Creation of the Forearm 3D-Model with Veins from Transversal Ultrasonography Image Sequence.

This study developed an automatic detection algorithm of vessel and skin regions in a transversal ultrasonography image on the arm. We also developed an algorithm to generate a 3D model from detected areas to assist vein puncture. In the algorithm, the vessel's candidate regions in the ultrasonography image were detected using U-Net or Mask R-CNN, which are a kind of deep learning method for segmentation. Then vessel regions were selected among the candidates based on continuous properties in an image sequence. The skin regions were also detected. The 3D polygon data was created from paired pixels in sequential images. The experiments demonstrated that Mask R-CNN could correctly estimate the branch of vessel which were difficult to identify accurate region separately using U-Net, and achieved an overall IoU of 80%. The confirmation experiment of 3D model demonstrated that generated model have enough feasibility for assessment of appropriate veins and locations for puncture.Clinical relevance-The developed 3D model generation from ultrasonography images will be useful for support to identify the appropriate veins for puncture.

Predictive Factors for Infusion Site Induration After Outpatient Chemotherapy in Japan: A Secondary Analysis.

PURPOSE: Even in the absence of extravasation, some patients develop induration at the peripheral intravenous catheterization site prior to the next day's treatment. Infusion site induration commonly affects patients who undergo repeated chemotherapy administrations. Vessel health is crucial for the continuation of chemotherapy. However, there is no effective method to prevent induration. Hence, this study aimed to investigate the factors that could cause induration for preventing its occurrence. METHODS: This study was a secondary analysis of a prospective observational study. All participants were undergoing outpatient chemotherapy. Participant characteristics and related catheterization data were collected on the treatment day as baseline, and induration incidence was recorded on the subsequent treatment day. Receiver operating characteristic (ROC) analysis was performed to determine the sensitivity and specificity of cutoff points of the vein and catheter diameter ratios for distinguishing between developed induration and not developed induration. Additionally, cox regression analysis with multiple imputation was used to investigate the factors that predicted induration. RESULTS: Seventy-one patients participated in the study. The cutoff point of the vein/catheter diameter ratio calculated using ROC analysis was ≥3.7. The ratio of larger-diameter veins to catheter diameter of ≥3.7 times was negatively associated with induration in both complete case analysis (HR: 0.11; p = 0.034) and multiple imputation analysis (HR: 0.12; p = .049). CONCLUSIONS: Selecting the vein with 3.7 times higher diameter than the catheter diameter for the catheterization site may help prevent induration on the next treatment day.

Verification study on the catheterization of an upper arm vein using the new long peripheral intravenous catheter to reduce catheter failure incidence: A randomized controlled trial.

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.

Effects of ultrasound with an automatic vessel detection system using artificial intelligence on the selection of puncture points among ultrasound beginner clinical nurses.

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 (<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.

Effectiveness of ultrasonography for peripheral catheter insertion and catheter failure prevention in visible and palpable veins.

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.

Effect of a thin-tipped short bevel needle for peripheral intravenous access on the compressive deformation and displacement of the vein: A preclinical study.

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.

Safety verification of a new peripheral intravenous catheter placed in the upper arm vein for administration of drugs with high irritant potential.

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.

Automatic vein measurement by ultrasonography to prevent peripheral intravenous catheter failure for clinical practice using artificial intelligence: development and evaluation study of an automatic detection method based on deep learning.

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.

Incidence, causes, and timing of peripheral intravenous catheter failure related to insertion timing in the treatment cycle in patients with hematological malignancies: A prospective descriptive study.

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.

Relationship between low back pain and stress urinary incontinence at 3 months postpartum.

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.

Catheter failure in the administration of hyperosmotic drugs through a peripheral vein and vascular selection: A retrospective cohort study.

This study aimed to determine whether the placement of a peripheral intravenous catheter (PIVC) in the cephalic vein of the forearm could prevent PIVC failure in patients receiving hyperosmotic drugs through the peripheral vein. This retrospective cohort study included patients aged ≥ 20 years who had received infusion therapy via a PIVC in our institution between July and November 2017. Patients were divided into groups according to PIVC insertion into the cephalic, basilic, and medial veins. PIVCs used to administer drugs with osmotic pressure ratios > 2.0 were included. The primary outcome was survival time to catheter failure. Catheter failure was defined as accidental and unplanned catheter removal. We set the cephalic vein and other veins, including the medial and basilic veins, in the forearm as cohort groups. We used the Kaplan-Meier survival curves to compare the time until catheter failure in the cohort groups. The Cox proportional hazard models were fitted, and the hazard ratios were calculated. A total of 46 catheters with hyperosmotic agents were included in the analysis. Catheter failure was observed in 25 (54.3%) cases. Time to catheter failure in patients receiving high-dose drugs via the cephalic vein was significantly longer than that in the other two groups (p < 0.01). Thus, the cephalic vein, which has a high blood flow, is the ideal site of PIVC insertion in patients receiving high drug concentrations to prevent catheter failure.

Damage to subcutaneous tissue at the catheterization site during chemotherapy: A prospective observational study using ultrasonography.

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.

Changes in the subcutaneous tissue of catheterization site from the precatheterization state to the onset of anticancer drug-induced induration: A case report.

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.

Evaluation of a thermosensitive liquid crystal film for catheterization site assessment immediately following chemotherapy administration: An observational study.

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.

A short bevel needle with a very thin tip improves vein puncture performance of peripheral intravenous catheters: An experimental study.

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.

Development of an algorithm using ultrasonography-assisted peripheral intravenous catheter placement for reducing catheter failure.

Up to 50% peripheral intravenous catheters (PIVs) are removed prematurely because of failures. Catheter failure (CF) leads to replacement and is a great concern for patients and medical staff. It is known that visualization of catheters and vessels with ultrasonography (US) during placement prevents CF. However, US is not a common technique for general nurses. In order to standardize US-assisted PIV placement techniques, an algorithm is needed. This study aimed to develop an algorithm using US-assisted PIV placement to reduce CF rate. Furthermore, to evaluate the effectiveness of the algorithm, CF rates were compared before and after intervention. A pretest-posttest study was performed. The intervention was PIV placement by 23 nurses undergoing training sessions for the algorithm. Intention to treat, per protocol analyses were applied. Logistic regression analysis was used for factor analysis. The CF rate in the pre-intervention group 35.2% (19/54) did not significantly differ from post-intervention group 33.6% (48/143) (p = 0.831), yet significantly differ from complete algorithm-use group 8.7% (2/23; p = 0.017). In factor analysis, compliance to the algorithm was significantly correlated with CF (p = 0.032). The compliance rate was low 16.1% (23/143). Algorithm compliance reduced CF by confirming appropriate catheter tip position from the insertion to the securement phase. This algorithm effectively reduced CF, however, the compliance rate was unacceptable. In order to increase the compliance rate, modified algorithm and new visualizing technology is required.

Incidence, risk factors, and assessment of induration by ultrasonography after chemotherapy administration through a peripheral intravenous catheter.

AIMS: Following chemotherapy, induration may occur. This study was conducted to survey induration incidence and risk factors, and investigation for actual condition of induration. METHODS: A cohort study was conducted for survey of incidence and risk factors, and a cross-sectional observation study was conducted to examine actual condition of induration. The sites of chemotherapy administration were recorded, and these were observed on the next treatment day. Clinical nurses judged the presence or absence of induration by palpation. The sites were observed using ultrasonography. To investigate the risk factors associated with the induration, logistic regression analysis was performed using independent variables based on univariate analysis or previous reports. RESULTS: In total, 69 patients were analyzed. The induration incidence was 17.4%, and three abnormal conditions were confirmed: subcutaneous edema, thrombosis, and thickening of the vessel wall. Breast cancer, non-vesicant drug, vein diameter, and fosaprepitant use were included in the logistic regression model. Breast cancer: odds ratio (OR) 9.25; 95 CI 1.91.-44.71; non-vesicant drug: OR 1.37; 95 CI 0.13-14.95; vein diameter: OR 0.40; 95% CI 0.16-0.97; fosaprepitant use: OR 0.16; 95% CI, 0.18-10.32. CONCLUSIONS: The induration incidence was 17.4%. Risk factors for induration following chemotherapy administration were breast cancer and smaller vein diameter. Abnormal cases of subcutaneous tissue were confirmed, including subcutaneous edema, thrombosis, and thickening of the vessel wall. Induration may be prevented by selecting larger diameter vessels using ultrasonography when catheterizing for chemotherapy.

Preventing peripheral intravenous catheter failure by reducing mechanical irritation.

Peripheral intravenous catheter failure is a significant concern in the clinical setting. We investigated the effectiveness of care protocols, including an ultrasonographic "pre-scan" for selecting a large-diameter vein before catheterization, a "post-scan" for confirming the catheter tip position after catheterization with ultrasonography, and the use of a flexible polyurethane catheter to reduce the mechanical irritation that contributes to the incidence of catheter failure. This intervention study was a non-randomized controlled trial to investigate the effectiveness of the abovementioned care protocols, the effects of which were compared to the outcomes in the control group, which received conventional care. For both groups, participants were selected from patients in two wards at the University of Tokyo in Japan between July and November 2017. Inverse probability score-based weighted methods (IPW) using propensity score were used to estimate the effectiveness of care protocols. The primary outcome was catheter failure, which was defined as accidental and unplanned catheter removal. We used Kaplan-Meier survival curves to compare rates of time until catheter failure. We analysed 189 and 233 catheters in the intervention and control groups, respectively. In the control group, 68 catheters (29.2%) were determined to have failed, whereas, in the intervention group, only 21 catheters (11.1%) failed. There was a significant difference between each group regarding the ratio of catheter failure adjusted according to IPW (p = 0.003). The relative risk reduction of the intervention for catheter failure was 0.60 (95% CI: 0.47-0.71). Care protocols, including assessment of vein diameter, vein depth, and catheter tip location using ultrasound examination for reducing mechanical irritation is a promising method to reduce catheter failure incidence.

Vascular endothelium damage from catheter-induced mechanical stimulation causes catheter sleeve formation in a rabbit model.

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.

Catheter tips are a possible resource for biological study on catheter failure.

Few studies have investigated the molecular mechanisms of catheter failure (CF). Herein, we performed histological and molecular biological analyses of the catheter tip to demonstrate its potential as a resource for biological investigation. Additionally, we searched for risk factors for the development of inflammation and coagulation, which are pathological conditions clarified by biological analysis. The CF group included 30 failed catheters involving thrombus and subcutaneous edema identified by ultrasonography. The No-CF group included 26 catheters with no complications. The removed catheter tips were fixed for hematoxylin-eosin (HE) staining with the application of a real-time reverse transcriptase polymerase chain reaction for eukaryotic 18S ribosomal RNA (rRNA), interleukin 1ß, tumor necrosis factor α, tissue plasminogen activator, and plasminogen activator inhibitor 1 (SERPINE1). HE staining identified attached nuclear cells on the inner surfaces of both CF and No-CF catheters. The 18S rRNA was amplified in all samples. The expression level of SERPINE1 was significantly higher in the CF group than in the No-CF group (p = 0.01), whereas the expression levels of other genes did not differ between the groups. Symptoms of CF associated with the expression of SERPINE1 were analyzed. The catheter being in contact with blood vessels during placement was a suggested factor related to the high expression of SERPINE1 (p = 0.04). Catheter tips are a potential resource for biological investigation, and expression analysis of the attached cells can reflect the pathological condition of the catheterized tissue. Further studies using catheter tips are required to elucidate the molecular mechanisms of CF.