Investigative study of hemodilution ratio: 4Vs for vein diameter, valve, velocity, and volumetric blood flow as factors for optimal forearm vein selection for intravenous infusion.

BACKGROUND: Multimodal research and guidelines recognize veins in the forearm used for peripheral intravenous catheter (PIVC) insertion can optimize dwell time. Yet, many PIVCs are still placed in areas of flexion or suboptimal locations such as the back of the hand causing premature failure of >50%. This study identified characteristics of the forearm cephalic vein that make the anatomical location highly successful for PIVC insertion. The goal was to increase the understanding of the human vasculature in association with fluid mechanics in veins above the wrist and below the antecubital fossa. METHODOLOGY: A prospective in-vivo study with 10 consented healthy human volunteers (HHVs) was performed with Color Pulse Wave Doppler Ultrasound that captured high-resolution video and images of vein diameter, velocity of blood flow, and location of venous valves in the forearm. RESULTS: Forearm vein diameter was not directly correlated with higher or lower Velocity of Blood Flow (0.58 cm = 3.0 cm/s). However, Volumetric Blood Flow rates tended to be lower (2.51-8.28 mL/min) with Vein Diameters smaller than 0.29 cm. Ultrasound assessments and Volumetric Blood Flow calculations confirmed natural turbulence in blood and retrograde blood reflux correlated with venous valves opening and closing. Areas of turbulence, with pulse flushing, created backflow with retrograde blood flow around and into the catheter. CONCLUSIONS: Placement of long PIVCs in the cephalic veins of the upper forearm yield adequate flow and hemodilution capacity for veins with at least a 3 to 1 hemodilution ratio. The data from this study, along with previous research, suggest that PIVC placement in the cephalic vein, based on selection criteria, may help to reduce or eliminate intravenous complications such as chemical or mechanical thrombophlebitis causing premature catheter failure. Application of these investigational principles may result in better outcomes and catheter longevity for patients who require intravenous infusions.

Evaluation of Skin Colonisation And Placement of vascular access device Exit sites (ESCAPE Study).

BACKGROUND: Skin microorganisms may contribute to the development of vascular access device (VAD) infections. Baseline skin microorganism type and quantity vary between body sites, yet there is little evidence to inform choice of VAD site selection. OBJECTIVE: To compare microorganisms present at different body sites used for VAD insertions and understand the effect of transparent dressings on skin microflora. METHODS: The ESCAPE observational study consisted of three phases: (1) skin swabs of four sites (mid-neck, base neck, chest, upper arm) from 48 hospital patients; (2) skin swabs of five body sites (mid-neck, base neck, chest, upper arm, lower arm) from 10 healthy volunteers; and (3) paired skin swabs (n = 72) under and outside of transparent dressings from 36 hospital patients (16 mid/base neck, 10 chest, upper arm). Specimens were cultured for 72 h, species identified and colony-forming units (CFU) counted. Ordinal logistic regression compared CFU categories between variables of interest. RESULTS: The chest and upper arm were significantly associated with fewer microorganisms compared to neck or forearm (odds ratio [OR] = 0.40, 95% confidence interval [CI] = 0.25-0.65, P < 0.05). CFU levels under transparent dressings were not significantly different from outside (OR = 0.57, 95% CI = 0.22-1.45). Staphylococci were predominant at all sites. Other significant (P < 0.05) predictors of higher CFU count included prolonged hospitalisation and medical/surgical patient status. DISCUSSION: Skin microorganism load was significantly lower at the upper arm or chest, compared to the mid- or base neck. This may impact VAD site selection and subsequent infection risk.

Vessel Health and Preservation: a model and clinical pathway for using vascular access devices.

Use of intravenous devices for the delivery of medical treatment spans all healthcare facilities ranging from hospitals to clinics and home care. Clinical pathways are processes used by healthcare providers to integrate and illustrate the best evidence and approach to care for a specific area of practice. The Vessel Health and Preservation (VHP) model is a framework and pathway process, consisting of four quadrants, to guide initiation and management of treatment requiring intravenous access. The pathway is designed to promote preservation of the vasculature of patients from admission through discharge with a focus on acute care. This article describes the model and pathway process. Moving through the quadrants of assessment/selection, insertion, management and evaluation of outcomes the clinician receives vascular access education to establish an understanding of the key principles and is then better able to provide care to the patient. Research on the VHP model has found that patients, clinicians and healthcare facilities benefit from the evidence integrated within the VHP model for improved outcomes, greater success with insertion, time saved through improved efficiency, risk reduced through appropriate device discontinuation, and greater patient satisfaction.

Quantitative assessment of reflux in commercially available needle-free IV connectors.

INTRODUCTION: Blood reflux is caused by changes in pressure within intravascular catheters upon connection or disconnection of a syringe or intravenous tubing from a needle-free connector (NFC). Changes in pressure, differing with each brand of NFC, may result in fluid movement and blood reflux that can contribute to intraluminal catheter occlusions and increase the potential for central-line associated bloodstream infections (CLABSI). METHODS: In this study, 14 NFC brands representing each of the four market-categories of NFCs were selected for evaluation of fluid movement occurring during connection and disconnection of a syringe. Study objectives were to 1) theoretically estimate amount of blood reflux volume in microliters (µL) permitted by each NFC based on exact component measurements, and 2) experimentally measure NFC volume of fluid movement for disconnection reflux of negative, neutral and anti-reflux NFC and fluid movement for connection reflux of positive displacement NFC. RESULTS: The results demonstrated fluid movement/reflux volumes of 9.73 µL to 50.34 µL for negative displacement, 3.60 µL to 10.80 µL for neutral displacement, and 0.02 µL to 1.73 µL for pressure-activated anti-reflux NFC. Separate experiment was performed measuring connection reflux of 18.23 µL to 38.83 µL for positive displacement NFC connectors. CONCLUSIONS: This study revealed significant differences in reflux volumes for fluid displacement based on NFC design. While more research is needed on effects of blood reflux in catheters and NFCs, results highlight the need to consider NFCs based on performance of individual connector designs, rather than manufacturer designation of positive, negative and neutral marketing categories for NFCs without anti-reflux mechanisms.

Report of Modification for Peripherally Inserted Central Catheter Placement: Subcutaneous Needle Tunnel for High Upper Arm Placement.

The majority of peripherally inserted central catheters (PICCs) are currently inserted with the aid of ultrasound guidance in the middle third of the upper arm. A growing patient population is presenting with challenging vessel access requiring placement of the PICC in the high upper third of the arm. To avoid this suboptimal exit site, a subcutaneous tunneling of the PICC is established away from the axilla to a more appropriate skin exit site. A prospective evaluation was performed in a single facility for all PICC placements from September 2014 to June 2015. Of the results of 685 PICC requests received during the study, 50 (7.2%) were placed with the modified Seldinger tunneling technique with 96% success. There were no reports of increased pain, insertion complications, or therapy failures. Subcutaneous tunneling, when applied to bedside PICC insertions, provides a safe, effective, and cost-efficient option for a select, more challenging patient population.

Disinfection of Needleless Connector Hubs: Clinical Evidence Systematic Review.

Background. Needleless connectors (NC) are used on virtually all intravascular devices, providing an easy access point for infusion connection. Colonization of NC is considered the cause of 50% of postinsertion catheter-related infections. Breaks in aseptic technique, from failure to disinfect, result in contamination and subsequent biofilm formation within NC and catheters increasing the potential for infection of central and peripheral catheters. Methods. This systematic review evaluated 140 studies and 34 abstracts on NC disinfection practices, the impact of hub contamination on infection, and measures of education and compliance. Results. The greatest risk for contamination of the catheter after insertion is the NC with 33-45% contaminated, and compliance with disinfection as low as 10%. The optimal technique or disinfection time has not been identified, although scrubbing with 70% alcohol for 5-60 seconds is recommended. Studies have reported statistically significant results in infection reduction when passive alcohol disinfection caps are used (48-86% reduction). Clinical Implications. It is critical for healthcare facilities and clinicians to take responsibility for compliance with basic principles of asepsis compliance, to involve frontline staff in strategies, to facilitate education that promotes understanding of the consequences of failure, and to comply with the standard of care for hub disinfection.

Is the pH of vancomycin an indication for central venous access?

All vascular access devices (VADs) have associated risks and benefits. Therefore, the decision to place a particular VAD rests on the assumption that the benefits of that device will outweigh the risks and allow for effective delivery of the treatment plan. The study by Caparas and colleagues, in the present issue of JVA, challenges the pH restrictions presented in the Standards. Caparas and her team have reconfirmed the previously reported findings that peripheral venous administration of vancomycin carries a low risk of phlebitis and extravasation and an even lower risk of catheter-related bloodstream infection. Central venous administration of vancomycin, on the other hand, carries the greater risk of central line associated bloodstream infection and deep vein thrombosis (DVT). In light of these findings and a lack of evidence to the contrary, the decision to place a central venous access device based solely on the pH of the intended therapy, vancomycin in particular, is not supported by the evidence and findings of this study. From a risk-benefit perspective, based on Caparas's study evidence, midline catheters are a safe option for patients for the administration of vancomycin, under specific concentrations, and for many other indicated medications and solutions.

Vessel health and preservation (Part 1): a new evidence-based approach to vascular access selection and management.

Vascular access for the infusion of medications and solutions requires timely assessment, planning, insertion, and assessment. Traditional vascular access is reactive, painful, and ineffective, often resulting in the exhaustion of peripheral veins prior to consideration of other access options. Evidence suggests clinical pathways improve outcomes by reducing variations and establishing processes to assess and coordinate care, minimizing fragmentation and cost. Implementation of a vascular access clinical pathway leads to the intentional selection of the best vascular access device for the patient specific to the individual diagnosis, treatment plan, current medical condition, and the patient's vessel health (1). The Vessel Health and Preservation (VHP) programme incorporates evidence-based practices focused on timely, intentional proactive device selection implemented within 24 hours of admission into any acute facility. VHP is an all-inclusive clinical pathway, guiding clinicians from device selection through patient discharge, including daily assessment. Initiation of the VHP programme within a facility provides a systematic pathway to improve vascular access selection and patient care, allowing for the reduction of variations and roadblocks in care while increasing positive patient outcomes and satisfaction. Patient safety and preservation of vessel health is the ultimate goal.