The use of whole blood capillary samples to measure 15 analytes for a home-collect biochemistry service during the SARS-CoV-2 pandemic: A proposed model from North West London Pathology

BACKGROUND

The COVID-19 pandemic has drastically changed the delivery of secondary care services. Self-collection of capillary blood at home can facilitate the monitoring of patients with chronic disease to support virtual clinics while mitigating the risk of SARS-CoV-2 infection and transmission.

OBJECTIVE

To investigate the comparability of whole blood capillary and plasma venous samples for 15 routinely used biochemical analytes and to develop and pilot a user-friendly home-collection kit to support virtual outpatient clinical services.

METHODS

To investigate the comparability of whole blood capillary and plasma venous samples for 15 routinely requested biochemical analytes, simultaneous samples of venous and capillary blood were collected in EDTA and lithium-heparin plasma separation tubes that were of 4-6 mL and 400-600 µL draw volume, respectively. Venous samples were analysed within 4 h of collection while capillary samples were kept at ambient temperature for three days until centrifugation and analysis. Analyte results that were comparable between the matrices were then piloted in a feasibility study in three outpatient clinical services.

RESULTS

HbA1c, lipid profile and liver function tests were considered comparable and piloted in the patient feasibility study. The home-collect kit demonstrated good patient usability.

CONCLUSION

Home collection of capillary blood could be a clinically-useful tool to deliver virtual care to patients with chronic disease.

Routine coagulation testing in Vacutainer® Citrate Plus tubes filled at minimum or optimal volume

Background Filling of citrate tubes with appropriate amount of blood is essential for obtaining reliable results of coagulation testing. This study aimed to verify whether results of routine coagulation tests are comparable when the new Becton Dickinson Vacutainer® Citrate Plus tubes are filled at minimum or optimal volume. Methods The study population consisted of 133 patients (40 on oral anticoagulant therapy), who had blood collected for routine coagulation testing. Two sequential Vacutainer® Citrate Plus tubes of the same type and lot were drawn. The first tube was collected after a butterfly needle was inserted into the vein, so that the air in the tubing was aspirated into the tube before blood (minimum fill volume), whilst the second was drawn at optimal fill volume. Experiments were repeated using 2.7-mL (n = 86) and 1.8-mL (n = 47) tubes. Results Prothrombin time (PT) and fibrinogen values were slightly but significantly decreased in tubes with minimum than in those with optimal fill volume. The activated partial thromboplastin time (APTT) was slightly prolonged in tubes with minimum than in those with optimal fill volume, but the difference was not statistically significant. An identical trend was noted in separate analyses for the 2.7-mL and 1.8-mL tubes. Spearman's correlations between the two fill volumes were always >0.94 and bias was always within the quality specifications. Conclusions Blood drawing into Vacutainer® Citrate Plus tubes at minimum fill volume does not clinically bias routine coagulation testing.

Small volume vacuum phlebotomy tubes: a controlled before-and-after study of a patient blood management initiative in an Australian adult intensive care unit

BACKGROUND

Patients admitted to intensive care units (ICUs) undergo multiple blood tests. Small volume vacuum phlebotomy tubes (SVTs) provide an important blood conservation measure. SVTs reduce summative blood loss and may reduce odds of transfusion. We aimed to determine whether low volume blood sampling using SVTs for routine diagnostic purposes translates to decreased fall in haemoglobin concentration, and examine downstream effects on anaemia and need for transfusion during ICU admission.

STUDY DESIGN AND METHODS

A single-centre, controlled before-and-after study, evaluating a unit-wide changeover from conventional volume vacuum phlebotomy tubes (CVTs) to SVTs on April 2015. All ICU patients admitted for > 48 hours during the 12 months before and after the intervention were included in multivariate and univariate analysis. Groups were stratified into short admissions (2-7 days) and long admissions (> 7 days).

RESULTS

A total of 318 patients were analysed. For short admissions, SVTs decreased fall in haemoglobin concentration (unstandardized coefficient, -6.7; P = 0.001) and episodes of severe anaemia (odds ratio, 0.37, P = 0.02). There were no changes to haemoglobin concentration in long admissions. No effects on need for transfusion were observed (short admissions, P = 0.05; long admissions, P = 0.11). SVTs reduced daily sampling volumes by 50% with no increase in laboratory error (short admissions, P = 0.61; long admissions, P = 0.98). A moderate correlation existed between blood draws and fall in haemoglobin concentration (short admissions, r = 0.5; long admissions, r = 0.32).

CONCLUSION

SVTs reduce sampling volume without increasing laboratory error. Follow-on effects include reduced fall in haemoglobin concentration and severe anaemia. These correlations are absent in long admissions.

Vein Pattern Locating Technology for Cannulation: A Review of the Low-Cost Vein Finder Prototypes Utilizing near Infrared (NIR) Light to Improve Peripheral Subcutaneous Vein Selection for Phlebotomy

One of the most common means for diagnosis is through medical laboratory testing, which primarily uses venous blood as a sample. This requires an invasive method by cannulation that needs proper vein selection. The use of a vein finder would help the phlebotomist to easily locate the vein, preventing possible pre-analytical error in the specimen collection and even more discomfort and pain to the patient. This paper is a review of the scientific publications on the different developed low-cost vein finder prototypes utilizing camera assisted near infrared (NIR) light technology. Methods: Electronic databases were searched online, these included PubMed (PMC), MEDLINE, Science Direct, ResearchGate, and Institute of Electrical and Electronics Engineers (IEEE) Xplore digital library. Specifically, publications with the terms vein finder prototype, NIR technology, vein detection, and infrared imaging were screened. In addition, reference lists were used to further review related publications. Results: Cannulation challenges medical practitioners because of the different factors that can be reduced by the utilization of a vein finder. A limited number of publications regarding the assessment of personnel performing cannulation were observed. Moreover, variations in methodology, number of patients, type of patients according to their demographics and materials used in the assessment of the developed prototypes were noted. Some studies were limited with regard to the actual human testing of the prototype. Conclusions: The development of a low-cost effective near infrared (NIR) vein finder remains in the phase of improvement. Since, it is being challenged by different human factors, increasing the number of parameters and participants/human for actual testing of the prototypes must also be taken into consideration for possible commercialization. Finally, it was noted that publications regarding the assessment of the performance of phlebotomists using vein finders were limited.

The Influence of a Blood Conserving Device on Anaemia in Intensive Care Patients

The contribution of iatrogenic blood loss through diagnostic testing to the anaemia of critical illness remains controversial. We measured the effect of an arterial line blood conservation device upon blood loss and anaemia in adult intensive care patients.

This randomized controlled trial of 160 patients in a major Intensive Care Unit (ICU) compared a blood conservation device (Venous Arterial Blood Management Protection Plus, VAMP Plus system, Baxter Healthcare) (VAMP group) to a standard arterial pressure line set attached to an arterial catheter (control group). The primary outcome measured was the change in haemoglobin concentration (Hb) during each patient's ICU admission and the volume of blood lost through diagnostic testing in ICU was also recorded.

Both groups of 80 patients were matched for age, gender, severity of illness (APACHE II), baseline Hb on entry and ICU length of stay. Both groups had a similar (median [range]) change in Hb during ICU admission (VAMP-7 [- 84 to+21] g/l; Control -4 [-67 to+40] g/l; P=0.33). The VAMP patients lost significantly less blood for diagnostic testing while in ICU (VAMP 63 [0 to 787] ml; Control 133 [7 to 1227] ml; P=0.001).

We conclude that the VAMP Plus system significantly reduced iatrogenic blood loss in critically ill patients, but this reduction did not affect the fall in Hb that accompanies critical illness.

Efficacy of the Buzzy® device for pain management of children during needle-related procedures: a systematic review protocol

BACKGROUND

Needle-related procedures are the most important source of pain in children in hospital setting. Unmanaged pain could result in short- and long-term physiological, psychological, and emotional consequences. Although the efficacy of numerous interventions has been evaluated, procedural pain management is often suboptimal in children undergoing needle-related procedures. The main objective of this systematic review is to examine the evidence for the efficacy of the Buzzy® device for needle-related procedural pain in children.

METHODS

An electronic search will be conducted in the following databases: CENTRAL, PubMed, MEDLINE, EMBASE, PsycInfo, and CINAHL. There will be no restriction regarding the language, date of publication, and publication status. Eligible studies will be randomized controlled trials using the Buzzy® device for pain management in children undergoing needle-related procedures. Selection of studies, data extraction and management, assessment of risk of bias and quality of evidence will be performed by two independent reviewers. A third researcher will be consulted in case of discrepancies. Depending on the availability and quality of the data as well as clinical and statistical heterogeneity, a meta-analysis will be performed. Otherwise, findings will be qualitatively reported.

DISCUSSION

This will be the first systematic review to examine the efficacy of the Buzzy® device on pain management of children during needle-related procedures. Results of this review will guide clinical practice and recommendations for further research to improve procedural pediatric pain management.

SYSTEMATIC REVIEW REGISTRATION

PROSPERO CRD42017076531.

[Medical practice assessment during the phlebotomy: clinical audit of blood sampling]

INTRODUCTION

Phlebotomy is taking a venous blood sample for a medical biology analysis .If the taking of a sample is poorly executed, the results for this sample may be inaccurate and mislead the clinician, or the inconvenience of the patient having to undergo a new levy. The three main problems associated with errors in the collection are: hemolysis, contamination and mislabelling. We conduct clinical audit to evaluate compliance of activities in relation to the recommendations. Our objective was to determine the compliance rate of the different steps of the phlebotomy procedure and propose corrective actions.

METHODS

it is an observational study which follows a forward-looking approach based on direct observation of blood collection procedures in 2015.

RESULTS

330 acts of phlebotomy were audited in 11 services. The overall compliance rate phlebotomy was 57.7%. The overall compliance rate ''patient prescribing and preparation "was 94.4%; "equipment preparation" was 85.3%. There was a lack of tourniquets, holders and hydro-alcoholic solutions. The overall compliance rate "collection procedure" was 45.1%, the overall compliance rate for hand hygiene is low (28%), wearing gloves (20%) and the use of antiseptics (44.4%). The overall compliance rate "sample identification"quot; was 61.3% (tube labeling (45.7%) and compliance of the laboratory worksheet (76.9%). the overall compliance rate "Transport" was 49.4%. There was a lack of bag or holders for transport.

CONCLUSION

The results obtained allowed to propose an improvement plan to improve this practice. In fact, the ultimate purpuse of medical practice assessment is to improve the quality of care.

Effects of a new device to guide venous puncture in elderly critically ill patients: results of a pilot randomized study

BACKGROUND

Novel devices based on the emission of near-infrared electromagnetic radiation (NIR) have been developed to minimize venous puncture failures. These instruments produce an "augmented reality" image, in which subcutaneous veins are depicted on a LCD display. We compared the new technique with standard venipuncture in a population of elderly patients.

METHODS

Patients admitted in Intensive Care Unit were randomized to standard or to NIR assisted procedure.

RESULTS

In the 103 enrolled patients (age 74 ± 12 years; standard venipuncture-N = 56; NIR-N = 47), no differences were found in procedure length, number of attempts, and referred pain. With NIR there was a lower incidence of hematomas and fewer anxiety and depressive symptoms.

CONCLUSIONS

The use of the novel NIR-based device is safer and more psychologically tolerable, and it is not associated to an increase of procedure length or number of attempts.

Optimization of left adrenal vein sampling in primary aldosteronism: Coping with asymmetrical cortisol secretion

We evaluated the influence of catheter sampling position and size on left adrenal venous sampling (AVS) in patients with primary aldosteronism (PA) and analyzed their relationship to cortisol secretion. This retrospective study included 111 patients with a diagnosis of primary aldosteronism who underwent tetracosactide-stimulated AVS. Left AVS was obtained from two catheter positions - the central adrenal vein (CAV) and the common trunk. For common trunk sampling, 5-French catheters were used in 51 patients, and microcatheters were used in 60 patients. Autonomous cortisol secretion was evaluated with a low-dose dexamethasone suppression test in 87 patients. The adrenal/inferior vena cava cortisol concentration ratio [selectivity index (SI)] was significantly lower in samples from the left common trunk than those of the left CAV and right adrenal veins, but this difference was reduced when a microcatheter was used for common trunk sampling. Sample dilution in the common trunk of the left adrenal vein can be decreased by limiting sampling speed with the use of a microcatheter. Meanwhile, there was no significant difference in SI between the left CAV and right adrenal veins. Laterality, determined according to aldosterone/cortisol ratio (A/C ratio) based criteria, showed good reproducibility regardless of sampling position, unlike the absolute aldosterone value based criteria. However, in 11 cases with autonomous cortisol co-secretion, the cortisol hypersecreting side tended to be underestimated when using A/C ratio based criteria. Left CAV sampling enables symmetrical sampling, and may be essential when using absolute aldosterone value based criteria in cases where symmetrical cortisol secretion is uncertain.

Preanalytical external quality assessment of the Croatian Society of Medical Biochemistry and Laboratory Medicine and CROQALM: finding undetected weak spots

INTRODUCTION

The aim of this paper is to present results of first two years of preanalytical external quality assessment (EQA) in Croatia.

MATERIALS AND METHODS

This paper summarizes results from 6 rounds of preanalytical EQA during 2014-2016 in 161-175 Croatian laboratories (number ranged between cycles). EQA was designed as an online survey of the compliance with National recommendations for phlebotomy (NRP). Forty-seven questions in 5 categories are analyzed (materials and equipment, patient identification, patient preparation, sampling and storage). Additionally, preanalytical cases are presented. Overall performance scores (Question score (Qscore) for compliance with NRP and Case score (Cscore) for preanalytical cases) are calculated for each question/case as a proportion of laboratories with satisfactory procedure (x 100). Qscores and Cscores ≥ 70 were classified as acceptable (maximal score = 100).

RESULTS

In investigation of compliance with NRP, acceptable Qscores were obtained for 34/47 questions. The lowest scores were observed for the availability of sterile disposable tourniquets (Qscore = 15) and safe-sharp needles (Qscore = 34), obtaining patients address as an identifier (Qscore = 21), using glycolysis inhibitor tubes for glucose concentration measurement (Qscore = 21) and verification of manufacturers declarations on temperature and time of storage (Qscore = 31). There was no statistically significant difference in overall Qscore according to different categories of phlebotomy procedures (P = 0.284). The results of preanalytical cases showed acceptable Cscore values for all cases (89-96).

CONCLUSION

First two years of preanalytical EQA showed good compliance with the NRP and excellent expertise in resolving complex preanalytical issues. Major critical spots are lack of availability of safe-sharp needles, disposable tourniquets and glucose inhibitor tubes.

3D Near Infrared and Ultrasound Imaging of Peripheral Blood Vessels for Real-Time Localization and Needle Guidance

This paper presents a portable imaging device designed to detect peripheral blood vessels for cannula insertion that are otherwise difficult to visualize beneath the skin. The device combines near infrared stereo vision, ultrasound, and real-time image analysis to map the 3D structure of subcutaneous vessels. We show that the device can identify adult forearm vessels and be used to guide manual insertions in tissue phantoms with increased first-stick accuracy compared to unassisted cannulation. We also demonstrate that the system may be coupled with a robotic manipulator to perform automated, image-guided venipuncture.

A Randomized Clinical Trial of Jet-Injected Lidocaine to Reduce Venipuncture Pain for Young Children

STUDY OBJECTIVE

The J-Tip (National Medical Products Inc, Irvine, CA) uses air instead of a needle to push lidocaine into the skin. To our knowledge, no studies have investigated its use for venipuncture in young children. We determine whether the J-Tip decreased venipuncture pain in young children compared with vapocoolant spray.

METHODS

Children aged 1 to 6 years were randomized into 3 groups: intervention (J-Tip), control (vapocoolant spray), and sham (vapocoolant spray and pop of an empty J-Tip). The procedure was videotaped and scored with the Face, Legs, Activity, Cry and Consolability (FLACC) tool at 3 points; baseline, before approach; device, at J-Tip deployment; and at venipuncture. The FLACC tool was scored 0 (none) to 10 (severe). Comparisons of pain scores over time were made with the generalized estimating equation. Venipuncture success and adverse effects were assessed and compared with χ(2).

RESULTS

Two hundred five children enrolled: intervention 96, control 53, and sham 56. There were no between-group differences in baseline characteristics. There was no mean change in pain scores from device to venipuncture in the intervention group (0.26; 95% confidence interval [CI] -0.31 to 0.82), but there was an increase in pain in the control (2.82; 95% CI 1.91 to 3.74) and sham (1.68; 95% CI 0.83 to 2.52) groups. This change was greater for the control and sham compared to the intervention group. There was no difference in venipuncture success between groups. No severe adverse events occurred. Minor adverse events were the same between groups.

CONCLUSION

Use of the J-Tip for children aged 1 to 6 years reduced venipuncture pain compared with vapocoolant spray or sham treatment.

Twenty-five million liters of blood into the sewer

Laboratory medicine has evolved tremendously but not so much to the individual patient's benefit as far as the volume of blood samples is concerned. It can be calculated that with the current collection methods and the small amounts of blood or serum required by modern laboratory analyzers in the Western world alone each 25 million liter of patients' blood is thrown into waste containers. That is four times more than the total volume of blood that is transfused each year. And this is not a trivial issue, as studies show that many patients develop 'hospital acquired anemia' due to blood collection and this is associated with an adverse outcome. It is time that collection methods for blood samples are adapted to the much smaller volumes that are required by new generation laboratory analyzers, in particular for vulnerable groups, such as hematology or oncology patients, critically ill patients, or children.

Demonstration of compatibility of multiple arterial blood gas syringes with current multi-parameter analyzers

OBJECTIVE

Since there is a lack of current evidence to support the compatibility of the most commonly used arterial blood gas syringes with the latest multi-parameter analyzers, the objective of this study was to assess the agreement of analyte values between three heparinized arterial blood gas syringes using three different analyzers.

METHODS

Venous blood from 25 healthy volunteers was drawn into the study syringes (BD Drihep A-Line, PICO50, and Portex Line Draw Plus) by four clinician volunteers in a random order (441 total) and immediately (<15 minutes) analyzed (ABL800 FLEX, RAPIDPoint 500, i-STAT System) in a randomized order. The Bland-Altman method was used to assess agreement of analyte values between the syringes for each analyzer. The results by analyte and analyzer were compared across syringes using one-way ANOVA, and Tukey's approach was used to identify statistically significant differences between pairs of syringes.

RESULTS

Comparison of the syringes' mean differences and standard deviations showed close agreement for all three analyzers. There were no statistically significant differences between syringes in 14 of the analytes for any of the analyzers (p > 0.05). For RAPIDPoint and i-STAT, the Ca(2+) value was significantly less for A-Line than for the other syringes. The value for Na(+) was significantly greater for the PICO50 than the A-Line and Line Draw syringes with the i-STAT. Both results were within two standard deviations of the mean of the other two syringes and are not considered clinically significant; however, comparisons were not made between the values from the different analyzers.

CONCLUSIONS

Dry-balanced lithium heparin ABG syringes used for blood draws should provide reliable results, regardless of syringe type, provided that the clinicians use proper pre-analytical techniques.

Towards a low-cost mobile subcutaneous vein detection solution using near-infrared spectroscopy

Excessive venipunctures are both time- and resource-consuming events, which cause anxiety, pain, and distress in patients, or can lead to severe harmful injuries. We propose a low-cost mobile health solution for subcutaneous vein detection using near-infrared spectroscopy, along with an assessment of the current state of the art in this field. The first objective of this study was to get a deeper overview of the research topic, through the initial team discussions and a detailed literature review (using both academic and grey literature). The second objective, that is, identifying the commercial systems employing near-infrared spectroscopy, was conducted using the PubMed database. The goal of the third objective was to identify and evaluate (using the IEEE Xplore database) the research efforts in the field of low-cost near-infrared imaging in general, as a basis for the conceptual model of the upcoming prototype. Although the reviewed commercial devices have demonstrated usefulness and value for peripheral veins visualization, other evaluated clinical outcomes are less conclusive. Previous studies regarding low-cost near-infrared systems demonstrated the general feasibility of developing cost-effective vein detection systems; however, their limitations are restricting their applicability to clinical practice. Finally, based on the current findings, we outline the future research direction.

Ergonomic procedure for heel sticks and shots in Kangaroo Care (skin-to-skin) position

Kangaroo Care (KC) has been recommended as a pain-reducing strategy in neonates; however, KC has not been widely used to minimize procedural pain caused in part by nurses'/phlebotomists' discomfort when positioning themselves and the infant for blood drawing and injections. Therefore, an ergonomically designed setup incorporating the use of KC was introduced into clinical practice to facilitate blood draws and injections. The step-by-step procedure used for heel sticks and injections is presented in this manuscript. After implementing the ergonomic step-by-step protocol, complaints of discomfort by nurses and phlebotomists ceased, and an additional benefit was that infant pain responses were significantly reduced.

Clarification of the characteristics of needle-tip movement during vacuum venipuncture to improve safety

BACKGROUND

Complications resulting from venipuncture include vein and nerve damage, hematoma, and neuropathic pain. Although the basic procedures are understood, few analyses of actual data exist. It is important to improve the safety standards of this technique during venipuncture. This study aimed to obtain data on actual needle movement during vacuum venipuncture in order to develop appropriate educational procedures.

METHODS

Six experienced nurses were recruited to collect blood samples from 64 subjects. These procedures were recorded using a digital camera. Software was then used to track and analyze motion without the use of a marker in order to maintain the sterility of the needle. Movement along the X- and Y-axes during blood sampling was examined.

RESULTS

Approximately 2.5 cm of the needle was inserted into the body, of which 6 mm resulted from advancing or moving the needle following puncture. The mean calculated puncture angle was 15.2°. Given the hazards posed by attaching and removing the blood collection tube, as well as by manipulating the needle to fix its position, the needle became unstable whether it was fixed or not fixed.

CONCLUSION

This study examined venipuncture procedures and showed that the method was influenced by increased needle movement. Focusing on skills for puncturing the skin, inserting the needle into the vein, and changing hands while being conscious of needle-tip stability may be essential for improving the safety of venipuncture.

Getting the basics right: delays in phlebotomy and intravenous cannulation: a survey of foundation year 1 doctors

Junior doctors frequently experience delays in routine ward-based procedures. There is little published data on this subject, but it is clear that such delays can have implications in terms of costs, efficiency, length of patient stay, team working and patient safety and experience. We formulated an anonymous online survey to quantify the experiences of foundation year 1 (FY1) doctors with respect to phlebotomy services and intravenous (IV) cannulation. We gathered data on equipment availability, time taken to carry out these tasks and the factors thought to contribute to delays. The results were compared to clinically relevant standards. Between April and August 2012, 199 responses were received. For IV cannulation, 21% of doctors reported equipment availability as 'very good', but only 3% said that they were able to find all of the pieces of equipment they needed close to each other ('essentially in the same place'). Similar results were obtained for phlebotomy. Nevertheless, there appears to be significant room for improvement and we offer recommendations to address delays.

A qualitative study of phlebotomy device selection

Limited research exists comparing Vacutainer versus butterfly phlebotomy devices. The purpose of this study was to examine decision processes staff use when choosing a device. A qualitative, purposive sampling was used and determined a gap between correct device use and reported practice. Applied findings can enhance employee safety.

Use of separate venipunctures for IV access and laboratory studies decreases hemolysis rates

Emergency department (ED) patients routinely undergo placement of a saline lock device (SLD) with the aspiration of blood for laboratory testing. Drawing blood through a SLD may result in hemolysis of sample, repeated venipuncture and increased ED length of stay (LOS). The objective of this study was to examine if separate venipunctures for intravenous (IV) access and laboratory studies decrease the rate of hemolysis and ED LOS. The study was conducted at an urban university level 1 trauma center with an ED volume of 55,000. We compared the rate of hemolysis and ED LOS before and after mandating the use of separate venipunctures for IV access and laboratory studies over 1 month. Venipuncture was performed utilizing either a 21 ga needle or an IV catheter (BD Insight Autoguard) with a needless vacutainer. The incidence of hemolysis was calculated and a Student's t test was used to compare groups. The potassium sample redraw and processing time was observed. Blood was aspirated from 315 patients using the SLD. A baseline hemolysis rate of 23.0% (16.7-29.1) was obtained, corrected to 6.7% after factoring a 29.2% redraw rate for critical potassium levels. In the following month, 2,564 samples were obtained using the butterfly needle with a hemolysis rate of 6.6% (5.5-7.5), corrected to 2.0% after applying the 29.2% redraw rate. Avoiding hemolysis, we saved 4.7% of our patients' 56 min of ED stay, and avoided 185 retests over the month. In conclusion, venipuncture from a butterfly needle decreases the rate of hemolysis and may decrease the overall ED LOS.

[Viewing veins with AccuVein AV300]

In spite of the major advances which have occurred in medicine and biotechnology over these last years, regarding intravenous therapy the greatest advances have occurred, on the one hand, in bio-compatible and throw away catheters and, on the other hand, in security devices which avoid accidental punctures. Advances to locate veins have been very limited, having been developed on occasion by devices which are not easily transported and which require fungible material when they make contact with a patient's skin. The AccuVein AV300 device is a portable manual use instrument which enables nurses to locate certain peripheral veins. This device does not substitute a nurse's traditional skill in locating veins by visual or feeling means, but rather this device supplements their skills and enhances them. This device is lightweight, intuitive, and does not require previous training for its use and hygiene since it never enters into contact with a patient's skin as it emits an infrared light on the skin which reflects veins drawing them on the surface of the skin.

Plasma-generating glucose monitor accuracy demonstrated in an animal model

INTRODUCTION

Four randomized controlled trials have compared mortality and morbidity of tight glycemic control versus conventional glucose for intensive care unit (ICU) patients. Two trials showed a positive outcome. However, one single-center trial and a large multicenter trial had negative results. The positive trials used accurate portable lab analyzers. The negative trial allowed the use of meters. The portable analyzer measures in filtered plasma, minimizing the interference effects. OptiScan Biomedical Corporation is developing a continuous glucose monitor using centrifuged plasma and mid-infrared spectroscopy for use in ICU medicine. The OptiScanner draws approximately 0.1 ml of blood every 15 min and creates a centrifuged plasma sample. Internal quality control minimizes sample preparation error. Interference adjustment using this technique has been presented at the Society of Critical Care Medicine in separate studies since 2006.

METHOD

A good laboratory practice study was conducted on three Yorkshire pigs using a central venous catheter over 6 h while performing a glucose challenge. Matching Yellow Springs Instrument glucose readings were obtained.

RESULTS

Some 95.7% of the predicted values were in the Clarke Error Grid A zone and 4.3% in the B zone. Of those in the B zone, all were within 3.3% of the A zone boundaries. The coefficient of determination (R(2)) was 0.993. The coefficient of variance was 5.02%. Animal necropsy and blood panels demonstrated safety.

CONCLUSION

The OptiScanner investigational device performed safely and accurately in an animal model. Human studies using the device will begin soon.

Evaluation of a blood conservation strategy in the intensive care unit: a prospective, randomised study

OBJECTIVE AND METHODS

Anemia is a common problem in the ICU population. Most patients are anemic at admission, their hemoglobin concentrations declining further thereafter. The aim of the present study was to evaluate the effect of a combination strategy, involving closed arterial blood gas sampling and the use of pediatric vials for phlebotomy (Group A), on the sampling-induced blood loss and the rate of decline in hemoglobin in adult ICU patients. Combination (Group A) was compared to the current standard technique of arterial line sampling and adult vial phlebotomy (Group B) in a prospective, randomised, ethically-approved trial for the first 72 hours of their ICU stay. Peri-operative, oncology, coagulopathic and uremic patients were excluded. All other ICU patients with arterial cannulae and predicted to stay beyond 3 days, were enrolled.

RESULTS

39 patients entered the study, 20 in Group A, and 19 in Group B. Data collection was complete for all. There was a statistically significant difference in sampling-induced blood loss between the groups over the first 72 hours of treatment (mean +/- standard deviation: 15.16 +/- 5.3 ml Group A vs 45.11 +/- 14 ml Group B, p<0.001). There was a smaller decline in mean hemoglobin level, which was not statistically significant (0.79 +/- 0.6 g/dL vs 1.30 +/- 1.13, p = 0.09).

CONCLUSIONS

Overall, this strategy reduced measurable blood losses from phlebotomy. In larger trials it might also preserve hemoglobin levels.

Observational study to determine factors associated with blood sample haemolysis in the emergency department

INTRODUCTION

Haemolysis of blood samples is a common problem encountered in the Emergency department (ED). It leads to inaccurate blood results and has cost implications as blood samples very often have to be retaken. The purpose of our study was to determine which factors in blood sampling were associated with higher rates of haemolysis.

MATERIALS AND METHODS

An observational convenience sample of all patients presenting to the ED requiring blood urea and electrolyte (UE) analysis were eligible for our study. Questionnaires were distributed to the doctors and nurses conducting blood sampling to determine the method used and outcome data were collected after the samples were processed.

RESULTS

Out of 227 UE samples analysed, 45 (19.8%) were haemolysed. Various factors, including method (IV cannulation or venepuncture), system (syringe or vacutainer), operator, rate of blood flow, difficulty of cannulation/venepuncture and source of blood (arterial or venous), were analysed, but their effects on haemolysis were not statistically significant (P >0.05). However, the use of the vacutainer system was associated with the highest rates of haemolysis [adjusted odds ratio (OR), 6.0; 95% confidence interval (CI), 2.3 to 15.1].

CONCLUSION

We found blood sampling with the vacutainer system to have increased rates of haemolysis. This could potentially change attitudes towards equipment used for blood sampling in the ED.

Fainting and hemolysis during blood sampling in youngsters: Prevalence study

OBJECTIVE

To assess the incidence of fainting and hemolysis in taking blood samples from adolescents in a school setting.

DESIGN

A cross-sectional school-based survey. All blood samples and data were collected during September and October 2005.

SUBJECTS

A community sample of 869 youngsters attending third grade secondary education in 14 secondary schools in the Flemish province of Antwerp, Belgium (mean age: 17.3 years, +/-1.2 years).

MEASUREMENTS

Fasting blood samples were obtained on-site for measurement of levels of glucose, high density lipoprotein cholesterol and triglycerides. The incidence of fainting and hemolysis was assessed.

RESULTS

In 60% of the total sample a blood sample was taken, 15% refused. In the remaining 25%, taking a blood sample was not possible due to problems in drawing blood from the vein (4%) or not fasting (21%). The incidence of fainting was 2.5%. Hemolysis occurred in 2.4% of the blood samples.

CONCLUSION

When taking blood samples in this age group, there seems to be a great willingness to participate. Precaution should be taken though when taking blood samples in youngsters. In this study, about 1 in 40 students fainted. When blood samples are taken on-site and transported to a laboratory, an incidence of hemolysis of 2.4% should be taken into account.

Evaluation of the use of subcutaneous implantable vascular access ports in feline blood donors

OBJECTIVE

To compare the ease and effects of collecting blood from cats by use of subcutaneous totally implantable vascular access ports (VAPs) with collection via conventional jugular phlebotomy.

DESIGN

Prospective randomized experimental study.

ANIMALS

8 healthy cats.

PROCEDURES

Cats in the port group (n = 4) underwent monthly blood donation by use of VAPs and manual restraint, and cats in the nonport group (4) underwent monthly blood donation by use of conventional jugular phlebotomy and sedation, for 6 months.

RESULTS

Postsurgical VAP-related complications developed in 3 cats and included port erosion (n = 1), disconnection of the port from the catheter (1), and seroma formation (1). Blood was successfully collected 24 of 24 and 20 of 20 times in the nonport and port groups, respectively. Results of bacterial culture of blood were negative in 22 of 24 and 15 of 20 nonport and port collections, respectively. No differences in RBC morphology were observed between groups. Mean blood collection and total donation times were significantly longer for the nonport group. Collection time was more variable in the nonport group, and cats were less tolerant of handling during venipuncture, compared with cats in the port group. Blood collection required a mean of 2.4 persons for the nonport group and 2.1 persons for the port group.

CONCLUSIONS AND CLINICAL RELEVANCE

Positive results for blood collections via VAPs were increased donor acceptance, decreased number of personnel required, and decreased collection time. Drawbacks included contamination of blood products and port-related complications.

An evaluation of automated blood collection mixers

BACKGROUND AND OBJECTIVES

We investigated the mixing capacity of two whole blood (WB) collection mixers.

MATERIALS AND METHODS

WB was simulated by using a 25% glycerol solution warmed to 35 degrees C. Citrate-phosphate-dextrose (CPD) anticoagulant of a collection system was stained with toluidine blue, and simulated WB was added at 30, 60 or 90 ml/min, respectively (n = 3 per flow speed). The optical density (OD) of 10-ml fractions was measured, and results are expressed as percentage of a well-mixed '100%-sample'.

RESULTS

CompoGuard showed adequate mixing at all three flow speeds (average ODs 96-103%). HemoLight showed good mixing at 60 and 90 ml/min (ODs from 97 to 101%). At 30 ml/min, mixing appeared suboptimal, but still conformed to our requirements with ODs from 96% to 104%.

CONCLUSION

Both mixers give sufficient mixing of whole blood with anticoagulant.

Highly conservative phlebotomy in adult intensive care--a prospective randomized controlled trial

Anaemia in critically ill patients is common and phlebotomy associated blood loss may contribute towards this anaemia. The aims of this study were twofold. Firstly, a survey was conducted to provide a summary of current phlebotomy practices within Australian intensive care units. A standardized telephone survey was aimed at Australian intensive care units registered with Australia and New Zealand Intensive Care Society (ANZICS) and questions regarding phlebotomy procedures directed at nursing staff. Secondly, a prospective randomized controlled trial aimed to assess the impact of a highly conservative phlebotomy procedure on haemoglobin concentration in intensive care patients. Patients admitted to our own intensive care unit were randomized using a sealed envelope technique to either a highly conservative phlebotomy group, or standardized controls. Blood was taken according to strict protocols and recorded along with haemoglobin concentration daily. The survey demonstrated that 16% of Australian units return deadspace volumes from in-line arterial sets and no unit routinely used paediatric-sized blood collection tubes. Using our highly conservative protocol, median phlebotomy-associated blood loss was reduced by over 80% (40 ml vs 8 ml P<0.001). Mean haemoglobin fell from 13.7 g/dl to 11.7 g/dl in controls (P=0.002) and from 12.7 g/dl to 11.5 g/dl (P=0.074) in our study group. We conclude that highly conservative phlebotomy is feasible in a critical care unit and is associated with a reduction in blood loss.

[A novel method for the self-collection of blood, "thenar lancing phlebotomy" and investigation of its accuracy]

"Thenar lancing phlebotomy" is a novel method for the self-collection of blood using a special phlebotomy device for the thenar and a self-collection blood kit. The thenar is punctured with a special lancet, the vein is subjected to automatic avascularization at the wrist and at the same time, a small centrifuge tube, attached to the suction cylinder of the device, is applied to the puncture and the blood is collected by suction. The small centrifuge tube containing the whole blood is centrifuged with a portable centrifugal separator to obtain plasma. In comparison with conventional finger prick phlebotomy, there is less pain and sufficient blood may be obtained. To investigate the accuracy of the method, we collected blood from the antecubital vein of 140 subjects and thenar lancing phlebotomy was simultaneously carried out on the same 140 subjects. The results of many blood tests currently included in medical check-ups were almost identical in the blood samples of both groups, suggesting that this method can be utilized in medical check-ups using self-collected blood sampies.

Femoral phlebotomy: the vacuum tube method is preferable over needle syringe

A syringe needle (SN) is commonly used to obtain blood specimens from the femoral vein. The vacuum tube (VT) method avoids the needle stick potential of the SN technique during transfer of blood from the syringe to the collection tubes. We compared the perceived safety, patient pain, and efficacy of SN and VT for femoral phlebotomy in a prospective trial. Of 64 patients entered, 38 (59%) had the VT technique and 26 (41%) had the SN technique. There was no significant difference in the success rate between VT and SN (100% vs. 95%, respectively). The VT method was somewhat faster than the SN method (104 +/- 109 vs. 181 +/- 149 s, respectively, p = 0.06). Complications were infrequent and not different between the groups. The mean patient pain score +/- SD on a 10-cm visual analog scale for the VT and SN techniques were 2.6 +/- 2.2 and 3.7 +/- 2.7, respectively (p < 0.001). Physicians subjectively rated the safety of the procedure higher for the VT method than for the SN method. Medical personnel should consider use of the VT method instead of the traditional SN technique for femoral phlebotomy.

Reducing the potential for phlebotomy tourniquets to act as a reservoir for meticillin-resistant Staphylococcus aureus

The contamination rate of phlebotomy tourniquets with meticillin-resistant Staphylococcus aureus (MRSA) was assessed, and it was determined whether this could be reduced by changes in practice or by the use of a physical barrier. Initially, the tourniquets of both preregistration house officers and phlebotomists were investigated, but as phlebotomists reported significantly more venepunctures daily, the trial continued solely with phlebotomists. Each day, the phlebotomists were supplied with a fresh sterile tourniquet, and after use, the tourniquets were swabbed and cultured. The rate of contamination with MRSA was 32 of 131 (25%) tourniquets. An audit of hand hygiene practice was undertaken and revealed that phlebotomists were performing hand decontamination inadequately between patients and wore wristwatches while working. Education comprising standard infection control methods to encourage good practice was given. After this, a polythene strip was used as a barrier by half of the phlebotomists during all venepunctures. Tourniquets were cultured and replaced daily as before. During this stage of the trial, the rates of contamination were 1 of 46 tourniquets (using a polythene strip) and 1 of 42 tourniquets (without using a polythene strip). In conclusion, phlebotomy tourniquets may be potential vectors for transferring bacteria, including MRSA. Contamination rates, and hence potential risk, can be reduced if hand decontamination is performed. This suggests that contamination of tourniquets is via phlebotomists' hands, not directly from patients' skin. Hand hygiene should be regarded as the most important method by which the spread of organisms can be reduced.

Venepuncture: best practice

Venepuncture is the introduction of a needle into a vein to obtain a blood sample for haematological, biochemical or bacteriological analysis. It is the most common invasive procedure undertaken in hospital. This article provides guidance on the theory and practice of venepuncture.

Factors Affecting Hemolysis Rates in Blood Samples Drawn From Newly Placed IV Sites in the Emergency Department

INTRODUCTION

To decrease the number of hemolyzed samples in the emergency department, performance improvement activities were implemented, including phlebotomy classes for staff, evaluation of blood draw equipment, and a study to evaluate factors attributed to hemolysis of blood samples when drawn at the time a new intravenous catheter is inserted.

METHODS

In a study with an observational design conducted in June and July 2004, researchers examined the cases of 100 randomly chosen patients who had blood drawn through newly placed peripheral intravenous access.

RESULTS

In this study, the blood draw collection factors with the highest hemolysis rates included blood samples drawn between 12:00 am to 5:59 am; samples drawn by patient care technicians; right-hand site; 22-gauge intravenous catheters; syringe draws; blue tubes; 6.0 mL tubes; difficulty drawing blood; 2 tries for intravenous placement; resistance when aspirating blood using a syringe; and respiratory discharge diagnoses. Statistically significant (P < .05) blood draw factors included intravenous placement sites of right hand/forearm and antecubital; intravenous catheter size 22 gauge; blood drawing categorized as difficult; number of tries for intravenous placement; blood tube size 1.8 mL; and discharge diagnoses of respiratory, gastrointestinal, reproductive, dermatologic, and endocrine.

DISCUSSION

Clinically meaningful factors associated with hemolysis rates included the use of a 22-gauge intravenous catheter size, which resulted in a hemolysis rate of 60%; in addition, intravenous placement sites on the right side had statistically significant higher hemolysis rates than the left side, a finding that merits further research. As a result of the study we modified our standard operating procedure to discontinue the use of a 22-gauge or smaller intravenous catheter in adults. If required for small vein sticks, the use of a straight needle stick to obtain blood samples should be considered. The results of this study underscore the importance of education and training and the consideration for regular competency testing for staff with phlebotomy responsibilities.

Comparison of contamination rates of catheter-drawn and peripheral blood cultures

The aim of this study was to assess the sensitivity and specificity of catheter-drawn and peripheral blood cultures. Paired blood culture samples collected over a 44-month period from a 280 bed Brisbane metropolitan hospital were analysed, using standard clinical and microbiological criteria, to determine whether blood culture isolates represented true bacteraemias or contamination. Catheter-collected cultures had a specificity of 85% compared with 97% for peripheral cultures. In only two instances (0.2%) was the diagnosis of clinically significant bacteraemia made on the basis of catheter culture alone. This study concluded that catheter-collected samples are not a good test for true bacteraemia, and that peripheral cultures are more reliable when the results of the paired cultures are discordant.

Longitudinal comparison of preterm pain responses to repeated heelsticks

BACKGROUND

Preterm infants receive repeated heelsticks over their hospitalization, yet contradictions exist regarding the influence of prior heelsticks, prior painful procedures, and severity of illness on assessment of the pain responses.

PURPOSES

Compare pain responses to repeated heelsticks in infants of varying gestational age groups, and determine the influence of number of prior heelsticks, total number of prior painful procedures, and severity of illness on pain responses over time.

DESIGN AND METHODS

The descriptive longitudinal design utilized a convenience sample of 81 preterm infants from a Midwestern Level III newborn intensive care unit (NICU).

RESULTS

Significant differences in Preterm Infant Pain Profile (PIPP) scores were found between age groups. Both the severity of illness and the total number of prior painful procedures had a significant influence on pain scores.

CONCLUSIONS

Nurses' use of developmental care and the QuickHeel device may result in lower pain scores. Higher severity of illness and number of prior heelsticks may lower pain scores.