Extravasation and infiltration: under-recognised complications of intravenous therapy.

Occasionally, the administration of intravenous (IV) therapies can go wrong. Infiltration or extravasation is a complication when a drug or IV therapy leaks into the tissues surrounding the vascular access device. Extravasation can cause serious and often life-changing injuries. Extravasation is often associated with systemic anti-cancer therapy but non-chemotherapy drugs have been reported as having a greater risk of serious complications. This study outlines the first UK Infusion unit evaluation of the ivWatch infusion monitoring device which was undertaken from August 2023 to January 2024. Out of 2254 infusions monitored with ivWatch, the device prevented 122 cases of infiltration and extravasation from causing any harm to the patient, corresponding to a 5.4% 'check IV' notification rate.

Hemodynamic Monitoring In The Cardiac Surgical Patient: Comparison of Three Arterial Catheters.

OBJECTIVE: Systemic systolic (SAP) and mean (MAP) arterial pressure monitoring is the cornerstone in hemodynamic management of the cardiac surgical patient, and the radial artery is the most common site of catheter placement. The present study compared 3 different arterial line procedures. It is hypothesized that a 20-G 12.7- cm catheter inserted into the radial artery will be equal to a 20-G 12.7- cm angiocath placed in the brachial artery, and superior to a 20-G 5.00 cm angiocath placed in the radial artery. DESIGN: A prospective randomized control study was performed. SETTING: Single academic university hospital. PARTICIPANTS: Adult patients ≥18 years old undergoing nonemergent cardiac surgery using cardiopulmonary bypass (CPB). INTERVENTIONS: After approval by the Rhode Island Hospital institutional review board, a randomized prospective control study to evaluate 3 different peripheral intraarterial catheter systems was performed: (1) Radial Short (RS): 20-G 5- cm catheter; (2) Radial Long (RL): 20-G 12- cm catheter; and (3) Brachial Long (BL): 20-G 12- cm catheter. MEASUREMENTS AND RESULTS: Gradients between central aortic and peripheral catheters (CA-P) were compared and analyzed before CPB and 2 and 10 minutes after separation from CPB. The placement of femoral arterial lines and administration of vasoactive medications were recorded. After exclusions, 67 BL, 61 RL, and 66 RS patients were compared. Before CPB, CA-P SAP and MAP gradients were not significant among the 3 groups. Two minutes after CPB, the CA-P SAP gradient was significant for the RS group (p = 0.005) and insignificant for BL (p = 0.47) and RL (p = 0.39). Two-group analysis revealed that CA-P SAP gradients are similar between BL and RL (p = 0.84), both of which were superior to RS (p = 0.02 and p = 0.04, respectively). At 10 minutes after CPB, the CA-P SAP gradient for RS remained significant (p = 0.004) and similar to the gradient at 2 minutes. The CA-P SAP gradients increased from 2 to 10 minutes for BL (p = 0.13) and RL (p = 0.06). Two minutes after CPB, the CA-P MAP gradients were significant for the BL (p = 0.003), RL (p < 0.0001), and RS (p < 0.0001) groups. Two-group analysis revealed that the CA-P MAP gradients were lower for the BL group compared with the RL (p = 0.054) and RS (p< 0.05) groups. Ten minutes after CPB, the CA-P MAP gradients in the RL and RS groups remained significant (p < 0.0001) and both greater than the BL group (p = 0.002). A femoral arterial line was placed more frequently in the RS group (8/66 = 12.1%) than in the RL group (3/61 = 4.9%) and the BL group (2/67 = 3.0%). Vasopressin was administered significantly more frequently in the RS group. CONCLUSION: Regarding CA-P SAP gradients, the RL group performed equally to the BL group, both being superior to RS. Regarding CA-P MAP gradients, BL was superior to RL and RS. Clinically, femoral line placement and vasopressin administration were fewer for the BL and RL groups when compared with the RS group. This study demonstrated the benefits of a long (12.7 cm) 20- G angiocath placed in the radial artery.

Vascular access device type for systemic anti-cancer therapies in cancer patients: A scoping review.

BACKGROUND: Patients with cancer can expect to receive numerous invasive vascular access procedures for intravenous therapy and clinical diagnostics. Due to the increased incidence and prevalence of cancer globally there will be significantly more people who require first-line intravenous chemotherapy over the next ten years. METHODS: Our objective was to determine the types of evidence that exist for the vascular access device (VAD) type for the delivery of systemic anti-cancer therapy (SACT) in cancer patients. We used JBI scoping review methodology to identify the types of VADs used for SACT and with a specific search strategy included articles from 2012-2022 published in the English language. We identify (i) type of VADs used for SACT delivery (ii) the type of insertion and post-insertion complications (iii) the geographical location and clinical environment (iv) and whether VAD choice impacts on quality of life (QOL). Findings were presented using the PAGER framework. MAIN FINDINGS: Our search strategy identified 10,390 titles, of these, 5318 duplicates were removed. The remaining 5072 sources were screened for eligibility, 240 articles met the inclusion criteria. The most common design include retrospective study designs (n = 91) followed by prospective study designs (n = 31). We found 28 interventional studies with 21 registered in a clinical trial registry and identified no core outcome sets papers specific to VAD for SACT. The most prevalent publications were those that featured two or more VAD types (n = 70), followed by tunnelled intravenous VADs (n = 67). Of 38 unique complications identified, the most frequent catheter related complication was catheter related thrombosis (n = 178, 74%), followed by infection (n = 170, 71%). The county where the most publications originated from was China (n = 62) with one randomized controlled multicenter study from a comprehensive cancer centre. Of the thirty three studies that included QOL we found 4 which reported on body image. No QOL measurement tools specific to the process of SACT administration via VAD are available INTERPRETATION: Our findings suggest a systematic review and meta-analysis of VAD use for intravenous SACT can be considered. However, the development of a core outcome set for SACT should be prioritised. Funding for high quality programs of research for VAD in cancer are needed. Comprehensive cancer centres should lead this research agenda.

Five-Year Safety and Effectiveness of Paclitaxel Drug-Coated Balloons Alone or With Provisional Bare Metal Stenting for Real-World Femoropopliteal Lesions: IN.PACT Global Study Subgroup Analysis.

BACKGROUND: The treatment of complex infra-inguinal disease with drug-coated balloons (DCBs) is associated with a significant number of patients undergoing provisional stenting to treat a suboptimal result. To determine the potential long-term impact of DCB treatment with provisional bare metal stenting in complex lesions in real-world patients, a post hoc analysis was performed on data from the IN.PACT Global Study (The IN.PACT Global Clinical Study for the Treatment of Comprehensive Superficial Femoral and/or Popliteal Artery Lesions Using the IN.PACT Admiral Drug-Eluting Balloon). Five-year outcomes were compared between participants who were stented after DCB treatment versus those treated with DCB alone. METHODS: The IN.PACT Global Study enrolled 1535 participants with intermittent claudication and/or ischemic rest pain caused by femoropopliteal lesions; 1397 patients were included in this subgroup analysis (353 stented and 1044 nonstented). Effectiveness was assessed as freedom from clinically driven target lesion revascularization through 60 months. The primary safety composite end point was defined as freedom from device- and procedure-related death through 30 days, and freedom from major target limb amputation and clinically driven target vessel revascularization through 60 months. RESULTS: Lesions in the stented group were longer (15.37 versus 10.98 cm; P<0.001) and had more total occlusions (54.7% versus 28.6%; P<0.001) compared with the nonstented group. The 5-year Kaplan-Meier estimated freedom from clinically driven target lesion revascularization was similar between groups (66.8% stented versus 70.0% nonstented group, log-rank P=0.22). The safety composite end point was achieved in 64.5% stented versus 68.2% nonstented participants (log-rank P=0.19) as estimated by the Kaplan-Meier method. No significant difference was observed in the cumulative incidence of major adverse events (49.1% stented versus 45.0% nonstented; log-rank P=0.17), including all-cause death (19.6% stented versus 19.3% nonstented, log-rank P=0.99). CONCLUSIONS: In this real-world study, revascularization of complex femoropopliteal artery lesions with DCB angioplasty alone or DCB followed by provisional bare metal stenting in certain lesions achieved comparable long-term safety and clinical effectiveness. REGISTRATION: URL: https://www.clinicaltrials.gov; Unique identifier: NCT01609296.

Heparin versus normal saline for the care of peripheral intravenous catheters in children: A meta-analysis.

AIM: To conduct a meta-analysis to evaluate the role of heparin versus normal saline lock in the care of peripheral intravenous catheters. DESIGN: A meta-analysis. METHODS: This meta-analysis searched nine databases for randomized controlled trials (RCTs) on heparin versus normal saline for the care of peripheral intravenous catheters in children up to April 5, 2023. The quality of included RCTs was evaluated using the risk of bias tool of Cochrane library. RevMan5.3 software was used for data analysis. RESULTS: Ten RCTs with a total of 1255 children were involved. Meta-analysis indicated that heparin lock reduced the incidence of blockage of peripheral intravenous catheter [OR = 2.01, 95% CI (1.42,2.84), p < 0.001], prolonged the duration of peripheral intravenous catheter indwelling[MD = -0.43, 95% CI (-0.75, -0.11), p = 0.008]. There were no statistical differences in the incidence of phlebitis [OR = 1.02, 95% CI (0.59, 1.74), p = 0.95 W]. PUBLIC CONTRIBUTION: Heparin may have more benefits in the nursing care of peripheral intravenous catheters compared with normal saline.

Care bundles and peripheral arterial catheters.

HIGHLIGHTS: What we know about the topic: Recommendations for the use of vascular access care bundles to reduce infection are followed for different devices. The risk of arterial catheter-related infection is comparable with short-term, non-cuffed central venous catheters. There are practice concerns for clinicians inserting and caring for peripheral arterial catheters. What this paper adds: The selected studies had a theme of decreased infection after using bundled strategies for all devices. Few studies addressed use of bundles for care of peripheral arterial catheters. High-quality research should be performed about using care bundles for insertion and care of arterial catheters. INTRODUCTION: A scoping review of the literature was performed. AIMS/OBJECTIVES: To find information on the use of care bundles for care of arterial, central, and peripherally inserted venous catheters. METHODS: Data was extracted by 2 independent researchers using standardized methodology. RESULTS: Results of 84 studies included 2 (2.4%) randomized controlled trials, 38 (45.2%) observational studies, 29 (34.5%) quality projects, and 15 (17.9%) reviews. Populations had more adults than pediatric patients. All studies had the most prominent theme of decreased infection in all devices after using bundle strategies. DISCUSSION AND CONCLUSIONS: The mapping of available evidence strongly supports the use of care bundles to reduce infection in the care of all intravascular devices. However, deficiencies regarding practice concerns about insertion and care of arterial catheters highlight areas for future research with the aim to eliminate the gap in the evidence of studies of care bundles for peripheral arterial catheters.

A safe and effective winged peripheral intravenous cannula for use in clinical practice.

Vascular access continues to be a key factor for the reliable and safe delivery of intravenous (IV) therapy to patients in any healthcare setting. Clinical guidelines advocate for the right vascular access device selection, in order to reduce avoidable complications, eg multiple stabs, phlebitis, thrombophlebitis, insertion site infection, and blood stream infection, while improving efficiency and reducing costs. Peripheral intravenous catheters or cannulas (PIVCs) remain widely used for gaining vascular access in all clinical settings, with both adults and children, because they provide a relatively cheap and simple way to provide blood sampling and the prompt administration of IV medications. Although safe and easy to insert, PIVCs present with associated risks that can be costly to the organisation. The case studies included with this article introduce Nipro's Safetouch Cath Winged with Injection Port as a new cost-effective choice of PIVC, which is now available from NHS Supply Chain.

Heparin vs Saline Infusion to Maintain Patency of Arterial Catheters in Children: A Randomized, Double-Blind, Noninferiority Trial.

OBJECTIVE: To determine whether normal saline flush solution is noninferior to heparinised saline for maintaining the patency of arterial intravascular catheters in children. METHODS: A single centre, double blind, parallel group, noninferiority, randomized control study was conducted in the Pediatric Intensive Care Unit of Kanchi Kamakoti CHILDS Trust hospital, a tertiary children's hospital, Chennai, India. 92 children requiring arterial catheters for more than 12 hours were randomized to receive either normal saline or heparinized saline (1 U/ml) flush solution. Primary outcome was a noninferiority comparison between normal saline and heparinised saline in maintaining the patency of arterial catheters using the proportion of occlusion of arterial catheters as primary endpoint. Secondary outcome was mean duration of patency of arterial catheters in each treatment group. RESULTS: Ninety-two children with a median (interquartile range, age of 84 (33.5-132) months and 52% males were enrolled. 15.2% of catheters in the heparin group and 17.4% of catheters in the normal saline group were occluded (P = 0.77). The 95% upper confidence interval for the difference in proportion was 0.148 (+14.8%), establishing noninferiority (< 15%). The median (IQR) duration of a patent arterial catheter was 47 (27.75 - 94.5) hours in the heparin group and 35.50 (24.50 - 62) hours in the normal saline group (P = 0.10). Comparison of duration of patency using Kaplan Meier survival analysis and log rank test showed no statistically significant difference. There were no serious adverse events noted in either group. CONCLUSIONS: Our data suggests that normal saline is noninferior to heparinized saline infusion in maintaining the patency of arterial lines in children. This may benefit clinicians worldwide as normal saline would be a safer and cost-effective option.

Recanalization of Chronic Femoropopliteal Total Occlusions after Failed Anterograde Attempt: Use of an Intravascular Ultrasound-Guided Re-entry Catheter versus the Bidirectional Approach.

PURPOSE: To analyze the feasibility and effectiveness of the use of an intravascular ultrasound (IVUS)-guided re-entry catheter (IGRC) for femoropopliteal chronic total occlusions (FP-CTOs) after a failed anterograde approach compared with the bidirectional approach without the IGRC. MATERIALS AND METHODS: Between June 2019 and December 2022, an IGRC (Pioneer Plus; Philips Volcano, San Diego, California) was used in 52 patients after failure of conventional recanalization techniques (Group A). In the same period, 48 patients who were also eligible for IGRC use were treated without IGRC using the bidirectional approach (Group B). In Groups A and B, 12 (23.1%) and 3 (6.2%) patients experienced claudication, and 40 (76.9%) and 45 (93.7%) patients experienced critical limb-threatening ischemia, respectively. Clinical and procedural records, angiographic imaging findings, and follow-up data were collected, analyzed, and reviewed. RESULTS: Technical success was achieved in 49 (94.2%) patients in Group A and 44 (91.7%) patients in Group B (P = .616). Use of the IGRC was associated with a reduction of procedural time (120 vs 133 minutes; P < .001), radiation exposure (47 vs 59 Gy cm2; P < .001), iodinated contrast medium use (98 vs 138 mL; P = .028), and intraprocedural discomfort (numerical rating scale score, 4 vs 6; P < .001). CONCLUSIONS: Use of the IGRC was equivalently successful for FP-CTO recanalization compared with the use of the bidirectional approach, but it reduced radiation exposure, iodinated contrast medium used, patient discomfort, and procedural time. These advantages suggest that IGRC could be favored as the next-choice option for FP-CTOs after failure of anterograde recanalization.

Phase I Safety and Feasibility Pilot of Hepatic Artery Infusion Chemotherapy in a Rural Catchment Area Using The Codman Vascular Catheter with The Medtronic SynchroMed II Pump for Intrahepatic Cancers.

BACKGROUND: Discontinuation of the Codman 3000 pump in 2018 left no Food and Drug Administration (FDA)-approved hepatic artery infusion (HAI) device for unresectable colorectal liver metastases (uCLM) and intrahepatic cholangiocarcinoma (uIHC). Historically, HAI has been performed at academic medical centers in large metropolitan areas, which are often inaccessible to rural patients. Consequently, feasibility of dissemination of HAI to rural populations is unknown. PATIENTS AND METHODS: Under an FDA investigational device exemption, we opened the only HAI program in Kentucky and enrolled patients with uCLM and uIHC in a phase I clinical trial. The trial examined the safety of the hybrid Codman catheter/Medtronic SynchroMed II pump (hCMP) combination, defined as successful completion of one cycle of HAI chemotherapy. Rural feasibility was assessed by number of missed pump fills appointments. RESULTS: A total of 21 patients (n = 17 uCLM, n = 4 uIHC) underwent hCMP implantation before accrual was stopped early owing to FDA approval of the Intera 3000 pump. 20/21 (95%) patients met the primary safety endpoint. Serious adverse events (AEs) included a grade 5 coronavirus disease 2019 (COVID-19) infection (n = 1) and a grade 3 catheter erosion into the bowel (n = 1). Biliary sclerosis developed in two patients (9.5%). Median distance to infusion center was 47.6 miles (2-138 miles), and 62% were from Appalachia, yet there were no missed pump fill appointments. The 2-year overall survival was 82.4% (uCLM) and 50% (uIHC). CONCLUSIONS: The hCMP device had an acceptable safety profile. Despite the complexity of starting a new HAI program, early results showed feasibility for HAI delivery in a rural catchment area and comparable outcomes to larger urban-based HAI centers.

Surgical retrieval of transected umbilical vein catheter in an extremely preterm neonate.

Umbilical catheters are used in the care of critically ill neonates for intravenous treatment. It is generally considered a safe procedure, although complications can occur. Of these, catheter breakage and intravenous migration are rare but potentially life-threatening events. Due to the low frequency of which these events occur, obtaining detailed descriptions of removal techniques can pose a challenge. Here, we describe a case of a broken umbilical vein catheter and the surgical retrieval of the retained fragment. We also present a thorough literature search of cases of broken umbilical catheters and the method by which they were removed.

Foundation for implementing a comprehensive vascular access excellence initiative organization-wide to improve vascular access device insertion and standardize care: best practice for an acute care hospital.

INTRODUCTION: In 2016, a 263-bed public district hospital in California trialed a peripheral intravenous catheter (PIVC) inserted using ultrasound, with the potential to increase first attempt success in difficult intravenous access (DIVA) patients. This led to the implementation of a hospital-wide initiative to improve nursing vascular access skills and expedite vascular access device (VAD) placement. METHODS: To trial a PIVC and ultrasound-guided (USG) insertion, a training program was developed and led to a doctoral Capstone project piloting an evidence-based nurse-driven protocol for the identification of DIVA patients. A Vascular Access Committee was established to achieve vascular access excellence throughout the hospital by increasing the number of nurses with advanced skills in VAD placement and by developing a central venous access device (CVAD) insertion and maintenance bundle to decrease the incidence of central line-associated bloodstream infections (CLABSI). With ongoing support of nursing leadership and achievement of ANCC Magnet Recognition® in 2021, the hospital developed a comprehensive initiative to provide patients with a consistent level of nursing expertise for VAD placement across all shifts. RESULTS: Requests for USGPIVCs increased throughout the hospital, DIVA patients themselves requested ultrasound guidance be used for PIVC insertions, and there were fewer requests for Emergency Department (ED) physicians to insert CVADs. From the related Doctor of Nursing Practice (DNP) Capstone project, there were higher first-attempt cannulation successes, longer PIVC dwell times, and a reduction in devices and supplies utilized. The CVAD bundles resulted in the number of central line-associated bloodstream infections decreasing from four in 2019 to one in 2020. Since the initiative's inception, a total of 92 nurses completed the USGPIVC insertion training, and patient access to advanced-skilled clinicians is now available around the clock. DISCUSSION: This manuscript discusses the initiative implemented to standardize patient care through a collaborative multidisciplinary approach and has potential generalizability to other acute care hospitals to reduce associated healthcare costs and to prevent poor patient outcomes by expediting the arrival of a vascular access nurse for DIVA patients. CONCLUSION: The vascular access excellence initiative implemented provided an effective strategy to enhance the skills and confidence of nurses in VAD placement and improved efficiency in processes to expedite the arrival of an advanced skilled nurse to place VADs on DIVA. Targeted educational initiatives improved patient outcomes by reducing catheter-related bloodstream infections.

Early exploration of the economic impact of transradial access (TRA) versus transfemoral access (TFA) for neurovascular procedures in Spain.

INTRODUCTION: Transfemoral access (TFA) is the primary access approach for neurointerventional procedures. Transradial access (TRA) is established in cardiology due to its lower complications, yet, it is at its early stages in neuroprocedures. This study performs an early exploration of the economic impact associated with the introduction of TRA in diagnostic and therapeutic neuroprocedures from the Spanish NHS perspective. METHODS: An economic model was developed to estimate the cost and clinical implications of using TRA compared to TFA. Costs considered access-related, complications and recovery time costs obtained from local databases and experts' inputs. Clinical inputs were sourced from the literature. A panel of eight experts from different Spanish hospitals, validated or adjusted the values based on local experience. Hypothetical cohorts of 10,000 and 1000 patients were considered for diagnostic and therapeutic neuroprocedures respectively. Deterministic sensitivity analysis was performed. RESULTS: TRA in diagnostic procedures was associated with lower costs with savings ranging between €486 and €157 depending on the TFA recovery time considered. TRA is estimated to lead to 158 fewer access-site complications. In therapeutic procedures, TRA resulted in 76.4 fewer complications and was estimated to be cost-neutral with an incremental cost of €21.56 per patient despite recovery times were not included for this group. Variation of the parameters in the sensitivity analysis did not change the direction of the results. LIMITATIONS: Clinical data was obtained from literature validated by experts therefore results generalizability is limited. In therapeutic neuroprocedures, there is an experience imbalance between approaches and recovery times were not included hence the total impact is not fully captured. CONCLUSIONS: The early economic model suggests that implementing TRA is associated with reduced costs and complications in diagnostic procedures. In therapeutic procedures, TRA lead to fewer complications and it is estimated to be cost-neutral, however its full potential still needs to be quantified.

Vascular perforation of umbilical venous catheter and awaiting it to be shallow.

The patient was a boy born at 23 weeks and 0 days of gestation weighed 401 g at birth. For treatment, an umbilical venous catheter was placed but the catheter perforated a blood vessel. We thought that prompt removal of the catheter would lead to massive bleeding, so we kept the catheter in place at the umbilicus, waited for weight gain, and removed it after confirming that the catheter tip had spontaneously become shallow and was in the umbilical vein. This procedure allowed us to handle the patient without major problems.

Safety of Extending Implanted Vascular Access Device Maintenance Flush Frequency.

BACKGROUND: Standards of care and guidelines acknowledge insufficient evidence that defines frequency of flushing for implanted vascular access devices (IVADs). Manufacturers recommend 4 weeks, but guidelines suggest that extending to 12 weeks is safe based on functionality. OBJECTIVES: The study reviewed current standards of care for IVAD flush maintenance frequency, examined the characteristics of blood from IVADs by aspirating and observing contents prior to flushing when maintenance care is delayed beyond four weeks, and identified whether more research is required to determine optimal IVAD maintenance flush frequency. METHODS: An outpatient oncology clinic gathered data related to IVAD flush frequency during the COVID-19 pandemic. The concern was potentially harmful substances being flushed into the patient. A new method was developed to allow for observation of physiologic characteristics within the IVAD. Abnormal-appearing substances aspirated from the devices were discarded prior to use. FINDINGS: Visible clots and alterations in color and appearance were observed in 25% of the 59 patients observed between 8 and 17+ weeks when the IVAD reservoir was aspirated prior to flushing.

What Factors Are Associated With Arterial Line-Related Limb Ischemia in Patients on Extracorporeal Membrane Oxygenation? A Single-Center Retrospective Cohort Study.

OBJECTIVES: The primary purpose of this study was to identify factors associated with the development of arterial line-related limb ischemia in patients on extracorporeal membrane oxygenation (ECMO). The authors also sought to characterize and report the outcomes of patients who developed arterial line-related limb ischemia. DESIGN: Retrospective cohort study. SETTING: A single academic tertiary referral ECMO center. PARTICIPANTS: Consecutive patients who were treated with ECMO over 6 years. INTERVENTIONS: Use of arterial line. MEASUREMENTS AND MAIN RESULTS: A total of 278 consecutive ECMO patients were included, with 19 (7%) patients developing arterial line-related limb ischemia during the ECMO run. Postcannulation Sequential Organ Failure Assessment (SOFA) (adjusted odds ratio [aOR] 1.20, 95% CI 1.08-1.32), Acute Physiology and Chronic Health Evaluation-II (aOR 0.84, 95% CI 0.74-0.95), and adjusted Vasopressor Dose Equivalence (aOR 1.03, 95% CI 1.01-1.05) scores were independently associated with the development of arterial line-associated limb ischemia. A SOFA score of ≥17 at the time of ECMO cannulation had an 80% sensitivity and 87% specificity for predicting arterial line-related limb ischemia. CONCLUSIONS: Arterial line-related limb ischemia is much more common in ECMO patients than in the typical intensive care unit setting. The SOFA score may be useful in identifying which patients may be at risk for arterial line-related limb ischemia. As this was a single-center retrospective study, these results are inherently exploratory, and prospective multicenter studies are necessary to validate these results.