Automation technology promotes safe handling and processing of blood.

Safety has been a constant concern in clinical laboratories, but hematology is an area of particular caution because blood-borne pathogens cause fear. At times, this is a rational worry; blood, after all, can transmit several common but serious diseases under certain circumstances. Sometimes the fear of becoming contaminated through blood handling is less firmly based in reality, however. A number of high-profile incidents that resulted in the severe illness or death of laboratory workers inspired a degree of panic when they became news items, despite the fact that they usually involved routes of transmission other than blood.

Most of these infections were acquired in research settings, not clinical laboratories, by staff working with unusually infectious materials and/or unpredictable animal subjects. For example, the victims who died of laboratory-acquired Marburg virus in 1967 and smallpox in 1978 were not handling blood in clinical laboratories, but their stories have had direct consequences for the technology used in those laboratories ever since, driving innovation toward safer practices.

Of course, the clinical laboratory’s staff must be protected from genuine risk. Given the competition that many laboratories face for too-scarce personnel, the wise laboratory will also be sure that even the perception of high risk is eliminated. By calming the small percentage of potential employees who may be skittish about working with blood, the laboratory’s investment in technology that promotes safety will contribute to the facility’s ability to hire and retain staff. By showing that it cares about their well-being and comfort, the laboratory will simultaneously impress a much larger segment of workers.

Three Ways to Address Safety

Manufacturers of hematology equipment and supplies use three strategies to help laboratories address safety issues (both real and perceived):

  1. The first is simply to remove staff from as many operations involving blood as possible through the automation of hematology tasks, since risk does not exist wherever robots and automated instruments replace humans in the chain of testing activities.
  2. The second strategy is to reduce risk by making typical accidents themselves less likely to happen; this can be particularly helpful in laboratories that are not fully automated. For example, the risks of handling specimens multiple times can be decreased by using multipurpose instruments that provide several testing results with only a single loading and/or retrieval step performed by staff. Ergonomically designed equipment can also decrease the risk of accident by simultaneously making the user’s actions less awkward and preventing the weakness that can result from repetitive stress. In addition, proper quality-control measures reduce risk by eliminating unnecessary repetition of tests.
  3. The third strategy is to control risk by reducing the likelihood of blood contact, even when an accident does occur. This is accomplished by making everyday laboratory materials (such as sampling tubes) stronger, more flexible, and less likely to spill or leak.

No laboratory would expose its staff to the risk of blood-borne illness in the course of daily routine, obviously. The risk of infection, therefore, is tied to the risk of an accident that places the worker in direct contact with blood. Reducing the risk of accidents is the purpose of improving safety in hematology.

If current trends in research and development continue, it will become easier to achieve a safe laboratory environment because instruments will be smaller, lighter, and more readily incorporated into automated systems.

More vigilance will be required outside the laboratory, however, because the trend toward producing smaller and lighter instruments also makes those instruments more likely to be distributed for point-of-care testing. When they are placed in physicians’ offices, in ambulatory care centers, and on inpatient floors, hematology instruments will make extra attention to risk reduction imperative.

Additional precautions will be needed if the various trends that favor combining hematology testing with blood chemistry, urinalysis, cerebrospinal-fluid testing, and other diagnostic work continue; the more steps that a process includes, the more the opportunity for an accident arises.

Reducing Exposure

One example of the kind of laboratory automation that can improve safety (in addition to productivity) is the Cell-Dyn Rubyâ„¢ automated hematology instrument from Abbott Diagnostics, Abbott Park, Ill. Introduced in 2006, this analyzer is intended to handle moderate procedural volumes. It performs complete blood counts (CBCs) using advanced laser optics to enhance efficiency and provide results rapidly.

The optical technology used by this system, called multiangle polarized scatter separation, or MAPPSâ„¢, differentiates cellular components using laser light. It then yields visual depictions of changes in the form of detailed diagrams for white blood cells, red blood cells, and platelets. The system requires only four reagents to perform testing and is operated using intuitive software. Training is supported by online tutorials, and other automated instruments in the Cell-Dyne family are available to handle higher procedural volumes and additional test types.

Beckman Coulter Inc, Brea, Calif, also offers a fully automated hematology system, the LH 780. This system is intended for high-volume settings and can analyze serous, synovial, and cerebrospinal fluids. Its automatic correction for interfering substances ensures accuracy. Proprietary AccuCount technology reduces false-positive results (and the follow-up testing that they entail), boosting productivity and decreasing costs.

Nucleated red blood cells are identified and counted automatically, without any need for additional reagents. This helps to minimize technologist involvement. User-defined rules can standardize processes across shifts while customizing them to suit the facility and its patient population. Bar code reading streamlines workflow, and an extended quality-control rules package is available to help the laboratory meet performance standards. Consumables used with this system are environmentally friendly, and reagents free of cyanide are available.

A third automated hematology system is designed for small spaces. In fact, the Micros 60 3-DIFF analyzer from Horiba ABX Diagnostics, Irvine, Calif, meets this need so well that it has been installed on the cruise ships of the Princess and Disney lines, with ports in Florida and California serving as in-service training centers for the ships’ medical personnel. Described by the manufacturer as the most compact automated hematology instrument, the system weighs 14 kg, and its longest side measures 42 cm. Even its sampling needs are small, with microsampling being sufficient for its eight or 18 testing parameters.

The system can use open or closed tubes and has a throughput of 60 or 55 samples per hour for them, respectively. Smart-card memory is optional for both patient and quality-control data. A bar code reader is another available option. Values outside normal limits and counting failures are flagged for human attention. The system has no compressor, so noise and maintenance are reduced and reliability is increased. Impedance technology and photometry are used to produce results for 16 CBC parameters and two research applications.

In July, Horiba will launch an updated version— Micros im2 — enhanced by a comprehensive middleware system that offers patient data management along with accession logs of unlimited patient storage. It will have EMR and LIS connectivity capability.

One of the most comprehensive automated hematology systems is the Advia 2120 from Siemens Medical Solutions Diagnostics, Tarrytown, NY. It performs all typical tests on blood and cerebrospinal fluid and has multiple features designed to minimize technologist involvement. Advanced cell separation and isovolumetric sphering remove cell shape as a variable, improving the reliability of results. A sheath/rinse reagent encases a single-cell sample stream for analysis using flow cytometry.

Intracellular hemoglobin concentration is indicated by the high-angle scattering of red laser light; low-angle scattering indicates cell volume. Both concentration and volume results are used to produce cytograms and erythrograms. In turn, this indication of minority red-cell populations helps in differentiating the various hemoglobinopathies (including iron-deficiency anemia and thalassemia).

Reducing Handling

The XE-2100 hematology analyzer from Sysmex America Inc, Mundelein, Ill, is described as the only system that offers complete, extended differential parameters (including nucleated red blood cells, immature granulocytes, hematopoietic progenitor cells, immature reticulocyte fraction, and immature platelet fraction). The XE-2100 technology reduces the need for manual white-cell differentials, platelet counts, or smear reviews by using a semiconductive laser, a cell-specific lyse, and fluorescent flow cytometry.

Other Methods of Blood Safety

Training is another strategy that laboratories can use to improve worker safety; because laboratory operations vary so much, it is important to ensure that every member of the staff is familiar with the possible risks posed by each test or procedure. This training should be undertaken after the employee has been given institution-specific basic information on general safety, reporting accidents, and obtaining follow-up care.

Because congested walkways and tight quarters increase the risk of accidents, laboratory layout (and even scheduling) should also be part of risk reduction. Combined with automation, minimal handling, and safer supplies, these methods should help the laboratory reassure its staff members of their safety, as well as of their value to their employer. Each time the laboratory considers acquiring, upgrading, or replacing a piece of hematology equipment, the decision should take safety into account. Laboratory personnel need not risk their own health in the course of helping patients improve theirs.

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This patented technology measures fluorescence after cells in suspension have been stained using Sysmex polymethine. The laser is used for dye activation, after which cell size can be measured as cells pass through a narrow opening and scatter light forward. Side-scattered light is used to measure internal cellular complexity, and fluorescent intensity indicates nucleic-acid content.

Quick Slide, from GG&B Co, Wichita Falls, Tex, offers a small, inexpensive slide stainer that has impressive capabilities. The QuickSlide Plus stainer is highly adaptable as a backup unit in large laboratories or as the primary stainer in smaller operations. The stainer takes up only about 900 cm2 of counter space and has low acquisition and operating costs. Single slides are stained in less than a minute using high-quality QS-29000 stain.

No prefixing is needed for blood smears, although it is required for bone marrow slides. An advanced microprocessor is complemented by an LCD display with operator prompts. To ensure consistent results across multiple users, stain and buffer timing are adjustable, as is fill level. The computer monitors reagent levels and prompts the user to reorder them at the right time, in addition to displaying the number of cycles remaining. Reagent kits come in self-contained packages of 125 tests.

The model 7150 Aerospray® hematology slide stainer/cytocentrifuge from Wescor, Logan, Utah, adds the ability to perform cytocentrifugation of bodily fluids to its staining functions for blood and bone marrow smears. It has three built-in staining programs lasting 3 to 17 minutes, but is also fully programmable to accommodate custom staining. The optional Cytopro rotor turns it into a centrifuge with a capacity of eight slides.

The stainer uses a mixing process that produces more stable, partially aqueous stains. Reagents are mixed and applied as sprays by the system; because the reagent is applied according to the number of slides being stained, reagent waste is minimized and reagent costs are kept low, and mixing before application produces superior results. Up to 120 slides per hour can be processed.

Leica Microsystems Inc, Bannockburn, Ill, manufactures a clinical and research hematology microscope that promotes ergonomic use. The Leica DM1000 is used in all laboratory activities, but is especially helpful in the areas that can involve long viewing times per specimen and/or per day: hematology, pathology, and cytology. Its optical performance has been optimized, and its easy-to-use controls enhance user comfort.

It has focus knobs that are height adjustable, symmetrical and distortion-free operation of one-handed controls for stage and focus, a viewing angle of 15° with a standard tube, a color-coded aperture diaphragm, an x/y control that can be used by the right or left hand or eliminated, an ultrahard-ceramic stage surface, and a number of other features that are ergonomically correct and adjustable. Pathology-oriented imaging software is included, and the microscope has fluorescence capabilities.

Bio-Rad Laboratories, Hercules, Calif, makes the Liquichek™ Hematology-16 control for both cap-piercing and manual-sampling instruments measuring 16 or fewer parameters (along with three-part differentials for white blood cells). It uses stabilized human red blood cells and has been assayed on most instruments that measure 2 to 16 parameters. It has an open-vial stability of 21 days and a 160-day shelf life (for both, at storage temperatures of 2°C to 8°C). The parameters for which this control is suitable are granulocytes, % granulocytes, hematocrit, hemoglobin, lymphocytes, % lymphocytes, mean corpuscular hemoglobin, mean corpuscular hemoglobin concentration, mean corpuscular volume, mean platelet volume, monocytes, % monocytes, platelets, red blood cells, red-cell distribution width, and white blood cells.

The CVC 9005 hematocrit calibration verification control from RNA Medical, Devens, Mass, is made for use with the IRMA TRUpoint® blood-analysis systems using version 7.0 or higher of system software. CVC 9005 verifies the linearity, reportable range, and calibration of the hematocrit sensors. It comes in a ready-to-use, multilevel kit that provides information on the performance of the cartridges and the analyzers over their significant ranges. Data collection, graph generation, and reporting are simplified through the availability of online statistical analysis.

Another multilevel control kit is made by R&D Systems, Minneapolis. The CBC-Line ultralow-range linearity kit allows the performance of the hematology instrument to be measured at the lowest part of the linear range that can be reported accurately. The kit covers parameter determinations and reportable ranges for platelets and white blood cells. One computer-generated report is included in each kit of 3-mL vials, but extra reports can be bought.

Purchasers who establish standing orders for any hematology products from R&D Systems can enroll in the company’s CBC-Monitor program at no cost. This complete quality-control program for hematology uses state-of-the-art methods and can provide expert assistance to users with quality-control questions.

Reducing Harm

Manual operations can be optimized to promote staff safety in the absence of automated or minimal-handling equipment. Arkray USA, Edina, Minn, is an example of a company that uses precision and suitability for the task at hand to make manual products easier and safer to use. The company makes a number of ESR systems for use under specific circumstances, including pediatric and low-blood-volume applications.

For more information, search for “hematology” in our online archives.

The Streck Dispette is a triple-plugged pipette with a transparent reservoir that protects the user from exposure to blood overflows. Dispette 2 has prefilled (saline) reservoirs and caps that can be pierced to avoid spill hazards. The Sed-Pac® adds transfer pipettes to Dispette, and the Micro-Sed™ requires only 0.24 mL of blood. Winpetteâ„¢ needs 0.6 mL of blood for the Wintrobe ESR method. Vacupette™ minimizes handling by fitting pipettes with blood-displacement collection-tube adapters so that testing can be performed directly on citrated tubes.

Streck, Omaha, Neb, produces a line of erythrocyte sedimentation rate (ESR) tubes with a Mylar® coating on the exterior. Using this simple addition, Streck Safety Coated ESR-Vacuum Tubes make tube handling much safer for laboratory personnel. Even if an accident should cause the tube to break, the safety coating will hold the glass and blood inside it, not only preventing cuts but also the far more worrisome prospect of cuts coming in contact with the patient’s blood (and any pathogens it might contain).

The company reports that independent testing has indicated that the coated ESR tubes have ten times the impact resistance of ordinary glass tubes. To reduce the risk of overfilling or underfilling, Streck also makes its ESR-Vacuum line of tubes in versions for high and low elevations (altitudes). All of the tubes are used in the company’s automated ESR analyzers.

Kris Kyes is technical editor for  CLP.