Novel short peripheral catheter design for prevention of thrombophlebitis

Ultrasound assessment of short peripheral catheter failure

INTRODUCTION

Short peripheral catheters (SPCs) are affected by a high complication rate that leads to catheter failure. Currently, the Visual Infusion Phlebitis score (VIP) is the most used tool to verify the presence of inflammatory complications (phlebitis and thrombophlebitis). However, ultrasound signs (US) may be an attractive alternative.

OBJECTIVE

This study aims to evaluate the sensitivity and specificity of US and VIP score = 1 in identifying and recognizing early signs of SPC failure. The time to positivity for US and VIP scores was assessed as a secondary outcome.

METHODS

An observational prospective study was conducted. In each patient, US (subcutaneous edema; fibroblastic sleeve; thrombophlebitis) and VIP of the exit site were performed every 24 h until 96 h after insertion. Compared to catheter failure, Sensitivity, Specificity, and Predictive values in both US and VIP were calculated.

RESULTS

Two hundred patients were enrolled. The presence of ultrasonic pattern suggestive of edema at 72 h (p = 0.018), fibroblastic sleeve at 24, 48, 72, and 96 h (p < 0.001), thrombosis at 48 (p < 0.001) and 72 h (p = 0.005), and at least one of an abovementioned US at all checkpoints (p < 0.001) were highly significant predictors of complications. Both US and VIP effectively detect inflammatory events; however, the US showed better sensitivity in overall checkpoints and earlier predictive ability than VIP (1.9 vs 0.47 days).

CONCLUSIONS

An ultrasound inflammatory pattern is correlated with SPC failure. An ultrasound protocol-requiring minimal training-is more effective than VIP in recognizing early signs of device failure.

Design, development and preliminary assessment in a porcine model of a novel peripheral intravenous catheter aimed at reducing early failure rates

BACKGROUND

Peripheral intravenous catheters (PIVCs) are the most commonly used invasive medical device, yet despite best efforts by end-users, PIVCs experience unacceptably high early failure rates. We aimed to design a new PIVC that reduces the early failure rate of in-dwelling PIVCs and we conducted preliminary tests to assess its efficacy and safety in a porcine model of intravenous access.

METHODS

We used computer-aided design and simulation to create a PIVC with a ramped tip geometry, which directs the infused fluid away from the vein wall; we called the design the FloRamp™. We created FloRamp prototypes (test device) and tested them against a market-leading device (BD Insyte™; control device) in a highly-controlled setting with five insertion sites per device in four pigs. We measured resistance to infusion and visual infusion phlebitis (VIP) every 6 h and terminated the experiment at 48 h. Veins were harvested for histology and seven pathological markers were assessed.

RESULTS

Computer simulations showed that the optimum FloRamp tip reduced maximum endothelial shear stress by 60%, from 12.7 Pa to 5.1 Pa, compared to a typical PIVC tip and improved the infusion dynamics of saline in the blood stream. In the animal study, we found that 2/5 of the control devices were occluded after 24 h, whereas all test devices remained patent and functional. The FloRamp created less resistance to infusion (0.73 ± 0.81 vs 0.47 ± 0.50, p = 0.06) and lower VIP scores (0.60 ± 0.93 vs 0.31 ± 0.70, p = 0.09) than the control device, although neither findings were significantly different. Histopathology revealed that 5/7 of the assessed markers were lower in veins with the FloRamp.

CONCLUSIONS

Herein we report preliminary assessment of a novel PIVC design, which could be advantageous in clinical settings through decreased device occlusion and reduced early failure rates.

A temperature-responsive intravenous needle that irreversibly softens on insertion

The high stiffness of intravenous needles can cause tissue injury and increase the risk of transmission of blood-borne pathogens through accidental needlesticks. Here we describe the development and performance of an intravenous needle whose stiffness and shape depend on body temperature. The needle is sufficiently stiff for insertion into soft tissue yet becomes irreversibly flexible after insertion, adapting to the shape of the blood vessel and reducing the risk of needlestick injury on removal, as we show in vein phantoms and ex vivo porcine tissue. In mice, the needles had similar fluid-delivery performance and caused substantially less inflammation than commercial devices for intravenous access of similar size. We also show that an intravenous needle integrated with a thin-film temperature sensor can monitor core body temperature in mice and detect fluid leakage in porcine tissue ex vivo. Temperature-responsive intravenous needles may improve patient care.

Effect of indwelling depth of peripheral intravenous catheters on thrombophlebitis

To clarify the effect of catheter indwelling depth on the occurrence of thrombophlebitis, a total of 339 hospitalized patients were randomly enrolled and divided by the catheter indwelling depth into 2 groups. Then the effect of indwelling depth on thrombophlebitis was analyzed, and the independent influence factors on the occurrence of thrombophlebitis were clarified. There were 49 cases of thrombophlebitis, including 8 tumor-bearing patients and 41 patients with lung infection. Thirteen of the 135 patients with indwelling depth of 1 cm, and 36 of the 204 patients with indwelling depth of 1.9 cm suffered thrombophlebitis. The relationship between incidence rate of thrombophlebitis and clinicopathological parameters was analyzed. It was found the incidence of thrombophlebitis was significantly correlated with males (X2 = 5.77), lung infection (X2 = 7.79), and indwelling depth of 1.9 cm (X2 = 4.223). Multifactor analysis of variance showed the significant independent risk factors of thrombophlebitis were male [hazard ratio (HR) 3.12 (1.39-6.98)], and lung infection (HR 0.22 [0.06-0.69]), and the indwelling depth of 1.9 cm affected the occurrence of thrombophlebitis (HR 0.79 [0.42 -3.09]) but was not an independent risk factor. In our treatment center, while appropriate fixation was ensured, the catheter indwelling depth shall be as short as possible, so as to reduce the occurrence of thrombophlebitis. For patients with lung infection, nursing at the intubation site shall be strengthened, so as to decrease thrombophlebitis.

Short Peripheral Venous Catheters Contamination and the Dangers of Bloodstream Infection in Portugal: An Analytic Study

Peripheral venous catheters (PVCs) are the most used vascular access devices in the world. However, failure rates remain considerably high, with complications such as PVC-related infections posing significant threats to patients’ well-being. In Portugal, studies evaluating the contamination of these vascular medical devices and characterizing the associated microorganisms are scarce and lack insight into potential virulence factors. To address this gap, we analyzed 110 PVC tips collected in a large tertiary hospital in Portugal. Experiments followed Maki et al.’s semi-quantitative method for microbiological diagnosis. Staphylococcus spp. were subsequently studied for the antimicrobial susceptibility profile by disc diffusion method and based on the cefoxitin phenotype, were further classified into strains resistant to methicillin. Screening for the mecA gene was also done by a polymerase chain reaction and minimum inhibitory concentration (MIC)-vancomycin as determined by E-test, proteolytic and hemolytic activity on skimmed milk 1% plate and blood agar, respectively. The biofilm formation was evaluated on microplate reading through iodonitrotetrazolium chloride 95% (INT). Overall, 30% of PVCs were contaminated, and the most prevalent genus was Staphylococcus spp., 48.8%. This genus presented resistance to penicillin (91%), erythromycin (82%), ciprofloxacin (64%), and cefoxitin (59%). Thus, 59% of strains were considered resistant to methicillin; however, we detected the mecA gene in 82% of the isolates tested. Regarding the virulence factors, 36.4% presented α-hemolysis and 22.7% β-hemolysis, 63.6% presented a positive result for the production of proteases, and 63.6% presented a biofilm formation capacity. Nearly 36.4% were simultaneously resistant to methicillin and showed expression of proteases and/or hemolysins, biofilm formation, and the MIC to vancomycin were greater than 2 µg/mL. Conclusion: PVCs were mainly contaminated with Staphylococcus spp., with high pathogenicity and resistance to antibiotics. The production of virulence factors strengthens the attachment and the permanence to the catheter’s lumen. Quality improvement initiatives are needed to mitigate such results and enhance the quality and safety of the care provided in this field.

Early recognition of peripheral intravenous catheter failure using serial ultrasonographic assessments

OBJECTIVE

Peripheral intravenous catheter (PIVC) failure occurs frequently, but the underlying mechanisms of failure are poorly understood. We aim to identify ultrasonographic factors that predict impending PIVC failure prior to clinical exam.

METHODS

We conducted a single site prospective observational investigation at an academic tertiary care center. Adult emergency department (ED) patients who underwent traditional PIVC placement in the ED and required admission with an anticipated hospital length of stay greater than 48 hours were included. Ongoing daily PIVC assessments included clinical and ultrasonographic evaluations. The primary objective was to identify ultrasonographic PIVC site findings associated with an increased risk of PIVC failure. The secondary outcome was to determine if ultrasonographic indicators of PIVC failure occurred earlier than clinical recognition of PIVC failure.

RESULTS

In July and August of 2020, 62 PIVCs were enrolled. PIVC failure occurred in 24 (38.71%) participants. Multivariate logistic regression demonstrated that the presence of ultrasonographic subcutaneous edema [AOR 7.37 (1.91, 27.6) p = 0.0030] was associated with an increased likelihood of premature PIVC failure. Overall, 6 (9.67%) patients had subcutaneous edema present on clinical exam, while 35 (56.45%) had subcutaneous edema identified on ultrasound. Among patients with PIVC failure, average time to edema detectable on ultrasound was 46 hours and average time to clinical recognition of failure was 67 hours (P = < 0.0001).

CONCLUSIONS

Presence of subcutaneous edema on ultrasound is a strong predictor of PIVC failure. Subclinical subcutaneous edema occurs early and often in the course of the PIVC lifecycle with a predictive impact on PIVC failure that is inadequately captured on clinical examination of the PIVC site. The early timing of this ultrasonographic finding provides the clinician with key information to better anticipate the patient's vascular access needs. Further research investigating interventions to enhance PIVC survival once sonographic subcutaneous edema is present is needed.

Novel Design of Peripheral Infusion Catheter Improves the Kinetics of Intravenous Drug Release

Short peripheral catheters are ubiquitous in today's healthcare environment, enabling effective and direct delivery of fluids and medications intravenously. A commonly associated complication of their use is thrombophlebitis-thrombus formation-involved inflammation of the vein wall. A novel design of a very short peripheral catheter showed promising results in a pig model in reducing the mechanical irritation to the vein wall. Here, the kinetics of drug release through the novel catheter was compared to a standard commercial catheter using experimental and computational models. In a good agreement, in vitro and in silico models reveal the superiority of the novel catheter design with faster washout time, favorable spatial distribution within the vein, and substantially lower wall shear stress. We submit therefore that the novel design has an improved drug removal profile compared to the conventional catheter and can potentially reduce chemical irritation to the vein wall and minimize the risk for thrombophlebitis. CLINICAL RELEVANCE: Short peripheral catheters are ubiquitous in today's healthcare environment, allowing effective and direct delivery of fluids and medications intravenously. It is well known, however, that prolonged exposure to an irritant drug may lead to its absorption in the endothelial layer lining the vein wall, promoting among other, thrombophlebitis that may lead to increased morbidity, delayed treatment, and prolonged hospitalization. There have been multiple calls to consider low infusion rates with various infusion protocols and to place the catheter tip as central as possible to promote faster drug clearance and reduce the potential vessel damage, but the requisite device had not been available, and the short peripheral catheter is still, and for decades, the standard of care. Towards this end, we recently introduced a novel very short peripheral catheter design, and here, we demonstrate using experimental and computational models its favorable spatial and temporal drug-releasing profiles compared with the standard catheter. The clinically potential relevance is underscore both by the more efficient perfusion of IV drugs and lower irritation to the vein wall at the site of injection. Graphical abstract.

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.