NOTICES
DEPARTMENT OF HEALTH
Newborn Screening Specimen Collection Standards
[32 Pa.B. 2724] Under 28 Pa. Code § 28.21(d) (relating to responsibility for collecting and testing initial and repeat specimens), the Department of Health hereby publishes the following techniques for blood collection on filter paper as developed by the National Committee for Clinical Laboratory Standards (NCCLS) (NCCLS VOL. 17, No. 16, Oct. 1997)
3 Techniques for Blood Collection on Filter Paper
3.1 Heelstick
3.1.1 Preliminary Steps
The required information on the specimen collection kit (card) must be completed either manually or electronically. In manual applications, a ballpoint pen should be used; soft-tip pens will not copy through to the other sheets of paper. Address imprint devices should be carefully used so that imprinted data do not obscure pertinent patient information and handling does not compromise the blood collection data. A typewriter should not be used. Before and during collection of the specimen, touching the area within the circles on the filter paper section must be avoided. After the specimen has been collected, the blood spots should not be touched. Water, feeding formulas, antiseptic solutions, glove powder of other materials should not be allowed to come into contact with the specimen card before or after use.
3.1.2 Precautions
Confirm the identity of the infant and ensure linkage with the demographic data on the card. Wash hands vigorously before proceeding. All other appropriate precautions, including wearing powder-free gloves (changing gloves between infants), should be taken for handling blood and disposing of used lancets in a biohazard container for sharp objects. (See the most current version of NCCLS document M29--Protection of Laboratory Workers from Infectious Disease Transmitted by Blood, Body Fluids, and Tissue.)
3.1.3 Site Preparation
Warming the skin-puncture site can increase blood flow. A warm, moist towel or diaper at a temperature no higher than 42°C may be used to cover the site for 3 minutes. Acceptable heel warming devices are also commercially available. This technique increases the blood flow sufficiently and will not burn the skin. In addition, positioning the infant's leg lower than the heart will increase venous pressure. (Caution: Before topical anesthetic creams are used to reduce the pain of a heel puncture, the screening laboratory should document that these creams do not produce analytic interferences.)
3.1.4 Cleaning the Site
The skin should be wiped with alcohol (isopropanol/water: 70/30 by volume, 70%). Allow the skin to air-dry. Alcohol residue remaining on the skin may dilute the specimen and adversely affect test results.
3.1.5 Puncture
To obtain sufficient blood flow, the infant's heel should be punctured with a sterile lancet to a depth of approximately 2.0 mm (see Table 1 in Reference 4 for lancet size) or with an automated lancet device, on the plantar surface of the heel (See the most recent edition of NCCLS document H4--Procedures for the Collection of Diagnostic Blood Specimens by Skin Puncture.) Scalpel blades must not be used to puncture the skin for blood collection. The first drop of blood should be wiped away with sterile gauze.
Disposable skin puncture lancets of different designs are commercially available for performing the heel stick on infants. For worker safety, disposable skin puncture devices that protect the user from unintentional self-inflicted skin punctures are also available. In small premature infants, the heel bone (calcaneus) may be no more than 2.0 mm beneath the plantar heel skin surface and half this depth at the posterior curvature of the heel. Puncturing deeper than 2.0 mm on the plantar surface of the heel on small infants may, therefore, cause bone damage. Studies indicate that for some infants (including premature infants) a puncturing depth beyond 2.0 mm may be extensive; this issue needs further study.
3.1.6 Direct Application
After the heel puncture, the first drop of blood should be wiped away and a large drop of blood allowed to form. Apply gentle pressure with the thumb and ease intermittently as drops of blood form. (See Section 3.1.6.1.) The filter paper should be touched gently against the large blood drop and, in one step, a sufficient quantity of blood allowed to soak through to completely fill a preprinted circle (Section 5.1 [11]) on the filter paper. The paper must not be pressed against the puncture site on the heel. Blood should be applied only to one side of the filter paper. Both sides of the filter paper should be examined to assure that the blood uniformly penetrated and saturated the paper. After blood has been collected from the heel of the newborn, the foot should be elevated above the body and a sterile gauze pad or cotton swab pressed against the puncture site until the bleeding stops. It is not advisable to apply adhesive bandages over skin puncture sites on newborns. (For treatment of the puncture site after specimen collection, see the current edition of NCCLS document H4).
3.1.6.1 Milking
Milking or squeezing the puncture may cause hemolysis of the specimen or result in an admixture of tissue fluids with the specimen. These outcomes can invalidate an analytic test result.
3.1.6.2 Layering
Layering or application of successive drops of blood to the same printed circle causes caking and/or nonuniform concentrations of blood. If blood flow diminishes so that circles are not completely filled, repeat the sampling technique in a new circle. (See Sections 3.1.3--3.1.6).
3.1.7 Collection
The required number of blood spots should be collected. Failure to collect the appropriate number of spots may invalidate the specimen for all tests depending on screening program rules. (See Section 1.2.)
3.1.8 Drying
Touching or smearing the blood spots must be avoided. The blood specimen should be allowed to air-dry on a horizontally level, nonabsorbent open surface for at least 3 hours at ambient temperature (15°C to 22°C) and away from direct sunlight (indirect room light is not usually detrimental). Blood spots on the filter paper should not be heated, stacked or allowed to touch other surfaces during the drying process.
3.1.9 Stacking
When batch stacking of exposed dried blood spots cannot be avoided, the following procedure should be used. Before placing the specimens in a container for transport, the dried blood spots on the collection card should be rotated 180° from the blood spots on the cards in the stack immediately above and below unless the specimens are separated by other physical barriers, for example, fold-over-paper covers, glassine paper. (See Section 4.4.2.)
3.1.10 Transport (Mailing)
Unless otherwise directed by the screening laboratory, the collection card should be transported or mailed to the laboratory within 24 hours after collecting the specimen and the appropriate tracking documentation maintained. Delays at collection sites should be avoided, and the shipping environment relative to possible delays should be structured to maximize transport efficiency. (See Section 4.4.1.)
3.1.11 Storage
If residual dried blood spot specimens are to be stored by the laboratory for extended periods, they must be protected to ensure noncompromised status after storage. One method is to store the specimens in low gas-permeable, zip-closure plastic bags with desiccant and humidity indicator cards. Humidity should be maintained below 30%. Positive and negative blood spot controls, if available, should be stored with the residual specimens so that the specimen's integrity can be checked when it is removed from storage. (See Section 6.0 for precautions if DNA analysis is anticipated.)
3.2 Capillary Tube
Although not the preferred method, applying blood collected in sterile heparinized capillary tubes (see NCCLS document H4) onto the preprinted circles of the filter paper is an acceptable alternative to applying the blood directly from the heel puncture site. (See Sections 3.1.1--3.1.5 for heel puncture.) The capillary tube method also applies to any cord blood application onto filter paper. Consult appropriate local regulations and institutional policies for specific applications.
3.2.1 Collection
The tip of the heparinized capillary tube should be touched to the blood drop formed at the heel puncture site. (See Section 3.1.5.) Blood will flow into the tube by capillary action. Improved tube fill rates may be achieved when the tube is held in a near horizontal position to the blood drop.
Approximately 100uL of blood (See Section 5.1 [11]) should be collected into the heparinized capillary tube, using a fresh capillary tube for each blood spot that will be collected on the filter paper.
3.2.2 Application
After filling each capillary tube (75-uL or 100-uL size) to the calibration mark, the contents of the tubes should be immediately applied to the center of a single preprinted circle on the filter paper to fill the preprinted circle completely. Waiting too long before application will allow cells and plasma to separate. Actions such as ''coloring in'' the circle, repeated dabbing around the circle or any technique that might scratch, compress or indent the paper should not be used.
The blood should be applied to only one side of the filter paper. Multiple applications should not be used; caking or heterogeneous spreading will occur and may adversely affect test results. The directions in Sections 3.1.7--3.1.11 should be followed to complete the procedure.
3.3 Dorsal Hand Vein
Although not the method of choice, blood collected from needle puncture of the dorsal hand vein and its application directly onto the preprinted circles of the filter paper is an acceptable alternative to direct application from the heel puncture site. (For extensive details of this technique and application methods, see M. E. Clagg in Laboratory Medicine [1989;20: 248-250]). After venipuncture, the procedures outlined in Sections 3.1.6 and 3.1.11 for blood collection on filter paper should be followed. In some situations the hand veins may be needed for intravenous fluid (IV) use and should be avoided for specimen collection. Blood should not be drawn from an extremity (hand) into which IV fluids, including blood, are being or have been infused. Consult appropriate local regulations and institutional policies for specific applications.
Precaution: Syringe collection of blood for application onto a collection device (card) is not recommended because of lack of anticoagulant and time delays that could allow for clot formation and settling of cells producing heterogeneous specimens.
Some differences in the analyte concentration in skin puncture blood and venous blood have been reported and the clinical importance of this difference for neonatal screening test outcomes must be quantitatively assessed before use of dried venous blood spots for the specific analytes of interest. Precaution: Statistically and/or clinically important differences in the concentrations of analytes (for example, phenylalanine) important to newborn screening have been reported.
For additional information, contact the Division of Newborn Disease Prevention and Identification, (717) 783-8143.
Persons with a disability who desire a copy of the standards in an alternative format (for example, large print, audiotape or Braille) should notify the Division of Newborn Disease Prevention and Identification at (717) 783-8143; V/TT (717) 783-6514 for speech and/or hearing impaired persons or the Pennsylvania AT&T Relay Services at (800) 654-5984 [TT].
ROBERT S. ZIMMERMAN, Jr.,
Secretary
[Pa.B. Doc. No. 02-961. Filed for public inspection May 31, 2002, 9:00 a.m.]
No part of the information on this site may be reproduced for profit or sold for profit.This material has been drawn directly from the official Pennsylvania Bulletin full text database. Due to the limitations of HTML or differences in display capabilities of different browsers, this version may differ slightly from the official printed version.
