Using Failure Mode and Effects Analysis in Improving Nursing Blood Sampling at an International Specialized Cancer Center.

BACKGROUND: The process of blood sampling is considered one of the primary and most common nursing invasive procedures carried out daily. Any failure at any point could have a severe negative impact on patient outcomes. PURPOSE: This project aimed to assess and improve the nursing blood sampling process in a specialized cancer center using failure mode and effect analysis (FMEA). METHODS: An observational analytical design of the nursing blood sampling process using FMEA was conducted in King Hussein Cancer Center in Amman, Jordan. Seven steps were conducted, including a review of the blood sampling process, brainstorming potential failures, listing potential effects of each failure mode, assigning a severity rating for each potential effect, assigning a frequency/occurrence rating for each failure mode, assigning a detection rating scale for each failure mode, and calculating the Risk Priority Number (RPN) for each effect. RESULTS: Eight (out of 28) main critical failure modes with more than 200 RPN were identified in the blood sampling process. Accordingly, five themes were developed to guide the corrective actions. These themes included: process and responsibility modifications, resource and information technology utilization, patients and family engagement, safety culture, and education and training after implementation of the corrective actions. This resulted in a 58 % reduction in the RPN of major failure modes. CONCLUSION: Many factors lead to blood sampling errors. A critical focus should be conducted on the preparation phase due to the possible errors that may occur. Proper identification of patients and blood sample tests are the keys to a significant decrease in blood sampling errors.
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Applying Queuing Theory and Mixed Integer Programming to Blood Center Nursing Schedules of a Large Hospital in China.

Blood centers in large hospitals in China are facing serious problems, including complex patient queues and inflexible nursing schedules. This study is aimed at developing a flexible scheduling method for blood center nurses. By systematically analyzing the constraints that affect scheduling, a flexible scheduling model is established based on queuing theory and mixed integer programming. This combined model can reasonably determine the number of nurses required during a given working period and flexibly arrange nursing schedules while ensuring sufficient rest periods for individual nurses. Results of numerical studies conducted using data from a large hospital in China show a significant improvement in patient waiting time performance metrics over the hospital's current practice. In addition, the nurses' workloads and rest periods are well balanced, indicating that the proposed method can effectively and flexibly arrange nursing shifts in blood centers.

Blood sampling during nurse triage reduces patient length of stay in the emergency department: A propensity score-weighted, population-based study.

BACKGROUND: Increases in patients' length of stay (LOS) in the emergency department (ED) have led to overcrowding. OBJECTIVES: In this study, the implementation of blood sampling during triage in lower priority level patients was assessed as a possible means to reduce LOS. METHODS: A retrospective study was performed from January 2018 to January 2019. Lower priority level patients who required blood sampling for further diagnosis were considered. Patients who underwent blood sampling during triage evaluation were compared with those who underwent blood sampling after a physician's initial evaluation. RESULTS: During the study period, 15,596 patients were enrolled. LOS was shorter in patients who underwent triage blood sampling, presenting a median value of 154 min in comparison with the 172 min recorded in the control group (p < 0.001). Using a propensity score-matching to control the two groups' differences, LOS remained lower in the triage-sampling group (151 vs. 175 min; p < 0.001). In the adjusted multivariate model, triage blood sampling was found to be an independent factor for a decrease in the LOS, with standardized coefficient ß = 0.857 (0.822-0.894; p < 0.001). CONCLUSIONS: Performing blood sampling during nurse triage can decrease LOS in ED and also reduce ED permanence after a physician's initial evaluation.

Identification of the self-confidence and self-efficacy levels of student nurses when performing blood drawing for the first time on their peers.

BACKGROUND: Blood sampling is frequently used in health to evaluate diagnosis and treatments. The first blood drawing is most important skill for nursing students. Nursing students gain these skills during their first years of education. OBJECTIVE: To identify the self-confidence and self-efficacy levels of first year nursing students when performing taking blood on their peers for the first time. METHODS: The sample (n= 70) of this descriptive and cross-sectional research comprised first year nursing students. The research was conducted in two stages; theoretical training and laboratory work and students' first taking blood on their peers. A Student Information Form, Blood drawing Skill Practice Evaluation Control Form, Self-Confidence Scale, and General Self-Efficacy Scale were used for data collection. Percentage calculations and the Mann-Whitney U test were used for data analysis. RESULTS: The total mean score of the students' self-confidence was 130.09 ± 15.94 (Min = 91, Max = 157), and total mean score of self-efficacy was identified as 31.71 ± 3.92 (Min = 20, Max = 39). No statistically significant difference was detected between the students' sex and high school type regarding self-confidence and self-efficacy total mean scores (p> 0.05). CONCLUSIONS: It was observed that students' self-confidence and self-efficacy levels were high when performing taking blood on their peers for the first time.

[Reducing Blood Culture Contamination Rates in the Emergency Department].

BACKGROUND: Rate of contamination is a well-known indicator of quality of care in the emergency department. Blood-culture results may affect clinical decision making. From January 1, 2015 to December 31, 2015, the contamination rate of blood culture in our emergency department was 5.63%, which exceeded the maximum of 3% suggested by the American Society for Microbiology and the clinical laboratory at our hospital. PURPOSE: Using a quality improvement strategy, this project aimed to (1) identify potential factors contributing to the high blood culture contamination rate and (2) achieve a blood culture contamination rate below 3%. RESOLUTION: The factors that were identified as potentially contributing to the high blood culture contamination rate were: (a) Nursing staff: lack of related education and training and ignorance of related clinical guidelines; (b) The system: inconsistent and non-evidence-based clinical guidelines (e.g., no requirement to use sterile gloves when obtaining blood cultures and changing disinfectants); (c) The patient: older patients, residents of long-term care facility, and patients whose blood culture were in the first set were associated with higher blood culture contamination rates. Our quality improvement strategy included: design a new bedside working plate, develop slogans and posters illustrating the proper blood-drawing procedure, make a video introducing current standard technology, provide continuing education, monitor contamination rates, and provide individual feedback and retraining for those with higher contamination rates. RESULTS: The strategy was implemented from October 1, 2016 to December 31, 2016, during which period the blood culture contamination rate reduced from 5.63% to 1.51%. CONCLUSIONS: Conclusion: Improving equipment, using multiple teaching methods, and providing regular feedback not only significantly reduced the blood culture contamination rate but also enhanced the knowledge and skills of nursing staff in terms of blood culture sampling. We hope that our results are referenced by other nursing departments and used to improve the blood culture contamination rates in other clinical settings.

Manejo del reservorio venoso subcutáneo por las enfermeras / Subcutaneous venous reservoir management by nursing staff

Introducción: Los reservorios venosos subcutáneos (RVS) son una alternativa útil durante el tratamiento prolongado o crónico que requiere acceso vascular. Debido a los múltiples movimientos de personal en los hospitales, hemos advertido que las enfermeras de nueva incorporación y sustitutas de verano tienen dificultad en el manejo de los reservorios, ya que muchas no lo han utilizado anteriormente o coexisten diferentes protocolos. Objetivo: Mejorar el conocimiento y difusión de esta vía de abordaje del sistema venoso central para facilitar el manejo del RVS a las enfermeras; unificar los criterios del manejo del RVS; aprender a resolver los problemas que puedan surgir en el manejo del reservorio, así como aprender la colocación y retirada correctas de los bombas de infusión elastomérica (bombas de perfusión continua con quimioterapia). Material: Se creó un grupo de trabajo de enfermeras con experiencia. Se hizo una revisión detallada de la literatura para resumir la evidencia científica relevante. El grupo identificó los aspectos más relevantes del manejo de RVS y se unificaron criterios. Para finalizar, se propuso y elaboró una guía de actuación. Resultados: Realización de una guía del manejo del RVS para unificar criterios y ayudar en su manejo. Conclusiones: Una guía estandarizada sobre el manejo de RVS aumenta los conocimientos suficientes sobre la técnica de punción y sellado del reservorio subcutáneo, aumenta la calidad y la seguridad de los enfermeros a la hora de manejar estos dispositivos y disminuye la variabilidad en la práctica clínica, con el consecuente aumento de seguridad y disminución de la ansiedad por parte del paciente

Introduction: Subcutaneous venous reservoirs (SVR) is a useful alternative to chronic or long-term venous access. It has been observed that newly incorporated nurses and summer-time substitutes confront higher difficulties in SVR management due to: frequent changes in hospital staff, lack of previous knowledge and/or coexistence of different protocols. Developing a common protocol could help to reduce possible complications related to SVR management. Objetives: To improve knowledge and information dissemination on SVR with the aim of easing SVR management for nursing staff; to unify the SVR management criteria providing resources to solve most frequent complications and problems derived from it; and to learn about proper application and removal of elastomeric infusion pumps (continuous perfusion pumps for chemotherapy). Methods: A task force conformed by experienced nurses was established, which conducted a detailed literature review to summarize all available relevant evidence. The most salient aspects on SVR management were identified, unifying criteria through agreement by all task force members. During the last stage of the assessment, a clinical practice guideline was proposed. Results: A guideline based on unified criteria for SVR management was developed. Conclusion: A standardized guideline for SVR management increases knowledge on puncture technique and sealing procedures, improving nursing staff quality and security while handling these devices. A reduction in clinical practice variability improves safety and diminishes patients’ anxiety

Volumen de sangre extraído al paciente crítico las primeras 24h de ingreso / Blood volume extracted from the critical patient in the first 24 hours after admission

Objetivo: Calcular el número de analíticas y volumen de sangre extraído durante las primeras 24h de ingreso en la unidad de cuidados intensivos (UCI). Analizar valores de hemoglobina basal y a las 24h, relacionarlas con volumen de sangre extraído, balance ponderal e índices de gravedad. Método Estudio descriptivo, observacional y prospectivo. Variables de estudio: edad, sexo, diagnóstico de ingreso, analítica extraída, cantidad de desecho antes de la extracción de muestras, volumen de sangre total extraída en 24h, balance ponderal, índices de gravedad, hemoglobina basal y a las 24h. Análisis estadístico realizado mediante SPSS vs.20.0. Se han calculado las correlaciones de las variables sexo, balance, número de analíticas y variación de hemoglobina. Resultados La muestra estuvo formada por 100 pacientes. El número de extracciones medio por paciente/día fue de 7,2 (±2,6). La cantidad media de desecho fue de 32,61ml (±15,8). El volumen medio de sangre utilizado para determinaciones fue de 48,18ml (±16,74). El valor de la hemoglobina disminuyó las primeras 24h de ingreso, siendo mayor en los hombres (p<0,05). No se pudo demostrar que el número de analíticas estuviera relacionado con la diferencia de hemoglobina a las 24h. Los índices de gravedad tuvieron significación estadística en cuanto a los niveles de hemoglobina (Hb1: -0,3; p=0,001; Hb2: -0,4; p=0,001). Conclusiones: Del volumen total de sangre extraída en UCI, el 40% pertenece a volumen de desecho y el 60% a sangre utilizada para analíticas. Existe una disminución de la hemoglobina a las 24h de ingreso del paciente crítico, pero no se ha podido demostrar estadísticamente su relación con el número de analíticas (AU)

Objective: To calculate the number of analytical tests and blood volume drawn during the first 24hours of admission to the Intensive Care Unit (ICU). To analyse values of basal haemoglobin and at 24hours, relate them to blood loss, weight variation, and scoring system. Method: An observational descriptive pilot study. Variables studied: age, sex, diagnosis on admission, analytical tests extracted, waste quantity before the extraction of samples, total volume blood extracted in 24hours, weight variation, APACHE, SAPS, basal haemoglobin and at 24hours. Statistical analysis with SPSS vs 20.0. Variables correlation sex, weight variation, the number of analytical tests and haemoglobin change. Results: The study included 100 patients. The average number of extractions per patient/day was 7.2 (±2.6). The average waste quantity was 32.61ml (±15.8). The blood volume used for determinations was 48.18ml / 24h (±16.74). The haemoglobin value decreased in the first 24hours of admission, being higher in men (P<.05). The scoring systems were statistically significant for levels of haemoglobin (Hb1 -0.3; P=.001; Hb2 -0.4; P=.001). Conclusions: Of the total volume of blood extracted in ICU, 40% belongs to a volume of waste and 60% of blood is used for analytical tests. There is a decrease in haemoglobin exists 24hours after admission of the critical patient. Statistically, it has not been possible to demonstrate its relation with the number of analytical tests (AU)

Serum Cyclosporine Levels: The Influence of the Time Interval Between Interrupting the Infusion and Obtaining the Samples: A Randomized Clinical Trial.

BACKGROUND: There are controversies regarding the best way to collect blood samples for cyclosporine A (CsA) serum levels when this immunosuppressant is administered continuously through a silicone central venous catheter (CVC) to hematopoietic stem cell transplant recipients. OBJECTIVE: The aim of this study was to verify the effect of the time elapsed between the interruption of a continuous intravenous CsA infusion and the collection of blood samples on CsA serum levels. METHODS: This randomized 2-group clinical trial involved 32 adults. In group A, blood samples were collected immediately after interrupting the medication from peripheral vein and CVC lines. In group B, the same procedures were performed 5 minutes after interrupting the infusion. RESULTS: We did not observe influence of the time elapsed between interruption of the infusion and collection of the samples, independent of the collection mode and the volume discarded (P > .05). The line used for the infusion maintained a constant high level when compared with different moments of collection (P > .05), whereas in the other lines, there was a significant increase when compared with the levels obtained at 24 hours and 7 days after CsA start (P = .00). CONCLUSION: The CVC line free from cyclosporine can safely be used to collect blood. The procedure can be performed immediately after interrupting the infusion, and discarding 5 mL is sufficient to obtain accurate levels. IMPLICATIONS FOR PRACTICE: The results can help nurses choose how to collect blood samples through the CVC, thus preventing patients from having a painful and stressful procedure such as peripheral venipuncture.

A feasibility and efficacy randomised controlled trial of swaddling for controlling procedural pain in preterm infants.

AIMS AND OBJECTIVES: This study aimed to investigate the feasibility and efficacy of swaddling to control procedural pain among preterm infants. BACKGROUND: Swaddling has been recommended for controlling neonatal pain. However, the feasibility for use is uncertain and insufficient evidence is available among preterm infants. DESIGN: A two-arm randomised controlled trial with repeated measures. METHOD: The study was conducted in a 21-bed neonatal intensive care unit of a regional hospital in Hong Kong. Preterm infants who required heelstick procedure were eligible. Fifty-four preterm infants between 30-37 gestational weeks were randomly assigned to swaddling (n = 27) and control (standard care, n = 27) groups. Pain assessment was performed pre, during, immediate, two, four, six and eight minutes after heelstick procedure using the Premature Infant Pain Profile. RESULTS: The mean Premature Infant Pain Profile scores were significantly reduced in the intervention group compared to the control group during, immediate, two, four, and six minutes after the heelstick procedure. The mean changes of heart rate and oxygen saturation in the intervention group were significantly lower than that of the control group at all measured time points. Notably, the swaddled infants quickly resumed to the baseline level at two minutes whereas the control group reached the stable state at an extended period of six minutes. CONCLUSION: The findings show that swaddling is feasible and efficacious in controlling pain for heelstick procedure among preterm infants. No adverse effects were observed. RELEVANCE TO CLINICAL PRACTICE: This article presents the feasibility and efficacy of swaddling as a non-pharmacological and non-invasive intervention to relieve pain during the heelstick procedures among preterm infants. Swaddling can contribute to control minor procedural pain in neonates as one of the simple, safe, cost effective, humanistic and natural analgesia alternatives.

[Influence of an observer in the haemolysis produced during the extraction of blood samples in primary care]. / Influencia de un observador en la hemólisis producida durante las extracciones de muestras sanguíneas en atención primaria.

OBJECTIVE: To check whether an intervention based on direct observation and complementary information to nurses helps reduce haemolysis when drawing blood specimens. MATERIAL AND METHODS: Random sampling study in primary care centres in the serrania de Málaga health management area, using a cross-sectional, longitudinal pre- and post-intervention design. The study period was from August 2012 to January 2015. The level of free haemoglobin was measured by direct spectrophotometry in the specimens extracted. It was then checked whether the intervention influenced the level of haemolysis, and if this was maintained over time. RESULTS: The mean haemolysis measured pre-intervention was 17%, and after intervention it was 6.1%. A year later and under the same conditions, the frequency of haemolysis was measured again the samples analysed, and the percentage was 9% These results are low when compared to the level obtained pre-intervention, but are higher when compared to the levels obtained immediately after the intervention. The transport and analysis conditions were the same. CONCLUSIONS: An intervention based on a direct and informative observation in the process of collecting blood samples contributes significantly to reduce the level of haemolysis. This effect is maintained in time. This intervention needs to be repeated to maintain its effectiveness. Audits and continuing education programs are useful for quality assurance procedures, and maintain the level of care needed for a good quality of care.

Hemolysis from a nurses' standpoint--survey from four Croatian hospitals.

INTRODUCTION: Hemolysis can occur during sample collection, handling and transport. It is more frequent when the non-laboratory staff performs sampling. The aim of this study was to assess nurses' knowledge on the causes of hemolysis and consequential impact on the laboratory tests results. Additionally, the differences in knowledge, related to work experience, professional degree and previous education about hemolysis were explored. MATERIALS AND METHODS: An anonymus survey, containing 11 questions on demographics, causes of hemolysis, its impact on biochemical parameters and nurses' attitude towards additional education in preanalytics, was conducted in four Croatian hospitals. The answers were compared by Chi-squared and Fischer exact test. RESULTS: In total, 562 survey results were collected. Majority of nurses declared familiarity with the term "hemolysis" (99.6%). There were 77% of correct answers regarding questions about the causes of hemolysis, but only 50% when it comes to questions about interference in biochemical tests. The percentage of correct answers about causes was significantly lower (P=0.029) among more experienced nurses, and higher (P=0.027) in those with higher professional degree, while influence of previous education was not significant. Also, higher percentage of correct answers about interferences was encountered in nurses with longer work experience (P=0.039). More than 70% of nurses declared that additional education about preanalytical factors would be beneficial. CONCLUSION: Croatian nurses are familiar with the definition of hemolysis, but a lack of knowledge about causes and influence on laboratory test results is evident. Nurses are eager to improve their knowledge in this field of preanalytical phase.

[Pre-analytical errors in blood sampling: an observational study on specimen collection technique and laboratory results]. / Gli errori preanalitici nel prelievo ematico: uno studio osservazionale sulle modalità di raccolta dei campioni e sugli esiti di laboratorio.

INTRODUCTION: Around 60-70% of diagnostic and therapeutic decisions are based on blood exams. Several errors occur during the pre-analytic phase. AIMS: of this study were: to describe nurses' behaviours in blood specimen collection; to describe prevalence and type of pre-analytical errors; to assess the association between pre-analytical errors and occurrence of unsuitable specimens. METHODS: An observational cross-sectional study was conducted by means of a structured form based on up-to-date clinical recommendations. A researcher observed nurses' behaviors during 172 blood sampling procedures in medical, surgical and emergency care settings. Unsuitable procedures were registered. RESULTS: Most behaviours were correct, however some significantly diverged from recommended practices: active and passive patient identification; respect of antiseptic solution's drying time; rapid removal of tourniquet when blood started flowing. The prevalence of unsuitable specimen reports was significantly higher when the procedure involved a small calibre vein (RP: 0.19; IC95% 0.04 - 0.98; p = 0.03) and when blood drawing was difficult (RP; 3.83; IC95% 1.63 - 9.01; p <0.001). CONCLUSIONS: The pre-analytical phase is important for the diagnostic process and safety of patients. Although some factors ­ as patients' characteristics ­ are non-modifiable, some nurses' behaviours could be improved to reduce risk of pre-analytical errors. Further studies are needed to clarify the associations between pre-analytical errors and laboratory outcomes.

[Can a blood sample for diagnostic exams be drawn from a peripheral venous catheter?]. / Si può eseguire un prelievo a scopo diagnostico da un catetere venoso periferico?

INTRODUCTION: Often the blood sample in patients exposed to serial blood exams is taken from the venous cannula (PVC) to avoid a second venipuncture. AIM: To assess whether blood draws from PVCs are more haemolized than those drawn from phlebotomy, and if the blood drawn from a cannula interferes with the test results. METHODS: A bibliographic search was conducted in PubMed, Cinhal and Ovid, with the following key words: Peripheral Catheter, Blood Specimen Collection, Blood Sample, Haemolysis, 19 articles were identified (including 2 meta analyses), selecting the articles involving emergency departments. RESULTS: The meta-analyses agree on the lower risk for haemolysis in blood drawn from a needle: risk reduction of 84% (RR=0.16, IC 95% 0.11-0.24) (Heyer et al); the blood draw from PVC increased the risk for hemolysis of 7% (RR 1.07 IC 95% 1.06-1.08, p<0.001) (Lippi et al). Manual aspiration reduces the risk for hemolysis compared to the vacutainer equipment. However, the results of tests drawn from PVC are not significantly different compared to the classical phlebotomy. CONCLUSIONS: Blood draws from PVC bear an higher risk for heamolysis but can be safely used for most diagnostic exams, with the exception of blood gase.

Taking blood, taking stock.

Selina Reyes reports back on her venipuncture course and the challenges of taking blood. In a small community, could her very first patient be someone that she knows? What are the chances?

[Risk of hemolysis in blood sampling from peripheral intravenous catheter: a literature review]. / Il rischio di emolisi nel prelievo di sangue da catetere venoso periferico: revisione della letteratura.

SCOPE: Hemolysis is one of the main factors that can damage a blood sample. The availability of an intravenous line already placed pushes many nurses to use this route for blood drawing, even if it is known that this technique is associated with an increased rate of hemolysis compared to blood sampling with a needle. The aim of this work is to identify interventions that reduce risk of hemolysis if the blood sample is from a peripheral IV catheter. METHOD: A review of relevant literature was conducted through the databases MEDLINE, CINAHL and Cochrane database of Systematic Reviews. RESULTS: Fifteen studies were retrieved. Factors such as the material and the caliber of the IV catheter, the presence of obstructions, the anatomical site, the permanence of the tourniquet, the difficulty of positioning of the catheter, the volume of the tube used and the skills of the operator are decisive in the risk of hemolysis of the sample. In term of cost and preferences of the patient, the technique of blood sampling from a peripheral IV catheter is preferable. CONCLUSIONS: Sample collection through intravenous catheters is associated with significant higher risk of hemolysis. Take a sample of blood from a peripheral catheter to carry out an analysis and, at the same time, reduce the risk of hemolysis is possible if some precautions are followed.

Blood transfusion sampling and a greater role for error recovery.

INTRODUCTION: Patient identification errors in pre-transfusion blood sampling ('wrong blood in tube') are a persistent area of risk. These errors can potentially result in life-threatening complications. Current measures to address root causes of incidents and near misses have not resolved this problem and there is a need to look afresh at this issue. PROJECT PURPOSE: This narrative review of the literature is part of a wider system-improvement project designed to explore and seek a better understanding of the factors that contribute to transfusion sampling error as a prerequisite to examining current and potential approaches to error reduction. SEARCH STRATEGY: A broad search of the literature was undertaken to identify themes relating to this phenomenon. KEY DISCOVERIES: Two key themes emerged from the literature. Firstly, despite multi-faceted causes of error, the consistent element is the ever-present potential for human error. Secondly, current focus on error prevention could potentially be augmented with greater attention to error recovery. CONCLUSIONS: Exploring ways in which clinical staff taking samples might learn how to better identify their own errors is proposed to add to current safety initiatives.

Fiabilidad de los resultados analíticos de muestra sanguínea desechando el doble del espacio muerto del catéter / Reliability of laboratory findings from blood samples when only the double dead space in catheter is discarded

OOBJETIVO: determinar la fiabilidad de dos métodos de extracción desangre a través de catéter arterial en los pacientes ingresados en una unidad de reanimación postquirúrgica. MATERIAL Y MÉTODO: estudio cuasi experimental realizado en el Hospital de la Princesa de Madrid, de febrero a mayo de 2010, en el que se compararon dos métodos de extracción de muestra de sangre para análisis a través de catéter arterial periférico, realizados secuencialmente: primero la intervención= 2 cc sangre desechada + 13,5 muestra a analizar, y segundo el control= inmediatamente después de la extracción previa= 15,5 cc + 13,5 muestra a analizar, en relación a los resultados de parámetros analíticos bioquímicos, hematológicos y de coagulación. RESULTADOS: la diferencia de las medias es muy pequeña en todos los parámetros estudiados; en todos los casos el "0" se encuentra incluido en los respectivos intervalos de confianza, no siendo estadísticamente significativos (p> 0,05). Las correlaciones son superiores a 0,93 en todos los parámetros estudiados en el caso de la bioquímica, superiores a0,84 en el caso de la hematimetría y superiores a 0,90 en el caso de la coagulación, obteniendo en todos los casos unos valores de p< de 0,05.CONCLUSIONES: para garantizar la calidad de los resultados de laboratorio es suficiente desechar el volumen correspondiente al doble del espacio muerto del sistema (en el presente estudio 2 cc)

PURPOSE: to assess reliability of two blood sample drawing methods though an arterial catheter in patients admitted to a postoperative resuscitation unit. MATERIAL AND METHODS: a quasi-experimental study was carried out at Hospital de la Princesa, Madrid, Spain, from February to May 2010.Two sequentially used methods for drawing blood samples for laboratory tests through a peripheral arterial catheter were compared: firstly the intervention procedure = 2 cc of blood discarded + a 13.5 sample for laboratory testing; and secondly the control procedure = immediately after previous sample drawing = 15.5 cc + a 13.5 sample for laboratory testing. Biochemistry, hematology and coagulation laboratory parameters were compared. RESULTS: differences in mean values were very low for all assessed parameters. Zero value is always included in confidence intervals; therefore, differences were not statistically significant (p > 0.05). Correlation is higher than 0.93 for all assessed biochemistry parameters, higher than 0.84 for hematology parameters, and higher than 0.90 for coagulation parameters (p < 0.05 for all comparisons).CONCLUSIONS: discarding the volume corresponding to the doubledead space in the system (2 cc in our study) is adequate to ensure quality in laboratory testing results

One poke or two: can intravenous catheters provide an acceptable blood sample? A data set presentation, review of previous data sets, and discussion.

INTRODUCTION: The purpose of this study was to show that acceptable blood samples can be collected through intravenous (i.v.) catheters. Hemolysis of blood samples and appropriate methods of blood sample collection can be a topic of controversy in an emergency department and throughout a hospital. This investigation was conducted by laboratory personnel and ED nursing staff at a moderately sized hospital in the northwestern United States. Nearly 9,000 blood draws were collected and categorized between May and August 2011 to determine hemolysis rates. At the start of this project, there was some question about whether blood collected from i.v. catheter starts in the emergency department provided an acceptable laboratory sample. By the end of the project, it was clear that low rates of hemolysis were consistently achievable by each of the 3 methods investigated. METHODS: Information was collected electronically as part of the standard laboratory intake and processing of samples. The level of hemolysis in a blood sample was measured spectrophotometrically by automated laboratory equipment as part of the sample intake process. The data were then cataloged and presented monthly. Because of the simplicity of this project and the clarity of the results, only simple summary statistics were performed to assist in interpretation of the data. RESULTS: The rates of blood samples rejected because of hemolysis were as follows: 1.1% when collected from an IV catheter start, 0.8% when collected from an existing vascular access, and 0.1% when collected by venipuncture with a steel needle. DISCUSSION: The data show that low rates of samples rejected because of hemolysis are achievable by the collection of blood from an i.v. catheter start. With all 3 collection methods studied, the sample rejection rates because of hemolysis were well below the 2% level that has been cited as a benchmark best practice of the American Society of Clinical Pathology. The results of this investigation clearly support the use of blood samples collected from i.v. starts.