulceration or necrosis occurs in severe cases, possibly requiring surgical treatment. Early extravasation signs and symptoms are not always evident on treatment day, and inflammation, which leads to ulceration or necrosis, may appear several days later. Therefore, to minimize damage, identification of high-risk groups is required. This study aims to investigate the relationship between subcutaneous edema which is an early extravasation sign, and skin surface temperature using a thermosensitive liquid crystal film. METHODS: Patients receiving chemotherapy through a peripheral intravenous catheter were recruited. Subcutaneous tissue around the catheterization site was observed for the presence of subcutaneous edema by ultrasonography. During chemotherapy initiation, a thermosensitive liquid crystal film was placed on the catheterization site. Color changes of the film were observed, and each case was classified according to low-temperature distribution patterns. To investigate the factors associated with temperature distribution pattern, logistic regression analysis was performed using clinically selected independent variables. RESULTS: Data from 63 patients were analyzed. No obvious extravasation was observed. Film analysis revealed 34 cases of broadening low-temperature area from the vein and 23 cases of non-broadening low-temperature area from the vein. Subcutaneous edema was observed in 18 patients: 17 with broadening low-temperature area from the vein and 1 with non-broadening low-temperature area from the vein. Subcutaneous edema was positively correlated with broadening low-temperature area from the vein. CONCLUSION: Catheter site skin temperature distribution pattern during chemotherapy was associated with subcutaneous edema which is the early extravasation sign immediately after chemotherapy.

BACKGROUND: Intravenous catheters are widely used but are often removed due to complications associated with catheter sleeve formation. A catheter sleeve can develop from a thrombus, and catheter-induced vascular endothelium damage may be a critical factor for thrombus formation. We investigated the effect of catheter-induced mechanical stimulation on venous endothelial cells and catheter sleeve formation and the efficacy of anti-thrombogenic technology for preventing catheter sleeve formation in vivo. METHODS: We surgically implanted poly(2-methoxyethyl acrylate)-coated and uncoated catheters with and without a stylet into the right external jugular vein of a rabbit model for 14 days. Catheter sleeve formation and the ratio of residual venous endothelial cells were compared using histological examination and immunostaining with an anti-CD31 antibody, respectively. RESULTS: Stiffening an uncoated catheter with a stylet induced catheter sleeve formation along more than two-thirds of the length of the catheter. The ratios of residual venous endothelial cells at the tip of uncoated catheters with and without a stylet were 3% and 36%, respectively. While poly(2-methoxyethyl acrylate) coating also reduced the ratio of venous endothelial cells at the tip of the stiffened catheter (12%), it prevented external thrombus and catheter sleeve formation. CONCLUSION: High levels of mechanical stimulation can affect catheter-related thrombosis and promote catheter sleeve formation, and anti-thrombogenic technology such as a poly(2-methoxyethyl acrylate) coating reduces thrombus formation and can prevent catheter sleeve formation on stiffened catheters. Further studies are required to determine the maximum degree of venous endothelial cell damage before catheter sleeve formation and to compare other anti-thrombogenic technologies with poly(2-methoxyethyl acrylate) for preventing catheter sleeve formation.

Paclitaxel, a taxane, is frequently administered intravenously as an anticancer agent. When a peripheral intravenous catheter is used for paclitaxel infusion, clinical nurses often observe signs such as slight swelling at the catheter placement site, lack of blood return, and difficulty in continuing the infusion. However, the cause(s) of such phenomena at the puncture site has not yet been elucidated. The aim of this study was to obtain ultrasonography images of subcutaneous tissues and veins of patients undergoing paclitaxel and carboplatin chemotherapy and compare ultrasonography images taken immediately before catheter removal with those of patients receiving other types of taxanes. We studied 24 patients receiving chemotherapy, including seven receiving paclitaxel and carboplatin chemotherapy, through a peripheral intravenous catheter in a chemotherapy unit for outpatients of a university hospital in Japan. Ultrasonography images of venipuncture sites were obtained before catheter insertion and immediately before catheter removal. We observed subcutaneous edema in the absence of visible manifestations at the puncture sites of all patients undergoing paclitaxel and carboplatin chemotherapy, but not in any patients receiving other types of taxanes. When vesicant agents and vehicles have caused subclinical subcutaneous edema, clinical nurses may detect early slight extravasation by using ultrasonography.

Blood sampling for self-monitoring of blood glucose is difficult for the elderly with low dexterity. We developed and tested the utility of an automatic puncturing and sampling (APS) system as a part of an automatic SMBG device, but success rates of securing sufficient blood volume was low (61.9%). Thus, the squeezing condition was changed to increase its success rate. The aim of this study is to investigate the impact to the amount of bleeding by making changes to the squeezing condition. In our previous experiment, blood sampling was performed simultaneously with squeezing, whereas the present study tested blood sampling after squeezing. This method increased the success rate (75%) among eight subjects who had a low success rate (25%) in the previous experiment using the APS system.

Dietary under-reporting is a common problem when using self-reported dietary assessment tools. However, there are few studies regarding under-reporting during pregnancy. This study aimed to explore the demographic and psychosocial characteristics related to dietary under-reporting in pregnant Japanese women. A cross-sectional study was conducted between 2010 and 2011 at a university hospital in Tokyo, Japan. Nutrient intake was assessed using a self-administered Diet History Questionnaire (DHQ), which had questions about the consumption frequency and portion size of selected food items. The 24-h urinary excretion levels of urea N and K were used as the dietary protein and K intake reference values, respectively. Under-reporting of protein and K was defined as the bottom 25 % of the reporting accuracy (the ratio of reported intake on the DHQ to the estimated intake based on urinary excretion). Under-reporters were defined as participants who under-reported both protein and K intake. Multiple logistic regression analysis was performed to examine the factors associated with under-reporters. Of 271 healthy women at 19-23 weeks of gestation, thirty-five participants (12·9 %) were identified as under-reporters. Under-reporters had a lower pre-pregnancy BMI (adjusted OR (AOR) = 0·81) and lower gestational weight gain (AOR = 0·82); they also reported managing their gestational weight gain with the aim to return to their pre-pregnancy weight soon after childbirth (AOR = 2·99). Healthcare professionals should consider the potential for dietary under-reporting and the possible related factors when assessing the dietary intakes of pregnant Japanese women using self-administered questionnaires.

The risk of peripheral intravenous catheter failure varies according to the insertion site. This study examined catheter shape just after removal to evaluate the causes of catheter failure according to site. This study was a secondary analysis of previous study data. Our observational study was conducted during a 6-month period at The University of Tokyo Hospital. Participants were hospitalized adults who received infusion therapy via a short peripheral catheter. We acquired ultrasound images of blood vessels and surrounding tissues at the catheter insertion site before catheter removal and clinical images of the removed catheters. We analyzed 184 catheters from 142 participants. There were no significant differences in the catheter failure rate (29.9%) among insertion sites. Curvature in the middle of the catheter was present in 9.2% of cases; the median bend angle at the catheter base was 9.1° (range: 0.0°-68.3°). The bend angle of catheters inserted in the upper arm was significantly greater than of catheters in the forearm (p = 0.013). Catheter curvature was related to catheter failure (14.8% of failed catheters had curvature; p = 0.035) and occlusion (35.3% of occluded catheters had curvature; p = 0.008) in upper arm and forearm placements. The median distance from the elbow to the insertion site was shorter for failed catheters than for surviving catheters. To prevent catheter failure, especially occlusion resulting from catheter curvature, a catheter should be inserted at an appropriate insertion site far from the antecubital fossa.