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Body modification

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Nearly twenty years ago, a court was faced with an agonising decision: whether the proposed separation of conjoined twins was lawful
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Radiologically inserted gastrostomy (RIG) tube - patient information

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This factsheet provides information about having a radiologically inserted gastrostomy (RIG) tube and what you can expect at your appointment.
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Caring for your suprapubic catheter - patient information

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Guide to caring for your suprapubic urinary catheter
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Caring for your urinary catheter - patient information

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Guide to caring for your urinary catheter
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Procedure for start-up, tuning and shut down of profile 3 SIFT FAMS analyser

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NIHR Southampton Biomedical Research Centre The NIHR Southampton Biomedical Research Centre (BRC) has a tight quality assurance system for the writing, reviewing and updating of Standard Operating Procedures. As such, version-controlled and QA authorised Standard Operating Procedures are internal to the BRC. The Standard Operating Procedure from which information in this document has been extracted, is a version controlled document, managed within a Quality Management System. However, extracts that document the technical aspects can be made more widely available. Standard Operating Procedures are more than a set of detailed instructions; they also provide a necessary record of their origination, amendment and usage within the setting in which they are used. They are an important component of any Quality Assurance Framework, but in themselves are insufficient and need to be used and interpreted with care. Alongside the extracts from our Standard Operating Procedures, we have also made available here an example Standard Operating Procedure and a word version of a Standard Operating Procedure template. Using the example and the Standard Operating Procedure template, institutions can generate their own Standard Operating Procedures and customise them, in line with their own institutions. Simply offering a list of instructions to follow does not assure that the user is able to generate a value that is either accurate or precise so here in the BRC we require that Standard Operating Procedures are accompanied by face-to-face training. This is provided by someone with a qualification in the area or by someone with extensive experience in making the measurements. Training is followed by a short competency assessment and performance is monitored and maintained using annual refresher sessions. If you require any extra information, clarification or are interested in attending a training session, please contact Dr Kesta Durkin (k.l.durkin@soton.ac.uk). This document has been prepared from Version 3 of the BRC Standard Operating Procedure for start-up, tuning and shut-down of the profile 3 SIFT/FA-MS analyser. It was last reviewed in July 2014 and the next review date is set for July 2016. The version number only changes if any amendments are made when the document is reviewed. Page 1 of 13 NIHR Southampton Biomedical Research Centre NIHR Southampton Biomedical Research Centre Procedure for START-UP, TUNING AND SHUT DOWN OF THE PROFILE 3 SIFT/FA-MS ANALYSER BACKGROUND This procedure is for the start-up and tuning of the Profile 3 SIFT/FAMS-MS prior to use to measure volatile compounds in breath samples, either by direct breathing into the instrument, by sampling from breath collection bags or by sampling the headspace above a solution. This instrument samples gas mixtures such a breath, converts compounds present in the gas to ions, separates the ions according to their weight (m/z) and measures the number of each ion generated as a count rate (cps). The count rates can be used to calculate the concentration of designated compounds in the gas mixture. Data acquisition modes The instrument can either collect data on a continuous range of ion weights (Mass Spectrum mode: e.g. m/z 10 to m/z 150) or on a smaller number of specific values of m/z (Time profile or Multi ion monitoring mode). Sampling Modes For each data acquisition mode, breath may be sampled either by breathing directly into the instrument's sample head or by connecting the sample head to a breath bag containing a breath sample. In addition, measurements can be made on the vapour in the headspace above a liquid held in a glass sample bottle. In the latter case, a needle is connected to the instrument sample head and used to pierce a silicone septum that seals the sample bottle. Page 2 of 13 NIHR Southampton Biomedical Research Centre PURPOSE To ensure correct and reproducible operating conditions of the SIFT/FA-MS analyser. SCOPE This procedure applies to any study that requires the operation of the Profile 3 SIFT/FAMS analyser. RESPONSIBILITIES It is the responsibility of the operator to use this procedure when preparing the instrument for subsequent measurements of volatile compounds in breath or in the enclosed headspace above a solution. If the operator is not the person who will be making the subsequent measurements, it is the responsibility of the operator to ensure that the measurer has adequate knowledge and ability to do so. PROCEDURE Introduction The Profile 3 SIFT/FA-MS Analyser is used in the standard mode for making measurements of volatile organic compounds in breath or in the headspace above liquids in a container. Additionally, an alternative mode is provided through the operating software for the specific measurement of the abundance of deuterated water (D2O: deuterium oxide). This measurement is most usually made with the purpose of measuring the total body water volume by the isotope dilution technique. Make sure that you know which mode is to be used. OPERATIONAL SEQUENCE 1. Check that the level of water in the reagent bowl located at the top left side of the instrument panel is on or between the two black marks. These approximately indicate a volume range between 10 and 15 ml. If volume is insufficient, make sure that the instrument is turned off (pumps not running), unscrew the bowl, top up to the top line and reassemble. Check that both the Profile 3 SIFT/FA-MS and the computer are plugged into the mains supply and that the power is turned on at the wall switches. Check that the grey Ethernet cable is plugged into the left side of the computer. If the instrument is to be used for D2O abundance measurements, the source partial pressure line that protrudes from the left side of the instrument body should the closed by fitting an appropriate screw into the block. If the instrument is to be used for Page 3 of 13 NIHR Southampton Biomedical Research Centre general SIFT measurements the line must be open to allow inflow of atmospheric oxygen and nitric oxide. 2. Turn on the computer by pressing the power on/off button. Go to the right side of the instrument. The arrow at the bottom of the side panel indicates where the mains power on/off switch can be located on the back panel of the instrument. Turn on the SIFT/FA-MS at the power on/off switch which is located beside the power input socket. There will be an immediate sound of the vacuum pumps operating. 3. Observe the SIFT/FA-MS status indicator light at the top front left of the instrument. When it shows a solid green light, click on the SIFT-MS icon on the computer screen to load the SIFT/FA-MS operating software. 4. The SIFT/FA-MS operating software should automatically connect to the SIFT/FA-MS (via the View/Preferences/Automatically Connect setting). If this does not happen, the numbers in the black read-back boxes at the top of the screen will show 0 (zero). In this case, click on the CONNECT button. If connection again fails, check the grey Ethernet cable connection and /or reboot the computer before trying again. If still unsuccessful, refer to the Instrument Manual and then seek help. 5. Click `Instrument Settings' entry in the left side control panel. If it is not visible then click on the arrows at the side of the `Instrument' heading to drop down the entries. Page 4 of 13 NIHR Southampton Biomedical Research Centre The screen should open in the `Injection settings' mode but to make sure, click the `Injection settings' tab in the middle of the screen. On the computer screen enter a value of 4.7 in the white box under the heading `Source valve'. This may easily be done by using the mouse left button to highlight the existing value and then typing in the required value. Similarly in the white box to the right, marked `Source preset', enter the value 0.24. Note that a zero value will disable the preset and default source valve voltage value of 4.7 will apply until manually adjusted to give a working source pressure value of 0.24 following stabilisation of source conditions. Page 5 of 13 NIHR Southampton Biomedical Research Centre 6. The software will control and monitor the pump-down process. During this time the pumps are reducing the pressure to a level that will sustain a stable microwave discharge 7. The green light on the SIFT/FA-MS will flash and the SIFT/FA-MS will continue to pump down for 5 minutes. The time from switch-on of the SIFT/FA-MS is shown at the bottom left side of the computer display. 8. After 5 minutes a caption box appears, prompting the user to turn on the helium supply and start the instrument. Keep the caption box open but do not click anything yet. 9. a) If the instrument is installed in SCBR Consulting Room 16 the helium supply is turned on and off using the hand wheel on the top of the cylinder and not the black knob on the regulator valve. The wheel is turned anti-clockwise to open. b) If the instrument is in the SCBR Mass Spec laboratory the supply is turned on and off at the wall supply using the blue lever control. When ready to proceed, turn on the helium supply and check that the pressure in the supply line is 2 bar on the pressure gauge. In the daily record sheet, enter the value shown under SOURCE in the panel of readback boxes (box on extreme left side). It is important to do this. In the caption box (Step 8 above), click `Yes' to activate the source microwave discharge. In some situations, e.g. when the software has not been turned on until after the instrument has been pumping down for five minutes or when the discharge has either failed to strike or has been lost during operation, there will not be a caption box. In this case simply ensure that the helium supply is turned on at the cylinder or wall tap and click the `Start' button at the top of the left side control panel. Page 6 of 13 NIHR Southampton Biomedical Research Centre 10. A script box will open on screen indicating the progress of the start-up. It will report the voltage ramp on the source and the attempt to strike the source discharge. This is not always successful. If successful, a pink glow from the source can be seen through the grill at the top of the left side panel of the SIFT/FA-MS. In the read-backs, pico A will start to rise. 11. If start-up is not successful, the pico A will remain about 0. Wait until the script box has closed and the SIFT-MS indicator light shows solid green. Repeat the start-up using the `Start' button on the upper left side of the screen. 12. When start-up is successful, click `Instrument settings' in the left side control panel. The instrument settings window opens. It has two tabs located in the middle of the screen. Click the tab marked injection settings. At the top of the screen, watch the source pressure reading in the black box on the extreme left of the row of readbacks. Wait for the source pressure to stabilise. This should initially fall rapidly and the pink glow will darken slightly as the pressure changes. It will then decrease more slowly and stabilise at a value of 0.24. On some occasions, the discharge may go out before stable conditions have been reached. If this happens, reset the source voltage to a value of about 4.6 and set the Source Preset to 0 (disabled). Re-ignite the source discharge by clicking the Start button. When the source pressure in the read-back box has become relatively stable, note this value and enter it in the Source Preset box that was earlier set to zero. Now, manually decrease this value towards 0.24, waiting for the value in the Source Pressure box to stabilise at each new Source preset value. It may take a bit of practice to find how quickly you can reduce this setting! If it is reduced too quickly the discharge may be lost again and it will be necessary to repeat the process . Page 7 of 13 NIHR Southampton Biomedical Research Centre 13. House keeping checks: check the read-backs on the computer as followsSource pressure: 0.24 Flow tube pressure: about 1(This will be about 0 if helium supply is off). T-inlet at set value: uW%: Sample T: currently 70oC 26 initially between 20-30oC Nano A and Pico A: These should be about 12 and 25, but the actual values depend on the sample flow rate. If the source fails to ignite, this will stay at 0. If necessary, adjust the flow tube pressure to read 1.0 using the black wheel on the helium cylinder regulator if in Consulting Room 16 (clockwise to increase) or the large regulator wheel at the wall tap if in the Mass Spectrometry laboratory. Make sure that you record the readings above in the daily settings log-kept adjacent to the SIFT/FA-MS instrument. Page 8 of 13 NIHR Southampton Biomedical Research Centre TUNING Click `SCAN' mode from the items under `Take A Sample' in the left side control panel. If the entry is not visible then click on the arrows at the right of the `Take A Sample' heading. 100. Set the Scan range from m/z 10 to m/z Click on the H3O+ precursor button to select this precursor. The value 19 should show in the `prec.' read-back box. Click `Monitor' from under the MS Control heading. If the entry is not visible then click on the arrows at the right of the `MS Control' heading. Use the `Log' button from the toolbar to select the log scale for the Yaxis. When in the log scale, many peaks can be seen, in the linear scale only 3 or 4 peaks are clearly apparent. Briefly check that peaks can be seen at m/z 19 and 73 (37 and 55 should also be seen). The m/z 19 peak should be 1E+6 or greater. If not, check that the H3O+ precursor has been selected and that 19 is showing in the prec. read-back box. If still not showing the required peaks then check the m/z calibration settings (see below) against the last recorded good values in the daily instrument log. Click `STOP', Page 9 of 13 NIHR Southampton Biomedical Research Centre Set `Number of scans' to 3 (use up/down arrows or type into box) and set `Time of each scan' to 10 sec. Click `Average Scan'. When the scan is complete, expand the window to Full Screen mode using the rectangular Windows button second from right in the extreme top right of the active software window. Note: it may be helpful to breathe into the mouthpiece of the sample head to obtain a large m/z 73 peak. This can be done by watching the scan and breathing just before and during the scanning of the mz 73 region. Set the Y-axis scale to LINEAR mode by clicking the Log button appropriately. Only 4 or 5 peaks should now be seen. Check the resolution of peaks m/z 19 and m/z 73. Use the mouse to highlight the area around m/z 19 (position the mouse pointer to the left of the peak at m/z 19, press and hold the left mouse button and drag the pointer to the right of the peak and then release the mouse button). The highlighted area will appear with a white background. Expand this area by pressing the `Expand' button and then in the same way exactly highlight and expand the area m/z 18 to m/z 20. Read the peak maximum height against the Y axis and calculate half this value (halfheight). Place the transparent acetate sheet horizontally across the computer screen with the calibrated edge uppermost and level with the Yaxis value of the peak half-height. The acetate is marked at 0.1 m/z units. Position the acetate horizontally so that the width of the peak at the half-height can be estimated from the scale. For m/z 19, this should be about 0.55 mass units (mu) but 0.5 to 0.6mu is acceptable. Repeat as above for the peak at m/z 73, expanding the range m/z 72 to 74 mu. W1/2 for m/z 73 should be in the range 0.55 to 0.6 mu. If the resolution needs to be altered, then go to Instrument Settings/Detector settings tab and click `Touch up Resolution'. Page 10 of 13 NIHR Southampton Biomedical Research Centre This will open a pop-up which will allow the resolution to be improved by selecting `narrower' or `wider' for the peaks at 19 m/z and 73 m/z. Adjust as necessary and obtain a new spectrum. Reassess the peak width in this new spectrum and adjust it again until you are satisfied. Record the values under Delta M Resolution in the daily record log. Next, check and adjust the accuracy of the peak mass alignment. This should be done after any adjustment to the peak resolution which may affect the peak alignment. Set the No of scans to 3 and click AVERAGE SCAN. When scan is complete, ensure the Y-axis is in the linear mode. Expand the area around m/z 19 so that the peak maximum can be clearly identified. The curve of the peak is not continuous, so identify and note the m/z value corresponding to where the top of the peak appears to be (new m/z 19). If it is more than 0.1 mass units different from 19.0, it will need to be reset. Repeat the process for m/z 73. In the Instrument Settings/Detector settings tab, click the Calibrate Q2 button and enter any required m/z re-calibration values noted above (new m/z 19, new m/z 73) into the right hand boxes of the calibration function, for example, if the peak value of m/z 73 appeared to be at 72.85 mu, then the entry should be ? Read m/z 73 as m/z 72.85 When complete, click OK. A box will open showing the new calibration parameters. Record them in the daily setting log and click OK to exit. Page 11 of 13 NIHR Southampton Biomedical Research Centre Re-run the spectrum scan to ensure that the new settings remain suitable. If not, repeat the calibration. In turn, select the H3O+, NO+ and O2+ precursors and carry out average scans (X3). Record the precursor peak heights in the daily record sheet (m/z 19, 30 and 32 respectively). Check that the rear blanking plug is not fitted to the sample head and fit a new disposable mouthpiece to the front of the head. Click on MIM Profile Tab, click on Select Compounds in the Take a Sample panel on the left hand side and select Water from the list of compounds available in the drop-down menu. Sample alternate periods of room air, breath, room air, breath and room air. Make sure that the `Correct' function is operative (correction values displayed). Select the `ppb' display mode and highlight the breath sample peaks. Check that the measured water concentrations fall in the range 5.5 to 6%. If not, adjust the flow rate in the configuration file (See instrument manual) and repeat until a withinrange value is obtained. Record the altered setting in the daily settings record. Turn off the `ppb' display to show the individual and total ion traces. Highlight to alternately select breath and room air samples and record the Total counts of each sample in the daily settings record. The instrument is now set-up and tuned and ready for use to measure samples in the standard SIFT mode. Measurements should be carried out as described in the SOP appropriate to the specific study being undertaken. If measurements of D2O abundance measurements are required, the mode should be set up by clicking on the `MIM Profile' tab, clicking the D/H in the upper middle of the screen and then clicking the `Set D/H' button under the `MS Control' heading on the left side of the screen. Measurements should be carried out as described in the SOP appropriate to the specific study being undertaken. ROUTINE SWITCH OFF 1. Click the Shut down button on the left side dashboard and wait for a solid green light to show on the SIFT/FA-MS. The plasma should no longer glow. 2. Exit the SIFT/FA-MS software, switch off the helium supply at the wall tap or cylinder as appropriate to the location and wait for a solid green light on the SIFT/FA-MS. 3. Turn off the SIFT/FA-MS power switch and turn off the computer. Page 12 of 13 NIHR Southampton Biomedical Research Centre EMERGENCY SWITCH OFF In an emergency, switch off the power supply to the SIFT/FA-MS and turn off the helium gas supply at the wall tap or cylinder tap. Page 13 of 13
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STHW841-V1-Biomerieux-Blood-culture-guidance

Description
BLOOD CULTURE A key investigation for diagnosis of bloodstream infections OUR SPECIAL THANKS GO TO Dr Susan M. Novak-Weekley Ph.D. D(ABMM), S(M)ASCP Vice-President, Medical Affairs, Qvella, Carlsbad, CA, USA Wm. Michael Dunne, Jr. Ph.D. D(ABMM), F(AAM, CCM, IDSA, PIDJ) Senior Fellow, Clinical Microbiology, Data Analytics Group, bioMérieux, Inc., Durham, NC, USA Adjunct Professor of Pathology and Immunology, Washington University School of Medicine, St. Louis, MO, USA Adjunct Professor of Pediatrics, Duke University School of Medicine, Durham, NC, USA for their helpful advice and comprehensive review of this booklet. INTRODUCTION “…the laboratory detection of bacteremia and fungemia remains one of the most important functions of clinical microbiology laboratories... A positive blood culture establishes or confirms that there is an infectious etiology of the patient’s illness. Moreover, it provides the etiologic agent and allows antibiotic susceptibility testing for optimization of therapy.”1 The laboratory detection of bacteremia and fungemia using blood cultures is one of the most simple and commonly used investigations to establish the etiology of bloodstream infections. Rapid, accurate identification of the bacteria or fungi causing bloodstream infections provides vital clinical information required to diagnose and treat sepsis. Sepsis is a complex inflammatory process that is largely underrecognized as a major cause of morbidity and mortality worldwide. There are an estimated 19 million cases worldwide each year,2 meaning that sepsis causes 1 death every 3-4 seconds.3 Early diagnosis and appropriate treatment make a critical difference when it comes to improving sepsis patient outcomes. Chances of survival go down drastically the longer initiation of treatment is delayed. If a patient receives antimicrobial therapy within the first hour of diagnosis, chances of survival are close to 80%; this is reduced by 7.6% for every hour after. Yet, if a patient initially receives inappropriate antimicrobial treatment, they are five times less likely to survive.4 This booklet aims to: a nswer key questions commonly asked in relation to blood culture p rovide practical recommendations for routine blood culture procedures o ffer an illustrated step-by-step guide to best blood culture collection practices. This booklet is intended to be a useful reference tool for physicians, nurses, phlebotomists, laboratory personnel and all other healthcare professionals involved in the blood culture process. DEFINITIONS Bacteremia: the presence of bacteria in the blood. It may be transient, intermittent or continuous. Blood culture: blood specimen submitted for culture of microorganisms. It enables the recovery of potential pathogens from patients suspected of having bacteremia or fungemia. Blood culture series: a group of temporally related blood cultures that are collected to determine whether a patient has bacteremia or fungemia. Blood culture set: the combination of blood culture bottles (one aerobic and one anaerobic) into which a single blood collection is inoculated. Bloodstream Infection (BSI): an infection associated with bacteremia or fungemia. Contaminant: a microorganism isolated from a blood culture that was introduced during specimen collection or processing and is not considered responsible for BSI (i.e., the isolates were not present in the patient’s blood when the blood was sampled for culture). Contamination: presence of microorganisms in the bottle that entered during sampling but were not actually circulating in the patient’s bloodstream. Fungemia: the presence of fungi in the blood. Sepsis: life-threatening organ dysfunction caused by a dysregulated host response to infection.5 Septicemia: clinical syndrome characterized by fever, chills, malaise, tachycardia, etc. when circulating bacteria multiply at a rate that exceeds removal by phagocytosis.6 Septic episode: an episode of sepsis or septic shock for which a blood culture or blood culture series is drawn. Septic shock: a subset of sepsis in which underlying circulatory and cellular metabolism abnormalities are profound enough to substantially increase mortality.5 Source: Wayne, P.A. Principles and procedures for Blood Cultures; Approved Guideline, CLSI document M47-A. Clinical and Laboratory Standards Institute (CLSI); 2007 unless otherwise specified. 2 TABLE OF CONTENTS 1 BLOOD CULTURE ESSENTIALS p. 2 1 What is a blood culture? p. 4 2 Why are blood cultures important? p. 4 3 When should a blood culture be performed? p. 5 4 What volume of blood should be collected? p. 6 5 How many blood culture sets should be collected? p. 8 6 Which media to use? p. 10 7 Timing of blood cultures p. 11 8 How to collect blood cultures p. 12 9 How many days of incubation are recommended? p. 14 10 Is it a contaminant or a true pathogen? p. 15 2 SPECIAL TOPIC : INFECTIVE ENDOCARDITIS p. 18 3 PROCESSING POSITIVE BLOOD CULTURES p. 20 4 INTERPRETATION OF RESULTS p. 22 5 BLOOD CULTURE/ SEPSIS GUIDELINES p. 24 REFERENCES p. 26 RECOMMENDATIONS FOR BLOOD CULTURE COLLECTION p. 30 3 1 BLOOD CULTURE ESSENTIALS 1 What is a blood culture? A blood culture is a laboratory test in which blood, taken from the patient, is inoculated into bottles containing culture media to determine whether infection-causing microorganisms (bacteria or fungi) are present in the patient’s bloodstream. v B lood cultures are intended to: Confirm the presence of microorganisms in the bloodstream Identify the microbial etiology of the bloodstream infection 3 MAIN AIMS OF BLOOD CULTURE*: Help determine the source of • Confirm infectious etiology infection (e.g., endocarditis) • Identify the etiological agent P rovide an organism for • Guide antimicrobial susceptibility testing and optimization therapy of antimicrobial therapy * Adapted from ESCMID (European Society of Clinical Microbiology and Infectious Diseases) guidelines, 2012.7 2 Why are blood cultures important? Blood culture is the most widely used diagnostic tool for the detection of bacteremia and fungemia. It is the most important way to diagnose the etiology of bloodstream infections and sepsis and has major implications for the treatment of those patients. A positive blood culture either establishes or confirms that there is an infectious etiology for the patient’s illness.3 A positive blood culture also provides the etiologic agent for antimicrobial susceptibility testing, enabling optimization of antibiotic therapy.3 Sepsis is one of the most significant challenges in critical care, and early diagnosis is one of the most decisive factors in determining patient outcome. Early identification of pathogens in the blood can be a crucial step in assuring appropriate therapy, and beginning 4 BLOOD CULTURE ESSENTIALS effective antibiotic therapy as early as possible can have a significant impact on the outcome of the disease.8, 9 v P roviding adequate antibiotic therapy within the first 24-48 hours leads to:10-14 Decreased infection-related mortality (20-30%) Earlier recovery and shorter length of hospital stay Less risk of adverse effects Reduced risk of antimicrobial resistance Cost reduction (length of stay, therapy, diagnostic testing) Figure 1: Fast effective antimicrobial therapy increases survival chances Adapted from Kumar A, et al. Crit Care Med. 2006;34(6):1589-96.15 Total patients (%) Patient survival rate (%) 100 Patients with e ective antibiotic therapy 80 60 40 20 0 0 hours 1 2 3 4 5 6 9 12 24 36 Time to antibiotics 3 When should a blood culture be performed? Blood cultures should always be requested when a bloodstream infection or sepsis is suspected. v C linical symptoms in a patient which may lead to a suspicion of a bloodstream infection are: undetermined fever (≥38°C) or hypothermia (≤36°C) shock, chills, rigors s evere local infections (meningitis, endocarditis, pneumonia, pyelonephritis, intra-abdominal suppuration…). abnormally raised heart rate low or raised blood pressure raised respiratory rate 5 BLOOD CULTURE ESSENTIALS v B lood cultures should be collected: as soon as possible after the onset of clinical symptoms; ideally, prior to the administration of antimicrobial therapy.16 If the patient is already on antimicrobial therapy, recovery of microorganisms may be increased by collecting the blood sample immediately before administering the next dose and by inoculating the blood into bottles containing specialized antimicrobial neutralization media. 4 W hat volume of blood should be collected? The optimal recovery of bacteria and fungi from blood depends on culturing an adequate volume of blood. The collection of a sufficient quantity of blood improves the detection of pathogenic bacteria or fungi present in low quantities. This is essential when an endovascular infection (such as endocarditis) is suspected. The volume of blood that is obtained for each blood culture set is the most significant variable in recovering microorganisms from patients with bloodstream infections.17, 18 Blood culture bottles are designed to accommodate the recommended bloodto-broth ratio (1:5 to 1:10) with optimal blood volume. Commercial continuously monitoring blood culture systems may use a smaller blood-to-broth ratio ( 200 4 2 6 12.8-36.3 28-80 > 800 10 10 20 > 36.3 > 80 > 2,200 20-30 20-30 40-60 % of patient’s total blood volume 4 4 3 2.5 1.8-2.7 7 BLOOD CULTURE ESSENTIALS 5 H ow many blood culture sets should be collected? Since bacteria and fungi may not be constantly present in the bloodstream, the sensitivity of a single blood culture set is limited. Using continuous-monitoring blood culture systems, a study investigated the cumulative sensitivity of blood cultures obtained sequentially over a 24-hour time period. It was observed that the cumulative yield of pathogens from three blood culture sets (2 bottles per set), with a blood volume of 20 ml in each set (10 ml per bottle), was 73.1% with the first set, 89.7% with the first two sets and 98.3% with the first three sets. However, to achieve a detection rate of > 99% of bloodstream infections, as many as four blood culture sets may be needed.22 Figure 2: Cumulative sensitivity of blood culture sets22 Adapted from Lee A, Mirrett S, Reller LB, Weinstein MP. Detection of Bloodstream Infections in Adults: How Many Blood Cultures Are Needed? J Clin Microbiol 2007;45:3546-3548. Detection sensitivity 100% 90% 89.7% 98.3% 80% 73.1% 70% 20 ml 40 ml 60 ml A single blood culture bottle or set should never be drawn from adult patients, since this practice will result in an inadequate volume of blood cultured and a substantial number of bacteremias may be missed.3, 22 8 BLOOD CULTURE ESSENTIALS A contaminant will usually be present in only one bottle of a set of blood culture bottles, in contrast to a true bloodstream infection, in which multiple blood culture bottles/sets will be positive. Therefore, guidelines recommend to collect 2, or preferably 3, blood culture sets for each septic episode.3, 7, 16 If 2 to 3 sets are taken and cultures are still negative after 24-48 hours incubation, and the patient is still potentially septic, 2 to 3 additional cultures may be collected, as indicated in the following diagram.16 Figure 3: Recommended number of blood culture sets Adapted from Baron EJ, Cumitech 1C, Blood Cultures IV. Coordinating ed., E.J. Baron. ASM Press, Washington, D.C. 2005 Collect 2 to 3 sets of bottles (aerobic + anaerobic) for each septic episode If culture is negative after 24-48 h incubation and patient is still potentially septic without an identified source Collect 2 to 3 additional sets of bottles (aerobic + anaerobic) If culture is negative after 24 h incubation Repeat protocol Prolong if necessary incubation Investigate non-microbial etiology 9 BLOOD CULTURE ESSENTIALS 6 W hich media to use? Microorganisms causing bloodstream infections are highly varied (aerobes, anaerobes, fungi, fastidious microorganisms…) and, in addition to nutrient elements, may require specific growth factors and/or a special atmosphere. In cases where the patient is receiving antimicrobial therapy, specialized media with antibiotic neutralization capabilities should be used. Antibiotic neutralization media have been shown to increase recovery and provide faster time to detection versus standard media.23-26 It is recommended that each adult routine blood culture set include paired aerobic and anaerobic blood culture bottles. The blood drawn should be divided equally between the aerobic and anaerobic bottles. If an anaerobic bottle is not used, it should always be replaced by an additional aerobic bottle to ensure that a sufficient volume of blood is cultured.27 v A blood culture medium must be: sensitive enough to recover: - a broad range of clinically relevant microorganisms, even the most fastidious (Neisseria, Haemophilus…) - microorganisms releasing small amounts of CO2 (Brucella, Acinetobacter…) versatile: able to provide a result for all types of sample collection (adults, infants, patients receiving antibiotic therapy, sterile body fluids…) v Which bottle should be inoculated first? If using a winged blood collection set, then the aerobic bottle should be filled first to prevent transfer of air in the device into the anaerobic bottle. If using a needle and syringe, inoculate the anaerobic bottle first to avoid entry of air. If the amount of blood drawn is less than the recommended volume*, then approximately 10 ml of blood should be inoculated into the aerobic bottle first, since most cases of bacteremia are caused by aerobic and facultative bacteria. In addition, pathogenic yeasts and strict aerobes (e.g., Pseudomonas) are recovered almost exclusively from aerobic bottles. Any remaining blood should then be inoculated into the anaerobic bottle.8 * For recommended volumes, see page 6 “What volume of blood should be collected? 10 BLOOD CULTURE ESSENTIALS 7 T iming of blood cultures Studies have shown that the time interval between collecting two blood culture samples is not considered to be a critical factor as the diagnostic yield remains the same.7 Guidelines recommend that the first two/three sets (2 bottles/set) of blood culture be obtained either at one time or over a brief time period (e.g., within 1 hour) from multiple venipuncture sites.1,16 Drawing blood at spaced intervals, such as 1 to 2 hours apart, is only recommended to monitor continuous bacteremia/fungemia in patients with suspected infective endocarditis or other endovascular (i.e., catheterrelated) infections.16 Two to three additional blood culture sets can be performed if the first 2-3 blood cultures are negative after 24-48 hours incubation in cases of severe infection or in order to increase detection sensitivity (in cases of pyelonephritis for example). This also depends on the microorganisms involved: while sensitivity is relatively good for organisms like Escherichia coli or Staphylococcus aureus, it is lower for Pseudomonas aeruginosa, streptococci or fungi.28 8 H ow to collect blood cultures Sample collection is a crucial step in the blood culture process. Standard precautions must be taken, and strict aseptic conditions observed throughout the procedure. Compliance with blood culture collection recommendations can significantly improve the quality and clinical value of blood culture investigations and reduce the incidence of sample contamination and “false-positive” readings. A properly collected sample, that is free of contaminants, is key to providing accurate and reliable blood culture results. It is recommended that blood cultures should be collected only by members of staff (medical, nursing, phlebotomist or technician) who have been fully trained and whose competence in blood culture collection has been assessed.29 11 BLOOD CULTURE ESSENTIALS 10 Key Steps to Good Sample Collection: For an illustrated step-by-step, see page 30. 1 Prior to use, examine the bottles for evidence of damage, deterioration or contamination. Do not use a bottle containing media which exhibits turbidity or excess gas pressure, as these are signs of possible contamination. 2 Check the expiry date printed on each bottle. Discard bottles that have expired. 3 S trictly follow the collection protocol in use in the healthcare setting, including standard precautions for handling blood at the bedside. 4 Blood culture bottles should be clearly and correctly labelled, including patient identification, date and collection time, puncture site (venipuncture or intravascular device). 5 E ach blood culture set should include an aerobic and an anaerobic bottle. 6 Blood for culture should be drawn from veins, not arteries.30 7 It is recommended to avoid drawing blood from a venous or arterial catheter, since these devices are often associated with higher contamination rates.31 12 BLOOD CULTURE ESSENTIALS 8 Carefully disinfect the skin prior to collection of the sample using an appropriate disinfectant, such as chlorhexidine in 70% isopropyl alcohol or tincture of iodine in swab or applicator form.1 9 Transport the inoculated bottles and the completed blood culture request to the clinical microbiology laboratory as quickly as possible, preferably within 2 hours per CLSI.1 Any delay in testing the inoculated bottles may potentially lead to an increased risk of false negative results. If delays are expected, it is important to refer to the manufacturer’s Instructions for Use (IFU) for guidance. As an example for guidance regarding delays, the ESCMID guidelines recommend that blood culture bottles for testing in continuous monitoring systems should be stored temporarily at room temperature, whereas bottles for manual testing should be incubated as soon as possible.32Again, refer to the manufacturer’s IFU for guidance. The use of vacuum tube transport systems can facilitate the rapid transmission of bottles to the microbiology laboratory. However these systems should be used with caution if using glass bottles.33 10 All blood cultures should be documented in the patient’s notes, including date, time, collection site and indications. 13 BLOOD CULTURE ESSENTIALS 9 H ow many days of incubation are recommended? The current recommendation, and standard incubation period, for routine blood cultures performed by continuous-monitoring blood systems is five days.34 However, published data suggest that three days may be adequate to recover over 97% of clinically significant microorganisms. A study by Bourbeau, et al. (JCM, 2005) showed the number of significant microorganisms isolated per day for 35,500 consecutive blood cultures collected over 30 months, of which 2,609 were clinically significant isolates and 1,097 were contaminants.35 Figure 4: Clinically significant isolates per day35 Adapted from Bourbeau PP, Foltzer M. Routine incubation of BACT/ALERT* FA and FN blood culture bottles for mo10re0t%han 3 days may not be necessary. J Clin Microbiol. 2005;43:2506-2509. 80% 74.1% 60% 40% 19.7% 20% 3.6% 1.7% 0.9% 0% Day 1 Day 2 Day 3 Day 4 Day 5 These results demonstrate that 97.4% of clinically significant isolates were recovered within the first 3 days of incubation and 93.8% within 2 days of incubation. v Incubation of Fastidious Microorganisms Another study by Cockerill, et al. (CID, 2004) demonstrated that, when using a continuous-monitoring blood culture system, 99.5% of non-endocarditis bloodstream infections and 100% of endocarditis episodes were detected within 5 days of incubation.19 This data suggests that extended incubation periods previously recommended for detection of the fastidious microorganisms* that sometimes cause endocarditis, are no longer necessary when using continuous-monitoring blood culture systems.16 * including Brucella, Capnocytophaga and Campylobacter spp., and the HACEK group (Haemophilus (except H. influenzae) species, Aggregatibacter (previously Actinobacillus) species, Cardiobacterium hominis, Eikenella corrodens and Kingella species)36 14 BLOOD CULTURE ESSENTIALS 10 I s it a contaminant or a true pathogen? Contamination of blood cultures during the collection process can produce a significant level of false-positive results, which can have a negative impact on patient outcome. A false positive is defined as growth of bacteria in the blood culture bottle that were not present in the patient’s bloodstream, and were most likely introduced during sample collection. Contamination can come from a number of sources: the patient’s skin, the equipment used to take the sample, the hands of the person taking the blood sample, or the environment. Collecting a contaminant-free blood sample is critical to providing a blood culture result that has clinical value. Certain microorganisms such as coagulase-negative staphylococci, viridansgroup streptococci, Bacillus spp, Propionibacterium spp., diphtheroids, Micrococcus spp. rarely cause severe bacterial infections or bloodstream infections. These are common skin contaminants, and a though they are capable of causing serious infection in the appropriate setting, their detection in a single blood culture set can reasonably be identified as a possible contaminant without clinical significance. However, it is important to consider that coagulase-negative staphylococci are the primary cause of both catheterand prosthetic device-associated infections and may be clinically significant in up to 20% of cases.37 The most difficult interpretation problem for the physician is whether the organism recovered from a blood culture is a true pathogen causing bloodstream infection, or a contaminant. If it is a contaminant, the patient may be treated unnecessarily with antibiotics, leading to additional patient risks. Interpretation of true pathogen versus contaminant should be based on whether the blood has been collected with a venipuncture or an intra-vascular device, and multiplicity of isolation of the same species. This illustrates the crucial nature of having collection site information included with the blood culture request sent to the laboratory. 15 BLOOD CULTURE ESSENTIALS In contrast to patients with infective endocarditis or other true positive bloodstream infections, patients whose blood cultures grow contaminants usually have only a single blood culture that is positive. This information is of great practical value for physicians, and underlines the importance of taking two to three blood culture sets from different anatomical sites.16 Contamination rates can be most effectively reduced by strict compliance with hand hygiene rules and best practices for blood collection, particularly during the stages of skin antisepsis, venipuncture and sample transfer to blood culture bottles. However, even when the best blood collection protocols are used, it may not be possible to reduce the contamination rate below 2%.38 The American Society for Microbiology and CLSI recommend targeting contamination rates not exceeding 3% of the total of collected sets.1, 16 v Impact of contamination rates A contaminated blood culture can result in unnecessary antibiotic therapy, increased length of hospitalization and higher costs. It has been found that each false positive result can lead to: Increased length of stay - on average 1 day.39 39% increase in intravenous antibiotic charges.39 $5,000 to $8,720 additional charges.40, 41 20% increase in laboratory charges.39 3 days longer on antibiotics.39 16 BLOOD CULTURE ESSENTIALS Figure 5: E xample of a laboratory-based algorithm to determine blood culture contamination42 Adapted from Richter SS, Beekman SE, Croco JL, Diekema DJ, et al. Minimizing the workup of blood culture contaminants: implementation and evaluation of a laboratory-based algorithm. J Clin Microbiol. 2002;40:2437-2444. Potential contaminant* isolated from blood culture Additional draws +/48 hours? NO YES Positive with same organism? NO YES Evaluation by qualified personnel Probable contaminant; AST** not performed unless requested Viridans group streptococci? NO YES Evaluation by qualified personnel Pathogen; set up AST† * Microorganisms such as coagulase-negative staphylococci, Streptococcus viridans, Bacillus spp, Propionibacterium spp., diphtheroids, Micrococcus spp. † AST: Antimicrobial Susceptibility Testing 17 2 SPECIAL TOPIC: INFECTIVE ENDOCARDITIS Blood culture is essential in the diagnosis of infective endocarditis (infection of the heart valves). In this elusive disease, blood cultures may need to be taken repeatedly during febrile episodes, when bacteria are shed from the heart valves into the bloodstream. For patients with infective endocarditis, positive blood cultures will be obtained in greater than 90% of cases, if optimal culture conditions are respected.43 v Acute Infective Endocarditis This is a fulminant illness progressing rapidly over days to weeks, which may be caused by highly virulent pathogens, such as Staphylococcus aureus. When suspected, the severity of this disease requires blood cultures to be drawn immediately to avoid unnecessary delays in treatment. Multiple blood culture sets should be drawn during a 30-minute period prior to administration of empiric antimicrobial therapy.44 v Subacute Infective Endocarditis If sub-acute infection is suspected, there is usually not an urgent need to initiate empiric therapy. It is more important to attempt to establish the microbiological diagnosis. Multiple blood culture sets should be obtained prior to initiation of antimicrobial therapy, with sets spaced 30 minutes to one hour apart. This may help document a continuous bacteremia, and could be of additional clinical value.3 v Fungal Infective Endocarditis Once a rare occurrence, the incidence of fungal endocarditis is increasing considerably.45 Candida species are the most common fungal pathogens involved in infective endocarditis.46 If optimum collection conditions are observed, the yield for positive blood cultures in fungal endocarditis for Candida spp. is 83 to 95%.47 18 SPECIAL TOPIC: INFECTIVE ENDOCARDITIS v How many cultures? In order to distinguish between contamination and true bacteremia, a total of three to five blood culture sets should be sufficient. Initially, two to three blood culture sets should be obtained from patients with suspected infective endocarditis. If the first 2-3 sets are negative after 24-48 hours, collect two to three more sets of cultures.3 Often patients with suspected infective endocarditis have been put on antibiotics prior to blood collection. This is the most common reason for “culture-negative” infective endocarditis. It is therefore important to use a blood culture medium that has antimicrobial neutralization capacity in order to sustain microbial growth in the presence of antibiotics (see page 10 “Which media to use?”).48,49 However, “culture-negative” endocarditis may also be due to fastidious microorganisms, such as Aspergillus spp., Brucella spp., Coxiella burnetii, Chlamydia spp. and HACEK* microorganisms. S ince current continuous-monitoring blood culture systems can recover all HACEK and other fastidious organisms within a 5-day period, extending incubation beyond this period is no longer considered to be necessary. However, if all blood culture bottles are negative after 5 days, and infectious endocarditis is still suspected, all bottles should be subcultured to chocolate agar.50 19 3 PROCESSING POSITIVE BLOOD CULTURES Today, continuously-monitored blood culture systems provide the optimum solution for blood sample processing. Generally accepted incubation periods can vary from 5-7 days, with 5 days being most popular.27 The study discussed in Figure 4 shows that 98% of all positive specimens were detected within the first 3 days (see page 14).35 Patients who progress to septic shock have a 7.6% increase in mortality every hour while not on appropriate therapy.15 Following an instrument-flagged positive event, the bottle is removed from the system and a Gram stain and subculture is performed. If the sample is Gram stain positive, the morphology of the organism should be reported immediately to the physician. Subcultures or rapid techniques (e.g., molecular diagnostics) should be initiated immediately in order to provide further organism identification and antibiotic susceptibility testing should be performed as soon as possible. If a sample is Gram stain negative, no report is made to the clinician unless there is growth on subculture. A positive blood culture is a critical result and must be reported as soon as available, due to the immediate impact on patient care decisions. When reports are delivered rapidly, studies have shown broadly improved outcomes and efficiencies in patient management.51, 52 A study by Barenfanger, et al. (Am J Clin Pathol. 2008) validated that Gram stains of positive blood cultures are a very important factor influencing appropriate therapy and patient outcomes. The study documented a statistically significant increase in the mortality rate for patients who had blood cultures processed after a delay (i.e., Gram stain performed ≥1 hour after being detected as positive; P= 0.0389). The timely removal and reporting of Gram stain results have a positive impact on patient care and this study supports the need for 24/7 coverage of blood culture instruments.53 20 PROCESSING POSITIVE BLOOD CULTURES Recent technological advances such as MALDI-TOF (Matrix-Assisted Laser Desorption Ionization Time of Flight) provide the ability to rapidly deliver definitive organism identification. Molecular diagnostics can identify the most common pathogens in positive blood cultures as well as specific antibiotic resistance genes associated with bloodstream infections. Rapid identification allows physicians to prescribe more targeted and effective antimicrobial therapy earlier to positively influence outcomes.54-56 Additionally, antibiotic susceptibility testing techniques should be performed on positive blood cultures to provide the clinician with a complete result. Appropriate use of antibiotics is crucial in cases of bloodstream infections and sepsis. Accurately determining the antimicrobial resistance profile of the causative pathogen in order to select the most effective antibiotic therapy can have a significant impact on patient outcomes. When processed correctly, blood cultures provide clinically relevant information that can help improve patient outcomes, decrease length of hospital stay and reduce use of antibiotics. 21 4 INTERPRETATION OF RESULTS The microbiology laboratory can provide useful information to clinicians to help them determine whether a blood culture sample is a true positive or a false positive (contaminant). For example, the identity of the micro- organism isolated can help determine if the culture is contaminated, and the number of Figure 6: Example of interpretation algorithm for blood culture results 1 More than one positive bottle monomicrobial culture + clinical symptoms (e.g., endocarditis, meningitis, pneumonia…) polymicrobial culture (from the appropriate clinical setting (e.g., transplants, intraabdominal infection, immunocompromized patient…) bloodstream infection probable bloodstream infection 3 Negative blood cultures but clinical symptoms 22 INTERPRETATION OF RESULTS cultures positive with the same organism can help predict true infections.57 Time to positivity is also a factor used to determine potential contamination as contaminants usually have a delayed (longer) time-to-detection due to a lower overall bio-load. Laboratories should consult with their medical director to create an algorithm which helps determine whether or not an isolated organism is a contaminant vs. an infective agent. Models, such as the algorithm below, can give guidance only on the interpretation of blood culture results.42, 57, 58 These guidelines should be used in conjunction with clinical guidelines e.g., patient’s full blood count, presence of catheters, radiological findings, etc. 2 Only one positive bottle if pathogenic organism: Listeria, S. aureus, Brucella, Haemophilus, Enterobacteriaceae, … if normal skin flora: Propionibacterium, corynebacterium, Bacillus, coagulase-negative staphylococci if viridans streptococci or coagulase-negative staphylococci and consistent with clinical setting (e.g., indwelling catheter, prosthetic heart valve, immunocompromized patient) probable bloodstream infection probable contamination probable bloodstream infection Repeat blood samples Consider non-infectious etiology Investigate viral etiology or non-culturable microorganism 23 5 BLOOD CULTURE/SEPSIS GUIDELINES v International Guidelines WHO guidelines on drawing blood: best practices in Phlebotomy. World Health Organization 2010. http://whqlibdoc.who.int/publications/2010/9789241599221_eng.pdf Surviving sepsis campaign: international guidelines for management of severe sepsis and septic shock: 2012. Dellinger RP., et al. Crit Care Med. 2013;41:580-637. http://www.survivingsepsis.org/guidelines/Pages/default.aspx The Third International Consensus Definitions for Sepsis and Septic Shock (Sepsis-3). Singer M., et al. JAMA. 2016;315(8):801-810. http://jama.jamanetwork.com/article.aspx?articleid=2492881 v National Guidelines COUNTRY/ REGION GUIDELINES Australia Clinical Excellence Commission. SEPSIS KILLS Adult Blood Culture Guideline Updated September 2016. SHPN (CEC) 160406. http://www.cec.health.nsw.gov.au/__data/assets/pdf_ file/0005/259412/adult-blood-culture-guideline-updated-sept2016.pdf Brazil Elmor de Araujo MR, Hemocultura: recomendações de coleta, processamento e interpretação dos resultados, J Infect Control 2012; 1: 08-19 http://www.iqg.com.br/pbsp/img_up/01355393320.pdf Europe European Society for Clinical Microbiology and Infectious Diseases, European Manual for Clinical Microbiology, 1st Edition, 2012. https://www.escmid.org/escmid_publications/manual_of_microbiology/ 24 BLOOD CULTURE/SEPSIS GUIDELINES COUNTRY/ REGION France GUIDELINES REMIC 2015. Automatisation des cultures microbiennes : quel cahier des charges ? Chapitre 11 http://www.sfm-microbiologie.org/ Germany Reinhart K, Brunkhorst FM, Bone HG, Bardutzky J, et al., Prevention, diagnosis, therapy and follow-up care of sepsis: 1st revision of S-2k guidelines of the German Sepsis Society (Deutsche Sepsis-Gesellschaft e.V. (DSG)) and the German Interdisciplinary Association of Intensive Care and Emergency Medicine (DIVI). German Medical Science, 2010, Vol. 8: 1-86 http://www.ncbi.nlm.nih.gov/pmc/articles/PMC2899863/pdf/ GMS-08-14.pdf South Africa Guideline for the optimal use of blood cultures. SAMJ 2010; Vol. 100, No. 12: 839-843 SAMJ https://www.fidssa.co.za/Content/Documents/Guideline_for_the_optimal_use_of_blood_cultures.pdf UK UK Standards for Microbiology Investigations. Investigation of Blood Cultures (for Organisms other than Mycobacte- rium species). Bacteriology | B 37 | Issue no: 8 | Issue date: 04.11.14 | Page: 1 of 51. Issued by the Standards Unit, Health Protection Agency, PHE. https://assets.publishing.service.gov.uk/government/uploads/sys- tem/uploads/attachment_data/file/372070/B_37i8.pdf Taking blood cultures - a summary of best practice: Saving lives reducing infection, delivering clean and safe care. London: Department of Health; 2007. http://webarchive.nationalarchives.gov.uk/20120118171812/http://hcai. dh.gov.uk/files/2011/03/Document_Blood_culture_FINAL_100826.pdf USA American Society for Microbiology: Cumitech 1C, 2005 (EJ Baron et al.) ASM Press Clinical and Laboratory Standards Institute (CLSI®), document M47-A, Vol 27, 2007 (ML Wilson et al.) E mergency Nurses Association (ENA). Clinical Practice Guideline: Prevention of Blood Culture Contamination https://www.ena.org/docs/default-source/resource-library/practice-resources/cpg/bcccpg2c37f1815b664d2fa8d7e9fd0f475a41.pdf E .Septimus.CDCClinicianGuideforCollectingCultures.2015 https://www.cdc.gov/antibiotic-use/healthcare/implementation/clinicianguide.html 25 REFERENCES 1. P rinciples and procedures for Blood Cultures; Approved Guideline, CLSI document M47-A. Clinical and Laboratory Standards Institute (CLSI); Wayne, P.A. 2007 2. Adhikari NK, Fowler RA, Bhagwanjee S, Rubenfeld GD. Critical care and the global burden of critical illness in adults. Lancet 2010;376(9749):1339–1346. 3. WSD fact sheet 2013. www.world-sepsis-day.org 4. Kumar A, Ellis P, Arabi Y, et al. Initiation of inappropriate antimicrobial therapy results in a fivefold reduction of survival in human septic shock. Chest. 2009;136(5):1237-1248. 5. Singer M, Deutschmann CS, Seymour CW, et al. The Third International Consensus Definitions for Sepsis and Septic Shock (Sepsis-3). JAMA. 2016;315(8):801-810. 6. Koneman EW. Color Atlas and Textbook of Diagnostic Microbiology. Third Edition. 7. European Society for Clinical Microbiology and Infectious Diseases, European Manual for Clinical Microbiology, 1st Edition, 2012 8. Garey KW, Rege M, Pai MP, Mingo DE, et al. Time to Initiation of Fluconazole Therapy Impacts Mortality in Patients with Candidemia: A Multi-Institutional Study. Clin Infect Dis. 2006;43(1):25-31. 9. Khatib R, Saeed S, Sharma M, Riederer K, Fakih MG, Johnson LB. Impact of initial antibiotic choice and delayed appropriate treatment on the outcome of Staphylococcus aureus bacteremia. Eur J Clin Microbial Infect Dis. 2006; 25(3):181185. 10. K ollef MH, Sherman G, Ward S, Fraser VJ. Inadequate antimicrobial treatment of infections: a risk factor for hospital mortality among critically ill patients. Chest. 1999;115(2):462-474. 11. H arbarth S, Garbino J, Pugin J, Romand JA, Lew D, Pittet D. Inappropriate initial antimicrobial therapy and its effect on survival in a clinical trial of immunomodulating therapy for severe sepsis. Am J Med. 2003;115(7):529-535. 12. Lodise TP, McKinnon PS, Swiderski L, Rybak MJ. Outcomes analysis of Delayed Antibiotic Treatment for Hospital-Acquired Staphylococcus aureus Bacteremia. CID 2003;36:1419-1423. 13. Kang CL, Kim SH, Kim HB, et al. Pseudomonas aeruginosa bacteremia: risk factors for mortality and influence of delayed receipt of effective antimicrobial therapy on clinical outcome. Clin Infect Dis. 2003; 37(6): 745-51 14. Forrest GN, Mankes K, Jabra-Rizk MA, et al. Peptide Nucleic Acid Fluorescence In Situ Hybridization Based Identification of Candida albicans and Its Impact on Mortality and Antifungal Therapy Costs. J Clin Microbiol. 2006;44(9):3381-3383. 26 15. Kumar A, Roberts D, Wood KE, et al. Duration of hypotension before initiation of effective antimicrobial therapy is the critical determinant of survival in human septic shock. Crit Care Med. 2006;34(6):1589-1596. 16. B aron EJ, Weinstein MP, Dunne Jr. WM, Yagupsky P, Welch DF, Wilson DM. Cumitech 1C, Blood Cultures IV. Coordinating ed., E.J. Baron. ASM Press, Washington D.C. 2005. 17. M ermel LA, Maki DG. Detection of bacteremia in adults: consequences of culturing an inadequate volume of blood. Ann Intern Med. 1993;119:270-272. 18. Bouza E, Sousa D, Rodriguez-Creixems M, Lechuz JG, Munoz P. Is the volume of blood cultured still a significant factor in the diagnosis of bloodstream infections? J Clin Microbiol. 2007 45:2765-2769. 19. Cockerill FR 3rd, Wilson JW, Vetter EA, et al. Optimal testing parameters for blood cultures. Clin Infect Dis. 2004;38:1724-1730. 20. K ellog JA, Manzella JP, Bankert DA. Frequency of low-level bacteremia in children from birth to fifteen years of age. J Clin Microbiol. 2000;38:2181-2185. 21. Freedman SB, Roosevelt GE. Utility of anaerobic blood cultures in a pediatric emergency department. Pediatr Emerg Care. 2004;20(7):433-436. 22. Lee A, Mirrett S, Reller LB, Weinstein MP. Detection of Bloodstream Infections in Adults: How Many Blood Cultures Are Needed? J Clin Microbiol. 2007;45:3546-3548. 23. Lee DH, Kim SC, Bae IG, Koh EH, Kim S. Clinical Evaluation of BACT/ALERT FA Plus and FN Plus Bottles Compared with Standard Bottles. J Clin Microbiol. 2013;51(12):4150-4155. 24. Amarsy-Guerle R, Mougari F, Jacquier H, et al. High medical impact of implementing the new polymeric bead-based BACT/ALERT FA Plus and FN Plus blood culture bottles in standard care. Eur J Clin Microbiol Dis. 2015:34(5):1031-1037. 25. Kirn TJ, Mirrett S, Reller LB, Weinstein MP. Controlled Clinical Comparison of BACT/ ALERT FA Plus and FN Plus Blood Culture Media with BACT/ALERT FA and FN Blood Culture Media. J Clin Microbiol. 2014;52(3):839-843. 26. Doern CD, Mirrett S, Halstead D, Abid J, Okada P, Reller LB. Controlled Clinical Comparison of New Pediatric Medium with Adsorbent Polymeric Beads (PF Plus) versus Charcoal-Containing PF Medium in the BACT/ALERT Blood Culture System. J Clin Microbiol. 2014;52(6):1898-1900. 27. R iley JA, Heiter BJ, Bourbeau PP. Comparison of recovery of blood culture isolates from two BACT/ALERT FAN aerobic blood culture bottles with recovery from one FAN aerobic bottle and one FAN anaerobic bottle. J Clin Microbiol. 2003;41:213-217. 27 REFERENCES 28. W einstein MP,Towns ML, Quartey SM, et al. The clinical significance of positive blood cultures in the 1990s; a prospective comprehensive evaluation of the microbiology, epidemiology, and outcome of bacteremia and fungemia in adults. Clin Infect Dis. 1997;24:584-602. 29. U K Department of Health: Taking Blood Cultures – A summary of best practice. 2007 30. W einstein MP. Current blood culture methods and systems: clinical concepts, technology, and interpretation of results. Clin Infect Dis. 1996;23:40-46. 31. E verts RJ, Vinson EN, Aholla PO, Reller LB. Contamination of catheter-drawn blood cultures. J Clin Microbiol. 2001;39:3393-3394. 32. Cornaglia G, Courcol R, Hermann JL, Kahlmeter G. European Manual of Microbiology. ESCMID-SFM 2012. 33. K irm TJ, Weinstein MP. Update on blood cultures: how to obtain, process, report, and interpret. Clin Microbiol Infect. 2013;19(6):513-520. 34. W ilson ML, Mirrett S, Reller LB, Weinstein MP, Reimer LG. Recovery of clinically important microorganisms from the BACT/ALERT blood culture system does not require testing for 7 days. Diagn Microbiol Infect Dis. 1993;16:31-34. 35. Bourbeau PP, Foltzer M. Routine Incubation of BACT/ALERT FA and FN blood culture for more than 3 days may not be necessary. J Clin Microbiol. 2005;43:2506-2509. 36. S chlossberg D, ed. Clinical Infectious Disease. Cambridge University Press, 2015. 37. Hall KK, Lyman JA. Updated Review of Blood Culture Contamination. Clin Microbiol Rev. 2006,19(4):788. 38. D unne Jr. WM, Nolte FS, Wilson ML. Cumitech 1B, Blood Cultures III. coordinating ed. Hindler JA. ASM Press. Washington, D.C. 1997. 39. Hall KK, Lyman JA. Updated review of blood culture contamination. Clinical Microbiology Reviews. 2006;19:788-802. 40. Bamber AI, Cunniffe JG, Nayar D, Ganguly R, Falconer E. The effectiveness of introducing blood culture collection packs to reduce contamination. Br J Biomed Sci. 2009;66(1):1-9. 41. Gander RM, Byrd L, DeCrescenzo, Hirany S, Bowen M, Baughman J. Impact of Blood Cultures Drawn by Phlebotomy on Contamination Rates and Health Care Costs in a Hospital Emergency Department. J Clin Microbiol. 2009;47:1021-1024. 42. Richter SS, Beekman SE, Croco DJ, et al. Minimizing the workup of blood culture contaminants: implementation and evaluation of a laboratory-based algorithm. J Clin Microbiol. 2002;40:2437-2444. 43.T owns ML, Reller LB. Diagnostic methods: current best practices and guidelines for isolation of bacteria and fungi in infective endocarditis. Infect Dis Clin N Am. 2002;16:363-376. 44. Osborn TM, Nguyen HB, Rivers EP. Emergency medicine and the surviving sepsis campaign: an international approach to managing severe sepsis and septic shock. Ann Emerg Med. 2005;46:228-231. 45. R ubenstein E, Lang R. Fungal endocarditis. Eur Heart J. 1995:16(Suppl B):84-89. 46. E llis ME,Al-Abdely H, Sandridge A, Greer W,Ventura W. Fungal endocarditis: evidence in the world literature, 1965-1995. Clin Infect Dis. 2001; 32:50-62. 28 REFERENCES 47. M cLeod R., Remington JS. Fungal endocarditis. In: Rahimtoola SH et al., eds. Infective Endocarditis. New York, NY: Gune & Stratton.1978:211-290 48. Z iegler R, Johnscher I, Martus P, Lenhardt D, Just HM. Controlled Clinical Laboratory Comparison of Two Supplemented Aerobic and Anaerobic Media Used in Automated Blood Culture Systems to Detect Bloodstream Infections. J Clin Microbiol. 1998;36:657-661. 49. Pohlman JK, Kirkley BA, Easley KA, Basille BA, Washington JA. Controlled Clinical Evaluation of BACTEC Plus Aerobic/F and BACT/ALERT Aerobic FAN Bottles for Detection of Bloodstream Infections. J Clin Microbiol. 1995;33:2856-2858. 50. B aron EJ, Scott JD,Tompkins LS. Prolonged incubation and extensive subculturing do not increase recovery of clinically significant microorganisms from standard automated blood cultures. Clin Infect Dis. 2005;41:1677-1680. 51. Beekmann SE, Diekema DJ, Chapin KC, Doern GV. Effects of rapid detection of bloodstream infections on length of hospitalization and hospital charges. J Clin Microbiol. 2003;41:3119-3125. 52. Munson EL, Diekema DJ, Beekmann SE, Chapin KC, Doern GV. Detection and treatment of bloodstream infection: laboratory reporting and antimicrobial management. J Clin Microbiol. 2003;41:495-497. 53. B arenfanger J, Graham DR, Kolluri L, et al. Decreased Mortality Associated With Prompt Gram Staining of Blood Cultures. Am J Clin Pathol. 2008;130:870-876. 54. Timbrook T, Boger MS, Steed LL, Hurst JM. Unanticipated Multiplex PCR Identification of Polymicrobial Blood Culture Resulting in Earlier Isolation, Susceptibilities, and Optimization of Clinical Care. J Clin Microbiol. 2015;53(7):2371-2373. 55. Bauer KA, West JE, Balada-Llasat JM, Pancholi P, Stevenson KB, Goff DA. An Antimicrobial Stewardship Program’s Impact with Rapid Polymerase Chain Reaction Methicillin-Resistant Staphylococcus aureus/S. aureus Blood Culture Test in Patients with S. aureus Bacteremia. Clin Infect Dis. 2010;51(9):1074-1080. 56. Dierkes C, Ehrenstein B, Siebig S, Linde HJ, Reischl U, Salzberger B. Clinical impact of a commercially available multiplex PCR system for rapid detection of pathogens in patients with presumed sepsis. BMC Infect Dis. 2009; 9(1):126 57. Weinstein MP. Blood Culture Contamination: Persisting Problems and Partial Progress. J Clin Microbiol. 2003;41:2275-2278. 58. Weinstein MP, Towns ML Quartey SM, et al. The clinical significance of positive blood cultures in the 1990s: a prospective comprehensive evaluation of the microbiology, epidemiology and outcome of bacteremia and fungemia in adults. Clin Infect Dis. 1997;24:584-602. 59. Ernst DJ. Applied Phlebotomy. Dennis J. Ernst (MT(ASCP)). Lippincott Williams & Wilkins, 2005. 60. Lieseke CL, Zeibig EA. Essentials of Medical Laboratory Practice. F.A. Davis, 2012. 61. Q amruddin A, Khanna N, Orr D. Peripheral blood culture contamination in adults and venipuncture technique: prospective cohort study. J Clin Pathol. 2008;61:509513. 29 RECOMMENDATIONS FOR BLOOD CULTURE COLLECTION A) USING WINGED BLOOD COLLECTION SET (preferred method of collection)59-61 1 PREPARE BLOOD COLLECTION KIT Confirm the patient’s identity and gather all required materials before beginning the collection process. Do not use blood culture bottles beyond their expiration date, or bottles which show signs of damage, deterioration or contamination. It is recommended to identify the Fill-to Mark or mark the target fill level on the blood culture bottle label about 10 ml above the media level. 2 PREPARE BOTTLES FOR INOCULATION Wash hands with soap and water then dry, or apply an alcohol hand rub or another recognized effective hand rub solution. Remove the plastic “flip-cap” from the blood culture bottles and disinfect the septum using an appropriate and recognized effective disinfectant, such as chlorhexidine in 70% isopropyl alcohol, 70% isopropyl alcohol, or tincture of iodine in swab or applicator form. Use a fresh swab/applicator for each bottle. Allow bottle tops to dry in order to fully disinfect. 30 3 PREPARE VENIPUNCTURE SITE If skin is visibly soiled, clean with soap and water. Apply a disposable tourniquet and palpate for a vein. Apply clean examination gloves (sterile gloves are not necessary). Cleanse the skin using an appropriate disinfectant, such as chlorhexidine in 70% isopropyl alcohol or tincture of iodine in swab or applicator form. The venipuncture site is not fully clean until the disinfectant has fully evaporated. 6 OTHER BLOOD TESTS If blood is being collected for other tests, an insert placed into the adapter cap may be required. The insert is used to guide blood collection tubes onto the needle. If other blood tests are requested, always collect the blood culture first. 4 VENIPUNCTURE Attach a winged blood collection set to a collection adapter cap.* To prevent contaminating the puncture site, do not re-palpate the prepared vein before inserting the needle. Insert the needle into the prepared vein. 5 CULTURE BOTTLE INOCULATION Place the adapter cap over the aerobic bottle and press straight down to pierce the septum. Hold the bottle upright, below the level of the draw site, and add up to 10 ml of blood per adult bottle and up to 4 ml per pediatric bottle.† Ensure the bottle is correctly filled to the Fill-to Mark or target fill level. Once the aerobic bottle has been inoculated, repeat the procedure for the anaerobic bottle. 7 FINISH THE PROCEDURE Discard the winged collection set into a sharps container and cover the puncture site with an appropriate dressing. Remove gloves and wash hands before recording the procedure, including indication for culture, date, time, site of venipuncture, and any complications. Ensure additional labels are placed in the space provided on the bottle label and do not cover the bottle barcodes, and that the tear-off barcode labels are not removed. If additional labels contain a barcode, they should be positioned in the same manner as the bottle barcode. Inoculated bottl
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