Venipuncture Technique Using the Multisample Vacutainer System

Transcription

1 Venipuncture Technique Using the Multisample Vacutainer System Vacutainer Blood Collection The Vacutainer system General Instructions: Open needle package but do not remove needle shield. Thread needle onto holder. If drawing sterile sample, use sterile holder/needle combination. Select tube or tubes appropriate for samples desired. If a sterile specimen is required, use a sterile Vacutainer Tube. When collecting sterile samples, observe proper skin preparation directions. Tubes that contain additives should be gently tapped to dislodge any additive which may be trapped around the stopper. Insert tube into holder. Push tube stopper onto needle until leading edge of stopper meets guideline of holder. Tubes will retract slightly. LEAVE IN THIS POSITION. When using 13 mm diameter tubes, it is important to center the tubes in the holder when penetrating the stopper, to preclude sidewall penetration and resultant loss of volume. Select site for venipuncture. Apply tourniquet. Prepare venipuncture site with an appropriate antiseptic. DO NOT PALPATE VENIPUNCTURE SITE AFTER CLEANSING. Place patient's arm in a downward position. Remove needle shield. Perform venipuncture with arm in a downward position and tube stopper uppermost. Push tube onto holder, puncturing diaphragm of stopper. Remove tourniquet as soon as blood appears in tube. Do not allow contents of tube to contact the stopper or the end of the needle during venipuncture procedure. If no blood flows into tube or ceases to flow before an adequate sample is collected, the following steps are suggested to complete satisfactory collection: Confirm correct position of needle cannula in vein; If a multiple sample needle is being used, remove the tube and place a new tube into the holder; If the second tube does not draw, remove needle and discard in appropriate disposal device. Repeat procedure from Step 1. When first tube is full and blood flow ceases, remove it from holder. Place succeeding tubes in holder (following correct order of draw), puncturing diaphragm to initiate flow. Tubes without additives are drawn before tubes with additives. While each successive tube is filling, invert the previous tube containing additives 8-10 times. DO NOT SHAKE. Vigorous mixing can cause hemolysis. As soon as blood stops flowing in the last tube, remove needle from vein, apply pressure to puncture site with dry, sterile swab, until bleeding stops. Apply bandage if desired, except in infants and toddlers. After the venipuncture, the top of the stopper may contain residual blood at the puncture site. Proper precautions should be take when handling tubes to avoid contact with blood droplets. Dispose of any holder that becomes contaminated with blood. Needle disposal: After venipuncture, dispose of needle using appropriate disposal device. DO NOT RECAP NEEDLE. If breakage of a tube containing a collected sample should occur, avoid all contact with the exposed skin and follow proper procedures for the cleanup and disposal of infectious waste.

2 Venipuncture Technique Using A Syringe lab. Syringe Technique Some healthcare workers prefer to use the syringe-needle technique for venipuncture. If this system is used, the blood specimen can be transferred from the syringe directly into the vacuum tube which then will be sent to the reference In order to maintain the integrity of the specimen, drawing and precautionary procedures should proceed as follows:. Inspect tip of needle to determine that it is free from hooks and barbs. The needle should be #21 gauge or larger in order to facilitate rapid flow into and out of the syringe and thus minimize hemolysis. Disposable needles are used routinely.. If one standard size of syringe is used, the 20 ml size is recommended in order to accommodate larger amounts of specimen required for some procedures. Inspect syringe by moving the plunger within the barrel to ensure free movement. NOTE: Disposable plastic syringes are required.. After assembly of the needle/syringe unit, move plunger within unit to ensure syringe and needle patency.. Cleanse venipuncture site with 70% isopropyl alcohol using circular motion towards the periphery. Allow area to dry to prevent burning sensation for patient when venipuncture is performed and to prevent hemolysis of blood.. If vein site must be touched again, cleanse probing finger with alcohol before touching site.. Apply tourniquet around arm 3-4 inches above venipuncture site. Do not leave tourniquet on the arm for more than 1-2 minutes and do not release tourniquet until blood collection is completed.. Grasp patient's arm firmly, placing the thumb 1-2 inches below the chosen site to draw skin taut. This will anchor the vein. If possible, make sure the patient's arm is in a downward position. This will help ensure that no back-flow from the tube will go into the patient's arm.. Perform venipuncture with bevel side of needle up.. Grasp barrel of syringe firmly and pull firmly on plunger until required amount of blood is in the syringe..ask patient to open fist and remove tourniquet as soon as desired amount of blood has been obtained.. Lightly place gauze or cotton pad upon venipuncture site.. Remove needle. Apply direct pressure to pad, have patient keep arm fully extended and elevated.

3 . Apply pressure over site for several minutes. Check site for bleeding. If bleeding has ceased, apply bandage over pad at site and advise patient to leave bandage on for 15 minutes. If site is still bleeding, continue direct pressure on site. Do not bandage until bleeding has ceased.. After the blood specimen has been obtained, the needle should be left on the syringe and inserted through the rubber stopper into the vacuum tube. Do not hold vacuum tube! Stand the tube in a test tube rack while inserting the syringe needle. Allow the vacuum to draw the specimen from the syringe. Do not forcefully eject the blood from the syringe, since the rapid velocity of the blood resulting from this maneuver may damage the blood cells and cause hemolysis or cause the vacuum tube to explode! Blood Collection via Capillary Puncture Technique 1 Fingerstick This technique is useful for adults or children when only small amounts of blood are required. Capillary Puncture may be used in place of venipuncture when small amounts of blood are needed, and: The patient has poor veins for a venipuncture The patient has only one good vein which is to be saved for another procedure The patient is extremely apprehensive about the venipuncture procedure Capillary punctures may be done on earlobes, fingertips, heels, or toes. As the heels and toes of adults tend to be extremely calloused and tough, these spots are used mainly with infants. Earlobes are not a site of choice in that they don't have that many capillaries. There also seems to be some difference in the cell concentrations between capillary blood taken from the earlobe and venous blood. The site of choice is the distal lateral aspect of the fingertip. Usually the second or third finger is used.. Choose the middle or ring finger. If the patient's hands are cold, they may be warmed by holding them under warm running water or by briskly rubbing them. If the patient is able, vigorously washing the hands with warm soapy water will effectively cleanse and soften the skin and increase the blood flow to the fingers. When choosing a finger, try not to use one that has been hanging over the edge of the bed. The blood in these fingers may be congested or concentrated from lack of movement. This can affect test results.. Massage the finger to increase the blood flow. This may be done by milking the finger from hand to tip 5-6 times. Do not overuse this maneuver as it may cause erroneous results due to concentration of tissue fluids.. Cleanse fingertip with 70% isopropyl alcohol. Wipe dry with a clean, dry piece of gauze or cotton. Be sure that the finger is thoroughly dry, as blood will not well up and form a drop at the puncture site of a moist finger.

4 . If you are using a lancet, remove the lancet from its container and grasp the lancet between the thumb and forefinger. If you are using a finger puncture device, you will need to refer to the instructions for the device you are using.. Grasp the patient's finger between the fingers and thumb of your other hand.. With a quick wrist motion, down and up, make a puncture lateral to the ball of the finger. Using this area avoids the nerves found in the ball of the fingertip. The cut should be perpendicular to the lines in the fingerprint so that the blood will form a drop. Punctures made parallel to the fingerprint lines will allow blood to run down the finger.. Using the hands supporting the finger, squeeze it lightly to stimulate the flow of blood. "Milking" the finger from proximal toward the distal end will also be effective in getting a good blood flow. Be careful not to cause erroneous results due to introduction of tissue fluids. The cut should be deep enough so that hard pressure is not required. If gentle pressure is not enough to start blood flow, make another puncture starting at step #4.. Using a piece of dry, clean cotton gauze, wipe off the first drop of blood, as this drop may be contaminated with tissue fluid.. Still holding the finger lightly, fill a capillary pipette or other collecting device. The capillary pipette should be held in an almost horizontal position with the tip touching the drop of blood. The tube should not be allowed to touch the finger. Should more blood be needed, a small test tube or commercial micro tube may be held beneath the finger and blood dropped into it..when sufficient blood has been obtained, place a clean, dry gauze pad or cotton ball over the site and have the patient press with the thumb on the same hand until bleeding has stopped. Blood Collection via Capillary Puncture in Infants Heelstick Usually used in infants under 6 months of age, as fingers are too small. When choosing the site of the heelstick, care should be taken to avoid sites of previous puncture. The punctures should be made on the flat, bottom surface of the foot, not on the posterior curvature of the heel. (The area between the ankle and the bottom of the foot at the back of the heel.) The heel bone (calcaneus) is very close to the skin surface at the back of the heel and could be damaged by a puncture to this area. Cases of infection of the heel bone due to punctures at this site have been reported. The areas of the bottom surface of the newborn's heel contain the best capillary bed and provide protection against damaging the calcaneus. Also, the medial aspect of the foot should NOT be used because of the possibility of damage to nerves found in that area. Capillary procurement should be performed on the lateral aspect of the foot.

5 The National Committee for Clinical Laboratory Standards recently made a change in the standards regarding heel sticks in infants. The depth of an infants heel skin puncture should not exceed 2 mm to avoid hitting a bone. (Changed from 2.4) Beside protecting the calcaneus, this depth is adequate to reach the capillary beds and provide adequate blood flow for specimen collection. A wide variety of lancets are available for capillary puncture. Unfortunately, none are exactly the right length and width to provide a puncture of 2 mm deep and mm in length for a heelstick. Therefore, most experts recommend use of lancets of the correct length which are designed with guards to prevent deep punctures, although the width of the lancet is not ideal. Most experts warn specifically against the use of a surgical blade of any kind for heelstick because of the danger of a deep puncture, infection, and damage to the calcaneus. Preparation of the heelstick site and drawing should proceed as follows:. Warm the heel for 3 minutes prior to puncture with a hot (no more than 42 degree C), moist towel to help increase blood flow to the area. The increase in blood flow has been found to be as much as sevenfold. The blood specimen must be collected immediately after the 3 minute warming, as a moist towel will rapidly cool the heel and slow blood flow as the level cools.. As with fingersticks and venipunctures, it is important to cleanse the puncture site. High risk newborns are especially prone to infection. The antiseptic should remain in contact with the skin for at least 1 minute and should be rubbed off with a dry, sterile swab. If the site is not dried well, the antiseptic can mix with the specimen and the blood will not "bead up" well at the puncture site. Rather, the blood will spread over the moist area, making it difficult to collect.. Thoroughly scrub your hands and arms to the elbow with soap and water.. Place neonate on stomach if possible. Positively identify the patient!. Thoroughly cleanse the plantar surface of the foot with 70% alcohol. NOTE: Vigorous scrubbing of the entire foot bottom helps promote circulation near the skin surface.. Dry the alcohol scrub area with sterile gauze.. Puncture the skin at a degree angle at a site near the lateral margins of the posterior plantar foot. NOTE: The "crown" portion of the heel should not be used. It is too close to the calcaneus.. Wipe away the first drop of blood.. Gently and progressively squeeze the lower leg and ankle using a "tennis racket" grip.

6 . Place a sterile gauze over the puncture site after collection until the puncture wound seals. Occasionally, a small bandage is required, but should not be used unless absolutely necessary because of the sensitive nature of neonatal skin.. Watch for any signs of distress from the patient that are unusual or appear to impair cardiopulmonary function. Be careful not to displace any lines or monitoring devices attached to the patient!