Principles Of Medical Laboratory Science Practice 2 (Clinical Laboratory Assistance And Phlebotomy) (LAB) PDF

Principles of Medical Laboratory Science Practice 2 (Clinical Laboratory Assistance and Phlebotomy) (LAB) Module 7: Arterial Puncture Procedures 2nd Semester l Finals l University of San Agustin l Outline be required to perform arterial  P...

Principles of Medical Laboratory Science Practice 2 (Clinical Laboratory Assistance and Phlebotomy) (LAB) Module 7: Arterial Puncture Procedures 2nd Semester l Finals l University of San Agustin l Outline be required to perform arterial  Performance & Personnel puncture include:  Purpose o Nurses  Sites & Criteria o medical technologists and  Pre Analytical Procedures technicians  Modified Allen Test o respiratory therapists  Radial Artery Collection & Role of o emergency medical technicians Phlebotomist in other sites o Level II phlebotomists.  Hazards, Sample Errors and Specimen Rejection  Phlebotomists who collect arterial specimens must have extensive ARTERIAL PUNCTURE training involving theory, demonstration of technique,  Technically difficult observation of the actual procedure,  Potentially more painful and performance of arterial puncture  Hazardous than venipuncture. with supervision before performing arterial punctures on their own.  Consequently, arterial specimens are not normally used for routine blood  Personnel who perform ABG testing are tests, even though arterial blood designated level I or level II depending composition is more consistent on their formal education, training, and throughout the body than venous, which experience. varies relative to the metabolic needs o Level II personnel supervise of the area it serves. level 1 personnel and perform testing as well.  The primary reason for arterial puncture is to obtain blood for arterial blood  For quality assurance purposes, gas (ABG) tests, which evaluate individuals performing arterial puncture respiratory function. must undergo periodic evaluation.  Those who do not meet acceptable  Arterial blood is the best specimen for standards must have remedial evaluating respiratory function instruction and be re-evaluated before because of its normally high oxygen being allowed to collect arterial content and consistency of specimens independently. composition.  Capillary blood, which is similar to SITE SELECTION arterial blood in composition provided that the puncture site is warmed prior  The artery used for collection must be to specimen collection, is sometimes located near the skin surface and be used to test blood gases in infants. large enough to accept at least a 23- gauge needle. Personnel Who Perform Arterial Puncture  In addition, the region distal to the collection site should have collateral  Paramedical personnel (healthcare circulation, meaning that it receives workers other than physicians) who may blood from more than one artery. TRANSCRIBED BY: ALYSSANDRA FRANCINE S. DORAN I USA MLS 1-F I Page 1 2 PMLS 2: Clinical Laboratory Assistance and Phlebotomy (Lab)  This allows the tissue to remain fully The radial artery oxygenated during the collection procedure.  Artery of choice  Although it is smaller than either the  Collateral circulation is tested using the brachial or the femoral artery, it has modified Allen test. good collateral circulation and is easily accessible along the thumb side  Artery accessibility and size of the wrist. o The more accessible and larger an artery is, the easier it is to  The ulnar artery provides collateral palpate and puncture. circulation to the hand.  Type of tissue surrounding the  The radial artery can be compressed puncture site between the ligaments and the bones, o The chosen artery should be in allowing easy application of pressure an area that poses little risk of after puncture and reducing the chance injuring adjacent structures or of hematoma. tissue during puncture, helps fix or secure the artery to keep it  Its small size is a disadvantage in from rolling, and allows adequate patients with low cardiac output pressure to be applied to the because it is hard to locate. artery after specimen collection. The brachial artery  Absence of inflammation, irritation,  Large edema, hematoma, lesion or a wound,  It is easy to palpate and puncture. an arterioventricular (AV) shunt in close  It is located in the antecubital fossa, proximity, or a recent arterial puncture at below the basilic vein and near the the site. insertion of the biceps muscle. ARTERIES USED FOR ARTERIAL  It has adequate collateral circulation, PUNCTURE although not as much as the radial  Phlebotomists collect only from the artery. radial or brachial arteries; other collections require a physician or other  Nevertheless, the brachial artery has specially trained professional. important disadvantages.  Other arteries that can be used include o It is deep and is close to the the femoral and dorsalis pedis. median nerve. o Puncturing the median nerve is a significant risk in brachial artery collection. o Also, unlike the radial artery, the brachial artery lies in soft tissue and therefore is more difficult to compress, increasing the risk of hematoma and bleeding into the puncture site. TRANSCRIBED BY: ALYSSANDRA FRANCINE S. DORAN I USA MLS 1-F I Page 2 3 PMLS 2: Clinical Laboratory Assistance and Phlebotomy (Lab) The femoral artery o 1-inch needle is used for either the brachial or the radial artery  Largest artery used. o 1 1⁄2 inch needle is used for the  It is located in the groin area above the femoral artery. thigh, lateral to the pubic bone. Antiseptic  The femoral is used when the  Alcohol and povidone–iodine or previously mentioned sites are not chlorhexidine are used to clean the site. available for puncture.  Its large size and high volume make it Lidocaine Anesthetic useful when cardiac output is low.  However, it has poor collateral  To lessen pain, 0.5 mL of lidocaine may circulation. be injected subcutaneously, using a 25- to 26-gauge needle on a 1-mL syringe.  In addition, it is a difficult site to keep Safety Equipment aseptic, increasing the risk of infection, and the puncture itself may dislodge  Fluid-resistant gown, face protection, accumulated plaque from the arterial and gloves and puncture resistant walls. container for sharps.  Only personnel with advanced training Luer Tip can perform femoral artery puncture.  This plastic tip covers the syringe top Alternative sites in adults include the dorsalis after you have removed the needle. pedis artery in the foot.  This keeps air from reaching the specimen and altering gas  When puncturing the dorsalis pedis, the concentrations. posterior tibial must be checked for an adequate pulse. Other Equipment In infants, the umbilical artery and scalp artery  Crushed ice are used.  Ice and water  Gauze pads In newborns who have difficulty breathing,  Pressure bandages blood may be collected from both the  Thermometer (to take the patient’s umbilical artery and the umbilical vein. These temperature) samples are tested separately and the results  Transport container No tourniquet is compared needed because arterial blood is under EQUIPMENTS FOR ARTERIAL PUNCTURE pressure. Heparinized Syringe and Needle  Arterial blood is collected in a syringe that has been pre-treated with heparin to prevent coagulation.  Syringes must be either glass or gas- impermeable plastic.  Syringe volumes range from 1 to 5 mL.  The typical collection needle is usually 21 or 22 gauge, and 1 to 11⁄2 inches long. TRANSCRIBED BY: ALYSSANDRA FRANCINE S. DORAN I USA MLS 1-F I Page 3 4 PMLS 2: Clinical Laboratory Assistance and Phlebotomy (Lab) PRE ANALYTICAL PROCEDURES MODIFIED ALLEN TEST Identification & explanation of procedures Testing Collateral Circulation  Proper identification of the patient,  The modified Allen test is the most explain the procedure and obtain common method used to assess the patient’s consent. adequacy of collateral circulation in  The patient must be treated in a the radial artery. pleasant, professional and reassuring  It is performed without the use of manner to minimize apprehension or special equipment. anxiety which can lead to  If the test result is positive, arterial hyperventilation, breath holding or crying puncture can be performed on the which may erroneously affect results. radial artery.  If the result is negative, arterial puncture Patient preparation & assessment should not be performed on that arm  Patient should be relaxed and in a and the patient’s nurse or physician comfortable position. should be notified of the problem.  Anticoagulant therapy should also be RADIAL ARTERIAL BLOOD GAS noted, allergies of the patient. PROCEDURE Steady state  Puncture of the radial artery can be  Patient should be in a steady state for performed only if it is determined that there is collateral circulation provided at least 20 to 30 minutes because temperature, breathing pattern and by the ulnar artery and the site meets other selection criteria previously oxygen concentration being inhaled can affect the ABG results. described. PREPARING AND ADMINISTERING LOCAL 1. Position the Arm ANESTHETIC  Position the patient’s arm out to the side, 1. Verify absence of allergy to anesthetic or away from the body (abducted) with the its derivatives palm facing up and the wrist supported. 2. Sanitize hands & don gloves (A rolled towel placed under the wrist is 3. Attach needle to syringe typically used to provide support.) 4. Clean stopper of anesthetic bottle w.  Ask the patient to extend the wrist at alcohol wipe approximately a 30-degree angle to 5. Insert needle through bottle stopper & stretch and fi x the tissue over the withdraw anesthetic ligaments and bone of the wrist. 6. Carefully replace needle cap & put 2. Locate the Artery syringe in horizontal position 7. Clean & air-dry site  Use the index finger of your 8. Insert needle into skin at site at angle of nondominant hand to locate the radial 10 degrees artery pulse proximal to the skin crease 9. Pull back slightly on plunger on the thumb side of the wrist. 10. Slowly expel contents into skin, forming  Palpate the artery to determine its size, a raised wheal direction, and depth. 11. Wait 1 to 2 min. before proceeding w. arterial puncture CAUTION: Never use the thumb to palpate, 12. Note anesthetic application on requisition as it has a pulse that can be misleading. TRANSCRIBED BY: ALYSSANDRA FRANCINE S. DORAN I USA MLS 1-F I Page 4 5 PMLS 2: Clinical Laboratory Assistance and Phlebotomy (Lab) 3. Clean the Site When the flash appears, stop advancing the needle. Do not pull back on the  Prepare the site by cleaning with syringe plunger. alcohol or another suitable antiseptic.  The blood will pump, or pulse, into the  Allow the site to air dry, being careful not syringe under its own power unless a to touch it with any unsterile object. needle smaller than 23-gauge is used, in which case a gentle pull on the plunger 4. Prepare Equipment may be required. Hold the syringe very  Attach the safety needle to the syringe if steady until the desired amount of blood not pre-assembled and set the syringe is collected. plunger to the proper fill level if  If the artery is missed, slowly withdraw applicable. the needle until the bevel is just under  Put on gloves if they were not put on in the skin before redirecting the needle step 6 and clean the gloved non- into the artery. dominant finger so that it does not 7. Withdraw the Needle and Apply Pressure contaminate the site when relocating the pulse before needle entry.  When the desired amount of blood has been obtained, withdraw the needle, 5. Insert the Needle immediately place a folded clean and  Pick up and hold the syringe or collection dry gauze square over the site with device in your dominant hand as if you one hand, and simultaneously activate were holding a dart. Uncap and inspect the needle safety device with the other the needle for defects. (Discard and hand or place the needle in an approved replace it if flawed.) needle removal safety device.  Relocate the artery by placing the index  Apply firm pressure to the puncture site finger of the opposite hand directly over for a minimum of 3 to 5 minutes. the pulse. Warn the patient of imminent  Longer application of pressure is puncture and ask him or her to relax the required for patients on anticoagulant wrist as much as possible while therapy. maintaining its extended position. CAUTION: Never allow the patient to apply  Direct the needle away from the hand, the pressure. A patient may not apply it firmly facing into the arterial blood flow, and enough. insert it bevel-up into the skin at a 30- to 45-degree angle (femoral puncture  In addition, do not replace use of requires a 90-degree angle) manual pressure for the required length approximately 5 to 10 millimeters distal of time with the application of a pressure to the index finger that is locating the bandage. pulse. 8. Remove Air, Cap Syringe, and Mix CAUTION: Do not probe. Probing is painful Specimen and can cause hematoma or thrombus formation or damage the artery  While applying pressure to the site with one hand, use your free hand to remove 6. Advance the Needle into the Artery the safety needle and discard it in a sharps container. Handle the specimen  Slowly advance the needle, directing it carefully to avoid introducing air bubbles toward the pulse beneath the index into it, as they can affect test results. If finger. any air bubbles are present, immediately  When the artery is pierced, a “flash” of eject them from the specimen. If the blood will appear in the needle hub. equipment has an air bubble removal TRANSCRIBED BY: ALYSSANDRA FRANCINE S. DORAN I USA MLS 1-F I Page 5 6 PMLS 2: Clinical Laboratory Assistance and Phlebotomy (Lab) cap, follow manufacturer’s instructions. omit the last step (transportation and Cap the syringe and gently but handling). thoroughly mix the specimen by inversion or rotation to prevent clot ABG COLLECTION FROM OTHER SITES formation. Label the specimen.  Collection of ABGs from brachial, 9. Check the site femoral, and other sites is similar to the procedure for radial ABGs.  After applying pressure for 3 to 5  Because phlebotomists are not normally minutes, check the site. trained to collect specimens from these  The skin below the site should be sites, specific procedures are not given normal in color and warm to the in this text. touch, with no evidence of bleeding or  Phlebotomists may, however, be asked swelling. to provide the equipment and assist in  If bleeding, swelling, or bruising is noted, labeling and transporting specimens reapply pressure for an additional 2 collected from these sites by others. minutes. Repeat this process if necessary until you are certain that COMPLICATIONS, SAMPLE ERRORS AND bleeding has stopped. If the site appears REJECTION normal, wait 2 minutes and check it ARTERIAL PUNCTURE COMPLICATIONS again. Then check the pulse distal to the site.  Arteriospasm, the spontaneous  If the pulse is absent or faint or the constriction of an artery in response to patient complains of numbness at the pain. site, alert the patient’s nurse or physician o Arteriospasm may close the immediately, because a thrombus may artery, preventing oxygen from be blocking blood flow. If the site reaching tissue. appears normal and the pulse is normal, apply a pressure bandage and make a  Embolism, or blood vessel notation as to when the bandage may be obstruction, due to an air bubble or removed. dislodged clot in the artery. o This can cause arterial occlusion CAUTION: Never leave the patient if the site (blockage), leading to loss of is still bleeding. If bleeding does not stop within blood flow. a reasonable time, notify the patient’s nurse or physician.  Hematoma, resulting from inadequate 10. Wrap-up Procedures pressure on the site. o This is more likely in elderly  Make certain the specimen has been patients, whose artery walls are properly labelled before leaving the not as elastic and thus not as patient’s bedside. likely to close spontaneously.  Dispose of used equipment properly. Remove gloves and face protection and  Hemorrhage. This is more likely in wash or decontaminate hands with patients who have coagulation sanitizer. disorders or are receiving anticoagulant  Thank the patient. therapy (heparin or warfarin).  If ABG testing has already been performed by POCT instrumentation,  Infection, from skin contaminants. verify that the results have been Contaminants are easily carried to the recorded and transmitted to the lab and TRANSCRIBED BY: ALYSSANDRA FRANCINE S. DORAN I USA MLS 1-F I Page 6 7 PMLS 2: Clinical Laboratory Assistance and Phlebotomy (Lab) rest of the body without encountering the prevented by using a Luer tip to cover immune system. the syringe after you remove the needle.  Mixing insufficiently, causing the  Lightheadedness, nausea, or fainting. specimen to clot.  Puncturing a vein instead of an artery.  Nerve damage, caused by inadvertent  Using an improper anticoagulant, as pH contact with a nerve. This is more likely is altered by ethylenediaminetetraacetic during arterial puncture than acid (EDTA), oxalates, and citrates. venipuncture because the needle passes  Using an improper plastic syringe, which more deeply into tissue. allows atmospheric gas to diffuse in and specimen gases to diffuse out through  Severe pain. the plastic.  Using too little heparin, causing the  Thrombosis, or clot formation, within the specimen to clot. artery  Using too much heparin, which lowers the pH value. SAMPLING ERRORS SPECIMEN REJECTION  Arterial collections are particularly prone to technical errors that affect the values  Air bubbles in the specimen determined in the laboratory.  Clotting  The most significant source of error is  Failure to ice the specimen failure to deliver the sample to the  Improper or absent labeling laboratory immediately or to properly  Inadequate volume of specimen for the store the sample on ice if delivery will be test delayed.  Too long a delay in delivering the  Blood cells continue to respire after specimen to the laboratory collection, and this may cause  Use of the wrong syringe considerable changes in the analyte values, including Po2, Pco2, and pH. 1. Samples collected in a plastic syringe are not iced, and must be analyzed within 30 minutes of collection. 2. Samples collected in a glass syringe may be iced if they are not to be delivered to the laboratory within 5 to 10 minutes. 3. Iced samples must be delivered within 1 hour. 4. Ice should not be used if the sample is being tested for potassium because lower temperatures affect those levels. Other sources of error include:  Allowing air bubbles to enter the syringe, decreasing the carbon dioxide reading.  Exposing the specimen to the atmosphere after collection, which is TRANSCRIBED BY: ALYSSANDRA FRANCINE S. DORAN I USA MLS 1-F I Page 7 Principles of Medical Laboratory Science Practice 2 (Clinical Laboratory Assistance and Phlebotomy) (LAB) Module 7: Arterial Puncture Procedures 2nd Semester l Finals l University of San Agustin l TRANSCRIBED BY: ALYSSANDRA FRANCINE S. DORAN I USA MLS 1-F I Page 8 9 PMLS 2: Clinical Laboratory Assistance and Phlebotomy (Lab) TRANSCRIBED BY: ALYSSANDRA FRANCINE S. DORAN I USA MLS 1-F I Page 9